The diagnosis of internal mammary node metastases of breast cancer.

It is important to know the status of internal mammary lymph node (IMN) in estimating the prognosis in patients with breast cancer and/or planning the treatment. In the first series of this study, the diagnostic value of internal mammary lymphoscintigraphy (IMLS) and that of parasternal sonography (PS) were evaluated in 57 patients. The overall diagnostic accuracy of IMLS was 72% and that of PS, 84%, compared with IMN metastases confirmed on a biopsy. In the second series, 23 patients who underwent extended radical mastectomy and were found to have IMN metastases, were examined for the sizes and locations of metastatic IMN. Minute metastatic lymph nodes not detectable by IMLS or PS were found in 9 (39%) of the patients. However, the incidence of metastases to the first and/or second intercostal spaces was 97% for the patients. We concluded that a biopsy of the first and second intercostal spaces is useful in providing the information of IMN status.