A 35-year-old Indian man presents with a rapidly enlarging abdominal mass and elevated LDH. Biopsy shows a highly proliferative lymphoma with a 'starry sky' pattern and t(8;14) translocation. What is the most common site of presentation for this lymphoma?

Explanation

## Burkitt Lymphoma: Most Common Site **Key Point:** Burkitt lymphoma most commonly presents in the abdomen, particularly the ileocecal region, accounting for ~50% of presentations. This is especially true in endemic (African) and sporadic (Western/Indian) forms. ## Clinical Presentation by Geographic Form | Form | Most Common Site | Frequency | Age | |------|------------------|-----------|-----| | **Endemic (African)** | Jaw (mandible) | 50–80% | Children 4–7 years | | **Sporadic (Western/Indian)** | Abdomen (ileocecal) | 50–60% | Adolescents & young adults | | **Immunodeficiency-associated** | CNS, GI, bone marrow | Variable | Immunocompromised | **High-Yield:** In India and Western countries, the *sporadic* form predominates, and abdominal presentation (especially ileocecal region) is most common. ## Why Ileocecal Region? 1. **Lymphoid tissue density** — Peyer's patches and gut-associated lymphoid tissue (GALT) are abundant in terminal ileum and cecum 2. **Rapid proliferation** — Burkitt is the fastest-growing human malignancy; GI lymphoid tissue provides fertile ground 3. **Clinical consequences** — Presents with abdominal pain, obstruction, bleeding, or perforation ## Pathognomonic Features of Burkitt **Mnemonic: "BURKITT = Blast-like, Uniform, Rapid, Ki-67 very high, Immunoblastic, Translocation t(8;14), Tiny nucleoli"** - **Histology:** "Starry sky" pattern (tingible body macrophages amid blasts) - **Immunophenotype:** CD20+, CD10+, BCL6+; BCL2− (unlike follicular lymphoma) - **Cytogenetics:** t(8;14)(q24;q32) — *MYC* translocation to immunoglobulin heavy chain locus - **Proliferation:** Ki-67 ~100% (nearly all cells in cycle) - **LDH:** Markedly elevated (reflects tumor burden) ## Clinical Pearl: Abdominal Burkitt **Warning:** Abdominal Burkitt can present with acute surgical abdomen (perforation, obstruction) and may be mistaken for appendicitis or intussusception. Rapid diagnosis and chemotherapy are essential — this is a medical emergency despite being highly chemosensitive. ## Sites in Order of Frequency (Sporadic Form) 1. **Abdomen** (ileocecal) — 50–60% 2. **Peripheral nodes** (inguinal, axillary) — 20–30% 3. **Mediastinum** — 10–15% 4. **CNS** — 5–10% (at presentation or relapse)