Chemotherapy in HR-positive HER2-negative MBC

Longtermsurvivor

Yet another ASCO abstract. Healing regards, Stephanie

Real-world use of first-line chemotherapy in post-menopausal patients with HR-positive HER2-negative metastatic breast cancer (mBC) in a US community oncology network.

Sub-category:
ER+

Category:
Breast Cancer—HER2/ER

Meeting:
2016 ASCO Annual Meeting

Abstract No:
561

Poster Board Number:
Poster Session (Board #49)

Citation:
J Clin Oncol 34, 2016 (suppl; abstr 561)

Author(s): Debra A. Patt, Xiaolong Jiao, Eileen Fonseca, Jamyia Clark, Patricia S. Fox, Ruslan Horblyuk, Lynn McRoy, Jack Mardekian, Bhakti Arondekar; The US Oncology Network/McKesson Specialty Health, The Woodlands, TX; Pfizer Inc., New York, NY

Abstract Disclosures

Abstract:

Background: Endocrine therapy (ET) is recommended as 1^st line of therapy (LOT) for patients (pts) with HR+/HER2- mBC. Chemotherapy (CT), however, has also been used, though wide practice variation exists. The purpose of this study was to understand the utilization of 1^st line CT and its toxicities for HR+/HER2- mBC in a US community oncology setting.

Methods: A retrospective study was conducted using US Oncology's iKnowMed electronic health record database, supplemented with chart review. Post-menopausal women with a diagnosis of HR+/HER2- mBC between Jan. 2010 and Dec. 2013 who received CT as the 1^st therapy within 90 days after diagnosis were included. Pts were followed through Dec. 2014 or their last visit. CT regimens and toxicities were analyzed.

Results: Of the 8,953 post-menopausal mBC pts, 39.4% (n = 3,525) received at least one CT agent within 90 days after diagnosis. Among those, 598 pts met all inclusion criteria with a final sample of 150 pts, verified by chart review, for analysis. The majority of pts had recurrent mBC (62.7%). Median age was 63 years (range 41-86). In the 1^st line setting, the most common single agent CT regimens were paclitaxel (24.7%), nab-paclitiaxel (15.3%), and capecitabine (14.0%). The most common combination regimens of CT included cyclophosphamide, paclitaxel/nab-paclitaxel, and docetaxel-containing regimens (18.7%, 13.3%, 11.3%, respectively). Median duration of 1^st line CT was 3.9 months (range < 1 to 42.4). CT was discontinued in 69.3% of pts, and the main reasons for discontinuation, as noted by physician, were response achieved (38.7%), disease progression (29.3%), and toxicity (19.3%). The most common side effects included fatigue/malaise (87.0%), anemia (43.8%), neuropathy (43.8%), neutropenia/neutropenic fever (43.8%), nausea/vomiting (39.0%), abdominal pain (34.9%), and diarrhea (32.9%). 72.7% of pts received ET after CT.

Conclusions: Both single agent and combination CT were frequently used in the 1^st line setting for post-menopausal pts with HR+/HER2- mBC. CT toxicities were common and should be considered when planning individualized treatment.