Cancer Translational Medicine

CASE REPORT
Year
: 2015  |  Volume : 1  |  Issue : 5  |  Page : 181--182

Acute Lymphoblastic Leukemia with Normal Platelet Count


Khushboo Dewan, Kiran Agarwal 
 Department of Pathology, Lady Hardinge Medical College and Associated Hospitals, New Delhi, India

Correspondence Address:
Khushboo Dewan
Department of Pathology, Lady Hardinge Medical College and Associated Hospitals, 26, Amit Apartments, Sector-13, Rohini, New Delhi 110085
India

Abstract

B-acute lymphoblastic leukemia (B-ALL) often presents with pancytopenia/bicytopenia, with thrombocytopenia being the most important parameter. The case of a 12-year-old child with bicytopenia on peripheral smear was presented. On bone marrow examination, 85% morphologically lymphoid blasts, negative for myeloperoxidase, and periodic-acid Schiff on cytochemistry were found. The blasts suppressed the erythroid population but not the megakaryocytic population. On flow cytometry, a diagnosis of common-ALL-antigen positive B-precursor ALL was concluded. To conclude, ALL cannot be excluded in patients who present with a normal platelet count. A bone marrow aspirate is crucial in patients with bi/pancytopenia.



How to cite this article:
Dewan K, Agarwal K. Acute Lymphoblastic Leukemia with Normal Platelet Count.Cancer Transl Med 2015;1:181-182


How to cite this URL:
Dewan K, Agarwal K. Acute Lymphoblastic Leukemia with Normal Platelet Count. Cancer Transl Med [serial online] 2015 [cited 2019 Jun 16 ];1:181-182
Available from: http://www.cancertm.com/text.asp?2015/1/5/181/168576


Full Text

 Introduction



B-acute lymphoblastic leukemia (B-ALL) is a neoplasm of precursor cells committed to the B-cell lineage involving bone marrow and blood.[1] The lymphoblasts are small to medium-sized cells with scant cytoplasm, moderately condensed to dispersed chromatin, and inconspicuous nucleoli.[1] B-ALL most commonly presents with evidence of bone marrow failure in the form of fatigue, lethargy, persistent fever, bruising or bleeding, and bone and joint pain.[2] This is because proliferation and accumulation of blast cells in the marrow result in suppression of hematopoiesis and, thereafter, thrombocytopenia and/or anemia and/or neutropenia.[3] The median age of the patients with ALL is 14 years with 60% of patients diagnosed younger than 20 years of age.[4] The leukocyte count may be reduced, normal, or markedly increased.[1] We present an unusual case of B-ALL, who had a normal platelet count on peripheral smear despite anemia and leukopenia.

 Case Report



A 12-year-old female presented with a history of high grade, continuous fever, malaise, weakness, and breathlessness on exertion for 2 months duration. The patient did not have any significant past medical history or family history. On examination, she was well built but pale and no rashes, lymphadenopathy, or organomegaly was present. A routine hemogram revealed bicytopenia with hemoglobin being 3.7 g/dL, red blood cell count of 1.3 million/μL, and a total leukocyte count of 1,000 cells/μL. The red blood cells were predominantly normocytic, normochromic, and a differential leukocyte count showed 75% lymphocytes but no blasts. Platelets were adequate with a count of 225 × 10[3]/μL with few large platelets. The platelet indices, namely mean platelet volume, plateletcrit, and platelet-large cell ratio were all normal. Bone marrow aspirate smears were cellular with the presence of 85% morphologically lymphoid blasts [Figure 1]. There was suppression of erythroid and myeloid series by the blast population. However, megakaryocytes were increased in number with the presence of few micro-megakaryocytes and many dysplastic forms. Therefore, a possible diagnosis of acute myeloid leukemia-M7 was also considered. The blasts were myeloperoxidase and periodic-acid Schiff stains negative. On flow cytometry, these blasts were confirmed to be negative for CD41 and were instead CD19, CD10, CD79a dim-to-moderate positive with CD10 and CD19 co-expression in 95.8% blasts [Figure 2]. In addition, blasts were CD34 and terminal deoxynucleotidyl transferase dim-to-moderate positive and negative for myeloid markers. A diagnosis of common-ALL-antigen positive precursor B-cell ALL was reported. The patient is currently receiving induction phase of chemotherapy and is responding well.{Figure 1}{Figure 2}

