NCCN Clinical Practice Guidelines Research Articles

Rectal Cancer, Version 2.2022, NCCN Clinical Practice Guidelines in Oncology.

This selection from the NCCN Guidelines for Rectal Cancer focuses on management of malignant polyps and resectable nonmetastatic rectal cancer because important updates have been made to these guidelines. These recent updates include redrawing the algorithms for stage II and III disease to reflect new data supporting the increasingly prominent role of total neoadjuvant therapy, expanded recommendations for short-course radiation therapy techniques, and new recommendations for a "watch-and-wait" nonoperative management technique for patients with cancer that shows a complete response to neoadjuvant therapy. The complete version of the NCCN Guidelines for Rectal Cancer, available online at NCCN.org, covers additional topics including risk assessment, pathology and staging, management of metastatic disease, posttreatment surveillance, treatment of recurrent disease, and survivorship.

Myeloproliferative Neoplasms, Version 3.2022, NCCN Clinical Practice Guidelines in Oncology.

The classic Philadelphia chromosome-negative myeloproliferative neoplasms (MPN) consist of myelofibrosis, polycythemia vera, and essential thrombocythemia and are a heterogeneous group of clonal blood disorders characterized by an overproduction of blood cells. The NCCN Clinical Practice Guidelines in Oncology (NCCN Guidelines) for MPN were developed as a result of meetings convened by a multidisciplinary panel with expertise in MPN, with the goal of providing recommendations for the management of MPN in adults. The Guidelines include recommendations for the diagnostic workup, risk stratification, treatment, and supportive care strategies for the management of myelofibrosis, polycythemia vera, and essential thrombocythemia. Assessment of symptoms at baseline and monitoring of symptom status during the course of treatment is recommended for all patients. This article focuses on the recommendations as outlined in the NCCN Guidelines for the diagnosis of MPN and the risk stratification, management, and supportive care relevant to MF.

Timely Genetic Testing and Therapy Management in Patients With gBRCA-Mutated Metastatic Breast Cancer Receiving Talazoparib.

Talazoparib is a poly(ADP-ribose) polymerase (PARP) inhibitor that has demonstrated strong efficacy with manageable side effects for patients with germline breast cancer susceptibility genes 1 or 2 (gBRCA1/2)- mutated, human epidermal growth factor receptor 2–negative, locally advanced or metastatic breast cancer (mBC) in the EMBRACA and ABRAZO trials. The NCCN Clinical Practice Guidelines in Oncology (NCCN Guidelines®) for Breast Cancer recommend genetic testing for all patients with recurrent or metastatic BC to identify those with a gBRCA1/2 mutation who would benefit from treatment with a PARP inhibitor. However, many patients who meet these criteria do not receive genetic testing for a variety of reasons. Advanced practitioners (APs) can play a key role in the care of these patients by guiding them through the genetic testing process and explaining how the results impact treatment choices. A hypothetical case study highlighting a 42-year-old woman who received a diagnosis of triple-negative mBC provides an example of genetic testing strategies, as well as management considerations, with the use of talazoparib that can be implemented by APs. The efficacy and safety of talazoparib are reviewed along with practical guidance on its use (i.e., managing adverse events and drug interactions) to optimize patient outcomes. The patient case described in this publication is fictional and does not represent actual events or a response from an actual patient. The authors developed this fictional case for educational purposes only.

Soft Tissue Sarcoma, Version 2.2022, NCCN Clinical Practice Guidelines in Oncology.

Soft tissue sarcomas (STS) are rare malignancies of mesenchymal cell origin that display a heterogenous mix of clinical and pathologic characteristics. STS can develop from fat, muscle, nerves, blood vessels, and other connective tissues. The evaluation and treatment of patients with STS requires a multidisciplinary team with demonstrated expertise in the management of these tumors. The complete NCCN Clinical Practice Guidelines in Oncology (NCCN Guidelines) for Soft Tissue Sarcoma provide recommendations for the diagnosis, evaluation, and treatment of extremity/superficial trunk/head and neck STS, as well as retroperitoneal/intra-abdominal STS, desmoid tumors, and rhabdomyosarcoma. This portion of the NCCN Guidelines discusses general principles for the diagnosis and treatment of retroperitoneal/intra-abdominal STS, outlines treatment recommendations, and reviews the evidence to support the guidelines recommendations.

