Treatment And Outcomes Of Female Patients Who Underwent Mastectomy For Breast Cancer At Yale New Haven Hospital From 2000-2005: Examination Of Recurrence Rates

Introduction: Locoregional recurrence (LRR) and distant recurrence after mastectomy are very important clinical endpoints. It is well established that postmastectomy radiation therapy (PMRT) plays an important role in the treatment of locally advanced breast cancer and in the prevention of locoregional and distant recurrence. There are also other prognostic factors such as nodal status, tumor size, and predictive factors such as hormone receptor status that are known to influence local and distant recurrence. There are varying reports on the rates of LRR after mastectomy. This variation in published rates of LRR creates a limitation in adequately assessing risk and benefits of PMRT to reduce local and distant recurrence. Given the availability of more effective chemotherapy/systemic regimens, safer methods of delivering PMRT, there is a need to further evaluate the actual rates of locoregional and systemic recurrence after mastectomy. Aim: Our study sought to evaluate the local and distant recurrence rates in our population of patients who underwent mastectomy for breast cancer as well as the effects of various predictive and prognostic factors on local and distant recurrence. We hypothesized that the rate of local and distant recurrence in our patient population will be much lower than that stated in the published large-scale trials. Methods: All cases of breast cancer treated with mastectomy with or without post mastectomy radiation between Jan 1, 2000 and December 31, 2004, at Yale New Haven Hospital were analyzed. Results: A total of 443 cases were analyzed. Of the 356 cases in which local and distant recurrence status were known, 65 were non-invasive breast cancers while 291 were invasive breast cancer and invasiveness was unknown in 2 cases. Patients were followed for a mean of 79.6 months (std: 29.9). Local recurrence occurred in 2(3%) of non-invasive cancers and 5(1.7%) of invasive cancers. Distant recurrence occurred in none of the non-invasive cancers and 32(11%) of the invasive cancers. There were significant differences in distant recurrence by T stage (p=0.016), N stage (p=0.022), ER status ( p\u3c0.001) , PR status( p\u3c0.001), molecular type ( p\u3c0.001) and PMRT (p=0.01). However on multivariate analysis, only differences in nodal status (p=0.02) and ER status( p\u3c0.001) remained significant for distant recurrence. Conclusion: Our study found lower than expected rates of local and distant recurrence