Breast carcinoma presenting as axillary metastases without evidence of a primary tumor

Abstract

Background. Sixty cases of axillary metastases from clinically occult breast cancer were analyzed. All cases had histologic evidence of metastatic nodes compatible with breast carcinoma. Methods. Thirty‐three patients underwent breast surgery at the time of histologic diagnosis of the axillary metastases, 6 patients were treated with radiation therapy to the breast, and 17 patients did not receive any immediate treatment of the breast carcinoma (9 of these subsequently had a primary breast carcinoma) during the follow‐up. Thirty‐seven of 60 patients underwent adjuvant therapy (29 underwent chemotherapy and 8 underwent tamoxifen therapy). From the histologic point of view, the number of metastatic nodes was 1 in 13 patients, 2 to 3 in 10 patients, and 4 or more in 23 patients; the number of metastatic nodes was not evaluable in 14 cases. Invasion was extranodal in 92% of cases. Eighty‐six percent of cases were histologically classified as Grade 3 according to Bloom and Richardson. Results. The 5‐year and 10‐year survival rates were 77% and 58%, respectively. The comparison between the survival curves of the patients treated with immediate surgery/radiation therapy and of the patients whose cases were followed‐up without treatment to the breast showed no difference. Adjuvant treatments did not improve prognoses. Conclusions. The coexistence of a minimal (or unidentifiable) primary carcinoma with an extensive involvement of axillary nodes and a predominance of the undifferentiated histologic type, together with an unexpectedly good prognosis, makes this type of presentation an interesting example of a dissociated host resistance. Cancer 1992; 70:504–508. Copyright © 1992 American Cancer Society