Breast Cancer, Version 3.2022, NCCN Clinical Practice Guidelines in Oncology.

The therapeutic options for patients with noninvasive or invasive breast cancer are complex and varied. These NCCN Clinical Practice Guidelines for Breast Cancer include recommendations for clinical management of patients with carcinoma in situ, invasive breast cancer, Paget disease, phyllodes tumor, inflammatory breast cancer, and management of breast cancer during pregnancy. The content featured in this issue focuses on the recommendations for overall management of ductal carcinoma in situ and the workup and locoregional management of early stage invasive breast cancer. For the full version of the NCCN Guidelines for Breast Cancer, visit NCCN.org.

Increased adherence to molecular profiling recommendations in non–small cell lung cancer through use of prior authorization and peer review.

9129 Background: National oncology guidelines advocate for broad molecular profiling to detect potentially actionable driver mutations prior to initiation of first-line therapy for patients with advanced non-small cell lung cancer (NSCLC). Results of genomic tests can confirm the presence of specific cancer tumor mutations that are best treated with more targeted therapies. Recent studies have shown that up to 30% of lung cancer patients may not receive the most effective treatment due to a lack of guideline-concordant genomic testing. We analyzed data from our prior authorization medical oncology program to determine adherence to national guidelines recommendations, and then developed a program to improve adherence to broad molecular profiling utilizing our proprietary prior authorization algorithms and our proactive peer consultation model. Methods: eviCore healthcare uses the NCCN Clinical Practice Guidelines in Oncology (NCCN Guidelines) to support its proprietary program for medical oncology drug management, and requires attestation on the results of NCCN recommended genomic/molecular test results in advanced NSCLC during prior authorization of systemic therapy. In November 2019, we implemented a next-generation sequencing (NGS) testing results requirement for metastatic non-squamous NSCLC patients prior to first-line therapy approval. If testing had not been completed, a peer to peer consultation was performed to advocate for testing prior to initiation of chemoimmunotherapy regimens. The rate of appropriate tumor testing is defined by provider attestation of test results prior to initiation of therapy. We define the control period (pre- implementation) as October 2018 through September 2019 ( n = 667). The measurement period (post-implementation) is January 2020 through December 2020 ( n = 390). Results: From pre to post there was a 35% increase in testing adherence (p < 0.001). After the testing requirement was implemented, the appropriate tumor testing rate increased to 99% by the second half of 2020, compared to the control period (62%). Additionally, after the testing requirement began, pembrolizumab utilization for advanced stage NSCLC decreased by a net 4.2% per month. This decrease in pembrolizumab utilization likely reflected patients being matched to more appropriate targeted therapy based on genomic testing results. Conclusions: We demonstrate that by combining medical oncology prior authorization with focused peer consultation, adherence to national society recommendations for broad molecular profiling prior to initiating first line therapy in advanced NSCLC can be significantly improved. By improving testing adherence, the most effective and appropriate therapy can be matched to the patient.

Novel Pegylated Interferon for the Treatment of Chronic Viral Hepatitis.

Ropeginterferon alfa-2b is a novel mono-pegylated and extra-long-acting interferon, being developed for the treatment of myeloproliferative neoplasm (MPN) and chronic viral hepatitis. It has a favorable pharmacokinetic profile and less frequent dosing schedule, i.e., once every two to four weeks, compared to conventional pegylated interferon products, which have multiple isomers and are administered weekly. It was approved for the long-term treatment of polycythemia vera, an MPN, and has been included in the NCCN clinical practice guidelines for this indication. Ropeginterferon alfa-2b has demonstrated efficacy and showed a favorable safety profile for the treatment of chronic viral hepatitis in several clinical studies. In this article, we review its pharmacokinetics and available clinical data and suggest that ropeginterferon alfa-2b administered once every two weeks can serve as a new treatment option for patients with chronic viral hepatitis, including chronic hepatitis B, C, and D.

Non-Small Cell Lung Cancer, Version 3.2022, NCCN Clinical Practice Guidelines in Oncology.

