In simple words: Hairy cell leukemia is a rare blood cancer where certain white blood cells don't work correctly. These abnormal cells build up in the bone marrow, causing problems with normal blood cell production. This can lead to symptoms like fatigue, infections, easy bruising, and an enlarged spleen.

Hairy cell leukemia is a rare type of chronic lymphoid leukemia characterized by the presence of abnormal B lymphocytes with hair-like projections. These abnormal cells accumulate in the bone marrow, hindering normal blood cell production.It primarily affects middle-aged and older men.

Example 1: A 55-year-old male presents with fatigue, recurrent infections, and an enlarged spleen.A CBC reveals pancytopenia, and a bone marrow biopsy confirms the diagnosis of hairy cell leukemia., A 60-year-old female is incidentally found to have hairy cell leukemia during a routine check-up. She is asymptomatic, and watchful waiting is recommended., A 45-year-old male with hairy cell leukemia experiences relapse after initial treatment with cladribine.He is started on a targeted therapy regimen.

Documentation should include complete blood count (CBC) with differential, peripheral blood smear, bone marrow biopsy results, and imaging studies. The BRAF V600E mutation status should also be documented.