BREAST-CANCER STAGING USING TC-99M SESTAMIBI AND IN-111 PENTETREOTIDESINGLE-PHOTON EMISSION TOMOGRAPHY

We evaluated the clinical usefulness of single-photon emission tomogra phy (SPET) with technetium-99m sestamibi and indium-lll pentetreotide in breast cancer staging. Fifteen patients with clinical and/or mammog raphic findings suggesting Tl-2NO-1 breast cancer were studied. SPET i mages were acquired 20 min after Tc-99m-sestamibi injection and 4 and 24 h after In-111-pentetreotide injection. Patients underwent surgery the day after the later In-111-pentetreotide acquisition. Pathological examination showed 16 tumours in the 15 patients, with one bilateral carcinoma. The mean tumour diameter was 18.7 mm. Metastatic axillary i nvolvement was found in 6/16 tumours, with a mean of five metastatic n odes per axilla. Both tracers correctly identified 15/16 primary tumou rs and five of the six cases of metastatic axillary node involvement. No difference between the tracers was observed in breast cancer stagin g. Tc-99m-sestamibi seems to be the better tracer in terms of physical characteristics, execution time and cost-effectiveness. Our data sugg est the future possibility of using nuclear medicine imaging to avoid axillary dissection in patients with Tl breast cancer.