Expression of JL1 is an effective adjunctive marker of leukemia cutis.
BACKGROUND
Specific differentiation of leukemia cutis (LC) from nonleukemic dermatoses is crucial to ensure proper treatment for the disease. Because of the exceptionally variable histologic features of LC and the frequent nonleukemic dermatoses in leukemia patients, identification of leukemic cells that infiltrate skin lesions is important. Here, we introduce JL1, a novel leukemia-associated surface antigen, which is not expressed in mature human tissue but in cortical thymocytes and small subpopulations of bone marrow hematopoietic precursors.


OBJECTIVE
To assess the expression pattern of JL1 in LC and compare it with other commonly used markers. Also, to evaluate the expression of JL1 in other cutaneous lesions that need differential diagnoses.


METHODS
Immunohistochemical staining with anti-JL1 and other commonly used markers for LC was performed on paraffin-embedded skin biopsies from 32 cases of LC with acute lymphoblastic leukemia/lymphoma and acute myelogenous leukemia. Immunohistochemical staining score was evaluated in each case according to the proportion of positive tumor cells found. JL1 staining was also done on 96 reactive or neoplastic cutaneous lesions.


RESULTS
JL1 was detected in 7 of 11 acute lymphoblastic leukemia/lymphoma LC (63.6%) and 7 of 21 acute myelogenous leukemia LC (33.3%), with invariably high-staining scores. None of the other cutaneous lesions or normal tissues expressed JL1. The expression pattern of JL1 was not altered in 2 patients with follow-up biopsies.


CONCLUSIONS
Our finding that JL1 is expressed exclusively and stably by leukemic cells suggests that it can be used as a useful adjunctive marker for initial diagnosis and follow-up biopsy of LC, particularly in cases of scarce infiltrates.
Park
Young Soo
YS
Department of Pathology, University of Ulsan College of Medicine, Asan Medical Center, Seoul, Korea.
Park
So Hyung
SH
Park
Seo-Jeong
SJ
Kim
Youngji
Y
Jang
Kee-Taek
KT
Ko
Young Hyeh
YH
Lee
Mi-Woo
MW
Huh
Joo Ryung
JR
Park
Chan-Sik
CS
D000293:Adolescent; D000328:Adult; D000368:Aged; D000945:Antigens, Differentiation, T-Lymphocyte / Q000378:metabolism*; D014408:Biomarkers, Tumor / Q000276:immunology*; D001706:Biopsy; D002648:Child; D002675:Child, Preschool; D003937:Diagnosis, Differential; D005260:Female; D006086:Graft vs Host Disease / Q000175:diagnosis / Q000276:immunology / Q000473:pathology; D006801:Humans; D007223:Infant; D007231:Infant, Newborn; D015470:Leukemia, Myeloid, Acute / Q000175:diagnosis / Q000276:immunology* / Q000473:pathology; D017254:Leukemic Infiltration / Q000276:immunology / Q000473:pathology; D008297:Male; D008875:Middle Aged; D054198:Precursor Cell Lymphoblastic Leukemia-Lymphoma / Q000175:diagnosis / Q000276:immunology* / Q000473:pathology; D012189:Retrospective Studies; D012680:Sensitivity and Specificity; D012867:Skin / Q000276:immunology / Q000473:pathology; D012871:Skin Diseases / Q000175:diagnosis / Q000276:immunology / Q000473:pathology; D012878:Skin Neoplasms / Q000175:diagnosis / Q000276:immunology* / Q000473:pathology; D016463:Sweet Syndrome / Q000175:diagnosis / Q000276:immunology / Q000473:pathology; D055815:Young Adult
D000945:Antigens, Differentiation, T-Lymphocyte; D014408:Biomarkers, Tumor; C114952:JL1 antigen