BRAF V600E Status Research Articles

Cost effectiveness analysis of BRAFV600E testing for low-risk papillary thyroid microcarcinomas.

Given the good prognosis of low-risk papillary thyroid microcarcinomas (lrPTMCs), accurate risk stratification is valuable to optimize management: active surveillance (AS) vs. hemithyroidectomy (HT). BRAFV600E positive lrPTMC is associated with increased recurrence risk; hence, AS was suggested for mutation-negative lrPTMC. This study aims to evaluate the cost-effectiveness of BRAFV600E testing for lrPTMC. Decision tree cost-effectiveness analytic model. We performed a cost-effectiveness analysis of the management strategies for lrPTMCs: AS, HT, and BRAFV600E genetic testing (GT), in which treatment pathways were determined by BRAFV600E status. Data on probabilities and complications were derived from current literature. One- and two-way sensitivity analyses were conducted to ascertain model robustness. Our model found GT as the cost-effective strategy, providing an additional 0.35 QALYs and an additional cost of $902 with an Incremental Cost-effectiveness ratio of $2542 compared to AS. In contrast, surgical intervention showed a lower utility with an increased cost of $381, positioning GT as the preferred strategy. Sensitivity analysis identified age at diagnosis as the most influential factor for cost-effectiveness between AS and GT; younger patients exhibited a lower ICER, indicating greater cost savings per QALY, till up to age 48years, where AS becomes favorable. GT consistently outperformed QALY gains across varying incidences of BRAFV600E positivity tumors. In conclusion, this study demonstrates the economic and clinical advantages of incorporating BRAFV600E genetic testing in the management of lrPTMCs. Our model supports further real-life studies of BRAFV600E testing for lrPTMCs.

An Automated Real-Time PCR Assay versus Next-Generation Sequencing in the Detection of BRAF V600 Mutations in Melanoma Tissue Samples.

Next-generation sequencing (NGS) is the most commonly used method for determining BRAF mutational status in patients with advanced melanoma. Automated PCR-based methods, such as the IdyllaTM system, are increasingly used for mutation diagnostics, but it is unclear what impact the choice of diagnostic method has on the management of melanoma. To compare the concordance rate of BRAF V600 mutational analysis using IdyllaTM and NGS and to analyze the technical and clinical turnaround time. The clinical relevance is compared by analyzing the impact on the treatment decision. In this monocentric prospective cohort study, the BRAF mutation status of 51 patients was determined using both methods in parallel. BRAF V600 mutation was detected in 23/51 cases (45%). IdyllaTM showed a 100% concordant result with a faster turnaround time (0.2 days) compared to NGS (12.2 days). In general, less tumor material was required for IdyllaTM than for NGS. Most patients received immunotherapy as a first-line therapy regardless of the BRAF V600 status. IdyllaTM testing proved to be a reliable and rapid alternative to NGS in the determination of BRAF V600 mutation. Although BRAF. status was available earlier, this had no influence on the treatment decision in most cases.

Distinct transcriptional and prognostic impacts of TERT promoter mutations C228T and C250T in papillary thyroid carcinoma.

TERT promoter mutations C228T and C250T are associated with disease aggressiveness and poor clinical outcomes in patients with papillary thyroid carcinomas. However, very little is known about the transcriptional consequences of these mutations and whether they both carry similar oncogenic potential. Here we characterized the transcriptional disturbances and clinical outcomes associated with the presence of each of these two mutations using data derived from The Cancer Genome Atlas. We observed that tumors harboring the C228T mutation (n = 27) exhibited a 16-fold increase in TERT mRNA levels (P = 5.3 × 10-42), whereas C250T tumors (n = 8) showed only a two-fold increase in expression (P = 0.034). The C228T mutation was associated with the activation of signaling pathways controlling the cell cycle, cellular division, and extracellular matrix degradation. Univariate analysis demonstrated that the C228T mutation was associated with older age at diagnosis, large tumor size, lymph node invasion, and distant metastases at diagnosis. The C228T mutation was also associated with worse progression-free interval (PFI) in comparison to WT tumors (HR = 5,04; P < 0.001). This association remained significant in a multivariate analysis (HR = 3.74, P = 0.003) adjusting for BRAF-V600E status and ATA risk group. Our data indicate that TERT promoter mutations C228T and C250T have distinct transcriptional consequences in papillary thyroid carcinoma (PTC), suggesting a greater oncogenic potential for the C228T mutation. TERT promoter mutation C228T may be a useful prognostic marker to identify patients at high risk of distant recurrence. Clinical data for the C250T mutation is still limited, with no evidence up to date to confirm its prognostic significance.

Apoptosis Pathway-Associated Proteins Are Frequently Expressed in Melanoma: A Study of 32 Cases With Focus on Acral Lentiginous Melanoma.

Acral lentiginous melanoma (ALM) is an aggressive type of cutaneous melanoma (CM) that arises on palms, soles, and nail units. ALM is rare in White population, but it is relatively more frequent in dark-skinned populations. There is an unmet need to develop new personalized and more effective treatments strategies for ALM. Increased expression of antiapoptotic proteins (ie, BCL2, MCL1) has been shown to contribute to tumorigenesis and therapeutic resistance in multiple tumor types and has been observed in a subset of ALM and mucosal melanoma cell lines in vivo and in vitro. However, little is known about their expression and clinical significance in patients with ALM. Thus, we assessed protein expression of BCL2, MCL1, BIM, and BRAF V600E by immunohistochemistry in 32 melanoma samples from White and Hispanic populations, including ALM and non-ALM (NALM). BCL2, MCL1, and BIM were expressed in both ALM and NALM tumors, and no significant differences in expression of any of these proteins were detected between the groups, in our relatively small cohort. There were no significant associations between protein expression and BRAF V600E status, overall survival, or ethnicity. In summary, ALM and NALM demonstrate frequent expressions of apoptosis-related proteins BCL2, MCL1, and BIM. Our findings suggest that patients with melanoma, including ALM, may be potential candidates for apoptosis-directed therapies.

