SOLITARY PULMONARY METASTASIS IN ADVANCED LOCAL MALIGNANT MELANOMAS

Abstract

Object: That computed tomography can detect more pulmonary nodules of all types than can conventional tomography and plain radiography has been established. Whether such information is clinically relevant has not. To determine the clinical potential of CT in a pure patient population with high propensity for pulmonary metastases a prospective trial was developed for locally advanced malignant melanoma. Materials and Procedures: Forty-two patients with Clark stage IV or V melanoma underwent high KVp chest radiography, whole lung linear tomography and computed tomography with machines of 5 second scanning times. Twelve of the 21 patients found to have abnormal CT scans had subsequent scans 2–6 months later. Results: Of the 42 patients 21 disclosed “definite” abnormalities, 11 by chest radiography, 16 by conventional tomography and 21 by CT. CT detected solitary pulmonary nodules in three of 16 patients with normal plain films (19%). Of 15 others with suspicious findings on plain films, CT disclosed one or more nodules in 7 (47%), one of whom had negative conventional tomograms. Of the 11 patients with a solitary plain chest nodule, CT revealed multiple nodules in 5 (46%), 4 more than conventional tomography. In all, eleven patients showed CT abnormalities not detected by conventional tomography. Based on these CT findings 21 patients without demonstrable visceral metastases received immunotherapy, 20 with nodules received chemotherapy and one person manifesting a favorable tumor doubling time underwent wedge resection of the metastasis which had been initially demonstrated soley by CT. Conclusions: Although this prospective study is limited by the paucity of ultimate pathologic correlation, it does suggest that computed tomography can have a major clinical impact in assigning treatment options for patients with advanced malignancy showing a proclivity for pulmonary metastases.