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HAIRY CELL LEUKAEMIA (HCL) IS A RARE chronic B lymphoproliferative disorder rep-resenting 2% of all leukaemias.1 The name
HCL was coined in 1964 by Shrek and Donnelly.2 It 
was first identified as a clinical entity in 1958 and was
known as leukaemic reticuloendotheliosis.2 At present 
the hairy cell has not been identified to have a known
normal counterpart in lymphocyte ontogeny. We de-
scribe four cases of hairy cell leukaemia, the first to be

reported from the Sultanate of Oman.

 C A S E  1 

An Omani male, 61 years of age, presented with recur-
rent anaemia to another hospital in Muscat. He was 
transfusion dependent and admitted to the Royal Hos-
pital with fever and pancytopaenia and found to have a 
splenomegaly of 8cm and  hepatomegaly of  6cm. His 
complete blood count (CBC) showed: Hb% - 3.2G/dL, 

Hairy Cell Leukaemia in Oman
Four cases

*Arundathi Kurukulasuriya, Asia Al-Rashdi, Muhanna Al-Muslahi 

SULTAN QABOOS UNIVERSITY MEDICAL JOURNAL 
NOVEMBER 2008, VOLUME 8, ISSUE 3, P. 333-338
SULTAN QABOOS UNIVERSITY©
SUBMITTED - 12TH APRIL 2008
ACCEPTED - 22ND AUGUST 2008

C A S E  R E P O R T

عمان سلطنة في الشعرية اخلاليا دَّم ابْيِضاضُ
أربع حاالت

املصلحي مهنا الراشدي، اسيا كوروكوالسوريا،  ارونداثي

لَة امِ الشَّ رَيَّاتِ الكُ قِلَّةُ العمر. أواسط الذكور في يصيب ما غالبا ومزمن نادر نَسيلِيّ يّ ْفِ ملِّ تَّكاثُريُ اضطراب هو الشعرية اخلاليا دَّم ابْيِضاضُ  امللخص:
غزير سايتوبالزم الليمفاوية ذو اخلاليا ــاف بواسطة اكتش التشخيص يتم ــارا. انتش ــريرية الس العالمات أكثر من ــيم اجلس حال الطِّ مُ خُّ وتَضَ الدم في
جاف. بزل إلى في الغالب العظم تؤدي نقي افَة رُشَ أخذت اسمها. هنا ومن ونقي العظم، ة الدم احمليطي في لُطاخَ شعرية أطراف ــكل ش ــر على ينتش
 CD103, CD25, FMC7, CD11c منطيا  يكون ــيابي االنس الكريات ْرَبَة)، وعد َا) ــل سَ العَ قُرْصُ ــبه مظهر تش خاصة صفات لها ب ِنْقَ امل ةٌ زْعَ خَ
لُ بالعامِ ئات البورين املتبوع ضاهِ CD19, CD20, CD79a . مُ الكالسيكية الليمفاوية واصمات اخلاليا مع  اخلفيفة ايجابية كابَّا غاما أو لَةُ لْسِ وسِّ
املرض من ــنوات خالية س ــر عش ــجيل أمكن تس احلالي. في الوقت األمثل العالج هو احلمى عن الناجت الَت دِ العَ لعالج قِلَّةُ احملببة رات مَ عْ ــتَ سْ للمُ ُنَبِّهُ امل
املذكور املرض من حاالت أربع هنا ندرج هذا املرض. لعالج واعدة نتائج أيضا CD22أظهر CD20 و  ملضاد التجريبي االستعمال العالج. ذلك بواسطة

سلطنة عمان. في املستشفى السلطاني مبسقط في سنتني خالل شخصت

عمان. سلطنة حاالت، ، تقرير اللمفي اضطراب التكاثر ، دَّم اخلاليا الشعرية الكلمات: ابْيِضاضُ مفتاح

Department of Haematology & Blood Transfusion, Royal Hospital, Muscat, Sultanate of Oman

