History
Presenting Complaint
Most patients present with no specific symptoms. Parents or children usually notice an abdominal mass incidentally. About one third of patients have other symptoms, usually fevers, weight loss, haematuria, anorexia, nausea or vomiting. Patients with metastatic disease may present with symptoms related to metastases.
Past History
A past history of congenital abnormalities should be elicited. The commonly associated findings include aniridia, mental retardation, or genitourinary malformations. The three common congenital syndromes are:
- WAGR syndrome (Wilms Tumour, Aniridia, Genitourinary malformations and mental Retardation), due to deletion of the WT1 gene on chromosome 11
- Beckwith-Wiedermann Syndrome, due to errors in a gene locus on chromosome 11 (not WT1)
- Denys-Drash Syndrome, due to a point mutation in WT1
Medications
Nil specific
Allergies
Nil specific
Family History
Family history of malignancy syndromes (eg. Li Fraumeni) may be related to the development of nephroblastoma.
Social History
The child's ability to attend treatment and social supports should be elicited.
Examination
Examination should focus on:
- Extent of local disease
- Presence of metastatic disease
- Detection of the presence of underlying syndromes (WAGR/Denys-Drash/Beckwith-Wiedermann)
Hypertension and haematuria are not uncommon findings. Coagulopathy is uncommon
Imaging
Abdominal ultrasound is a good first investigation. It allows:
- Determination of origin of abdominal mass
- Presence of renal obstruction
- Presence and status of contralateral kidney
- Imaging with non-ionising radiation
CT of the abdomen is also useful in identifying the extent of local disease and the presence of local metastases or bilateral nephroblastoma. MRI may also play a role. The staging of the contralateral kidney is controversial - some argue that imaging alone is sufficient whereas others insist that the contralateral kidney must be surgically explored during treatment of the definitely involved kidney. Also controversial is the use of CT to determine the presence of pulmonary metastases (versus plain chest X-ray).
Histological Diagnosis
The histological diagnosis of nephroblastoma is controversial.
- SIOP recommends neoadjuvant therapy with chemotherapy and/or radiotherapy to downstage the tumour and reduce the risk of tumour spillage.
- COG recommends initial surgical excision followed by adjuvant treatments as required
The ideal method has not yet been determined. Proponents of the SIOP method believe that neo-adjuvant treatment allows for reduced tumour spillage and reduced surgical morbidity due to smaller operations. Opponents say that SIOP can render diagnosis of the tumour difficult, and also claim that up to 5-6% of patients are treated for benign or non-nephroblastoma conditions.
Staging
Staging varies depending on the organisation (SIOP and COG).
SIOP Staging
Stage | Description |
---|---|
I | Completely resected; tumour is limited to the kidney; or if beyond the kidney the tumour is confined by the pseudocapsule |
II | Completely resected; tumour directly invades adjacent structures such the IVC, adrenal glands or pancreas etc. |
III | Incompletely excised tumour, due to * Involvement of surgical margins * Involvement of abdominal lymph nodes * Peritoneal contamination by tumour or intraoperatively * Residual abdominal tumour * Non-contigous resection / piecemeal resection * Biopsy of tumour prior to neoadjuvant chemotherapy * Presence of necrotic tumour or chemotherapy changes in margins or nodes |
IV | Haematogenous or non-abdominal lymph node metastases |
V | Bilateral tumours; each tumour should be sub-staged as above |
COG Staging
Stage | Description |
---|---|
I | Completely resected; tumour is limited to the kidney and the renal capsule is intact |
II | Completely resected; tumour directly invades adjacent structures such the IVC, adrenal glands or pancreas etc. |
III | Incompletely excised tumour, due to * Involvement of surgical margins * Involvement of abdominal lymph nodes * Peritoneal contamination by tumour or intraoperatively * Residual abdominal tumour * Non-contigous resection / piecemeal resection |
IV | Haematogenous or non-abdominal lymph node metastases |
V | Bilateral tumours; each tumour should be sub-staged as above |