Employment status was missing for 44% of the cohort at baseline and approximately half the cohort during follow-up (Table 4).
Discussion
The symptoms experienced by patients that were recorded in claims were significantly higher across multiple categories than matched controls. However, the rates were relatively low, demonstrating the wide variability in the presentation of sarcoma. Patients had a variety of recorded problems, not limited to a lump or pain, but including hematologic, gastric, and cardiac concerns, that differed from those who had no suspected sarcoma. These factors highlight the challenges that may be facing patients who have an undetected sarcoma.
An expected finding was the difference in duration of follow-up between cohorts. This could be due to longer survival of those without a sarcoma diagnosis or due to insurance changes among those who had a sarcoma diagnosis. The absence of death data did not allow for further exploration of this finding within this study. Future research may wish to identify more comprehensive datasets to allow for the objective evaluation of the differences in time to diagnosis and stage of disease and survival, which would be the ultimate goal in order to develop potential strategies to improve patient outcomes.
This study was limited in that the sarcoma diagnosis could not be verified in a clinical record due to the de-identified nature of the claims data used for this study. Prior work has shown that the ICD coding for sarcoma is incomplete6,7; therefore it is likely there are many other patients in the claims dataset who had a suspected sarcoma but who did not have a 171.x code recorded. Hence, this study is limited to a comparison of a cohort for whom the provider specified a sarcoma code in their billing records. While there are gaps in the ability to identify the entire population of sarcoma patients, the patients with ICD codes used in this study are likely true sarcoma cases. Prior work has demonstrated that the presence of these codes accurately reflects a true sarcoma diagnosis.7 However, given the concerns with ICD coding, two sarcoma codes were required on unique days to reduce the risk of single rule-out codes or data entry error. Patients diagnosed with sarcoma demonstrate significantly greater health care resource use across variables as matched controls during the 6-month period leading to diagnosis, supporting the observations within advocacy and patient reports of the challenges faced during the process to reach an accurate diagnosis. This work may provide the initial basis for the development of strategies to more rapidly identify a potential sarcoma. Future research could also evaluate more than 6 months prior to diagnosis, to quantify the duration of time during which these differences versus controls may exist. Additionally, the cost of care may be of interest to future research to better quantify the burden of misdiagnosis on the health care system.
Acknowledgement
The authors would like to acknowledge Yun Fang, MS, for her support in the SAS coding for the analysis of this study.
Corresponding Author
Lisa M. Hess, PhD, Eli Lilly and Company. hess_lisa_m@lilly.com
Disclosures
No funding was received or exchanged in the conceptualization, conduct, data collection, analysis, interpretation, or writing related to this study. This unfunded study was conducted by employees of Eli Lilly and Company.