Survival Outcomes for Patients With Clinical Complete Response After Neoadjuvant Chemotherapy: Is Omitting Surgery an Option?

Background Surgery after neoadjuvant chemotherapy (NCT) is an accepted treatment approach for locally advanced and some early-stage breast cancers, even for patients with a clinical complete response (cCR) after NCT. This study sought to evaluate the survival outcomes for patients with cCR to NCT who did not undergo surgery. Methods The National Cancer Data Base (NCDB) was used to identify 93,417 women age 18 years or older with a diagnosis of invasive breast cancer who received NCT between 2010 and 2015. The study identified 350 women with cT1-4, N0-3, and M0 tumors who underwent NCT and did not have surgery. A matched surgical cohort was extracted from the NCDB, and overall survival (OS) was compared between the surgical and nonsurgical patients after NCT. Results Of the 350 NCT patients who did not undergo surgery, 45 (12.9%) had cCR, 51 (14.6%) had a partial response, 241 (68.9%) had a response but whether complete or partial was not recorded, and 13 (3.7%) had no response/progression. The 5-year OS was better in the cCR group than in the no-cCR group (96.8% vs 69.8%; p = 0.004). A 5-year OS analysis of the cCR patients without surgery (n = 45; median follow-up period, 37 months) compared with the patients with a pathologic complete response who underwent surgery (n = 3938; median follow-up period, 43 months) showed no statistically significant difference (96.8% vs 92.5%, respectively; p = 0.15). Conclusion This retrospective cohort study demonstrated that active surveillance or de-escalation therapy may be an option for patients who achieve cCR. Prospective studies are underway to determine whether a subgroup of patients may forgo surgery in the setting of cCR after NCT.