Malignant disease - Wilms tumour (nephroblastoma)

Question 1

Wilms tumour

(nephroblastoma)

Answer 1

Clinical Features:

• Wilms tumour originates from embryonal renal tissue, commonest renal tumour of childhood. 80% patients present before 5 years age and it is very rarely seen after 10 years of age
• Children present with a large abdominal mass, often found incidentally in an otherwise well child. Other clinical features below

Management:

• Children receive initial chemotherapy followed by delayed nephrectomy, after which the tumour is staged histologically and subsequent treatment is planned according to the surgical and pathological findings
• Radiotherapy is restricted to those with more advanced disease.
• Prognosis is good, with more than 80% of all patients cured. Cure rate for patients with metastatic disease at presentation (∼15%) is over 60%, but relapse carries a poor prognosis

Question 2

Soft tissue sarcomas

Answer 2

• Most common form of soft tissue sarcoma in childhood
• originate from primitive mesenchymal tissue and there are a wide variety of primary sites

Clinical features:

• Head and neck are the most common sites of disease (40%)
• Genitourinary tumours may involve the bladder, paratesticular structures or the female genitourinary tract
• Metastatic disease (lung, liver, bone or bone marrow) is present in approximately 15% of patients at diagnosis and is associated with a particularly poor prognosis

Management:

• Multimodality treatment (chemotherapy, surgery and radiotherapy) is used, dependent on the age of the patient and the site, size and extent of disease
• Overall cure rates are about 65%

Question 3

Bone Tumours

Answer 3

Clinical features:

• Limbs are the most common site.
• Persistent localised bone pain is the characteristic symptom, usually preceding the detection of a mass, and is an indication for early X-ray.
• At diagnosis, most patients are otherwise well

Investigations:

• Plain X-ray is followed by MRI and bone scan.
• A bone X-ray shows destruction and variable periosteal new bone formation.
• In Ewing sarcoma, there is often a substantial soft tissue mass. Chest CT is used to assess for lung metastases and bone marrow sampling to exclude marrow involvement

Management:

• In both tumours, treatment involves the use of combination chemotherapy given before surgery.
• Amputation is avoided by using en bloc resection of tumours with endoprosthetic resection.
• In Ewing sarcoma, radiotherapy is also used in the management of local disease, especially when surgical resection is impossible or incomplete, e.g. in the pelvis or axial skeleton.

Question 4

Bone tumours

Answer 4

Question 5

Retinoblastoma

Answer 5

• Retinoblastoma is a malignant tumour of retinal cells and, although rare, it accounts for about 5% of severe visual impairment in children
• It may affect one or both eyes
• All bilateral tumours are hereditary, as are about 20% of unilateral cases.
• The retinoblastoma susceptibility gene is on chromosome 13, and the pattern of inheritance is dominant, but with incomplete penetrance. Most cases present within the first 3 years of

Investigations:

MRI and examination under anaesthetic. Tumours are frequently multifocal

Question 6

Neuroblastoma

• Prognosis is good, with more than 80% of all patients cured. Cure rate for patients with metastatic disease at presentation (∼15%) is over 60%, but relapse carries a poor prognosis
• biologically unusual tumour in that spontaneous regression sometimes occurs in very young infants
• There is a spectrum of disease from the benign (ganglioneuroma) to the highly malignant (neuroblastoma). Neuroblastoma is most common before the age of 5 years

Answer 6

Investigations:

• Characteristic clinical and radiological features with raised urinary catecholamine levels suggest neuroblastoma
• biopsy is usually obtained and evidence of metastatic disease detected with bone marrow sampling, MIBG (metaiodobenzyl-guanidine) scan with or without a bone scan
• Age and stage of disease at diagnosis are the major factors which influence prognosis