Molecular Predictors Of Outcome Research Articles

752P Clinical and molecular predictors of outcome in patients with tubo-ovarian high-grade serous carcinoma and exceptional survival

752P Clinical and molecular predictors of outcome in patients with tubo-ovarian high-grade serous carcinoma and exceptional survival

Whole exome sequencing identifies clinically relevant mutational signatures in resected hepatocellular carcinoma

AbstractBackground & AimsMost patients develop recurrent disease despite curative surgery for hepatocellular carcinoma (HCC). No standard adjuvant therapy is available and molecular predictors of outcome are poorly understood.MethodsWe conducted a multicentre pilot study on patients with localized HCC following surgical resection. Patients received up to 6 months of oral gefitinib as adjuvant therapy. Clinical end points included recurrence‐free survival (RFS) and overall survival (OS), and exploratory analyses were conducted from whole exome sequencing data.ResultsA total of 65 patients were screened for the study, of which 40 were eligible. The median age was 63 years (range, 44‐80). Most patients (80%) were positive for hepatitis B or C. With a median follow‐up of 4.5 years, the median RFS was 24 months. Median OS was not reached. High Child‐Pugh score and advanced T‐stage (3‐4) were independent predictors for both OS and RFS. Mutational signatures for exposure to aristolochic acid (AA), as characterized by a majority of T:A > A:T mutations, were observed in 18 cases (55%). HCC without AA mutagenesis was associated with early recurrences or death within 2 years of surgery (P = .037). HCC with high T > A mutations was associated with better OS (HR 0.29, 95% CI 0.09‐0.90, P = .033). Conversely, HCC with high C > T mutations was associated with worse OS (HR 4.55, 95% CI 1.20‐17.31, P = .026).ConclusionsMutational signatures may carry prognostic significance in HCC following curative resection. Patient outcomes with gefitinib as adjuvant therapy after resection for HCC were modest, highlighting the need for urgent research in this area of unmet clinical need. ClinicalTrials.gov number, NCT00282100.

Bridging the treatment gap in infant medulloblastoma: molecularly informed outcomes of a globally feasible regimen.

Infant medulloblastoma represents an enormous challenge in neuro-oncology, due to their simultaneous high-risk of recurrence and high risk of severe neurodevelopmental sequelae with craniospinal irradiation. Currently infant medulloblastoma are treated with intensified protocols, either comprising intraventricular methotrexate or autologous transplant, both of which carry significant morbidity and are not feasible in the majority of the world. We sought to evaluate the molecular predictors of outcome in a cohort of infants homogeneously treated with induction chemotherapy, focal radiation and maintenance chemotherapy. In a retrospective analysis, 29 young children treated with a craniospinal irradiation sparing strategy from Hospital Garrahan in Buenos Aires were profiled using Illumina HumanMethylationEPIC arrays, and correlated with survival. Twenty-nine children (range, 0.3-4.6 y) were identified, comprising 17 sonic hedgehog (SHH), 10 Group 3/4, and 2 non-medulloblastomas. Progression-free survival (PFS) across the entire cohort was 0.704 (95% CI: 0.551-0.899). Analysis by t-distributed stochastic neighbor embedding revealed 3 predominant groups, SHHβ, SHHγ, and Group 3. Survival by subtype was highly prognostic with SHHγ having an excellent 5-year PFS of 100% (95% CI: 0.633-1) and SHHβ having a PFS of 0.56 (95% CI: 0.42-1). Group 3 had a PFS of 0.50 (95% CI: 0.25-1). Assessment of neurocognitive outcome was performed in 11 patients; the majority of survivors fell within the low average to mild intellectual disability, with a median IQ of 73.5. We report a globally feasible and effective strategy avoiding craniospinal radiation in the treatment of infant medulloblastoma, including a robust molecular correlation along with neurocognitive outcomes.

Precision Health for Chagas Disease: Integrating Parasite and Host Factors to Predict Outcome of Infection and Response to Therapy.

Chagas disease, caused by the infection with the protozoan parasite Trypanosoma cruzi, is clinically manifested in approximately one-third of infected people by inflammatory heart disease (cardiomyopathy) and, to a minor degree, gastrointestinal tract disorders (megaesophagus or megacolon). Chagas disease is a zoonosis transmitted among animals and people through the contact with triatomine bugs, which are found in much of the western hemisphere, including most countries of North, Central and South America, between parallels 45° north (Minneapolis, USA) and south (Chubut Province, Argentina). Despite much research on drug discovery for T. cruzi, there remain only two related agents in widespread use. Likewise, treatment is not always indicated due to the serious side effects of these drugs. On the other hand, the epidemiology and pathogenesis of Chagas disease are both highly complex, and much is known about both. However, it is still impossible to predict what will happen in an individual person infected with T. cruzi, because of the highly variability of parasite virulence and human susceptibility to infection, with no definitive molecular predictors of outcome from either side of the host-parasite equation. In this Minireview we briefly discuss the current state of T. cruzi infection and prognosis and look forward to the day when it will be possible to employ precision health to predict disease outcome and determine whether and when treatment of infection may be necessary.

NRG Oncology/NSABP B-51/RTOG 1304: Phase III trial to determine if chest wall and regional nodal radiotherapy (CWRNRT) post mastectomy (Mx) or the addition of RNRT to whole breast RT post breast-conserving surgery (BCS) reduces invasive breast cancer recurrence-free interval (IBCR-FI) in patients (pts) with pathologically positive axillary (PPAx) nodes who are ypN0 after neoadjuvant chemotherapy (NC).

TPS600 Background: This phase III post-NC trial evaluates if CWRNRT post-Mx or whole breast irradiation (WBI) with RNRT after BCS significantly reduces the IBCR-FI rate in pts with PPAx nodes that are pathologically negative after NC. Secondary aims are OS, LRR-FI, DR-FI, DFS-DCIS, second primary cancer, and comparison of RT effect on cosmesis in reconstructed Mx pts. Correlative science examines RT effect by tumor subtype, molecular outcome predictors for residual disease, and predictors for the degree of reduction in loco-regional recurrence. Methods: Clinical T1-3, N1 IBC PPAx nodes (FNA or core needle biopsy) pts complete ≥8 weeks of NC (anthracycline and/or taxane). HER2+ pts receive anti-HER2 therapy. Following NC, BCS or Mx, sentinel node biopsy (≥2 nodes) and/or Ax dissection with histologically negative nodes is performed. ER/PR and HER-2neu status before NC is required. Pts may receive appropriate adjuvant systemic therapy. Radiation credentialing with a facility questionnaire/case benchmark is required. Random assignment for Mx pts is to no CWRNRT or CWRNRT and for BCS pts to WBI or WBI+RNRT. Statistics: 1,636 pts are to be enrolled over 5 yrs (definitive analysis at 7.5 yrs). Study is powered at 80% to test that RT reduces the annual hazard rate of events for IBCR-FI by 35% for an absolute risk reduction of 4.6% (5-yr cumulative rate). Intent-to-treat analysis with 3 interim analyses (43, 86, and 129 events) and a 4th/final analysis at 172 events. Pt-reported outcomes focusing on RT effect will be provided by 736 pts before random assignment and at 3, 6, 12, and 24 mos. Accrual as of 2-7-19 is 1,164 (71.1%). Contacts: Protocol: CTSU member website https://www.ctsu.org . Questions: NRG Oncology Pgh Clin Coord Dpt: 1-800-477-7227 or ccd@nsabp.org . Pt entry: OPEN at https://open.ctsu.org or the OPEN tab on CTSU member website. Support: U10 CA-2166; -180868, -180822; 189867; Elekta NCT01872975 Clinical trial information: NCT01872975.

