RESUMO
OBJECTIVE: We assessed the feasibility, patient acceptability of and compliance of a new surveillance strategy for ovarian cancer surveillance in women with BRCA mutations, based on assessments of serum CA125 and HE4 every 4 months (Risk of Ovarian Cancer Algorithm (ROCA) arm), compared to Standard of Care (SOC) surveillance with CA125 blood tests and pelvic ultrasounds every 6 months. METHODS: Women were recruited 6/13/16-9/11/17 from an integrated health care system in California for this non-randomized prospective cohort study. Women were invited to participate in a novel serum biomarker surveillance strategy using ROCA or they could opt to be in the standard of care control arm with ultrasound and CA 125 every 6 months. Outcomes assessed included compliance, self-reported distress using the Impact of Event Scale (IES) and cancer anxiety using the Cancer Worry Scale. RESULTS: There were 159 women in the ROCA arm and 43 in the SOC arm. Overall, compliance was higher in the ROCA arm (83.2%) than in SOC (51.9%), p < 0.0001. Based on the IES, ROCA arm women reported less feelings about intrusion and avoidance at 12 months compared to baseline; the difference approached significance for intrusion (7.6% vs 4.1% severe, p = 0.057) and was statistically significant for avoidance (20.8% vs 9.9% severe, p = 0.034). CONCLUSIONS: This pilot demonstrated that compliance was high with blood tests performed every four months for ovarian cancer surveillance. Moreover, ROCA women had lower stress scores over time than SOC women. Given the lack of clinical utility and poor compliance shown with traditional ultrasound and CA125 tests, further investigation is warranted of longitudinal biomarker surveillance for early detection of ovarian cancer.
Assuntos
Antígeno Ca-125/sangue , Proteínas de Membrana/sangue , Neoplasias Ovarianas/sangue , Neoplasias Ovarianas/diagnóstico por imagem , Proteína 2 do Domínio Central WAP de Quatro Dissulfetos/metabolismo , Adulto , Algoritmos , Biomarcadores Tumorais/sangue , Estudos de Viabilidade , Feminino , Humanos , Cooperação do Paciente , Projetos Piloto , Risco , Ultrassonografia , Conduta Expectante/métodosRESUMO
PURPOSE: The objective of this study was to identify and characterize new serum biomarkers in ovarian cancer patients using mass spectrometric protein profiling and specific immunological assays. EXPERIMENTAL DESIGN: Serum samples from 80 cancer patients and 91 healthy women were analyzed by surface enhanced laser desorption and ionization-mass spectrometry (MS) profiling. A candidate biomarker was purified by affinity chromatography, and its sequence was determined by liquid chromatography-tandem MS. An antibody was generated from the synthesized peptide for quantitative validation in the cases and controls. CA125 was determined and compared with the same set of specimens. RESULTS: Using surface enhanced laser desorption and ionization, we found a serum biomarker at approximately 11700 Da, which had peak intensity significantly higher in cases (1.366) compared with controls (0.208, P = 0.002), and subsequently identified this as the alpha chain of haptoglobin. ELISA indicated that Hp-alpha was =2-fold higher in cancer serum compared with normal, benign tumor, and other gynecological cancers (P < 0.05) and had 64% sensitivity at 90% specificity alone and 91% sensitivity and 95% specificity if combined with CA125. CONCLUSIONS: Haptoglobin-derived alpha subunit is a potential marker for ovarian cancer that is complementary to CA125. MS-based protein profiling is a valuable tool for screening protein markers and useful to detect post-translational modification of tumor-associated proteins or abnormal metabolic products. However, confirmation of protein identity with specific antibodies is crucial for clinical application and functional studies.