Intraductal papillary-mucinous tumor of the pancreas concomitant with ductal carcinoma of the pancreas

Background: Despite the recent progress of diagnostic and therapeutic modalities, the clinical course of patients with ductal carcinoma (DC) of the pancreas remains dismal. Intraductal papillary-mucinous tumor of the pancreas (IPMT) is sometimes accompanied by malignant diseases of the other organs and pancreatic adenocarcinoma. Thus, IPMT may be a potential diagnostic clue to DC of the pancreas at early phase.

Methods: Clinicopathologic findings of 7 Japanese patients with IPMT of the pancreas concomitant with independent DC were examined and compared with those of 69 patients with IPMT alone and of 70 with DC alone.

Results: The seven patients corresponded to 9.2% of 76 patients with IPMT and 9.1% of 77 patients with DC. The seven male patients ranged from 55 to 75 years with a mean of 64.3. DC was synchronous with IPMT in five patients, metachronous to IPMT (4 years after IPMT) in one, and synchronous with IPMT and metachronous to IPMT and DC (7 years after IPMT) in the other. In 4 patients, the presence of IPMT led to the diagnosis of DC. All the 7 IPMTs were of branch type with a mean diameter of 3.0 cm. The IPMT was located in the head of the pancreas in 3, body in 2 and tail in the other 2. All the 7 IPMTs were adenoma with mild dysplasia. Two of the 7 patients with DC had in situ carcinoma, 1 minimally invasive carcinoma and the remaining 4 invasive carcinoma. The mean diameter of seven DCs (3.0 cm) with IPMT were smaller than that of 70 DCs (3.6 cm) (8P = 0.0295). Stage (stage I/II/III/IV = 3/0/3/1) of the seven DCs concomitant with IPMT were significantly earlier than that (stage I/II/III/IV = 5/6/28/31) of the other 70 (p = 0.0203). The survival curve of the 7 patients with IPMT and DC was significantly better than that of the 70 with DC alone (p = 0.0460).

Conclusions: Clinicians should pay attention to the possible presence of DC of the pancreas in male patients with intraductal papillary-mucinous adenoma of the pancreas of branch type in their 6th to 8th decades.