Lymphoma — recognition and initial management OSCE station (NEET-PG/INICET)

Candidate instructions

You are the doctor in the emergency department. A 19-year-old man has a rapidly enlarging abdominal mass, vomiting, fever and weight loss, with abnormal electrolytes and kidney function. You have 8 minutes to assess and begin managing him, and 2 minutes for examiner questions.

Investigations provided: white-cell count 28 x 10^9/L, haemoglobin 95 g/L, platelets 90 x 10^9/L, potassium 6.2 mmol/L, phosphate 2.1 mmol/L, corrected calcium 1.8 mmol/L, urate 560 micromol/L, creatinine 180 micromol/L, LDH raised. A CT abdomen shows a large ileocaecal/abdominal mass with bulky mesenteric nodes.

Candidate tasks

1. Take a focused, rapid history including symptom time-course, B symptoms (fever, night sweats, weight loss), HIV risk, prior haematological disease and family history.
2. Perform a focused general examination (nodes all groups, abdominal mass and organomegaly, airway, perfusion, fluid status, neurological status).
3. Recognise the life-threatening emergency in the blood results and state your immediate management.
4. State the definitive diagnostic procedure and the staging investigations, with rationale.
5. Communicate your plan, disposition and the urgency clearly to the examiner.

Examiner checklist (mark each as done / partial / not done)

• Recognises this as an aggressive non-Hodgkin lymphoma (rapidly growing abdominal/ileocaecal mass with bulky nodes, B symptoms, raised LDH) — Burkitt-type in a young adult — and triggers an urgent haematology/oncology referral.^[1][2]
• Identifies tumour lysis syndrome in the blood results — hyperkalaemia (6.2), hyperphosphataemia (2.1), hyperuricaemia (560), hypocalcaemia and AKI (creatinine 180) — and acts immediately.^[1]
• Starts immediate management of tumour lysis: aggressive IV hydration, rasburicase 0.2 mg/kg IV (high tumour burden; avoid in G6PD deficiency), cardiac monitoring for hyperkalaemia, and treatment of hyperkalaemia (calcium gluconate for cardiac protection, insulin-dextrose, consideration of dialysis if refractory).^[1]
• States that the definitive diagnosis requires an excisional biopsy (NOT FNA) of a node or the mass, sent for histology, immunohistochemistry, flow cytometry and cytogenetics/FISH for t(8;14) MYC.^[1][3]
• Orders the correct staging and baseline workup: FDG PET-CT, bone marrow biopsy, full blood count and film, LDH, beta-2 microglobulin, ESR, U&E, LFT, HIV and hepatitis B/C serology (influence treatment and rituximab/hepatitis-B reactivation risk).^[2][3]
• Recognises and asks about the other lymphoma emergencies — a mediastinal mass/SVC syndrome (airway, steroids, avoid sedation) and epidural spinal cord compression (IV dexamethasone) — even if not present here.
• Plans supportive care and disposition: admit to haematology/oncology (or high-dependency given the metabolic derangement), cardiac monitoring, renal/nephrology input if dialysis is likely, and fertility counselling before chemotherapy.
• Communicates the diagnosis, the tumour-lysis emergency, the diagnostic and staging plan, and a clear disposition.

Model answer / expected standard

This is an aggressive non-Hodgkin lymphoma — a Burkitt-type presentation in a young adult (rapidly enlarging abdominal/ileocaecal mass, bulky nodes, B symptoms, very high LDH, Ki67 near 100 percent) — and it is already complicated by tumour lysis syndrome (hyperkalaemia 6.2, hyperphosphataemia 2.1, hyperuricaemia 560, hypocalcaemia, AKI). The immediate priority is to treat the tumour lysis: aggressive IV hydration, rasburicase 0.2 mg/kg IV, cardiac monitoring and treatment of hyperkalaemia (calcium gluconate, insulin-dextrose, dialysis if refractory), and close monitoring of potassium, phosphate, calcium, creatinine and urate.^[1]

In parallel, secure the diagnosis with an excisional biopsy (not FNA) of a node or the mass for histology, immunohistochemistry, flow cytometry and FISH for t(8;14) MYC, and stage with FDG PET-CT plus bone marrow biopsy and the baseline blood panel including HIV and hepatitis B/C. Definitive treatment is intensive short-course chemotherapy with CNS prophylaxis (e.g. CODOX-M/IVAC or dose-adjusted EPOCH-R) under haematology, with continued tumour-lysis prophylaxis. Disposition is admission under haematology/oncology with high-dependency support for the metabolic derangement, with renal/nephrology input for possible dialysis and fertility preservation counselling before chemotherapy.^[1][2][3]

Common errors

• Missing tumour lysis syndrome in the electrolytes, or attributing the AKI and hyperkalaemia to dehydration alone — delays rasburicase and hydration.
• Treating the hyperkalaemia but forgetting rasburicase (allopurinol is insufficient for high-burden established tumour lysis).
• Relying on fine-needle aspiration for diagnosis — it cannot subtype lymphoma; an excisional biopsy is required.
• Failing to check HIV and hepatitis B/C before starting rituximab-containing chemotherapy (hepatitis-B reactivation risk).
• Not recognising the Burkitt subtype and treating it with standard R-CHOP alone — Burkitt needs intensive short-course chemo with CNS prophylaxis.
• Forgetting fertility preservation counselling before chemotherapy in a young patient.

References

The station is built on the Lopez Nature Reviews Disease Primers primer of Burkitt lymphoma, the Sehn-Salles review of diffuse large B-cell lymphoma, and the Cheson Lugano classification for staging and response assessment.^[1][2][3]

References3ShowHide

1. [1]López C, Burkhardt B, Chan JKC, et al. Burkitt lymphoma. Nature Reviews Disease Primers, 2022.PMID 36522349
2. [2]Sehn LH, Salles G. Diffuse large B-cell lymphoma. New England Journal of Medicine, 2021.PMID 33657296
3. [3]Cheson BD, Fisher RI, Barrington SF, et al. Recommendations for initial evaluation, staging, and response assessment of Hodgkin and non-Hodgkin lymphoma: the Lugano classification. Journal of Clinical Oncology, 2014.PMID 25113753