TERT RNAscope analysis of sub-centimetric papillary thyroid carcinomas and synchronous lymph node metastases.

Sub-centrimetric papillary thyroid carcinomas usually have a good prognosis with a cancer specific survival of > 99%, however in up to 65% of patients, lymph node metastases can be observed. Molecular alterations in BRAF, TERT and TP53 are associated with worse clinicopathological outcome in patients with papillary thyroid carcinoma. Twenty-two cases of papillary thyroid carcinomas measuring ≤ 1cm with synchronous lymph node metastases were examined regarding morphological patterns and immunohistochemical status of p53, Ki-67, and BRAF V600E status. TERT RNA expression in lymph node metastases were evaluated by RNAScope®. Morphological patterns were heterogeneous in both primary tumors and lymph node metastases. Proliferation indices measured by Ki-67 were low. Both primary and lymph node metastases were wild type for p53 by immunohistochemical analysis. No lymph node metastasis showed TERT expression by RNAScope®. Our data indicate that TERT expression is not involved in the development early lymph node metastasis in patients with sub-centimetric PTC.

Retrospective study of BRAFV600E mutation and CT features of papillary thyroid carcinoma.

This study aimed to examine the correlation between BRAFV600E status and computed tomography (CT) imaging characteristics in papillary thyroid carcinoma (PTC) and determine if suspicious CT imaging features could predict BRAFV600E status. This retrospective study included patients with pathologically confirmed PTC at the Department of Thyroid Surgery of Zhongshan Hospital, Xiamen University, between July 2020 and June 2022. We compared the clinicopathologic factors and CT findings of nodules with and without the mutation, and the multiple logistical regression test was used to determine independent parameters of the BRAFV600E mutation. This study included 381 patients with PTC, among them, BRAFV600E mutation was detected in 314 patients (82.4%). Multivariate logistic regression analysis showed that gender (OR = 0.542, 95% CI [0.296-0.993], P = 0.047) and shape (OR = 0.510, 95% CI [0.275-0.944], P = 0.032) were associated with BRAFV600E mutation. Compared to BRAFV600E mutation-negative, BRAFV600E-positive PTC lesions were more likely to be found in female patients and were characterized by irregular shape. However, the CT imaging finding is not enough to predict BRAFV600E status, but an indication.

Circulating tumor DNA (ctDNA) dynamics in patients with colorectal cancer (CRC) with molecular residual disease: Updated analysis from GALAXY study in the CIRCULATE-JAPAN.

6 Background: Our previous analysis of data from the prospective, observational GALAXY study (UMIN000039205) reported post surgical detection of molecular residual disease (MRD) to be prognostic of patient (pt) outcomes and the most significant risk factor for recurrence regardless of BRAF V600E status. Here, we present an updated analysis and correlation of ctDNA dynamics with outcomes in pts with radically resected, stage II-IV CRC from the GALAXY study. Methods: A personalized, tumor-informed assay (Signatera, Natera, Inc.) was used for the detection and quantification of ctDNA in serial plasma samples collected at 1, 3, 6, 9, 12, 18, and 24 months post surgery until recurrence. CT scans of chest/abdomen/pelvis were conducted every 6 months. Post curative-intent surgery, pts underwent either treatment with adjuvant chemotherapy (ACT; N = 1,000) or observation (N = 1,518). The primary endpoint was disease-free survival (DFS), defined as the time between the date of surgery and date of detection of relapse/death due to any cause. Results: Of the 3,034 CRC pts enrolled between May 2020 and November 2022 in GALAXY study, 2,518 pts met the inclusion criteria and were analyzed in this substudy. The median follow-up was 16.3 months (range 0.1-37 mos). During the post-op MRD window, ctDNA results were available for 2,093 pts, 309 (14.8%) of whom were ctDNA+ and 1,784 (85.2%) were ctDNA-. Pts who were ctDNA+ during the MRD window (MRD+) had a significantly inferior DFS compared to MRD- pts (HR: 15.75, 95%CI: 12.59-19.68, p &lt; 0.0001). Within the MRD+ group, a landmark analysis of ctDNA dynamics from MRD detection to 3-month time point revealed that pts who remained ctDNA+ were over 5-times more likely to recur compared to those who had ctDNA clearance (HR: 5.4, 95%CI: 3.58-7.67%, p &lt; 0.0001). Among the 309 MRD+ pts, 181 received adjuvant therapy, 72.9% (132/181) of whom had ctDNA clearance. Notably, for those pts with subsequent ctDNA time points available, 68/126 (54%) had sustained clearance vs. 58/126 (46%) pts eventually returned ctDNA+. Pts with sustained clearance had remarkably better outcomes compared to those with transient ctDNA clearance (HR: 32.57, 95% CI: 9.94-106.76, p &lt; 0.0001). Furthermore, we observed that among MRD+ pts treated with ACT, a 50% or greater decrease in ctDNA levels (mean tumor molecules/mL) at 6 months was associated with better DFS compared to pts with &lt;50% decrease or increase in ctDNA levels (HR: 2.39, 95% CI: 1.32-4.34, p = 0.004). Conclusions: ctDNA-based detection of MRD as well as ctDNA dynamics in response to ACT were highly prognostic of pt outcomes. Ongoing randomized VEGA and ALTAIR studies in the CIRCULATE-Japan will establish clinical utility of ctDNA-guided adjuvant treatment. Clinical trial information: UMIN000039205.

Colorectal cancer metastatic dMMR immuno-therapy (COMMIT) study: A randomized phase III study of atezolizumab (atezo) monotherapy versus mFOLFOX6/bevacizumab/atezo in the first-line treatment of patients (pts) with deficient DNA mismatch repair (dMMR) or microsatellite instability-high (MSI-H) metastatic colorectal cancer (mCRC)—NRG-GI004/SWOG-S1610.

