The characteristics of malignant breast tumors in hormone replacement therapy users versus nonusers

The purpose of this study was to investigate the characteristics of breast cancer in hormone replacement therapy (HRT) users vs. nonusers.

We investigated the characteristics of all patients between the ages of 50 and 75 years with breast tumors. Then, an age-adjusted group of 55 nonusers was chosen to match and compare with HRT users.

Of the 243 patients available for evaluation, 55 (22.6%) used HRT. Disease stages in HRT users vs. nonusers were as follows: ductal carcinoma in situ (DCIS), 20% and 17.1%; stage I, 45.5% and 41.7%; stage II, 30.9% and 26.2%; stage III, 3.6% and 13.4%; and stage IV, 0% and 1.6% (P =.27). In the age-adjusted cohort, stages in nonusers were as follows: DCIS, 7.3%; stage I, 47.3%; stage II, 25.5%; stage III, 20%; and stage IV, 0% (P =.03). Tumor grades in HRT users vs. nonusers were as follows: grade I, 30.4% and 15.7%; grade II, 52.2% and 52.2%; and grade III, 17.4% and 32.1% (P =.035). Grades in cohort nonusers were as follows: I, 13.2%; II, 52.8%; and III, 34% (P =.05). In the invasive tumors, the positive estrogen receptor (ER) rates were 81.6% and 85.7% (P =.89); positive progesterone receptor (PR) rates were 53.1% and 54% (P =.95); and Her 2-neu positive rates were 18.4% and 17.6% (P =.95), respectively. No significant difference was found in intratumor DCIS, vascular invasion, and Ki-67 (P =.14,.9, and.79, respectively). The rate of lobular and favorable histological types was higher in the HRT user group: 26.6% vs. 15%.

Breast tumors in HRT users vs. nonusers were of a significantly lower stage and grade and accounted for a higher number of favorable histological types, but all other parameters were similar in the two groups.