What is the diagnosis and treatment for a child presenting with rapidly enlarging jaw and facial bone swelling, firm non-tender masses in the maxillary and mandibular regions, and cervical lymphadenopathy?

Diagnosis: Endemic Burkitt Lymphoma

This 7-year-old boy from rural Africa with rapidly enlarging jaw masses, cervical lymphadenopathy, and firm non-tender maxillary/mandibular involvement has endemic Burkitt lymphoma until proven otherwise, and requires immediate initiation of intensive combination chemotherapy after confirming the diagnosis with biopsy showing characteristic immunohistochemistry (CD20+, CD10+, Ki-67 >95%) and MYC translocation. 1, 2, 3

Clinical Recognition and Geographic Context

• Endemic Burkitt lymphoma is the classic presentation in African children from malaria-endemic regions, characteristically involving jaw and facial bones as the primary site 3
• The rapidly progressive nature (developing over weeks) with firm, non-tender masses is pathognomonic for this highly aggressive B-cell lymphoma with an extremely short tumor doubling time 2, 4, 5
• This differs from sporadic Burkitt lymphoma (seen in Western countries) which typically presents with abdominal masses rather than jaw involvement 3

Diagnostic Confirmation from Biopsy

The biopsy must demonstrate specific features to confirm Burkitt lymphoma:

• Histology: Intermediate-sized lymphoid cells with basophilic cytoplasm and characteristic "starry sky" appearance (due to tingible body macrophages phagocytosing apoptotic tumor cells) 1, 5
• Immunohistochemistry panel (mandatory): CD20+, CD10+, surface immunoglobulin+, with Ki-67 proliferation index >95% (nearly 100% in classic cases) 1, 5
• Genetic studies: MYC translocation t(8;14) or variants t(2;8) or t(8;22) involving immunoglobulin genes 2, 3, 5
• The immunohistochemistry must include CD45, CD20, and CD3 as minimal requirements 6

Critical Staging Workup Before Treatment

Before initiating chemotherapy, complete the following urgently:

• Complete blood count with differential to assess for bone marrow involvement (which would classify as stage IV or B-cell ALL if >25% blasts) 1, 7
• Lactate dehydrogenase (LDH) level—elevated LDH >1000 IU/L indicates worse prognosis and higher tumor burden 6, 7
• CT chest and abdomen to evaluate for extranodal disease and assess full disease extent 6
• Bone marrow aspirate and biopsy to determine marrow involvement 6
• Lumbar puncture with CSF analysis for CNS involvement (critical as CNS disease dramatically worsens prognosis) 6, 2, 7
• Renal function and uric acid to assess tumor lysis syndrome risk before starting chemotherapy 6

Immediate Pre-Treatment Management

Tumor lysis syndrome prophylaxis is mandatory given the rapid cell turnover and high chemosensitivity:

• Aggressive IV hydration (2-3 times maintenance) 2
• Allopurinol or rasburicase to prevent hyperuricemia 2
• Frequent monitoring of electrolytes, phosphate, calcium, uric acid, and renal function 2

Treatment: Intensive Combination Chemotherapy

High-intensity, short-duration combination chemotherapy is the standard of care for Burkitt lymphoma in children:

• For stage III disease (localized but unresectable, which jaw involvement typically represents): Intensive multi-agent regimens achieve 80-85% long-term disease-free survival 7
• Regimens include fractionated high-dose cyclophosphamide (300 mg/m² every 12 hours × 6 doses), doxorubicin, vincristine, with high-dose methotrexate and cytarabine in subsequent cycles 7
• Intrathecal chemotherapy (methotrexate and cytarabine) is mandatory for CNS prophylaxis even without documented CNS involvement 7
• Treatment duration is approximately 24 weeks with 4-6 cycles 7

Prognosis Based on Stage

• Stage III (localized jaw/facial involvement without CNS or marrow): 81% actuarial disease-free survival at 2 years with intensive chemotherapy 7
• Stage IV or CNS involvement: Much worse prognosis with only 20% long-term survival, representing the major treatment challenge 2, 7
• Initial LDH >1000 IU/L is an independent poor prognostic factor 7

Critical Pitfalls to Avoid

• Do not delay treatment for extensive staging—Burkitt lymphoma doubles in size every 24-48 hours, and delays can lead to tumor lysis syndrome or progression to CNS disease 2, 4
• Do not use standard CHOP chemotherapy (appropriate for diffuse large B-cell lymphoma)—Burkitt lymphoma requires much more intensive regimens with CNS prophylaxis 6, 2
• Do not underestimate myelosuppression risk—expect profound neutropenia requiring growth factor support and aggressive infection management 7
• Do not miss CNS involvement—failure to perform lumbar puncture and provide adequate CNS prophylaxis is a common cause of relapse 2, 7

Differential Diagnosis Considerations

While the clinical presentation strongly suggests Burkitt lymphoma, the biopsy must exclude:

• Diffuse large B-cell lymphoma: Larger cells, variable nuclear contours, Ki-67 typically 40-70% (not >95%), lacks starry sky pattern 1, 5
• B-lymphoblastic leukemia/lymphoma: TdT+, CD10+ but lacks surface immunoglobulin, different clinical behavior 5
• Hodgkin lymphoma: Would show Reed-Sternberg cells, CD15+/CD30+, not the monomorphic intermediate-sized cells of Burkitt 6, 1