TPS231 Background: Approximately 45% of dMMR/MSI-H mCRC in the immunotherapy arm progressed at 12 mos (KEYNOTE 177). We hypothesize that dMMR/MSI-H mCRC pts may be more effectively treated with the combination of PD-1/PD-L1 (PD-1) pathway blockade and mFOLFOX6/bevacizumab (bev) rather than with anti-PD-L1 therapy (atezo) alone. Preclinical work demonstrated synergistic effects between anti-PD-1/anti-VEGF as well as between oxaliplatin/anti-PD-1 in murine CRC models, and phase II data showed activity of anti-PD-1/anti-VEGF in chemotherapy refractory colon cancer. Upon AtezoTRIBE subgroup analysis of the 8 pts with dMMR mCRC treated with FOLFOXIRI+bev+atezo, median PFS was not reached, with the first patient having progression ~16 mos. Additionally, in other solid tumor malignancies, anti-PD-1 plus anti-VEGFr (i.e., HCC and RCC) as well as anti-PD-1 plus chemotherapy (i.e., gastroesophageal and lung cancers) combinations are standard first-line treatments. Methods: This two-arm prospective phase III open-label trial randomizes (1:1) mCRC dMMR/MSI-H to atezo monotherapy v mFOLFOX6/bev+atezo combination. Key inclusion criteria have been simplified on recent amendments to better mirror clinical practice for pts receiving mFOLFOX6/bev+/-atezo: One cycle of FOLFOX or CAPOX, with or without bev (or biosimilar) prior to enrollment allowed, dMMR tumor determined by local CLIA-certified IHC assay (MLH1/MSH2/MSH6/PMS2) or MSI-H by local CLIA-certified PCR or NGS panel; pts with total bilirubin ≤4.0 x ULN; duration of therapy for up to two years for both arms; imaging frequency on post-treatment follow up have been reduced; as has measurable disease per RECIST. The primary endpoint is PFS. Assuming the atezo monotherapy control arm has a 48% PFS at 24 mos as assessed by site investigator, we have 80% power to detect a hazard ratio of 0.6 (equivalent to 64.4% PFS at 24 mos) with alpha 0.025 one-sided. Stratification factors include BRAFV600E status, metastatic site, and prior adjuvant CRC therapy. Secondary endpoints include overall survival objective response rate, safety profile, disease control rate, and duration of response. Archived tumor tissue and blood samples will be collected for correlative studies. Harmonization of translational analyses is planned between GI004 (COMMIT) and A021502 (ATOMIC). The sample size has been modified with the accrual goal of 120 patients randomized between the two immunotherapy arms needed for study completion. Enrollment actively continues. Support: U10CA180868, -180822, -180888, UG1CA189867, U24CA196067; Genentech, Inc. Clinical trial information: NCT02997228 .

Phase 2 Trial of Single-Agent Cobimetinib for Adults with Histiocytic Neoplasms

Background: Histiocytic neoplasms (HN) are clonal hematopoietic disorders characterized by diverse mutations in the mitogen-activated protein kinase (MAPK) pathway. BRAF inhibition is highly effective for patients with HN harboring the BRAFV600E mutation, and implementation of BRAF inhibitors transformed management of BRAFV600E-mutated Erdheim-Chester disease (ECD) and Langerhans cell histiocytosis (LCH). No standard or approved therapies existed, however, for patients with HN lacking the BRAFV600E mutation. Efficacy of mitogen-activated protein kinase (MEK) inhibition for HN harboring various MAPK pathway mutations has been observed in case reports and series. We present here results from 26 patients treated in a phase 2 trial of single-agent cobimetinib for adults with HN (NCT02649972). The data were submitted to the Food and Drug Administration (FDA) in a supplemental new drug application for cobimetinib, and FDA approval was granted in October, 2022. Methods: This is an open-label phase 2 trial of cobimetinib 60mg daily for patients with (1) BRAFV600-wildtype (wt) histiocytosis or (2) BRAFV600-mutant histiocytosis intolerant or without access to BRAF inhibitor therapy. Eligible patients were age 16 or older, had histologic confirmation of HN diagnosis, ECOG 0 to 3, multi-system HN or HN refractory to conventional (i.e. chemotherapeutic or immunosuppressive) therapy or single-system HN deemed unlikely to benefit from conventional therapy, and with disease measurable by positron emission tomography (PET) Response Criteria (PRC). Patients were eligible with any tumor mutation or with no identified tumor mutation. The primary endpoint was overall response rate (complete metabolic response + partial metabolic response; ORR) by PRC. Secondary endpoints included safety (CTCAE 4.0), duration of response (DoR) and progression-free survival (PFS) as determined by modified PERCIST, overall survival (OS), and response rate by RECIST. Data cut-off was March 28, 2019 for efficacy evaluation, and safety follow-up cut-off was September 28, 2019. Results: Twenty-six patients (13 ECD, with Rosai-Dorfman disease [RDD], 4 with LCH, 2 with juvenile xanthogranuloma [JXG], 3 with mixed histiocytosis) with a median age of 50.5 were analyzed. Six patients had BRAFV600E-mutant disease, one of these with additional mutations in KRAS and NRAS. Of the remaining 20, 15 had non-BRAFV600 MAPK pathway mutations (4 KRAS [one of them with ARAF mutation as well], 6 MEK1, 1 MEK2, 1 RAF1, 1 ARAF, 2 non-V600 BRAF mutations, and 5 had no mutation identified). Twenty-six patients were evaluable for safety, 24 for PRC, 19 for RECIST. Response rates are listed in Table 1 and PRC responses are presented in Figure 1. The ORR by PRC was 83.3% (95% CI 62.62-95.26), in the PRC-evaluable population. Responses were observed across MAPK mutations, histiocytosis subtypes and tumor genotypes. By BRAFV600 status, in PRC-evaluable population, the ORR for BRAFV600E-mutant disease was 100% (95% CI 47.82-100), and for BRAFV600-wt disease was 78.9% (95% CI 54.43-93.95). Median DoR was 31.1 months (95% CI 16.8-NE) in the PRC-evaluable population. ORR by RECIST was 63.2% (95% CI 38.36-83.71), in the RECIST-evaluable population. Three patients died on study, none related to cobimetinib. Grade 3 or 4 toxicities in &amp;gt;10% of patients included decreased lymphocyte count (19%), increased blood creatine phosphokinase (12%), decreased ejection fraction (12%), hypokalemia (12%), hyponatremia (12%), acute kidney injury (12%) and dyspnea (12%). Conclusions: Cobimetinib demonstrates robust efficacy in HN irrespective of underlying MAPK pathway mutation, including BRAF-wt and BRAFV600-mutant HN. Safety of cobimetinib in this patient population was consistent with the known safety profile.

