Carcinoma in situ of the pancreas with fibrosis area around the carcinoma: A case report

RATIONALE: Pancreatic cancer (PC) has the worst prognosis among all carcinomas. However, patients with carcinoma in situ (CIS) of the pancreas, usually, have a good prognosis. Many previous reports have mentioned the high frequency of fibrosis around CIS. In some cases, the fibrosis is detected on endoscopic ultrasonography (EUS), but there are few past reports of fibrosis detected on computed tomography (CT). PATIENT CONCERNS: We encountered a case of fibrosis around CIS detected by CT. A 74-year-old man was being followed for chronic hepatitis C. On a contrast-enhanced CT (CE-CT), a space-occupied lesion (7 mm in size) in the pancreatic head was identified in the delayed phase. DIAGNOSIS: It was shown to be a hypo echoic lesion in EUS, and EUS-fine-needle aspiration was performed. Cytological examination revealed abnormal cells suspicious for a neuroendocrine tumor. INTERVENTIONS: Consequently, a pancreaticoduodenectomy was performed. Histopathological examination showed CIS in the branch duct with 10 mm of fibrosis around CIS. The fibrotic area corresponded to the mass detected by preoperative CE-CT. OUTCOMES: He had no relapse of PC but died 2 years later from another cause. LESSONS: This case highlights the importance of identifying the enhanced area in the delayed phase on CE-CT, as this can be fibrosis around CIS.