Survey on postoperative drug therapy for hormone receptor-positive, HER2-negative patients

on 10月 21, 2024

Every October is Breast Cancer Month. Breast Cancer Month is an international health campaign that aims to promote screening and prevention of the disease, which affects 2.3 million women worldwide.

In the area of breast cancer, the Oncotype DX Breast Cancer Recurrence Score Program has been covered by insurance since September 2023, enabling a more accurate determination of recurrence risk and the selection of appropriate chemotherapy for patients with hormone receptor-positive/HER2-negative early-stage breast cancer.

In conjunction with Breast Cancer Month, Care-net and Macromill CareNet surveyed 52 physicians (28 at cancer treatment-based hospitals and 24 at non-cancer-treatment-based hospitals) among CareNet members who treat hormone receptor-positive/HER2-negative early-stage breast cancer patients.

<Survey period> 11/09/2024–25/09/2024

・94% of doctors had performed Oncotype DX in the last year, and 27% of patients with [HR-positive/HER2-negative early invasive breast cancer] had received postoperative drug therapy.

・In terms of first-line drugs for postoperative drug therapy by risk of recurrence, chemotherapy accounted for 80% of all patient types in patients at “high risk,” hormonal therapy for 70%–90% of patients with [lymph node-negative (low to intermediate risk)], and chemotherapy for approximately 70% of [lymph node-positive (low to intermediate risk)]. The proportion of patients with positive lymph node metastases (low-to-medium risk) ranged from 70% to 90%.

・The most common benefit of Oncotype DX was “can determine which patients do not need postoperative chemotherapy” at 88%, followed by “can identify patients who can benefit from chemotherapy” at 54% and “can predict the risk of distant recurrence” at 42%. “Can identify patients who will benefit from chemotherapy” was higher among low users, while “Can predict the risk of distant recurrence” was higher among high users, with high users tending to perform the test on a wider range of patients to predict the risk of recurrence and low users tending to perform it on patients who appeared to be clinically at higher risk and to confirm the need for chemotherapy.

・In the future, the intention to perform Oncotype DX will increase (Top2 box) with around 40% of physicians in the “lymph node-negative/(premenopausal and postmenopausal)” and “lymph node-positive/premenopausal” categories, and 60% in the “lymph node-positive/postmenopausal” category. This is expected to result in more patient-oriented treatment options.

RESULT

Oncotype DX was performed by 94% of physicians in the last year and on 27% of patients with [HR-positive/HER2-negative early invasive breast cancer] who underwent postoperative pharmacological treatment.

The “lymph node-positive/postmenopausal” status was the most common (34%), followed by “lymph node-positive/premenopausal” (28%), “lymph node-negative/premenopausal” (24%), and “lymph node-negative/postmenopausal” (18%).

Percentage of patients with Oncotype DX performed

“In the last 12 months, please indicate which genetic tests you have performed on breast cancer patients.” The BRCA gene test was the most common test (96%), and tests other than the BRCA gene test were performed by less than 10% of the respondents, regardless of their institution.

Genetic tests carried out in the last 12 months

“Please inform us about the first choice of postoperative drug therapy for patients with [HR-positive/HER2-negative early invasive breast cancer], according to the risk of recurrence.” In the question “What is your first choice of postoperative drug treatment for patients with [HR-positive/HER2-negative early-stage invasive breast cancer] by risk of recurrence?,” chemotherapy accounted for 80% of all patient types among “high-risk” patients, hormone therapy for 70%–90% in “lymph node-negative (low to intermediate risk)” patients, and chemotherapy for approximately 70% in “lymph node-positive (low to intermediate risk)” patients. Looking at differences by percentage of Oncotype DX performed, high users were slightly more likely to choose “chemotherapy” in the “premenopausal (medium risk)” and “postmenopausal (low to medium risk)” categories of “lymph node-negative.”

First choice for postoperative drug treatment

When asked in an open-ended question about the reasons for not performing Oncotype DX on patients with [HR-positive/HER2-negative early invasive breast cancer], 29% of doctors gave the reason as “used according to patient type,” while the answers “can clinically determine low grade” (12%) and “premenopausal lymph nodes metastasis-positive” (8%) suggested that in some cases the need for testing is determined by clinical judgement. In other cases, 17% of the physicians stated that “the patient does not wish to be tested,” indicating that the patient’s financial status also influenced the decision to perform the test.

Reasons why some patients do not implement Oncotype DX

“Please tell us about the perceived benefits of performing Oncotype DX in patients with [HR-positive/HER2-negative early-stage invasive breast cancer].” The most common response was “Can determine which patients do not need postoperative chemotherapy” at 88%, followed by “Can identify patients who can benefit from chemotherapy” at 54% and “Can predict the risk of distant recurrence” at 42%.

Looking at differences by percentage of Oncotype DX implementation, both high and low users had a high percentage of responses in common for “can determine which patients do not need postoperative chemotherapy,” but low users had a higher percentage of responses for “can identify patients who can benefit from chemotherapy” at 68%, while high users had a higher response rate for “can predict the risk of distant recurrence” at 52%. This suggests that high users tend to perform the test on a wider range of patients to predict the risk of recurrence, whereas low users tend to perform it on patients who appear to be clinically at a higher risk to confirm the need for chemotherapy.

Advantages of Oncotype DX

“Please inform us about your intention to implement Oncotype DX in the future for patients with [HR-positive/HER2-negative early-stage invasive breast cancer].” About 40% of doctors answered “will increase (Top2 box)” for “lymph node-negative/(pre/postmenopausal)” and “lymph node-positive/premenopausal,” while 60% thought it would increase for “lymph node-positive/postmenopausal.” Both high and low users had a high willingness to implement the treatment, but especially high users had a high willingness to implement it for lymph node-positive/postmenopausal patients, which is expected to promote the selection of a more suitable treatment for the patient.

Intention to implement Oncotype DX in the future