The cancer burden in the oldest-old: Increasing numbers and disparities-A nationwide study in the Netherlands, 1990 to 2019

Abstract

Adults aged =80 years (the oldest-old) comprise the fastest growing age group in Western populations. Yet little is known about their cancer burden. In this nation-wide study, we assessed their trends in incidence, treatment and survival over a 30-year period, and predicted their future cancer incidence. All 2 468 695 incident cancer cases during 1990 to 2019 were selected from the Netherlands Cancer Registry, of whom 386 611 were diagnosed in the oldest-old (16%). The incidence of the oldest-old was predicted until 2032. Net and overall survival (OS) were calculated. Patients were divided into four age groups (<80, 80-84, 85-89 and =90 years). The incidence of the oldest-old doubled between 1990 and 2019 and is expected to grow annually with 5% up to 2032. In virtually all cancers the share of oldest-old patients grew, but declined for prostate cancer (25% in 1990-1994 vs 13% in 2015-2019). The proportion of undetermined disease stage increased with age in most cancers. The application of systemic therapy increased, albeit less pronounced in the oldest-old than their younger counterparts (1990 vs 2019: 12%-34%, 3%-15%, 2%-7% and 1%-3% in <80, 80-84, 85-89 and =90 years old). Five-year OS of the oldest-old patients increased by 7 percentage points (to 26%) between 1990 to 1994 and 2015 to 2019 compared to 19 percentage points (to 63%) in <80 years old. The oldest-old cancer patients are a rapidly growing group who benefitted less from improvements in cancer treatment than younger patients, reflecting the multiple challenges faced in the care of the oldest-old.