Abstract 2471
Background
Patients with early breast cancer (EBC) achieving pathologic complete response (pCR) after neoadjuvant chemotherapy (NACT) have a favorable prognosis. Breast surgery and more chemotherapy treatment might be avoided in patients in whom the presence of residual tumor can be ruled out with high confidence. We investigated the diagnostic accuracy of contrast enhanced MRI (CE-MRI) in predicting pCR and long-term outcome after NACT.
Methods
Patients with EBC, who had undergone CE-MRI before and after NACT, were retrospectively analyzed (n = 421), and regarding to the absence (radiologic complete remission; rCR) or presence (no-rCR) of residual contrast enhancement.
Results
Overall rCR and pCR rates were 35% (147/421) and 36% (154/421), respectively. We found a total of 70% (101/144) of rCR corresponded to a pCR (meaning the positive predictive value - PPV). In contrast, in 80% (219/272) of patients, residual tumor observed on MRI was pathologically confirmed (meaning the negative predictive value - NPV). Sensitivity to detect a pCR was 65% (101/154), while specificity to detect residual tumor and accuracy were 83% (219/262); and 76% (320/421), respectively. The PPV was significantly lower in luminal compared to HER2 positive and triple negative tumors (10/34 = 29 % vs. 50/62 = 81% and 41/48 = 85% respectively). The concordance between rCR and pCR was moderate (Cohen’s kappa − 0.5) but with low level in luminal tumors (Coheńs Kappa – 0.3). In multivariate analysis both assessments were significantly associated with disease free survival (rCR : HR:0,344 P = 0.001; pCR : HR : 0,154 P = 0.000), but not in luminal tumors (rCR : HR:0,813 P = 0.692; pCR : HR : 0,326 P = 0.275).
Conclusions
The accuracy of preoperative CE-MRI to predict pCR after NACT for EBC is moderate but in luminal tumors did not accurately predict pCR. However, rCR was strongly associated with favorable RFS, especially in HER2 positive and triple negative breast cancer tumors.
Clinical trial identification
Editorial acknowledgement
Legal entity responsible for the study
The authors.
Funding
Has not received any funding.
Disclosure
All authors have declared no conflicts of interest.
Resources from the same session
4022 - Ribociclib (RIB) plus letrozole (LET) in male patients (pts) with hormone receptor-positive (HR+), human epidermal growth factor receptor-2–negative (HER2–) advanced breast cancer (ABC) from the CompLEEment-1 trial
Presenter: Mario Campone
Session: Poster Display session 2
Resources:
Abstract
3599 - Comparative effectiveness of palbociclib plus letrozole vs letrozole for metastatic breast cancer in US real-world clinical practices
Presenter: Rachel Layman
Session: Poster Display session 2
Resources:
Abstract
901 - Pharmacokinetics (PK), safety, and efficacy of [fam-] trastuzumab deruxtecan with OATP1B/CYP3A inhibitors in subjects with HER2-expressing advanced solid tumors
Presenter: Yung-Jue Bang
Session: Poster Display session 2
Resources:
Abstract
2777 - A Phase 2 study of abemaciclib in patients (pts) with brain metastases (BM) secondary to non-small cell lung cancer (NSCLC) or melanoma (MEL).
Presenter: Solmaz Sahebjam
Session: Poster Display session 2
Resources:
Abstract
3980 - Ribociclib (RIB) + letrozole (LET) in patients (pts) with visceral metastases (VM) or bone-only metastases (BOM) in hormone receptor-positive (HR+), human epidermal growth factor receptor-2–negative (HER2–) advanced breast cancer (ABC): Subgroup analysis from the CompLEEment-1 trial
Presenter: Michelino De Laurentiis
Session: Poster Display session 2
Resources:
Abstract
4024 - Ribociclib (RIB) + letrozole (LET) in patients (pts) with hormone receptor-positive (HR+), human epidermal growth factor receptor-2–negative (HER2–) advanced breast cancer (ABC) and central nervous system (CNS) metastases: Subgroup analysis from the phase 3b CompLEEment-1 trial
Presenter: Paul Cottu
Session: Poster Display session 2
Resources:
Abstract
2151 - Clinical outcome and toxicity data in patients with advanced breast cancer treated with cyclin-dependent kinase 4/6 (CDK4/6) inhibitors combined with endocrine therapy in a real-world clinical setting.
Presenter: Elena Fountzilas
Session: Poster Display session 2
Resources:
Abstract
3994 - Safety and efficacy of Ribociclib (RIBO) + letrozole (LET) in patients (pts) with hormone receptor-positive (HR+), human epidermal growth factor receptor 2-negative (HER2–) advanced breast cancer (ABC): Interim results from the Italian cohort of the CompLEEment-1 (C-1) study.
Presenter: Michele De Laurentiis
Session: Poster Display session 2
Resources:
Abstract
1370 - Interim Results From CompLEEment-1 (A Phase 3b Study of Ribociclib and Letrozole as First-Line Therapy for Advanced Breast Cancer in an Expanded Population): Spanish cohort results
Presenter: Javier Salvador
Session: Poster Display session 2
Resources:
Abstract
1109 - First Canadian Interim Analysis from the Phase IIIb CompLEEment-1 Ribociclib + Letrozole HR+ HER2- Advanced Breast Cancer Trial
Presenter: Cristiano Ferrario
Session: Poster Display session 2
Resources:
Abstract