NCCN Clinical Practice Guidelines in Oncology (NCCN Guidelines) for Non-Small Cell Lung Cancer (NSCLC) provide recommended management for patients with NSCLC, including diagnosis, primary treatment, surveillance for relapse, and subsequent treatment. Patients with metastatic lung cancer who are eligible for targeted therapies or immunotherapies are now surviving longer. This selection from the NCCN Guidelines for NSCLC focuses on targeted therapies for patients with metastatic NSCLC and actionable mutations.

Impact of Allocation on Survival During Intermittent Chemotherapy Shortages: A Modeling Analysis.

Intermittent shortages of chemotherapeutics used to treat curable malignancies are a worldwide problem that increases patient mortality. Although multiple strategies have been proposed for managing these shortages (eg, prioritizing patients by age, scarce treatment efficacy per volume, alternative treatment efficacy difference), critical clinical dilemmas arise when selecting a management strategy and understanding its impact. We developed a model to compare the impact of different allocation strategies on overall survival during intermittent chemotherapy shortages and tested it using vincristine, which was recently scarce for 9 months in the United States. Demographic and treatment data were abstracted from 1,689 previously treated patients in our tertiary-care system; alternatives were abstracted from NCCN Clinical Practice Guidelines in Oncology for each disease and survival probabilities from the studies cited therein. Modeled survival was validated using SEER data. Nine-month shortages were modeled for all possible supply levels. Pairwise differences in 3-year survival and risk reductions were calculated for each strategy compared with standard practice (first-come, first-served) for each 50-mg supply increment, as were supply thresholds above which each strategy maintained survival similar to scenarios without shortages. A strategy prioritizing by higher vincristine efficacy per volume and greater alternative treatment efficacy difference performed best, improving survival significantly (P<.01) across 86.5% of possible shortages (relative risk reduction, 8.3%; 99% CI, 8.0-8.5) compared with standard practice. This strategy also maintained survival rates similar to a model without shortages until supply fell below 72.2% of the amount required to treat all patients, compared with 94.3% for standard practice. During modeled vincristine shortages, prioritizing patients by higher efficacy per volume and alternative treatment efficacy difference significantly improved survival over standard practice. This approach can help optimize allocation as intermittent chemotherapy shortages continue to arise.

Nonoperative Treatment of Large (5–7 cm), Node-Negative Non–Small Cell Lung Cancer Commonly Deviates From NCCN Guidelines

Optimal treatment of nonoperative patients with large, node-negative non-small cell lung cancer (NSCLC) is poorly defined. Current NCCN Clinical Practice Guidelines in Oncology (NCCN Guidelines) recommend definitive radiotherapy (RT) with or without sequential chemotherapy and do not include concurrent chemoradiotherapy (chemoRT) as a treatment option. In this study, we identified factors that predict nonadherence to NCCN Guidelines. Patients who received definitive RT for nonmetastatic, node-negative NSCLC with tumor size of 5 to 7 cm were identified in the National Cancer Database from 2004 through 2016. Patients were evaluated by RT type (stereotactic body RT [SBRT], hypofractionated RT [HFRT], or conventionally fractionated RT [CFRT]) and chemotherapy use (none, sequential, or concurrent with RT). Patients were classified as receiving NCCN-adherent (RT with or without sequential chemotherapy) or NCCN-nonadherent (concurrent chemoRT) treatment. Demographic and clinical factors were assessed with logistic regression modeling. Overall survival was evaluated with Kaplan-Meier, log-rank, and univariable/multivariable Cox proportional hazards regression analyses. Among 2,020 patients in our cohort, 32% received NCCN-nonadherent concurrent chemoRT, whereas others received NCCN-adherent RT alone (51%) or sequential RT and chemotherapy (17%). CFRT was most widely used (64% CFRT vs 22% SBRT vs 14% HFRT). Multivariable analysis revealed multiple factors to be associated with NCCN-nonadherent chemoRT: age ≤70 versus >70 years (odds ratio [OR] , 2.72; P<.001), treatment at a nonacademic facility (OR, 1.65; P<.001), and tumor size 6 to 7 cm versus 5 to 6 cm (OR, 1.27; P=.026). Survival was similar between the NCCN-nonadherent chemoRT and NCCN-adherent groups (hazard ratio, 1.00; P=.992) in multivariable analysis. A substantial proportion of inoperable patients with large, node-negative NSCLC are not treated according to NCCN Guidelines and receive concurrent chemoRT. Younger patients with larger tumors receiving treatment at nonacademic medical centers were more likely to receive NCCN-nonadherent therapy, but adherence to NCCN Guidelines was not associated with differences in overall survival.

