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.     

Systemic panniculitis‐like T‐cell lymphoma with involvement of mesenteric fat and subcutis

Subcutaneous panniculitis‐like T‐cell lymphoma (SPTCL) is an uncommon non‐Hodgkins primary cutaneous lymphoma that typically presents as subcutaneous nodules on the extremities or trunk. Here, we report an unusual case of systemic panniculitic T‐cell lymphoma with predominantly mesenteric extra‐cutaneous involvement and an aggressive clinical course with histopathologic and immunophenotypic features that mimic SPTCL. This case serves to expand the body of literature regarding systemic SPTCL‐like disorders with prominent extra‐cutaneous involvement.     

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.     

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.     

Oral bexarotene for post‐transplant cutaneous T‐cell lymphoma

Organ transplant recipients receiving immunosuppression have an increased risk of developing post‐transplant lymphoproliferative diseases (PTLDs). Traditionally, PTLDs refer to Epstein‐Barr virus (EBV)‐induced B‐cell lymphoma. However, post‐transplant T‐cell lymphoma may also occur and tends to have a poorer response to reduced immunosuppressive therapy. As such, additional therapy is often needed for post‐transplant T‐cell lymphoma, including post‐transplant cutaneous T‐cell lymphoma (PT‐CTCL). We present only the third case of PT‐CTCL occurring after liver transplantation. The patient was diagnosed with stage IB mycosis fungoides (MF). His lesions were refractory to multiple skin‐directed therapies, and so he was given oral bexarotene 150 mg daily and his oral tacrolimus dose was decreased to 2 mg daily. Remarkably, his MF patches have demonstrated a complete response to oral bexarotene 75 mg daily without recurrence over 11 years of follow‐up. He developed hypertriglyceridemia with bexarotene 150 mg, so his dose was decreased to 75 mg, without loss of response. Our report is the second to describe PT‐CTCL demonstrating a long‐term complete response to oral bexarotene. Given its anti‐carcinogenic properties and favorable toxicity profile, oral bexarotene represents an appealing treatment option for PT‐CTCL refractory to skin‐directed therapies.     

CD8‐positive peripheral T‐cell lymphoma with aberrant expression of CD20 and concurrent in situ follicular lymphoma

A case of a 78‐year‐old woman with a CD8‐positive peripheral T‐cell lymphoma with aberrant expression of CD20 associated with follicular lymphoma in situ (FLIS) is reported. The neoplasm presented initially as cutaneous macules, papules, plaques and nodules. A skin biopsy was performed and the diagnosis of peripheral T‐cell lymphoma (PTCl) with aberrant expression of CD20 was made. The staging procedures included an excisional inguinal lymph node biopsy that showed findings similar to those of the previous diagnosis. In addition, FLIS was identified. The clinicopathologic features of PTCLs with aberrant CD20 expression involving the skin as well as this uncommon association are reviewed.     

Cutaneous gamma/delta T‐cell lymphoma

Only 40 cases of primary cutaneous gamma/delta T‐cell lymphoma (GD‐TCL) have been described. GD‐TCL was included as a provisional entity in the WHO‐EORTC classification of cutaneous lymphomas in 2005. GD‐TCL often failed to respond to polychemotherapy and radiation therapy and have a poor prognosis with a mean survival of only 15 months. We present a patient treated with surgery, immunomodulatory therapy, and polychemotherapy. He then received hematopoietic stem cell transplantation and has been in complete remission since. Allogeneic stem cell transplantation appears to be a promising therapeutic option for aggressive and generally fatal lymphomas like GD‐TCL.     

Pseudocarcinomatous hyperplasia mimicking squamous cell carcinoma in a case of CD56‐positive cytotoxic T‐cell lymphoma

