Validating a linked primary–secondary care data platform for analysis of non-specific cancer symptom pathways: a retrospective study

Patients with suspected cancer frequently present with non-specific symptoms (NSS) that do not meet site-specific referral criteria. Rapid Diagnostic Centres (RDCs) in the UK aim to streamline assessment of these patients, but their evaluation has been limited by the lack of linked longitudinal primary-care data. We conducted a retrospective validation study of 2,021 patients referred to a London RDC between November 2021 and December 2024, linked to primary-care records within the Whole Systems Integrated Care (WSIC) platform. We assessed the feasibility of reconstructing NSS pathways using WSIC and evaluated data completeness and outcome concordance against RDC records.WSIC substantially improved data completeness for frailty, comorbidities, lifestyle factors, healthcare utilisation and diagnostic outcomes compared with RDC records alone. The linked dataset enabled reconstruction of symptom histories, laboratory investigations, prescribing patterns, healthcare contacts and diagnostic outcomes over time, capabilities unavailable from RDC records alone. Cancer ascertainment showed near-complete agreement between datasets, with 74 cancers identified in RDC records and 75 in WSIC. Longitudinal follow-up within WSIC identified an additional 34 cancer diagnoses after RDC discharge.These findings validate WSIC as a reliable platform for reconstructing NSS diagnostic pathways and demonstrate the value of linked primary-secondary care data for early cancer signal detection.