Gastric Cancer, Version 2.2022, NCCN Clinical Practice Guidelines in Oncology.

Gastric cancer is the third leading cause of cancer-related deaths worldwide. Over 95% of gastric cancers are adenocarcinomas, which are typically classified based on anatomic location and histologic type. Gastric cancer generally carries a poor prognosis because it is often diagnosed at an advanced stage. Systemic therapy can provide palliation, improved survival, and enhanced quality of life in patients with locally advanced or metastatic disease. The implementation of biomarker testing, especially analysis of HER2 status, microsatellite instability (MSI) status, and the expression of programmed death-ligand 1 (PD-L1), has had a significant impact on clinical practice and patient care. Targeted therapies including trastuzumab, nivolumab, and pembrolizumab have produced encouraging results in clinical trials for the treatment of patients with locally advanced or metastatic disease. Palliative management, which may include systemic therapy, chemoradiation, and/or best supportive care, is recommended for all patients with unresectable or metastatic cancer. Multidisciplinary team management is essential for all patients with localized gastric cancer. This selection from the NCCN Guidelines for Gastric Cancer focuses on the management of unresectable locally advanced, recurrent, or metastatic disease.

Evaluation of the indication of BRCA1/2 genetic tests in Iranian women and acceptance rate of risk-reducing surgeries in BRCA mutation carriers.

BackgroundA higher risk for breast and ovarian cancer has been reported in BRCA carriers and prophylactic surgeries are proposed to reduce this risk. This retrospective cohort study has evaluated the indication of BRCA1/2 genetic tests in Iranian women and the rate of women's acceptance of prophylactic surgeries recommended by the surgeon.MethodsMedical records of 147 high‐risk women according to NCCN clinical practice guidelines who referred for BRCA mutations testing were assessed. Individual information, indications for BRCA1/2 genetic testing and their results, physician recommendations, and type of accepted surgery were registered. To evaluate the current status of women an active visit follow‐up every six months was conducted.ResultsThe mean age of women was 43.40 ± 10.94 and the median follow‐up time was 1.92 years. Genetic test results showed 49(33.3%) women were positive for either BRCA1/2 mutations. Although the occurrence of breast cancer younger than 40 was the most common indication for genetic tests (26.5%), positive breast cancer history in first‐degree relatives and two relatives younger than 50 was the most common indications with positive results. The rate of acceptance of prophylactic mastectomy and bilateral salpingo‐oophorectomy was (14.3% and 34.7%) in BRCA mutation carriers.ConclusionIf the onset of breast cancer at a young age (less than 40) will be the only indication for a BRCA analysis, the rate of a positive result (12.8%) is very low. Further studies are warranted to evaluate the age limit for genetic testing in our country. Prophylactic mastectomy acceptance is very low in BRCA1/2 carriers in our centers.

Kidney Cancer, Version 3.2022, NCCN Clinical Practice Guidelines in Oncology

The NCCN Guidelines for Kidney Cancer focus on the screening, diagnosis, staging, treatment, and management of renal cell carcinoma (RCC). Patients with relapsed or stage IV RCC typically undergo surgery and/or receive systemic therapy. Tumor histology and risk stratification of patients is important in therapy selection. The NCCN Guidelines for Kidney Cancer stratify treatment recommendations by histology; recommendations for first-line treatment of ccRCC are also stratified by risk group. To further guide management of advanced RCC, the NCCN Kidney Cancer Panel has categorized all systemic kidney cancer therapy regimens as "Preferred," "Other Recommended Regimens," or "Useful in Certain Circumstances." This categorization provides guidance on treatment selection by considering the efficacy, safety, evidence, and other factors that play a role in treatment selection. These factors include pre-existing comorbidities, nature of the disease, and in some cases consideration of access to agents. This article summarizes surgical and systemic therapy recommendations for patients with relapsed or stage IV RCC.

