Understanding cancers in childhood

Dr. Sylvester Ikhisemojie

When this topic was first discussed on this page about nine years ago, many readers were incredulous that children could even suffer from cancer. At the time, we broadly addressed the issues surrounding childhood malignant diseases as they are more formally called.

This week, we shall be discussing just a small subset of the entire spectrum of these cancers, namely lymphoma. Lymphoma is a cancer of the lymphatic system. The lymphatic system makes up a huge part of the body’s network that is tasked with fighting germs that often gain entrance into our body. The system includes the lymph nodes, the spleen, the thymus gland, and the bone marrow. This means that lymphoma can affect all these various tissues and other organs beyond those around the body. Many of us would have experienced swellings around the body at various times, especially at the back of the neck, armpit, groin and under the chin when we have certain types of infections. These lymph nodes are bean-sized collections of lymphocytes and other cells of the immune system throughout the body. Some of them are found inside the chest and in the abdomen, as well as in the pelvis.

Those at the back of the neck would swell often in response to the use of various types of equipment to barb in males or to treat the hair amongst females. A sore throat or a protracted cough could similarly cause similar swellings at the front of the neck and around the jaw; those are lymph nodes. Sometimes, swellings are felt in the groin when there has been an injury to the feet or when there are obvious infections affecting the lower limbs from a variety of causes.

Therefore, lymphoma can start in any part of the body where these tissues are found, and once the cells begin to grow without the necessary biological control, they quickly get out of hand and become what is known as a malignant disease. They can spread to other parts of both the lymphatic system and the body. We discussed the lymphatic system as a part of the circulatory system on this page last August and the understanding of that connection explains a lot of the problems which this group of diseases can cause. Lymphoma is a broad term for cancers that begin in the cells of the lymphatic system. There are two main categories of this disease, and they are named as Hodgkin’s lymphoma (HL) and non-Hodgkin’s lymphoma (NHL).

These two lymphomas develop in different areas of the body with different symptoms and different outcomes. Hodgkin’s lymphoma, which we shall subsequently call HL, has been divided into four different categories by scientists. Non-Hodgkin’s lymphoma, NHL, in contrast, has been divided into two broad classes. Those people who have HL have a larger number of Reed-Steinberg cells, and these are abnormal white blood cells containing more than one nucleus. In patients who have NHL, these kinds of cells are rarely seen. HL is less common than the latter and has a better survival rate of nearly 90 per cent. NHL is much more common, roughly eight times as common, but the survival rate at a five-year point is much less than it is for HL. And although HL can start anywhere in the body, it will most likely start among the lymph nodes in the upper part of the body. This means that the swelling will most likely start in the neck, chest, and armpits. On the other hand, NHL can start almost anywhere around the body where lymph tissues are found. These areas include the stomach, the intestinal tract, the bone marrow, and in an area of the abdominal cavity known as the retroperitoneum.

The retroperitoneum is the area in the back of the abdominal cavity where a membrane lines the walls of that huge space and covers most of the organs within it. Important organs that are found in this area include the kidneys, pancreas, adrenal glands which sit on top of the kidneys, the duodenum which is the first part of the small intestine, the abdominal aorta and the inferior vena cava. There are lymph nodes there as well as nerve roots.

It is therefore an important area where a disease process can also hide away for a long time before detection. Lymphomas constitute the third most common cancer in children after leukaemias and brain tumours. They are, therefore, relatively rare. However, it is important to know that they exist and how they are often present because, in nearly all instances, sick children present late in the hospital due to inadequate attention prior to making the diagnosis. That may partly be due to the fact that the symptoms usually do not appear to be serious. They are rare under the age of five years but are most common between 10 and 20 years of age. However, children between 11 and 15 years are particularly commonly affected. In Nigeria, where many ailments are reported late, even this one is no exception.

While both HL and NHL are far more common in adults, especially in those who are older than 50, it is important to emphasise that their rarity in children should not lure any parent into a false sense of security. In the last one month, one has seen three children aged between 10 and 14 years, stricken with the disease. Not one of them was presented at less than six months from the onset of the illness. Apart from the swelling in those areas we have mentioned above, other features of this illness are on-and-off fever, excessive sweating at night, recurrent cough with or without some shortness of breath, weight loss and frequent complaints of tiredness. There may be a generalised skin rash with associated itching, and there may be changes in toileting habits especially if glands within the abdomen are involved as it’s often seen with NHL. However, in many illnesses caused by viruses or with a disease like tuberculosis, many of these features may also be present, but it is important to see a doctor who would often be able to sift the ones that are likely problematic cases from those that are innocuous. Therefore, going to the hospital with your child, even if they do not appear to be ill, is often the key between survival and early demise.

When this disease is diagnosed early, there will be more treatment options available to the managing doctors. Some of the features we have mentioned above will be fairly obvious and would lead to a speedy diagnosis. Others are more cunning in their presentation and all the affected child may have is a swelling attached to the front wall of the armpit or a swelling in the neck just above the collarbone. Routine full blood count may not yield significant information but sometimes, there will be indications of anaemia and a rise in the total white blood cell count. More usually, the swelling in the identified areas of the body will yield the most reliable information. Therefore, an ultrasound scan of the swelling should be performed followed by an X-ray of the chest and the neck. These will help determine if there are extensions into those areas. In good hospitals with adequate resources, a CT scan of the chest and neck will help resolve all these issues. Once there are indications that the swelling is not an innocent one, preparations should be made to have a biopsy performed. The tissue obtained thereby is sent to a specialised histopathology laboratory for a detailed study under a microscope. This will usually make certain what the diagnosis is. That will guide the treatment plan for the patient.