Mucinous Cystic Neoplasm of the Pancreas or Intraductal Papillary-mucinous Tumour of the Pancreas

OBJECTIVE: To compare clinicopathological findings in patients with mucinous cystic neoplasms and intraductal papillary-mucinous tumours. DESIGN: Retrospective study. SETTING: University department of surgery, Japan. SUBJECTS: 21 patients with mucinous cystic neoplasms (group 1) and 48 with intraductal papillary-mucinous tumours (group 2). RESULTS: The mean age was younger in group 1 (53(3.4) years) than in group 2 (65(1) years, p < 0.0001). The male:female ratio was smaller in group 1 than in group 2, being 0.17 (3/18) and 1.4 (28/20), respectively, (p = 0.0007). The main sites of the lesions were also significantly different: in group 1 four (19%) were located in the head and 17 in the body or tail, while 32 (67%) were in the head of the pancreas and 16 (33%) in the body or tail in group 2 (p = 0.0007). A unique endoscopic finding, excretion of mucin from the patulous orifice of the papilla, was present in two (9%) of the 21 mucinous cystic tumours and in 21 (45%) of the 47 intraductal papillary-mucinous tumours examined (p = 0.006). Metachronous or synchronous malignant diseases were found in the pancreas or other organs in one (5%) of the 21 patients with mucinous cystic neoplasm and in 13 (27%) of the 48 with intraductal papillary-mucinous tumours (p = 0.03). The three- and five-year survival rates of 11 patients with mucinous cystadenocarcinoma were 45% and 27%, while those of 15 with intraductal papillary-mucinous carcinoma were 85% and 42%. CONCLUSIONS: These findings suggest that mucinous cystic neoplasm and intraductal papillary-mucinous tumours are different clinicopathological entities. Aggressive surgery with peripancreatic lymph node dissection is recommended, particularly for mucinous cystadenocarcinoma, and postoperative follow-up with attention given to the presence of other malignancy is necessary as well as to local recurrence and haematogenous spread.