Implementation of INHERET, an Online Family History and Cancer Risk Interpretation Program for Primary Care and Specialty Clinics.

Individuals at increased risk for cancer are ascertained at low rates of 1% to 12% in primary care (PC). Underserved populations experience disparities of ascertainment, but data are lacking. INHERET is an online personal and family history tool to facilitate the identification of individuals who are eligible, according to guidelines, to be counseled on germline genetic testing and risk management. INHERET data entry uses cancer genetics clinic questionnaires and algorithms that process patient data through NCCN Clinical Practice Guidelines in Oncology and best practice guidelines. The tool was tested in silico on simulated and retrospective patients and prospectively in a pilot implementation trial. Patients in cancer genetics and in PC clinics were invited to participate via email or a card. Informed consent was completed online. INHERET aimed to integrate patient data by algorithms based on professional and best practice guidelines to elicit succinct, actionable recommendations that providers can use without affecting clinic workflow or encounter length. INHERET requires a 4th-grade reading level, has simple navigation, and produces data lists and pedigree graphs. Prospective implementation testing revealed understandability of 90% to 100%, ease of use of 85%, and completion rates of 85% to 100%. Physicians using INHERET reported no added time to their encounters when patients were identified for counseling. In a specialty genetics clinic, INHERET's data were input, on average, within 72 hours compared with 4 to 6 weeks through standard care, and the queue for scheduling patients decreased from 400 to fewer than 15 in <6 months. INHERET was found to be accessible for all education and age levels, except patients aged >70 years, who encountered more technical difficulties. INHERET aided providers in conveying high-risk status to patients and eliciting appropriate referrals, and, in a specialty clinic, it produced improved workflows and shortened queues.

Representation and Outcomes of Older Adults in Practice-Changing Oncology Trials in the Era of Novel Therapies: A Guideline Appraisal.

Older adults account for 70% of cancer-related deaths, but previous studies have shown that they are underrepresented in cancer clinical trials. We sought to analyze the representation and outcomes of older adults in trials conducted in the era of novel targeted therapy and immunotherapy. We searched the 2020 NCCN Clinical Practice Guidelines in Oncology and retrieved trials from the past 10 years leading to category 1 recommendations in the first-line metastatic setting for the 5 most common causes of cancer death. We categorized trials by cancer type, single-agent versus multiagent approach, and therapeutic class. We described the percentage of older adults (according to each trial's definition) and used a Mantel-Haenszel random-effects meta-analysis model to compare overall and progression-free survival by age. We identified 30 trials consisting of 24,416 patients. Across all trials, 44% of enrolled patients were older adults. Representation of older adults by cancer type within trials was 49% prostate cancer, 38% pancreatic cancer, 37% breast cancer, and 34% non-small cell lung cancer. Representation of older adults also varied by therapeutic class: 20% received immunotherapy, 44% received cytotoxic chemotherapy, 54% received targeted/hormonal therapy, and 34% received combination therapy (P<.001 for all comparisons). For each year since 2010, the percentage of older adults enrolled in trials increased by 1.9%, although this difference was not significant. We observed no difference in overall or progression-free survival between older and younger adults. In our analysis of practice-changing clinical trials, we found that 44% of clinical trial participants were older adults. Trials that included immunotherapy or a combination of therapeutic classes had a lower representation of older adults (<40%). We found that >40% of patients in practice-changing trials are older adults. Although they remain underrepresented in clinical trials compared with the general population, older adults in practice-changing trials seem to be better represented than in previously reported analyses of cooperative group trials.

Increasing Financial Payments From Industry to Medical Oncologists in the United States, 2014-2017.

