Breast carcinomas detected by thallium-201 scintigraphy.

Thallium-201 chloride scintigrams were made of GR mice bearing transplanted mammary tumours, and of human patients with breast cancer. The studies on the experimental system using GR mouse mammary tumours showed that the oestrogen-responsive tumours incorporated significantly more Tl-201 chloride than the oestrogen non-responsive tumours. In order to investigate the usefulness of Tl-201 chloride scintigraphy for human patients, a study was carried out on 15 women with primary or advanced breast cancer in which Tl-201 chloride scintigraphy was compared with bone scintigraphy using Technetium-99m. The results indicated that Tl-201, chloride scintigraphy was a very useful method for detection of primary breast cancer and metastases, and in some cases it revealed tumour structures not detected by Technetium-99m. We propose that Tl-201 chloride scintigraphy can be a useful method for early diagnosis of breast cancer.