番茄社区

SAN ANTONIO – Women with early triple-negative breast cancer did not appear to benefit from treatment with capecitabine (Xeloda) after surgery and standard anthracycline and/or taxane-containing chemotherapy given in either the neoadjuvant or adjuvant setting, researchers reported here.

After 5 years, the disease-free survival (DFS) for women on capecitabine after chemotherapy was 79.6% versus 76.8% among patients who were observed and not given adjuvant treatment (P=0.136), according to Miguel Martin, MD, of the Instituto de Investigacion Sanitaria Gregorio Maranon, Universidad Complutense de Madrid, and colleagues.

Overall survival (OS) was 86.2% in the investigational arm and 85.9% in the observation arm (P=0.623), they noted in a presentation at the San Antonio Breast Cancer Symposium (SABCS).

"This study failed to show a statistically significant increase in disease-free survival by adding capecitabine to standard neoadjuvant/adjuvant chemotherapy in early triple-negative breast cancer," Martin said at a press conference.

However, in women with non-basal like phenotype, capecitabine did offer some advantage, with a 5-year DFS rate of 82.6% versus 72.9% among women with other phenotypes (P=0.02), the authors reported. OS was better in this subtype as well, with 5-year survival of 89.5% for women with the non-basal phenotype versus 76.6% of women with other cancer phenotypes (P=0.007).

"All triple-negative breast cancer patients are treated in the same way," he said. "This is a mistake. We need to select the right drugs for the right patients."

"We need trials to try to identify the optimal chemotherapy for different types of breast cancer," he said, but pointed out that there is a lack of funding for trials to differentiate basal from non-basal phenotypes of breast cancer.

Matthew Goetz, MD, of the Mayo School of Medicine in Rochester, Minnesota, told 番茄社区 that the benefit in non-basal triple-negative breast cancer fit in with other studies involving capecitabine.

He noted that the study was conducted before results from the were presented at the 2015 SABCS. "If we have data from two different datasets -- CREATE X and Dr. Martin's study here -- I think that will move us towards potentially individualizing capecitabine in triple-negative breast cancer," said Goetz, who was not involved in the study.

Martin's group enrolled 876 women (448 to capecitabine; 428 to observation) from eight countries, and recruitment was completed in September 2011.

To be eligible for the study, a central laboratory had to identify the women as having early disease and being ER-negative, PR-negative, and HER2-receptor negative.

They had to have received six to eight cycles of standard anthracycline and/or taxane-containing chemotherapy, or four cycles of doxorubicin-cyclophosphamide (for node-negative disease) in the neoadjuvant or adjuvant setting. In addition, they had to have negative margins after surgery.

The median patient age was 49, and well over half were were postmenopausal, while 55.5% were lymph node negative and 71.7% had a basal phenotype. Nearly 68% received chemotherapy based on anthracyclines and taxanes.

Patients were randomized to either eight cycles of capecitabine (1,000 mg/m² bid, days 1-14, every 3 weeks) or observation. Median follow-up was 7.3 years.

Grade ≥3 adverse events (AEs) were observed in 40.4% of patients in the study arm and in 9.6% of patients, the AEs were related to capecitabine, with grade 3 hand-foot syndrome the most common AE (18.8% of patients).

"It is an important message that triple-negative breast cancer is really a very heterogeneous group of cancers, and we all need some education about this," said SABCS press conference moderator Carlos Arteaga, MD, of the Harold C. Simmons Comprehensive Cancer Center at the University of Texas Southwestern Medical Center in Dallas.

Arteaga said that when doctors are asked to determine the type of cancer, they just designate it as triple negative and do not differentiate between basal and non-basal.

"We all need to be educated ... we have a need for research," he added. "We have a duty to define their disease better."

Comment