*To whom correspondence should be addressed. Email: arundathi54@yahoo.com

ABSTRACT Hairy cell leukaemia (HCL) is a rare, clonal, chronic lymphoproliferative disorder commonly seen in males in the middle 
years of life. Pancytopaenia with moderate to massive splenomegaly is the most common clinical presentation. Diagnosis is made on 
detecting the lymphocytes with abundant cytoplasm which spread into hair-like processes on peripheral blood and bone marrow 
smears, thus giving the name, “hairy cell leukaemia”. The bone marrow aspirate is frequently a dry tap. The trephine biopsy has the
characteristic features of a honey comb appearance and flow cytometry is typically CD03, CD25, FMC7, CDc, gamma or kappa light
chain positive with the classic B lymphocyte markers CD9, CD20, CD79a. Purine analogues followed by granulocyte-colony stimu-
lating factor (G-CSF) to manage the febrile neutropenia is currently the treatment of choice. A 0 year disease free survival is recorded 
with these management strategies. Experimental use of anti CD20 and CD22 has also shown promising results in the treatment of this 
disease. We report four cases of HCL diagnosed in a span of two years at the Royal Hospital, Muscat, Oman. 

Key words:: Hairy cell leukaemia; Lymphoproliferative disorder; Case report; Oman.



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white blood cells (WBC) - 0.8 x 109/L, absolute neu-
trophil count (ANC) 0.3 x 109/L, platelets - 48 x 10 
9/L. Renal and liver function tests were normal other 
than for a low serum albumin. The blood picture con-
firmed the presence of pancytopaenia with no blast
cells or dysplastic changes. He was resuscitated with 
blood transfusion and intravenous antibiotics. Nursed 
in isolation, the bone marrow aspirate was performed 
once his condition stabilised.

The bone marrow aspirate and trephine biopsy
showed hairy cells. The cytochemistry was positive
with tartrate resistent acid phosphatase (TRAP).

The immunohistochemistry on the trephine biop-
sy showed the lymphocytes were positive for CD20, 
CD79a and DBA 44.

Flow cytometry (FCM) on the bone marrow as-
pirate was positive for CD19, CD20, CD22, CD25, 
CD103, CD11c, FMC7 and kappa light chain and neg-
ative for CD3, CD5, CD7, CD10, CD23, CD38.

The diagnosis of hairy cell leukaemia was estab-
lished, but the patient refused intravenous chemo-
therapy and received three mega units of interferon 
alpha subcutaneously thrice a week for six months. 
He achieved a complete haematological response and 
his CBC remained stable six months after cessation of 
therapy.

C A S E  2 

An Omani male, aged 62 years, was referred from 
another hospital for pancytopaenia, diagnosed with 
myelodysplasia (MDS) and treated with blood trans-
fusions, erythropoietin and granulyte-colony stimu-
lating factor (G-CSF) without significant response. He
was admitted to the Royal Hospital with fever, malena, 
haematemesis and had cervical lymphadenopathy, bi-
lateral basal crepitations with a splenomegaly of 6cm 
and a hepatomegaly of 4cm. His CBC revealed a severe 
pancytopaenia with: Hb% - 3.4 g/dL, WBC – 3.1 x 109/
L, ANC -0.4 x 109/L, platelets 5.0 x 109/L. His blood 
picture and the bone marrow aspirate showed hairy 
cells positive for TRAP. The immunohistochemistry
was positive on the trephine for CD20, CD79a and 
DBA44 confirming the diagnosis of hairy cell leukae-
mia. The flow cytometry (FCM) results on the bone
marrow aspirate was positive for CD19, CD20, CD22, 
CD25, CD11c, FMC7 and kappa light chain.

He was admitted to the Intensive Care Unit with 
acute renal failure and septic shock and the blood cul-
ture showed a heavy growth of yeast. He succumbed 
to septicaemia and died a few weeks after admission 
despite intensive supportive care, broad spectrum an-
tibiotics and antifungal therapy.

