FRCPath Haem Part 1 MCQs-Oncology 472

Aug 13

1 min read

A 64-year-old man presents with a 3-month history of progressive fatigue, night sweats and weight loss of 9 kg. Examination reveals generalized lymphadenopathy and moderate splenomegaly.

FBC:

Parameter	Result
Hb	96 g/L
WBC	58 × 10⁹/L
Neutrophils	8.2 × 10⁹/L
Lymphocytes	46 × 10⁹/L
Platelets	112 × 10⁹/L

The cells are medium-to-large, with a relatively high nuclear-to-cytoplasmic ratio. Nuclei are irregular and occasionally cleaved. The chromatin is moderately condensed but some cells have dispersed chromatin. A proportion of the cells have blastoid morphology, with round nuclei, fine chromatin and inconspicuous nucleoli. Bone marrow aspirate demonstrates extensive infiltration by the abnormal lymphoid population.

Flow cytometry demonstrates a mature B-cell population:

CD19: positive
CD20: strong
CD22: positive
Light-chain restricted
CD5: positive
CD10: negative
FMC7: positive

Which of the following is the most likely additional immunophenotype?

A. CD10+, BCL6+, BCL2+, cyclin D1−

B. Cyclin D1+, SOX11+, BCL6−, CD10−

C. CD23+, LEF1+, cyclin D1−, SOX11−

D. CD10+, BCL6+, MUM1+, cyclin D1+

E. CD138+, MUM1+, CD20−, PAX5−

1 Comment

adwaanhemay

Aug 14

Answer

Most likely diagnosis:

Mantle cell lymphoma (MCL), blastoid variant

Explanation

This is a deliberately difficult case because the blastoid morphology and high white-cell count can make the diagnosis look like acute lymphoblastic leukaemia, Burkitt lymphoma, transformed CLL or another high-grade B-cell lymphoma.

The key is to integrate:

Morphology + mature B-cell phenotype + CD5 positivity + CD23 negativity + bright surface Ig + FMC7 positivity

This strongly points towards mantle cell lymphoma.

1. Morphological clues

Classical MCL usually consists of:

Small-to-medium lymphoid cells
Irregular/angulated nuclear contours
Condensed chromatin
Scant cytoplasm

However, MCL can have blastoid or pleomorphic variants.

Blastoid MCL

The blastoid variant contains:

Larger cells
Fine chromatin
Increased mitotic activity
Blast-like appearance

1 Comment

Answer

B. Cyclin D1+, SOX11+, BCL6−, CD10−

Most likely diagnosis:

Mantle cell lymphoma (MCL), blastoid variant

Explanation

This is a deliberately difficult case because the blastoid morphology and high white-cell count can make the diagnosis look like acute lymphoblastic leukaemia, Burkitt lymphoma, transformed CLL or another high-grade B-cell lymphoma.

The key is to integrate:

Morphology + mature B-cell phenotype + CD5 positivity + CD23 negativity + bright surface Ig + FMC7 positivity

This strongly points towards mantle cell lymphoma.

1. Morphological clues

Classical MCL usually consists of:

Small-to-medium lymphoid cells

Irregular/angulated nuclear contours

Condensed chromatin

Scant cytoplasm

However, MCL can have blastoid or pleomorphic variants.

Blastoid MCL

The blastoid variant contains:

Larger cells

Fine chromatin

Increased mitotic activity

Blast-like appearance