Abstract OT2-04-01: Phase III trial to determine if chest wall and regional nodal radiotherapy (CWRNRT) post mastectomy (Mx) or the addition of RNRT to whole breast RT post breast-conserving surgery (BCS) reduces invasive breast cancer recurrence-free interval (IBCR-FI) in patients (pts) with pathologically positive axillary (PPAx) nodes who are ypN0 after neoadjuvant chemotherapy (NC): NRG Oncology/NSABP B-51/RTOG 1304

Abstract This phase III post-NC trial evaluates if CWRNRT post-Mx or whole breast irradiation (WBI) with RNRT after BCS significantly reduces the IBCR-FI rate in pts with PPAx nodes that are pathologically negative after NC. Secondary aims are OS, LRR-FI, DR-FI, DFS-DCIS, second primary cancer, and comparison of RT effect on cosmesis in reconstructed Mx pts. Correlative science examines RT effect by tumor subtype, molecular outcome predictors for residual disease, and predictors for the degree of reduction in loco-regional recurrence. Methods: Clinical T1-3, N1 IBC PPAx nodes (FNA or core needle biopsy) pts complete ≥8 weeks of NC (anthracycline and/or taxane). HER2+ pts receive anti-HER2 therapy. Following NC, BCS or Mx, sentinel node biopsy (≥2 nodes) and/or Ax dissection with histologically negative nodes is performed. ER/PR and HER-2neu status before NC is required. Pts may receive appropriate adjuvant systemic therapy. Radiation credentialing with a facility questionnaire/case benchmark is required. Random assignment for Mx pts is to no CWRNRT or CWRNRT and for BCS pts to WBI or WBI+RNRT. Statistics: 1,636 pts are to be enrolled over 5 yrs (definitive analysis at 7.5 yrs). Study is powered at 80% to test that RT reduces the annual hazard rate of events for IBCR-FI by 35% for an absolute risk reduction of 4.6% (5-yr cumulative rate). Intent-to-treat analysis with 3 interim analyses (43, 86, and 129 events) and a 4th/final analysis at 172 events. Pt-reported outcomes focusing on RT effect will be provided by 736 pts before random assignment and at 3, 6, 12, and 24 mos. Accrual as of 6-21-18 is 967 (59.11%). Contacts: Protocol: CTSU member website https://www.ctsu.org. Questions: NRG Oncology Pgh Clin Coord Dpt: 1-800-477-7227 or ccd@nsabp.org. Pt entry: OPEN at https://open.ctsu.org or the OPEN tab on CTSU member website. NCT01872975 Support: U10 CA-2166; -180868, -180822; 189867; Elekta Citation Format: Mamounas EP, Bandos H, White JR, Julian TB, Khan AJ, Shaitelman SF, Torres MA, Vicini FA, Ganz PA, McCloskey SA, Paik S, Gupta N, Li XA, DiCostanzo DJ, Curran WJ, Wolmark N. Phase III trial to determine if chest wall and regional nodal radiotherapy (CWRNRT) post mastectomy (Mx) or the addition of RNRT to whole breast RT post breast-conserving surgery (BCS) reduces invasive breast cancer recurrence-free interval (IBCR-FI) in patients (pts) with pathologically positive axillary (PPAx) nodes who are ypN0 after neoadjuvant chemotherapy (NC): NRG Oncology/NSABP B-51/RTOG 1304 [abstract]. In: Proceedings of the 2018 San Antonio Breast Cancer Symposium; 2018 Dec 4-8; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2019;79(4 Suppl):Abstract nr OT2-04-01.

Pathology and Pathogenesis of Chagas Heart Disease

Chagas heart disease is an inflammatory cardiomyopathy that develops in approximately one-third of people infected with the protozoan parasite Trypanosoma cruzi. One way T. cruzi is transmitted to people is through contact with infected kissing bugs, which are found in much of the Western Hemisphere, including in vast areas of the United States. The epidemiology of T. cruzi and Chagas heart disease and the varied mechanisms leading to myocyte destruction, mononuclear cell infiltration, fibrosis, and edema in the heart have been extensively studied by hundreds of scientists for more than 100 years. Despite this wealth of knowledge, it is still impossible to predict what will happen in an individual infected with T. cruzi because of the tremendous variability in clonal parasite virulence and human susceptibility to infection and the lack of definitive molecular predictors of outcome from either side of the host-parasite equation. Further, while several distinct mechanisms of pathogenesis have been studied in isolation, it is certain that multiple coincident mechanisms combine to determine the ultimate outcome. For these reasons, Chagas disease is best considered a collection of related but distinct illnesses. This review highlights the pathology and pathogenesis of the most common adverse sequela of T. cruzi infection-Chagas heart disease-and concludes with a discussion of key unanswered questions and a view to the future.

