Background: BRAF mutations portend a poor prognosis in metastatic colorectal cancer (mCRC). Whether these patients may benefit from more aggressive frontline chemotherapy with a triplet regimen such as FOLFOXIRI remains unclear. We used real-world data from a cohort of patients in the United States to assess the BRAF testing rate, determine the prevalence of FOLFOXIRI use, and compare survival outcomes in mCRC, stratified by BRAF mutation status and first-line therapy. Methods: A nationwide electronic health record–derived deidentified database was reviewed for patients diagnosed with mCRC between 2013 and 2018. Those with documented BRAF mutation testing who received standard first-line therapy were included. Kaplan-Meier estimates with corresponding log-rank tests and Cox proportional hazards modeling compared survival outcomes stratified by BRAF status and first-line therapy. Results: Of 4,457 included patients, 3,991 (89.5%) had BRAF wild-type (BRAFwt) and 466 (10.5%) had BRAF-mutated (BRAFmt) mCRC. Median overall survival (OS) was 15.4 months in the BRAFmt group versus 28.1 months in the BRAFwt group (hazard ratio [HR], 0.48; 95% CI, 0.41–0.56; P<.001). Only 3% of patients with BRAF mutations received first-line FOLFOXIRI ± bevacizumab, with a median OS of 13.8 months compared with 15.5 months in those treated with doublet chemotherapy ± bevacizumab (P=.38). In patients with BRAF mutations, propensity-weighted analysis did not detect a significant improvement in OS with FOLFIRI + bevacizumab (HR, 0.90; 95% CI, 0.58–1.39; P=.63) or FOLFOX/CAPEOX + bevacizumab (HR, 0.81; 95% CI, 0.52–1.26; P=.35) versus doublet chemotherapy alone. In 2018, only 56% of patients diagnosed with mCRC had documented BRAF testing at any time. Conclusions: This real-world data analysis confirms the negative prognostic impact of BRAF mutations in mCRC and suggests that FOLFOXIRI has not been widely adopted in the United States. The proportion of patients with documented BRAF testing in this real-world population was low at 56%. We were unable to show any significant difference in OS of patients with BRAFmt mCRC based on the first-line therapy received.
Andrew Trunk, Matthew Braithwaite, Christopher Nevala-Plagemann, Lisa Pappas, Benjamin Haaland, and Ignacio Garrido-Laguna
Christopher Nevala-Plagemann, Siddharth Iyengar, Andrew D. Trunk, Lisa Pappas, Benjamin Haaland, and Ignacio Garrido-Laguna
Background: Post hoc analysis of the CALGB/SWOG 80405 trial suggests that anti-EGFR therapy may be superior to bevacizumab when added to first-line chemotherapy in patients with metastatic colorectal cancer (mCRC) who have left-sided primary tumors. We evaluated trends in use of anti-EGFR agents in patients with left-sided RAS/RAF wild-type (WT) mCRC and compared clinical outcomes among the most commonly used treatment strategies. Methods: A nationwide electronic health record (EHR)–derived deidentified database was reviewed for patients with left-sided RAS/RAF WT mCRC. Treatment trends over time were assessed by fitting a linear model to the percentage of patients receiving anti-EGFR therapy. A propensity score weighted Cox model was used to compare overall survival (OS) stratified by first-line targeted therapy received. Results: A total of 1,607 patients with left-sided RAS/RAF WT mCRC received standard first-line chemotherapy. Of these, 965 (60%) received bevacizumab and 186 (12%) received an anti-EGFR agent. The percentage of patients receiving an anti-EGFR increased from 9% in 2013 to 16% in 2018. Median OS for patients treated with chemotherapy alone was 27.3 months (95% CI, 24.8–32.3), 27.5 months with bevacizumab (95% CI, 25.8–28.9; hazard ratio [HR], 0.88; P=.33), and 42.9 months with an anti-EGFR agent (95% CI, 36.0 to not reached; HR, 0.52; P=.005). Conclusions: This analysis suggests that chemotherapy with bevacizumab remained the most widely used first-line treatment strategy for patients with left-sided RAS/RAF WT mCRC in the United States in 2018. Despite this preference, treatment with an anti-EGFR agent was associated with improved OS.
Christopher Nevala-Plagemann, Shashank Sama, Jian Ying, Jincheng Shen, Benjamin Haaland, Vaia Florou, and Ignacio Garrido-Laguna
Background: Trifluridine/Tipiracil (TAS-102) and regorafenib are FDA-approved in the United States for treatment of refractory metastatic colorectal cancer (mCRC). FDA approvals of these agents were based on modest improvements in overall survival (OS) compared with best supportive care + placebo in the RECOURSE and CORRECT trials, respectively. This study compared real-world clinical outcomes with the use of these agents. Methods: A nationwide deidentified electronic health record–derived database was reviewed for patients diagnosed with mCRC between 2015 and 2020. Patients who received at least 2 lines of standard systemic therapy followed by treatment with either TAS-102 or regorafenib were included for analysis. Kaplan-Meier and propensity score–weighted proportional hazards models were used to compare survival outcomes between groups. Results: The records of 22,078 patients with mCRC were reviewed. Of these, 1,937 patients received at least 2 lines of standard therapy followed by regorafenib and/or TAS-102. Median OS for the TAS-102 alone or prior regorafenib group (n=1,016) was 6.66 months (95% CI, 6.16–7.18 months) compared with 6.30 months (95% CI, 5.80–6.79 months) for regorafenib alone or prior to TAS-102 (n=921; P=.36). A propensity score–weighted analysis controlling for potential confounders did not demonstrate a significant difference in survival between groups (hazard ratio, 0.99; 95% CI, 0.90–1.09; P=.82). A subgroup analysis did not identify any significant differences in outcomes regarding age, performance status, tumor sidedness, microsatellite instability status, or RAS/RAF status. Conclusions: This analysis of real-world data found that OS was similar for patients with mCRC who were treated with TAS-102 compared with regorafenib. Median OS with both agents in a real-world setting was similar to that shown in the clinical trials that led to their approvals. A prospective trial comparing TAS-102 and regorafenib would unlikely change current management of patients with refractory mCRC.
Vaia Florou, Christopher Nevala-Plagemann, Jonathan Whisenant, Patricia Maeda, Glynn W. Gilcrease, and Ignacio Garrido-Laguna
NTRK gene fusions are found in <1% of all cancers but are uniformly present in mammary analog secretory carcinomas (MASC) of the salivary glands. Two selective histology-agnostic tropomyosin receptor kinase (TRK) inhibitors are currently approved for malignancies with these oncogenic fusions. Resistance to TRK inhibition has been recognized, and the mediating mechanisms are presently being studied. This report describes a patient diagnosed with an MASC of the parotid gland who after undergoing multiple lines of treatment was found to have an ETV6-NTRK3 fusion and initiated TRK-targeted therapy using entrectinib. Upon disease progression, we performed tumor genetic sequencing that showed a secondary resistance mutation. The patient subsequently responded to selitrectinib, a next-generation TRK inhibitor.