Clinicopathological analysis of the age-related differences in patients with Epstein-Barr virus (EBV)-associated extranasal natural killer (NK)/T-cell lymphoma with reference to the relationship with aggressive NK cell leukaemia and chronic active EBV infection-associated lymphoproliferative disorders.
OBJECTIVE
Extranodal natural killer (NK)/T-cell lymphoma (NKTL), comprising nasal NKTL and extranasal NKTL (ENKTL), is associated with Epstein-Barr virus (EBV). A bimodal age distribution was noted in NKTL patients. We examined the clinicopathological differences between two age groups of ENKTL patients (n = 23) and compared the findings with those of aggressive NK cell leukaemia (ANKL; n = 10) and monoclonal chronic active EBV infection-associated T/NK-cell lymphoproliferative disorders [chronic active EBV infection/TNK-lymphoproliferative disorders (CAEBV/TNK-LPD)] of NK-cell type (n = 45).


RESULTS
Distinct differences existed between elderly (> 50 years; n = 13) and younger (≤ 50 years; n = 10) ENKTL patients; the latter showed a higher disease stage (P = 0.0286), worse performance status (P = 0.0244), more frequent B symptoms (P = 0.0286) and more frequent liver, spleen and bone marrow involvement (P = 0.0222, 0.0005 and 0.0259, respectively). Few clinicopathological differences existed between younger ENKTL and ANKL patients. Patients with monoclonal CAEBV/TNK-LPD of NK-cell type (n = 45) showed features similar to those in younger ENKTL/ANKL patients, except a more juvenile onset of CAEBV-related symptoms and better prognosis. However, the onset age of overt leukaemia/lymphoma in CAEBV/TNK-LPD patients and overall survival thereafter were similar to those in younger ENKTL/ANKL patients.


CONCLUSIONS
ENKTL (≤ 50 years) is distinct from that in elderly patients and may encompass ANKL and overlap in the clinicopathological profile with NK-cell type CAEBV/TNK-LPD.
Department of Pathology, Aichi Medical University Hospital, Nagakute, Japan.
Emiko
E
Takahashi
Koichi
K
Ohshima
Hiroshi
H
Kimura
Kazuo
K
Hara
Ritsuro
R
Suzuki
Keisei
K
Kawa
Tadaaki
T
Eimoto
Shigeo
S
Nakamura
D000293:Adolescent; D000328:Adult; D017677:Age Distribution; D000367:Age Factors; D000368:Aged; D000369:Aged, 80 and over; D002648:Child; D002675:Child, Preschool; D002908:Chronic Disease; D020031:Epstein-Barr Virus Infections / Q000150:complications* / Q000401:mortality / Q000473:pathology; D005260:Female; D006801:Humans; D016130:Immunophenotyping; D053208:Kaplan-Meier Estimate; D054066:Leukemia, Large Granular Lymphocytic / Q000401:mortality / Q000473:pathology* / Q000821:virology; D054391:Lymphoma, Extranodal NK-T-Cell / Q000401:mortality / Q000473:pathology* / Q000821:virology; D008232:Lymphoproliferative Disorders / Q000401:mortality / Q000473:pathology* / Q000821:virology; D008297:Male; D008875:Middle Aged; D009367:Neoplasm Staging; D055815:Young Adult