title: Survival differences between patients with Hodgkin lymphoma treated inside and outside clinical trials. A study based on the EORTC-Netherlands Cancer Registry linked data with 20 years of follow-up.
abstract: The survival of patients diagnosed with Hodgkin lymphoma (HL) has improved from 70% to 90% in clinical trials. However, population-based data has shown lower survival. In this study, clinical trial data were linked with cancer registry to identify trial and non-trial participants and differences in overall survival and associated factors were assessed. In 1986-2004, 27% of HL patients aged 15-70 years participated in clinical trials. Compared to non-trial participants, trial participants were younger (median age, 31 vs. 34 years), had staging registered more accurately and had an 8% higher 20-year survival rate (73% vs. 65%). After adjusting for baseline differences, no differences in survival (hazard ratio = 0·96, 95% confidence interval 0·82-1·12), or in subgroup analysis according to stage, remained. Over time, increased administration of chemotherapy in combination with radiotherapy, together with the decreased use of radiotherapy alone was observed among the trial population. This trend was later followed in non-trial participants, coinciding with a similar 'take-up' in survival. The observed superior survival among patients with HL treated in clinical trials can be largely explained by the differences in baseline characteristics, particularly younger age. High trial participation rate and centralized expertise facilitates the implementation of trial findings to real-world practice.
authors.affiliation: Department of Statistics, The European Organisation for Research and Treatment of Cancer (EORTC), Brussels, Belgium.
authors.forename: Lifang
authors.initials: L
authors.lastname: Liu
authors.affiliation: Department of Statistics, The European Organisation for Research and Treatment of Cancer (EORTC), Brussels, Belgium.
authors.forename: Francesco
authors.initials: F
authors.lastname: Giusti
authors.affiliation: Netherlands Comprehensive Cancer Organisation (IKNL), Utrecht, the Netherlands.|Division of Psychosocial Research and Epidemiology, the Netherlands Cancer Institute (NKI), Amsterdam, the Netherlands.
authors.forename: Michael
authors.initials: M
authors.lastname: Schaapveld
authors.affiliation: Department of Radiation Oncology, the Netherlands Cancer Institute (NKI), Amsterdam, the Netherlands.
authors.forename: Berthe
authors.initials: B
authors.lastname: Aleman
authors.affiliation: Department of Hematology, Erasmus MC Cancer Institute, Rotterdam, the Netherlands.
authors.forename: Pieternella
authors.initials: P
authors.lastname: Lugtenburg
authors.affiliation: Department of Radiation Oncology, ZNA Middelheim and University of Antwerp, Antwerp, Belgium.
authors.forename: Paul
authors.initials: P
authors.lastname: Meijnders
authors.affiliation: Department of Haematology, Rigshospitalet Copenhagen University Hospital, Copenhagen, Denmark.
authors.forename: Martin
authors.initials: M
authors.lastname: Hutchings
authors.affiliation: Netherlands Comprehensive Cancer Organisation (IKNL), Utrecht, the Netherlands.
authors.forename: Valery
authors.initials: V
authors.lastname: Lemmens
authors.affiliation: Department of Statistics, The European Organisation for Research and Treatment of Cancer (EORTC), Brussels, Belgium.
authors.forename: Jan
authors.initials: J
authors.lastname: Bogaerts
authors.affiliation: Netherlands Comprehensive Cancer Organisation (IKNL), Utrecht, the Netherlands.
authors.forename: Otto
authors.initials: O
authors.lastname: Visser
mesh_terms: D000293:Adolescent; D000328:Adult; D000367:Age Factors; D000368:Aged; D000369:Aged, 80 and over; D000971:Antineoplastic Combined Chemotherapy Protocols / Q000627:therapeutic use; D002986:Clinical Trials as Topic; D003131:Combined Modality Therapy; D005500:Follow-Up Studies; D006689:Hodgkin Disease / Q000453:epidemiology / Q000401:mortality* / Q000628:therapy; D006801:Humans; D008875:Middle Aged; D009426:Netherlands / Q000453:epidemiology; D011878:Radiotherapy; D012042:Registries; D015996:Survival Rate; D055815:Young Adult
keywords: clinical trials; deterministic data linkage; hodgkin lymphoma; overall survival; population-based cancer registry