MA25.11 Clinical and Molecular Predictors of Outcome in Patients with EGFR mutant NSCLC Brain Metastases treated with RT

MA25.11 Clinical and Molecular Predictors of Outcome in Patients with EGFR mutant NSCLC Brain Metastases treated with RT

Prognostic Factors and Survival of Gliomatosis Cerebri: A Systematic Review and Meta-Analysis

Gliomatosis cerebri (GC) is a fatal diffusely infiltrating glioma. Because of its rarity, only scarce evidence is available regarding outcome predictors and the proper management of GC. Reported studies of patients with histologically confirmed GC were systematically reviewed and individual patient-level data (n= 523) extracted. Multivariable Cox proportional hazard models were fit for overall survival (OS) and progression-free survival (PFS). The median OS and PFS were 13 and 10 months, with 5-year rates of 18% and 13%, respectively. Age ≥65 years at diagnosis (hazard ratio for OS [HROS], 2.32; 95% confidence interval [CI], 1.62-3.31), high-grade tumor (HRPFS for grade III, 1.57; 95% CI, 1.02-2.40; HRPFS for grade IV, 1.74; 95% CI, [0.98-3.10), GC type II (HROS, 1.49; 95% CI, 1.12-1.98; HRPFS, 1.56; 95% CI, 1.04-2.34), more central nervous system (CNS) regions involved (HROS, 1.09; 95% CI, 1.01-1.18), focal neurological deficits (HROS, 1.41; 95% CI, 1.07-1.86), cerebellar symptoms (HRPFS, 2.20; 95% CI, 1.42-3.39), more symptoms at presentation (HROS, 1.21; 95% CI, 1.05-1.40), Karnofsky performance scale score <70 (HROS, 3.58; 95% CI, 1.73-7.39; HRPFS, 4.48; 95% CI, 1.39-14.4), magnetic resonance imaging contrast enhancement (HROS, 1.48; 95% CI, 1.12-1.96; HRPFS, 1.74; 95% CI, 1.18-2.55), symmetric bilateral CNS invasion (HROS, 1.42; 95% CI, 1.03-1.96), and high proliferation index (Ki-67 >5%; HROS, 2.32; 95% CI, 1.11-4.86) were independent predictors of poor outcomes. In contrast, seizure occurrence (HROS, 0.77; 95% CI, 0.60-1.00; HRPFS, 0.68; 95% CI, 0.47-0.95), isocitrate dehydrogenase 1 mutation (HROS, 0.16; 95% CI, 0.05-0.49), and O6-methylguanine-DNA-methyltransferase promoter methylation (HROS, 0.23; 95% CI, 0.09-0.59) were associated with prolonged survival. Chemotherapy and surgical resection were associated with improved outcomes, but radiotherapy, whether monotherapy or combined with chemotherapy, was not superior to chemotherapy alone. In the largest study to date on GC, we have identified clinical, imaging, and molecular outcome predictors that are similar to other gliomas and highlight the beneficial effect of chemotherapy and surgical resection, when feasible, on outcomes.

Abstract OT2-03-02: NRG oncology/NSABP B-51/RTOG 1304: Phase III trial to determine if chest wall and regional nodal radiotherapy (CWRNRT) post mastectomy (Mx) or the addition of RNRT to breast RT post breast-conserving surgery (BCS) reduces invasive breast cancer recurrence-free interval (IBCR-FI) in patients (pts) with positive axillary (PAx) nodes who are ypN0 after neoadjuvant chemotherapy (NC)

Abstract Background: This phase III post-NC trial evaluates if CWRNRT post-Mx or whole breast irradiation (WBI) with RNRT after BCS significantly reduces the IBCR-FI rate in pts with PAx nodes that are negative after NC. Secondary aims are OS, LRR-FI, DR-FI, DFS-DCIS, second primary cancer, and comparison of RT effect on cosmesis in reconstructed Mx pts. Correlative science examines RT effect by tumor subtype, molecular outcome predictors for residual disease pts, and predictors for the degree of reduction in locoregional recurrence. Methods: Clinical T1-3, N1 IBC PAx nodes (FNA or core needle biopsy) pts complete ≥8 weeks of NC (anthracycline and/or taxane). HER2+ pts receive anti-HER2 therapy. Following NC, BCS or Mx, sentinel node biopsy (≥2 nodes) and/or Ax dissection with histologically negative nodes is performed. ER/PR and HER-2neu status before NC is required. Pts receive required systemic therapy. Radiation credentialing with a facility questionnaire/case benchmark is required. Random assignment for Mx pts is to no CWRNRT or CWRNRT and for BCS pts to WBI or WBI+RNRT. Statistics: 1636 pts to be enrolled over 5 yrs (definitive analysis at 7.5 yrs). Study is powered at 80% to test that RT reduces the annual hazard rate of events for IBCR-FI by 35% for an absolute risk reduction of 4.6% (5-yr cumulative rate). Intent-to-treat analysis with 3 interim analyses (43, 86, and 129 events) and a 4th/final analysis at 172 events. Pt-reported outcomes focusing on RT effect will be provided by 736 pts before random assignment and at 3, 6, 12, and 24 mos. Accrual as of 6-12-17 is 645 (39.43%). Contacts: Protocol: CTSU member website https://www.ctsu.org. Questions: NRG Oncology Pgh Clin Coord Dpt: 1-800-477-7227 or ccd@nsabp.org. Pt entry: OPEN at https://open.ctsu.org or the OPEN tab on CTSU member website. Support: U10 CA-2166; -180868, -180822; 189867; Elekta. Citation Format: Mamounas EP, Bandos H, White JR, Julian TB, Khan AJ, Shaitelman SF, Torres MA, Vicini FA, Ganz PA, McCloskey SA, Paik S, Gupta N, Li XA, DiCostanzo DJ, Curran Jr WJ, Wolmark N. NRG oncology/NSABP B-51/RTOG 1304: Phase III trial to determine if chest wall and regional nodal radiotherapy (CWRNRT) post mastectomy (Mx) or the addition of RNRT to breast RT post breast-conserving surgery (BCS) reduces invasive breast cancer recurrence-free interval (IBCR-FI) in patients (pts) with positive axillary (PAx) nodes who are ypN0 after neoadjuvant chemotherapy (NC) [abstract]. In: Proceedings of the 2017 San Antonio Breast Cancer Symposium; 2017 Dec 5-9; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2018;78(4 Suppl):Abstract nr OT2-03-02.

NRG Oncology/NSABP B-51/RTOG 1304: Phase III trial to determine if chest wall and regional nodal radiotherapy (CWRNRT) post mastectomy (Mx) or the addition of RNRT to breast RT post breast-conserving surgery (BCS) reduces invasive breast cancer recurrence free interval (IBCRFI) in patients (pts) with positive axillary (PAx) nodes who are ypN0 after neoadjuvant chemotherapy (NC).

