Stromal Tumor-Infiltrating Lymphocytes: Prognostic Indicator in Triple-Negative Breast Cancer?
Posted: Wednesday, November 27, 2019
According to research presented at the European Society for Medical Oncology (ESMO) Congress 2019 (Abstract 175O) and published in the Annals of Oncology, a high percentage of stromal tumor-infiltrating lymphocytes may be a strong indicator of favorable prognosis in patients with stage I triple-negative breast cancer. “Stromal tumor-infiltrating lymphocytes provide important prognostic information in systemically untreated early-stage triple-negative breast cancer patients,” concluded Ji Hyun Park, MD, of the University of Ulsan College of Medicine in Seoul, and colleagues. “They may be used to identify stage I triple-negative breast cancer patients with excellent prognosis in whom chemotherapy may be withheld.”
The study included data collected from 528 patients with triple-negative breast cancer who had not undergone chemotherapy, 83% of whom had node-negative disease. Among all patients, the median level of stromal tumor-infiltrating lymphocytes was 10%, with an association between higher levels (P < 10-3) and a higher tumor grade. Grade 3 tumors were present in 50% of patients, whereas grade 1 tumors were found in 12% and grade 2 tumors were found in 38%. The overall median tumor size was 1.6 cm.
During follow-up, the endpoints of invasive disease–free, distant disease–free, and overall survival were analyzed. The presence of varying levels of stromal tumor-infiltrating lymphocytes were meaningful prognostic tools for all three endpoints. According to investigators, “Each 10% increment in stromal tumor-infiltrating lymphocytes corresponded to a hazard ratio of 0.90 (95% confidence interval [CI] = 0.82–0.97) for invasive disease–free survival, 0.86 (95% CI = 0.77–0.95) for distant disease–free survival, and 0.88 (95% CI = 0.79–0.98) for overall survival. In patients with stage I tumors with stromal tumor-infiltrating lymphocytes of at least 30% (n = 74), 5-year invasive disease–free survival was 91% (95% CI = 84%–98%), distant disease–free survival was 97% (95% CI = 93%–100%), and overall survival was 98% (95% CI = 95%–100%).
Disclosure: For full disclosures of study authors, visit academic.oup.com.