Indolent CD8+ lymphoid proliferation of the ear: report of two cases and review of the literature

Indolent CD8+ lymphoid proliferation of the ear is a recently described cutaneous lymphoid proliferation that clinically presents with slow growing lesion(s) on the ear(s). In cases reported to date, there has been indolent clinical behavior and no evidence of systemic involvement. Characteristic histopathologic features include a non-epidermotropic diffuse dermal infiltrate of CD8+ T-lymphocytes with a lymphoblast-like appearance. T-cell clonality has also been observed. Herein, we present two patients who show clinical, histopathologic and immunophenotypic features similar to the original index cases described by Petrella et al. In addition, we review the literature regarding this unusual lymphoid proliferation and provide evidence that this entity represents a phenotypic variant of primary cutaneous CD4+ small/medium-sized pleomorphic T-cell lymphoma, a concept proposed by Beltraminelli et al. in 2009. Differentiation between this lymphoproliferative process and other more aggressive CD8+ lymphomas is essential in avoiding excessive treatment of a condition that combines worrisome histopathology with indolent clinical behavior.     

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.     

Indolent CD8‐positive lymphoid proliferation on the face: part of the spectrum of primary cutaneous small‐/medium‐sized pleomorphic T‐cell lymphoma or a distinct entity?

We report two cases of a CD8‐positive lymphoid proliferation presenting as solitary lesions on the ear and nose, respectively. Histopathologically, both cases were characterized by a diffuse non‐epidermotropic dermal proliferation of clonal medium‐sized CD8‐positive T‐lymphocytes with a lymphoblast‐like appearance, having cells with large folded nuclei, prominent nucleoli and ample amphophilic or pale eosinophilic cytoplasm. Staging procedures excluded systemic involvement, and both lesions were successfully treated with localised radiotherapy without evidence of recurrence after 12 and 24 months' follow up, respectively. Previously reported cases on the ear had similar clinicopathological and immunophenotypical features, and together raise the possibility of a distinct entity, an indolent CD8‐positive lymphoid proliferation. Suchak R, O'ConnorS, McNamara C, Robson A. Indolent CD8‐positive lymphoid proliferation on the face: part of the spectrum of primary cutaneous small‐/medium‐sized pleomorphic T‐cell lymphoma or a distinct entity?     

Indolent CD8-positive T-cell lymphoid proliferation of the ear: a report of two cases

The current classification of primary cutaneous T-cell lymphoma (CTCL) of the World Health Organization (WHO) includes primary cutaneous CD8-positive aggressive epidermotropic cytotoxic T-cell lymphoma as a provisional entity awaiting cumulative data. Recent reports identify CD3/CD8-positive clonal T-cell lymphoid proliferations arising in the ear and nose that behave indolently and therefore defy currently established subclassification. Here, we report two cases of clonal CD8-positive/granzyme-B-negative T-cell lymphoid proliferations that arose in the ear and behaved indolently. Collectively, these cases suggest that an additional category of cutaneous indolent CD8-positive T-cell lymphoma may be necessary among the existing classification schemes.     

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.     

Primary cutaneous CD4 positive small/medium T‐cell lymphoma with high proliferation index and CD30‐positive large lymphoid cells

Primary cutaneous CD4 positive small/medium pleomorphic T‐cell lymphoma (SMPTCL) represents a provisional subtype of primary cutaneous T‐cell lymphoma with indolent clinical course. A few aggressive fatal cases with increased proliferation rate and few infiltrating CD8 positive T‐cells have been reported. We describe a case of SMPTCL with an increased proliferation rate, admixed CD30‐positive large lymphoid cells, and few infiltrating CD8 positive T‐cells. The lymphoma cells were positive for CD3, CD4, CD2 and CD5, and negative for CD8. A subset of the lymphoma cells was positive for follicular helper T‐cell markers bcl‐6 and PD‐1. There were approximately 20% CD30‐positive large lymphoid cells, and Ki‐67 showed a moderately high proliferation rate (～40%), mostly in the large lymphoid cells. CD8 infiltrating T‐cells were few (<5%). The patient had an indolent disease with complete response to radiation therapy. To the best of our knowledge, this is the first reported case of SMPTCL with an increased proliferation rate and large CD30+ cells that followed an indolent clinical course.     

Indolent CD8+ lymphoid proliferation of the ear: A phenotypic variant of the small‐medium pleomorphic cutaneous T‐cell lymphoma?

