Chung Chang1, Jiabin Chen2, Chi-Hsiang Huang1, Wen-Ying Lee3, Li-Chuan Hsu4, An Jen Chiang5,6. 1. Department of Applied Mathematics, National Sun Yat-sen University, Taiwan, Republic of China. 2. Multidisciplinary Science Research Center, National Sun Yat-sen University, Taiwan, Republic of China. 3. Department of Cancer Center, Kaohsiung Veterans General Hospital, Kaohsiung, Taiwan, Republic of China. 4. Department of Obstetrics and Gynecology, Kaohsiung Veterans General Hospital Pingtung Branch, Pingtung, Taiwan, Republic of China. 5. Department of Obstetrics and Gynecology, Kaohsiung Veterans General Hospital, Kaohsiung, Taiwan, Republic of China. 6. Institute of Biomedical Science, National Sun Yat-sen University, Kaohsiung, Taiwan, Republic of China.
Abstract
OBJECTIVE: The aim of the study was to develop a methodology to identify the best use of a longitudinally measured biomarker in relevance to prognosis. MATERIALS AND METHODS: Data of squamous cell carcinoma antigen (SCC-Ag) from 770 patients with cervical squamous cell carcinoma (SCC) were used. The pretreatment, nadir, and time-dependent SCC-Ag values were analyzed in relevance to disease relapse and death with univariate and multivariate analysis side by side with a variety of available clinicopathologic factors. The predictive power of the significant variates was evaluated by C-index with 5-fold cross validation. RESULTS: The pretreatment, nadir, and time-dependent SCC-Ag were all significant risk factors for both relapse and death in the univariate analysis (p < .05), and the time-dependent SCC-Ag had the highest C-index in both events. The nadir and time-dependent SCC-Ag were both independently significant in response to relapse with International Federation of Gynecology and Obstetrics (FIGO) stage as the covariate, and the latter had a higher C-index (0.745). Only the time-dependent SCC-Ag was independently significant together with FIGO stage in response to death with the C-index at 0.844. CONCLUSIONS: Increases in the serum level of SCC-Ag in cervical SCC patients suggest a higher risk of both relapse and death. The best use of serial SCC-Ag measurements is to include the time-dependent value in prognostic assessment with FIGO stage also accounted for. Cervical SCC patients should be followed up on their levels of SCC-Ag, and prognostic evaluation should be updated with recent measurements.
OBJECTIVE: The aim of the study was to develop a methodology to identify the best use of a longitudinally measured biomarker in relevance to prognosis. MATERIALS AND METHODS: Data of squamous cell carcinoma antigen (SCC-Ag) from 770 patients with cervical squamous cell carcinoma (SCC) were used. The pretreatment, nadir, and time-dependent SCC-Ag values were analyzed in relevance to disease relapse and death with univariate and multivariate analysis side by side with a variety of available clinicopathologic factors. The predictive power of the significant variates was evaluated by C-index with 5-fold cross validation. RESULTS: The pretreatment, nadir, and time-dependent SCC-Ag were all significant risk factors for both relapse and death in the univariate analysis (p < .05), and the time-dependent SCC-Ag had the highest C-index in both events. The nadir and time-dependent SCC-Ag were both independently significant in response to relapse with International Federation of Gynecology and Obstetrics (FIGO) stage as the covariate, and the latter had a higher C-index (0.745). Only the time-dependent SCC-Ag was independently significant together with FIGO stage in response to death with the C-index at 0.844. CONCLUSIONS: Increases in the serum level of SCC-Ag in cervical SCCpatients suggest a higher risk of both relapse and death. The best use of serial SCC-Ag measurements is to include the time-dependent value in prognostic assessment with FIGO stage also accounted for. Cervical SCCpatients should be followed up on their levels of SCC-Ag, and prognostic evaluation should be updated with recent measurements.