Impact of histopathology on the outcome of D1/D2 gastrectomies with R0 resection.

AIMS: The primary objective of this study was to clarify the influence of histotype on the outcome of D1/D2 gastrectomized patients with pathologically proven R0 resection. The secondary objective was to demonstrate overall survival (OS), disease-free survival (DFS), and locoregional recurrence rates following standard curative surgery.

PATIENTS AND METHODS: All patients had either pure signet-ring cell carcinoma (SRCC)/poorly differentiated adenocarcinoma (PDC) or moderately differentiated adenocarcinoma (MDC) of the stomach, preoperative radiologic evidence of locoregional disease, and no history of neoadjuvant therapy. Standards of surgical treatment were essentially based on the guidelines of the Japanese Research Society for the Study of Gastric Cancer.

RESULTS: Between October 2003 and August 2010, seventy-eight patients were enrolled. Twenty-three patients underwent D1 dissection and 55 underwent D2 dissection. The OS and DFS rates were 33.2 ± 5.9 months versus 31.5 ± 4.3 months (p = 0.81) and 28.9 ± 5.6 months vs. 29.3 ± 4.4 months (p = 0.96) in the MDC and SRCC/PDC groups, respectively. Neither the extent of the operation (D1 vs. D2, p = 0.79) nor the histopathologic subtype of the primary tumor (MDC vs. SRCC/PDC, p = 0.91) influenced the OS and DFS. Multivariate logistic regression analysis disclosed pathologic stage (pTNM) as the only significant prognostic determinant of OS (p = 0.007) and DFS (p = 0.0003).

CONCLUSION: Properly performed D1 and D2 dissection in our series resulted in a notable (6.4%) locoregional failure rate. In spite of the satisfactory locoregional control achieved by D1 and D2, there was no improvement in the survival figures of stage IIIA-B and IV gastric cancer patients. The histopathologic subtype of the primary tumor disclosed merely a statistical trend on the outcome measures of gastric cancer after curative surgery.