A Prospective Pilot Study Investigating the Nature, the Onset and the Incidence of Joint Pain in Menopausal, Breast Cancer Patients Receiving Aromatase Inhibitor (AI) Therapy.
Authors: Robidoux A. , Rich E. , Bureau N. , Mader S. , Tremblay N. , Turgeon J. 
Published: December 2010

Abstract
Background: Joint symptoms have been commonly reported by patients using aromatase inhibitors (AIs). A survey of women who received AI therapy reported 47% of AI-joint related problems (Crew, JCO 2007;25:3877-83.) The exact etiology has not been identified. The purpose of this pilot prospective study was to determine the nature, the onset, and the incidence of AI musculosketelal syndromes (AIMS trial) as well as to correlate with ultrasound imaging, serum biochemistries and pain/depression assessment.Methods: Between 05/08 and 11/08, 30 women with hormone responsive invasive breast cancer initiated treatment with anastrazole 1mg daily during or following radiation therapy. Patients could have received postoperative chemotherapy but no prior hormonal therapy. Patients evaluations were performed at 48 hours after the initiation of treatment and at 1 week(w), 3w, 5w, 7w, 12w and 24w. Clinical examination by a rheumatologist, ultrasound imaging and serum biochemistries were performed at the same visit (C-Reactive Protein, Rheumatoid Factor, Antinuclear Antibody, Vitamin D, Estradiol (LC/LC/LC). Questionnaires were used to assess pain and depression (Brief Pain Inventory; Beck Depression Inventory).Results: After rheumatological examination, all 30 patients presented musculosqueletal conditions at baseline. Twenty out of 30 patients (66%) pain symptoms did not increase during AI administration. Five patients (16%) reported pain symptoms of moderate intensity at baseline, which were not exacerbated during AI administration. Only five other patients (16%) had an increase in pain symptoms that could be possibly related to AIs; four patients presented exacerbation of pain symptoms due to pre-existing osteoarthritic conditions and two patients developed new pain symptoms due a tenosynovial phenomenon (one patient presents these two patterns). No correlation was seen with any of the above serum biomarkers. All patients with pain symptoms were treated with NSAIDs and their pain symptoms rarely reached severe intensity. All patients were compliant as shown by estradiol levels measured by LC/LC/LC and none of the patients had to interrupt their treatment with anastrazole. Differences in gene expression in blood mononuclear cells isolated from patients from different groups are being investigated using microarray profiling.Conclusion: This study suggests that only 16% of the patients had and exacerbation of their pain symptoms or developed new pain symptoms in the upper limbs that could be possibly related to AI administration. The study also suggests that 1) it is important to evaluate the patient's pain prior to starting a treatment with AIs to avoid misinterpretation of pain causes and 2) pain symptoms should be treated in order to avoid their escalation which could lead to the unnecessary interruption of vital anticancer therapy. A larger prospective trial is underway.
Citation Information: Cancer Res 2009;69(24 Suppl):Abstract nr 4090.