Background: Recently, Petrella et al. described four patients with an unusual CD8+ lymphoid proliferation arising on the ear. These cases do not correspond clearly to any recognized category of cutaneous T-cell lymphoma (CTCL) described in the World Health Organization (WHO)/European Organization for Research and Treatment of Cancer (EORTC) 2005 classification.
Methods and Results: Three patients (all men; median age 64; range: 61-69) presented with plaques or small tumors localized on the ears. All lesions showed histopathologically a dense, diffuse infiltration of lymphocytes within the entire dermis without epidermotropism. Cytomorphology revealed predominance of medium-sized pleomorphic lymphocytes. Immunohistochemistry showed a cytotoxic phenotype (CD3 + /CD4 −/CD8 +). Polymerase chain reaction (PCR) analysis of the T-cell receptor (TCR)-gamma gene revealed a monoclonal rearrangement in two of three patients. Follow-up data of two patients were available; one is alive without skin or systemic manifestations of the disease after 28 months, whereas the other is alive with persistent skin disease after 7 months.
Conclusions: Our observation confirms that some patients present with a peculiar lymphoid proliferation of small-medium pleomorphic cytotoxic lymphocytes located on the ear, probably representing a phenotypic variant of the cutaneous small/medium pleomorphic T-cell lymphoma (CSMPTCL). These cases should not be misinterpreted as a high-grade cytotoxic lymphoma.     

Linfoma cutáneo primario T CD8+ tipo acral inducido por hipersensibilidad retardada persistente a pendientes de oro

Primary cutaneous CD8⁺ T-cell lymphoma has been included as a provisional entity within the new revised classification of lymphoid neoplasms of the World Health Organization in 2016¹. It was initially described as indolent CD8⁺ lymphoid proliferation of the ear² and a total of 29 cases of such neoplasm have been published in the literature so far. None of them have been linked to delayed contact hypersensitivity reactions. We present a case of acral type primary cutaneous lymphoma T CD8⁺ involving both earlobes clearly related with the prolonged use of gold earrings, confirmed with epicutaneous tests, histopathology, immunohistochemical and molecular studies. Auricular skin lesions were induced again with a provocation test with identical histopathologycal and the same clonality, confirming both the diagnosis of lymphoma and its induction by the antigenic stimulus of gold.     

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.     

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.     

Primary cutaneous CD4‐positive small/medium‐sized pleomorphic T‐cell lymphoproliferative disorder: Report of a case and review of the literature

Primary cutaneous small/medium‐sized T‐cell lymphoma (PCSM‐TCL), which was included in the World Health Organization ‐ European Organization for Research and Treatment of Cancer (WHO‐EORTC) classification for cutaneous lymphomas as a provisional entity in 2008, has recently been reclassified as primary cutaneous small/medium‐sized T‐cell lymphoproliferative disorder (PCSM‐TCLPD) because of its indolent behavior and uncertain malignant potential. Treatment with local therapies is usually curative, although there have been reports of aggressive, systemic disease. This spectrum of disease behavior evokes the consideration that this entity may actually be multiple diseases with a shared clinicopathologic features rather than a singular disease process with a variety of behaviors. PCSM‐TCLPD retained its designation as a provisional entity under the updated WHO‐EORTC guidelines; however, additional cases of PCSM‐TCLPD are needed to shed more light on this rare disorder.     

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.     

Gamma‐delta T‐cell lymphoma arising in a long‐standing cutaneous plaque

The precise classification and characterization of primary cutaneous gamma‐delta T‐cell lymphoma (PCGD‐TCL) has been hindered by clinical and morphologic features that overlap with other lymphomas, especially subcutaneous panniculitis‐like T cell lymphoma (SPTCL). The recent World Health Organization/European Organization for Research and Treatment of Cancer (WHO/EORTC) classification distinguishes the more aggressive PCGD‐TCL from the usually indolent SPTCL, however. We report a 30‐year‐old woman with an indurated violaceous plaque on the left cheek that had been present for several years. Biopsies showed a dense lymphocytic infiltrate involving the subcutis and dermis that consisted mostly of small and medium‐sized lymphocytes, some with irregular nuclear contours and dense chromatin. These cells were positive for TIA‐1, TCR‐gamma and CD8, but negative for beta‐F1 and granzyme‐B. Staging with positron emission tomography–computed tomography (PET/CT), CBC and bone marrow with flow cytometry identified lymphadenopathy as well as blood and marrow involvement by an abnormal TCRgd‐positive T‐cell proliferation (Ann Arbor Stage IV). The patient's history of a long‐standing lesion in this case is unusual, in that gamma‐delta T‐cell lymphomas are typically rapidly progressive neoplasms. As such, it raises the possibility of ‘transformation’ of a long‐standing inflammatory process into an overt lymphoma.     

