Medical assessment of adverse health outcomes in Dutch childhood cancer survivors; a nationwide project (DCOG LATER study)
DCOG LATER substudy: Sexual function and psychosexual development in long-term childhood cancer survivors

Advances in diagnosis and treatment of childhood cancer over the last decades
have dramatically increased long-term survival. As a result, the number of
childhood cancer survivors (CCS) is growing and it has become increasingly
clear that the former disease and its treatment can significantly impair
long-term health and Health-Related Quality Of Life (HRQoL). More insight into
the consequences of childhood cancer and its treatment is needed to develop
optimal care for survivors of childhood cancer and provide interventions that
will improve life after cancer.
Cancer and its treatment, as well as several late effects of treatment, may
damage one or more of the physiological systems needed for a healthy sexual
response and affect developing sexual behaviors, attitudes and identity. It may
put the patient at risk for delays in achieving psychosexual milestones and an
impaired gender identity, factors which in turn may also influence sexual
behaviour and function later in life. Only two studies have assessed sexual
function in CCS. However, the impact of previous cancer treatment on different
biological as well as psychosocial factors involved in sexual behaviour have
not been studied in detail.
This project is part of the multidisciplinary Dutch Childhood Oncology Group
(DCOG) program for patient care and research into long-term effects after
childhood cancer (LATER) and currently involves over 20 specific PhD projects
focusing on various late effects.

This DCOG-LATER project proposal aims to characterize the overall, disease and
treatment-related risks of sexual dysfunction and delays in psychosexual
development in a Dutch cohort of 5-year CCS treated in the period 1960-2001 and
to evaluate the extent to which sexual dysfunction is associated with distress.
In addition, the extent to which sexual dysfunctions may be associated with
other major biological, psychological and sociocultural risk factors for sexual
dysfunction will be examined.
Specific aims include, to study in male and female 5-year survivors of
childhood cancer in the Netherlands:
1) the prevalence of sexual dysfunctions (compared to controls)
2) disease and treatment related risk factors for sexual dysfunction
(biological risk factors)
3) the extent to which sexual dysfunctions are associated with distress
(psychological factors)
4) the effects of relationship factors on sexual dysfunctions
(socio-cultural factors)
5) the effects of other major biological, psychological and sociocultural
risk factors on sexual dysfunctions (age at diagnosis, age at study, medication
use, co-morbidities, depression, religion, life style factors)
6) the prevalence of delays in psychosexual development (compared to
controls)
7) disease and treatment related risk factors for delays in psychosexual
development and their association with sexual dysfunctions
8) the correlation between sexual dysfunctions and the Free Androgen
Index (FAI)

The general study design involves a nation-wide multicentre retrospective
cohort study. All CCS in the Netherlands are offered regular follow-up
screening according to national, uniform, evidence-based guidelines in one of
the seven Dutch long-term follow-up clinics, and for this substudy on sexual
function and psychosexual development all eligible CCS (n=5166 adults) will be
invited to participate in the proposed study. In addition 1500 controls, both
siblings and controls from the general population, will be invited to
participate. Comparison with siblings allows to control for genetic background,
the microsocial status and attitude towards sex. Comparing CCS with controls
from the general population will reveal differences on a macrosocial
environmental level.
For the specific project described in the current proposal survivors will be
asked to complete questionnaires on sexual function, sexual distress and
psychosexual development including their satisfaction with past and current
relationships. In addition, serum levels of total testosterone and sex-hormone
binding globuline (SHBG) will be in order to distinguish endocrine causes of
sexual dysfuntion from psychosocial causes.

For all participants (patients and controls) the study consists of completing 3
questionnaires (sexual function, sexual distress, psychosexual development
including relationship factors) and providing a blood sample (they can also
choose to not provide a blood sample and only compltete the questionnaire.
Completing the questionnaire will take approximately 35-45 minutes.
Bloodsampling in patients will primarily be performed at the same time that
blood is drawn for patient care so that no extra venapuncture is required. For
patients not requiring blood sampling for patientcare or not willing to
participate in patient care, and controls, venapunction will be performed for
research purposes only. However, both questionnaires and blood sampling carry
along little to no risk. The total study time including questionnaires and
venapunction will be 50 minutes maximum.