[Mononeuropathy in chronic lymphatic leukaemia].

Area of Science:

• Oncology
• Neurology
• Pathology

Background:

• Chronic lymphatic leukaemia (CLL) is the most common leukaemia in adults in Western countries.
• Neurological complications of CLL are rare, typically secondary to infections like herpes zoster virus.
• This case explores a novel neurological complication in advanced CLL.

Observation:

• A 71-year-old female with stage IV B-cell CLL, progressing to diffuse large B-cell lymphoma (Richter's syndrome), presented with left peroneal nerve axonotmesis.
• The patient also developed subcutaneous nodules on her left knee.
• MRI revealed diffuse infiltration of subcutaneous tissue and muscles in the left leg.

Findings:

• Biopsy of subcutaneous nodules confirmed lymphoid infiltration by large B-cells.
• The peroneal nerve injury was likely caused by direct infiltration from adjacent soft tissues.
• This suggests direct neoplastic infiltration as a cause of peripheral neuropathy in CLL.

Implications:

• Direct neoplastic infiltration is a potential cause of peripheral neuropathy in chronic lymphatic leukaemia.
• This finding expands the spectrum of known neurological complications associated with CLL.
• Recognizing this rare complication is crucial for accurate diagnosis and management of CLL patients.