Nerve growth factor receptor immunoreactivity in breast cancer patients.

Nerve growth factor receptor (NGF-R) has been shown to have antiproliferative, differentiative, or apoptotic effects on some types of tumor cells, whereas in others it may have mitogenic activity. The immunohistochemical distribution of NGF-R was analyzed in a series of tissue samples from breast cancer patients and its relationship with other clinical and pathological parameters was studied. The distribution of NGF-R was evaluated by immunohistochemistry in frozen tissue samples of 46 breast cancer patients (ME20-4 monoclonal anti-NGF-R). NGF-R immunoreactivity was localized in the plasma membrane of myoepithelial cells, differentiated ducts, neoplastic cells, blood vessels, and nerve fibers in 26 patients (57\%). Less differentiated neoplastic tissues were usually NGF-R negative. NGF-R immunoreactivity was associated with estrogen receptor (ER) status (p = 0.02), small tumor dimension (pT) (p = 0.04), low histologic grade (G1-G2) (p < 0.05), old age (p = 0.02), menopause (p = 0.02), and long disease-free survival (DFS) (median follow up 86 months; p = 0.03; independently from ER, pT, age, menopause by multivariate analysis, p = 0.0078). The expression of NGF-R immunoreactivity by breast cancer patients with long DFS may represent a crucial step both in the differentiation status of neoplasia and in the host immune mechanism controlling tumor growth and metastasization.