Survival Trends and Patient Characteristics between 2004 and 2016 for Breast Cancer in Japan Based on the National Clinical Database-Breast Cancer Registry

Abstract This is a prognostic report by the Japanese Breast Cancer Society on breast cancer extracted from the National Clinical Database-Breast Cancer Registry of Japan. Here, we present a summary of 457,878 breast cancer cases registered between 2004 and 2016. The median follow-up duration was 5.6 years. The median age at the start of treatment was 59 years (5–95%: 38–82 years) and increased from 57 years between 2004 and 2008 to 60 years between 2013 and 2016. The proportion of patients with Stage 0-II disease increased from 74.5–78.3%. The number of cases with estrogen and progesterone receptor positivity increased from 74.8–77.9% and 60.5–68.1%, respectively. Regarding (neo-)adjuvant chemotherapy, the taxane or taxane-cyclophosphamide regimen (T/TC) increased by 2.4–8.2%, but the (fluorouracil (F)) anthracycline-C [(F)AC]-T/(F) epirubicin (E)C-T and (F)AC/(F)EC regimens decreased by 18.6–15.2% and 13.5–5.0%, respectively. Regarding (neo-)adjuvant anti-human epidermal growth factor-2 (HER2)-targeted therapy, the use of trastuzumab increased from 4.6–10.5%. The rate of sentinel lymph node biopsy increased from 37.1–60.7%, while that of axillary dissection decreased from 54.5–22.6%. Improvements in disease-free and overall survival were observed in patients with HER2-positive breast cancer, but there was no apparent trend in patients with hormone receptor-positive, HER2-negative, or triple-negative breast cancers.