Primary cystic and solid neuroendocrine tumor of the retroperitoneum: A case report.

RATIONALE: Primary neuroendocrine tumors (NETs) of the retroperitoneum are extremely rare. The purpose of this case report is to highlight the unusual growth pattern and radiologic features of primary retroperitoneal NETs. PATIENT CONCERNS: A 46-year-old woman was found to have a retroperitoneal cystic and solid mass during a physical checkup. DIAGNOSES: The mass was mainly multiseptated in the cystic portion and had a bead-like, lobulated appearance. The solid portion showed restricted diffusion on diffusion-weighted imaging and obvious homogeneous enhancement. The cystic portion showed ring-like and septal enhancement. The patient was diagnosed with a grade 2 (G2) NET of the retroperitoneum after surgery. INTERVENTIONS: The patient underwent resection of the large retroperitoneal tumor. OUTCOMES: The patient returned 20 months later with tumor recurrence in the retroperitoneum. She was enrolled in a clinical trial for sulfatinib, and the mass was considerably reduced in size after 4 months. During a nearly 1.5-year follow-up, the mass gradually became slightly enlarged. The expression of somatostatin receptor 2 (SSTR2) was detected, and somatuline was administered as the current treatment. LESSONS SUBSECTIONS: When a retroperitoneal mass presents as a well-defined cystic or solid hypervascular mass with a fibrous capsule, a primary retroperitoneal NET should be considered in the differential diagnosis.

Contrast-enhanced multiple-phase imaging features of intrahepatic mass-forming cholangiocarcinoma and hepatocellular carcinoma with cirrhosis: A comparative study.

The intrahepatic mass-forming cholangiocarcinoma (IMCC) is frequently misdiagnosed as hepatocellular carcinoma (HCC) in patients with cirrhosis, by numerous radiologists and clinical doctors, which results in the incorrect therapeutic treatment. A retrospective case-control study was conducted, and the contrast-enhanced multiple-phase (CEMP) computed tomography (CT) and magnetic resonance imaging (MRI) findings of 22 pathologically confirmed IMCC patients and 22 HCC controls with underlying liver cirrhosis were analyzed at the present hospital, from January 2010 to December 2015. In addition, serum tests were conducted and clinical symptoms of patients evaluated. A statistical analysis revealed that the enhancement pattern, signal on MRI delayed phase (P<0.001), maximum diameter, capsule retraction, portal vein invasion, bile duct dilation and abdominal lymphadenectasis characteristics were different between IMCC and HCC patients with cirrhosis. On CEMP CT and MRI analysis, the most frequently occurring enhancement patterns of IMCC were progressive patterns (P=0.001 or P<0.001). Conversely, the most frequently occurring enhancement patterns present in HCC were the washout patterns (P<0.001). Therefore, the diagnosis of IMCC in cirrhotic patients should be verified with CEMP CT and MRI analysis for the future, to determine presence or absence of progressive and/or peripheral rim-like enhancement, a hyperintensive delayed phase with capsule retraction, portal vein invasion, bile duct dilation, abdominal lymphadenectasis and increased levels of CA199.