Heterogeneity of cutaneous T-cell lymphoma. Phenotypic and ultrastructural characterization of four unusual cases

Histopathology and genetics of cutaneous T-cell lymphoma

There is emerging evidence that genomic and chromosomal instability are features of CTCL, including variants such as MF, Sézary syndrome, and primary cutaneous CD30+ LCAL, and that specific chromosomal abnormalities are common. Additional resolution of specific regions of chromosomal loss and gain are required to define putative genes that may be of fundamental pathogenetic importance in CTCL. Inactivation of well-defined cell cycle and TSG are common as for other types of NHL. The prognostic significance of these abnormalities in CTCL has yet to be determined. The dysregulation of specific transcription factors is of interest, but requires further study. It is hoped that greater understanding of these molecular abnormalities will permit the development of CTCL-specific therapies that alleviate suffering and prolong survival.

Cytotoxic/natural killer cell cutaneous lymphomas. Report of EORTC Cutaneous Lymphoma Task Force Workshop

BACKGROUND

Cutaneous lymphomas expressing a cytotoxic or natural killer (NK) cell phenotype represent a group of lymphoproliferative disorders for which there is currently much confusion and little consensus regarding the best nomenclature and classification.

METHODS

This study analyzes 48 cases of primary cutaneous lymphoma expressing cytotoxic proteins and/or the NK cell marker, CD56. These cases were collected for a workshop of the European Organization for Research and Treatment of Cancer Cutaneous Lymphoma Task Force, to better clarify the clinical, morphologic, and phenotypic features of these uncommon tumors.

RESULTS

Several categories with different clinical and pathologic features were delineated: 1) aggressive, CD8+, epidermotropic, cytotoxic T-cell lymphoma; 2) mycosis fungoides, cytotoxic immunophenotype variant; 3) subcutaneous panniculitis-like T-cell lymphoma; 4) NK/T-cell lymphoma, nasal type; 5) CD4+, NK cell lymphoma; 6) blastoid NK cell lymphoma; (7) intravascular NK-like lymphoma; and 8) cytotoxic, peripheral T-cell lymphoma.

CONCLUSIONS

Our data show that primary cutaneous cytotoxic/NK cell lymphomas include distinct groups of diseases, clinically, histologically, and biologically. Because the finding of a cytotoxic phenotype often has prognostic significance, the routine use of cytotoxic markers in the diagnosis and classification of cutaneous lymphomas should be expanded.

Primary cutaneous CD8-positive epidermotropic cytotoxic T cell lymphomas. A distinct clinicopathological entity with an aggressive clinical behavior

Cutaneous T cell lymphomas (CTCL) generally have the phenotype of CD3+, CD4+, CD45RO+ memory T cells. CTCL expressing a CD8+ T cell phenotype are extremely rare and ill-defined. To elucidate whether these CD8+ CTCL represent a distinct disease entity, the clinical, histological, and immunophenotypical features of 17 CD8+ CTCL were reviewed. None of the 17 cases expressed markers characteristic of natural killer cells or gamma/delta T cells. Nine of 17 cases showed the characteristic clinical and histological features as well as clinical behavior of well defined types of CTCL, such as mycosis fungoides (2 cases), pagetoid reticulosis (2 cases), lymphomatoid papulosis (2 cases), and CD30+ large T cell lymphoma (2 cases), all of which usually express a CD4+ T cell phenotype, and 1 case of subcutaneous panniculitis-like T cell lymphoma. The other 8 cases formed a homogeneous group showing a distinctive set of clinicopathological and immunophenotypical features, not consistent with that of other well defined types of CTCL. Clinical characteristics included presentation with generalized patches, plaques, papulonodules, and tumors mimicking disseminated pagetoid reticulosis; metastatic spread to unusual sites, such as the lung, testis, central nervous system, and oral cavity, but not to the lymph nodes; and an aggressive course (median survival, 32 months). Histologically, these lymphomas were characterized by band-like infiltrates consisting of pleomorphic T cells or immunoblasts, showing a diffuse infiltration of an acanthotic epidermis with variable degrees of spongiosis, intraepidermal blistering, and necrosis. The neoplastic cells showed a high Ki-67 proliferation index and expression of CD3, CD8, CD7, CD45RA, betaF1, and TIA-1 markers, whereas CD2 and CD5 were frequently lost. Expression of TIA-1 pointed out that these lymphomas are derived from a cytotoxic T cell subset. The results of this and other studies reviewed herein suggest that these strongly epidermotropic primary cutaneous CD8+ cytotoxic T cell lymphomas represent a distinct type of CTCL with an aggressive clinical behavior.

