Immunophenotypic studies in cutaneous T-cell lymphomas: clinical implications.

Examination of biopsies from 62 patients with, or suspected of having cutaneous T-cell lymphoma (CTCL) revealed 24 cases in which the neoplastic cells expressed aberrant or suppressor T-cell phenotypes. The clinical records of these patients were reviewed in an attempt to establish whether recognition of these phenotypes has any clinical implications. Twelve patients had mycosis fungoides (MF) with plaques (n = 4) or tumours (n = 8), four had Sézary syndrome, and eight had large-cell lymphomas of pleomorphic (n = 6) or anaplastic subtype (n = 2). Most of the large-cell lymphomas behaved aggressively, as might have been expected from their cytological appearance. Aggressive courses were also seen in Sézary syndrome, and in tumour lesions of MF, whereas the behaviour in cases of plaque lesions was indolent. Again, this might have been anticipated from the clinical staging and routine histological examination. It is suggested that the expression of aberrant or suppressor T-cell phenotypes in CTCL is not of independent prognostic significance, but that the stage and histology are more important. This issue is an important topic for a prospective analysis.

T-cell receptor gamma delta-positive peripheral T-cell lymphomas presenting in the skin: a clinical, histological and immunophenotypic study.

Examination of biopsy samples from 62 patients with--or with suspected--cutaneous T-cell lymphoma (CTCL) revealed 2 cases in which the neoplastic cells were positive for the T-cell receptor (TCR) gamma delta complex. One patient had mycosis fungoides and 1 patient had a pleomorphic lymphoma of medium and large-cell type. Both cases showed aggressive courses with dissemination to internal organs and short survival times. The phenotypic examination showed that the neoplastic cells were positive with TCR delta 1, CD3, CD25, CD29, CD45R0 and CD54. No staining was seen with antibodies against framework determinants or variable regions on the TCR alpha beta heterodimer. Negative reactions were also seen with CD4, CD8, CD5, CD7, CD16, CD30 and CD57. It is concluded that rare CTCL express TCR gamma delta chains. These malignancies may originate from the TCR gamma delta-positive T cells seen in normal skin, and it is possible that their recognition may be important for clinical reasons.

Use of antibodies against the variable regions of the T-cell receptor alpha/beta heterodimer for the study of cutaneous T-cell lymphomas.

Recent studies have suggested that antibodies against the variable (V) regions of the T-cell antigen receptor (TCR) may be used as markers for clonality and malignancy in T-cell infiltrates. We have investigated this by examining biopsy samples from 45 patients with cutaneous T-cell lymphomas (CTCL) for reactivity with seven antibodies against different V-gene families on the TCR alpha/beta heterodimer, i.e. ICI (V beta 5a), W112 (V beta 5b), OT145 (V beta 6a), 16G8 (V beta 8a), S511 (V beta 12a), F1 (V alpha 2a) and LC4 (alpha beta Va). Serial biopsies were available in 13 patients and a total of 62 samples were studied. The neoplastic cells in five cases were positive for either V beta 5 (one case), V beta 6 (one case), V beta 8 (two cases) or V beta 12 (one case). In the remaining 40 cases, no staining was seen of the neoplastic cells. These findings indicate that while antibodies against the TCR V-regions may be used as clonotypic markers for certain T-cell neoplasms, there is as yet not a sufficient number of anti-TCR V-region antibodies available for the routine diagnosis of these conditions.