Local radiotherapy alone following neoadjuvant chemotherapy and surgery in combined clinical stage II and III breast cancer

Abstract

Purpose: The outcomes and recurrence patterns for patients with combined clinical stage II and III breast cancer treated with local but not regional radiotherapy after neoadjuvant chemotherapy (NAC) and surgery are poorly documented. Methods: We performed a retrospective review of a prospectively collected database comprised of breast cancer patients who received NAC at our institution. 172 patients met the specified criteria of receiving NAC, surgery inclusive of axillary nodal dissection and post-operative local (but not regional) radiotherapy. Results: One hundred eleven patients (64.5 %) were of combined clinical stage II and 61 (35.5 %) stage III at diagnosis. 103 patients (59.9 %) were clinically node positive with 101 cN1. On post-NAC pathology 29 (16.9 %) patients had a complete response, 30 (17.6 %) were combined yp stage I, 104 (60.5 %) yp stage II and 9 (5.2 %) yp stage III. 77 (44.8 %) were node positive on post-NAC pathology, all ypN1. 52.3 % were treated with breast conservation. At a median follow up of 67 months, 56 patients experienced breast cancer recurrence and 47 had died with breast cancer the dominant cause. Actuarial 5 and 10 year estimated freedom from locoregional recurrence (FFLRR), freedom from distant metastases (FFDM), disease free (DFS) and overall survival (OS) were 90 and 83.5, 74.5 and 64, 69.5 and 56, 79.5 and 65 % respectively. The most common pattern of failure was distant alone (without local or regional failure). Regional failure as the only site of first failure occurred in just three patients but was a component of first failure in a further twelve. Predictive factors on multivariate analysis for FFLRR were clinical stage II and estrogen receptor positivity. Prognostic factors were ypN0 stage and estrogen receptor positive status. Conclusions: Local radiotherapy alone may be reasonable for selected patients. Isolated distant recurrence is the dominant mode of failure for breast cancer patients who have received local radiotherapy without regional coverage following NAC.