Indian Journal of Pathology and Microbiology
Home About us Instructions Submission Subscribe Advertise Contact e-Alerts Ahead Of Print Login 
Users Online: 375
Print this page  Email this page Bookmark this page Small font sizeDefault font sizeIncrease font size

LETTER TO EDITOR Table of Contents   
Year : 2010  |  Volume : 53  |  Issue : 4  |  Page : 891-893
Hairy cell leukemia: An unusual morphology

Department of Pathology, PGIMER and Dr RML Hospital, New Delhi, India

Click here for correspondence address and email

Date of Web Publication27-Oct-2010

How to cite this article:
Sharma A, Buxi G, Marwah S, Yadav RB. Hairy cell leukemia: An unusual morphology. Indian J Pathol Microbiol 2010;53:891-3

How to cite this URL:
Sharma A, Buxi G, Marwah S, Yadav RB. Hairy cell leukemia: An unusual morphology. Indian J Pathol Microbiol [serial online] 2010 [cited 2021 Aug 5];53:891-3. Available from: https://www.ijpmonline.org/text.asp?2010/53/4/891/72045


Hairy cell leukemia (HCL) is a rare indolent chronic lymphoproliferative disorder, which accounts for approximately 2% of all forms of leukemia. [1] We report here an unusual case of HCL presented with splenomegaly and pancytopenia, but cellular bone marrow aspirate showing atypical morphology along with characteristic hyperplasia of mast cells.

A 60-year-old female presented with complaints of low grade fever, breathlessness, cough, weight loss and decreased appetite of 20 days duration. There was no past history suggestive of diabetes mellitus, hypertension, coronary heart disease or pulmonary tuberculosis.

On examination, the patient was conscious, well oriented with no lympadenopathy and sternal tenderness. She had marked pallor with hepatomegaly of 14 cm and splenomegaly of 10 cm. Chest examination revealed crepitations in right infrascapular area.

Routine investigations including serum electrolytes, blood sugar, kidney function test, serum proteins, lipid profile, serum folate and vitamin B12 were within normal limits. Hemogram showed severe pancytopenia.

Serum β2 microglobulin was mildly elevated. Computed tomography (CT) chest revealed irregular, thick-walled, air-filled cavitary lesion in the right lung. Possibility of any infectious lesion was considered. Her sputum was negative for Acid fast bacilli. Serum markers for Hepatitis B and HIV were negative. Patient was given anti tubercular therapy (ATT) empirically for disseminated tuberculosis. Simultaneously, work up for pancytopenia was done.

Bone marrow aspirate was very cellular for age, comprising small to medium sized mononuclear cells [Figure 1]a. These cells had round, slightly indented nuclei with condensed chromatin and scanty pale blue cytoplasm. No mitosis was seen. Scattered normoblast, myelocytes and occasional megakaryocyte were present. Mast cells (2-3/hpf) along with plasma cells were seen [Figure 1]b.
Figure 1: Bone marrow aspirate: (a) cellular smears composed of small to medium sized mononuclear cells with round, slightly indented nuclei with condensed chromatin and scanty pale blue cytoplasm; (b) mast cells (2-3/hpf) are prominent

Click here to view

Bone marrow biopsy showed bony trabeculae enclosing marrow spaces with disturbed topography. The marrow was replaced by mononuclear cells as seen in the aspirate. These cells were well spaced out [Figure 2]a. At some places, very few hematopoietic cells were seen. Mast cells, plasma cells and lymphocytes were also seen.
Figure 2: Bone marrow biopsy: (a) mononuclear cells as seen in the aspirate, which are well spaced out; (b) reticulin stain showed increased fibrosis, seen around individual cells, giving a mesh like appearance

Click here to view

Reticulin stain showed increased fibrosis and these fibers were seen around individual cells, giving a mesh like appearance [Figure 2]b. No hemoparasite or granulomatous lesion was seen.

Immunophenotyping of marrow was done using SS/CD19 gating. Exactly 20% of CD19 positive cells were gated and found positive for B cell associated markers (CD20, CD22, CD79b) along with light chain restriction for anti-lambda antibody. These cells were negative for CD23, CD10, CD5 and T cell markers (CD7, CD3). They expressed characteristic bright positivity for CD11c and moderate positivity for CD103, CD79b and FMC7 [Figure 3].
Figure 3: Immunophenotyping showing dot plots: (a) CD19 vs SS; (b) CD20 positive (bright); (c and d) CD23, CD10 and CD5 negative; (e) CD11c positive (moderate to bright); (f) CD103 positive (moderate); (g) FMC7 and CD79b positive (dim); (h) light chain restriction

Click here to view

Thus, a confirmed diagnosis of HCL was made on immunophenotyping.

Although the natural history of HCL can be extremely variable among patients, they are susceptible to infections by unusual organisms including atypical mycobacterium, which are particularly difficult to diagnose in immunocompromised patients. [2] Being aware of their association with HCL, empiric ATT was given to prolong survival time.

With better appreciation of the wide variability in its clinical and hematological manifestations, bone marrow pathology plays the most important role in the diagnosis of HCL. [3] But as seen in this case, the characteristic morphologic finding of obtaining dry tap on bone marrow aspiration and distinctive "hairy cells" for the diagnosis of HCL, may vary and may be simulated in part by a variety of other hematologic disorders.

Finding of BM mast cell hyperplasia is in accordance with a recent study by Ribatti et al. [4] who reported that mast cells are increased in patients with B cell lymphoproliferative disorders and their density reflects bone marrow angiogenesis.

Immunophenotyping is a highly sensitive and specific method for diagnosis of HCL. [5]

Thus, diagnosis of HCL should always be considered in a patient with pancytopenia and splenomegaly as with the availability of newer therapies, prognosis has markedly improved in patients of HCL.

   References Top

1.Cannon T, Mobarek D, Wegge J, Tabbara AI. Hairy cell leukemia: Current concepts. Cancer Invest 2008;26:860-5.  Back to cited text no. 1
2.Bennett C, Vardiman J, Golomb H. Disseminated atypical mycobacterial infection in patients with hairy cell leukemia. Am J Med 1986;80:891-6.  Back to cited text no. 2
3.Foucar K, Falini B, Catovsky D, Stein H. Hairy cell leukemia. In: Swerdlow SH, Campo E, Harris NL, Jaffe ES, Pileri SA, Stein H, Thiele J, Vardiman JW eds. WHO Classification of tumors of hematopoietic and lymphoid tissues, 4 th edition. IARC Press, Lyons,France 2008;188-90.  Back to cited text no. 3
4.Ribbati D, Crivellato E, Stefano M. Mast cells and angiogenesis in hematological malignancies. Leuk Res 2009;33:876-9.  Back to cited text no. 4
5.Dong HY, Weisberger J, Liu Z, Tugulea S. Immunophenotypic analysis of CD103+ B lymphoproliferative disorders-hairy cell leukemia and its mimics. Am J Pathol 2009;131:586-95.  Back to cited text no. 5

Correspondence Address:
Anjali Sharma
PGIMER and Dr. RML Hospital, New Delhi
Login to access the Email id

Source of Support: None, Conflict of Interest: None

DOI: 10.4103/0377-4929.72045

Rights and Permissions


  [Figure 1], [Figure 2], [Figure 3]


    Similar in PUBMED
   Search Pubmed for
   Search in Google Scholar for
    Email Alert *
    Add to My List *
* Registration required (free)  

    Article Figures

 Article Access Statistics
    PDF Downloaded81    
    Comments [Add]    

Recommend this journal