Project description:PurposeTo evaluate dabrafenib, a selective BRAF inhibitor, combined with trametinib, a selective MEK inhibitor, in patients with BRAF V600-mutant metastatic colorectal cancer (mCRC).Patients and methodsA total of 43 patients with BRAF V600-mutant mCRC were treated with dabrafenib (150 mg twice daily) plus trametinib (2 mg daily), 17 of whom were enrolled onto a pharmacodynamic cohort undergoing mandatory biopsies before and during treatment. Archival tissues were analyzed for microsatellite instability, PTEN status, and 487-gene sequencing. Patient-derived xenografts were established from core biopsy samples.ResultsOf 43 patients, five (12%) achieved a partial response or better, including one (2%) complete response, with duration of response > 36 months; 24 patients (56%) achieved stable disease as best confirmed response. Ten patients (23%) remained in the study > 6 months. All nine evaluable during-treatment biopsies had reduced levels of phosphorylated ERK relative to pretreatment biopsies (average decrease ± standard deviation, 47% ± 24%). Mutational analysis revealed that the patient achieving a complete response and two of three evaluable patients achieving a partial response had PIK3CA mutations. Neither PTEN loss nor microsatellite instability correlated with efficacy. Responses to dabrafenib plus trametinib were comparable in patient-derived xenograft-bearing mice and the biopsied lesions from each corresponding patient.ConclusionThe combination of dabrafenib plus trametinib has activity in a subset of patients with BRAF V600-mutant mCRC. Mitogen-activated protein kinase signaling was inhibited in all patients evaluated, but to a lesser degree than observed in BRAF-mutant melanoma with dabrafenib alone. PIK3CA mutations were identified in responding patients and thus do not preclude response to this regimen. Additional studies targeting the mitogen-activated protein kinase pathway in this disease are warranted.
Project description:Colorectal cancer (CRC) is the third leading cause of cancer-related deaths in the United States. Despite advancements in detection and therapeutic options, patients with metastatic CRC continue to face poor survival rates. The heterogeneity of oncogenic alterations, including BRAF mutations, poses a substantial challenge in identifying optimal treatment approaches. Notably, BRAF non-V600 mutations, encompassing class II and class III mutations, exhibit the distinct patterns of the signaling pathways and responses to targeted therapies compared to BRAF V600 mutations (class I). Nevertheless, the current classification system may underestimate the complexity and heterogeneity of BRAF-mutant CRC. Ongoing clinical trials are actively investigating targeted therapies for BRAF non-V600 mutations, but they are being confronted with patient recruitment obstacles due to the genetic diversity of these alterations. Continued research is needed to refine mutation subtyping, identify effective treatment strategies, and improve outcomes for patients with BRAF non-V600-mutant CRC. Enhancing our understanding and management of this specific subgroup of CRC is crucial for developing personalized treatment approaches and advancing patient care. This manuscript provides a comprehensive overview of the recent advances in and perspectives on BRAF non-V600 alterations in colorectal cancer, including relevant ongoing clinical trials.
Project description:PurposeWhile mutations in BRAF in metastatic colorectal cancer (mCRC) most commonly occur at the V600 amino acid, with the advent of next-generation sequencing, non-V600 BRAF mutations are increasingly identified in clinical practice. It is unclear whether these mutants, like BRAF V600E, confer resistance to anti-EGFR therapy.Experimental designWe conducted a multicenter pooled analysis of consecutive patients with non-V600 BRAF-mutated mCRCs identified between 2010 and 2017. Non-V600 BRAF mutations were divided into functional classes based on signaling mechanism and kinase activity: activating and RAS-independent (class 2) or kinase-impaired and RAS-dependent (class 3).ResultsForty patients with oncogenic non-V600 BRAF-mutant mCRC received anti-EGFR antibody treatment [n = 12 (30%) class 2 and n = 28 (70%) class 3]. No significant differences in clinical characteristics were observed by mutation class. In contrast, while only 1 of 12 patients with class 2 BRAF mCRC responded, 14 of 28 patients with class 3 BRAF responded to anti-EGFR therapy (response rate, 8% and 50%, respectively, P = 0.02). Specifically, in first- or second-line, 1 of 6 (17%) patients with class 2 and 7 of 9 (78%) patients with class 3 BRAF mutants responded (P = 0.04). In third- or later-line, none of 6 patients with class 2 and 7 of 19 (37%) patients with class 3 BRAF mutants responded (P = 0.14).ConclusionsResponse to EGFR antibody treatment in mCRCs with class 2 BRAF mutants is rare, while a large portion of CRCs with class 3 BRAF mutants respond. Patients with colorectal cancer with class 3 BRAF mutations should be considered for anti-EGFR antibody treatment.See related commentary by Fontana and Valeri, p. 6896.
