CT Findings of Gastrointestinal Stromal Tumor versus Lymphoma of the Small Intestine

PURPOSE: To compare CT features of gastrointestinal stromal tumors (GIST) with those of lymphomas in the small intestine. MATERIALS AND METHODS: CT findings of 11 pathologically confirmed GIST patients and 10 lymphoma patients were retrospectively reviewed. CT findings were analyzed with regard to location, size, margin, growth patterns, internal character, enhancement, invasion, vascular encasement, lymphadenopathy, intestinal obstruction and ascites. RESULTS:An extraluminal mass was present in 82% (9/11) of the GIST patients versus 30% (3/10) of the lymphoma patients. Circumferential wall thickening was observed in 80% (8/10) of the lymphoma patients (p.05). CONCLUSION: Features revealed by CT scans are highly useful in differentiating GIST from lymphoma of the small intestine. Extraluminal growth and internal necrosis or gas are more common in patients with GIST compared with lymphoma. CT features of circumferential wall thickening and associated lymphadenopathy are more common in patients with lymphoma.

Percutaneous Radiofrequency Ablation of Inoperable Primary Lung Cancer

PURPOSE: To present the initial experience of percutaneous radiofrequency ablation (RFA) of inoperable primary lung cancer, and to assess the technical feasibility and potential complications. MATERIALS AND METHODS: Twenty patients with inoperable lung cancer underwent percutaneous RFA. Nineteen of 20 patients had stage III or IV non-small cell lung cancer, and the remaining one had stage I lung cancer with pulmonary dysfunction. The mean tumor size was 4.6+/-0.4 cm (range, 1.8-8.4 cm). RFA was performed with a single (n=18) or cluster (n=2) cool-tip RF electrode and a generator under CT guidance using local anesthesia and conscious sedation. Twenty tumors were treated in 28 sessions. Patients were assessed by contrast-enhanced CT in all cases at 1 week, 1 month, and 3 months. Eleven patients received chemotherapy (n=10) or radiotherapy (n=1) after RFA. RESULTS: RFA was technically successful and well tolerated in all patients. Complete necrosis was attained in 7 lesions (35%), near complete (90-99%) necrosis in 10 lesions (50%), and partial (50-89%) necrosis in 3 lesions (15%). During the mean follow up of 202 days (21 to 481 days), tumor size was decreased in 13 patients, unchanged in 3, and increased in 4. In the latter four, additional RFA was performed. One patient underwent surgery three months after RFA and the histopathologic findings showed a large cavity with thin fibrotic wall suggestive of complete necrosis. During or after the procedure, pneumothorax (n=10), moderate pain (n=4), blood tinged sputum (n=2), and pneumonia (n=2) were developed. Chest tube drainage was required in only 1 patient due to severe pneumothorax. Other patients were managed conservatively. Seven patients died at 61 to 398 days (mean, 230 days) after RFA. The remaining 13 patients were alive 21 to 481 days (mean, 187 days) after RFA. CONCLUSION: RFA appears to be a technically feasible and relatively safe procedure for the cytoreductive treatment of inoperable, non-small cell lung cancer and warrants further investigation as a complementary treatment to chemotherapy or radiation therapy.