Epidermotropic marginal zone lymphoma simulating mycosis fungoides†

Cutaneous lymphomas can usually be distinguished by architectural features, where most atypical lichenoid infiltrates implicate cutaneous T‐cell lymphoma (CTCL). We report a case of an 80‐year‐old man who presented with asymptomatic golden brown patches and diffuse pink papules on his trunk, buttocks and hips. Biopsies revealed a lichenoid infiltrate and areas of epidermotropism. Although the overall architectural pattern was compatible with mycosis fungoides, the lymphocytes had a more monocytoid and plasmacytoid appearance, and there were interspersed mature plasma cells. Immunohistological studies revealed that the pleomorphic lymphocytes were predominantly B cells (CD20\+ and CD79a\+) with a subpopulation of smaller bland T cells (CD3\+). Moreover, the B‐cell immunophenotype was compatible with marginal zone differentiation (bcl‐2+, bcl‐6?, CD10? and CD5?) and showed a lambda light chain restriction, confirming monoclonality. These findings were diagnostic for cutaneous marginal zone B‐cell lymphoma (MZL) with epidermotropism an entity which has only been reported twice in the literature, once in the setting of primary cutaneous disease, and once as cutaneous involvement of systemic disease. This case illustrates a rare pattern of cutaneous MZL, and underscores the importance of immunophenotypic characterization of cutaneous lymphomas in order to prevent the misdiagnosis of a CTCL.     

Primär kutane CD4+ klein‐ bis mittelgroßzellige pleomorphe T‐Zell‐Lymphoproliferation: Wo stehen wir? Eine systematische Übersicht

Primary cutaneous CD4+ small/medium pleomorphic T‐cell lymphoproliferative disorder (PCSMP‐TLPD) is a provisional entity with uncertain malignant potential according to the latest revision of the WHO classification for lymphoid neoplasms. We conducted a systematic literature review of all previously reported cases of PCSMP‐TLPD to highlight their typical and atypical features. The main features of PCSMP‐TLPD and its possible clinicopathologic overlap with similar disorders are also discussed. It is hoped that this review will provide a useful outline of this condition and the most important differential diagnoses. Finally, we recommend a rigorous consensus among cutaneous lymphoma experts in drafting diagnostic criteria and the best case definition.     

Extragenital lichen sclerosus et atrophicus mimicking cutaneous T‐cell lymphoma: report of a case

Early lesions of lichen sclerosus et atrophicus (LSA) may present as a mild lichenoid tissue reaction, occasionally together with basilar epidermotropism, mimicking early cutaneous T‐cell lymphoma, mycosis fungoides (MF) variant. We report a case of extragenital LSA in which both histological patterns were present in the same clinically homogenous and stable lesion. A 27‐year‐old man presented with a history of white atrophic plaques on the trunk. A biopsy of an abdominal lesion revealed epidermal thinning, a superficial perivascular lymphoid cell infiltrate with focal epidermotropism, mild nuclear atypia and perinuclear halos. Immunophenotyping showed decreased CD5 and CD7, with a slight predominance of CD8‐positive T‐lymphocytes. All these changes were suggestive of MF. However, a repeat biopsy 3 months later from the same stable plaque revealed features diagnostic of LSA. LSA mimicking early MF histologically has been reported in genital skin. Conversely, MF may clinically and histopathologically resemble LSA. With gene rearrangement studies, clonal proliferation may not be detected in early MF but has been reported to occur in LSA. Awareness of the histopathologic spectrum of LSA within a stable plaque is important to avoid a potential diagnostic pitfall, and should prompt a repeat biopsy. Suchak R, Verdolini R, Robson A and Stefanato CM. Extragenital lichen sclerosus et atrophicus mimicking cutaneous T‐cell lymphoma: report of a case.     

Acneiform primary cutaneous CD4‐positive small/medium pleomorphic T‐cell lymphoma with prominent necrosis

Primary cutaneous CD4‐positive small/medium pleomorphic T‐cell lymphoma (SMPTCL) is an indolent form of cutaneous lymphoma that usually presents in solitary fashion and is histopathologically characterized by nodular infiltration of small‐ to medium‐sized pleomorphic T‐cells. We report the case of a patient who presented with a 5‐year history of acneiform lesions on his face. Histopathologic examination of two lesions revealed a nodular infiltrate of small to medium‐sized lymphocytes with necrosis in the dermis. The proliferating cells were positive for CD2, CD3 and CD4 and negative for CD8, CD30 and CD56. They were positive for TIA‐1 and negative for perforin and granzyme B. The Ki67 proliferation index was approximately 10%. The neoplastic cells expressed programmed death‐1 and lacked expression of CXCL‐13, bcl‐6 and CD10. In situ hybridization for Epstein–Barr virus‐encoded RNA yielded a negative result. T‐cell receptor gene rearrangement showed identical T‐lymphocyte monoclonality in both lesions. In brief, we report a rare case of acneiform SMPTCL with prominent necrosis.     

