Relevance of gene mutations and methylation to the growth of pancreatic intraductal papillary mucinous neoplasms based on pyrosequencing

We aimed to assess some of the potential genetic pathways for cancer development from non-malignant intraductal papillary mucinous neoplasm (IPMN) by evaluating genetic mutations and methylation. In total, 46 dissected regions in 33 IPMN cases were analyzed and compared between malignant-potential and benign cases, or between malignant-potential and benign tissue dissected regions including low-grade IPMN dissected regions accompanied by malignant-potential regions. Several gene mutations, gene methylations, and proteins were assessed by pyrosequencing and immunohistochemical analysis. RASSF1A methylation was more frequent in malignant-potential dissected regions (p = 0.0329). LINE-1 methylation was inversely correlated with GNAS mutation (r = − 0.3739, p = 0.0105). In cases with malignant-potential dissected regions, GNAS mutation was associated with less frequent perivascular invasion (p = 0.0128), perineural invasion (p = 0.0377), and lymph node metastasis (p = 0.0377) but significantly longer overall survival, compared to malignant-potential cases without GNAS mutation (p = 0.0419). The presence of concordant KRAS and GNAS mutations in the malignant-potential and benign dissected regions were more frequent among branch-duct IPMN cases than among the other types (p = 0.0319). Methylation of RASSF1A, CDKN2A, and LINE-1 and GNAS mutation may be relevant to cancer development, IPMN subtypes, and cancer prognosis.

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

Background Colloid carcinoma derived from intraductal papillary mucinous neoplasm (IPMN) of the pancreatic head with prominent calcification is exceedingly rare. Only a few studies about this entity have been reported in the literature. Therefore, its biological behavior, appropriate treatment modalities, and overall patient prognosis remain largely unclear. In this report, we present a case of a resected colloid carcinoma derived from IPMN with prominent calcification. In addition, we review the relevant literature and discuss the clinical management of colloid carcinoma derived from IPMN with prominent calcification, including the histopathological features. Case presentation A 75-year-old man presented with a pancreatic tumor measuring 58 mm on the head of the pancreas that was incidentally detected by abdominal ultrasonography. Abdominal computed tomography and endosonography revealed a multilobular cystic lesion with a 17 mm mural nodule in the pancreatic head. Furthermore, prominent calcification was observed on part of the cyst wall. Magnetic resonance cholangiopancreatography showed a multilobular cyst in the branch duct lacking communication between the cystic lesion and the main pancreatic duct. Thus, the lesion was diagnosed as intraductal papillary mucinous carcinoma (IPMC) with a preoperative classification of T1N0M0 stage IA according to the 8th Union for International Cancer Control (UICC) guidelines, and the patient underwent conventional pancreatoduodenectomy. The resected specimen was microscopically found to contain colloid carcinoma, probably derived from IPMN. In addition, marked calcification was confirmed in the partition wall of the cystic mass. The postoperative course was uneventful, and no evidence of recurrence or metastasis was observed after 10 months of follow-up. Conclusions We consider that colloid carcinoma derived from IPMN should be differentially diagnosed as a pancreatic multilobular cystic lesion with prominent calcification that shows no sign of systemic chronic pancreatitis.

Low HDL-Cholesterol is Associated with Malignant Intraductal Papillary Mucinous Neoplasms: A Multicenter Study

Background: Intraductal papillary mucinous neoplasms (IPMNs) has the potential of malignant transformation. Previous studies showed that HDL-c was related to risk of cancer. In this study, we showed the association between HDL-c and the incidence of malignancy in IPMNs.Material and methods: 226 patients with histologically proven IPMNs who underwent surgery were included in the present study. 151 patients were assigned to training group andother 75 patients was set as a validation. Patients’ demographic information, clinical data, and pathological features were obtained from medical records. Those with high grade dysplasia and invasive carcinoma were defined as malignant IPMNs. Logistic regression analyses were used to show the association between HDL-cand malignant IPMNs. Receiver operating characteristic (ROC) curves were performed to show the predictive performance. Results: Prevalence of low HDL-c in patients with malignant IPMNs was higher than those with non-malignant IPMNs (p < 0.01) both in training group and validation group. Prevalence of malignant IPMNs was decreased with the increase of HDL-c both in all IPMNs and Branch-Duct IPMNs (BD-IPMNs).Logistic analysis showed that low HDL-c was associated with malignant IPMNs (OR =20.56, 95% CI:2.58 - 163.64) in all IPMNs and BD-IPMNs (OR = 17.6, 95%CI: 1.16-268.46).The predictive performance of mural nodule plus low HDL-c was higher than that of mural nodule alone or mural nodule plus cyst size in identifying malignant BD-IPMNs.Conclusion: HDL-c may be a potential biomarker for identifying malignant IPMNs. Moreover, HDL-c may improve the predictive ability of malignancy in BD-IPMNs.