BRAF V600E mutation in papillary thyroid microcarcinoma: is it a predictor for the prognosis of patients with intermediate to high recurrence risk?

The BRAFV600E mutation is the universal genetic mutation in papillary thyroid microcarcinoma (PTMC). The present study is to estimate the role of the BRAFV600E mutation in the clinical outcome of PTMC with intermediate to high recurrence risk after radioactive iodine (RAI) therapy, which is considered to be an indolent tumor. We conducted a single-center retrospective study. Between May 2016 and March 2019, PTMC patients with known BRAFV600E status who received RAI therapy were reviewed at the Second Hospital of Shandong University. Treatment and follow-up were defined according to criteria used in the 2015 ATA guidelines. The association between the BRAFV600E mutation and clinicopathological characteristics, response to RAI therapy, and recurrence after a period of follow-up were analyzed. Propensity score matching (PSM) and logistic regression were used to control confounding variables. Of the 322 patients with intermediate to high recurrence risk in PTMC, the mean age of the patients were 43.7 ± 12.2 years, and 72.1% were women. BRAFV600E mutation was found in 64.9% (209/322). After PSM, 112 pairs of patients were matched, and except for multifocality (P = 0.001), extrathyroidal invasion (P = 0.003) and tumor size (P = 0.03), there was no significant difference in all baseline characteristics between the two groups. An excellent response (ER) to RAI therapy was observed in 273 patients (84.7%). At the end of the study, 17(5.2%) and 6(1.8%) patients showed structural incomplete response (SIR) and biochemical incomplete response (BIR) status. The proportion of patients who achieved ER status in the BRAFV600E mutation positive and negative groups was 86.6% and 81.4%, respectively. Kaplan-Meier analyses showed that the BRAFV600E mutation was not related to lower ER reached time. The median follow-up was 51 months. We found the BRAFV600E mutation was associated with multifocality, extrathyroidal invasion, and tumor size in papillary thyroid microcarcinoma. However, the BRAFV600E mutation had no significant association with clinical outcomes in patients with intermediate to high recurrence risk after RAI therapy. Furthermore, the extra-thyroid uptake results and distant metastasis had been proven to be independent factor predicting the clinical response. ChiCTR2200062911.

Molecular Features of Resected Melanoma Brain Metastases, Clinical Outcomes, and Responses to Immunotherapy

Central nervous system (CNS)-penetrant systemic therapies have significantly advanced care for patients with melanoma brain metastases. However, improved understanding of the molecular landscape and microenvironment of these lesions is needed to both optimize patient selection and advance treatment approaches. To evaluate how bulk and single-cell genomic features of melanoma brain metastases are associated with clinical outcome and treatment response. This cohort study analyzed bulk DNA sequencing and single nuclear RNA-sequencing data from resected melanoma brain metastases and included 94 consecutive patients with a histopathologically confirmed diagnosis of melanoma brain metastasis who underwent surgical resection at a single National Comprehensive Cancer Network cancer center in San Francisco, California, from January 1, 2009, to December 31, 2022. A Clinical Laboratory Improvement Amendments-certified targeted sequencing assay was used to analyze tumor resection specimens, with a focus on BRAF V600E alteration. For frozen pathologic specimens from CNS treatment-naive patients undergoing surgical resection, commercial single nuclear RNA sequencing approaches were used. The primary outcome was overall survival (OS). Secondary outcomes included CNS progression-free survival (PFS), microenvironmental composition with decreased T-cell and macrophage populations, and responses to immunotherapy. To correlate molecular status with clinical outcome, Kaplan-Meier survival analysis of 94 consecutive patients (median age, 64 years [range, 24-82 years]; 70 men [74%]) with targeted BRAF alteration testing showed worse median intracranial PFS (BRAF variant: 3.6 months [IQR, 0.1-30.6 months]; BRAF wildtype: 11.0 months [IQR, 0.8-81.5 months]; P < .001) and OS (BRAF variant: 9.8 months [IQR, 2.5-69.4 months]; BRAF wildtype: 23.2 months [IQR, 1.1-102.5 months]; P = .005; log-rank test) in BRAF V600E variant tumors. Multivariable Cox proportional hazards regression analysis revealed that BRAF V600E status was an independent variable significantly associated with both PFS (hazard ratio [HR], 2.65; 95% CI, 1.54-4.57; P < .001) and OS (HR, 1.96; 95% CI, 1.08-3.55; P = .03). For the 45 patients with resected melanoma brain metastases undergoing targeted DNA sequencing, molecular classification recapitulated The Cancer Genome Atlas groups (NRAS variant, BRAF variant, NF1 variant, and triple wildtype) with no subtype enrichment within the brain metastasis cohort. On a molecular level, BRAF V600E variant lesions were found to have a significantly decreased tumor mutation burden. Moreover, single nuclear RNA sequencing of treatment-naive BRAF V600E variant (n = 3) brain metastases compared with BRAF wildtype (n = 3) brain metastases revealed increased immune cell populations in BRAF wildtype tumors (mean [SD], 11% [4.1%] vs 3% [1.6%] CD45-positive cells; P = .04). Survival analysis of postoperative immunotherapy responses by BRAF status revealed that BRAF wildtype lesions were associated with a response to checkpoint inhibition (median OS: with immunotherapy, undefined; without immunotherapy, 13.0 months [range, 1.1-61.7 months]; P = .001; log-rank test) while BRAF variant lesions (median OS: with immunotherapy, 9.8 months [range, 2.9-39.8 months]; without immunotherapy, 9.5 months [range, 2.5-67.2 months]; P = .81; log-rank test) were not. This molecular analysis of patients with resected melanoma brain metastases found that BRAF V600E alteration is an important translational biomarker associated with worse clinical outcomes, differential microenvironmental composition, and benefit from immunotherapy. Patients with BRAF V600E variant melanoma brain metastases may thus benefit from alternative CNS-penetrant systemic regimens.

