Original Research
Metaplastic breast cancer: Treatment and prognosis by molecular subtype

https://doi.org/10.1016/j.tranon.2021.101054Get rights and content
Under a Creative Commons license
open access

Highlights

  • The role of radiotherapy (RT) in prognosis of metaplastic breast cancer remains controversial.

  • The effect of molecular subtype on treatment and prognosis is unclear.

  • Our study took the variables with difference in multivariate model into adjusted kaplan–Meier analysis.

  • Adjusted model showed that triple-negative but not HER2-positive or HR-positive patients receiving RT had a superior prognosis .

Abstract

Background

Metaplastic breast cancer (MBC) is a rare and aggressive subtype of breast. However, the effect of molecular subtype on treatment and prognosis of MBC remains unclear.

Patients and methods

The Surveillance, Epidemiology, and End Results database was used to analyze patients with MBC between 2010 and 2016. Molecular subtype was stratified to TN group (ER and PR-/HER2-), HER2 group (ER and PR-/HER2+, ER/PR+ and HER2+), and HR group (ER/PR+ and HER2-). The breast cancer-specific survival (BCSS) differences were estimated using multivariate Cox regression model and Kaplan-Meier curves.

Results

We included 1665 patients with median follow-up time of 27 months (range 0–83 months). 1154 (69.3%), 65 (3.9%), and 446 (26.8%) patients presented in TN group, HER2 group, and HR group, respectively. On multivariate Cox analysis, the prognosis was related to age, tumor size, regional node metastasis, and surgery. Molecular subtype remained no impact on BCSS. Radiotherapy (RT) was associated with better prognosis. Patients cannot benefit from chemotherapy. In Kaplan-Meier curve, triple-negative (P = 0.047) and HR-positive (P = 0.006) patients receiving RT had a superior BCSS than that not RT. HER2-positive patients cannot benefit from RT. However, adjusted Kaplan-Meier survival model showed that triple-negative (P = 0.019) but not HER2-positive (P = 0.575) or HR-positive (P = 0.574) patients receiving RT had a superior BCSS than that not RT.

Conclusions

Molecular subtype is not associated with the better prognosis of MBC. Patients could benefit from RT. However, triple-negative but not HR-positive or HER2-positive patients have superior survival after receiving RT.

Keywords

Metaplastic breast cancer
Adjusted Kaplan-Meier
Radiotherapy
Prognosis

Cited by (0)

1

Dr. Hu and Zhang contributed equally to this work.