Personal payments from the pharmaceutical industry to US physicians are common and are associated with changes in physicians' clinical practice and interpretation of clinical trial results. We assessed temporal trends in industry payments to oncologists, with particular emphasis on payments to authors of oncology clinical practice guideline and on payments related to immunotherapy drugs. We included US physicians with active National Plan and Provider Enumeration System records and demographic data available in the Centers for Medicare & Medicaid Services Physician Compare system who had a specialty type of medical oncology or general internal medicine. Medical oncologists serving on NCCN Clinical Practice Guidelines in Oncology (NCCN Guidelines) Panels were identified manually. Industry payments, and the subset associated with PD-1/PD-L1 drugs, were identified in Open Payments, the federal repository of all transactions of financial value from industry to physicians and teaching hospitals, from 2014 to 2017. There were 13,087 medical oncologists and 85,640 internists who received payments. The mean, annual, per-physician value of payments to oncologists increased from $3,811 in 2014 to $5,854 in 2017, and from $444 to $450 for internists; the median payment increased from $152 to $199 for oncologists and remained at $0 for internists. Oncologists who served on NCCN Guidelines Panels received a greater value in payments and experienced a greater relative increase: mean payments increased from $10,820 in 2014 to $18,977 in 2017, and median payments increased from $500 to $1,366. Among companies marketing PD-1/PD-L1 drugs, mean annual per-oncologist payments associated with PD-1/PD-L1 drugs increased from $28 to $773. Total per-oncologist payments from companies marketing PD-1/PD-L1 drugs experienced a 165% increase from 2014 to 2017, compared with a 31% increase among similar companies not marketing PD-1/PD-L1 drugs. Pharmaceutical industry payments increased for US oncologists from 2014 to 2017 more than for general internists. The increase was greater among oncologists contributing to clinical practice guidelines and among pharmaceutical companies marketing PD-1/PD-L1 drugs. The increasing flow of money from industry to US oncologists supports ongoing concern regarding commercial interests in guideline development and clinical decision-making.

Small Cell Lung Cancer, Version 2.2022, NCCN Clinical Practice Guidelines in Oncology.

The NCCN Clinical Practice Guidelines in Oncology (NCCN Guidelines) for Small Cell Lung Cancer (SCLC) provide recommended management for patients with SCLC, including diagnosis, primary treatment, surveillance for relapse, and subsequent treatment. This selection for the journal focuses on metastatic (known as extensive-stage) SCLC, which is more common than limited-stage SCLC. Systemic therapy alone can palliate symptoms and prolong survival in most patients with extensive-stage disease. Smoking cessation counseling and intervention should be strongly promoted in patients with SCLC and other high-grade neuroendocrine carcinomas. The "Summary of the Guidelines Updates" section in the SCLC algorithm outlines the most recent revisions for the 2022 update, which are described in greater detail in this revised Discussion text.

Clinical Characteristics and Late-Line Treatment Patterns of Patients with Chronic Myeloid Leukemia Who Received 2 Prior Lines of Tyrosine Kinase Inhibitor Therapy in US Community Oncology Practices

