Paediatrics: Principles of follow-up

Principles of follow-up

Follow-up after completion of treatment is focused on disease recurrence and long-term adverse effects of cancer and its treatment.

Monitoring for disease recurrence

This involves clinical review, combined with imaging or laboratory testing to pick up pre-symptomatic recurrence, which may be amenable to fur-ther attempts at curative treatment. For example:

·  CXRs and abdominal US: Hodgkin’s disease.

·  MRI scans: CNS tumours.

·  Urine VMA and HVA: neuroblastoma.

·  Serum AFP and hCG: GCTs.

·  Peripheral blood counts: leukaemia.

Monitoring for late effects of treatment

This is a growing discipline, since there is now a childhood cancer survivor for every 900 adults. Monitoring is focused on the following.

Late effects of radiotherapy

May occur months or years after treatment has been completed. Sequelae usually progressive and irreversible, and will depend on sites, dose, mode of treatment, and age of patient at time of treatment.

Growth sequelae

·  Direct effects on epiphyseal plates.

·  Growth hormone deficiency from hypothalamic/pituitary damage.

·  Muscle damage and avascular necrosis of bone.

CNS sequelae

·  Somnolence and tiredness.

·  Hypothalamic and pituitary damage.

·  Intellectual effects: commonly reduced numeracy and short-term memory.

·  Radiation myelitis.

·  Eyes: cataracts, retinal damage.

·  Other organ system sequelae

·  Gonads: infertility/hypogonadism.

‘Second’ primary malignancies

Risk of 4–6% of occurrence within radiotherapy field. Common second malignancies include solid tumours occurring in the field of radiotherapy, as well as non-melanoma skin cancers. Epithelial tumours predominate.

Late effects of chemotherapy

Sequelae depend on age at the time of exposure, drugs and doses. Well recognized long-term toxicities include:

·  Cardiotoxicity following anthracyclines.

·  Nephrotoxicity following platinum drugs and alkylating agents.

·  Pulmonary fibrosis following bleomycin.

·Impaired fertility following alkylating agents.

·Ototoxicity following antibiotics.

·Second malignancies related to chemotherapy include s leukaemia and myelodysplastic syndrome associated with topoisomerase II inhibitors and alkylating agents.

Fertility

·This is affected by gonadotoxic chemotherapy and by radiotherapy fields that impinge on the gonads.

·The younger the patient when treated, the better the prognosis for future fertility.

·More spermatic recovery is seen after chemotherapy than radiotherapy.

·Risk of gonadotrophin deficiency greatest for radiotherapy directed towards suprasellar and nasopharyngeal tumours, but fertility may be preserved with aid of pulsatile gonadotrophin-releasing hormone (GnRH) therapy.

Quality of survival

It is understood that the long-term effects of treatment go beyond the purely physical consequences of treatment and this is an evolving area of clinical research. Cancer survivors (and their family members) are at increased risk of impaired psychosocial wellbeing. Risk is not clearly as-sociated with a specific cancer type or treatment and is likely to be multi-factorial in origin. Survivors are also at increased risk for needing special education and, as they enter adulthood, unemployment or underemploy-ment