Postoperative circulating tumor DNA-based molecular residual disease in patients with BRAF V600E and MSI-H colorectal cancer: Updated results from GALAXY study in the CIRCULATE-Japan.

32 Background: Postoperative circulating tumor DNA (ctDNA)-based molecular residual disease (MRD) is reported to be associated with a high risk of recurrence. Here, we present an updated analysis of MRD detection and correlations with BRAF and MSI status in radically resected, stage II-IV colorectal cancer (CRC) from the observational GALAXY study (UMIN000039205). Methods: Serial ctDNA was analyzed using personalized tumor-informed assay (Signatera bespoke multiplex-PCR NGS assay) at 1 (4-week MRD time point), 3, 6, 9, 12, 18, and 24 months after surgery or until recurrence (whichever comes first). CT scans were conducted every 6 months. BRAF and MSI status were determined by central assessment until September 2021 and per the standard of care after October 2021. The primary endpoint was disease-free survival (DFS), defined as the time between the date of surgery and date of diagnosis with relapse or death due to any cause. Results: Among 3,615 CRC patients (pts) who were enrolled between May 2020 and April 2022 in GALAXY study, 2,083 pts that met the inclusion criteria were analyzed. The median follow-up period was 16.3 months. Of 2,083 pts included in the analysis, 60 pts (2.9%) had BRAF V600E mutant and MSS tumors, 100 pts (4.8%) had BRAF wt and MSI-H tumors, and 115 patients (5.5%) had BRAF V600E mutant and MSI-H tumors. In the overall population, 286 (14%) were ctDNA-positive at the 4-week MRD time point and 1,797 (86%) were ctDNA-negative. Pts with ctDNA-positivity at the 4-week demonstrated inferior DFS and were 12 times more likely to recur, compared to ctDNA-negative pts (HR: 12, 95%CI: 9.1-15%; p&lt;0.001). Pts with BRAF wt and MSI-H tumors had significantly better DFS compared to pts with BRAF wt and MSS tumors (HR: 4.14, 95 %CI: 1.3-12.9, p=0.015). Pts with BRAF V600E mutant and MSI-H tumors had significantly better DFS compared to pts with BRAF wt and MSS tumors (HR: 4.80, 95 %CI: 1.5-15, p=0.007). On the other hand, ctDNA-positivity was associated with significantly shorter DFS in pts with BRAF V600E mutant and MSS tumors (HR: 2.33, 95%CI: 1.03-5.3, p=0.043) and BRAF V600E mutant and MSI-H tumors (HR:7.54, 95%CI:2.37-24, p&lt;0.001) compared to pts with BRAF wt and MSS tumors. Multivariate analysis in DFS showed that ctDNA positivity was significantly associated with poor prognosis (HR: 11.68, 95%CI: 8.61-15.85, p&lt;0.001), outperforming other clinicopathologic factors such as BRAF and MSI status. Conclusions: ctDNA status at the postoperative MRD time point is the most prognostic risk factor of DFS regardless of BRAF V600E or MSI-H status. Pts with positive postoperative ctDNA should be examined carefully due to a high risk of recurrence. ctDNA-guided adjuvant strategies will further be established by the ongoing randomized VEGA and ALTAIR studies in CIRCULATE-Japan. Clinical trial information: UMIN000039205 .

Predictors and a prediction model for positive fine needle aspiration biopsy in C-TIRADS 4 thyroid nodules.

