Extrafacial indolent CD8‐positive cutaneous lymphoid proliferation with unusual symmetrical presentation involving both feet

Indolent CD8+ cutaneous lymphoid proliferation represents a recently described entity among cutaneous T‐cell lymphomas that typically presents with solitary skin lesions on the face or at acral sites and usually follows an indolent clinical course. Histopathologically, this entity is characterized by a dense dermal infiltrate of non‐epidermotropic, small‐ to medium‐sized pleomorphic CD8+ T‐cells of the non‐activated cytotoxic phenotype showing a clear‐cut grenz zone and a low proliferation index. Distinction from otherwise aggressive T‐cell lymphomas bearing a cytotoxic CD8+ phenotype is fundamental. We herein present an unusual case of indolent CD8+ cutaneous lymphoid proliferation presenting in bilateral symmetrical distribution on both feet and lacking the otherwise described grenz zone. Our case widens the spectrum of possible clinical and histomorphological variations of this entity. Taking into account the distinctive and unique clinical and microscopic features of all hitherto published cases of indolent CD8+ cutaneous lymphoid proliferation we suppose that this lymphoma subtype has to be included as a new and distinct entity in the World Health Organisation (WHO)‐/European Organisation for Research and Treatment of Cancer (EORTC)‐classification of cutaneous lymphomas.     

Immunophenotypic shift of CD4 and CD8 antigen expression in primary cutaneous T‐cell lymphomas: a clinicopathologic study of three cases

Primary cutaneous T‐cell lymphomas (CTCL) comprise a heterogeneous group of neoplasms with diverse clinical behavior. Mycosis fungoides (MF) is the most common type of CTCL. Immunophenotypical shift during progression of the disease is a rare event and its significance is unknown. We present three primary CTCL cases that showed an immunophenotypical shift and poor prognosis. Conventional hematoxylin/eosin and immunohistochemical‐stained sections were examined in all the cases. Molecular analysis for rearrangement of the T‐cell receptor (TCR) gene was performed in two cases. One case was classified as MF, while the other two lacked epidermotropism, and were considered primary cutaneous peripheral T‐cell lymphoma (PTCL), NOS. Two cases were CD3+/CD4+ and one case was CD3+/CD8+ at diagnosis. The first two patients suffered many relapses and eventually, new CTCL lesions with a CD3+/CD8+ phenotype were observed. Both cases revealed identical clonal TCR rearrangements on the initial and late lesions, supporting the interpretation of a single clonal proliferation with different phenotypes. The third case progressed with skin recurrences and pulmonary lesions with a predominant CD3+/CD4+/CD8? phenotype. All cases manifested poor prognosis and two patients died of lymphoma. Immunophenotypical shift between CD4 and CD8 in CTCL seems to be a rare phenomenon that may be associated with disease progression.     

Histopathological aspects and differential diagnosis of CD8 positive lymphomatoid papulosis

Lymphomatoid papulosis (LyP) belongs to CD30+ lymphoproliferative disorders with indolent clinical course. Classic histological subtypes, A, B and C are characterized by the CD4+ phenotype, while CD8+ variants, most commonly classified as type D, were reported in recent years. We present 14 cases of CD8+ LyP. In all patients, self‐resolving or treatment‐sensitive papules were observed. Of 14 cases 7 produced results with typical microscopic features of LyP type D mimicking primary cutaneous aggressive epidermotropic CD8+ T‐cell lymphoma. The infiltration pattern in 4 of 14 cases were consistent with classic LyP type B, without CD30 expression in two cases, resembling mycosis fungoides (MF). The morphology of 2 of 14 cases shared a certain consistency with classic type A and C, lacking eosinophils and neutrophils. Extensive folliculotropism characteristic to type F was observed in 1 of 14 case. Significant MUM1 and PD1 expression were detected in 2 of 14 and 3 of 14 cases, respectively. We concluded that CD8+ LyP may present with different histopathological features compared with type D, similar to CD4+ LyP variants. Differential diagnoses include CD8+ papular MF, folliculotropic MF and anaplastic large cell lymphoma in addition to primary cutaneous aggressive epidermotropic T‐cell lymphoma. We emphasise that rare CD8+ LyP cases may exist with CD30‐negativity.     

