[Competitive morbidity ant its impact on life expectancy: evaluation and inclusion in the therapeutic decision...

The treatment decision taken by a multidisciplinary meeting for patients with localized prostate cancer must take into account the clinical stage of the cancer and its histological characteristics, but also the patient's age, general state and any concomitant diseases, as treatment is only beneficial when it induces a reduction of morbidity and specific mortality. The specific survival with or without recurrence after treatment for localized prostate cancer is long, at least more than 10 years. Curative treatment is generally not proposed to men with localized prostate cancer when his probability of survival related to a competitive morbidity (intercurrent medical disease) is estimated to be less than 10 years. The objective of this study was to measure the increase or reduction of the survival probability of a patient with localized prostate cancer according to his competitive morbidity, based on the mean life expectancy of the general population.

Review of the literature.

Studies describing the natural history of prostate cancer show that the impact of treatment on morbidity of the cancer (local and/or metastatic) requires a life expectancy of about 8 to 10 years. The impact of a treatment on specific survival requires a life expectancy of about 13 to 15 years. The exact prevalence of diseases coexisting with prostate cancer is unknown. In the USA, The Index of Coexisting Disease (ICD), which takes into account 14 diseases, appears to be the most reliable tool to measure the competitive morbidity in patients with localized prostate cancer. Each disease is classified into 4 levels of severity (score 0 to 3). A table indicates estimated life expectancies by age-group and by ICD score. All men with a high score (2 to 3) die within 10 years after diagnosis, men with a score of 0 have a better estimated life expectancy according to age than that of the general population.

The upper age limit, theoretically set at 70 years, in order to propose curative treatment for localized prostate cancer needs to be reviewed (the mean life expectancy for a 70-year-old man is 12.9 years in France). According to the ICD, the life expectancy at 70 years is 14.8 years in the case of a score of 0 and 8.4 years in the case of a score of 2. In the case of a score of 2, the impact of curative treatment on localized prostate cancer would be real on morbidity, but not on specific mortality.