Abstract PO1-11-06: Evaluating Symptom Clusters in Patients with Breast Cancer Experiencing Aromatase Inhibitor-Associated Musculoskeletal Symptoms
Authors: Nicole Fleege , Henry N. Lynn 
Published: May 2024

Abstract
Background: Although treatment with an aromatase inhibitor (AI) for 5-10 years decreases 10-year breast cancer mortality by about 40%, up to 25% of patients will stop treatment early because of treatment-related, intolerable joint and muscular pain and stiffness, called aromatase inhibitor-associated musculoskeletal symptoms (AIMSS). We previously identified that nociplastic pain, or chronic pain in the absence of tissue damage or inflammation, is associated with increased likelihood of developing AIMSS. Other studies have found that symptom clusters, such as the SPPADE symptoms (sleep disturbance, pain, physical function impairment, anxiety, depression, and low energy/fatigue) are prevalent and co-occur in patients with cancer. Here we examine the prevalence of SPPADE symptoms for patients experiencing AIMSS and willing to enroll on a clinical trial examining use of cannabidiol (CBD) to treat their symptoms. Methods: Patients with stage 0-3 hormone receptor-positive breast cancer experiencing AIMSS (defined as worst joint pain ≥4/10 during prior 7 days that developed or worsened since starting AI therapy) were eligible for enrollment in this single arm, single center phase 2 open label clinical trial (NCT04754399). Enrolled patients completed validated questionnaires at baseline and then received CBD (Epidiolex) for 15 weeks. Patient-reported outcomes (PRO) data was collected serially, including the following questionnaires which addressed SPPADE symptoms: Brief Pain Inventory (BPI) to assess pain, PROMIS Profile 29+2 v2.1 to assess multiple symptoms, and Fibromyalgia Survey (FMS) to assess nociplastic pain. Results: 39 patients enrolled on this clinical trial. The median age at enrollment was 57 (range 37-59) and 21% of patients were over age 70. The majority of patients were white (92%) and average BMI was 31 (SD 6.6). Anastrozole was the most used aromatase inhibitor (74%), followed by exemestane (18%), and letrozole (8%). 5 patients (13%) required concomitant GnRHa therapy. Baseline PRO data was obtained from 37 patients. BPI average pain score over the week prior to enrollment was 5.1 (SD 1.5) and worst pain score was 7.2 (SD 1.3). Pain interference reported on the BPI was 4.1 (SD 2.1). Compared to the general population, enrolled patients reported better physical function (T-score 60.2, SE 3.7), less depression (T-score 45.5, SE 4.7) and fatigue (T-score 46.7, SE 5.1), and similar levels of anxiety (T-score 51, SE 7.1) and sleep disturbance (T-score 49.5, SE 5.9) on the PROMIS Profile. On the FMS, 62% of patients had evidence of nociplastic pain, with average score 13.3 (SD 5.7). The median number of sites of pain in the body reported by patients was 8 (range 1-16). Conclusions: While patients enrolling on an AIMSS clinical trial reported a high degree of daily pain that regularly interferes with their activities, for most patients these symptoms did not appear to have a negative impact on mood, affect, or other symptoms that typically cluster with pain. Though it is difficult to extrapolate results from a small population, the unexpected absence of co-occurring symptoms in this population raises additional questions about the interplay of AIMSS and other symptoms commonly reported in interventional AIMSS studies. Follow-up PRO data will be obtained in this clinical trial, allowing us to examine the impact of CBD use on pain, pain interference, and other patient-reported symptoms, as well as to explore which patients are more likely to obtain benefit from CBD treatment. Funding support provided by Conquer Cancer, the ASCO Foundation and the Rising Tide Foundation for Clinical Cancer Research.
Citation Format: Fleege Nicole, N. Lynn Henry. Evaluating Symptom Clusters in Patients with Breast Cancer Experiencing Aromatase Inhibitor-Associated Musculoskeletal Symptoms [abstract]. In: Proceedings of the 2023 San Antonio Breast Cancer Symposium; 2023 Dec 5-9; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2024;84(9 Suppl):Abstract nr PO1-11-06.