A review of the solitary cutaneous T‐cell lymphomas

Cutaneous T‐cell lymphomas (CTCL) account for almost 65‐92% of all cutaneous lymphomas, many of which usually present with multiple lesions. However, a number of well‐recognized and rare types of CTCL, including mycosis fungoides, can present in isolated fashion. These solitary lesions often run a relatively indolent clinical course but often pose diagnostic difficulties. We review histopathologically challenging solitary cutaneous T‐cell lymphomas, including criteria for diagnosis, clinical course and prognosis, particularly for primary cutaneous CD4+ small/medium pleomorphic lymphoma and indolent CD8+ lymphoid proliferation of acral sites. In addition, we suggest an algorithm and nomenclature to aid in the diagnosis of such problematic lesions.     

Cutaneous CD30‐positive lymphoproliferative disorders with CD8 expression: a clinicopathologic study of 21 cases

Lymphomatoid papulosis (LyP) and cutaneous anaplastic large cell lymphoma (ALCL) belong to the spectrum of cutaneous CD30+ lymphoproliferative disorders, an indolent form of T‐cell lymphoproliferative disease. We reviewed 21 cases of CD30+ lymphoproliferative lesions expressing cytotoxic profile (CD8+). Seven cases of cutaneous ALCL, 2 cases of systemic ALCL involving the skin, and 12 cases of LyP. The cases of LyP were predominated by small lymphocytes exhibiting a prominent epidermotropic pattern consistent with either type B or type D LyP. Four cases showed co‐expression of CD56. The ALCL cases included myxoid features, pseudoepitheliomatous change, and an intravascular component. In all cases that were primary in the skin an indolent clinical course was seen while one patient with systemic myxoid ALCL is in remission following systemic multiagent chemotherapy. The paucity of other neutrophils and eosinophils and concomitant granulomatous inflammation were distinctive features in cases of type B and type D LyP. CD30 and CD45 Ro positivity and a clinical course typical of LyP were useful differentiating features from an aggressive cytotoxic CD8+ T cell lymphoma. In all cases that were primary in the skin an indolent clinical course was observed. CD30 and CD45 Ro positivity and a clinical course typical of LyP were useful in preventing a misdiagnosis of an aggressive cytotoxic CD8+ T cell lymphoma.     

Primary cutaneous anaplastic large cell lymphoma

Primary cutaneous anaplastic large cell lymphoma (PC‐ALCL) is a CD30+ lymphoproliferative disorder (LPD) of the skin with a relatively good prognosis in the absence of high‐stage disease. CD30+ LPDs comprise approximately 25%‐30% of primary cutaneous lymphomas and as a group represent the second most common clonal T‐cell neoplasm of the skin behind mycosis fungoides. Diagnosis of PC‐ALCL relies strongly on clinicopathologic correlation given the potential morphologic, clinical and molecular overlap with the other cutaneous CD30+ LPD, lymphomatoid papulosis, and more aggressive hematolymphoid neoplasms.     

Acitretin combined with NB‐UVB in the treatment of cutaneous CD30‐positive anaplastic large cell lymphoma

Cutaneous CD30⁺ lymphoproliferative disorders represent a spectrum of skin lymphatic reticular proliferative diseases, including lymphomatoid papulosis (LYP), primary cutaneous anaplastic large cell lymphoma (PC‐ALCL), and borderline lesions between them. Although they all express CD30 as a phenotypic marker and share overlapping immunophenotypic features, they differ in clinical manifestations, pathological features, treatment, and prognosis. LYP is a kind of benign disease characterized by recurrent papules and nodules, and may spontaneously regress. PC‐ALCL presents with solitary tumor or local grouped nodules characterized by large T‐cells and may completely or partially resolve in fewer than half of cases. We reported a case of patient with clinical manifestation and pathologic features consistent with LYP in its early stages, which later turned into PC‐ALCL. This patient was treated with acitretin combined with NB‐UVB and had an obvious response.     