BACKGROUND: Current treatment guidelines recommend tyrosine kinase inhibitors (TKIs) as first-line and second-line treatment options for patients with chronic myeloid leukemia (CML). 1,2 However, approximately 20% of CML patients fail to respond to the first- and second-generation TKIs, and evidence-based guidelines for late-line treatment options after failure/intolerance to TKIs are limited. 3,4 Therefore, this study sought to describe the clinical characteristics and real-world treatment patterns of CML patients who received 2 prior lines of TKI therapy.METHODS: A retrospective cohort design was utilized to identify adult CML patients who initiated a new line of therapy (LOT) after 2 prior lines of TKI therapy between 4/2013 and 12/2020 in the Florida Cancer Specialists network's electronic health records (EHR) database. The index LOT date was the start date of a new CML treatment regimen in LOT≥3 after 2 prior lines of TKI therapy. Patients were followed until 1 of the following occurred: death, loss to follow-up (last structured activity in EHR), or end of study period (3/31/2021). Demographic and clinical characteristics were captured during the baseline period starting 3 months prior to the initial CML diagnosis until the index LOT date and included age, gender, race, Eastern Cooperative Oncology Group performance status (ECOG PS) and comorbidity burden. Treatment patterns of all available LOTs from initial CML diagnosis were investigated and the following metrics were captured: regimen details of systemic CML therapies, duration of LOT, treatment-free interval. This study was descriptive in nature and no inferential statistics were computed.RESULTS: A total of 157 patients who initiated a new CML treatment regimen in LOT≥3 after 2 previous lines of TKI therapy were included in this study. The median age of the study sample at initial CML diagnosis was 63.8 years, 57.3% of the sample were male, and 50.3% were White. At index LOT, 46.5% of the sample had an ECOG PS score of 0-1, 5.1% had ECOG PS score of 2-4, and 48.4% had an unknown ECOG PS score. The majority of the sample initiated the index LOT in LOT 3 (n=151; 96.2%) vs in LOT 4 (n=6; 3.8%). The median duration of the index LOT was 6.6 months with median follow-up from index LOT being 23.0 months. After 2 prior lines of TKI therapy, 93.0% of the sample continued on TKIs only, 1.3% initiated a non-TKI CML drug, and 5.7% received a combination of CML drugs. Dasatinib (31.2%) and imatinib (30.6%) were the most commonly used TKIs in the index LOT. There was significant variability in the treatment sequences across LOTs, however, 50.3% of the sample restarted the same TKI in their index LOT which had been used in a prior LOT. A total of 65 patients (41.4%) initiated a new LOT after the index LOT, and the treatment-free interval following the index LOT was 1.8 months, on average.CONCLUSIONS: The majority of the CML patients who received 2 prior lines of TKI therapy continue to cycle through additional LOTs containing TKIs, and half of the patients restart the same TKI used in a prior LOT. The findings of this study highlight the need for better novel therapies that can fill the treatment gap for CML patients who are refractory or intolerant to TKIs. REFERENCES1. Deininger MW, Shah NP, Altman JK, et al. Chronic Myeloid Leukemia, Version 2.2021, NCCN Clinical Practice Guidelines in Oncology. J Natl Compr Canc Netw. 2020;18(10):1385-1415.2. Hochhaus A, Saussele S, Rosti G, et al. Chronic myeloid leukaemia: ESMO Clinical Practice Guidelines for diagnosis, treatment and follow-up. Ann Oncol. 2017;28(suppl 4):iv41-iv51.3. Perrotti D, Jamieson C, Goldman J, et al. Chronic myeloid leukemia: mechanisms of blastic transformation. J Clin Invest. 2010;120(7):2254-2264.4. Cortes J, Lang F. Third-line therapy for chronic myeloid leukemia: current status and future directions. J Hematol Oncol. 2021;14(1):44. DisclosuresPatel: Novartis Pharmaceuticals Corporation: Research Funding. Raju: Xcenda LLC: Current Employment, Other: Xcenda LLC received research funding from Novartis Pharmaceuticals Corporation. Coutinho: Xcenda LLC: Current Employment, Other: Xcenda LLC received research funding from Novartis Pharmaceuticals Corporation. Maegawa: Novartis Pharmaceuticals Corporation: Current Employment, Current equity holder in publicly-traded company. Lunacsek: Xcenda LLC: Current Employment, Other: Xcenda LLC received research funding from Novartis Pharmaceuticals Corporation. Deyoung: Xcenda LLC: Current Employment, Other: Xcenda LLC received research funding from Novartis Pharmaceuticals Corporation. Iorga: Novartis Pharmaceuticals Corporation: Current Employment, Current equity holder in publicly-traded company. Cao: Novartis Pharmaceuticals Corporation: Current Employment, Current equity holder in publicly-traded company.