Primary cutaneous T-cell lymphoma: clinicopathological features and prognostic parameters of 35 cases other than mycosis fungoides and CD30-positive large cell lymphoma

Within the group of primary cutaneous T-cell lymphomas (CTCLs), mycosis fungoides (MF), Sézary's syndrome (SS), and CD30-positive lymphomas have been delineated as clinicopathological entities. Primary CTCLs that do not belong to one of these entities represent a heterogeneous and ill-defined group of neoplasms. This paper describes the clinical and histological features of 35 of such cases. The object of this study was to define prognostic parameters for this group of primary CTCLs. Using a slightly modified version of the updated Kiel classification, a subdivision was made into CTCL, pleomorphic, small cell type (n = 3); pleomorphic, medium-sized cell type (n = 6); pleomorphic, large cell type (n = 18); and immunoblastic lymphomas (n = 8). Altogether, these lymphomas had a poor prognosis with estimated 2- and 4-year survival rates of 53 and 22 percent, respectively. Patients with pleomorphic, small and medium-sized cell lymphomas (n = 9) proved to have a significantly better survival than those with pleomorphic, large cell lymphomas (P = 0.032) and immunoblastic lymphomas (P = 0.008). Primary cutaneous immunoblastic lymphomas had the worst prognosis with an estimated 2-year survival rate of 14 percent. Other parameters including age (P = 0.345), sex (P = 0.662), extent of skin lesions at presentation (P = 0.0854), and mode of initial treatment (P = 0.609) had no significant effect on the survival time. The results of this study suggest that primary CTCLs other than classical MF, SS, and CD30-positive lymphomas have a poor prognosis in most cases, and that the current classification may be a useful means of predicting the clinical behaviour in these lymphomas.

HTLV-1-negative pleomorphic T-cell lymphoma of the skin: the clinicopathological correlations and natural history of 15 patients

The peripheral T-cell lymphomas represent a heterogeneous group and include, besides mycosis fungoides and Sézary syndrome, large-cell anaplastic lymphoma. We report 15 cases from our files that fulfil the histological criteria of pleomorphic T-cell lymphoma with primary skin involvement. Most of the cases were elderly with a male-to-female ratio of 1.5:1. The HTLV-1 serology was negative. The clinical features of these patients differed from those with mycosis fungoides and Sézary syndrome, in that eczematous and precursor lesions such as parapsoriasis en plaque were lacking apart from one exception. All the patients with small-cell pleomorphic T-cell lymphomas were alive, although three of the nine patients with medium-to-large tumour cells have died. Pleomorphic T-cell lymphoma should be regarded as a distinct entity among the lymphoproliferative disorders of the skin.

CD8+ cutaneous anaplastic large-cell lymphoma: report of two cases with immunophenotyping, T-cell-receptor gene rearrangement and electron microscopic studies

Two cases are reported of cutaneous anaplastic large-cell lymphoma with the suppressor/cytotoxic (CD8) phenotype. In both cases there was a solitary skin tumour in which there was a dense infiltrate with large irregularly shaped cells which on immunophenotyping expressed CD8. DNA hybridization analysis showed rearrangements of the T-cell-receptor gene in both cases.

Cutaneous T-cell lymphoma: utility of antibodies to the variable regions of the human T-cell antigen receptor

BACKGROUND

The clonotypic 90 kd Ti heterodimer of the human T-cell antigen receptor is composed of two distinct chains (alpha beta or rarely tau delta) that result from the recombination of variable (V), constant, joining, and, in the case of beta chains, additional diversity regions.

OBJECTIVE

The variable region expression of human cutaneous T-cell lymphoma (CTCL) was studied.

METHODS

Biopsy specimens from 13 patients with CTCL (7 plaque, 3 tumor stage, 3 Sézary syndrome) were examined immunohistochemically by a panel of seven commercially available monoclonal V-region antibodies.