Childhood mycosis fungoides with a CD8+ CD56+ cytotoxic immunophenotype

Primary cutaneous T‐cell lymphomas mostly occur in patients of middle and higher age. Their rarity and an oftentimes atypical clinical presentation in childhood as well as the reluctance of taking biopsies in children are reasons for a delayed diagnosis. We report the case of an 11‐year‐old boy with a 7‐year history of slowly progressive CD8+CD56+ mycosis fungoides of the cytotoxic immunophenotype. His trunk and extremities were affected by extensive pale‐erythematous patches and plaques with fine scaling. In addition, several poikilodermatous lesions were present on his thighs. Improvement was achieved by topical mometasone furoate treatment. On the basis of our observation, a brief review on cutaneous T‐cell lymphomas in childhood and on CD8+ subtypes in particular is given. Clinicopathological correlation is crucial for establishing the correct diagnosis and for estimation of the prognosis.     

The new World Health Organization-European Organization for Research and Treatment of Cancer classification for cutaneous lymphomas: a practical marriage of two giants

Following consensus meetings of the two parent organizations, a new World Health Organization-European Organization for Research and Treatment of Cancer (WHO-EORTC) classification for primary cutaneous lymphomas has recently been published. This important development will now end the ongoing debate as to which of these was the preferred classification. The new classification will facilitate more uniformity in diagnosis, management and treatment of cutaneous lymphomas. In particular, it provides a useful distinction between indolent and more aggressive types of primary cutaneous lymphoma and provides practical advice on preferred management and treatment regimens. This will thereby prevent patients receiving high-grade treatment for low-grade biological disease. This review focuses on those diseases which have found new consensus agreement compared with the original WHO and EORTC classifications. In cutaneous T-cell lymphomas, these include folliculotropic mycosis fungoides, defining features of Sézary syndrome, primary cutaneous CD30+ lymphoproliferative disorders (primary cutaneous anaplastic large cell lymphoma, lymphomatoid papulosis and borderline lesions) and subcutaneous panniculitis-like T-cell lymphoma. Primary cutaneous CD4+ small/medium-sized pleomorphic T-cell lymphoma, primary cutaneous aggressive epidermotropic CD8+ T-cell lymphoma and cutaneous gamma/delta T-cell lymphoma are allocated provisional entry status and thereby afford better definitions for some cases of currently unspecified primary cutaneous peripheral T-cell lymphoma. In cutaneous B-cell lymphomas, diseases which have found new consensus agreement include primary cutaneous marginal zone B-cell lymphoma, primary cutaneous follicular centre lymphoma, primary cutaneous diffuse large B-cell lymphoma, leg type and primary cutaneous diffuse large B-cell lymphoma, other. CD4+/CD56+ haematodermic neoplasm (early plasmacytoid dendritic cell leukaemia/lymphoma) now appears as a precursor haematological neoplasm and replaces the previous terminology of blastic NK-cell lymphoma. Other haematopoietic and lymphoid tumours involving the skin, as part of systemic disease, will appear in the forthcoming WHO publication Tumours of the Skin. The new classification raises interesting new problems and questions about primary cutaneous lymphoma and some of these are discussed in this article. It is, however, a splendid signpost indicating the direction in which research in cutaneous lymphoma needs to go. In the interim, we have an international consensus classification which is clinically meaningful.     