We present the case of an 84‐year‐old patient with a cutaneous CD56 positive cytotoxic T‐cell lymphoma associated with substantial pseudocarcinomatous hyperplasia mimicking squamous cell carcinoma (SCC). The patient presented with a 7‐month history of several progressive, ulcerated plaques on his right forearm. An initial biopsy showed changes consistent with a diagnosis of SCC for which the patient underwent surgical treatment. Several months later, the patient developed recurrent ulcerated plaques on the right forearm of which several biopsies were performed. The biopsies repeatedly showed marked pseudocarcinomatous hyperplasia resembling SCC. Deeper punch biopsies, however, showed a dense superficial and deep infiltrate of markedly atypical lymphocytes. Immunohistochemical analysis revealed strong positive staining for CD3, CD8, CD56 with negative stains for CD30 and Epstein‐Barr virus‐encoded small non‐polyadenylated RNAs (EBER). Staining for beta F1 and gamma‐delta T‐cell receptor (γδ TCR) were both negative. This constellation was most consistent with a diagnosis of cutaneous peripheral T‐cell lymphoma, unspecified in association with marked pseudocarcinomatous hyperplasia. Our case adds cutaneous peripheral T‐cell lymphoma, unspecified to the list of conditions associated with pseudocarcinomatous hyperplasia (PCH) and illustrates once again the potential pitfalls of distinguishing marked pseudocarcinomatous hyperplasia from SCC.     

Cutaneous EBV‐positive γδ T‐cell lymphoma vs. extranodal NK/T‐cell lymphoma: a case report and literature review

Primary cutaneous γδ T‐cell lymphoma and extranodal natural killer (NK)/T‐cell lymphoma (ENKTL), nasal type are two distinct lymphoma entities in the World Health Organization (WHO) classification. We report the case of an aggressive cutaneous lymphoma of γδ T‐cell origin showing overlapping features of both lymphomas. A 78‐year‐old female presented with confluent erythematous plaques with ulcerations over her right thigh. Microscopically, section of the skin showed a diffuse dermal and subcutaneous lymphocytic infiltration with tumor necrosis and angioinvasion. The medium‐ to large‐sized tumor cells expressed CD3, CD8, cytotoxic molecules and T‐cell receptor (TCR)‐γ but not CD4, CD20, CD30, CD56 or βF1. In situ hybridization for Epstein‐Barr virus‐encoded mRNA (EBER) was diffusely positive. Polymerase chain reaction‐based clonality assay showed a clonal TCR‐γ chain gene rearrangement. The features compatible with γδ T‐cell lymphoma include dermal and subcutaneous involvements, cytotoxic phenotype, expression of TCR‐γ, as well as an aggressive course. On the other hand, the diffuse EBER positivity, angioinvasion, tumor necrosis and cytotoxic phenotype may also fit in the diagnosis of an ENKTL of T‐cell lineage. We review the literature on EBER‐positive γδ T‐cell lymphoma and discuss the diagnostic dilemma using the current WHO classification system.     

Distinct age‐matched serum biomarker profiles in patients with cutaneous T‐cell lymphoma

Immunological functions decline with age. Because MS/SzS predominately affects the elderly, it is important to distinguish age‐related from cancer‐specific changes. Also, MF and SzS are malignancies of CD4⁺ T‐lymphocytes, further compromising an immune state of the patients. The objectives of this study were to distinguish disease‐specific immunological deterioration by performing comparative age ‐ matched Luminex multiplex assessment of 34 serum biomarkers between patients with MF/SzS, HIV‐infected individuals and normal controls. Controlling for age, expression level appears to significantly differ between patients with MF/SzS and controls for the following biomarkers: G‐CSF, IL‐5, MIP‐1β, TNF‐α, VEGF, EOTAXIN, IL‐8, IL‐12, IL‐2R, IP10, MCP‐1, MIG, TNFR1 and TNFR2 (P < 0.05), while others showed normal age‐related changes. Interestingly, cluster analysis placed MF/SzS profiles closer to HIV. This further underscores an immunologically compromised state of patients with MF/SzS and suggests its potential self‐perpetuating role in disease progression.     

Hematopoietic stem cell transplantation in advanced cutaneous T‐cell lymphoma

We retrospectively reviewed data pertaining to five patients with cutaneous T‐cell lymphoma (CTCL) who had received hematopoietic stem cell transplantation (HSCT) between 2004 and 2015 at Kurume University Hospital, along with their clinical data until March 2016. For patients with advanced CTCL eligible for HSCT, autologous HSCT was performed when they responded well to chemotherapy, and allogeneic HSCT was selected for patients with advanced mycosis fungoides (MF)/Sézary syndrome (SS) and CTCL other than MF/SS with poor chemosensitivity. Two patients (primary cutaneous anaplastic large cell lymphoma and primary cutaneous CD8⁺ aggressive epidermotropic cytotoxic T‐cell lymphoma) who responded well to chemotherapy received autologous HSCT: one patient was alive in partial remission and the other died due to therapy‐related acute myeloid leukemia without disease relapse. In the remaining three patients with MF or SS, allogeneic HSCT was performed. Although one patient with MF died due to disease progression, the remaining two patients were alive in complete remission. Although there were two deaths in this study, the outcomes were considered satisfactory.     

