Mucinous cystic neoplasms

Mucinous cystic neoplasms occur almost exclusively in middle-aged women, and are preferentially located in the body and tail of the pancreas. These lesions have malignant potential. The patient age at presentation seems to depend on the degree of malignancy of the neoplasm. Thus, patients with malignant MCN are typically older, suggesting a time-related degeneration of the neoplasm from an initially benign lesion. On pathological examination, the same tumor may simultaneously exhibit all the various degrees of malignant transformation.

An early diagnosis of mucinous cystic neoplasms is essential since the prognosis for patients with the malignant form is the same as for those with ductal adenocarcinoma, while for patients with benign lesions and “in situ” carcinoma surgery could be curative. 

As other cystic neoplasms, mucinous cystic neoplasms are mostly diagnosed incidentally. When present, symptoms are non-specific, and include abdominal discomfort or pain. There may also be non-specific symptoms suggestive of malignancy, such as weight loss, anorexia, and obstructive jaundice.

Two patterns of mucinous cystic neoplasms are seen on diagnostic imaging procedures: macrocystic multilocular and macrocystic unilocular. Thin septae delimit the cystic spaces, and calcifications are a common finding. Large size (>4 cm), a thickened wall, the presence of papillary projections arising from the wall or septae, evidence of peripheral calcifications, and invasion of the surrounding vascular structures are considered signs of malignancy.

When possible, all mucinous cystic neoplasms should be resected. In lesion devoid of malignancy concern, minimally invasive, parenchyma-sparing resections may be proposed. For more information on minimally invasive pancreatic surgery click here. In worrisome or overtly malignant lesions, formal pancreatic resection should be carried out. Patients with small lesions who are not surgically fit may be surveilled, but their long-term outcome is unknown. 

 

Per approfondire:

Crippa S, et al. Ann Surg. 2008;247-571-579.