Dermal infiltrates of cutaneous T‐cell lymphomas with epidermotropism but not other cutaneous lymphomas are abundant with langerin+ dendritic cells

Background The Langerhans cell (LC) hypothesis suggests that cutaneous T‐cell lymphomas (CTCL) are diseases of chronic T‐cell stimulation by LC‐mediated antigen presentation. Objective To investigate a broad panel of CTCL and cutaneous B‐cell lymphomas (CBCL) for the spatial association of langerin⁺ dendritic cells (DC) with T and B cells in the skin, respectively. Methods Fifty‐five specimens of CTCL and 10 of CBCL were double‐stained with monoclonal antibodies against langerin and CD3 or CD20, respectively, and evaluated by confocal laser scan microscopy. Results Dermal infiltrates in mycosis fungoides (n = 38), primary cutaneous CD4+ small/medium‐sized pleomorphic T‐cell lymphoma (n = 3) and primary cutaneous peripheral T‐cell lymphoma, unspecified (n = 3) were characterized by a high frequency of dermal langerin⁺ DCs. These cells were exclusively present in the malignant infiltrates. No direct co‐localization of CD3 and langerin could be resolved. Dermal langerin⁺ cells were detected only in one of six primary cutaneous anaplastic large cell lymphomas (C‐ALCL), characterized by epidermotropism. In other C‐ALCL cases (five of six), in lymphomatoid papulosis (n = 3), subcutaneous panniculitis‐like T‐cell lymphoma (n = 2), and all variants of CBCL no dermal langerin⁺ DCs could be found. Conclusions Langerin⁺ DCs are abundant in the dermal infiltrates of T‐cell lymphomas with specific involvement of the epidermis. This might indicate that immature LC and neoplastic T cells interact and gives rise to further studies to characterize the phenotype of the langerin⁺ cell population described here and its role in the pathology of CTCL.     

Relative frequency of the different types of cutaneous T cell and natural killer cell lymphomas in Korea based on the proposed WHO classification and the EORTC classification

The R.E.A.L. classification was largely adopted recently by the proposed WHO classification. The usefulness of this classification in cutaneous T cell and natural killer (NK) cell lymphomas in Korea was evaluated compared to that of the European Organization for Research and Treatment of Cancer (EORTC) classification. Overall, 78 patients with cutaneous T cell and NK cell lymphomas were diagnosed in Asan Medical Center in the 1990's. The clinical records, slides of H&E and immunohistochemical stainings were reviewed. By the proposed WHO classification, mycosis fungoides (20 cases), lymphomatoid papulosis (13 cases), nasal type NK/T-cell lymphoma (10 cases), CD30+ anaplastic large cell lymphoma (8 cases), subcutaneous panniculitis-like T-cell lymphoma (6 cases), peripheral T-cell lymphoma, unspecified (3 cases), Sézary syndrome (1 case) and blastic NK cell lymphoma (1 case) comprised the primary cases. Secondary or undetermined cases included peripheral T-cell lymphoma, unspecified (10 cases), nasal type NK/T-cell lymphoma (5 cases), and angioimmunoblastic T-cell lymphoma (1 case). EORTC classification for cutaneous T cell and NK cell lymphomas did not include nasal and nasal type NK/T-cell lymphomas, unspecified non-pleomorphic T-cell lymphoma, undetermined cases among primary or secondary ones and some rare types of skin lymphomas which can be classified by WHO. The WHO classification is more useful for skin lymphomas in Korea since it encompassed all the various types of skin T cell and NK cell lymphomas in Korea.     

Cutaneous lymphomas showing prominent granulomatous component: clinicopathological features in a series of 16 cases

Background  The presence of a prominent granulomatous tissue reaction in skin biopsies from primary cutaneous or systemic malignant lymphomas with secondary cutaneous involvement is a rare but well-known phenomenon.
Objective  This paper aims to characterize and study a series of cutaneous lymphomas showing a prominent granulomatous component.
Patients and methods  The clinical, histopathological and evolutive features of granulomatous variants of mycosis fungoides (5 patients, 2 of them associating 'granulomatous slack skin' features), Sézary syndrome (1 patient), CD30⁺ cutaneous T-cell lymphoma (2 patients), CD4⁺ small/medium pleomorphic cutaneous T-cell lymphoma (1 patient), primary cutaneous B-cell lymphoma (3 patients) and peripheral T-cell lymphoma with secondary epithelioid granulomatous cutaneous involvement (4 patients) were reviewed.
Results  The observed features were clinically non-distinctive. Only those cases presenting with granulomatous slack skin features were clinically suspected (2 patients). Non-necrotizing granulomata (11 patients) and granuloma annulare-like (4 patients) were the most frequently observed histopathological patterns. In five cases, no diagnostic lymphomatous involvement was initially observed. From our series, no definite conclusions regarding prognosis could be established.
Conclusion  The diagnosis of cutaneous lymphoma may be difficult when a prominent cutaneous granulomatous inflammatory infiltrate obscures the true neoplastic nature of the condition. However, the presence of concomitant lymphoid atypia may help to suspect the diagnosis. In doubtful cases, the clinical evolution and the demonstration of a monoclonal lymphoid B- or T-cell population may lead to a definite diagnosis.