TPS589 Background: This phase III post-NC trial evaluates if CWRNRT post-Mx or whole breast irradiation (WBI) with RNRT after BCS significantly reduces the IBCR-FI rate in pts with PAx nodes that are negative after NC. Secondary aims are OS, LRR-FI, DR-FI, DFS-DCIS, second primary cancer, and comparison of RT effect on cosmesis in reconstructed Mx pts. Correlative science examines RT effect by tumor subtype, molecular outcome predictors for residual disease pts, and predictors for the degree of reduction in locoregional recurrence. Methods: Clinical T1-3, N1 IBC PAx nodes (FNA or core needle biopsy) pts complete ≥12 weeks of NC (anthracycline and/or taxane). HER2+ pts receive anti-HER2 therapy. Following NC BCS or Mx, sentinel node biopsy (≥3 nodes) and/or Ax dissection with histologically negative nodes is performed. ER/PR and HER-2neu status before NC is required. Pts receive required systemic therapy. Radiation credentialing with a facility questionnaire/case benchmark is required. Random assignment for Mx pts is to no CWRNRT or CWRNRT and for BCS pts to WBI or WBI RNRT. Statistics: 1636 pts to be enrolled over 5 yrs (definitive analysis at 7.5 yrs). Study is powered at 80% to test that RT reduces the annual hazard rate of events for IBCR-FI by 35% for an absolute risk reduction of 4.6% (5-yr cumulative rate). Intent-to-treat analysis with 3 interim analyses (43, 86, and 129 events) and a 4th/final analysis at 172 events. Pt-reported outcomes focusing on RT effect will be provided by 736 pts before random assignment and at 3, 6, 12, and 24 mos. Accrual as of 2-2-17 is 534 (32.64%). Contacts: Questions: NRG Oncology Pgh Clin Coord Dpt: 1-800-477-7227 or ccd@nsabp.org . Support: U10 CA-2166; -180868, -180822; 189867; Elekta Clinical trial information: NCT01872975.

Abstract OT2-03-01: NRG oncology/NSABP B-51/RTOG 1304: A phase III superiority clinical trial designed to determine if chest wall and regional nodal radiotherapy (CWRNRT) post mastectomy (Mx) or the addition of RNRT to breast RT post breast-conserving surgery (BCS) will reduce invasive cancer events in patients (pts) with positive axillary (Ax) nodes and convert to ypN0 after neoadjuvant chemotherapy (NC)

Abstract Background: This phase III post-NC trial evaluates if CWRNRT post Mx or whole breast irradiation (WBI) with RNRT after BCS significantly reduces the invasive breast cancer recurrence-free interval (IBC-RFI) rate in pts presenting with positive Ax nodes that are pathologically negative after NC. Secondary aims are OS, LRRFI, DRFI, DFS-DCIS, and second primary cancer, as well as comparing RT effect on cosmesis in reconstructed Mx pts. Correlative science studies examine RT effect by tumor subtype, molecular outcome predictors for residual disease pts, and predictors for the degree of reduction in loco-regional recurrence. Methods: Clinical T1-3, N1 IBC pts with positive Ax nodes (FNA or core needle biopsy) complete ≥8 wks of NC (anthracycline and/or taxane). HER2-positive pts receive anti-HER2 therapy (tx). After NC, BCS or Mx is performed with a sentinel node biopsy (≥2 nodes) and/or Ax dissection with histologically negative nodes. ER/PR and HER2 neu status before NC is required. Pts receive required systemic tx. Radiation credentialing with a facility questionnaire and a case benchmark is required. Randomization for Mx pts is to no CWRNRT or CWRNRT and for BCS pts to WBI or WBI+RNRT. Statistics: 1636 pts to be enrolled over 5 yrs with definitive analysis at 7.5 yrs. Study is powered at 80% to test that RT reduces the annual hazard rate of events for IBCR-FI by 35% for an absolute risk reduction in the 5-yr cumulative rate of 4.6%. Intent-to-treat analysis with 3 interim analyses at 43, 86, and 129 events, with a 4th/final analysis at 172 events will occur. Accrual as of 6/13/16 is 356. Pt-reported outcomes focusing on RT effect will be obtained from 736 pts before randomization and at 3, 6, 12, and 24 months. Contacts: Protocol: CTSU member website https://www.ctsu.org. Questions: NRG Oncology Pgh Clin Coord Dpt: 1-800-477-7227 or ccd@nsabp.org. Pt entry: OPEN at https://open.ctsu.org or the OPEN tab on CTSU member website. Support: U10 CA-2166; -180868, -180822; -189867; Elekta. Citation Format: Mamounas EP, Bandos H, White JR, Julian TB, Khan AJ, Shaitelman SF, Torres MA, Vicini FA, Ganz PA, McCloskey SA, Paik S, Gupta N, Li XA, DiCostanzo DJ, Curran, Jr WJ, Wolmark N. NRG oncology/NSABP B-51/RTOG 1304: A phase III superiority clinical trial designed to determine if chest wall and regional nodal radiotherapy (CWRNRT) post mastectomy (Mx) or the addition of RNRT to breast RT post breast-conserving surgery (BCS) will reduce invasive cancer events in patients (pts) with positive axillary (Ax) nodes and convert to ypN0 after neoadjuvant chemotherapy (NC) [abstract]. In: Proceedings of the 2016 San Antonio Breast Cancer Symposium; 2016 Dec 6-10; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2017;77(4 Suppl):Abstract nr OT2-03-01.

Molecular Predictors of Outcome and Drug Response in Multiple Myeloma: An Interim Analysis of the Mmrf CoMMpass Study