C A S E  3 

An Omani male, aged 47 years, a known diabetic on 
oral hypoglycaemics, was referred from a peripheral 
hospital for investigation of pancytopaenia, hepat-

Figure 1: Normal lymphocyte in peripheral blood 
(Magnification x 400)

Figure 2: Hairy cell from peripheral blood from 
patient 1 (Magnification x 4000)



H A I R Y  C E L L  L E U K A E M I A  I N  O M A N

335

osplenomegaly and fever. He had diarrhoea positive 
for salmonella which was treated before he arrived at 
the Royal Hospital. He recounted a two month history 
of backache and fever. He had hepatosplenomegaly 
with no lymphadenopathy. A computed tomography 
(CT) scan showed no evidence of mediastinal lym-
phadenopathy. His CBC revealed an Hb% - 8.9 g/dL, 
WBC – 2.6 x109/L, ANC 0.4x109/L, platelets – 94.0 x 
109/L. The blood picture, bone marrow aspirate and
the trephine biopsy showed hairy cells. The TRAP was
unsatisfactory. The marrow aspirate was inadequate
for FCM. The trephine biopsy was positive for CD79a,
CD20 and DBA44.

He was treated with cladribine 0.14 mg/kg infusion 
over two hours for five days. He had two episodes of
febrile neutropenia which were treated successfully 
with intravenous antibiotics. Six months later, his 
blood count improved to Hb 10.2 G/dL, WBC 3.1x109/
L, ANC 1.9 x109/L and platelets – 141.0 x 109/L.

C A S E  4 

An Iraqi woman, aged 36 years, was referred for pan-
cytopaenia detected on a routine CBC following a 
lower segment caesarian section. A CT scan showed a 
para-aortic lymphadenopathy in her chest and moder-
ate hepatosplenomegaly. Her haematological parame-
ters confirm the presence of bilineage cytopenia: Hb%
-12.0 G/dL, WBC - 1.7 x10 9/L with ANC 0.2x109/L, 
platelets – 102.0x 10 9/L. The bone marrow aspirate

and trephine biopsy showed hairy cells. The trephine
biopsy was positive for CD20, CD79a and DBA44.

The FCM on the bone marrow aspirate was posi-
tive for CD19, CD20, CD22, CD25, CD103, FMC7 and 
kappa light chain. 

She was treated with intravenous cladribine 0.1mg/
kg continuous infusion for seven days. She continues 
to be followed up in the region where she lives and her 
CBC is normal.

D I S C U S S I O N

Middle aged people are more affected by HCL, with a
male-female ratio of 5:1.1 Three of our patients were
male and one was a female.  The characteristic pres-
entation is with pancytopaenia in more than 50% of 
patients, 3 moderate to massive splenomegaly in 85%, 
with or without hepatomegaly in 40% and bone mar-
row infiltration. Opportunistic infections are com-
mon. Rare presentations include vasculitis,4 splenic 
rupture,5 bony involvement,6 neuropathy,7 and au-
toimmune haemolytic anaemia.8 Guillian-Barré syn-
drome has been reported in association with HCL or 
following cladribine treatment.9, 10

The peripheral blood shows the lymphocytes with
shaggy hair like cytoplasmic projections in 90% of 
patients.3 Although it leads to a distinct morphologi-
cal diagnosis, sometimes a severe pancytopaenia, a dry 
bone marrow aspirate due to reticulin fibrosis could
deprive us of this diagnostic information because of 

Figure 3: Tartrate resistent acid phosphatase 
reaction of hairy cell (Patient 2) (Magnification 
x 400)

Figure 4: Trephine biopsy of patient 3 - ‘fried egg’ 
appearance with retraction of cytoplasm around 
the nucleus (Magnification x 400)



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the paucity of cells. Then the diagnosis is often based
on the trephine biopsy which shows a patchy, diffuse
infiltrate  of the hairy cells, described as having a fried
egg or honey comb appearance.3 This occurs because
the lymphocyte nuclei are spaced far apart due to the 
retraction of the cytoplasmic processes. The charac-
teristic infiltrate of the spleen is in the red pulp and
this is the only small B cell non Hodgkin’s lymphoma 
which infiltrates the red pulp of the spleen.3 If the bone 
marrow is not infiltrated, the splenic pathology can be
used to diagnose the condition. 