Conflicts of interest

None declared.     

Skin is the frequent site for involvement of peripheral T-cell and natural killer cell lymphomas in Korea

We have studied the clinicopathological features of 19 Korean cases of peripheral T-cell and natural killer (NK) cell lymphomas, not including mycosis fungoides. Primary cutaneous involvement was demonstrated in eight of these 19 cases, and we recognized four clinicopathologic subtypes among these eight patients: nasal type NK/T cell lymphoma, three cases; primary cutaneous CD30 positive anaplastic large cell lymphoma, two cases; subcutaneous panniculitis-like T-cell lymphoma, one case; lymphoma with hydroa vacciniforme-like cutaneous lesions, two cases. We did not, however, encounter any cases of HTLV-associated adult T-cell lymphoma/leukemia, which is common in Taiwan and Japan. EBV-associated lymphoma is the most prominent type of peripheral T-cell and NK cell neoplasm involving the skin in Korea.     

Primary cutaneous T cell lymphomas: photochemotherapy immunomodulation with analysis of the inflammatory‐expansive cellular dynamic

Primary cutaneous T cell lymphomas (CTCLs) are characterized by hyperproliferation of malignant CD4+ T cells with primary localization on the skin. The common characteristics are the migration of the malignant mature T‐lymphocytes into the epidermis, with hyperproliferation of malignant CD4+ T cells and epidermotropism. Sézary syndrome (SS) is the leukemic variant. It was established that CTCLs arise from a clonal expansion of CD4+ T cells with an identical rearrangement of the T cell receptor. The purpose of this study was to evaluate the immunomodulation effect of photochemotherapy‐A (psoralen plus ultraviolet A (PUVA)). Pre‐ and post‐PUVA punch skin biopsies of nine patients were stained immunohistochemically for CD34+, CD8+, CD7+, CD16+, CD56+, CD1a+, Bcl2+, p53+, CD45RA+, and CD45RO+ cells. The results showed a pre‐PUVA cells/mm² without significant difference among expansive or reactive cells. Post‐PUVA analysis showed a significant decrease in the mean of expansive‐reactive cells. PUVA immunomodulated decreasing cellular infiltrate. These findings could contribute to the comprehension of how PUVA acts. We achieved ectoscopic clearance of the lesions, although post‐PUVA, there still was a mononuclear pathological infiltrate. This result demonstrates that the PUVA treatment should only be withheld when the histological analysis is normal.     

Primary cutaneous γδ-T-cell lymphoma treated with low-dose methotrexate and narrowband ultraviolet B irradiation: report of a case with testicular involvement

