Wilms tumour and renal malignancies: SAQ

This girl has the classic presentation of a Wilms tumour: the painless abdominal mass found by the parent at the bath time, the smooth firm flank mass that does not cross the midline, and the hypertension that accompanies the renal tumour. The task is to reach the imaging, to stage the tumour, and to build the risk-adapted definitive therapy in the specialist centre, while holding the high cure rate of the favourable-histology disease against the worse prognosis of the higher stage and the unfavourable histology. [1]

Question 1 (10 marks)

Outline your immediate diagnostic pathway for this three-year-old girl with the flank mass and the hypertension. [1]

A full-mark answer covers the recognition of the renal tumour, the first-line imaging with the Doppler of the cava, the cross-sectional imaging and the staging, and the avoidance of the biopsy in the typical case, with the referral to the specialist centre. [4]

Recognition and the first decision (2 marks). The painless abdominal mass that does not cross the midline, with the hypertension, declares a renal tumour until the imaging settles it, and the Wilms tumour is the working diagnosis. The first priority is the imaging that confirms the renal origin and excludes the tumour thrombus, and the avoidance of the biopsy that would upstage the tumour. [1]

First-line imaging (3 marks). The abdominal ultrasound with the Doppler of the renal vein and the inferior vena cava is the first test, because it confirms the renal origin, shows the solid character of the mass, and defines the tumour thrombus that changes the surgical plan. The hypertension is controlled with the careful titration of the antihypertensive, and the child is kept calm and pain-free. [9]

Cross-sectional imaging and the staging (3 marks). The computed tomography or the magnetic resonance imaging of the abdomen defines the size, the local extension and the contralateral kidney, and the chest computed tomography is performed in every child because the lung is the commonest site of the metastasis. The bone scan and the brain magnetic resonance imaging are added for the clear cell sarcoma and the malignant rhabdoid tumour, which metastasise to the bone and the brain. [4][9]

Avoidance of the biopsy and the referral (2 marks). In the Children's Oncology Group approach, the radiologically typical tumour proceeds directly to the radical nephrectomy with the lymph node sampling, and the biopsy is avoided because the spill upstages the tumour to the stage three and commits the child to the radiotherapy. The child is referred to the specialist paediatric oncology centre, and the stigmata of the Beckwith-Wiedemann, the WAGR and the hemihypertrophy are sought for the syndromic counselling. [4][6]

Question 2 (10 marks)

Discuss the definitive management once the diagnosis of a localised, favourable-histology Wilms tumour is confirmed, and contrast it with the management of a higher-stage disease and an unfavourable-histology disease. [4]

A full-mark answer reproduces the risk-adapted surgery and chemotherapy for the localised favourable-histology disease, and contrasts it with the higher-stage and the anaplastic disease. [5]

Localised favourable-histology Wilms (4 marks). The treatment is the upfront radical nephrectomy with the lymph node sampling, and the stage one and two favourable histology receive the two-drug regimen of the vincristine at one point five milligrams per square metre per dose weekly capped at two milligrams per dose and the dactinomycin at forty five micrograms per kilogram per course every three weeks, with no radiotherapy. The survival exceeds ninety percent for the stage one disease. [4]

Higher-stage favourable-histology disease (3 marks). The stage three disease receives the three-drug regimen that adds the doxorubicin at forty five milligrams per square metre per course, along with the abdominal radiotherapy, and the survival sits around eighty to ninety percent. The stage four disease, with the lung metastases, receives the three-drug regimen and the radiotherapy to the metastatic sites, with the survival around seventy to eighty percent. The preoperative chemotherapy is an alternative under the SIOP strategy, with the four weeks of the vincristine and the dactinomycin before the nephrectomy. [5][9]

Unfavourable-histology and the aggressive renal tumours (2 marks). The diffuse anaplasia is treated with the intensive regimen that adds the cyclophosphamide, the etoposide and the carboplatin, along with the radiotherapy, and it carries the worse prognosis. The clear cell sarcoma of the kidney is treated with the doxorubicin-based intensive regimen and the radiotherapy, and it requires the bone and the brain imaging. The malignant rhabdoid tumour, defined by the loss of the INI1, carries the worst prognosis of the renal malignancies. [8][9]

Synthesis (1 mark). The fellow who holds the curable favourable-histology disease, the more intensive higher-stage disease and the worse-prognosis anaplastic and aggressive tumours together has the framework that organises the whole topic, and the late-effects surveillance that follows each, with the doxorubicin cardiotoxicity and the renal irradiation at its centre. [4]