PREDICTION OF RESPONSE TO NEOADJUVANT CHEMOENDOCRINE THERAPY IN PRIMARY BREAST CARCINOMAS

Our aim was to determine whether biological molecular markers can pred ict response to neoadjuvant chemoendocrine therapy in patients with ea rly breast cancer. Ninety patients (median age 56 years; range, 28-69 years) with primary operable breast carcinoma were studied. They were treated with four 3-weekly cycles of chemotherapy with mitozantrone, m ethotrexate (+/- mitomycin C), and tamoxifen prior to surgery. Fine-ne edle aspiration was used to obtain samples from patients prior to ther apy, and the following parameters were assessed: estrogen receptor (ER ), progesterone receptor (PgR), p53, Ki67, Bcl-2, and c-erbB-2 measure d by immunocytochemistry, and ploidy and S-phase fraction (SPF) by flo w cytometry. The tumors of 78% of the subjects responded (complete res ponse, 9%; partial response, 69%) and 22% did not (no change, 20%; pro gressive disease, 2%). Response rates according to disease stage and p atient age were as follows: T1, 74%; T2, 79%; T3/T4, 78%; age less tha n or equal to 50 years, 76%; >50, 79% (P = not significant). Response rates for other parameters were as follows: ER-positive, 82%, and -neg ative, 70%; PgR-positive, 86%, and -negative, 71%; p53-positive, 74%, and -negative, 81%; Bcl-2-positive, 85%, and -negative 61%; c-erbB-2-p ositive, 57%, and -negative, 93%; Ki67 high, 77%, and low, 81%; SPF hi gh, 77%, and low, 77%; aneuploid, 71%; and diploid, 85%. Only the diff erence for c-erbB-2 was statistically significant (P = 0.007). A trend for higher response rates to neoadjuvant chemoendocrine therapy for t umors that were positive for ER, PgR, and Bcl-2 was observed but did n ot reach statistical significance. Tumors negative for c-erbB-2 had a higher response rate, which was statistically significant. In contrast , Ki67, ploidy, SPF, and p53 failed to predict for response.