Abstract: Objective:To summarize the features of multislice spiral computed tomography(MSCT) examination for pancreatic adenosquamous carcinoma.
Methods:The clinical data of 19 patients with pancreatic adenosquamous carcinoma who were admitted to the Affiliated Hospital of Ningbo University Medical School and Changhai Hospital from February 2011 to August 2013 were retrospectively analyzed．All the patients received plain and enhanced scan of CT, and the data were transported to the work station for multiplanar reconstruction. The location, size, shape, density,enhancement pattern of tumor, secondary performance, invasion and metastasis were observed. All the  patients received operative treatment and postoperative pathological examinations including observations of gross morphologic and histomorphology, HE staining and immunohistochemistry. All the patients were followed up by outpatient examination and telephone interview till 31 August, 2014.  Measurement data with normal distribution were presented as ±s, and comparison between groups was analyzed by the t test.
Results (1)Ten tumors were located in the pancreatic head, 1 in the pancreatic neck, 3 in the body of pancreas, 1 in the tail of the pancreas and 4 in the body and tail of the pancreas. Tumors of 15 patients showed exophytic growth and tumors of 4 patients showed pancreas straight edges. Tumors were roundlike or ellipse shape in 13 patients and irregular shape in 6 patients. The maximum diameter of tumors was (3.7±1.9)cm (range, 2.0-8.0 cm). The diameter of tumor in the pancreatic head and neck was (2.8±0.9)cm, which was significantly different from (4.9±2.2)cm in the body and tail of pancreas (t=-2.543, P<0.05). (2)Plain CT scan showed that tumors demonstrated low density or slightly low density in 15 patients, isodensity in 4 patients. Nine tumors had necrosis and cystic area, and 10 tumors were solid. There was no hemorrhage and calcinosis in 19 patients.The value of plain CT scan of solid tumors was (36±10)HU. (3)Nine tumors were demonstrated in Ⅱ enhancement, 5 in Ⅳ enhancement, 2 in Ⅲ enhancement like honeycomb, 2 in Ⅲ+Ⅳ enhancement and 1 in Ⅰ enhancement. The CT values of solid tissues of tumors in the arterial phase, ,in the pancreatic parenchyma phase, in the portal venous phase and in the equilibrium phase were (45±9)HU, (55±9)HU, (56±11)HU and (51±15)HU, respectively. (4)Pancreatic duct dilatation caused by tumors was observed in 15 cases, bile duct dilatation in 7 cases, pancreatic atrophy in 3 cases, 11, 2, 9, 8 and 2 patients were complicated with acute pancreatitis, splenic infarction, violations of the surrounding organs, lymph nodes metastases and liver metastases, respectively. (5)All the patients received operation. The results of gross specimen examination showed that tumors were greywhite or greyyellow with invasive growth. Postoperative pathological examination showed that tumors consisted of adenocarcinoma and squamous cell carcinoma. The results of immunohistochemistry showed that CK8/18 or CAM5.2 in the epithelial cell markers and p63 or p40 in the squamous cell markers were positive. Thirteen patients were followed up for (12.0-42.0) months (mean, 9.6 months) and died at the end of followup.
Conclusion:Features of MSCT examination for pancreatic adenosquamous carcinoma include tumor mainly locating at the head of pancreas, necrosis and cystic changes of tumors, low density or slightly low density, pancreatic duct dilatation and violations of the surrounding organs, these can help to diagnose and identify pancreatic adenosquamous carcinoma.