Primary cutaneous γδ-T-cell lymphoma (CGD-TCL) is a rare entity of cutaneous T-cell lymphomas (CTCL) and is characterized by tumoral growth of mature γδ-T-cell expressing cytotoxic molecules. The prognosis of CGD-TCL is generally worse than other CTCL. However, relatively indolent patch/plaque lesions have been described suggesting the heterogeneous nature of this entity. Here, we present a case of CGD-TCL with various skin manifestations, such as erythematous plaques/tumors and subcutaneous panniculitis-like lesions. During the follow up, testicular involvement was detected, which was surgically removed. Histopathology showed mixed features from epidermotropism, dermal infiltration and subcutaneous panniculitis-like lesions depending on the clinical manifestations. The tumor cells were positive for CD3 and revealed cytotoxic markers, TIA-1 and perforin, but not for CD4, CD8, CD20, CD56, TCRβF1 or EBER. Topical glucocorticoid ointment, narrowband ultraviolet B (NB-UVB) irradiation and low-dose methotrexate (MTX) were effective to control these skin lesions. No visceral involvement was detected thereafter. While CGD-TCL is usually associated with poor prognosis, it seems to be composed of various clinical manifestations, and NB-UVB and low-dose MTX could be a choice for indolent patch/plaque and possibly nodular lesions, especially for the aged.     

Composite cutaneous lymphoma of diffuse large B‐cell lymphoma‐leg type and subcutaneous panniculitis‐like T‐cell lymphoma

Composite lymphoma (CL) is a rare disease defined by the occurrence of two distinct lymphomas within a single tissue at the same time. We present the case of an 89‐year‐old male with a clinical history of immunoglobulin M monoclonal gammopathy of undetermined significance. The patient presented cutaneous eruption of nodules on the right bottom and arm. An excisional biopsy revealed cutaneous infiltration composed of two components. The first one consisted of large B‐cells with CD20+/MUM1+/BCL2+ phenotype whereas the second one involved the subcutaneous fat in a panniculitic manner, and was CD3+/CD8+/granzyme B+/TCRβF1+. The final diagnosis was CL of primary cutaneous large B‐cell lymphoma‐leg type (PCLBCL‐leg type) and subcutaneous panniculitis‐like T‐cell lymphoma (SPTCL). We report and characterize for the first time coexistent PCLBCL‐leg type and SPTCL in a patient.     

Pilotropic T-cell lymphoma without mucinosis: 5 new cases]

BACKGROUND: Pilotropic cutaneous T-cell lymphomas without mucinosis are rare, with 27 cases previously reported. Diagnosis and classification may be difficult. The clinical course and histopathological and immunohistochemical findings in 5 patients are described. PATIENTS AND METHODS: Patients were selected from the register of the French Study Group for cutaneous lymphomas. The criteria for inclusion were clinical pilofollicular manifestations and histological features of pilotropic T-cell lymphoma without mucinosis. RESULTS: Five patients were selected. The most frequent clinical manifestations were follicular keratosis, alopecia and follicular papules. Typical lesions of mycosis fongoides were present for several years in 3 patients, and lymphomatoid papulosis preexisted in one patient. Histopathological analysis showed an infiltrate composed of CD3+ and CD4+ atypical lymphocytes involving the follicular epithelium with alteration of the hair follicle walls. Epidermotropism was associated with pilotropism and situated near the follicular lesions or farther apart. Alcian blue stains results were negative in all specimens. PCR studies showed the presence of a T-cell clone in the skin lesions in all cases. COMMENTS: Diagnosis of pilotropic cutaneous T cell lymphomas without mucinosis may be difficult in case of discrete epidermotropism, minimal infiltrate or involvement of the follicular epithelium. Pilotropism could define a particular variant of T-cell lymphomas.     

Cutaneous lymphomas other than mycosis fungoides in Singapore: a clinicopathological analysis using recent classification systems

