Poorly differentiated, resectable pancreatic ductal
adenocarcinoma is associated with early recurrence and may benefit from
neoadjuvant treatment. The aim of this study was to evaluate clinicopathologic characteristics and survival of patients with resectable pancreatic ductal
adenocarcinoma according to histologic grading.
METHODS: Well-differentiated (G1), moderately differentiated (G2), and poorly differentiated (G3) pancreatic ductal
adenocarcinomas were found in 23 (4.5%), 310 (62%), and 169 (33.5%) patients. Adjuvant
therapy, N status, grading, and R status were independent predictors of disease-specific survival for the entire cohort, with 1- and 5-year disease-specific survival rates of 81% and 21%, respectively. Only the presence of symptoms was a significant clinical predictor of G3 status (P = .035). G3
neoplasms were characterized by a greater rate of
lymph node metastases, microvascular/perineural invasion, and R2 resections. Median disease-specific survival was 77, 26, and 20 months for G1, G2, and G3
neoplasms (P < .0001). Median disease-free survival was 63, 14, and 9 months for G1, G2, and G3 pancreatic ductal
adenocarcinoma (P < .0001). Adjuvant
therapy improved disease-specific survival in G2 (P < .04) and G3 (P < .0001) pancreatic ductal
adenocarcinoma, with a greater survival benefit for G3
neoplasms (hazard ratio: 1.334 vs 2.116).
CONCLUSION: G3 pancreatic ductal
adenocarcinoma is associated with a lesser rate of disease-free survival after resection and with the presence of other poor prognostic factors. The benefit of adjuvant
therapy is greater in G3 than in G1 and G2
neoplasms. On the basis of these findings, patients with resectable G3 PDAC can be considered as possible targets for
neoadjuvant treatment.