Prognostic value of response evaluation based on breast MRI after neoadjuvant treatment: a retrospective cohort study

Almir G V Bitencourt; Barbara S Pires; Vinicius F Calsavara; Erika M S Negrão; Juliana A Souza; Luciana Graziano; Camila S Guatelli; Fabiana B Makdissi; Solange M Sanches; Monique C Tavares; Cynthia A B T Osório; Marina De Brot; Elvira F Marques; Rubens Chojniak

doi:10.1007/s00330-021-08042-1

Prognostic value of response evaluation based on breast MRI after neoadjuvant treatment: a retrospective cohort study

Eur Radiol. 2021 Dec;31(12):9520-9528. doi: 10.1007/s00330-021-08042-1. Epub 2021 May 25.

Authors

Affiliations

¹ Department of Imaging, A.C.Camargo Cancer Center, São Paulo, Brazil. almir.bitencourt@accamargo.org.br.
² Anhembi-Morumbi University, São Paulo, Brazil.
³ Department of Epidemiology and Statistics, A.C.Camargo Cancer Center, São Paulo, Brazil.
⁴ Prevention Institute, Hospital de Amor de Barretos, Campinas, Brazil.
⁵ Department of Imaging, A.C.Camargo Cancer Center, São Paulo, Brazil.
⁶ Department of Breast Surgery, A.C.Camargo Cancer Center, São Paulo, Brazil.
⁷ Department of Clinical Oncology, A.C.Camargo Cancer Center, São Paulo, Brazil.
⁸ Department of Pathology , A.C.Camargo Cancer Center , São Paulo, Brazil.

PMID: 34036420
DOI: 10.1007/s00330-021-08042-1

Abstract

Objective: To investigate the impact of response evaluation after neoadjuvant chemotherapy (NAC) in breast cancer patients, assessed by both magnetic resonance imaging (MRI) and pathology, on disease-free survival (DFS).

Methods: This single-center, retrospective cohort study included consecutive breast cancer patients who underwent NAC and preoperative breast MRI. Resolution of invasive carcinoma in the breast and axilla was defined as complete pathological response (pCR). Radiological complete response (rCR) was defined as the absence of abnormal enhancement in the tumor site. Kaplan-Meier estimator was used to estimate the disease-free survival on 60 months. Cox regression analysis was used to estimate hazard ratio (HR) values.

Results: In total, 317 patients were included with a mean age of 47.3 years and a mean tumor size of 39.8 mm. The most common immunophenotype was luminal (44.9%), followed by triple-negative (26.8%). Overall, 126 patients (39.7%) had an rCR, while 119 (37.5%) had pCR; the radiological and pathological responses agreed in 252 cases (79.5%). During follow-up, patients who had rCR and pCR had a better DFS curve compared to patients with non-rCR and non-pCR, while those who had rCR or pCR presented an intermediate curve (Log-rank p = 0.003). Multivariate analysis showed a higher risk of recurrence in patients with non-rCR and non-pCR (HR: 5,626; p = 0.020) and those who had a complete response on MRI or pathology only (HR: 4,369; p = 0.067), when compared to patients with rCR and pCR.

Conclusions: The association of MRI and pathological responses after NAC might better stratify the risk of recurrence and prognosis in breast cancer patients.

Key points: • Association of response evaluation after neoadjuvant chemotherapy by pathology and MRI allows better stratification of prognosis. • Complete response to neoadjuvant chemotherapy on pathology and MRI was related to better disease-free survival. • Complete response on MRI or pathology only had a greater risk of recurrence.

Keywords: Breast neoplasms; Magnetic resonance imaging; Neoadjuvant therapy.

MeSH terms

Antineoplastic Combined Chemotherapy Protocols
Breast Neoplasms* / diagnostic imaging
Breast Neoplasms* / drug therapy
Chemotherapy, Adjuvant
Female
Humans
Magnetic Resonance Imaging
Middle Aged
Neoadjuvant Therapy*
Neoplasm Recurrence, Local / diagnostic imaging
Prognosis
Retrospective Studies
Treatment Outcome