Are All Triple-Negative Breast Cancers Created Equal?
Posted: Monday, June 28, 2021
According to research presented in JAMA Network Open, there may be an association between breast cancer histologic type and outcomes in survival and treatment among patients with triple-negative breast cancer. Zeina A. Nahleh, MD, of the Cleveland Clinic Florida, and colleagues found that patients with some histologic subtypes—such as metaplastic carcinoma—may be at increased risk for more aggressive disease and poorer prognosis versus other subtypes.
“Future research focusing on rare subtypes of breast cancer is desirable and could inform the optimal management of these relatively understudied carcinomas,” concluded the study authors.
The study included information from 8,479 patients (99.48% women) with triple-negative breast cancer, whose data were reported by the National Cancer Database between 2010 and 2016. Histologic subtypes represented in this cohort included metaplastic carcinoma (81%, n = 6,867), adenoid cystic carcinoma (16%, n = 1,357), and medullary carcinoma (3%, n = 255). The 5-year overall survival rate was highest for patients with medullary carcinoma (91.7%), followed by adenoid (88.4%) and metaplastic carcinomas (63.1%). Metaplastic carcinoma had a significantly higher 5-year mortality rate than did adenoid cystic carcinoma (36.91% vs. 8.33%).
Medullary carcinoma was found to make the earliest appearance, at a median patient age of 53 versus median ages of 62 and 63 for adenoid cystic and metaplastic carcinomas, respectively. Medullary carcinoma was also observed to have the lowest proportion of tumors with triple-negative immunohistochemistry at 22.4% (n = 57) versus 48.1% (n = 653) for adenoid cystic and 53.0% (n = 3,637) for metaplastic carcinomas. Furthermore, radiotherapy and chemotherapy were given more often for patients with medullary (radiotherapy, 61.1%; chemotherapy, 74.5%) and metaplastic (radiotherapy, 49.7%; chemotherapy, 68.6%) carcinomas than for patients with adenoid cystic carcinoma (radiotherapy, 52.4%; chemotherapy, 12.9%).
Disclosure: The study authors reported no conflicts of interest.