Infiltration of the kidneys, colon, adrenal glands,
myocardium, meninges, pancreas and connective tis-
sue have been reported.3

Cytochemistry and immunohistochemistry play an 
important role in the diagnosis of HCL. Cytochemis-
try on the hairy lymphocytes in blood or bone marrow 
aspirate with acid phosphatase is resistant to tartrate 
(TRAP). This is also done as immunohistochemistry
on the trephine biopsy. There are no specific chromo-
somal abnormalities or molecular genetic alterations 
that are diagnostic of this disease.1 Thus, morphology,
cytochemistry and immunohistochemistry on the tre-
phine biopsy/flow cytometry are useful tools in diag-
nosis of this uncommon lymphoma in its leukaemic 
phase. The hairy cells strongly express CD 103, CD25,
FMC7, CD11c, and the B cell markers CD20, CD 79a 
and monoclonal kappa or lambda light chains.1 

Supportive care with packed red cells and platelets 
were the mainstay of replacement therapy for the cy-
topaenias in our patients. 

The current treatment of HCL is with the purine
analogues, 2 chlorodeoxyadenosine (2CdA/cladribine) 
and pentostatin. Treatment is indicated for patients 
with significant cytopaenia, syptomatic splenom-
egaly, recurrent serious infections and constitutional 
symptoms. Cladribine is used as a single infusion or 
a course of subcutaneous injections.11 The two widely
used infusion regimens are either 0.1 mg/kg continu-
ous intravenous infusion over 24 hours for seven days 
or 0.14 mg /kg intravenous infusion over two hours 
for five days, with no statistically significant difference
in the rate of response or complications between the 
two regimens.12, 13 A high incidence of febrile neutro-
paenia is recorded with this treatment.14-17 G–CSF is 
used to overcome this side effect. It is rare that more 
than one course of treatment is required. In a recently 
published randomised study in 132 patients with un-
treated HCL, one group of patients were treated with 

the standard regimen of cladribine 0.14mg/kg daily 
for 5 days, while the other group was treated with a 
weekly dose of cladribine for six weeks. Both regimens 
where found to be equally effective; the weekly regi-
men was not, in fact, safer nor did it reduce toxicity 
or the risk of infections.18 Treatment is discontinued 
once complete remission (CR) or partial remission 
(PR) is achieved with normalisation of peripheral 
blood counts.19 Cladribine could induce a durable and 
long lasting remission in the majority of patients with 
only a single cycle of therapy and the relapsed patients 
could be treated successfully with a repeated cycle of 
cladribine.20-22 There is a good correlation between
minimal residual disease as demonstrated by DBA44 
immunostaining and risk of relapse.22

Single IV pentostatin is administered intermittent-
ly for a longer treatment duration, but may result in a 
lower incidence of febrile neutropenia. 23, 24 It is usu-
ally administered in cycles of 4 mg/m2 twice weekly, 
repeated every 8 weeks 25 for three cycles. It was found 
to be highly effective in treating HCL with prolonged
remission duration and without an increase in subse-
quent risk of malignancy.25, 26

Most patients remain disease free for ten years 
following treatment with purine analogues. CR is 
achieved in 80- 85% of patients. No patient has been 
followed up long enough to assess cure.27, 28 The role
of consolidation and maintenance therapy in pre-
venting relapse or progression of the disease has not 
been evaluated. Interferon alfa is also used for those 
patients with intercurrent infections and severe 
cytopenias.29 CR is seen in 20-30% of patients.30 For 
patients with severe thrombocytopaenia and mas-
sive spleens, splenectomy is considered.31 Monoclonal 
antibodies against CD20 (rituximab) and CD22 have 
now shown activity against HCL.30 These antibodies
seem to achieve good responses in the group relapsing 
on cladribine; however, its main role maybe useful in 
combination with purine analogues.30

C O N C L U S I O N

HCL manifests in the middle years of life, with a 
male predominance, characterised by pancytopaenia 
caused by moderate to massive splenomegaly. It is 
an easy diagnosis to make on the morphology of well 
made blood and bone marrow smears. Although there 
are no specific markers for HCL, cytochemistry and
flow cytometry readily confirm the diagnosis. This is 
the first report of HCL in Oman. The diagnosis and



H A I R Y  C E L L  L E U K A E M I A  I N  O M A N

337

management was based on current guidelines. The
outcome of clinical remission was achieved in 3 pa-
tients and one patient succumbed to an opportunistic 
infection.

