Metastatic pattern is a prognostic factor in BRAFV600E mutant colorectal cancer

Abstract

Background

Despite recent advancements in the treatment of metastatic BRAF^V600E colorectal cancer (CRC), prognosis remains poor. However, a some patients with BRAF^V600E disease have superior outcomes compared to the overall cohort and the prognostic factors associated with this improved survival are not well understood.

Methods

We conducted a single center retrospective review of patients with metastatic CRC and available next generation sequencing data. Patients with confirmed BRAF^V600E disease were selected for the final analysis. We collected baseline demographic characteristics, concurrent mutations, and metastatic pattern. The primary endpoint was overall survival (OS). Univariate and multivariable logistic regression was used to examine the association between baseline concurrent somatic mutations and sites of metastatic disease with survival.

Results

Of 466 patients with metastatic CRC, 50 harbored BRAF^V600E disease and 42 were included in the final analysis. The median OS in this cohort was 18.7 months (95% CI: 5.55–31.8). There was no association between baseline concurrent somatic mutations and OS. On univariate analysis, patients with lymph node only disease at the time of metastatic disease were more likely to have longer OS (hazard ratio [HR] = 0.30, 95% CI: 0.09–0.98, p = 0.047) and patients with peritoneal disease were more likely to have shorter OS (HR = 2.78, 95% CI: 1.12–6.88, p = 0.03). However, these associations did not retain statistical significance on multivariable analysis.

Conclusions

The pattern of metastatic disease in BRAF^V600E CRC may be a prognostic factor and future studies are needed to better understand the underlying mechanisms and potentially change clinical practice for a select patient population.

MicroAbstract

Select patients with metastatic BRAF^V600E colorectal cancer may have better than expected survival but are not well characterized. We conducted a retrospective review of 42 patients with metastatic BRAF^V600E colorectal cancer and showed that lymph node only disease at the time of metastatic disease was associated with superior survival.