In:
Journal of Clinical Oncology, American Society of Clinical Oncology (ASCO), Vol. 34, No. 3_suppl ( 2016-01-20), p. 158-158
Abstract:
158 Background: Tolerance of AI therapy can be poor due to treatment-emergent toxicities and can lead to early discontinuation (non-persistence). Patients often switch from one AI to another when toxicities develop; however, limited prospective data exist on patients who switch AI. Here we describe the effect of switching from E to L or L to E on tolerance of and persistence with therapy. Methods: Postmenopausal women initiating AI therapy were enrolled on the ELPh trial and randomized to E or L. Those that stopped their AI for self-reported intolerance were offered crossover to alternate AI after a 2-6 week washout. Kaplan-Meier estimates of proportions on AI after 1, 3, and 6 months were assessed during 1 st and 2 nd AI. Associations between time on 2 nd AI and clinicopathologic factors were analyzed using univariable Cox proportional hazards model. To evaluate effect of crossover on patient-reported outcomes, multiple questionnaires, including a pain visual analog scale (VAS), were assessed serially. Results: 83 women, mean age 60 years, 45% prior chemotherapy, and 31% with prior tamoxifen use, participated in the crossover protocol. 71% reported improvement in symptoms a mean 4.72 weeks after discontinuing 1 st AI therapy. Median time on 1 st AI was 6.8 months (95% CI 5.8-9 months), and on 2 nd AI was 11.5 months (6.9-24.2). The probability of persistence at 1, 3, and 6 months for the 1 st AI was 94%, 76%, and 55% and for the 2 nd AI was 89%, 73%, and 62%, respectively. There was no significant association between duration on 2 nd AI and 1 st AI (L vs. E), duration on 1 st AI, age, body mass index, or prior therapies. The change in pain VAS from baseline to 1 or 3 months was not significantly different during treatment with the 1 st or 2 nd AI. Conclusions: Although all AI medications have similar mechanisms of activity, nearly two-thirds of patients who are intolerant of one AI are able to maintain therapy for at least 6 months following switch to 2 nd AI. Switching is a reasonable approach for women who cannot tolerate 1 st AI that may improve persistence with therapy. The mechanisms for intrapatient variation in tolerance warrant further study. Clinical trial information: NCT00228956.
Type of Medium:
Online Resource
ISSN:
0732-183X
,
1527-7755
DOI:
10.1200/jco.2016.34.3_suppl.158
Language:
English
Publisher:
American Society of Clinical Oncology (ASCO)
Publication Date:
2016
detail.hit.zdb_id:
2005181-5
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