The Multiple Myeloma Research Foundation (MMRF) CoMMpass trial (NCT145429) is a longitudinal study of 1147 patients with newly-diagnosed multiple myeloma from clinical sites in the United States, Canada, Spain, and Italy. Each patient receives a treatment regimen containing a proteasome inhibitor, immunomodulatory agent, or both. Clinical parameters are collected at study enrollment and every three months through the eight-year observation period. To identify molecular determinants of clinical outcome each baseline and progression tumor specimen is characterized using Whole Genome Sequencing, Exome Sequencing, and RNA sequencing. Data available as of January 1, 2016 is included in this first formal interim analysis, which includes 995 enrolled patients of whom 851 are molecularly characterized. This cohort of patients includes 74 patients with at least two sequential samples, plus 15 patients with characterized tumor samples from the bone marrow and peripheral blood.The median follow-up of the cohort is 66 weeks, which identified a median PFS of 36 months for the cohort. The median OS was not reached but 76% are still alive at 3 years. Although the age at enrollment by gender is uniform, there is a significant difference in PFS and OS, with males performing worse than females, p=0.001 and p=0.0004 respectively. Analysis of the exome sequencing data from the 746 baseline BM localized tumors identified a median of 122 non-immunoglobulin related mutations per patient, with an interquartile range of 96-155. There is a group of highly mutated (>481 mutations [mean+1SD]) patients who frequently have MAF family translocations (66%) and/or mutations in the DNA repair genes MSH2, MSH3, MSH4, MSH6, or ATM (38%). Across the cohort 21/53 of the DNA repair gene mutations reside in these 21 patients compared to 14/47 MAF family translocations. Analysis of the somatic mutations identified 20 significant genes, which are recurrently mutated and the mutated allele is detectably expressed; BRAF, CYLD, DIS3, FAM46C, FCF1, FGFR3, FUBP1, KRAS, MAX, NFKBIA, NRAS, PRKD2, RASA2, RB1, SAMHD1, SP140, TGDS, TP53, TRAF2, and TRAF3. Integration of the copy number data and the mutation data identified an association between TP53 deletion and mutation, suggesting many patients present with homozygous loss of TP53. Patients with one or two functional TP53 alleles had similar PFS and OS but the patients with zero functional alleles had a significantly reduced OS (p<0.05). Therefore, the existing association between 17p deletion and outcome is driven by the subpopulation of patients with bi-allelic TP53 loss. Analysis of the whole genome sequencing data available from the 719 baseline BM localized tumors for immunoglobulin translocations identified the expected canonical translocations along with events targeting MYC in 14.6% of patients. Unlike the canonical translocations the MYC translocations are enriched in hyperdiploid tumors (22.3%) and often involve light chain loci, particularly the lambda locus. Within the hyperdiploid patients, those with a MYC translocation have a reduced PFS. To identify molecular subtypes we performed unsupervised clustering using a consensus clustering approach on the 613 baseline BM tumors with RNA sequencing data, which identified 12 distinct subtypes. This analysis confirmed previous studies identifing distinct subtypes associated with WHSC1, MAF/MAFA/MAFB translocations and two subtypes associated with CCND1/CCND2/CCND3 subtypes, which can be separated by CD20 expression. Five subtypes are associated with hyperdiploid myeloma, one group is nearly devoid of chromosome 11 gains while this event is ubiquitous in the remaining hyperdiploid groups. The genomic profiles of the paired tumors isolated from the peripheral blood and bone marrow share 87% of the observed events with unique events being more common in the PB compartment suggesting the PB compartments are often derived from a closely related progenitor clone of the bulk BM tumor. Applying our bayesian clonal analysis method to the serial samples identified multiple clones in all patients with some showing no changes in clonal populations while the majority show significant shifts in clonal burden. These analyses have identified tumor initiating mutations and new subtypes of myeloma, which are associated with distinct molecular events and clinical outcomes. DisclosuresNiesvizky:Celgene: Consultancy, Research Funding, Speakers Bureau; Takeda: Consultancy, Research Funding, Speakers Bureau; Onyx: Consultancy, Research Funding, Speakers Bureau. Wolf:Takeda: Honoraria; Telomere Diagnostics: Consultancy; Amgen: Honoraria; Celgene: Honoraria; Pharmacyclics: Honoraria. Lonial:Onyx: Consultancy; BMS: Consultancy; Novartis: Consultancy; Janssen: Consultancy; Janssen: Consultancy; Merck: Consultancy; Onyx: Consultancy; Celgene: Consultancy; Millenium: Consultancy; Novartis: Consultancy; BMS: Consultancy; Celgene: Consultancy.

Phase III Randomized Study of R-CHOP Versus DA-EPOCH-R and Molecular Analysis of Untreated Diffuse Large B-Cell Lymphoma: CALGB/Alliance 50303

▪Background: Diffuse large B-cell lymphoma (DLBCL) is comprised of multiple diseases with different outcomes, cell of origin and molecular pathogenesis. DLBCL derived from germinal center B-cells (GCB) and activated B-cells (ABC) constitutes over 80% of DLBCL. A small number of DLBCL tumors harbor MYC translocations, which are associated with a poorer prognosis. Primary mediastinal B-cell lymphoma (PMBL) occurs in younger patients and is typically treated with intensive or combined modality therapy. R-CHOP is the standard of care for DLBCL but has not been prospectively studied within DLBCL molecular subtypes. DA-EPOCH-R is an alternative and more dose-intensive regimen that showed a PFS of 81% at 4-years in a phase II multicenter CALGB study (Haematologica 2012; 97:758). CALGB/Alliance undertook a phase III randomized study to compare R-CHOP and DA-EPOCH-R in DLBCL and specifically within the GCB and ABC subtypes.Methods: Patients had stage II or higher newly diagnosed DLBCL, age ≥ 18 years and were HIV negative. Subjects were randomized 1:1 to receive R-CHOP or DA-EPOCH-R as previously published. Central nervous system prophylaxis in at-risk patients was 12 mg intrathecal methotrexate in cycles 3-6 (4 doses total). All subjects with accessible tumor were required to have a biopsy or waiver. Subjects received a total of 6 treatment cycles. The primary study endpoints were EFS of R-CHOP (Arm A) versus DA-EPOCH-R (Arm B) and to develop a molecular predictor of outcome based on GCB and ABC DLBCL. Additional analyses include toxicity, pharmacogenomics and analysis of tumor genetics by next generation sequencing, and.Results: 524 patients registered (262 on each arm) between May 2005 and May 2013. Efficacy analysis includes R-CHOP (n=233) and R-EPOCH (n=231) assigned patients with confirmed eligibility who received any treatment. Characteristics of patients registered to Arm A and B did not differ with median age (58; 56), male sex (53.2%; 53.7%), high-intermediate/high IPI (33.6%; 38.2%) and primary mediastinal B-cell lymphoma histology (6.9%; 5.2%). Therapy was completed per protocol in 89% and 83%, respectively, for Arm A and B, and disease progression on therapy was 2.6% and 1.7%. Adverse side effects leading to treatment discontinuation were 1.7% and 5.6%, respectively, for Arm A and B. Arm B compared to Arm A was associated with more grade 4 neutropenia (90%; 56%), grade 4 thrombocytopenia (35%; 6%), grade 3/4 febrile neutropenia (37%; 19%) and grade 3 neuropathy (motor: 8%;1% and sensory: 15%; 3%). Grade 5 events on study were the same in both arms. Preliminary analysis of EFS in confirmed eligible subjects shows no difference between Arm A and B with hazard ratio of 1.02 and p=0.89 at a median follow-up of 4.9 years. Overall survival is also similar with hazard ratio of 1.19 and p=0.40 at median 5.0 years. Additional analyses of EFS and OS by age (<60 and >=60) and by GCB versus ABC DLBCL are in process. Conclusions: There was no difference in EFS or OS between R-CHOP and DA-EPOCH-R when considering all patients. DA-EPOCH-R showed increased toxicity consistent with higher dose-intensity but not increased grade 5 toxicity. Compared to R-CHOP, more patients on DA-EPOCH-R did not complete treatment, which may reflect patterns of care or toxicity. Due to the clinical and genetic diversity of DLBCL, subset analyses are necessary to determine the effect of CNS relapse, GCB and ABC subtypes, age and IPI on outcomes of the two arms. These data do not address the efficacy of these regimens in PMBL or MYC+ DLBCL due to their low frequency, and where more dose-intense regimens appear to be important. Full molecular analyses are ongoing. Support: U10CA180821, U10CA180882, U10CA180888, CA180799, CA180820, CA180833, CA21076, CA21115.ClinicalTrials.gov Identifier: NCT00118209. DisclosuresHsi:Cellerant Therapeutics: Honoraria, Research Funding; Eli Lilly: Research Funding; Abbvie: Honoraria, Research Funding; Seattle Genetics: Honoraria, Speakers Bureau; HTG Molecular Diagnostics: Consultancy, Honoraria. Friedberg:Bayer: Honoraria, Other: Data Safety Monitoring Board. Cheson:Pharmacyclics: Membership on an entity's Board of Directors or advisory committees, Research Funding; Acerta: Membership on an entity's Board of Directors or advisory committees, Research Funding; Gilead: Research Funding. Bartlett:Gilead: Consultancy. Kahl:This study was coordinated by the ECOG-ACRIN Cancer Research Group (Robert L. Comis, MD and Mitchell D. Schnall, MD, PhD, Group Co-Chairs) and supported by the National Cancer Institute of the National Institutes of Health under the following award number: Research Funding. Zelenetz:Gilead Sciences: Research Funding.

