Mucinous Cystic Neoplasm of the Pancreas is Not an Aggressive Entity

Abstract

Objective-Mucinous cystic neoplasms (MCNs) of the pancreas have often been confused with intraductal papillary mucinous neoplasms. We evaluated the clinicopathologic characteristics, prevalence of cancer, and prognosis of a large series of well-characterized MCNs in 2 tertiary centers.Methods-Analysis of 163 patients with resected MCNs, defined by the presence of ovarian stroma and lack of communication with the main pancreatic duct.Results-MCNs were seen mostly in women (95%) and in the distal pancreas (97%); 25% were incidentally discovered. Symptomatic patients typically had mild abdominal pain, but 9% presented with acute pancreatitis. One hundred eighteen patients (72%) had adenoma, 17 (10.5%) borderline tumors, 9 (5.5%) in situ carcinoma, and 19 (12%) invasive carcinoma. Patients with invasive carcinoma were significantly older than those with noninvasive neoplasms (55 vs. 44 years, P = 0.01). Findings associated with malignancy were presence of nodules (P = 0.0001) and diameter ≥60 mm (P = 0.0001). All neoplasms with cancer were either ≥40 mm in size or had nodules. There was no operative mortality and postoperative morbidity was 49%. Median followup was 57 months (range, 4 -233); only patients with invasive carcinoma had recurrence. The 5-year disease-specific survival for noninvasive MCNs was 100%, and for those with invasive cancer, 57%. Conclusions-This PATIENTS AND METHODSThe MGH and UV Institutional Review Boards approved this study. Patients who underwent pancreatic resection between January 1988 and October 2005 for pathologically confirmed MCNs were identified from prospectively collected databases. Both presence of ovarian stroma and lack of communication with the main pancreatic duct were used as criterion to distinguish MCNs from IPMNs. 2,4 In the study period, 567 patients underwent surgery for mucinous tumors of the pancreas (305 MGH and 262 UV). Of these 163 (29%), 102 from UV and 61 from MGH, were determined to have MCNs, whereas the remaining patients had main-duct, branch-duct, or combined IPMNs, or indeterminate mucinous neoplasms. Information including demographics, clinical history, diagnostic work-up, type of surgery, postoperative course, pathology, and long-term follow-up were recorded. Perioperative mortality was defined as in-hospital or 30-day death.Tumors were classified according to the WHO criteria as MCNs with mild dysplasia (adenoma), with moderate dysplasia (borderline neoplasm), with high-grade dysplasia (carcinoma in situ), and MCN with invasive carcinoma. 4 In short, in MCN adenoma, the epithelium shows basally located nuclei with no increase in mitosis. In the borderline MCNs, the epithelium may exhibit papillary projections or crypt-like invagination, some nuclear pseudostratification with crowding and slightly enlarged nuclei. Mitoses can be observed. MCN with noninvasive carcinoma demonstrate high-grade dysplastic epithelial changes. The epithelium often forms papillae and irregular budding, as well as branching with nuclear stratification, severe nuclear a...

Mucinous cystic neoplasms of the liver: a clinicopathological study and comparison with intraductal papillary neoplasms of the bile duct

“…17,18 One possible explanation for this discrepancy is that owing to recent advances in imaging modalities, patients in this study were diagnosed at a younger age; patients with malignant hepatic and pancreatic mucinous cystic neoplasms were older than those with benign cystadenomas. 14,18 This may stress the importance to treat patients with hepatic mucinous cystic neoplasm at a young age to reduce the risk of malignant transformation.…”

Cystic Neoplasms of the Pancreas

“…IPMN are found throughout the gland with 20 to 25 % being multifocal whereas over 95 % of MCN occur in the body or tail of the pancreas and are essentially never multifocal. 9,10 Similarly, SCA and SPN are most often found as isolated lesions. Cystic PanNET are similarly isolated lesions but can be multifocal in patients with MEN I.…”

“…10 A joint study in 163 individuals from the Massachusetts General Hospital and the University of Verona found HGD in 5.5 % and invasive carcinoma in 12 %. 9 One reason for the difference between the older and newer studies is that several of the older studies did not require the presence of ovarian stroma as a prerequisite for the diagnosis of MCN thus likely including side branch IPMN. [27][28][29] The size of the cysts in the more recent studies is also smaller (mean 5.…”

“…6 The survival of patients with low, moderate, or high dysplasia in MCN is excellent with 100 % 5-year diseasespecific survival in two large studies. 9 Survival for those with invasive disease is far lower with 5-year survival of between 0 and 57 %.…”

“…14 Even in patients with metastatic diseases, prognosis remains good with only 18.2 % of patients with metastases dying with a mean follow-up of 6.3 years (range [1][2][3][4][5][6][7][8][9][10][11][12][13][14][15][16]. 31 Postoperative surveillance is normally performed with cross-sectional imaging every 6 months for 2 years and then annually for a total of 5 years.…”