Cutaneous gamma‐delta T‐cell lymphoma with central nervous system involvement: report of a rarity with review of literature

Primary cutaneous gamma‐delta (γδ) T‐cell lymphoma is an extremely rare and aggressive variant of cutaneous lymphoma. Central nervous system (CNS) involvement, a rare finding, and hemophagocytic syndrome are two complications that are commonly fatal. We describe a 58‐year‐old patient presenting with skin plaque who subsequently developed subcutaneous nodules diagnosed as cutaneous T‐cell lymphoma (CTCL), clinically resembling ‘mycosis fungoides’. The patient was treated with repeat topical radiation therapies but had frequent relapsed disease. Approximately 4.5 years after, the patient presented with third and sixth cranial nerve palsies and was found to have CNS involvement by lymphoma per positron emission tomography—computed tomography (PET/CT) and a biopsy of foramen magnum. Phenotypically, the tumor cells were CD3(+)/CD4(?)/CD8(?)/CD7(+)/CD5(?)/CD30(?)/TCRαβ(?)/TCRγδ(+). Despite aggressive strategies taken, the patient expired 3 months after the diagnosis of the CNS lesion. A retrospective investigation proved the original CTCL to be γδ T‐cell in origin, confirming an indolent cutaneous γδ T‐cell lymphoma with eventual CNS manifestation. We present this case to draw attention to the entity, which can occasionally present with misleading histopathologic and clinical features. In addition, we provide a review of the literature to summarize clinical and pathologic features of the reported similar cases.     

Indolent course of cutaneous gamma‐delta T‐cell lymphoma

Cutaneous gamma‐delta T‐cell lymphoma (γδTCL) is a rare malignancy that typically displays an aggressive clinical course. We present an unusual case of a 57‐year‐old woman with a 3‐year history of lower extremity nodules. Histopathologic, immunophenotypic and molecular genetic studies revealed a clonal, predominantly pannicular gamma‐delta T‐cell infiltrate, leading to a diagnosis of cutaneous γδTCL. The clinical course was characterized by rapid improvement within months of starting systemic corticosteroids, with relapse in ulcerations but no new lesions more than 3 years after onset of disease. Our case and seven previously reported patients with indolent and relatively localized cutaneous γδTCL provide evidence that not all cases of this entity carry a poor prognosis. This indolent subset adds complexity to treatment of cutaneous γδTCL.     

Primary cutaneous γδ T-cell lymphoma with unusual immunophenotype: A case report and review of published work

Primary cutaneous γδ T-cell lymphoma (CGD-TCL) is a rare form of primary cutaneous lymphoma. The histopathological features of CGD-TCL are still unclear because of its rarity. Here, we report a case of a 77-year-old Japanese man who presented with a 9-month history of erythematous plaques on his left forearm. Skin biopsy specimens revealed the infiltration of atypical medium/large-sized lymphocytes from the epidermis to the deep dermis. Atypical lymphocytes were positive for CD3, CD5, CD8 and Vδ1, and negative for CD4, CD7, CD56, EBER-ISH, intracellular antigen-1, granzyme B and perforin. CD30 was partially expressed. We also reviewed 246 cases of CGD-TCL from the published work. CD4⁻CD8⁻ double-negative cases were 113 of 196 cases (57.6%), followed by CD4⁻CD8⁺ cases (52/196, 26.5%). CD5 was expressed in 25.8% of the cases (34/132). At least one cytotoxic molecule marker was expressed in 150 of 160 cases (93.8%). Some cases showed an indolent clinical course, especially in mycosis fungoides-like CGD-TCL cases. CD5 positivity and lack of cytotoxic molecule expression could be associated with a better prognosis. In addition, CD30 expression was found in approximately half of CGD-TCL cases (51/112 cases), suggesting that brentuximab vedotin could be a good treatment option for such patients. Further studies with more cases with detailed clinical and pathological information are necessary to elucidate the etiology and prognostic markers of this entity.