The role of adjuvant platinum-based chemotherapy in esophagogastric cancer patients who received neoadjuvant chemotherapy prior to definitive surgery.

ABSTRACT

BACKGROUND AND OBJECTIVES: For patients with operable esophagogastric cancer, peri-operative chemotherapy confers a significant overall survival benefit compared to surgery alone, however only 30-40% of patients demonstrate histopathological response. It is unclear whether those with no neoadjuvant chemotherapy response should go onto receive adjuvant chemotherapy, as no further benefit may be conferred. METHODS: Esophagogastric cancers were prospectively captured with associated histopathological tumor regression grades following neoadjuvant chemotherapy. This cohort was then interrogated for clinico-pathological and survival outcomes. RESULTS: Following neoadjuvant chemotherapy and surgery, patients with chemotherapy responsive cancers, who were administered adjuvant chemotherapy gained a significant overall survival benefit. Multivariate Cox analysis, demonstrated a final adjusted hazard ratio for adjuvant therapy of 0.509; (95%CI 0.28-0.93); P = 0.028. In contrast, patients with non-responsive tumors, who underwent adjuvant chemotherapy, did not show any survival benefit. Chemotherapy toxicity was prevalent and contributed to only half of patients receiving adjuvant chemotherapy. CONCLUSIONS: These results suggest the benefit of the adjuvant portion of chemotherapy is limited to those who demonstrate a histopathological response to neoadjuvant chemotherapy. The administration of the adjuvant portion of chemotherapy to patients without a response to neoadjuvant chemotherapy may not provide any survival benefit, while potentially causing increased morbidity.