A comparative study of &sup201;Tl and &sup99m;Tc-methoxy-2 isobutyl isonitrile (&sup99m;Tc-MIBI)was performed in 39 breast tumors. &sup201;Tl scintigraphy was carried out in 24 breast tumors and &sup99m; Tc-MIBI scintigraphy in 15. The sensitivity of &sup201;Tl for malignant tumors was 100%(22/22), but specificity was 0%(0/2). On &sup99m;Tc-MIBI scintigraphy, the sensitivity for malignant tumors was 83.3%(10/12) and specificity was 100%(3/3). &sup99m;Tc-MIBI might be more useful for the diagnosis of breast tumors, because the tumor/background ratio of &sup99m;Tc-MIBI was significantly higher than that of &sup201;Tl. In addition, &sup201;Tl scintigraphy and &sup99m;Tc-MIBI scintigrtaphy showed the same degree of accuracy (93.3%) in detecting lymph node metastasis. Moreover, when either ultrasonography (US) with &sup201;Tl or &sup99m;Tc-MIBI scintigraphy was positive for lymph node metastasis, the accuracy of detection became 94.4% The combined use of ultrasonography and scintigraphy might improve the accuracy of diagnosis of lymph node metastasis.
Kubo
H
Departments of Surgery, Jikei University School of Medicine, 3-25-8 Nishishinbashi, Minato-ku, Tokyo 105, Japan.
Fukumitsu
N
Nagata
T
Tomita
H
Tabei
I
Uchida
K
Yamazaki
Y