BACKGROUND: Cutaneous lymphomas other than mycosis fungoides (MF) are a heterogeneous group with wide variations in clinical presentation, biological behaviour and prognosis. New classification systems have been designed or proposed in recent years, with well-defined disease entities and emphasis on the importance of site. OBJECTIVES: This study aims to analyse a series of non-MF lymphomas in an institution-based dermatological setting in Singapore, based on the European Organization for Research and Treatment of Cancer (EORTC) classification and the World Health Organization (WHO) classification. A secondary objective is to highlight the clinical utility of both classification systems. PATIENTS AND METHODS: Forty cases diagnosed over a 12-year period were examined by immunohistochemistry with antibodies targeting CD3, CD4, CD5, CD8, CD20, CD30, CD43, CD45RO, CD56 and CD68 in paraffin-embedded specimens. The immunohistological diagnosis was correlated with the clinical presentation and staging investigations for the final diagnosis and the course of disease recorded. RESULTS: Non-MF T-cell lymphomas presenting in the skin comprised 31 cases (78%) and were 3(1/2) times more common than B-cell lymphomas, which comprised nine cases (22%). The common subtypes were lymphomatoid papulosis, CD30+ large cell cutaneous T-cell lymphoma and subcutaneous panniculitis-like T-cell lymphoma. The commonly ascribed B-cell pattern with infiltrates in the mid and deep dermis and perivascular spaces was seen in 60% of T-cell lymphomas. Overall, there were equal numbers of primary cutaneous T-cell lymphomas and those due to concurrent or secondary cutaneous lymphoma. Five of six cases of subcutaneous panniculitis-like T-cell lymphoma had concurrent cutaneous and systemic involvement and their median survival was 7 months. CONCLUSIONS: The predominance of cutaneous T-cell lymphomas in this case series closely matched that reported from east Asia; cutaneous B-cell lymphomas are much less common than in Europe. The EORTC classification, which is designed only for primary cutaneous lymphomas, should be used in conjunction with the WHO classification because of the high prevalence of cutaneous lymphomas as the secondary site of disease from systemic lymphoma. In addition, subcutaneous panniculitis-like T-cell lymphoma is a primary cutaneous lymphoma where systemic involvement is common at initial presentation. We propose full immunophenotyping and complete clinical evaluation with staging investigations for all patients presenting with cutaneous lymphomas other than MF.     

Phenotypic evolution in a case of peripheral T‐cell lymphoma suggests the presence of tumor heterogeneity

Peripheral T‐cell lymphoma (PTCL), not otherwise specified (NOS), represents a heterogeneous group of nodal and extranodal lymphomas that express a variety of T‐cell antigens indicative of mature T‐cell lineage. Most cases of PTCL express CD4 and lack CD8 expression and have a T‐helper immunophenotype. Although the immunophenotype of PTCL is usually stable over time, immunophenotypic switch or evolution from T‐helper to T‐suppressor or vice versa has been rarely reported. Herein, we report a patient who presented with nasal PTCL, NOS, that was CD8+ and negative for Epstein–Barr virus, with concurrent skin lesions that had a CD8+/TIA‐1+ T‐cell immunophenotype. Patient received multi‐agent chemotherapy and matched unrelated donor stem cell transplant, and subsequently suffered a cutaneous relapse with a CD4+/TIA‐1(?) immunophenotype. Molecular analysis of the neoplasm biopsied at presentation showed one monoclonal T‐cell receptor gamma gene rearrangement, and a second oligoclonal peak. At the time of CD4‐positive recurrence, the oligoclonal peak was rather prominent, suggesting that the emergence of this peak is related with the phenotypic evolution from CD8+ to CD4+ predominant. These results highlight the utility of sequential immunophenotypic and molecular analysis of PTCL cases at the time of relapse to better understand the mechanisms of disease.     

Primary cutaneous acral CD8 positive T‐cell lymphoma with extra‐cutaneous involvement: A long‐standing case with an unexpected progression

Primary cutaneous acral CD8+ T‐cell lymphoma (acral CD8+ TCL) is a new provisional entity characterized by acral skin lesions and an indolent course. We describe an extraordinary case characterized by relapsed nodules with CD8+ cytotoxic infiltrates on the left ear. After 35 years, the skin lesions spread to other acral sites, and a mass with the same histological features as the other skin lesions appeared on the nose. Multiple courses of chemotherapy led to stable disease. Histological examinations carried out at different times showed the gradual transformation of the neoplastic cells, with an increased proliferation index. Genomic analysis revealed losses in the regions harboring the genes involved in cell cycle control. This is the first case of an acral CD8+ TCL with a very long history of indolent nodular lesions progressing to extra‐cutaneous sites.