SMALL (1.5 CM OR LESS) LIVER METASTASES - US-GUIDED BIOPSY

PURPOSE: To determine the techniques used for and the success of ultra sound (US)-guided biopsy of hepatic metastases 1.5 cm in diameter or s maller. MATERIALS AND METHODS: A computer search of radiology reports identified 29 patients who underwent US-guided biopsy of 30 hepatic ma sses 1.5 cm in diameter or smaller suspected to be metastases. All 30 lesions were sampled for biopsy with the free-hand technique. Paramete rs assessed were lesion size and location, needle size, transducer typ e, number of passes made, cytologic or histologic analysis, and final histologic diagnosis. Biopsies were considered successful if a positiv e histologic diagnosis of metastasis was made. RESULTS: The mean lesio n diameter was 1.3 cm (range, 0.9-1.5 cm). Lesion depth was 3-9 cm (me an, 5 cm). Twenty biopsies were performed with a 22-gauge aspirating n eedle and analyzed cytologically. An average of 2.7 passes were made p er lesion. Phased-array sector transducers were used in 23 lesions. In 28 (93%) lesions and 28 (96%) patients, an adequate specimen was obta ined to establish the histologic diagnosis of metastatic disease. CONC LUSION: US appears to be an effective guidance technique for biopsy of small liver metastases.