Open AccessAdvanced human T‐cell leukemia virus type 1 carriers and early‐stage indolent adult T‐cell leukemia‐lymphoma are indistinguishable based on CADM 1 positivity in flow cytometry
Author(s) -
Kobayashi Seiichiro,
Watanabe Eri,
Ishigaki Tomohiro,
Ohno Nobuhiro,
Yuji Koichiro,
Nakano Kazumi,
Yamochi Tadanori,
Watanabe Nobukazu,
Tojo Arinobu,
Watanabe Toshiki,
Uchimaru Kaoru
Publication year - 2015
Publication title -
cancer science
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 2.035
H-Index - 141
eISSN - 1349-7006
pISSN - 1347-9032
DOI - 10.1111/cas.12639
Subject(s) - flow cytometry , leukemia , lymphoma , adult t cell leukemia/lymphoma , biology , asymptomatic carrier , cd8 , immunology , asymptomatic , virology , microbiology and biotechnology , medicine , t cell leukemia , antigen
We previously reported that the cell adhesion molecule 1 ( CADM 1) versus CD 7 plot in flow cytometry reflects disease progression in human T‐cell leukemia virus type 1 ( HTLV ‐1) infection. In CD 4 + cells from peripheral blood, CADM 1 − CD 7 + (P), CADM 1 + CD 7 dim (D) and CADM 1 + CD 7 − (N) subpopulations are observed. The D and N subpopulations increase as asymptomatic HTLV ‐1 carriers ( AC ) progress to indolent adult T‐cell leukemia‐lymphoma ( ATL ) and the N subpopulation then expands in aggressive ATL . In the present study we examined whether the analysis can estimate the risk of developing ATL in advanced AC . Peripheral blood samples from AC ( N = 41) and indolent ATL patients ( N = 19) were analyzed by flow cytometry using the CADM 1 versus CD 7 plot for CD 4 + cells and inverse long PCR (clonality analysis) of FACS ‐sorted subpopulations. Almost all AC with a high HTLV ‐1 proviral load (>4 copies/100 cells) had a CADM 1 + (D + N) frequency of >10%. AC with 25% < CADM 1 + ≤ 50% contained expanded clones similar to smoldering‐type ATL . In many patients in the 25% < CADM 1 + ≤ 50% group, the proportion of abnormal lymphocytes was distributed around the 5% line, which divides AC and smoldering‐type ATL in Shimoyama's classification. In conclusion, the CADM 1 versus CD 7 plot is useful for selection of putative high‐risk AC . The characteristics of some AC and smoldering ATL are said to be similar; however, long‐term follow up is required and the clinical outcome (e.g. rate of transformation) of these cases should be used to determine whether to include them in the same clinical category.