Oncological outcome of surgical resection for anaplastic carcinoma of the pancreas.

Anaplastic carcinoma of the pancreas (ACP) is a rare disease with rapid growth. Therefore, the significance of surgery for ACP remains unknown. The present study aimed to elucidate the oncological outcome following surgical resection for ACP and investigated pathological features associated with prognosis. In the present study, 12 patients who underwent surgical resection for ACP at Chiba University Hospital (Chiba, Japan) were retrospectively analyzed. Among the 12 patients, 7 had anaplastic undifferentiated carcinoma, 1 had sarcomatoid undifferentiated carcinoma, 2 had carcinosarcoma and 2 had undifferentiated carcinoma with osteoclast-like giant cells (OCGC). A total of 7 cases exhibited early recurrence within 6 months postoperatively, and the median overall survival (OS) time of the patients with curative resection was 15.0 months, which was shorter than that of patients with pancreatic ductal adenocarcinoma. The median OS time of patients with pT3 was significantly shorter than that of those with pT1 or pT2 (2.2 vs. 24.5 months; P<0.01). pT3 tumors frequently exhibited a high Ki-67 proliferative index with tumor necrosis and intratumoral hemorrhage. These cases exhibited high serum inflammatory marker levels, including white blood cells, C-reactive protein and neutrophil-to-lymphocyte ratio. On the other hand, 4 patients survived for ≥2 years without recurrence after surgery. These patients included 2 cases with undifferentiated carcinoma with OCGC and 2 pT1 cases with undifferentiated carcinoma who did not exhibit tumor necrosis or intratumoral hemorrhage. The present study demonstrated that a number of ACP cases exhibited early recurrence with poor survival, whereas limited cases experienced long-term survival. The tumor subtype and pathological features, such as tumor diameter, tumor necrosis and intratumoral hemorrhage, may be associated with the postoperative prognosis of patients with ACP.