To screen out the predictors and establish a prediction model of positive fine needle aspiration biopsy (FNAB) in the Chinese Guidelines for Malignant Risk Stratification of Thyroid Nodule Ultrasound (C-TIRADS) 4 thyroid nodules, and this nomogram can help clinicians evaluate the risk of positive FNAB and determine if FNAB is necessary. We retrospectively analyzed data from 547 patients who had C-TIRADS 4 thyroid nodules and underwent fine-needle aspiration biopsy (FNAB) at the Second Affiliated Hospital of Chongqing Medical University between November 30, 2021 and September 5, 2022. Patients who met our inclusion criteria were divided into two groups based on positive or negative FNAB results. We compared their ultrasound (US) features, BRAF V600E status, thyroid function, and other general characteristics using univariate and multivariate logistic regression analyses to identify independent predictors. These predictors were then used to construct a nomogram. The calibration plot, area under the curve (AUC), and decision curve analysis were employed to evaluate the calibration, discrimination, and clinical utility of the prediction model. Out of 547 patients, 39.3% (215/547) had a positive result on fine-needle aspiration biopsy (FNAB), while 60.7% (332/547) had a negative result. Univariate logistic regression analysis revealed no significant differences in TPOAb, TgAb, TSH, Tg, nodule location, sex, or solid status between the two groups (P>0.05). However, age, nodule size, internal or surrounding blood flow signal, microcalcifications, aspect ratio, morphology, and low echo showed significant differences (P<0.05). Multivariate logistic regression analysis was conducted to explore the correlation between potential independent predictors. The results showed that only age (OR=0.444, 95% Cl=0.296~0.666, P<0.001), low echo (OR=3.549, 95% Cl=2.319~5.432, P<0.001), microcalcifications (OR=2.531, 95% Cl=1.661~3.856, P<0.001), aspect ratio (OR=3.032, 95% Cl=1.819~5.052, P<0.001), and morphology (OR=2.437, 95% Cl=1.586~3.745, P<0.001) were independent predictors for a positive FNAB. These variables were used to construct a prediction nomogram. An ROC curve analysis was performed to assess the accuracy of the nomogram, and AUC=0.793, which indicated good discrimination and decision curve analysis demonstrated clinical significance within a threshold range of 14% to 91%. In conclusion, 5 independent predictors of positive FNAB, including age (≤45 years old), low echo (yes), microcalcifications (yes), aspect ratio (>1) and morphology (irregular), were identified. A nomogram was established based on the above 5 predictors, and the nomogram can be used as a complementary basis to help clinicians make decisions on FNAB of C-TI-RADS 4 thyroid nodules.

MRI characteristics predict BRAF V600E status in gangliogliomas and pleomorphic xanthoastrocytomas and provide survival prognostication.

BRAF V600E mutation is a common genomic alteration in gangliogliomas (GGs) and pleomorphic xanthoastrocytomas (PXAs) with prognostic and therapeutic implications. To investigate the ability of magnetic resonance imaging (MRI) features to predict BRAF V600E status in GGs and PXAs and their prognostic values. A cohort of 44 patients with histologically confirmed GGs and PXAs was reviewed retrospectively. BRAF V600E status was determined by immunohistochemistry (IHC) staining and fluorescence quantitative polymerase chain reaction (PCR). Demographics and MRI characteristics of the two groups were evaluated and compared. Univariate and multivariate Cox regression analyses were performed to identify MRI features that were prognostic for progression-free survival (PFS). T1/FLAIR ratio, enhancing margin, and mean relative apparent diffusion coefficient (rADCmea) value showed significant differences between the BRAF V600E-mutant and BRAF V600E-wild groups (all P < 0.05). Binary logistic regression analysis revealed only rADCmea value was the independent predictive factor for BRAF V600E status (P = 0.027). Univariate Cox regression analysis showed age at diagnosis (P = 0.032), WHO grade (P = 0.020), enhancing margin (P = 0.029), and rADCmea value (P = 0.005) were significant prognostic factors for PFS. In multivariate Cox regression analysis, increasing age (P = 0.040, hazard ratio [HR] = 1.04, 95% confidence interval [CI] = 1.002-1.079) and lower rADCmea values (P = 0.021, HR = 0.036, 95% CI = 0.002-0.602) were associated with poor PFS in GGs and PXAs. Imaging features are potentially predictive of BRAF V600E status in GGs and PXAs. Furthermore, rADCmea value is a valuable prognostic factor for patients with GGs or PXAs.

Constitutional MLH1 Methylation Is a Major Contributor to Mismatch Repair-Deficient, MLH1-Methylated Colorectal Cancer in Patients Aged 55 Years and Younger.

Most mismatch repair-deficient (MMRd) colorectal cancer (CRC) cases arise sporadically, associated with somatic MLH1 methylation, whereas approximately 20% have germline mismatch repair pathogenic variants causing Lynch syndrome (LS). Universal screening of incident CRC uses presence of MLH1 methylation in MMRd tumors to exclude sporadic cases from germline testing for LS. However, this overlooks rare cases with constitutional MLH1 methylation (epimutation), a poorly recognized mechanism for LS. We aimed to assess the frequency and age distribution of constitutional MLH1 methylation among incident CRC cases with MMRd, MLH1-methylated tumors. In retrospective population-based studies, we selected all CRC cases with MMRd, MLH1-methylated tumors, regardless of age, prior cancer, family history, or BRAF V600E status, from the Columbus-area HNPCC study (Columbus) and Ohio Colorectal Cancer Prevention Initiative (OCCPI) cohorts. Blood DNA was tested for constitutional MLH1 methylation by pyrosequencing and real-time methylation-specific PCR, then confirmed with bisulfite-sequencing. Results were achieved for 95 of 98 Columbus cases and all 281 OCCPI cases. Constitutional MLH1 methylation was identified in 4 of 95 (4%) Columbus cases, ages 34, 38, 52, and 74 years, and 4 of 281 (1.4%) OCCPI cases, ages 20, 34, 50, and 55 years, with 3 showing low-level mosaic methylation. Mosaicism in blood and normal colon, plus tumor loss of heterozygosity of the unmethylated allele, demonstrated causality in 1 case with sample availability. Age stratification showed high rates of constitutional MLH1 methylation among younger patients. In the Columbus and OCCPI cohorts, respectively, these rates were 67% (2 of 3) and 25% (2 of 8) of patients aged <50 years but with half of the cases missed, and 75% (3 of 4) and 23.5% (4 of 17) of patients aged ≤55 years with most cases detected. Although rare overall, a significant proportion of younger patients with MLH1-methylated CRC had underlying constitutional MLH1 methylation. Routine testing for this high-risk mechanism is warranted in patients aged ≤55 years for a timely and accurate molecular diagnosis that will significantly alter their clinical management while minimizing additional testing.

Circulating tumor DNA dynamics as an early predictor of recurrence in patients with radically resected colorectal cancer: Updated results from GALAXY study in the CIRCULATE-Japan.

