METHYL-P-HYDROXYPHENYLLACTATE-ESTERASE ACTIVITY IN BREAST-CANCER - A POTENTIALLY NEW PROGNOSTIC FACTOR IN SHORT-TERM FOLLOW-UP

We assayed methyl-p-hydroxyphenyllactate estrogen (MeHPLAase) activity in 48 cases of primary breast cancer. MeHPLAase activity did not show significant correlation with estrogen receptor and progesterone recep tor levels, No significant relationship was found between enzymatic ac tivity and tumor diameter, lymph node status, mitotic activity, degree of nuclear differentiation, and proportion of the S-phase fraction. D uring the follow-up period (median, 15.8 months; range, 6-69 months), recurrences were observed in 18 of 48 (37%) cases. The Weibull surviva l regression model using the enzymatic activity as a continuous covari ate showed that levels of enzymatic activity were directly associated with the risk of recurrence (P = 0.02). Assuming the mean value of enz ymatic activity as the cutoff value, we found a statistically signific ant relationship between high MeHPLAase activity and shorter recurrenc e-free survival. On multivariate analysis, MeHPLAase activity proved t o be an independent factor for predicting a short period of recurrence -free survival.