How much do age, chronic illness, and tumor characteristics affect patient survival?

This study investigated the impact of age, comorbidities (the existence of other illnesses), and tumor risk on mortality in men with early-stage prostate cancer.

Accurate estimation of life expectancy is essential to offering the best care to men with early-stage prostate cancer. It is known that the severity of the tumor can predict poorer chance of survival. However, no study has examined the long-term risks associated with the presence of other illnesses in patients with prostate cancer.

Two important categories of mortality exist: other-cause mortality and disease-specific mortality. Other-cause mortality refers to death from something other than prostate cancer. Disease-specific mortality refers to death as a result of the prostate cancer.

This study included 3,183 men with newly diagnosed non-metastatic prostate cancer (cancer that has not spread beyond the prostate). Patient comorbidities, tumor characteristics, treatments and survival were recorded. Comorbidities included: diabetes, bleeding stomach ulcer, chronic lung disease, congestive heart failure, stroke, heart attack, angina (chest pain), cirrhosis (liver disease), arthritis, inflammatory bowel disease, hypertension (high blood pressure) and depression. Patient survival was followed-up for 14 years.

The higher the number of comorbidities the higher the rate of other-cause mortality. 24% of patients with 0 comorbidities, 33% with 1 comorbidity, 46% with 2 comorbidities and 57% with 3 comorbidities died from a non-prostate cancer related cause.

Age at diagnosis influenced the impact of multiple comorbidities. 71% of patients with 3 or more comorbidities who were 75 years or older at diagnosis died within the follow-up time. However, only 26% of the patients younger than 60 and 40% of the patients aged 61-74 died during the same time.

Disease-specific mortality was not affected by the number of comorbidities (10 to 11% in all groups). However, it was linked to the diagnosis of low-risk, medium-risk or high-risk cancer. 3% of low-risk patients, 7% of medium-risk patients, and 18% of high-risk patients died from prostate cancer during the follow-up period.

The authors concluded that older men with more than one comorbidity had a higher risk of other-cause mortality. They suggest that this should be taken into consideration when weighing up the risks of treatment and management strategies for patients.

Patients self-reported their comorbidities. Therefore, the severity of the co-existing conditions could not be taken into account in the analysis.