Evaluation of a 5-Marker Blood Test for Colorectal Cancer Early Detection in a Colorectal Cancer Screening Setting
Menée sur 1 200 témoins et sur 460 patients présentant un adénome de stade avancé, un carcinome in situ ou un cancer du côlon-rectum, cette étude évalue, par rapport au test immunochimique de recherche de sang occulte dans les selles et par rapport au test au gaïac, la performance d'un test sanguin, basé sur la recherche de 5 biomarqueurs (antigène carcino-embryonnaire, ostéopontine, séprase, ferritine, anticorps anti-p53), pour détecter précocement un cancer colorectal
Purpose : In initial studies that included colorectal cancer (CRC) patients undergoing diagnostic colonoscopy we had identified a serum marker combination able to detect CRC with similar diagnostic performance as fecal immunological test (FIT). In this study we aimed to validate the results in participants of a large CRC screening study conducted in the average-risk, asymptomatic screening population.
Experimental Design : We tested serum samples from 1200 controls, 420 advanced adenoma patients, 4 carcinoma in situ patients and 36 CRC patients with a 5-marker blood test (carcinoembryonic antigen (CEA)+anti-p53+osteopontin+seprase+ferritin). The diagnostic performance of individual markers and marker combinations was assessed and compared with stool test results. Results: AUCs for the detection of CRC and advanced adenomas with the 5-marker blood test were 0.78 (95%CI: 0.68-0.87) and 0.56 (95%CI: 0.53-0.59), respectively, which now is comparable with guaiac-based fecal occult blood test (gFOBT) but inferior to FIT. With cutoffs yielding specificities of 80%, 90% and 95% the sensitivities for the detection of CRC were 64%, 50% and 42% and early-stage cancers were detected as well as late-stage cancers. For osteopontin, seprase and ferritin the diagnostic performance in the screening setting was reduced compared to previous studies in diagnostic settings while CEA and anti-p53 showed similar diagnostic performance in both settings.
Conclusions : Performance of the 5-marker blood test under screening conditions is inferior to FIT even though it is still comparable to the performance of gFOBT. CEA and anti-p53 could contribute to the development of a multiple marker blood-based test for early detection of CRC.
Clinical Cancer Research , résumé, 2015