This retrospective study provides valuable insights into the impact of HER2 status on treatment outcomes in advanced gastric cancer patients receiving first-line chemotherapy plus trastuzumab. The research focused on comparing two groups of HER2-positive patients: those with IHC 2+/FISH positive status and those with IHC 3+ status. The study's cohort consisted of 144 patients, with 45 (31.3%) identified as HER2 positive. Among the HER2-positive patients, 12 (26.7%) were classified as IHC 2+/FISH positive, while 33 (73.3%) were classified as IHC 3+. The researchers assessed diverse clinical and pathological aspects, encompassing patient characteristics, neoplasm positioning, and histological variants. They also explored therapeutic outcomes and long-term survival data. The study's findings revealed no significant differences in treatment efficacy between the two HER2-positive groups. Objective response rates and disease control rates were comparable, with 50% vs. 75% vs. 51.5% and 75.8%, respectively (p=0.946). Progression-free survival was similar, with a median of 8.5 months in the IHC 2+/FISH positive group and 9.6 months in the IHC 3+ group (p=0.87). Overall survival also showed no statistically significant difference, with median durations of 13.2 months and 16.2 months for the IHC 2+/FISH positive and IHC 3+ groups, respectively (p=0.38). These results suggest that the efficacy of first-line chemotherapy plus trastuzumab in advanced gastric cancer is comparable across different HER2-positive statuses, indicating that this treatment approach may be equally effective for patients with either IHC 2+/FISH positive or IHC 3+ HER2 status. This information is crucial for clinicians in making informed decisions regarding treatment strategies for HER2-positive advanced gastric cancer patients.
AYTAÇ et al. (Tue,) studied this question.