Scoping Review of Point-of-Care tests used to detect Cancer

Problem

Diagnostic testing and timely triaging of patients are crucial steps in cancer care pathways. Access to diagnostic tests and effective triaging of patients with possible cancer can be improved by incorporating the use of point of care tests (POCTs) at primary care level. Despite the availability of several POCTs for cancer, adoption in clinical practice is negligible. Paucity of published literature and information regarding the availability and potential of POCTs may contribute to the lack of uptake by clinicians. The aim of this scoping review was to systematically identify POCTs available to detect cancer.

Approach

Comprehensive literature searches were performed in OVID MEDLINE, OVID EMBASE, Cochrane CENTRAL, INHATA, and Clinicaltrials.gov between March 2009 - March 2019. The search strategy combined several MeSH and free-text terms for "cancer" and "point of care test". Studies were screened by title and abstract independently by two reviewers and discrepancies were adjudicated by a third reviewer. Primary studies were eligible if they included an in-vitro POCT used to detect cancer in clinical populations during or very close to the time of consultation with results available within the same practice visit. Literature on POCTs used solely for monitoring, point of care ultrasonography and imaging, and pre-clinical assay refinement studies were excluded. POCTs primarily intended for diseases that were precursors to cancer were also excluded. Extracted data included diagnostic metrics of POCT, cancer type, and time to results.

Findings

Literature searches retrieved 6815 studies of which 248 were screened for full text. From the included studies, 17 unique POCTs were identified. Most POCTs were intended for colorectal (n=6) and bladder cancer (n=4) followed by breast (n=3), prostate (n=2), lung (n=1) and multiple myeloma (n=1). Time to test results for the POCTs varied from 3 minutes to 60 minutes with a median time of 10 minutes. POCTs intended for colorectal cancer required faeces as a test sample and urine was required for bladder cancer POCTs. For prostate and multiple myeloma finger-prick blood samples were required. Breath samples were required for both breast and lung cancer POCTs.

Consequences

Current POCTs literature for cancer is largely observational and research to support uptake in clinical practice is lacking. Despite the abundance of research investigating POCTs for cancer, very few POCTs progress to product development. This review aimed to capture literature through scientific databases and registries, however it is possible that POCTs not published on scientific platforms were not identified in this review. For this reason, additional hand searches of web pages were conducted in December 2020 to identify POCTs not published on scientific databases (for example on test developer websites). These findings will be incorporated with updated searches of databases that were orignally searched to allow inclusion of few additional available POCTs for cancer.