Measuring healthy life expectancy and determinants of poor perceived health: A population-based study among a subset of rare and common cancer survivors

Background: As the survival proportions for rare cancers are on average worse than for common cancers, assessing the expected remaining life years in good health becomes highly relevant. This study aimed to estimate the healthy life expectancy (HLE) of a subset of rare and common cancer survivors, and to assess the determinants of poor perceived health in rare cancer survivors.

Methods: To calculate HLE, survival data from the population-based Netherlands Cancer Registry of survivors of a rare cancer (i.e., ovarian cancer, thyroid cancer, Hodgkin lymphoma, non-Hodgkin lymphoma) (n=21,376) and a common cancer (i.e., colorectal cancer (CRC)) (n=76,949) were combined with quality of life (QoL) data from the PROFILES registry on a random sample of the rare (n=1025) and common cancer (n=2400) survivors. A flexible parametric relative survival model was used to estimate life expectancy (LE) and years of life lost, and multivariate logistic regression was applied to determine factors related to reported poor perceived health.

Results: Patients previously diagnosed with a rare cancer had an average LE of 8-36 years and were expected to spend ≥67 % of their remaining life in good health. CRC survivors had an average LE of 10 years with approximately 65 % of their remaining life expected to spend in good health. For all cancer types, those aged ≥65 years or with stage IV had the lowest HLE. Low socioeconomic status, advanced stage, and having received radiotherapy only were important predictors of poor perceived health among rare cancer survivors.

Conclusion: HLE can provide meaningful perspective for patients and practitioners for all cancer types, including rare cancers. Yet, data on QoL for rare cancers should be routinely collected, as such will serve as an indicator for monitoring and improving cancer care, and for enabling HLE measurements in cancer survivors.