Pathology of primary tumors and axillary lymph nodes in British and Japanese women with breast cancer.

Histopathologic features of the primary tumor and axillary lymph nodes from 97 consecutive patients with breast cancer from Japan were compared with those from 164 patients from England. Between the two groups, there were statistically significant differences in the morphology of the primary tumors regarding nuclear grade and patterns of tumor infiltration. In axillary lymph nodes, sinus histiocytosis was much more common in Japanese cases than in British cases, and was related to a diminished frequency of axillary node metastases. Germinal centers were also more common in the nodes of Japanese patients and were similarly associated with diminished frequency of metastases.