Characteristics and diagnostic value of multi-slice spiral computed tomography examination of gastrointestinal lipoma

Abstract

Objective To investigate the characteristics and diagnostic value of multi-slice spiral computed tomography (MSCT) examination of gastrointestinal lipoma. Methods The cross-sectional study was adopted.The clinicopathological data of 96 patients with gastrointestinal lipoma including 32 from the Second Hospital Affiliated to Wenzhou Medical University, 30 from the First Hospital Affiliated to Wenzhou Medical University, 17 from the Ruian People's Hospital of Zhejiang, 11 from the Yueqing People's Hospital, 3 from the Wenzhou Central Hospital and 3 from the Wenzhou People's Hospital from December 2006 to September 2015 were collected. All patients were fasted for 8 hours prior to the examination, and partial patients underwent enhanced scan after the conventional CT scanning with breathless scanning and no abdominal pressure. Coronal and sagittal images of gastrointestinal tract including the tumor were administrated with planar reconstruction (MPR) techniques of Reformat software. Based on MPR images, the curves along the gastrointestinal tract were drawn, voxel distributed along the curve track were reconstructed, and curved planar reconstruction (CPR) images were obtained. The patients received operation or follow-up according to individual characteristics after examinations. The patients undergoing operation were followed up for detecting tumor recurrence and metastasis by CT examination and patients receiving follow-up were observed by endoscopy for detecting changes of tumor size and morphology up to June 2015. The analysis indexes included tumor location and size, performance of MSCT examination (tumor shape, density, margin, intussusceptions, enhanced MSCT examination), intraoperative findings, results of pathological examination and results of follow-up. Measurement data with normal distribution were presented as ±s. Results All the 96 patients received MSCT plain scan and the 42 received enhanced MSCT scan. The CPR images in 30 patients were collected. (1) Tumor location and size: 3 tumors were located in the stomach, 16 in the duodenal, 27 in the jejunum, 23 in the ileal, 2 in the ileocecus, 9 in the sigmoid colon, 9 in the ascending colon, 3 in the descending colon, 3 in the transverse colon and 1 in the appendix. The diameter of tumor was (3.8±2.3)cm. (2) Performance of MSCT examination: of the 96 patients, round or oval tumors were detected in 68 patients, tubular tumors in 15 patients and lobulated tumors in 13 patients. Tumors showed homogeneous density in 67 patients and inhomogeneous density in 29 patients. The CT value of tumors was -110--53 HU with a median value of -80 HU. Tumors of the 96 patients had clear boundaries and smooth margins. Twenty-four patients were complicated with intussusceptions with nested length of (28±4)cm, including 10 cases of multiple concentric rings , 7 cases of double-target sign and 7 cases of banana sign . Enhanced MSCT scan showed that capsule around tumors in the 96 patients demonstrated slightly intensified, tumor body demonstrated no enhancement and that angiolipoma in 10 patients had cable strip like enhancement in the tumors. (3) Intraoperative findings: of the 96 patients, 59 patients underwent surgical resection with single tumor, 24 patients were concomitant with intussusceptions, 9 patients showed aphtha in the center of tumors and 1 patient had partial lipoma in the prepyloric region dropped into the duodenal. Thirty-seven patients received endoscopic examination, showing submucous nodular protrusive lesions of 1.7-3.5 cm. (4) Results of pathological examination: of 59 patients undergoing surgical resection, submucosal, subserous and intramural tumors were detected in 45, 9 and 5 patients, respectively, with complete capsule and pedunculated or non-pedunculated. Of the 59 patients, tumors showed round or oval shape in 41 patients, tubular shape in 10 patients and lobulated shape in 8 patients. The section of tumors showed yellowish-white. Specimens from endoscopic and surgical resections were observed under microscopy, the tumors were composed of mature-differentiated adipocytes, different quantities of fibrous connective tissues, blood vessels and mucus ingredients. Tumor cells were round shape with hypochromatic cytoplast and became polygeal and vacuolated after squeezing, nucleus was compressed to peripheral area and cytoplasm was full of lipid droplets. The results of immunohistochemistry stain showed Vimentin, CD34, D2-40, CD68 were positive and AE1/3 and Calretinin were negative. All tumors were diagnosed as benign lipomas. Fifty-nine patients who underwent surgical resection were followed up for 0.5-5.0 years and 37 patients of which specimens were obstained by endoscopic resection were followed up for 1.0-2.0 years after the pathological diagnosis with no significant change. Conclusion The MSCT finding of the gastrointestinal lipoma has characteristic appearance, and MSCT examination can clearly show lipoma location, size, shape and properties, with a widespread application value. Key words: Lipoma, gastrointestinal tract; Tomography, X-ray computed