A 68-year-old man with slowly progressive lymphocytosis, lymphadenopathy, and splenomegaly has a WBC of 85 × 10⁹/L with mature-looking small lymphocytes. Flow cytometry shows CD5+, CD19+, CD23+, CD20 dim+, and surface Ig dim+. The cytogenetic finding associated with the BEST prognosis in CLL is:
- A Trisomy 12 — intermediate prognosis
- B Isolated deletion 13q14 (del13q) — associated with indolent course and longest survival ✓
- C Deletion 17p13 (TP53 deletion) — associated with poorest prognosis and resistance to chemoimmunotherapy
- D Deletion 11q22 (ATM deletion) — associated with bulky lymphadenopathy and poor prognosis
Correct answer: B. Isolated deletion 13q14 (del13q) — associated with indolent course and longest survival
Explanation
CLL cytogenetics by FISH stratifies prognosis: del13q14 (miR-15a/16-1 locus) as the sole abnormality predicts the most favourable outcome with median survival >10 years; trisomy 12 is intermediate; del11q22 (ATM) and del17p13 (TP53) carry poor prognosis, with del17p being associated with resistance to standard chemoimmunotherapy (FC-R regimen). Novel agents (ibrutinib, venetoclax) have partially overcome del17p resistance.
Reference: Robbins & Cotran Pathologic Basis of Disease, 10th ed.
High-yield for: NEET PGINI-CETNExTFMGEUSMLEPLABMRCP
Written and medically reviewed by the StethoPrep medical team.