SEER is an authoritative source of information on cancer incidence and survival in the United States. SEER currently collects and publishes cancer incidence and survival data from population-based cancer registries covering approximately 28 percent of the U.S. population.
A rare type of leukemia in which abnormal B-lymphocytes are present in the bone marrow, spleen and peripheral blood. When viewed under a microscope, these cells appear to be covered with tiny hair-like projections. Neoplasm in bone marrow and peripheral blood composed of small B lymphoid cells with oval nuclei and abundant cytoplasm with hairy projections, diffusely infiltrating bone marrow and splenic red pulp.
Do NOT use this code for hairy cell leukemia variant (See 9591/3). When HCL is diagnosed in people in their 20's, it is hairy cell leukemia variant (9591/3)
HCL is a rare disease which predominantly occurs in middle-age to elderly adults. HCL is exceptionally uncommon in children. The diagnosis is best made on bone marrow. HCL infiltrates are found in the red pulp of the spleen. The white pulp is typically atrophic. The liver may show infiltrates of hairy cells, predominantly in the sinusoids. Lymph node infiltration may occur especially in advanced disease.
Definitive Diagnostic Methods
Bone marrow biopsy
Coexpression of multiple clonally related Ig-isotypes