Germ Cell Tumour

Germ cells are the cells that form eggs and sperm. During early development they travel through the embryo to the ovaries or testes, and tumours can arise wherever germ cells settle. In children this means germ cell tumours may occur in the ovary or testis, or in extragonadal sites along the midline of the body such as the sacrococcygeal region near the tailbone, the abdomen, the chest and the brain.

Germ cell tumours range from benign teratomas, which contain a mixture of mature tissues, to malignant tumours such as yolk sac tumour, germinoma and choriocarcinoma, and many tumours contain more than one component. They occur in two main age groups: infants and very young children, and adolescents. The treatment approach differs between these groups.

Presentation depends on the site. A testicular tumour usually presents as a painless swelling of the testis. Ovarian tumours may cause abdominal pain or swelling, and sometimes present acutely if the ovary twists. Sacrococcygeal teratomas are often visible at birth or found on antenatal scans, while tumours deeper in the abdomen or chest may cause pain, constipation, urinary symptoms or breathlessness.

Investigations include ultrasound and CT or MRI to define the tumour, and blood tests for tumour markers, particularly alpha-fetoprotein (AFP) and beta-hCG, which are raised by many malignant germ cell tumours and are very useful for diagnosis and monitoring. Chest imaging checks for spread. Because tumour markers and imaging are often characteristic, many germ cell tumours are removed without a biopsy first.

Germ cell tumours are managed within a multidisciplinary children's cancer service. Surgery is the primary treatment for most tumours and is curative on its own for benign teratomas and for many small malignant tumours that are completely removed. When a malignant tumour is more advanced, has spread, or cannot be safely removed at the outset, chemotherapy is given, and these tumours are generally very sensitive to it. Chemotherapy may be given first to shrink a large tumour, followed by surgery to remove what remains.

Radiotherapy has a limited role in childhood germ cell tumours outside the brain. Your child's surgeon coordinates closely with the oncologists on the timing of surgery and on the need for any treatment afterwards, guided by the pathology results and the behaviour of the tumour markers.

The operation depends on where the tumour is. A testicular tumour is removed through a groin incision, taking the testis and spermatic cord together (inguinal orchidectomy). For an ovarian tumour the aim wherever possible is to remove the tumour while preserving the other ovary and, in appropriate cases, part of the affected ovary, to protect future fertility. Sacrococcygeal teratomas are removed together with the coccyx (tailbone), and abdominal or chest tumours are approached according to their position.

The surgeon takes care to remove the tumour intact, as rupture can affect staging, and samples fluid and any suspicious tissue for staging. The operation is performed under general anaesthesia by a paediatric surgical team, and keyhole techniques are used where they are safe and appropriate.

Recovery is usually straightforward. Children having a groin operation often go home the same or next day, while abdominal, chest or sacrococcygeal surgery involves a longer stay. The treating team will provide guidance on wound care, pain relief and returning to normal activity.

Follow-up relies heavily on tumour marker blood tests, which are checked regularly and should fall to normal after successful treatment; a rising level can indicate recurrence before it is visible on scans. Ultrasound or other imaging is also performed at intervals for several years. Children who have had a sacrococcygeal teratoma need follow-up of bowel and bladder function. Where fertility could be affected, the team will discuss this with you and, for adolescents, may offer fertility preservation options before treatment begins.