The Case of the Missing 2020 Cancers: Using Claims Data to Investigate a Deficit in Incident Cancer Case Reports to the New York State Cancer Registry in 2020.

Background: As the February 2022 Surveillance, Epidemiology, and End Results (SEER) Call for Data deadlines approached, the New York State Cancer Registry had received reports for approximately 10% fewer consolidated incident cases for 2020 than expected. We used claims data to examine changes in the volume of cancer claim records during the COVID-19 pandemic and possible contributors to the deficit in cancer reports.

Methods: The New York State (NYS) Statewide Planning and Research Cooperative System (SPARCS) requires reporting of all patient encounters from licensed ambulatory surgery, emergency department, and hospital inpatient and outpatient providers. Each record includes patient demographics and up to 17 diagnosis codes from the (ICD-10-CM). For this project, we extracted 6,725,416 SPARCS records with any malignant neoplasm code for 2018 through June 2021 for NYS residents. Using SAS 9.4, we focused on comparing the cancer-related records for 2020 to the records from 2019.

Results: Overall, there were 5% more cancer-related records in 2019 than in 2018 (2,009,600 vs 1,914,364), but 8.2% fewer records in 2020 (1,844,054 total) than in 2019. Looking by month and year, the number of claims in the first 2 months of 2020 exceeded the numbers from 2019 by 5%. However, a decrease in the number of claims started in March 2020, with the biggest drop in April 2020, where there was a deficit of 38.8% for cancer-related encounter reports relative to the same month the previous year. Although the numbers rose after April, the number of claims for the last half of 2020 was still 4% lower than the same time frame in 2019. There were substantial decreases in the number of records in 2020 for all encounter types and across levels of each covariate examined, including age, sex, race/ethnicity, and facility region of NYS. In analyses of all reporting facilities, facilities in New York City had a more pronounced and more prolonged drop in reporting in 2020 than facilities in the rest of the state.

Conclusion: Although SPARCS data do not provide definitive evidence of decreases in incident cancer diagnoses, these data suggest that there were fewer cancers diagnosed among NYS residents in 2020. Additional analyses are needed to assess the impacts of COVID-19-related delays in cancer diagnosis and treatment on stage at diagnosis and outcomes.