1. Breast Cancer Res Treat. 2019 Aug;177(1):197-206. doi: 
10.1007/s10549-019-05290-0. Epub 2019 May 30.

Patterns of relapse after neoadjuvant chemotherapy in breast cancer: 
implications for surveillance in clinical practice.

Saw S(1), Lim J(2), Lim SH(3), Wong M(1), Lim C(2), Yap YS(4).

Author information:
(1)Division of Medical Oncology, National Cancer Centre Singapore, 11 Hospital 
Drive, Singapore, 169610, Singapore.
(2)Division of Clinical Trials and Epidemiological Sciences, National Cancer 
Centre Singapore, 11 Hospital Drive, Singapore, 169610, Singapore.
(3)Breast Department, KK Women's and Children's Hospital, Singapore, 100 Bukit 
Timah Road, Singapore, 229899, Singapore.
(4)Division of Medical Oncology, National Cancer Centre Singapore, 11 Hospital 
Drive, Singapore, 169610, Singapore. yap.yoon.sim@singhealth.com.sg.

PURPOSE: This study aimed to identify patterns of relapse after neoadjuvant 
chemotherapy (NAC) for breast cancer to refine follow-up recommendations.
METHODS: Retrospective analysis on 523 breast cancer patients treated with NAC 
at two public hospitals in Singapore between 2000 and 2014.
RESULTS: Majority of patients (71.9%) had locally advanced disease. Median 
follow-up was 55 months. 5-year recurrence rate was significantly higher in 
triple negative breast cancer (TNBC) than non-TNBC subtypes (38.4% vs. 29.5%; 
p = 0.042); 85% of recurrences involved distant sites. Among TNBC and HR 
(hormone receptor)-/HER2+ subtypes, 97.0% and 95.0% of relapses occurred within 
3 years from diagnosis respectively while 10.6% of relapses among HR+ subgroup 
occurred beyond 5 years. Recurrence risk in high-grade tumours decreased with 
time. Stage III at diagnosis (hazard ratio = 2.94; p < 0.001), grade 3 tumours 
(hazard ratio = 2.87; p = 0.018), not achieving pathologic complete response 
(pCR) (hazard ratio = 8.77; p = 0.003) and not receiving adjuvant radiotherapy 
(hazard ratio = 3.19; p < 0.001) were independent predictors of inferior 
recurrence-free survival. Serum CA 15-3 was raised in 49% of patients upon 
relapse; it correlated with inferior post-relapse survival (median 11 months vs. 
22 months; p = 0.019).
CONCLUSIONS: While more intensive follow-up during the first 3 years may be 
required for patients who do not achieve pCR, especially those with TNBC and 
HR-/HER2+ tumours, the benefit from blood tests such as CA 15-3 appears limited, 
and the benefit from intensification of surveillance remains to be addressed in 
prospective studies on high-risk patients.

DOI: 10.1007/s10549-019-05290-0
PMID: 31147984 [Indexed for MEDLINE]