Immunotherapy & targeted therapy for childhood cancer — a parent's guide

Immunotherapy and targeted therapy are both alternatives or additions to conventional chemotherapy, but they work in different ways. Immunotherapy works by helping your child's own immune system recognise and attack cancer cells more effectively. Targeted therapy works by blocking specific signals or proteins that certain cancer cells depend on to survive and grow. Whether one, both, or neither is suitable depends entirely on the type of cancer your child has, the specific biological features of their tumour, and what molecular testing shows. Your oncologist will explain which approach is relevant and why after reviewing the full diagnostic picture.

Immunotherapy has been studied in children and is used in selected childhood cancers where evidence supports it. The side effect profile is different from chemotherapy. Rather than the bone marrow suppression and hair loss associated with many chemotherapy medicines, immunotherapy can trigger immune-related reactions — the immune system can sometimes become overactive and affect healthy tissues, including the skin, gut, lungs, or liver. These reactions are usually manageable when caught early, which is why children receiving immunotherapy are monitored closely at each visit. Your oncologist will discuss the specific risks relevant to the type of immunotherapy your child may receive before treatment begins.

Targeted therapy is not available for all childhood cancers. It is used when a tumour has a specific biological target — a mutated gene, a rearranged chromosome, or an overactive protein — that can be blocked by a targeting medicine. Molecular testing of the tumour tissue (and sometimes the blood) is needed to identify whether a suitable target is present. Some leukaemias, certain lymphomas, selected brain tumours, and some solid tumours have well-established targetable features. For many childhood cancers, targeted therapy is given alongside chemotherapy rather than instead of it. The tumour board at CION reviews each child's molecular test results and recommends targeted therapy only where the evidence supports its use.

Molecular testing (also called genomic or genetic tumour testing) is an analysis of the DNA and proteins inside your child's cancer cells to identify specific mutations or abnormalities that drive the tumour's growth. This testing is typically done on a biopsy sample or surgically removed tumour tissue. It is essential before targeted therapy can be considered — without knowing whether the right target is present in your child's tumour, there is no way to predict whether a targeting medicine would work. Molecular testing results take time, typically one to three weeks. Your oncologist will explain what was tested, what the results mean, and whether a targetable feature was found.

The duration depends on the cancer type, the specific treatment being used, and how the cancer responds. Some targeted therapy courses are given for a defined number of cycles alongside chemotherapy and then stopped. Others are continued as long-term oral medicines taken daily for months or years. Some immunotherapy approaches are given as infusions at regular intervals for a fixed period. Your oncologist will give you the planned treatment timeline once the full picture is clear, and will review the plan at each assessment point. Side effects, response to treatment, and the child's overall wellbeing all influence whether the schedule changes.

At CION Cancer Clinics, every child's case is reviewed by a tumour board — a group of medical, surgical, and radiation oncologists who together agree on the most appropriate treatment plan. When targeted therapy or immunotherapy is being considered, the board reviews the molecular testing results alongside the imaging, pathology, the child's age and overall health, and what the current evidence supports. No single doctor makes this decision alone. The plan — including whether immunotherapy or targeted therapy is recommended, and in what combination — is then explained to the family in a dedicated 45-minute consultation so you have time to ask every question you need to.