6．漿液性嚢胞腫瘍（SCN）の臨床病理学的特徴

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抄録

Serous cystic neoplasms (SCN), relatively rare cystic tumors representing 1-2% of pancreatic tumors, have small cysts composed of glycogen-rich clear cells in a honeycomb configuration (honeycomb appearance) (microcystic). Recent developments in diagnostic imaging show the characteristic macroscopic morphology. A wide range of cases reveal diverse macroscopic morphology. This lesion is included in the differential diagnosis with other pancreatic lesions having malignant potential. There are a few reports of malignancy, so care must be taken in handling these lesions. The average age ranges from 56.6 to 62.1 years, and 75 to 86% are in women. As many as 53 to 68% have symptoms, the average tumor diameter is about 5cm, and have been reported up to 22cm. These lesions can occur in any part of the pancreas. A typical example of SCN is the microcystic type, which is a collection of microcysts, but there are also macrocystic types in which the constituent cysts are as large as several centimeters and macroscopically show multiloculated cystic tumors. The mixed type is a mixture of both microcystic type and macrocystic types. Although rare, there is also a solid type that looks solid macroscopically. If the lesion exceeds 4cm, aggressive resection is desirable. The most important point regarding diagnosis is that only 53 (61%) of lesions were preoperatively diagnosed as SCN, among 87 patients treated for SCN based on postoperative pathological diagnosis, and in the remaining 34 (39%) SCN was not considered in the diagnosis. Conversely, even if SCN is considered the most likely diagnosis, it may be a different type of tumor. Therefore, for lesions diagnosed as SCN preoperatively, both doctor and patient must consider follow-up without undergoing surgery.