 Discussion



Patients with ALL often present at the time of diagnosis with pancytopenia or bicytopenia (most commonly anemia and thrombocytopenia with leukocytosis) but may sometimes have normal peripheral blood cell counts. Of the three peripheral blood series, platelet series is the earliest and the most consistently decreased series in ALL cases at the time of diagnosis and even at relapse. It is understandable that patients with ALL have anemia and thrombocytopenia with leukocytosis/leukopenia because the blasts cause replacement and suppression of the normal hematopoietic elements. However, Straus et al.[5] reported an elevated immature platelet fraction in ALL cases, suggesting that although bone marrow progenitors are absent, thrombopoiesis is present. In this case, the patient had 85% blasts in bone marrow causing suppression of the erythroid series but leaving the megakaryocytic lineage unaffected. This was intriguing, and we kept the differential diagnosis of acute myeloid leukemia-M7 for this case on preliminary peripheral smear and bone marrow aspirate examination. Despite extensive literature search, not many such cases seem to have been reported. A single study by Hara et al.[6] published in 1990 has reported 36 of 202 children (18%) with ALL to have a platelet count > 150 × 109/μL at diagnosis. Hara et al.[6] found this phenomenon to be related to the male gender, less marked leukocytosis, less severe anemia, less frequent bleeding manifestations and a lower percentage of bone marrow blasts. The present case, however, is a female with leukopenia, severe anemia, no bleeding manifestations and 85% bone marrow blasts. The bone marrow blasts, therefore, chose to suppress the erythroid series causing severe anemia, leaving the megakaryocytic lineage and platelet count unaffected. Hara et al.[6] has also found a better prognosis in the form of a higher chance of complete remission in these patients. The patient under study responded well to induction therapy and is under close follow-up.

In conclusion, the case under discussion highlights that ALL may even present with anemia, and/or leukopenia but a normal platelet count. ALL cannot be excluded in such cases, and a bone marrow examination along with flow cytometry is crucial for work-up.

 Acknowledgments



We are grateful to our Head of Department, Dr. Manjula Jain, for her constant support and encouragement.

Financial support and sponsorship

Nil.

Conflicts of interest

There are no conflicts of interest.

References

1Swerdlow SH, Campo E, Harris NL, Jaffe ES, Pileri SA, Stein H, Thiele J, Vardiman JW. WHO Classification of Tumors of Hematopoietic and Lymphoid Tissues. 4th ed. Lyon: IARC; 2008.
2Raetz EA, Loh ML, O'Brien MM, Whitlock JA. Acute lymphoblastic leukemia in children. In: Greer JP, Arber DA, Glader B, List AF, Means RT, Paraskevas F, Rodgers GF, editors. Wintrobe's Clinical Hematology. 13th ed. Philadelphia: Lippincott, Williams and Wilkins; 2014. p. 1616–36.
3Lichtman MA, Beutler E, Kipps TJ, Seligsohn U, Kaushansky K, Prchal JT, editors. William's Hematology. 7th ed. New York: McGraw Hill; 2006.
4National Comprehensive Cancer Network. NCCN Clinical Practice Guidelines in Oncology: Acute Lymphoblastic Leukemia. Ver. 2.2015. Fort Washington: National Comprehensive Cancer Network; 2015.
5Straus G, Vollert C, von Stackelberg A, Weimann A, Gaedicke G, Schulze H. Immature platelet count: a simple parameter for distinguishing thrombocytopenia in pediatric acute lymphocytic leukemia from immune thrombocytopenia. Pediatr Blood Cancer 2011; 57 (4): 641–7.
6Hara T, Mizuno Y, Ikuno Y, Okamura J, Nagata M, Ishii E, Yamada S, Tasaka H, Ueda K. Acute leukemia with normal platelet count at diagnosis. Acta Paediatr Jpn 1990; 32 (5): 515–8.