Evaluation of coverage, generalisability and validity of the U‐CAN lymphoma biobank in Sweden: A comparison with nationwide registers

Abstract

SummaryValidation of biobanks and large cancer cohorts is essential in ensuring high‐quality research results. We examined the coverage, generalisability and validity of the lymphoma collection of the Uppsala‐Umeå Comprehensive Cancer Consortium (U‐CAN) biobank in Sweden, one of the largest cancer biobanks in Europe. Up until 2022, 889 lymphoma patients in U‐CAN Uppsala had available samples, and 329 in U‐CAN Umeå. Patients diagnosed in the U‐CAN Uppsala area 2011–2021 (n = 843) were linked to the nationwide Swedish Lymphoma Register, and a subset diagnosed before 2019 (n = 727) to population‐based registers. The coverage was 39% of all lymphoma patients between 2011 and 2019 diagnosed in the U‐CAN Uppsala area, with a pandemic decline to 10% during 2020–2021. The patients included had superior overall survival (hazard ratio = 0.70 [95% confidence interval, CI: 0.60–0.82]) than all lymphoma patients in Sweden. They had better performance status, were younger (odds ratio [OR] = 0.21 [95% CI: 0.13–0.34]) and had less comorbidities (OR = 0.66 [95% CI: 0.56–0.78]). However, cause‐specific survival and stage distribution were similar. The questionnaire data captured less comorbidities compared to the national registers. Evaluations of biobanks are important, as even population‐based biobanks such as U‐CAN select younger patients with higher socioeconomical status and better performance status. However, the similar cause‐specific survival as in the registries suggests U‐CANs usefulness for prognostic biomarker studies.