Effects of aromatase inhibitors and body mass index on steroid hormone levels in women with early and advanced breast cancer. Issue 8 (31st March 2014)

• Record Type: Journal Article
• Authors: Elliott, K M; Dent, J; Stanczyk, F Z; Woodley, L; Coombes, R C; Purohit, A; Palmieri, C
• Is Part Of: British journal of surgery. Volume 101:Issue 8(2014:Aug.)
• Page Start: 939
• Page End: 948
• Publication Date: 2014-03-31
• Subjects: Surgery -- Periodicals; 617.005
• DOI: 10.1002/bjs.9477
• Languages: English
• ISSNs: 0007-1323

Abstract

Abstract: Background: Aromatase inhibitors (AIs) are central to the management of oestrogen receptor-positive breast cancer in the adjuvant and metastatic setting. Levels of circulating steroid hormones (SHs) were measured in patients established on AIs to investigate: the influence of body mass index (BMI) in both the adjuvant and metastatic setting; the class of AI utilized in the adjuvant setting (steroidal versus non-steroidal); and differences in SH levels between women treated adjuvantly and those receiving a second-line AI for locally advanced/metastatic disease. Methods: Plasma levels of androstenedione, 5-androstene-3β, 17β-diol, dehydroepiandrosterone, oestradiol and testosterone were measured by radioimmunoassay in women with breast cancer who were receiving AIs in either an adjuvant or a metastatic setting. Differences between mean SH levels by class of AI, BMI, and second-line versus adjuvant therapy were assessed. Results: Sixty-four women were receiving AI therapy, 45 (70 per cent) in an adjuvant setting and 19 (30 per cent) were taking a second-line AI. There was no significant correlation between BMI and SH levels. However, BMI was significantly higher in the second-line AI cohort compared with the adjuvant cohort (29·8 versus 26·2 kg/m 2 respectively; P = 0·026). In the adjuvant setting, patients receiving a steroidal AI had significantly higher levels of all five hormones ( P < 0·050). In the second-line AI cohort, oestradiol levels were significantly higher than in the adjuvant cohort (4·5 versus 3·3 pg/ml respectively; P = 0·022). Multivariable analysis adjusted for BMI confirmed the higher residual oestradiol level in the second-line AI group ( P = 0·063) and a significantly higher androstenedione level ( P = 0·022). Conclusion: Residual levels of SH were not significantly influenced by BMI. However, the significant differences in residual SH levels between the second-line and adjuvant AI cohort is of relevance in the context of resistance to AI therapy, and warrants further investigation. Abstract : Risk of attenuated aromatase inhibitor effect