3521 Background: Postoperative circulating tumor DNA (ctDNA)-based molecular residual disease (MRD) is reported to be associated with a high risk of recurrence. Here, we present an updated analysis and the lead time interval (LTI) of ctDNA positivity to radiographic recurrence in patients (pts) with radically resected colorectal cancer (CRC), stage II-IV in the observational GALAXY study. Methods: Serial ctDNA was analyzed using personalized tumor-informed assay (Signatera bespoke multiplex-PCR NGS assay) at 1 (4-week MRD time point), 3, 6, 9, 12, 18, and 24 months after surgery until recurrence, and CT scans were conducted every 6 months. The primary endpoint was disease-free survival (DFS), defined as the time between the date of surgery and date of diagnosis with relapse or death due to any cause. The LTI was defined from the first ctDNA positive date at post-surgery to radiographic recurrence. Results: Among 3,615 CRC pts who were enrolled between May 2020 and April 2022 in GALAXY study, 2,083 pts that met the inclusion criteria were analyzed in this report. The median follow-up period was 16.3 months. Of 2,083 pts analyzed, 286 (14%) were ctDNA-positive at 4-weeks MRD time point and 1,797 (86%) were ctDNA-negative. Pts with ctDNA-positivity at 4-weeks MRD timepoint demonstrated an inferior DFS and were 12 times more likely to recur, compared to ctDNA-negative pts (HR:12, 95CI: 9.1-15%; p &lt; 0.0001). We further combined ctDNA status with BRAF V600E status at 4-week MRD time point and observed that pts with ctDNA-positivity and BRAF V600E mutation showed significantly shorter DFS compared to ctDNA-positive pts with BRAF wild-type (p &lt; 0.001). Whereas, in pts with ctDNA-negativity no significant difference in DFS was observed (p = 0.306). On performing ctDNA dynamics analysis between 4-weeks to 12 weeks, compared to pts who remained ctDNA-negative (N = 1529), a significantly shorter DFS was observed for pts who converted from ctDNA-negative to positive (N = 112, HR: 14.5, 95%CI: 8.8-23.8%, p &lt; 0.0001) or who remained positive (N = 124, HR: 25.4, 95%CI: 18.3-35.3; p &lt; 0.0001). Radiographic recurrence was observed in 186 pts (46%). Of these, 121 pts (65%) had CT imaging performed every 6 months, as per the protocol. The median LTI was 142 days (IQR, 43-189 days). Conclusions: Our study builds on the existing evidence from the recently published, prospective GALAXY study. ctDNA status at MRD time point post-surgery is prognostic of patient outcomes and is the most significant risk factor regardless of BRAF V600E status. ctDNA positivity predicted radiologic recurrence several months ahead of clinical recurrence. Pts with positive postoperative ctDNA should be examined carefully due to a high risk of recurrence. ctDNA-guided adjuvant strategy will further be established by ongoing randomized VEGA and ALTAIR studies in the CIRCULATE-Japan. Clinical trial information: UMIN000039205 .

Budding uninhibited by benzimidazoles 1 might be a poor prognosis biomarker promoting the progression of papillary thyroid cancer.

Papillary thyroid carcinoma (PTC) is one of the most widespread malignant tumors of the endocrine system, with a high incidence. Budding uninhibited by benzimidazoles 1 (BUB1), one of the spindle assembly checkpoint (SAC) genes, is a multitask protein kinase required for eukaryotic chromosome segregation. Although BUB1 has been explored in several types of cancer, its biological role and molecular mechanisms in PTC remain unclear. In this study, we performed an examination of four public datasets along with local PTC cohorts and discovered that BUB1 was elevated in PTC compared to non-cancer tissues. High BUB1 expression was linked with the status of BRAFV600E , RAS, and TERT after statistical analysis. Clinically, BUB1 is associated with a variety of clinicopathological features in PTC patients. Interestingly, analysis of the TCGA database showed that BUB1 was closely associated with poor prognosis of PTC and significantly correlated with PFS. As determined by regression analysis, BUB1, and T stage were independent predictors of PTC and were related to BRAFV600E and lymph node metastatic status. By RT-qPCR, BUB1 was considerably overexpressed in PTC cell lines in comparison with normal thyroid epithelial cells. We confirmed that the knockdown of BUB1 in BCPAP and TPC1 cell lines significantly inhibited cell proliferation, cloning, and migration in vitro experiments. These results imply that BUB1 may be a significant oncogenic gene that is directly associated with the prognosis of PTC and may represent a future target for therapeutic intervention.

Clinicogenomic associations in childhood Langerhans cell histiocytosis: an international cohort study.

Langerhans cell histiocytosis (LCH) is a rare neoplastic disorder caused by somatic genetic alterations in hematopoietic precursor cells differentiating into CD1a+/CD207+ histiocytes. LCH clinical manifestation is highly heterogeneous. BRAF and MAP2K1 mutations account for ∼80% of genetic driver alterations in neoplastic LCH cells. However, their clinical associations remain incompletely understood. Here, we present an international clinicogenomic study of childhood LCH, investigating 377 patients genotyped for at least BRAFV600E. MAPK pathway gene alterations were detected in 300 (79.6%) patients, including 191 (50.7%) with BRAFV600E, 54 with MAP2K1 mutations, 39 with BRAF exon 12 mutations, 13 with rare BRAF alterations, and 3 with ARAF or KRAS mutations. Our results confirm that BRAFV600E associates with lower age at diagnosis and higher prevalence of multisystem LCH, high-risk disease, and skin involvement. Furthermore, BRAFV600E appeared to correlate with a higher prevalence of central nervous system (CNS)-risk bone lesions. In contrast, MAP2K1 mutations associated with a higher prevalence of single-system (SS)-bone LCH, and BRAF exon 12 deletions seemed to correlate with more lung involvement. Although BRAFV600E correlated with reduced event-free survival in the overall cohort, neither BRAF nor MAP2K1 mutations associated with event-free survival when patients were stratified by disease extent. Thus, the correlation of BRAFV600E with inferior clinical outcome is (primarily) driven by its association with disease extents known for high rates of progression or relapse, including multisystem LCH. These findings advance our understanding of factors underlying the remarkable clinical heterogeneity of LCH but also question the independent prognostic value of lesional BRAFV600E status.