R E F E R E N C E S

1. Feller AC, Diebold J, Paulli M, Le Tourneau  A. Histopa-
thology of Nodal and Extranodal Non Hodgkin Lym-
phoma. 3rd ed. New York: Springer Publishing Com-
pany, 1992. p. 251-254.

2. Shrek R, Donnelly WJ. Hairy cells in blood in lymphore-
ticular neoplastic disease and flagellated cells of normal
lymph nodes.  Blood 1966; 27:199 –211.

3. Bitter MA, Knowles DM. Hairy Cell Leukaemia and Re-
lated Disorders. In: Neoplastic Haematopathology.  2nd 
ed. Philadelphia: Lippincott, Williams and Wilkins. pp. 
1531-1547.

4. Remkova A, Halcin A, Stenova E, Babal P, Kasoerova V, 
Vranovsky A. Acute vasculitis as a first manifestation of
hairy cell leukemia. Eur J Intern Med 2007; 18:238-240.

5. Dalawari P, Vandover JC, Rosenbaum RA. Unusual 
presentation of spontaneous splenic rupture. Del Med 
J 2007; 79:205-208.

6. Franco P, Filippi AR, Fornari A, Marinone C, Ricardi U.   
Case of bone involvement in hairy cell leukemia suc-
cessfully treated with radiation therapy. Tumori 2006; 
92:366-369.

7. Rossi D, Franceschetti S, Cerri M, Conconi A, Lunghi 
M, Capello D, et al. Hairy cell leukaemia complicated by 
anti-MAG paraproteinemic demyelinating neuropathy: 
resolution of neurological syndrome after cladribrine 
treatment. Leuk Res 2007; 31:873-876.

8. Mainwaring CJ, Walewska R, Snowden J, Winfield DA,
Ng JP, Chan-Lam D, et al. Fatal cord  anti-i autoimmune 
haemolytic anaemia complicating hairy  cell leukaemia. 
Br J Haematol 2000; 109:641-643.

9. Tayal SC, Rowbotham DS, Bansal SK. Guillain-Barré 
syndrome in a patient with hairy cell leukaemia. J R Soc 
Med 1991; 84:238-239. 

10. Sarmiento MA, Neme D, Fornari MC, Bengio RM. 
Guillain-Barre syndrome following 2-chlorodeoxyad-
enosine treatment for Hairy Cell Leukemia. Leuk Lym-
phoma 2000; 39:657-659.

11. Tallman MS, Peterson LC, Hakimian D, Gillis S, Polli-
ack A. Treatment of hairy-cell leukaemia. Current views 
Semin Haematol 1999; 36:155-163. 

12. Sarmiento MA, Neme D, Fornari MC, Bengio RM. 
Guillain-Barre syndrome following 2-chlorodeoxyad-
enosine treatment for Hairy Cell Leukemia. Leuk Lym-
phoma 2000; 39:657-659.

13. Robak T, Błasińska-Morawiec M, Błoński J, Hellmann 
A, Halaburda K, Konopka L, et al.   2 chlorodeoxyad-

enosine (cladribine) in the treatment of hairy cell leuke-
mia and hairy cell  leukemia variant: 7-year experience 
in Poland. Eur J Haematol 1999; 62:49-56.

14. Hoffman MA, Janson D, Rose E, Tai KR. Treatment of
hairy-cell leukaemia with cladribine: response, toxicity, 
and long term follow-up. J Clin Oncol 1997; 15:1138- 
1142.

15. Cheson BD, Sorenson JM, Vena DA, Montello MJ, Bar-
rett JA, Damasio E, et al. Treatment of hairy cell leukae-
mia with 2-chlorodeoxyadenosine via the group C pro-
tocol mechanism of the National Cancer Institute: a re-
port of 979 patients. J Clin Oncol 1998; 16:3007-3015.

16. Goodman GR, Burian C, Koziol JA, Saven A. Extended 
follow-up of patients with hairy cell leukaemia after 
treatment with cladribine. J Clin Oncol 2003; 21:891-
896.

 17. Jehn U, Bartl R, Dietzfelbinger H, Harferlach T, Hein-
emann V.  An update: 12 year follow-up of patients with 
hairy cell leukaemia following treatment with 2-chloro-
deoxyadenosine. Leukaemia 2004; 18:1476-1481.