Project description:The personalization of cancer care is rooted in the premise that there are subsets of patients with tumors harboring clinically relevant targets for patient-specific treatments. Colorectal cancer (CRC) is a disease that has historically been notable for its dearth of biomarkers that are predictive of response to targeted therapies. In recent years, BRAFV600E-mutated CRC has emerged as a distinct biologic entity, typically refractory to standard chemotherapy regimens approved for the treatment of metastatic CRC and associated with a dismal prognosis. Multiple clinical trials sought to replicate the successes of targeted therapies seen in BRAFV600E-mutated melanoma without success; metastatic BRAFV600E-mutated CRC is clearly a distinct biologic entity. We review a number of recent studies demonstrating the evidence of modest responses to combinations of BRAF, EGFR, and/or MEK inhibition in patients with metastatic BRAFV600E-mutated CRC; however, despite advances, overall survival remains far inferior for these patients compared to their BRAF-wild-type counterparts. Development of combination therapies to impede signaling through the MAPK pathway through alternate targets remains an area of active investigation. Reflecting the rapid evolution of efforts for this small subset of CRC patients, the first-ever Phase III study is now underway evaluating the combination of BRAF, EGFR, and MEK inhibition. Immunotherapies are also an area of active research, particularly for the subset of patients with tumors that are also microsatellite instability (MSI) high. Here, we summarize the current landscape and emerging data on the molecular, clinical, and therapeutic aspects of BRAF-mutant CRC.
Project description:The treatment of metastatic colorectal cancer (mCRC) harboring BRAF V600 mutations is challenging. These tumors are often refractory to standard treatment. Therefore, the patients may exhibit rapid clinical deterioration, depriving them of the chance to receive salvage therapy. In newly diagnosed patients with good performance status, the administration of an intensive chemotherapy regimen like FOLFOXIRI (5-fluorouracil, leucovorin, oxaliplatin, and irinotecan) along with the antiangiogenic agent bevacizumab can modify this aggressive behavior of the disease and improve patient clinical outcomes. The recently published results of the BEACON (Binimetinib, Encorafenib, and Cetuximab Combined to Treat BRAF-Mutant Colorectal Cancer) study demonstrated that a combination therapy consisting of BRAF, epidermal growth factor receptor, and mitogen-activated protein kinase kinase inhibitors could be a useful second-or third-line alternative. This review summarizes the current treatment strategies for BRAF-mutant mCRC.
Project description:Purpose We report the efficacy and safety of dabrafenib (BRAF inhibitor) and trametinib (MEK inhibitor) combination therapy in BRAF V600E-mutated anaplastic thyroid cancer, a rare, aggressive, and highly lethal malignancy with poor patient outcomes and no systemic therapies with clinical benefit. Methods In this phase II, open-label trial, patients with predefined BRAF V600E-mutated malignancies received dabrafenib 150 mg twice daily and trametinib 2 mg once daily until unacceptable toxicity, disease progression, or death. The primary end point was investigator-assessed overall response rate. Secondary end points included duration of response, progression-free survival, overall survival, and safety. Results Sixteen patients with BRAF V600E-mutated anaplastic thyroid cancer were evaluable (median follow-up, 47 weeks; range, 4 to 120 weeks). All patients had received prior radiation treatment and/or surgery, and six had received prior systemic therapy. The confirmed overall response rate was 69% (11 of 16; 95% CI, 41% to 89%), with seven ongoing responses. Median duration of response, progression-free survival, and overall survival were not reached as a result of a lack of events, with 12-month estimates of 90%, 79%, and 80%, respectively. The safety population was composed of 100 patients who were enrolled with seven rare tumor histologies. Common adverse events were fatigue (38%), pyrexia (37%), and nausea (35%). No new safety signals were detected. Conclusion Dabrafenib plus trametinib is the first regimen demonstrated to have robust clinical activity in BRAF V600E-mutated anaplastic thyroid cancer and was well tolerated. These findings represent a meaningful therapeutic advance for this orphan disease.
