A new study has reported on differences in locoregional recurrence (recurrence in the breast, chest wall, or lymph nodes) according to hormone receptor status among stage II-III breast cancer patients treated with chemotherapy, mastectomy, and radiation. To conduct the study, the authors examined the medical records of 582 consecutively treated patients between 1999 and 2009. The women were followed for a median of 44.7 months. Of the women with HER2 positive disease, 86% received treatment with Herceptin (trastuzumab).

Among study participants as a whole, five-year progression-free survival was estimated to be 73.9% and five-year overall survival was 84%. The cumulative five-year incidence of locoregional recurrence as first site of recurrence (i.e., not distant metastasis) was 6.2%. The cumulative incidence of locoregional recurrence was 8.6% for estrogen receptor negative (ER-) tumors compared to 4.4% for ER positive (ER+) disease. The cumulative incidence of locoregional recurrence was 8.5% compared to 3.4% for progesterone receptor negative (PR-) compared to PR positive (PR+) disease. The cumulative incidence of locoregional recurrence was 1.7% compared to 7.5% for HER2 positive compared to HER2 negative disease.

The five-year cumulative incidence of locoregional recurrence was 11.8% for triple negative disease (ER-/PR-/HER2-) compared to 3.9% for all other receptor combinations. Among women with ER+ tumors, the five-year locoregional recurrence rate 7.8% for ER+/PR- tumors compared to 3.4% for ER+/PR+ disease. The authors conclude that tumors that are HER2 overexpressing and treated with Herceptin have a very low rate of locoregional recurrence. On the other hand, ER-, PR-, and triple negative tumors have increased risk of locoregional recurrence.

Please see our articles on ER+/PR+, mixed hormone receptor, HER2 positive and triple negative breast cancer prognosis for more information on prognosis by breast cancer subtype.