Zekan, Patricia J.

Abstract Current therapies for breast cancer prevention only prevent estrogen receptor positive (ER+) disease and toxicity limits use of these agents. Vitamin D is a potential prevention therapy for both ER+ and ER− disease and is safe with few side effects. This study evaluates the effect of 1-year of vitamin D supplementation on mammographic density (MD), a biomarker of breast cancer risk in a multicenter randomized controlled trial. Premenopausal women with ≥25% MD and no history of cancer were randomly assigned to 2,000 international units (IU) of vitamin D or placebo orally daily for 1 year. Change in percent MD was evaluated using Cumulus software after all participants completed treatment. Three hundred women enrolled between January 2011 and December 2013 with a mean age of 43 and diverse ethnicity [14% Hispanic, 12% African American (AA)]. Supplementation significantly increased vitamin D levels compared with placebo (14.5 ng/mL vs. −1.6 ng/mL; P < 0.0001) with all participants on the vitamin D arm achieving vitamin D sufficiency at 12 months. Vitamin D was safe and well tolerated. After adjustment for baseline MD, the mean between-arm difference (vitamin D vs. placebo) at 1 year was −0.75 (−0.26, 1.76; P = 0.56). A greater effect was seen for women with ≥50% MD and AA women, although neither reached significance. This randomized controlled trial demonstrated significant improvement in vitamin D levels with 2,000 IU for 1 year, with 100% of supplemented women achieving sufficiency. However, a null effect was seen regarding change in MD for premenopausal women (the primary outcome of the study). Prevention Relevance: Current therapies for breast cancer prevention only prevent estrogen receptor positive (ER+) disease and are underutilized due to toxicity and side effects. Vitamin D is a potential prevention therapy for both ER+ and ER− disease and is safe with few side effects.

Abstract This abstract was withdrawn by the authors.

220 Background: Paclitaxel is associated with both an acute pain syndrome (P-APS) and chronic chemotherapy-induced peripheral neuropathy (CIPN). Preliminary animal data suggest that minocycline may be effective for the prevention of chemotherapy-induced neurotoxicity. The purpose of this pilot study was to investigate the efficacy of minocycline for the prevention of CIPN and P-APS. Methods: Patients with breast cancer were enrolled prior to initiating neoadjuvant or adjuvant weekly paclitaxel for 12 weeks. They were randomized to receive minocycline 200mg on day 1 followed by 100mg twice daily or a placebo, with the same dosing schedule. Patients completed (1) an acute pain syndrome questionnaire daily during chemotherapy, and (2) the EORTC QLQ-CIPN20 questionnaire at baseline, prior to each dose of paclitaxel, and monthly for 6 months post treatment. The primary goal was to obtain pilot data regarding the possible effect of minocycline on the prevention of paclitaxel-induced CIPN and P-APS, to determine if conducting a larger phase III placebo-controlled trial was indicated. Scores obtained from patient questionnaires were converted to a 0-100 scale, where higher scores = better quality of life. Results: Forty-seven patients were randomized, 45 of which were evaluable, with a mean age of 55. There were no remarkable differences noted between the two groups for the overall sensory score of the EORTC-CIPN 20 or its individual sub-questions, which evaluated tingling, numbness, or shooting burning pain in hands and feet. However, there was a significant difference in the daily average AUC pain score attributed to P-APS, favoring minocycline (median 96.0 vs 84.3; p = 0.02). Correspondingly, patients receiving minocycline used less opioid pain medications for control of P-APS (0% vs 23%, P = 0.05). Not only were no increased toxicities reported with minocycline, but there was an apparent improvement in fatigue (median AUC 76.7 vs 59.0; P = 0.02). Conclusions: Based on the results of this pilot study, minocycline did not appear to be beneficial for the prevention of CIPN, but did look promising for reducing P-APS. Further study of this effect may be warranted. Clinical trial information: NCT02297412.