Colloid Carcinoma of the Pancreas: Case Report and Review of the Literature

Abstract

Background: Colloid carcinoma of the pancreas is a rare type of pancreatic cancer that has a more indolent course and superior long-term survival compared to ductal adenocarcinoma. There is a dearth of literature describing this diagnosis due to its rarity and its only recent recognition as a distinct clinical entity. We present two cases of patients with colloid carcinoma and discuss the presentation and management of this disease.Case Presentation: A 58-year-old man with repeated bouts of pancreatitis and a 72-year-old woman with symptoms of pancreatic exocrine and endocrine insufficiency were both found to have cystic masses in the head of the pancreas. Both were identified as having at least mixed main duct/side branch intraductal papillary mucinous neoplasms (IPMNs) on appropriate workup with additional imaging and endoscopy. Pancreaticoduodenectomy was recommended. Both patients, however, were noted to have high-grade dysplasia at the resection margin intraoperatively on frozen section, and thus, total pancreatectomies were performed. Final pathology in each case demonstrated colloid carcinoma with no nodal spread of disease. The patients recovered well. Adjuvant chemotherapy was recommended.Conclusion: Colloid carcinoma of the pancreas is a rare pathologic diagnosis and is frequently associated with IPMN. Colloid carcinomas tend to present at earlier stages than do ductal adenocarcinomas and are known to have improved long-term survival. Surgical and systemic options for treatment parallel that of ductal adenocarcinoma due to the rarity of the diagnosis and the lack of trials assessing therapy for this specific diagnosis.

Colloid Carcinoma of the Pancreas: A Case Report

“…Most CC occurs in the context of IPMN, especially in close relation to intestinal type IPMN, as well as gastric type, pancreatic bile duct type and eosinophilic type [3,7] . Most studies have shown that CC has a better prognosis than other pancreatic cancers, with a 5-year survival rate of 28-55% compared with 5-12% for pancreatic cancers [2,8,9] . Currently, the main reasons are as follows: CC and IPMN usually rich in sticky protein 2 (MUC2), and contains no sticky protein 1 ((MUC1)),but PDAC express MUC1 strongly and lack of MUC2, MUC2 epithelial cells as a barrier to inhibit invasion of tumor cells to prevent further spread, which has a tumor suppressor activity, at the same time, the CC, mismatch repair gene mutation and microsatellite instability frequency is lower, so CC and IPMN malignant degree lower [10][11][12][13] , so there is even some lymph node metastasis is still alive and disease-free survival in 10 years' time [13] .…”

“…Currently, the main reasons are as follows: CC and IPMN usually rich in sticky protein 2 (MUC2), and contains no sticky protein 1 ((MUC1)),but PDAC express MUC1 strongly and lack of MUC2, MUC2 epithelial cells as a barrier to inhibit invasion of tumor cells to prevent further spread, which has a tumor suppressor activity, at the same time, the CC, mismatch repair gene mutation and microsatellite instability frequency is lower, so CC and IPMN malignant degree lower [10][11][12][13] , so there is even some lymph node metastasis is still alive and disease-free survival in 10 years' time [13] . Another potential reason for the better prognosis of CC is cellular change: colloidal carcinoma cells exhibit reverse polarization,the cell base secretes mucins toward the cell-matrix interface (rather than into the lumen), thereby separating the cells from the underlying matrix [9] . Meanwhile, lower T stage, fewer lymph node metastases,highly differentiated tumors, and fewer vascular and nerve invasion are also considered to be one of the reasons for the better prognosis of CC [10] .…”

“…At present, there is no treatment guidelines for CC, because of its rarity and morphology characterized by malignant, its treatment strategy follows the PDAC, for without distant organ metastasis and vascular invasion, have suggested that surgical resection, surgical procedure depends on the size and location of the tumor,operation methods includ pancreaticoduodenectomy, total pancreatectomy and distal pancreatectomy [4,8,9] . Since most CC are accompanied by IPMN, it has been proposed that if IPMN is found in the surgical margin of CC after surgery, a second operation should be performed to ensure the therapeutic effect [7] .…”

Colloid carcinoma derived from intraductal papillary mucinous neoplasm of the pancreatic head with calcification: A case report and literature review

“…Colloid carcinoma represents approximately 1% of pancreatic cancers [ 6 , 7 ]. They are described as a histopathological variant of ductal adenocarcinoma, which is characterized by the presence of large pools of extracellular mucin containing neoplastic cells.…”

“…They are described as a histopathological variant of ductal adenocarcinoma, which is characterized by the presence of large pools of extracellular mucin containing neoplastic cells. The mucin component comprises at least 50% colloid carcinoma (according to the definition by the World Health Organization) or at least 80% of the tumor (according to the US Armed Forces Institute of Pathology) [ 6 , 7 ]. In almost all cases, colloid carcinoma develops from pre-existing intraductal papillary mucinous neoplasms, especially those forming intestinal-type papillae, and is characterized by MUC2 expression, which is rarely found in pancreatic ductal carcinoma [ 6 , 7 ].…”