934 Biological mechanisms in the different etiologies of Merkel cell carcinoma patients: polyomavirus or UV exposure

BackgroundMerkel cell carcinoma (MCC) is a rare and aggressive skin cancer with neuroendocrine features, and it is associated with elevated mortality. The pathogenesis is associated with presence of clonally integrated Merkel cell polyomavirus (MCPyV) or ultraviolet light (UV) exposure.1 The MCPyV causes up to 80% of MCC tumors in North America and Europe.2–4 Recently immunotherapy is having good results,5 the phase 2 trial JAVELIN Merkel 200 indicated that treatment with Avelumab (PDL1 inhibitor) in patients with metastatic MCC pre-treated have a meaningful long-term survival outcomes respect chemotherapy. Moreover, ORRs were highest in patients with high TMB that were also MCPyV−, PD-L1+ or had a greater CD8+ T cell density at the invasive margin.6 In this study, we investigated the biological signatures in patients with MCPyV or not.MethodsFrom April 2011 to June 2018, we collected retrospectively 50 FFPE (Formalin-Fixed Paraffin-Embed) from 37 patients with metastatic MCC and 13 tissues from a secondary metastatic site. All patients have appropriately signed informed consent. We performed an immunohistochemistry assays (IHC) for MCPyV and PDL1. In addition, through the NanoString GeoMx DSP (Digital Spatial Profiling), we analysed 11 patients (6 MCPyV+; 5 MCPyV-) with cutaneous metastasis using a 44-plex antibody cocktail. For each slide we selected three different areas: Intratumoral, extratumoral and tumour border, in each area we selected CD4+ and CD8+ cells in 4 different ROIs (Region of Interest). Statistical analysis was performed via Bonferroni correction, P&lt; 0.05 was considered statistically significant for median stratification.ResultsThe DSP analysis showed that the tumour border cells have an overexpression of IDO respect intratumoral area (adj. p&lt;0.01). Instead, extratumoral area of MCPyV- patients have a higher expression of B7-H3 respect MCPyV+ as well as FOXP3 is higher in the tumour border of MCPyV+ patients and EpCAM in the intratumoral area (p&lt;0.05). PDL1 is overexpressed in MCPyV+ CD4+ cells respect CD8+ (p&lt;0.05). The IHC assay shown that viral status does not change in multiple metastases and PDL1 is elevated in the tumour border (p&lt;0.05).ConclusionsIn this retrospective study, our preliminary data shown that tumour edge have an important role in the modulations of immune infiltrate and patients with Merkel cell polyomavirus could have a different pathway of immunosuppression compared to patients with non-virus related etiology. Further investigations are needed to get additional information.AcknowledgementsThe study was supported by the Institutional Project ”Ricerca Corrente” of Istituto Nazionale Tumori IRCCS Fondazione ”G. Pascale” of Napoli, Italy.ReferencesKaae J, Hansen AV, Biggar RJ, et al. Merkel cell carcinoma: incidence, mortality, and risk of other cancers. J Natl Cancer Inst 2010 June 2;102(11):793–801.Feng H, Shuda M, Chang Y, et al. Clonal integration of a polyomavirus in human Merkel cell carcinoma. Science 2008 February 22;319(5866):1096–100.Garneski KM, Warcola AH, Feng Q, et al. Merkel cell polyomavirus is more frequently present in North American than Australian Merkel cell carcinoma tumors. J Invest Dermatol 2009 January;129(1):246–8.Goh G, Walradt T, Markarov V, et al. Mutational landscape of MCPyV-positive and MCPyV-negative Merkel cell carcinomas with implications for immunotherapy. Oncotarget 2016 January 19;7(3):3403–15.Bichakjian CK, Olencki T, Aasi SZ, et al. Merkel cell carcinoma, version 1.2018, NCCN Clinical Practice Guidelines in Oncology. J Natl Compr Canc Netw 2018 June;16(6):742–774.D’Angelo SP, Bhatia S, Brohl AS, et al. Avelumab in patients with previously treated metastatic Merkel cell carcinoma: long-term data and biomarker analyses from the single-arm phase 2 JAVELIN Merkel 200 trial. J Immunother Cancer 2020 May;8(1):e000674.Ethics ApprovalThe study was approved by internal ethics board of the Istituto Nazionale Tumori IRCCS Fondazione ”G. Pascale” of Napoli Italy, approval number of registry 33/17 OSS.ConsentWritten informed consent was obtained from the patient for publication of this abstract and any accompanying images. A copy of the written consent is available for review by the Editor of this journal.

Recommendations for Managing Adults With Histiocytic Neoplasms: New NCCN Guidelines

The histiocytoses, a group of clonal and reactive conditions, arise from monocytic macrophage or dendritic cell lineages. The current NCCN Clinical Practice Guidelines in Oncology (NCCN Guidelines) for Histiocytic Neoplasms reflect the most up-to-date, evidence-based data relating to the evaluation and management of this disease. Specifically, the guidelines focus on adult Langerhans cell histiocytosis, Erdheim-Chester disease, and Rosai-Dorfman disease. Because these disorders are rare, challenges have arisen regarding clinical suspicion, histologic diagnosis, treatment, and molecular subtyping. Future versions of the NCCN Guidelines will address the diagnosis and management of pediatric patients, as well as malignant histiocytosis.