Erythema multiforme‐like cutaneous lesions in monomorphic epitheliotropic intestinal T‐cell lymphoma: a rare case report

Monomorphic epitheliotropic intestinal T‐cell lymphoma (MEITL), also known as Type II enteropathy‐associated T‐cell lymphoma (EATL), is an aggressive peripheral T‐cell lymphoma. EATL generally presents in adults with gastrointestinal symptoms. Skin involvement is very rare, found only in approximately five percent of patients. The authors report a 67‐year‐old Asian male who presented with chronic diarrhea and developed erythema multiforme‐like cutaneous lesions. A skin biopsy revealed extensive pagetoid spread of atypical lymphocytes in the epidermis. The results of an immunohistochemistry test led to a diagnosis of MEITL. This report points to the need for dermatologists and dermatopathologists to consider a possible diagnosis of MEITL when encountering similar cases.     

Primary cutaneous follicular helper T‐cell lymphoma: diagnostic pitfalls of this new lymphoma subtype

The recently proposed entity of cutaneous follicular helper T (T_FH) cell lymphoma (CT_FHCL) harbors distinct clinical and histopathologic features. Here, diagnostic pitfalls are exemplified in a case report and by review of the literature. A 45‐year‐old patient developed rapidly growing nodules and plaques on upper arms and buttocks, which were initially misdiagnosed as primary cutaneous follicle center B‐cell lymphoma (CFCL). Consequently, systemic therapy with rituximab failed and consecutive skin biopsies revealed CT_FHCL (CD3+CD4+CD10+PD‐1+bcl6+ICOS+CXCL13+). Interestingly, the prima vista PD‐1‐positive and CD10‐positive tumor cells lost PD‐1 expression in follow‐up biopsies while retaining CD10, ICOS and CXCL13 expression. All biopsy specimens displayed an identical clonal T‐cell population. Initially, nodules were controlled by local radiotherapy and oral psoralen combined with ultraviolet A (PUVA) therapy. However, disease recurred and progressed rapidly with disseminated nodules. Treatment with bexarotene, methotrexate and polychemotherapy failed to stop disease progression. Finally, modified total skin electron beam radiation resulted in complete remission. Disease stabilized on maintenance therapy with bexarotene in combination with ultraviolet A (UVA) therapy. The case highlights that because of concomitant B‐cell stimulation, CT_FHCL clinicopathologically is prone to be mistaken for CFCL. Importantly, CT_FHCL might lose PD‐1 while retaining CD10 expression in later stages, which may lead to confusion in distinguishing CT_FHCL from CFCL.     

Angioimmunoblastic T‐cell lymphoma with a clonal plasma cell proliferation that underwent immunoglobulin isotype switch in the skin,coinciding with cutaneous disease progression

Plasma cell proliferations in specific cutaneous lesions of angioimmunoblastic T‐cell lymphoma(AITL) are very uncommon. Here, we report a case of clonal plasma cell proliferation in skin with heavy‐chain‐immunoglobulin‐isotype‐switch after cutaneous disease progression. Histopathologically, initial plaque lesions were suggestive of marginal‐zone B‐cell‐lymphoma. Nevertheless, this 77‐year‐old lady was diagnosed with AITL after the progression of skin lesions from plaques to nodular tumors. A lymph node biopsy confirmed the diagnosis. Both cutaneous specimens showed a polymorphic cellular infiltrate with atypical T‐cell‐lymphocytes arranged in a pseudonodular pattern that expressed CD3, PD1 and BCL6, with patchy expression of CD30. Interestingly, a slight IgG‐Lambda plasma cell component was seen at the periphery of the infiltrate in the first specimen which increased in number in the later nodular lesion, showing not only Lambda light chain restriction and IgG but also IgG4. PCR studies for IgH and TCR genes showed an IgH clonal peak on both skin lesions but not on lymph node biopsy. On the contrary, the same clonal TCR peak was found in the three specimens. Neoplastic follicular helper T‐cells within cutaneous‐specific microenvironment could be responsible for the modulation of the immunoglobulin isotype class switch change. Further studies are needed to support this hypothesis.