PLoS ONE (Jan 2020)

Prognostic value of the Residual Cancer Burden index according to breast cancer subtype: Validation on a cohort of BC patients treated by neoadjuvant chemotherapy.

  • Anne-Sophie Hamy,
  • Lauren Darrigues,
  • Enora Laas,
  • Diane De Croze,
  • Lucian Topciu,
  • Giang-Thanh Lam,
  • Clemence Evrevin,
  • Sonia Rozette,
  • Lucie Laot,
  • Florence Lerebours,
  • Jean-Yves Pierga,
  • Marie Osdoit,
  • Matthieu Faron,
  • Jean-Guillaume Feron,
  • Marick Laé,
  • Fabien Reyal

DOI
https://doi.org/10.1371/journal.pone.0234191
Journal volume & issue
Vol. 15, no. 6
p. e0234191

Abstract

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IntroductionThe Residual Cancer Burden (RCB) quantifies residual disease after neoadjuvant chemotherapy (NAC). Its predictive value has not been validated on large cohorts with long-term follow up. The objective of this work is to independently evaluate the prognostic value of the RCB index depending on BC subtypes (Luminal, HER2-positive and triple negative (TNBCs)).MethodsWe retrospectively evaluated the RCB index on surgical specimens from a cohort of T1-T3NxM0 BC patients treated with NAC between 2002 and 2012. We analyzed the association between RCB index and relapse-free survival (RFS), overall survival (OS) among the global population, after stratification by BC subtypes.Results717 patients were included (luminal BC (n = 222, 31%), TNBC (n = 319, 44.5%), HER2-positive (n = 176, 24.5%)). After a median follow-up of 99.9 months, RCB index was significantly associated with RFS. The RCB-0 patients displayed similar prognosis when compared to the RCB-I group, while patients from the RCB-II and RCB-III classes were at increased risk of relapse (RCB-II versus RCB-0: HR = 3.25 CI [2.1-5.1] pConclusionRCB index is a reliable prognostic score. RCB accurately identifies patients at a high risk of recurrence (RCB-III) with TNBC or HER2-positive BC who must be offered second-line adjuvant therapies.