Hodgkin lymphoma in children & teenagers — what you need to know

Hodgkin lymphoma is a cancer of the lymphatic system — the network of nodes, vessels, and organs that forms part of the body’s immune system. It arises when abnormal lymphocytes (a type of white blood cell) develop and multiply in the lymph nodes, making them swell. What makes Hodgkin lymphoma distinctive under the microscope is the presence of Reed-Sternberg cells — unusually large, abnormal cells that pathologists use to confirm the diagnosis. Unlike non-Hodgkin lymphoma, which encompasses a much wider group of lymphatic cancers, Hodgkin lymphoma follows a relatively predictable growth pattern, spreads in an orderly manner from one node group to adjacent ones, and typically responds very well to treatment. Childhood Hodgkin lymphoma is one of the most treatable cancers in paediatric oncology, and many children and teenagers go on to lead full, healthy lives after completing treatment.

The most common and visible warning sign is a painless, firm swelling in the neck, collarbone area, armpit, or groin that does not go away over two to four weeks. Unlike swollen glands from an infection, the lumps of Hodgkin lymphoma typically do not hurt, are rubbery in feel, and do not shrink after antibiotics. Other important warning signs include persistent unexplained fever, drenching night sweats that soak clothing or bedding, and unexplained weight loss over a short period (these three together are called “B symptoms” and help doctors classify the disease). Children may also have persistent tiredness, itchy skin with no visible rash, or breathlessness — sometimes caused by lymph nodes in the chest pressing on the airway. If your child has a painless swollen lymph node that has not resolved in four weeks, please ask your doctor for an evaluation. Early assessment is important.

There are two main categories of Hodgkin lymphoma. Classical Hodgkin lymphoma (cHL) accounts for the majority of cases and is itself divided into four subtypes based on the microscopic appearance of the tumour: nodular sclerosis, mixed cellularity, lymphocyte-rich, and lymphocyte-depleted. Nodular sclerosis is by far the most common subtype in teenagers and young adults. The second category, nodular lymphocyte-predominant Hodgkin lymphoma (NLPHL), is much rarer, tends to grow more slowly, and has a different cell type (called a “popcorn cell” or lymphocyte-predominant cell rather than a Reed-Sternberg cell). NLPHL often presents at an early stage and has an excellent outlook with treatment. The distinction between cHL and NLPHL matters because the treatment approach can differ, which is why the biopsy and pathology review are so important before any treatment decisions are made.

The diagnosis begins with a careful history and physical examination, followed by blood tests including a full blood count, erythrocyte sedimentation rate (ESR), and liver and kidney function tests. An imaging scan — usually a CT scan of the chest, neck, abdomen, and pelvis, followed by a PET-CT scan — is done to locate all affected lymph node areas and to assess whether organs outside the lymph nodes are involved. The definitive diagnosis requires a biopsy: a small piece of the enlarged lymph node is removed under anaesthesia and examined by a pathologist who looks for Reed-Sternberg cells. The biopsy result also determines the subtype and the extent of disease, both of which guide the treatment plan. The full staging result is classified from Stage I (one node region affected) through Stage IV (spread to organs outside the lymph system).

Treatment for childhood Hodgkin lymphoma is tailored to the stage and risk group. For most children and teenagers, treatment begins with a course of chemotherapy given in cycles over several months. The specific chemotherapy combination used is chosen by the multidisciplinary team based on the stage, the subtype, the child’s age, and other clinical factors. Interim PET-CT scans are done partway through treatment to assess how well the cancer is responding — this “response-adapted” approach means that children who respond very well early may be able to receive less treatment overall, which reduces long-term side effects. Radiation therapy to involved lymph node areas may be added for some children, typically at lower doses than older treatment approaches used. The CION team reviews every case at a multidisciplinary tumour board before recommending a treatment plan. We do not make rushed decisions on your child’s care.

Whether radiotherapy is needed depends on several factors — the stage of the disease, which lymph node areas are involved, and critically, how well the cancer responds to the initial chemotherapy. Modern paediatric protocols use response-adapted treatment, meaning that children with an excellent early response to chemotherapy may avoid radiotherapy altogether. Where radiation is given, it is targeted precisely at the involved lymph node areas and delivered at the lowest effective dose to reduce long-term effects. Long-term effects of treatment — including effects on growth, heart and lung function, and fertility — are taken seriously by the CION team. Before treatment begins, parents and teenagers are counselled about what to expect, and fertility preservation options are discussed when appropriate for the child’s age. Long-term follow-up care after treatment is an important part of the journey.