Impact of allogeneic hematopoietic cell transplant in patients with myeloid neoplasms carrying spliceosomal mutations.

Molecular predictors of outcome are increasingly important in determining optimal therapy for myeloid neoplasms. Mutations in the spliceosomal genes (U2AF1 and SRSF2) predict for poor outcomes in myelodysplastic syndromes (MDS) and related diseases. We investigated the effect of hematopoietic cell transplant (HCT) on the negative prognostic impact of U2AF1 and SRSF2 mutations. In total, 122 patients with MDS (30%), acute myeloid leukemia (51%), myeloproliferative neoplasms (MPN) (11%), and MDS/MPN (8%) receiving a HCT from 2003 to 2012 were evaluated for mutations in U2AF1 and SRSF2 by direct sequencing. Median time of follow up was 24 months (range 0.46-110). SRSF2 mutations were detected in 11 (10%) patients and U2AF1 in 3 (3%) patients. There were no significant differences in baseline characteristics between mutated and wild-type (WT) patients. Patients carrying SRSF2 and U2AF1 mutations had similar overall survival (P = 0.84), relapse mortality (P = 0.50), and non-relapse mortality (P = 0.72) compared to WT patients. However, taking into account disease status and cytogenetics in a subset of AML patients, SRSF2 and U2AF1 mutations were associated with worse survival (HR 3.71, P = 0.035).

Abstract S3-02: Molecular predictors of outcome on adjuvant CAF plus tamoxifen (T) vs T in postmenopausal patients (pts) with ER+, node+ breast cancer – Transcriptome expression analysis of the phase III trial SWOG-8814

Abstract BACKGROUND: In SWOG-8814A, pts with ER+ node+ breast cancer and low 21 gene recurrence scores (RS) had good prognosis and no CAF benefit, but high RS predicted longer survival from CAF followed by T (CAF-T) vs T (Albain, Lancet Oncol 2010). The aims of SWOG-8814B were to identify novel genes and networks for 1) prognosis of early and late relapse and 2) prediction of CAF benefit, using whole transcriptome expression analysis with next generation RNA sequencing (NGS). METHODS: Stored RNA previously extracted for SWOG-8814A (T, CAF-T arms; T, 5 yrs) was analyzed for RNA/library yield (see companion abstract Cherbavaz et al. for methods). Genes were sequenced and expression of mRNA species was related to disease-free survival (DFS) using Cox proportional hazards. Discovery analyses controlled false discovery rate (FDR) at 10%. Genes were identified for prognosis on T and prediction on CAF-T vs T. Networks of genes/pathways were explored. Early (0-5 yrs) and late (5-13+ yrs) time periods were studied. Gene Ontology, Cytoscape, pathway and hierarchical clustering were used for functional gene and metagene analyses. RESULTS: Of 367 samples, 354 (96%; 142 T, 212 CAF-T; 141 DFS events) had sufficient RNA/library yield, with 20,101 genes sequenced. For prognosis on T, there were 2327 and 568 genes discovered in early and all-yrs follow-up, with only 9 genes prognostic after 5 yrs. Prognosis analyses for residual risk after CAF-T were uninformative. Functional mapping found that genes prognostic for worse DFS were enriched for proliferation (G2M, M-phase), cellular metabolism, DNA repair, stress response and EMT; whereas, those with better DFS involved transcription regulation/repression via zinc finger proteins. Hierarchical clustering (T arm) found significant DFS prognostic metagene signatures for ER-related genes, immune response, ECM/stroma, chromatin remodeling-transcription factor activity and TGFb pathway. All varied for early vs late DFS events. For example, low ER/high stroma expression signatures correlated with high proliferation gene expression and were strongly associated with early events (standardized [st] HR 2.94, p&amp;lt;0.001). Late recurrence was associated with high proliferation, both individually (stHR 1.51, p=.035) and in combination with higher ER expression (stHR 1.51, p=0.09). Fifteen genes predicted CAF benefit (9 better DFS, 6 worse), or 129 genes if FDR relaxed to 20%. Cluster analysis for CAF prediction is ongoing. CONCLUSIONS: Unique genes, clusters and pathways were identified by NGS of archival material in ER+ N+ breast cancer, including previously unreported signatures. While ER, stroma and proliferation-related signatures were associated with early prognosis, proliferation best predicted worse DFS after 5 yrs. NGS of the primary tumor is most informative for early events in pts with only 5 years of T, with few genes selecting only for late relapse. If validated, these signatures may identify pts with excellent DFS despite positive nodes for endocrine therapy alone as well as others for whom chemotherapy and/or biologics are also required . SUPPORT: NCI CA 180888, 180819, 180821, 180820, 180863; in part, Genomic Health, Inc. Citation Format: Albain KS, Crager MR, Barlow WE, Baehner FL, Bergamaschi A, Rae JM, Ravdin PM, Tripathy D, Gralow JR, Livingston RB, Osborne CK, Ingle JN, Pritchard KI, Davidson NE, Carey LA, Cherbavaz DB, Sing AP, Shak S, Hortobagyi GN, Hayes DF. Molecular predictors of outcome on adjuvant CAF plus tamoxifen (T) vs T in postmenopausal patients (pts) with ER+, node+ breast cancer – Transcriptome expression analysis of the phase III trial SWOG-8814. [abstract]. In: Proceedings of the Thirty-Eighth Annual CTRC-AACR San Antonio Breast Cancer Symposium: 2015 Dec 8-12; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2016;76(4 Suppl):Abstract nr S3-02.

