Approximately 3,000 new cases of cancer in children are diagnosed each year in Kenya. The three most common ones arise from lymphatic glands (lymphoma), blood (leukaemia), and retina — the part of the eye that perceives light (retinoblastoma).
One in every 20 cases of cancer in Kenya occur in children below the age of 15 years, but most go undiagnosed or confused for other more common diseases like malaria, anaemia, or infections.
The fourth most frequent cancer in children in the country is Wilms’ tumour, which occurs in the kidneys. It occurs in about one in every 12 cases of cancers , and affects children between the age of two and five years. It occurs in one kidney, but can be found in both organs when the disease is advanced.
A typical sign of kidney cancer in the early stages is painless swelling in the tummy, which can be discovered during bathing. Health professionals who are in the habit of carrying out thorough clinical assessment of children during visits to doctors also pick up a number of cases before even parents realise that there is a problem.
If left undetected for more than a couple of months, the tumour may spread beyond the affected kidney into the rest of the abdomen and even affect the other kidney.
The commonly affected parts through blood spread are the liver and the lungs. Nerves and bone involvement may occasionally occur from some uncommon variants of the cancers (referred to as rhabdoid and clear cell types).
It involves taking scans (ultra sound, or computer x-ray) of the tummy and the chest. Another procedure is to suck cells from the kidney with an ordinary needle and syringe (fine needle aspirate) to confirm the cause of the swelling and whether the cells are cancerous or not.
Material for definite diagnosis and determination of the actual extent of local spread is done during surgery, which entails complete removal of the affected kidney.
Depending on the occurrence of the disease and rate of progression, Wilms’ tumour may range from a few grammes to several kilogrammes.
Specific treatment entails chemotherapy before and after surgery and radiotherapy in the affected area a few months after surgery. Compared to other cancers, Wilms’ tumour is relatively easy to treat and has an impressive cure rate if caught early enough.
As many as eight out of 10 children are cured when diagnosis is made early enough. Parents and health workers who look after children must always make an effort to detect this potentially curable cancer early by regularly examining tummies of children between the ages of one to six years.
Those with suspicious swellings should be taken for review by a paediatrician, who would then order confirmatory diagnostic tests.
It should be noted that the most common cause of tummy swelling in children is not cancer; a large spleen or liver are more common and are often associated with other common medical conditions like malaria, infections, and other conditions like sickle cell anaemia.