Estimation of potential gain in quality of life from early detection of cervical cancer

Objective To estimate the lifetime gain in the health-related quality of life (HRQOL) from early detection of cervical cancer. Methods A consecutive, cross-sectional sample of 421 patients with cervical cancer was administered the World Health Organization Quality of Life-brief version questionnaires. A nationwide sample of 22,543 patients with invasive cervical cancer (ICC) was collected from the national cancer registry for estimation of lifetime survival function from 1998 to 2007, which was further multiplied by the ratio of HRQOL score functions for patients with ICC and patients with carcinoma in situ (CIS), and summed up over lifetime to obtain expected relative-quality-adjusted survival. The difference between lifetime survival and the expected relative-quality-adjusted survival gives the expected total dissatisfied time during the life course. Results In comparison with patients with CIS postconization, patients with ICC showed consistently lower scores in the physical and psychological domains and that of sexual life after adjustment for other risk factors. The expected years of life lost for an invasive cancer was 6.48 years using the general population as the reference cohort, while the durations of equivalent to living with a very dissatisfied HRQOL were 1.71 and 0.25 for the physical and psychological domains, respectively, and 1.47 years for sexual life. Validation of the extrapolation method based on a subcohort followed from the 6th to the 13th year shows a relative bias of 0.4%. Sensitivity analysis with 37,000 CIS cases as the reference cohort yields a similar result. Conclusions Early detection of cervical cancer not only avoids premature mortality but also prevents long-term living under lower HRQOL scores, including sexual life.