A 58-year-old man presents with fatigue and abdominal fullness. Examination shows massive splenomegaly. CBC reveals pancytopenia with absolute monocytopenia. Bone marrow aspiration yields a dry tap; biopsy shows diffuse interstitial infiltration by mononuclear cells with abundant pale cytoplasm giving a fried egg appearance. The cells are tartrate-resistant acid phosphatase positive and express CD11c, CD25 and CD103. Best initial treatment?

• A CHOP chemotherapy
• B Splenectomy
• C Hydroxyurea
• D Cladribine ✓

Explanation

This is classic hairy cell leukaemia: pancytopenia with monocytopenia, massive splenomegaly, dry tap, fried egg histology, TRAP positivity and coexpression of CD11c, CD25 and CD103. Single-agent purine analogue therapy with cladribine produces durable complete remissions in most patients and is first line. Splenectomy is now reserved for selected refractory cases, hydroxyurea does not eliminate the clone, and CHOP is a lymphoma regimen.

Reference: Harrison's Principles of Internal Medicine, 21st ed.

High-yield for: NEET PGINI-CETNExTFMGEUSMLEPLABMRCP

Written and medically reviewed by the StethoPrep medical team.