Abstract OT2-02-02: NRG Oncology/NSABP B-51/RTOG 1304: A phase III clinical trial to determine if chest wall and regional nodal radiotherapy (CWRNRT) post mastectomy (Mx) or the addition of RNRT to breast RT post breast-conserving surgery (BCS) will reduce invasive cancer events in patients (pts) with positive axillary (Ax) nodes who are ypN0 after neoadjuvant chemotherapy (NC)

Abstract Background: This phase III post-NC trial will evaluate if CWRNRT post Mx or whole breast irradiation (WBI) with RNRT after BCS significantly reduces the invasive breast cancer recurrence-free interval (IBC-RFI) rate in pts presenting with positive Ax nodes that are negative after NC. Secondary aims are OS, LRRFI, DRFI, DFS-DCIS, and second primary cancer as well as comparing RT effect on cosmesis in reconstructed Mx pts. Correlative science examines RT effect by tumor subtype, molecular outcome predictors for residual disease pts, and predictors for the degree of reduction in loco-regional recurrence. Methods: Clinical T1-3, N1 IBC pts with positive Ax nodes (FNA or core needle biopsy) complete ≥12 wks of NC (anthracycline and/or taxane). HER2-positive pts receive anti-HER2 therapy (tx). After NC BCS or Mx is performed with a sentinel node biopsy (≥3 nodes) and/or Ax dissection with histologically negative nodes. ER/PR and HER-2 neu status before NC is required. Pts receive required systemic tx. Radiation credentialing with a facility questionnaire and a case benchmark is required. Randomization for Mx pts is to no CWRNRT or CWRNRT and for BCS pts to WBI or WBI RNRT. Statistics: 1,636 pts to be enrolled over 5 yrs with definitive analysis at 7.5 yrs. Study is powered at 80% to test that RT reduces the annual hazard rate of events for IBCR-FI by 35% for an absolute risk reduction in the 5-yr cumulative rate of 4.6%. Intent-to-treat analysis with 3 interim analyses at 43, 86, and 129 events, with a 4th/final analysis at 172 events will occur. Accrual as of 6/4/15 is 143. Pt-reported outcomes focusing on RT effect will be provided by 736 pts before randomization and at 3, 6, 12, and 24 months. Contacts: Protocol: CTSU member website https://www.ctsu.org. Questions: NRG Oncology Pgh Clin Coord Dpt: 1-800-477-7227 or ccd@nsabp.org. Pt entry: OPEN at https://open.ctsu.org or the OPEN tab on CTSU member website. Support: U10 CA-2166; -180868, -180822; -189867; Elekta. Citation Format: Mamounas EP, Bandos H, White JR, Julian TB, Khan AJ, Shaitelman SF, Torres MA, Vicini FA, Ganz PA, McCloskey SA, Paik S, Gupta N, Li XA, DiCostanzo DJ, Costantino JP, Curran Jr WJ, Wolmark N. NRG Oncology/NSABP B-51/RTOG 1304: A phase III clinical trial to determine if chest wall and regional nodal radiotherapy (CWRNRT) post mastectomy (Mx) or the addition of RNRT to breast RT post breast-conserving surgery (BCS) will reduce invasive cancer events in patients (pts) with positive axillary (Ax) nodes who are ypN0 after neoadjuvant chemotherapy (NC). [abstract]. In: Proceedings of the Thirty-Eighth Annual CTRC-AACR San Antonio Breast Cancer Symposium: 2015 Dec 8-12; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2016;76(4 Suppl):Abstract nr OT2-02-02.

Phyllodes tumours of the breast: a consensus review.

Phyllodes tumours constitute an uncommon but complex group of mammary fibroepithelial lesions. Accurate and reproducible grading of these tumours has long been challenging, owing to the need to assess multiple stratified histological parameters, which may be weighted differently by individual pathologists. Distinction of benign phyllodes tumours from cellular fibroadenomas is fraught with difficulty, due to overlapping microscopic features. Similarly, separation of the malignant phyllodes tumour from spindle cell metaplastic carcinoma and primary breast sarcoma can be problematic. Phyllodes tumours are treated by surgical excision. However, there is no consensus on the definition of an appropriate surgical margin to ensure completeness of excision and reduction of recurrence risk. Interpretive subjectivity, overlapping histological diagnostic criteria, suboptimal correlation between histological classification and clinical behaviour and the lack of robust molecular predictors of outcome make further investigation of the pathogenesis of these fascinating tumours a matter of active research. This review consolidates the current understanding of their pathobiology and clinical behaviour, and includes proposals for a rational approach to the classification and management of phyllodes tumours.

Molecular Predictors of Outcome in Patients with MDS and AML Following MDS after Allogeneic Hematopoietic Stem Cell Transplantation