18. Robak T, Jamroziak K, Gora-Tybor J, Blonski JZ, 
Kasznicki M, Dwilewicz-Trojaczek J, et al. Cladribine in 
a weekly versus daily schedule for untreated active hairy 
cell  leukemia: final report from the Polish Adult Leuke-
mia Group  (PALG) of a  prospective, randomized, mul-
ticenter trial. Blood 2007; 109:3672-3675.

19. Hairy cell leukaemia treatment. National Cancer Insti-
tute, US National Institutes of Health. From www.can-
cer.gov/cancer topics/pdq/treatment/hairy cell leukae-
mia/treatment. Accessed  September 2007.  

20. Jehn U, Bartl R, Dietzfelbinger H.  An update: 12-year 
follow-up of patients with hairy cell leukemia follow-
ing treatment with 2-chlorodeoxyadenosine. Leukemia 
2004; 18:1476-1481.

21. Jehn U, Bartl R, Dietzfelbinger H, Vehling-Kaiser 
U,Wolf-Hornung B, Hill W, et al. Long-term outcome of 
hairy cell leukemia treated with 2-chlorodeoxyadenos-
ine. Ann Hematol 1999; 78:139-144.

22. Bastie JN, Cazals-Hatem D, Daniel MT, D’Agay MF, Ra-
bian C, Glaisner S, et al. Five years follow-up after 2-
chloro deoxyadenosine treatment in thirty patients with 
hairy cell leukemia: evaluation of minimal residual dis-
ease and CD4+ lymphocytopenia after treatment. Leuk 
Lymphoma 1999; 35:555-565.

23. Ribeiro P, Bouaffia F, Peaud PY, Blanc M, Salles B, Salles
G, et al. Long term outcome of patients with hairy cell 
leukaemia treated with pentostatin. Cancer 1999; 85:65-
71.

24. Grever M, Kopecky K, Foucar MK, Head D, Bennett JM, 
Hutchison RE, et al. Randomized comparison of pento-
statin versus interferon alfa -2a in previously untreated 
patients with hairy cell leukaemia: an intergroup study. 
J Clin Oncol 1999; 13:974-982.

25. Johnston JB, Eisenhauer E, Wainman N. Long-term 



A R U N D AT H I  K U R U K U L A S U R I YA ,  A S I A  A L  R A S H D I  A N D  M U H A N N A  A L - M U S L A H I 

338

outcome following treatment of hairy cell leukemia 
with pentostatin (Nipent): a National Cancer Institute 
of Canada study. Semin Oncol 2000; 27:S32-36. 

26. Maloisel F, Benboubker L, Gardembas M, Coiffier B,
Divine M, Sebban C, et al. Long-term outcome with 
pentostatin treatment in hairy cell leukemia patients. 
A French retrospective study of 238 patients. Leukemia 
2003; 17:45-51.

27. Flinn IW, Kopecky KJ, Foucar MK, Head D, Bennett JM, 
Hutchison RE, et al. Long term follow up of remission 
duration, mortality, and second malignancies in hairy 
cell leukaemia patients treated with pentostatin. Blood 
2000; 96:2981-2986.

28. Chadha P, Rademaker AW, Mendiratta P, Kim B, Evan-
chuk DM, Hakimian D, et al. Treatment of hairy cell 

leukaemia with 2- chlorodeoxyadenosine(2CdA): long 
term follow-up of the Northwestern University. Blood 
2005; 106:241-246. 

29. Capnist G, Federico M, Chisesi T, Resegotti L, Lam-
parelli T, Fabris P, et al. Long term results of interferon 
treatment in hairy cell leukaemia: Italian Cooperative 
Group of  Hairy Cell Leukaemia (ICGHCL). Leuk Lym-
phoma 1994; 14:457-464.

30. Hoffbrand AV, Catovsky DC, Tuddenham EGD. Post-
graduate Haematology. 5th ed. Oxford: Blackwell Pub-
lishing, 2005. p. 639. 

31. Golomb HM, Vardiman JW. Response to splenectomy 
in 65 patients with hairy cell leukaemia: an evaluation 
of spleen weight and bone marrow involvement. Blood 
1983; 61:349-352.