DETECTION OF RECURRENT MALIGNANT-MELANOMA WITH TC-99M-MIBI SCINTIGRAPHY

Initial reports suggest that Tc-99m-methoxyisobutylisonitrile (MIBI) s canning may be of clinical Value in staging patients with malignant me lanoma. We carried out a study to evaluate the potential of this techn ique in the detection of recurrent disease. Whole-body Tc-99m-MIBI sca ns were performed in 81 patients with a history of a surgically excise d MM: 28 with known recurrent lesions and 53 during follow-up without evidence of disease. Images started 10 min post-injection, using a dos e of 740 MBq. Diagnoses were confirmed by cytological/histological exa mination or at least one conventional imaging modality. Blinded interp retations of the MIBI scans were performed. Whole-body MIBI scanning c orrectly detected 68 (92%) of 74 metastatic lesions in the following s ites: regional lymph nodes (n = 23), non-regional lymph nodes (n = 10) , skin (n = 16), brain/cerebellum (n = 6), lung (n = 8), bone (n = 4) and breast (n = 1). The technique failed to detect three subcutaneous regressive lesions (<1 cm), one liver metastasis, one spleen metastasi s and a case of multiple small lesions of the duodenal mucous membrane . In 14 patients the procedure detected previously unknown metastatic lesions. These results suggest that Tc-99m-MIBI scanning is an effecti ve imaging modality for whole-body screening of metastatic disease in malignant melanoma patients with the potential to influence treatment planning. (C) 1998 Lippincott Williams & Wilkins.