Background: Pancreatic mucinous cystic neoplasms (MCN) are rare mucin-producing cystic tumors. They are predominantly found, incidentally, in middle-aged women and usually located in the pancreatic body or tail. They are differentiated from other mucin producing neoplasms by the presence of ovarian-type stroma. The current management of MCN is defined by the consensus European, International Association of Pancreatology (IAP) and the American Association of Gastroenterology guidelines. However, the malignant potential of these lesions remains uncertain, with differing rates of malignant potential being described. Since the criteria for surgical resection differs between the current guidelines, the aims of this large multi-institution study were to determine the rate of associated malignancy in resected MCNs and to determine predictor features, clinical and radiological, for malignant transformation in MCN. Methods: All surgically resected MCNs between January 2003 and December 2015 were included in this international multicentre retrospective study. Lesions without ovarian type stroma were excluded. All lesions found in men had the diagnosis of MCN confirmed by two experienced pancreatic pathologists. Malignant MCNs were defined by the presence of invasive adenocarcinoma. Results: 211 patients with a confirmed and surgically resected MCN were included. Median age was 53 (range 18–82) years, and 95.7% (202/211) were in women. Median pre-operative tumour size was 52 (range 12-230) mm. 16.1% (34/211) were malignant. The rates of malignancy (33.3% (3/9) vs. 15.3% (31/202)) and high-grade dysplasia (33.3% (3/9) vs. 15.8% (32/202) were double in men compared to women. In all cases of malignancy or high-grade dysplasia, at least one of the following characteristics was seen: male patient, symptoms, or a preoperative worrisome feature (solid component, septations, main pancreatic duct dilatation >6mm, elevated serum ca 19-9). A total of five cases of malignant transformation occurred in MCNs less than 4 cm in size. All these cases were associated with features of concern on pre-operative cross-sectional imaging. Conclusion: In female patients in this large multicentre study, malignancy or high-grade dysplasia was solely seen in MCNs with symptoms or worrisome features on preoperative imaging, regardless of the size of the tumour. In males, the risk of malignancy was significantly higher than in females, suggesting that operative treatment should be considered in all male patients with a suspected MCN of any size. In female patients, conservative management seems to be a safe approach for suspected MCNs of any size without symptoms or worrisome features.

Surgical management of Pancreatic Mucinous Cystic Neoplasms (MCNs)

SHAMALI, Awad
2017-01-01

Abstract

Background: Pancreatic mucinous cystic neoplasms (MCN) are rare mucin-producing cystic tumors. They are predominantly found, incidentally, in middle-aged women and usually located in the pancreatic body or tail. They are differentiated from other mucin producing neoplasms by the presence of ovarian-type stroma. The current management of MCN is defined by the consensus European, International Association of Pancreatology (IAP) and the American Association of Gastroenterology guidelines. However, the malignant potential of these lesions remains uncertain, with differing rates of malignant potential being described. Since the criteria for surgical resection differs between the current guidelines, the aims of this large multi-institution study were to determine the rate of associated malignancy in resected MCNs and to determine predictor features, clinical and radiological, for malignant transformation in MCN. Methods: All surgically resected MCNs between January 2003 and December 2015 were included in this international multicentre retrospective study. Lesions without ovarian type stroma were excluded. All lesions found in men had the diagnosis of MCN confirmed by two experienced pancreatic pathologists. Malignant MCNs were defined by the presence of invasive adenocarcinoma. Results: 211 patients with a confirmed and surgically resected MCN were included. Median age was 53 (range 18–82) years, and 95.7% (202/211) were in women. Median pre-operative tumour size was 52 (range 12-230) mm. 16.1% (34/211) were malignant. The rates of malignancy (33.3% (3/9) vs. 15.3% (31/202)) and high-grade dysplasia (33.3% (3/9) vs. 15.8% (32/202) were double in men compared to women. In all cases of malignancy or high-grade dysplasia, at least one of the following characteristics was seen: male patient, symptoms, or a preoperative worrisome feature (solid component, septations, main pancreatic duct dilatation >6mm, elevated serum ca 19-9). A total of five cases of malignant transformation occurred in MCNs less than 4 cm in size. All these cases were associated with features of concern on pre-operative cross-sectional imaging. Conclusion: In female patients in this large multicentre study, malignancy or high-grade dysplasia was solely seen in MCNs with symptoms or worrisome features on preoperative imaging, regardless of the size of the tumour. In males, the risk of malignancy was significantly higher than in females, suggesting that operative treatment should be considered in all male patients with a suspected MCN of any size. In female patients, conservative management seems to be a safe approach for suspected MCNs of any size without symptoms or worrisome features.
2017
MCNs, Pancreatic resection, Malignancy
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Descrizione: Phd Thesis Shamali A.
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Utilizza questo identificativo per citare o creare un link a questo documento: https://hdl.handle.net/11562/961830
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