Prospective development of a patient reported outcomes (PRO) tool in desmoid tumors: A novel clinical trial endpoint.

Abstract

11022 Background: Desmoid tumors (DT) are locally aggressive and cause significant morbidity. Clinical trials in DT typically utilize response rates and progression free survival as primary endpoints. However, these endpoints do not capture improvements in clinical symptoms. To date, there are no validated PRO tools in DT to capture the patient experience and efficacy of a drug. Methods: A review of the published literature and interviews with sarcoma clinicians were used to formulate a list of signs and symptoms and impact on patients (pts). These were collected to build a conceptual model. DT pts (n = 31) with a range of anatomical locations and presentations were interviewed, initially in an open-ended fashion, followed by interrogating the conceptual model. For the concepts that pts reported, they were asked to rate how disturbing each was on a 0-10 scale (0 being not at all, and 10 being as bad as they can imagine). The pts interview data was then used to refine the conceptual model and generate two new PRO instruments Results: Pt interviews demonstrated that across tumor locations, the most frequent and disturbing symptoms were: ‘muscle’ pain (65% pts, median disturbance (MD) of 6.8), ‘nerve’ pain (73%, MD 6.0), and fatigue (65%, MD 5.0). Some symptoms were specific to tumor locations, especially abdominal tumors. Restricted range of motion (68%, MD 4.0), fear (84%, MD 6.5), sleep disturbance (77%, MD 7.5) , disfigurement (81%, MD 6.8), and impact on daily activities (65%, MD 6.8) were the most frequent and disturbing impact on pts lives. These concepts were then used to develop two new PRO instruments: the sign and symptom PRO includes 11 items; the impact on pts lives instrument includes 17 items. The instruments vary in asking pts about the last 24 hours, or the last week. Conclusions: This is the first validated PRO tool in DT. This tool adequately captures symptoms central to the DT pts experience and its impacts on their lives. The instruments are ready for implementation in a DT clinical trial for further evaluation of their measurement properties.