Aggressive NK-cell leukemia
Editor-In-Chief: C. Michael Gibson, M.S., M.D. [2] Associate Editor(s)-in-Chief: Maria Fernanda Villarreal, M.D. [3] Synonyms and keywords: ANKL
Overview
Aggressive NK-cell leukemia is a disease with an aggressive, systemic proliferation of natural killer cells (NK cells) and a rapidly declining clinical course. There is no classification system for aggressive NK-cell leukemia. The pathogenesis of aggressive NK-cell leukemia is characterized by the proliferation of natural killer cells. Aggressive NK-cell leukemia is very uncommon, and is most commonly seen among middle aged adults. The most common risk factors in the development of aggressive NK-cell leukemia is the Epstein-Barr virus (EBV) infection. The majority of patients with aggressive NK-cell leukemia are symptomatic at diagnosis. Early clinical features include fatigue, night sweats, and fever. Physical examination among patients with aggressive NK-cell leukemia may be remarkable for hepatosplenomegaly. Aggressive NK-cell leukemia may also be diagnosed using bone marrow biopsy, findings of which can include extensive marrow replacement by leukemic cells and reactive histiocytes displaying hemophagocytosis. The mainstay of therapy for aggressive NK-cell leukemia is anthracycline-containing chemotherapy.
Classification
There is no classification system for aggressive NK-cell leukemia.[1]
Pathophysiology
- The pathogenesis of aggressive NK-cell leukemia is characterized by the aggressive, systemic proliferation of natural killer cells.
- The mutation in oncogene p53 has been associated with the development of aggressive NK-cell leukemia.
- On gross pathology, characteristic findings of aggressive NK-cell leukemia include:
- No remarkable findings
- On microscopic histopathological analysis, characteristic findings of aggressive NK-cell leukemia include:[1]
- The table below demonstrates the immunophenotype for patients with aggressive NK-cell leukemia.[1]
Causes
There are no established causes for aggressive NK-cell leukemia.
Differentiating Aggressive NK-cell Leukemia from Other Diseases
Aggressive NK-cell leukemia must be differentiated from other diseases that cause fever, fatigue, and lymphadenopathy such as:
Epidemiology and Demographics
- Aggressive NK-cell leukemia is a rare disorder.[2]
- Aggressive NK-cell leukemia is more commonly observed among young adults with median age of 42 years old.
- Aggressive NK-cell leukemia affects men more frequently than women.
- Aggressive NK-cell leukemia usually affects individuals of the Asian race.
Risk Factors
Common risk factors in the development of aggressive NK-cell leukemia include Epstein-Barr virus (EBV) infection[2]
Natural History, Complications, and Prognosis
- The majority of patients with aggressive NK-cell leukemia are symptomatic at the time of diagnosis.
- Early clinical features include fatigue, night sweats, and fever.
- If left untreated, patients with aggressive NK-cell leukemia may progress to develop recurrent infections.
- Common complications of aggressive NK-cell leukemia, include:
- Prognosis is generally poor, and the median survival rate of patients with aggressive NK-cell leukemia is few months.
Diagnosis
Symptoms
- Symptoms of aggressive NK-cell leukemia may include the following:[1]
- Fever
- Swelling in the lymph nodes in the neck
- Night sweats
- Persistent fatigue
- Loss of appetite
- Weight loss
- Nausea
- Vomiting
- Yellow discoloration of the sclera
- Enlarged liver or spleen
Physical Examination
- Patients with aggressive NK-cell leukemia usually appear icteric and malnourished.[3]
- Physical examination may be remarkable for:
- Fever
- Hepatoesplenomegaly
- Lymphadenopathy
Laboratory Findings
- Laboratory findings consistent with the diagnosis of aggressive NK-cell leukemia include:[4]
Peripheral Blood Smear
- Large granular lymphocyte (LGL)
- Fine or coarse azurophilic granules and nucleoli of varying prominence
- Nuclei may be irregular and hyperchromatic
Imaging Findings
There are no imaging findings associated with aggressive NK-cell leukemia.
Other Diagnostic Studies
- Aggressive NK-cell leukemia may also be diagnosed using bone marrow biopsy.
- Findings on bone marrow biopsy, include:[4]
- Extensive marrow replacement by leukemic cells
- Reactive histiocytes displaying hemophagocytosis
Treatment
Medical Therapy
- The mainstay of therapy for aggressive NK-cell leukemia is anthracycline-containing chemotherapy.[4]
- L-asparaginase containing chemotherapy regimen followed by allogeneic stem cell transplantation shows to slightly prolong life, but relapse is almost assured.[5]
- Other novel treatments may include pralatrexate.[4]
Surgery
- Surgery is not recommended among patients with aggressive NK-cell leukemia.
Prevention
- There are no primary preventive measures available for aggressive NK-cell leukemia.
References
- ↑ 1.0 1.1 1.2 1.3 [1] Chan JK. "Natural killer cell neoplasms." Anat Pathol. 1998;3:77-145. PMID 10389582
- ↑ 2.0 2.1 Suzuki, R; Suzumiya, J; Nakamura, S; Aoki, S; Notoya, A; Ozaki, S; Gondo, H; Hino, N; Mori, H; Sugimori, H; Kawa, K; Oshimi, K (2004). "Aggressive natural killer-cell leukemia revisited: large granular lymphocyte leukemia of cytotoxic NK cells". Leukemia. 18 (4): 763–770. doi:10.1038/sj.leu.2403262. ISSN 0887-6924.
- ↑ Li, Chunrui; Tian, Ye; Wang, Jue; Zhu, Li; Huang, Liang; Wang, Na; Xu, Danmei; Cao, Yang; Li, Jianyong; Zhou, Jianfeng (2014). "Abnormal immunophenotype provides a key diagnostic marker: a report of 29 cases of de novo aggressive natural killer cell leukemia". Translational Research. 163 (6): 565–577. doi:10.1016/j.trsl.2014.01.010. ISSN 1931-5244.
- ↑ 4.0 4.1 4.2 4.3 Aggressive NK-cell leukemia. https://en.wikipedia.org/wiki/Aggressive_NK-cell_leukemia Accessed on May 5, 2016
- ↑ Ishida, F; Ko, YH (2012 June). "Aggressive natural killer cell leukemia: therapeutic potential of L-asparaginase and allogeneic hematopoietic stem cell transplantation". Cancer Sci. 103(6): 1079–83. PMID 22360679. Check date values in:
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