Relation between mismatch repair status, chemoresponse, survival and anatomic location in gastroesophageal adenocarcinoma.

It has recently been reported that mismatch repair (MMR) status and microsatellite instability (MSI) status in gastroesophageal carcinomas predict surgical, chemotherapeutic and immunotherapeutic outcomes; however, there is extensive variability in the reported incidence and clinical implications of MMR/MSI status in gastroesophaegal adenocarcinomas. We characterized a Canadian surgical patient cohort with respect to MMR status, clinicopathologic correlates and anatomic tumour location. We investigated MMR and BRAF V600E status of gastroesophaegal adenocarcinomas in patients who underwent gastrectomy or esophagectomy with extended (D2) lymphadenectomy at a single centre between 2011 and 2019. We correlated patterns of MMR expression in the overall cohort and in anatomic location-defined subgroups with treatment response and overall survival using multivariate analysis. In all, 226 cases of gastroesophaegal adenocarcinoma (63 esophageal, 98 gastroesophageal junctional and 65 gastric) were included. The MMR-deficient (dMMR) immunophenotype was found in 28 tumours (12.3%) (15 junctional [15.3%], 13 gastric [20.0%] and none of the esophageal). The majority (25 [89%]) of dMMR cases showed MLH1/PMS2 loss without concurrent BRAF V600E mutation. Two MSH2/ MSH6-deficient gastric tumours and 1 MSH6-deficient junctional tumour were detected. The pathologic response to preoperative chemotherapy was comparable in the dMMR and MMR-proficient (pMMR) cohorts. However, dMMR status was associated with significantly longer median overall survival than pMMR status (5.8 yr v. 2.4 yr, hazard ratio [HR] 1.91, 95% confidence interval [CI] 1.06-3.46), particularly in junctional tumours (4.6 yr v. 1.9 yr, HR 2.97, 95% CI 1.27-6.94). Our study shows that MMR status has at least prognostic value, which supports the need for biomarker testing in gastroesophageal adenocarcinomas, including junctional adenocarcinomas. This highlights the clinical significance of determining the MMR status in all adenocarcinomas of the upper gastrointestinal tract. Response to induction chemotherapy, however, was not influenced by MMR status.

NRG-GI004/SWOG-S1610: Colorectal Cancer Metastatic dMMR Immuno-Therapy (COMMIT) study—A randomized phase III study of atezolizumab (atezo) monotherapy versus mFOLFOX6/bevacizumab/atezo in the first-line treatment of patients (pts) with deficient DNA mismatch repair (dMMR) or microsatellite instability high (MSI-H) metastatic colorectal cancer (mCRC).

TPS258 Background: Despite the superiority in progression-free survival (PFS) of inhibition of programmed cell death-1 (PD-1) pathway in dMMR/MSI-H as compared to chemotherapy with either anti-vascular endothelial growth factor receptor (VEGFr) or anti-epithelial growth factor receptor (EGFr) antibodies in mCRC, more pts had progressive disease as the best response in the anti-PD1 monotherapy arm (29.4% v 12.3%) with mean PFS of 13.7 mos, with ~45% of pts in the immunotherapy arm progressed at 12 mos (KEYNOTE 177). We hypothesize that dMMR/MSI-H mCRC pts may be more effectively treated with the combination of PD-1 pathway blockade and mFOLFOX6/bevacizumab (bev) rather than with anti-PD-1 therapy (atezo) alone. Preclinical work demonstrated synergistic effects between anti-PD-1/anti-VEGF and between oxaliplatin/anti-PD-1 in murine CRC models and phase II data, which showed activity of anti-PD-1/anti-VEGF in chemotherapy refractory colon cancer. A recent randomized trial subgroup analysis of 8 pts with dMMR metastatic colon cancer treated with FOLFOXIRI+bev+atezo, with the first patient having progression ~16 mos (AtezoTRIBE). Additionally, in other solid tumor malignancies, anti-PD1 plus anti-VEGFr (i.e., HCC and RCC) as well as anti-PD1 plus chemotherapy (i.e., gastric and esophageal cancers) combinations are standard first-line treatments. Methods: The redesigned COMMIT study was reactivated on 1/29/2021 as a two-arm prospective phase III open-label trial randomizing (1:1) mCRC dMMR/MSI-H to atezo monotherapy v mFOLFOX6/bev+atezo combination. Assuming our control arm, atezo monotherapy (48% PFS at 24 mos as assessed by site investigator), we have 80% power to detect a hazard ratio of 0.6 (equivalent to 64.4% PFS at 24 mos) with alpha 0.025 one-sided. Stratification factors include BRAFV600E status, metastatic site, and prior adjuvant CRC therapy. Secondary endpoints include OS, objective response rate, safety profile, disease control rate, and duration of response. Health-related quality of life is an exploratory objective. Archived tumor tissue and blood samples will be collected for correlative studies. Key inclusion criteria are: mCRC without prior chemotherapy for advanced disease; dMMR tumor determined by local CLIA-certified IHC assay (MLH1/MSH2/MSH6/PMS2) or MSI-H by local CLIA-certified PCR or NGS panel; and measurable disease per RECIST. Enrollment actively continues to the target accrual of 211 patients randomized between the two immunotherapy arms. Clinical trial: NCT02997228. Support: U10CA180868, -180822, -180888, UG1CA189867, U24CA196067; Genentech, Inc. Clinical trial information: NCT05080673 .