RESULTS

Two patients had significant anti-V-region staining. One patient with Sézary syndrome had two lesions, subjected to biopsy 4 months apart, that reacted with beta V5(a), a specificity previously documented by flow cytometry of leukemic cells. A patient with plaque-stage CTCL, negative for T-cell gene rearrangement by Southern blot, demonstrated reactivity with beta V5(c) largely limited to epidermotropic lymphocytes.

CONCLUSION

Panels of V-region antibodies should be useful reagents for diagnosis and follow-up of CTCL.

Cutaneous angiocentric T-cell lymphoma associated with Epstein-Barr virus

BACKGROUND

Two unusual cases of cutaneous angiocentric T-cell lymphoma were found to be associated with Epstein-Barr virus infection.

OBJECTIVE

The objective was to study the clinical course and the response of the disease to conventional chemotherapy.

METHODS

Histologic specimens from both patients were studied. Clonal proliferation was assessed by Southern blot hybridization.

RESULTS

The disease in both patients was rapidly progressive and responded poorly to aggressive treatment. Biopsy specimens showed infiltration of atypical lymphoid cells with angiocentricity and angiodestruction, which probably resulted in the observed tissue necrosis. Clonal proliferation of Epstein-Barr virus DNA was detected in tissue from primary skin lesions and disseminated nasal lesions.

CONCLUSION

Epstein-Barr virus-associated angiocentric T-cell lymphoma in our patients was characterized by an aggressive course and resistance to conventional chemotherapy. A search for Epstein-Barr virus and the human T-lymphotropic virus should be performed in patients with atypical features of cutaneous T-cell lymphoma.

Lymphoid proliferation and lymphoma associated with human retroviruses (HTLV and HIV)

There are rapidly increasing opportunities for dermatologists to see patients suffering from retrovirus infections. The HTLV-I was the first class of human oncogenic retrovirus that was found in cultured cells of a patient with skin manifestations similar or identical to those of CTCL (MF). It was soon recognized as the agent causing ATLL. The skin manifestations, histopathology, and immunophenotypes of ATLL share many similarities with MF and SS. Both HTLV-I and HIV-I (HTLV-III) cause immunodeficiency with an increased susceptibility to opportunistic infections. Persistent generalized lymphadenopathies are the initial manifestations of most of the HIV infections. The incidence of lymphoid malignancies is expected to become much higher as the life span of AIDS patients is prolonged. They can have both B-cell and T-cell non-Hodgkin lymphomas, although the incidence of the latter (B-cell lymphoma) is still much higher than that of the former. All human retroviruses are transmitted in similar ways.

Immunoblastic T-cell lymphoma presenting as an eyelid tumor

A 59-year-old white man presented with an ulcerating mass of the left upper eyelid of 6 months' duration. A biopsy specimen of the tumor was diagnosed as an immunoblastic T-cell malignant lymphoma. The lesion completely regressed after 4000 cGy of cobalt-60 radiation therapy. In the ensuing 33 months, multiple, widespread skin nodules of the same neoplasm developed including a right upper eyelid tumor. To the authors' knowledge, this is the first reported case of an immunoblastic T-cell lymphoma initially manifesting as an eyelid neoplasm.

Immunohistochemical classification of cutaneous pseudolymphomas: delineation of distinct patterns

Because of the broad spectrum of clinical and histological features, cutaneous pseudolymphomas are difficult to classify. To delineate objective criteria for classification, we investigated the immunoarchitecture of 53 cases of pseudolymphomas; 29 were classified as T cell pseudolymphomas. The immunohistologic characteristics were the absence of B cell compartments, the predominance of T helper-inducer cells and the presence of Langerhans cells/indeterminate cells. Lymphomatoid contact dermatitis showed the bandlike (superficial) T cell pattern. Lymphocytic infiltration of the skin, lymphomatoid papulosis, lymphomatoid drug reactions, and persistent nodules following assaults by arthropods revealed a nodular T cell pattern. Twenty-four cases represented B cell pseudolymphomas containing a nodular arrangement of B lymphocytes. In 6 lesions, there were B cell aggregates without the association of dendritic reticulum cells (non follicular B cell pattern); in 18, the B cell clusters were associated with dendritic reticulum cells and a typical expression of IgM and IgD, thus forming fully developed germinal centers (follicular B cell pattern). The B cell clusters were always surrounded by distinct T zones. B cell patterns were present in lymphadenosis benigna cutis, large cell lymphocytoma and occasionally, in persistent nodules, following assaults by arthropods.

