Distribution of Resistant Esophageal Adenocarcinoma in the Resected Specimens of Clinical Stage III Patients after Chemoradiation: Its Clinical Implications.

BACKGROUND: We have limited knowledge of the geographic distribution of resistant esophageal adenocarcinoma (EAC) in resected specimens, but its clinical importance can be enormous.
METHOD: We selected patients with baseline stage III EAC who had had chemoradiation followed by surgery and had residual EAC (resistant cases only). Outcomes were correlated with various endpoints (percentage of resistant EAC and anatomic distribution).
RESULTS: A total of 100 clinical stage III patients were studied; 90% had an R0 resection, and 99% had either moderate or poorly differentiated EAC. Twelve percent had >50% residual cancer, 31% had 11-50% residual cancer, 53% had 1-10% residual cancer, and 3% had positive nodes only. Each compartment was frequently involved: mucosa/submucosa (66%), muscularis propria (76%), and serosa (62%); all compartments were involved in 35% of the cases. Lack of EAC (meaning response) was observed in the mucosa/submucosa (34%), muscularis propria (24%), serosa (38%), and nodes (42%). Although the endoscopic biopsies prior to surgery showed no EAC in 79% of the patients, in the surgical specimens, resistant EAC was frequently occurring in the mucosa/submucosa (66%).
CONCLUSION: Contrary to our hypothesis that resistant EAC would be frequent in the nodes, our data show that its distribution is heterogeneous and unpredictable. Most importantly, the postchemoradiation biopsies are misleading, and a decision to delay/avoid surgery based on negative biopsies can be detrimental for the patients.