Core homologous recombination mutations improve survival in nonpancreatic GI cancers

Both core and noncore homologous recombination mutations (HRMs) respond to platinum chemotherapy in metastatic nonpancreatic gastrointestinal (GI) cancers, which suggests benefit in the two groups, reports a study.

“Core HRM patients had significantly increased median overall survival (OS) and median progression-free survival (PFS) compared with those with noncore HRM, suggesting potential prognostic and predictive significance,” the authors said.

This study, which sought to assess the prognostic and predictive role of core (BRCA1, BRCA2, PALB2) and noncore HRM in nonpancreatic GI cancers receiving platinum therapy, was conducted at Moffitt Cancer Center in Florida, US.

All patients received either a core or noncore HRM, determined by next-generation sequencing. The authors also determined response, median PFS, and median OS and compared these between core and noncore HRM patients.

Sixty-nine patients (63.8 percent male, 87.0 percent Caucasian, 47.9 percent with colorectal cancer) with one or more HRM were included, of whom 21 (30.4 percent) had a core HRM and 48 (69.6 percent) had a noncore HRM.

Sixty-four patients were evaluable, among whom no significant difference was observed in objective response: 20.0 percent with core HRM vs 22.7 percent with noncore HRM responded to platinum therapy (p=0.53).

Median PFS was 10.4 months for core HRM and 7.1 months for noncore HRM (p=0.039), while median OS was 68.9 months and 24.3 months, respectively (p=0.026).

“Larger prospective studies are needed to confirm our findings,” the authors said.