Pancreatic mucinous cystic neoplasms: a clinicopathological study of 11 cases and detailed review of literature

Abstract

Background Mucinous cystic neoplasms (MCNs) of pancreas are relatively rare, occur almost exclusively in middle-aged females, and are overwhelmingly located in the body and tail of the pancreas, histologically show an ovarian type stroma. MCNs are premalignant, low aggressive tumors. Here we describe the clinicopathologic and radiologic features and follow up of cases diagnosed in our practice. We also present a detailed review of recent literature. Materials and methods Based on strict criteria, 11 cases diagnosed between 2002 and 2016 were included in the study. Results All cases were reviewed histologically. Mean and median age was 46.7 and 46 years respectively. All patients were females and 9 out of 11 cases were located in the body and/or tail of the pancreas. Mean tumor size was 8 cm. Grossly, cysts were uni or multilocular and ranged from a few millimeters to several centimeters in diameter. Microscopically, all cases showed characteristic tall columnar, mucin producing epithelium and ovarian type stroma. Atypia was mild in 8 cases and severe in 3 cases. The latter 3 cases were classified as non-invasive MCNs with high grade dysplasia (2 cases) and MCN with an associated invasive carcinoma (1 case). On immunohistochemistry, all cases showed epithelial positivity for cytokeratin AE1/AE3 and stromal positivity for vimentin and smooth muscle actin. Follow up was available in 7 cases. All patients were alive and well with no recurrence. Conclusions Our cases show features similar to those described in other published studies although cases in our series tended to be larger in number. Since these tumors are relatively rare, premalignant and have strict diagnostic criteria, they must always be considered in the differential diagnosis of pancreatic mucinous cystic lesions. Larger studies incorporating greater number of patients and more detailed follow up will help in increasing our understanding of MCNs.

Neoplasia cística mucinosa do pâncreas

“…Além do mais a NCM do pâncreas apresenta as mesmas características histológicas dos cistos mucinosos ovarianos, que incluem a presença de epitélio colunar secretor de mucina, de receptores de estrogênio e de estroma ovariano. 4,16,17 Talvez isso justifique o motivo desta neoplasia ser observada quase que exclusivamente em mulheres (95%) e com média de idade de 40-50 anos. Alguns autores sugerem que células ovarianas primordiais migram para a cauda pancreática na fase embrionária, predispondo ao desenvolvimento desta neoplasia em uma fase mais tardia da vida.…”

“…Alguns autores sugerem que células ovarianas primordiais migram para a cauda pancreática na fase embrionária, predispondo ao desenvolvimento desta neoplasia em uma fase mais tardia da vida. 4,6,10 Incidência A sua incidência em séries de trabalhos de cirurgia de ressecções de cistos pancreáticos é de 10-45% dos cistos pancreáticos ressecados. 1,18,19 Cerca de 95% das NCM ocorre em mulheres, predominantemente na 5ª e 6ª décadas da vida.…”

“…A incidência das neoplasias císticas do pâncreas aumentou acentuadamente nas 2 últimas décadas, principalmente pelo envelhecimento da população e a disponibilidade crescente de exames de imagem de alta qualidade como a ultrassonografia, a tomografia e a ressonância magnética. [1][2][3][4] Em estudos com exames de imagem, a prevalência das neoplasias císticas do pâncreas varia de 2-20% na população. [5][6][7][8][9][10] Essas neoplasias englobam grupo heterogêneo de tumores benignos, potencialmente malignos (prémalignos) e malignos.…”

Multimodal Therapies against Pancreatic Ductal Adenocarcinoma: A Review on Synergistic Approaches toward Ultimate Nanomedicine Treatments

“…KRAS mutations are believed to be the main drivers of genetic alterations occurring in low grade MCNs, while alterations in p53 tumor suppressor gene take usually place in invasive MCNs. [74] Although some of these mechanisms have been well established, the main issue remains the clinical detection of precursor lesions before their degeneration into PDAC, because even modern high-resolution imaging methods lack the resolution and sensitivity required to detect PanINs smaller than 5 mm and to decipher the diagnostic differentiation of lesions such as IPMN and MCN. [75]…”

“…KRAS mutations are believed to be the main drivers of genetic alterations occurring in low grade MCNs, while alterations in p53 tumor suppressor gene take usually place in invasive MCNs. [ 74 ]…”