[Benign and malignant gastric ulcer: CT findings]. / Aspetti delle ulcere benigne e maligne dello stomaco in tomografia computerizzata.

ABSTRACT

PURPOSE: To evaluate the differential CT aspects of benign and malignant gastric ulcers. MATERIALS AND METHODS: We retrospectively reviewed the CT findings of 54 patients with gastric ulcerative lesions, 47 with malignant lesions (38 adenocarcinomas, 9 lymphomas) and 7 with benign lesions. All patients underwent histological examination. CT scanning was performed with a helical scanner Picker PQ 2000, before and after intravenous contrast material administration and after adequate stomach distension, achieved by drinking at least 400 ml of water; 2 ml/kg of intravenous contrast was injected at a rate of 3.5 ml/s. After contrast administration two-phase dynamic scans were performed with a scan delay of 30O and 50O. The parameters considered were lesion size and localization, extension of the ulcer into or beyond the body of the stomach, focal wall thickness, contrast enhancement of the ulcer, perigastric tissue morphology, presence of lymphoadenopathies and liver metastases. RESULTS: The ulcer size and localization were not significative in the differential diagnosis of benign or malignant ulcers. In 46 patients the ulcer extended within the body of the stomach (38 adenocarcinomas and 8 lymphomas), in 8 cases beyond (7 benign ulcers and 1 initial lymphoma). In 46 cases of malignant ulcers there were focal wall thickenings (> 5mm), in 1 case of initial lymphoma and in all cases of benign ulcers the thickness of the wall was normal. Contrast enhancement of the lesion was observed in 25 cases, all of which were adenocarcinomas. 33 patients had perigastric tissue abnormalites (32 with malignant lesions and 1 with benign ulcer). Lymphoadenopathies and liver metastases were detected in 30 cases and always associated to malignant ulcers. DISCUSSION AND CONCLUSIONS: The improved CT technology allows to recognize gastric ulcer. Ulcer extension into stomach body; focal wall thickening; contrast enhancement of the lesion, lymphoadenopaties and liver metastases are significative in malignant gastric ulcers. The lack of these abnormalities is characteristic of benign gastric ulcers but can be also observed in early malignant lesions.