The lymph node micrometastasis was retrospectively immunohistochemical
ly investigated in 185 patients with node-negative breast cancer and c
ompared with the routine conventional findings. The monoclonal antibod
ies to epithelial membrane antigen (EMA) and mucinous-like carcinoma a
ntigen (MCA) were used. Of 19 EMA-positive cases, 16 were false positi
ve. Therefore only 3 cases were found to show staining with both EMA a
nd MCA. The patients are all living and well and free of recurrence. N
o micrometastasis was immunhistochemically demonstrated in 11 node-neg
ative breast cancer patients with subsequent metastases. The results o
f the present study indicate that the detection rate containing occult
cells afforded by conventional routine evaluation is sufficient, at l
east in Japanese.