Project description:BRAF plus MEK inhibitor combinations are currently FDA-approved for melanoma, non-small cell lung cancer, and anaplastic thyroid cancer. The lack of clinical benefit with BRAF inhibition in BRAF V600-mutated colorectal cancer has prevented its tissue-agnostic drug development. We reviewed the AACR GENIE database for the prevalence of BRAF V600 mutations across tumor types. We reviewed the literature for case reports of clinical responses, outcomes in patients with BRAF V600 mutation-positive nonmelanoma malignancies who received BRAF inhibitor therapy, and data from published adult and pediatric trials. BRAF V600 mutations are prevalent across multiple nonmelanoma malignancies (>40 different tumor types), lead to oncogene addiction, and are clinically actionable in a broad range of adult and pediatric nonmelanoma rare malignancies. Continued tissue-agnostic drug development is warranted beyond the current BRAF plus MEK approved cancers.
Project description:BackgroundApproximately 50% of melanomas harbor activating (V600) mutations in the serine-threonine protein kinase B-RAF (BRAF). The oral BRAF inhibitor vemurafenib (PLX4032) frequently produced tumor regressions in patients with BRAF V600-mutant metastatic melanoma in a phase 1 trial and improved overall survival in a phase 3 trial.MethodsWe designed a multicenter phase 2 trial of vemurafenib in patients with previously treated BRAF V600-mutant metastatic melanoma to investigate the efficacy of vemurafenib with respect to overall response rate (percentage of treated patients with a tumor response), duration of response, and overall survival. The primary end point was the overall response rate as ascertained by the independent review committee; overall survival was a secondary end point.ResultsA total of 132 patients had a median follow-up of 12.9 months (range, 0.6 to 20.1). The confirmed overall response rate was 53% (95% confidence interval [CI], 44 to 62; 6% with a complete response and 47% with a partial response), the median duration of response was 6.7 months (95% CI, 5.6 to 8.6), and the median progression-free survival was 6.8 months (95% CI, 5.6 to 8.1). Primary progression was observed in only 14% of patients. Some patients had a response after receiving vemurafenib for more than 6 months. The median overall survival was 15.9 months (95% CI, 11.6 to 18.3). The most common adverse events were grade 1 or 2 arthralgia, rash, photosensitivity, fatigue, and alopecia. Cutaneous squamous-cell carcinomas (the majority, keratoacanthoma type) were diagnosed in 26% of patients.ConclusionsVemurafenib induces clinical responses in more than half of patients with previously treated BRAF V600-mutant metastatic melanoma. In this study with a long follow-up, the median overall survival was approximately 16 months. (Funded by Hoffmann-La Roche; ClinicalTrials.gov number, NCT00949702.).
Project description:Since the inception of this journal in 1948, the understanding of etiologic factors that contribute to and the treatment of head and neck cancer has evolved dramatically. Advances in surgery, radiation therapy, and chemotherapy have improved locoregional control, survival, and quality of life. The outcomes of these treatment modalities have shifted the focus of curative efforts from radical ablation to preservation and restoration of function. This evolution has been documented in the pages of Cancer for the past 6 decades. This review focuses on the evolution of treatment approaches for head and neck cancer and future directions while recognizing the historic contributions recorded within this journal.
Project description:BackgroundBRAF mutation occurs in 5%-10% of metastatic colorectal cancers (mCRCs). Patients with BRAF mutant mCRC exhibit a specific metastatic pattern and poor prognosis. Survival outcomes are heterogeneous in cases of mCRC with a BRAF mutation. The optimal first-line therapy is still controversial.MethodsWe retrospectively reviewed the medical records of patients with mCRC between June 2010 and December 2021. Clinicopathologic characteristics, treatment and BRAF mutation testing results were collected. Patients with a BRAF mutation were included. Kaplan-Meier methods and log-rank tests were used to analyze and compare survival. Cox proportional hazards regression was used to establish the predictive nomogram model.ResultsOf the 4475 mCRC, 261 have a BRAF mutation, including 240 V600E and 21 non-V600E mutants. The median overall survival (OS) was 18.2 months in the BRAF V600E mutant group versus 38.0 months in the non-V600E mutant group (p = 0.022). ECOG score, tumor differentiation, liver metastasis, bone metastasis and primary tumor resection were independent prognostic factors for the OS of BRAF V600E mutant mCRC. A nomogram model was established using these factors. The median OS was 39.3 m, 18.2 m and 10.7 m for the low-risk, intermediate-risk and high-risk groups defined by this model, respectively (p < 0.0001). Patients who received first-line triplet chemotherapy ± bevacizumab had comparable progression free survival (PFS) and OS compared with those treated with doublets ± bevacizumab.ConclusionBRAF V600E mutant mCRCs exhibit unfavorable and heterogeneous prognosis. The first-line intensive chemotherapy did not confer a marked impact on the PFS and OS.