The most common cancers
Kaposi''s sarcoma is a malignant cancer, related to the action of a herpesviruses virus, HHV-8, also known as KSHV (Kaposi''s Sarcoma-Associated Herpes Virus).
It produces a proliferation of papules, which subsequently evolve into plaques and then into blue/red nodules that affect the skin.
There are four types of Kaposi''s sarcoma:
- The classic form, sporadic, affecting older people in the Mediterranean area and
Europe and men in Sub-Saharan Africa.
- The African endemic form, which affects mostly children and young people.
- The iatrogenic form, induced by treatment with drugs resulting in immunosuppression and consequently the lowering of the immune system
- The epidemic form that is associated with HIV, that particularly affects the sub-
Saharan African region. It is less conventional in Europe and the USA, where it is treated with antiretroviral medicines.
- Kaposi''s sarcoma occurred only occasionally before the AIDS epidemic, mostly in
East and Central Africa. After the 1980s, the growth rate of this cancer increased quickly (57,000 new cases each year) to become one of the most important and widespread cancers.
Liver cancer affects around 8% of the African population, with an average of about 200,000 deaths each year. Hepatitis B virus and hepatitis C are very high risk factors for liver cancer. The vaccine against hepatitis B has been available since the 80s and today it is considered safe and effective in the prevention of hepatocellular carcinoma. However, data recorded by WHO show that in sub-Saharan Africa, less than 7% of people receive this vaccination.
Being a form of cancer often asymptomatic, liver cancer is very difficult to treat. Where the diagnosis is realized in a very late stage, the incidence of the disease is almost similar to that of mortality.
Liver cancer has a very low incidence in Western countries (in Italy 10 cases per 100,000), but is as high as 110 cases per 100,000 in some African countries such as Mozambique, where it is more popular due to the presence of many individuals infected with hepatitis B.
Prostate cancer is the third most common cancer in African men. It develops most often in men above 65 years of age, consequently it is more frequent those African countries where life expectancy exceeds 60 years. Among the major risk factors are genetics and diet. Unfortunately, it is an undetectable disease.
Among women in sub-Saharan Africa, cancer of the cervix, or neck of the uterus, is the most common type of cancer, and it affects approximately 12% of the population. Infection by the human papillomavirus (HPV) is the main risk factor for its occurrence.
At present, two vaccines exist for HPV, and in Europe and the USA vaccination programs against this virus started in 2007. The campaign started in Italy in March 2008, offering free vaccinations to girls aged 11 to 12 years.
In Africa the introduction of the vaccination against HPV is still almost impossible, because of its high price, that can often be the same as the annual per capita income.
Other risk factors can include: high number of pregnancies, multiple sexual partners, first intercourse at a young age, smoking, use of oral contraceptives, or weakening of the immune system. Generally, cancer of the cervix is asymptomatic, but the appropriate prevention and a proper diagnosis by a pelvic exam, pap smear or colposcopy can minimize the risk of contracting the disease.
In the world and in women, breast cancer is the most common form of cancer; in Africa it is the second most common cancer.
There are several risk factors: hereditary (family), hormonal (use of estrogen and progestin), reproductive (primiparous or nulliparous women, early menarche or late menopause), social (type of diet, alcohol consumption, obesity), environmental (radiation exposure), race (white people are more vulnerable than black people).
Breast cancer is one of the most preventable cancers. Although not always feasible in Africa, adequate screening and early diagnosis can greatly reduce the mortality rate.
In equatorial Africa, Burkitt''s lymphoma is the most common form of cancer in children. Here the disease is present in a endemic variant; It is associated with the presence of malaria and the HIV and the Epstein-Barr viruses.
Lymphoma is characterized by a deformation of the mandible. It mostly affects children from 0 to 14 years, and particularly boys between five and nine years old. In the case of HIV-positive children – newborn to 10 years – the possibility of developing Burkitt''s lymphoma is high.
Lymphoma belongs to the so-called forms of non-Hodgkin''s lymphoma, it attacks the B cells and may affect not only the mandible but also other parts of the body.In the western world Burkitt''s lymphoma is very rare and is effectively treated; for example,
it is estimated that in the United States no more than 300 new cases per year are diagnosed. In equatorial Africa the disease is much more frequent and the mortality rate is still very high.