Abstract:
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During his clinical practice as a general surgeon in
Uganda, Dr Denis Burkitt was asked in 1957 to see a
paediatric patient with an unusual tumour involving
the jaw and soon after another child with the same
condition was referred to him. The tumour was
rapidly growing and the children died within few
weeks. Burkitt recognized that this unusual condition
was possibly a previously undescribed malignant
tumour. He contacted a large number of hospitals and
institutions in Africa including the senior authors and
asked us to look for this tumour in Sudan. Burkitt
undertook a geographical survey of the incidence
of the disease and found it to be correlated with the
same temperature and rainfall zones as malaria. This
suggested that the tumour might be caused by an
infective agent that was linked with the distribution
of certain insect carriers. In 1958, he published his
first paper on this tumour with his colleagues(1). This
survey is regarded as one of the pioneering studies of
geographical pathology.
At first, the tumour was described as multicentric
sarcoma of the jaw. Later it was found to be a
lymphoma and was named Burkitt’s lymphoma (BL).
It was strongly suspected to be caused by Epstein Barr
virus.
Clinical features and classification
According to the World Health Organization, BL is
classified into three main types: endemic, sporadic
and HIV associated. Endemic BL affects children in
the age group 4-7 years with a male to female ratio of
2:1. Facial bones, particularly the jaws are affected
but other parts of the body such as the thyroid, breast,
kidneys, gastrointestinal tract and ovaries may be
affected. The type described in Uganda and other
African countries is the endemic form(2). There is
evidence that this form is changing in at least some
African countries. Sporadic BL involving mainly
other organs apart from the jaws is described in
Europe, North America and Japan. A form associated
with HIV/AIDS infection has also been described(3).
Lynch and El-Hassan were the first to report Burkitt’s
lymphoma in Sudan under the title multicentric
sarcoma of the jaw4. El-Hassan described another six
cases of BL of the jaws among 113 malignant tumors
in children5.
Nabri described the lymphoma in Equatorial Province
and observed that it usually affects the jaws and other
organs but jaw involvement was most common(6,7).
During the period 1962-73, twenty-nine cases of
Burkitt’s lymphoma were described in Sudan; these
formed 20% of cases of childhood lymphomas(8).
The tumour, mainly of the endemic type, occurred
mainly in the southern and western parts of the Sudan
where malaria is hyperendemic. We now believe that
the pattern of Burkitt’s lymphoma is changing. In
the last seven years in our laboratory, patients with
this lymphoma were found to be of the sporadic type
with involvement of the gastrointestinal tract and
retroperitoneum rather than the jaws. The causes for
this change are at present the subject of investigation.
Central nervous system involvement in BL
One of the complications of BL is involvement of the
central nervous system. This is difficult to treat and
carries a poor prognosis. Of 77 cases of BL in Uganda,
35 patients had neurological changes. These changes
included paraplegia, cranial neuropathy, altered
level of consciousness and malignant pleocytosis.
Paraplegia was a common presenting symptom in BL
and responded well to chemotherapy. The association
of cranial nerve involvement and pleocytosis with
facial bone lesions was believed to be due to the direct
extension of the tumour to the dura and arachnoid.
Intrathecal chemotherapy was effective in reversing
the pleocytosis. Cranial nerve involvement required
systemic chemotherapy( |