Scintigraphic study of palpable breast nodes with 99m Tc-tetrofosmin

In Brazil, breast carcinoma has the greater incidence among women. In 1996, about 31,210 new cases were diagnosed. The purpose of this study is to determine if 99m technetium-tetrofosmin preferentially concentrates within malignant palpable breast nodes, distinguishing them from the benign lumps. Fifth-four consecutive and unsolicited women, mean age 47.5 +- 10.7 years, with palpable nodes in breast, underwent breast scintigraphy with 99m technetium-tetrofosmin and excisional biopsy or fine needle puncture within interval eight weeks. Histopathologic studies demonstrated 13 cysts, 1 cyst with local inflammation, 11 fibroadenoma, 2 fibrodysplasias, 3 fibroadenomas with high cellularity, 1 fibrocystic change with local inflammation, 23 invasive intraductal carcinomas and 1 invasive lobular carcinoma. The nodes ranged from 10 to 100 mm in greater diameter. The scintigraphic study yielded 30 true-negative cases, 24 true-positives, no false-negative and 1 false-positive. This case was a fibrocystic lump with local inflammation. Two patients had metastases in axillary lymph nodes, well detected in scintigraphy. The statistic analysis showed: sensitivity, 100%; specificity, 96.8%; accuracy, 98.2%; negative predictive value, 100%; positive predictive value, 96.0%. Nonparametric tests of Fisher and Chi-square rejected the antithesis at a confidence interval of 99.9% (p < 0.001). We concluded that 99m technetium-tetrofosmin preferentially concentrates in malignant palpable breast nodes and can help to distinguish them from the benign tumors with with very high accuracy. (author)