Introduction: The landscape of molecular aberrations in patients with myelodysplastic syndromes (MDS) has been well characterized and has identified ASXL1, BCOR, CUX1, IDH1, IDH2, SRSF2, RUNX1, U2AF1, TP53 and others as negative prognostic markers for overall survival (OS). We comprehensively investigated the prognostic impact of genetic aberrations in the context of allogeneic hematopoietic stem cell transplantation (alloHSCT) in a large cohort of patients with high risk MDS or secondary AML following MDS (sAML). Patients and Methods: 308 Patients with a diagnosis of MDS (47.4%) or sAML (52.6%) who received an alloHSCT at four German university medical centers and for whom genomic DNA was available at a time with active disease before transplantation were evaluated for the presence of mutations in 54 genes by Illumina high-throughput sequencing. Results: At least one mutation was identified in 82% of our patients with a median number of 2 mutations per patient. The most frequently mutated genes were ASXL1 (24.4%), DNMT3A, (23.1%), RUNX1 (16.9%), TET2 (16.9%), STAG2 (12%), TP53 (11.7%), and SRSF2 (11%) in agreement with previous reports. Mutation frequencies were similar between MDS and sAML patients for all mutated genes except SRSF2, TET2 and WT1, which were more frequently mutated in sAML. We grouped the mutated genes into functional classes and found that patients most frequently had mutations in modifiers of DNA methylation (42.2%), followed by chromatin modifiers (41.5%), splicing genes (31.1%), transcription factors (30.8%), signal transducers (28.8%) and tumor suppressors (14.6%). Mean variant allele frequencies were highest in modifiers of DNA methylation (33.2%), while signal transducers had the lowest allele frequency (20.4%). We next assessed the prognostic impact of gene classes and individual genes on outcome of patients after alloHSCT. Median follow up from transplantation was 4.15 years. Median patient age at time of HSCT was 58 years (range 19-75). 76 patients (25%) werein complete remission and 232 patients (75%) had active disease before transplantation. Low, intermediate, and high risk cytogenetics according to IPSS were found in 116 (38%), 59 (19%), and 115 (37%) patients, respectively. Matched and mismatched related donor HSCT was performed in 71 and 4 patients, respectively (23.1 and 1.3%), and matched and mismatched unrelated donor HSCT in 171 and 62 patients, respectively (55.5 and 20.1%). The six functional gene classes had no prognostic impact on survival, cumulative incidence of relapse and non-relapse mortality. We therefore evaluated the prognostic impact of individual gene mutations, of aberrations of chromosomes 3, 5, 7, 8, 17, 20 or a complex karyotype, and of transplant characteristics on OS. Parameters with significant impact on OS in univariate analysis were included in a multivariate cox proportional hazards model. Significant predictors of OS in multivariate analysis were mutations in PTPN11 (HR 3.1, present in 2.3% of pts.), IDH2 (HR 2.6, present in 4.2%), PHF6 (HR 2.2, present in 4.9%), NRAS (HR 1.8, present in 7.5%), presence of a complex karyotype (HR 1.8, present in 16.6%), transplantation from haploidentical donor (HR 5.5), RAEB/sAML not in complete remission before transplantation compared to untreated RA/RARS or RAEB/sAML and treated RAEB/sAML in remission (HR 2.0), GvHD prophylaxis other than calcineurin inhibitor with methotrexate or mycophenolate mofetil (HR 1.7) and female sex of the donor (HR 1.7). TP53 mutations lost their unfavorable prognostic impact when complex karyotype was added to the multivariate model. Competing risk analysis for cumulative incidence of relapse and non-relapse mortality showed that IDH2 and NRAS mutations and a complex karyotype were significantly associated with higher risk for relapse while PTPN11 and PHF6 mutations predicted for a higher incidence of non-relapse mortality. Importantly, a negative prognostic impact of ASXL1, BCOR, CUX1, IDH1, SRSF2, RUNX1 and U2AF1 seen previously in MDS patients not undergoing alloHSCT was not found in the transplant setting, suggesting that alloHSCT may overcome the unfavorable effect of these mutations. Conclusion: By extensive genetic characterisation of 308 MDS or sAML patients undergoing alloHSCT we identified mutations in IDH2, NRAS and complex karyotype as predictors of relapse and reduced OS and provide a matrix to refine risk prediction for allogeneic HSCT. Disclosures Heuser: Karyopharm: Research Funding. Platzbecker:Boehringer: Research Funding; Celgene: Honoraria, Research Funding; Novartis: Honoraria, Research Funding. Thiede:Novartis: Honoraria, Membership on an entity's Board of Directors or advisory committees, Research Funding; AgenDix GmBH: Equity Ownership.

Abstract OT1-3-02: Will chest wall and regional nodal radiotherapy post mastectomy or the addition of regional nodal radiotherapy to breast radiotherapy post lumpectomy reduce the rate of invasive cancer events in patients with positive axillary nodes who convert to ypN0 af

Abstract Background This phase III randomized post-neoadjuvant chemotherapy trial will evaluate if chest wall and regional nodal XRT (CWRNRT) after mastectomy or whole breast irradiation (WBI) with RNRT after breast-conserving surgery significantly reduces the rate of events for invasive breast cancer recurrence-free interval (IBCR-FI) in patients who present with histologically positive axillary nodes but become histologically negative axillary nodes after neoadjuvant chemotherapy. Secondary aims are OS, LRR-FI, DRFI, DFS-DCIS, and second primary cancer. HYPOTHESIS: Can We Use Tumor and Nodal Response to Neoadjuvant Chemotherapy in Order to Individualize the Use of L-R XRT? Correlative science will examine the effect of RT by tumor subtype, molecular predictors of outcome for patients with residual disease, and the development of predictors of degree of reduction in loco-regional recurrence. Methods Eligible patients with clinical T1-3, N1 breast cancer with pathologic axillary nodal involvement (positive FNA or core needle biopsy) must complete ≥12 weeks of neoadjuvant chemotherapy (anthracycline and/or taxane-based regimen). HER2-positive patients must receive neoadjuvant trastuzumab or other anti-HER2 therapy. After neoadjuvant chemotherapy either breast-conserving surgery or mastectomy will be performed. At the time of surgery, all removed axillary nodes must be histologically free from cancer. 3 or more histologically negative sentinel nodes are acceptable to determine axillary nodal involvement. ER/PR and HER-2 neu status before neoadjuvant chemotherapy is required. All patients will receive additional required systemic therapy. Site radiation credentialing with a facility questionnaire and case benchmarking is required. Randomization for mastectomy patients will be to no CWRNRT or CWRNRT and for breast-conserving surgery patients to WBI or WBI RNRT. Statistical Considerations 1636 patients will be enrolled over 5 years with definitive analysis at 7.5 years. The study is powered at 80% to test the main hypothesis that RT reduces the annual hazard rate of events for IBCR-FI by 35% for an absolute risk reduction in the 5-year cumulative rate of 4.6%. Analysis will be on intent-to-treat with 3 formal interim analyses at 43, 86, and 129 events, with a 4th/final analysis at 172 events. Current accrual is 37. (as of 6-10-14) 736 enrolled patients will be evaluated with targeted patient-reported outcome instruments focusing on the effect of RT. Patient assessments will be prior to randomization and then at 3, 6, 12, and 24 months. Contact Information Study protocol information can be found under the protocol-specific web page on the CTSU member web site https://www.ctsu.org. For protocol-specific questions contact – NRG Oncology Pittsburgh Clinical Coordinating Department. Phone: 1-800-477-7227. Email: ccd@nsabp.org. All investigators will enroll patients by accessing OPEN at https://open.ctsu.org or from the OPEN tab on the CTSU members’ side of the web site. Support: NCI PHS U10-CA-12027, -69651, -37377, -69974, and -2166. Citation Format: Eleftherios P Mamounas, Hanna Bandos, Julia R White, Thomas B Julian, Atif J Khan, Simona F Shaitelman, Mylin A Torres, Susan A McCloskey, Frank A Vicini, Patricia A Ganz, Soonmyung Paik, Nilendu Gupta, Joseph P Costantino, Walter J Curran Jr, Norman Wolmark. Will chest wall and regional nodal radiotherapy post mastectomy or the addition of regional nodal radiotherapy to breast radiotherapy post lumpectomy reduce the rate of invasive cancer events in patients with positive axillary nodes who convert to ypN0 af [abstract]. In: Proceedings of the Thirty-Seventh Annual CTRC-AACR San Antonio Breast Cancer Symposium: 2014 Dec 9-13; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2015;75(9 Suppl):Abstract nr OT1-3-02.