Advances in diagnosis and treatment of childhood cancer over the last decades have dramatically increased long-term survival. As a result, the numbers of childhood cancer survivors are growing and it has become increasingly clear that the former disease and its treatment can significantly impair long-term health. The need for long-term follow-up is uniformly recognized. Research focusing on identification and characterization of high-risk populations is an essential foundation on which to build evidence-based recommendations for long-term follow-up. Furthermore, research focusing on more accurate screening tests and effective interventions is needed to reduce excess morbidity and mortality in survivors.

Plan of investigation
Participating centres

The DCOG LATER Study will be lead and coordinated by the DCOG LATER group. The DCOG LATER group is one of the Task Groups of the Dutch Childhood Oncology Group (or SKION in Dutch). DCOG LATER is a collaborative group of clinicians, researchers and a representative from the patient-parent organization VOKK and is responsible for care and research for survivors of childhood cancer.

Plan of investigation

Between 2012 and 2016  all more than 6000 identified 5-year survivors of childhood cancer in the Netherlands (diagnosed before 2002) and additional control groups will be invited to the seven Late Effects Clinics to undergo a general medical exam, several screening tests according to the guidelines, additional tests and a questionnaire survey.

Retrospective cohort study of 5-year survivors of childhood cancer with cross-sectional assessment of health status and future prospective follow-up. Controls for the several studies will be recruited among survivors not exposed to treatments of interest or siblings of survivors.

Study Population
All patients who were treated for childhood cancer (before age 18) in one of the seven Pediatric Oncology Centers before January 2002 and who survived for at least 5 years will be included in the LATER study. For several research questions  adult siblings of survivors will be approached as controls in order to enable comparison with a control group matched on socioeconomic status and genetic factors.

Data Collection
All participants will undergo a full medical assessment by a physician and will be asked to fill out a health and risk factor questionnaire. The questionnaire inquires about medical history, disease symptoms, medication use, education, socioeconomic status, life style risk factors for chronic diseases (smoking, alcohol use, body mass index, physical activity) and quality of life.

The clinical evaluation includes a medical history and a physical examination, according to the national standardised follow-up screening recommendations. In addition, all survivors will be asked to provide an additional blood sample, for future research. This will enable us to conduct studies on the influence of genetic factors on treatment-related adverse effects in childhood cancer survivors. Also, biomarkers for early identification of adverse health outcomes can be examined. DNA (of buffy coat) will be isolated, and serum and DNA will be stored centrally in a biobank held by DCOG.  

Project Groups
The DCOG LATER set up several project groups structured by organ system, i.e. second tumors, endocrinological late effects/BMI, cardiovascular late effects, fertility/ bone density, renal late effects, pulmonary late effects/fatigue, psychosocial late effects, various late effects,  neurology/neurocognitive problems, radiation therapy, medical informatics and epidemiology to design the different sub-studies of the DCOG LATER Study.  Each project group involved experts from various disciplines.

Focus groups in collaboration with the VOKK
To identify barriers and challenges for survivors to participate in this study we invited a group of childhood cancer survivors and parents in a focus group. The results of this focus group are described in addendum I. We conclude that although there were several remarks, the general conclusion was that survivors would like to participate in the study. We will try to incorporate the advices / wishes of the survivors in the practical implementation of the study in the 7 different university centres.

Participating centres
Participating centres are located in:


  • Academic Medical Centre - Emma Children's Hospital (AMC/EKZ)
  • VU University Medical Center (VUmc)


  • University Medical Center Groningen (UMCG) - Beatrix Children's Hospital


  • Radboud University Medical Center Nijmegen (UMCN)


  • Leiden University Medical Center (LUMC) - Willem-Alexander Children's Hospital


  • Erasmus MC - Sophia Children's Hospital (Erasmus MC-Sophia)


  • University Medical Center Utrecht/ Wilhelmina Children's hospital (AZU/WKZ)