Dr. Patel on the Association Between Ki-67 and Race in Early Breast Cancer

Rima Patel, MD, chief Hematology/Oncology Fellow, Icahn School of Medicine, Mount Sinai, discusses the associations between the 21-gene oncotype DX recurrence score, Ki-67, and race in early-stage breast cancer.

In findings presented at the 2022 San Antonio Breast Cancer Symposium, investigators evaluated associations between the 21-gene Oncotype DX recurrence score, Ki-67, and race in patients with early-stage breast cancer, with data drawn from the National Cancer Database (NCDB). One of the things that were found that is consistent with prior studies is that patients who were Black and had hormone receptor (HR)–positive early breast cancer tended to be younger, Patel begins. These patients also tended to have larger and higher-grade tumors compared with other racial subgroups, Patel notes.

Moreover, investigators also found that Black patients had higher recurrence scores, which is consistent with data from the phase 3 TAILORx trial (NCT00310180), Patel continues. The randomized phase 3 trial aimed to evaluate the best individual therapy for women who have node-negative, estrogen receptor–positive breast cancer by using the Oncotype DX, as well as whether hormone therapy alone or in combination with chemotherapy was better for women who have an Oncotype DX recurrence score of 11 to 25.

In this retrospective study of patients from the NCDB, the main goal for investigators was to evaluate the relationship between Ki-67 and oncotype. Investigators found that in the overall population, the low Ki-67 population, and the intermediate Ki-67 population, there was only slight agreement between Ki-67 and recurrence; however, there was fair agreement in the high Ki-67 group. Furthermore, there was slight agreement in the White and Hispanic subgroups, but there was fair agreement in the Black and Asian-American/Pacific Islander subgroups, Patel explains.

Additionally, data showed that for high Ki-67 and high oncotype, the highest association was in the Black patient subgroup, Patel notes. This was attributed to the fact that this group had a higher proportion of patients with higher-grade tumors, higher Ki-67, and higher oncotype scores, Patel concludes.