Characterization of the spectrum of postthymic T-cell malignancies in Taiwan. A clinicopathologic study of HTLV-1-positive and HTLV-1-negative cases

Postthymic T-cell malignancy shows marked geographic, clinicopathologic, and prognostic diversity. The frequency and spectrum of T-cell malignancies in Taiwan were investigated. Fifty-two patients (35 male and 17 female) with a median age of 49 years, were consecutively encountered between October 1983 and April 1987; these accounted for 39% of non-Hodgkin's lymphoma cases seen in our institutions. Ten patients (19.3%) had adult T-cell leukemia/lymphoma (ATL) associated with human T-cell leukemia virus (HTLV-1). Patients with ATL had disease similar to that reported from southwestern Japan and the Caribbean. They had frequent skin lesions (60%), hypercalcemia (40%), and a rapid clinical course with a median survival of 1.3 years. The 35 HTLV-1-negative peripheral T-cell lymphomas (PTL) were similar to PTL in western countries, manifesting frequent visceral, cutaneous, and vascular tropisms. Marrow involvement was documented at presentation in 39% and Stage III/IV disease in 80% of the PTL patients. The histology of PTL usually expressed prominent reactive features which is distinct from that in ATL. Several subcategories could be defined: Hodgkin's-like PTL in nine patients, T-zone lymphoma in three, angioimmunoblastic lymphadenopathy-like lymphoma in one, Lennert's lymphoma in three, and angioinvasive lymphoma in four. Two HTLV-1-negative PTL had neoplastic cells with clover-shaped nuclei and were designated as ATL-like. Morphologic classification based on the modified Working Formulation showed prognostic correlation, with median survival of less than 6 months for large cell/immunoblastic PTL, compared with 5 years for patients with small/medium cell PTL. Both low- and high-grade PTL seem to represent an incurable disease. Classical cutaneous T-cell lymphoma (seven cases) is relatively unusual in Taiwan, compared with the frequency of PTL. Post-thymic T-cell malignancies in Taiwan include HTLV-1-positive and HTLV-1-negative diseases, both of which have a poor prognosis and resemble similar T-cell malignancies in the East and West.

Primary gastric peripheral T-cell malignant lymphoma with helper/inducer phenotype. First case report with a complete histological ultrastructural and immunochemical study

Primary gastrointestinal T-cell malignant lymphomas (T-ML) are very rare. In this case report we describe a primary gastric tumor with local lymph node involvement. On the basis of histologic, immunohistochemical, and electron microscopic studies, the authors classified this tumor as a pleomorphic T-ML, large cell variant with peripheral helper/inducer T-cell phenotype (Leu1/CD5+, Leu4/CD3+, Leu5/CD2+, Leu9/CD7+, and Leu3/CD4+). The extreme pleomorphism of lymphoma cells, the numerous giant cells, and the presence of tumor nodules with two or three concentric layers were the three striking morphologic features of our case. Tumor cells showed an inconstant but true positive staining with anti-LeuM1/CD15 and LeuM3/CD14 antibodies. Vimentin positivity could be related to the presence of intermediate filaments at ultrastructural level. Neuron-specific enolase reactivity was a peculiar but unexplained feature. Furthermore, the positivity of the surface markers Ki-1/CD30, anti-Tac/CD25 and HLA-DR, and the nuclear marker Ki-67 suggested an activation state and a high proliferative activity of the tumor cells. This study emphasizes the usefulness of combined pathologic methods in order to rule other diagnoses such as undifferentiated carcinoma, malignant melanoma, malignant histiocytosis, B-cell lymphoma and interdigitating reticulum cells sarcoma, in view of an extremely polymorph tumor proliferation. This is apparently the first completely documented case report of a primary gastric pleomorphic T-ML of peripheral T-cell origin.