Unusual complication and successful high-dose chemotherapy treatment of advanced Burkitt’s lymphoma in an adult HIV-positive patient

Adult Burkitt’s lymphoma emerged as an AIDS-defining condition in the 1980s. We describe a case of HIV-associated adult Burkitt’s lymphoma diagnosed and treated with high-dose chemotherapy in our institution, complicated by unusual bilateral renal vein tumour thrombi and tumour lysis syndrome. We believe this unique case highlights the need for early recognition of current and potential complications on staging computed tomography imaging, as well as successful use of a high-dose chemotherapy regimen.


Introduction
Burkitt's lymphoma is a highly proliferative B-cell neoplasia first described as a childhood illness endemic to malaria areas of Africa. Following the emergence of HIV in the 1980s, its significance as an AIDS-defining condition was soon recognised with a far more aggressive natural history, and its significance as an AIDS-defining condition was demonstrated.
HIV-associated lymphomas remain a significant cause of morbidity and mortality, especially within sub-Saharan Africa, and familiarity with imaging findings is essential in suggesting the initial diagnosis, identifying complications and assessing response to treatment. We present a case of adult Burkitt's lymphoma with advanced disease.

Case report
A 49-year-old man presented near cardiac-arrest with a 4-week history of weight loss, night sweats, back pain and difficulty walking.
A new HIV-1 diagnosis was made (CD4 lymphocyte count 3 cells/µL, viral load 912 376 copies/mL). Epstein-Barr viral titres were 21 620 500 copies/mL. Computed tomography (CT) suggested Burkitt's lymphoma with disease affecting the lungs, heart ( Figure 2), sternum, liver, vertebrae and kidneys with bilateral renal vein tumour thrombi. Biopsy of the sternal mass demonstrated diffuse lymphoid infiltrates of skeletal muscle in a starry sky pattern, in keeping with Burkitt's lymphoma.
The patient was commenced on antiretroviral therapy including Descovy and Dolutegravir, with a Rituximab-CODOX-M/IVAC chemotherapy regimen. 1 His initial management was complicated by tumour lysis syndrome, 2 pseudomonas bacteraemia and cytomegalovirus infection of the gastrointestinal tract, all successfully treated. Subsequent CT imaging revealed an excellent treatment response, regression of extensive hepatic and renal infiltration and resolution of bilateral renal vein tumour thrombi, allowing anticoagulation to be discontinued.

Discussion
First reported in 1958, Burkitt's lymphoma can be usefully subdivided into endemic, sporadic (without geographical limitation) and immunodeficiency-associated. Predominantly a disease of Adult Burkitt's lymphoma emerged as an AIDS-defining condition in the 1980s. We describe a case of HIV-associated adult Burkitt's lymphoma diagnosed and treated with high-dose chemotherapy in our institution, complicated by unusual bilateral renal vein tumour thrombi and tumour lysis syndrome. We believe this unique case highlights the need for early recognition of current and potential complications on staging computed tomography imaging, as well as successful use of a high-dose chemotherapy regimen.

Unusual complication and successful high-dose chemotherapy treatment of advanced Burkitt's lymphoma in an adult HIV-positive patient
Read online: Bilateral renal vein tumour thrombosis is an uncommon complication, not typically seen in lymphoma, necessitating anticoagulation ( Figure 4). 5,6 CT confirmed resolution, allowing a return to thromboprophylaxis alone.
Disease confined to the abdomen is described in 50%, 7 usually hepatosplenomegaly which may be observed on ultrasound.
Abdominal and pelvic CT is beneficial for further characterisation and better demonstrates potential involvement of the distal small bowel, caecum and appendix. 8 Involvement of the central nervous system heralds a poor prognosis (5-year survival drops to < 30%); our patient underwent CT and magnetic resonance imaging (MRI) brain which did not demonstrate CNS disease. Bilateral cavernous sinus involvement has been described in an immunocompetent individual with confirmed Burkett's lymphoma, 9 diagnosed using CT and multi-parametric MRI; although the patient responded to first line cyclophosphamide-vincristine chemotherapy, CNS disease recurred and the patient died after 11 months.
Involvement of the distal urinary tract, testicular involvement, pancreatic disease and jaw involvement has been described in adults. Positron emission tomography-computed tomography (PET-CT) has been utilised to identify additional sites of disease, with a low false negative rate. However, a high false positive rate has been noticed within the immunosuppressed population attributed to concurrent opportunistic infections.

Conclusion
We