Past, present and future of cutaneous lymphomas

Mycosis fungoides and Sézary syndrome: clinical presentation, diagnosis, staging, and therapeutic management

Mycosis fungoides (MF) and Sézary syndrome (SS) are cutaneous T-cell lymphomas. MF is the most common cutaneous lymphoma, and it is classified into classic Alibert-Bazin MF, folliculotropic MF, pagetoid reticulosis, and granulomatous slack skin, each with characteristic clinical presentation, histopathological findings, and distinct clinical behaviors. SS is an aggressive leukemic variant of cutaneous lymphoma, and it is characterized by erythroderma, lymphadenopathy, and peripheral blood involvement by malignant cells. There is a wide range of dermatological manifestations of MF/SS, and prompt recognition is essential for early diagnosis. Skin biopsy for histopathology and immunohistochemical analysis is imperative to confirm the diagnosis of MF/SS. Histopathology may also provide information that may influence prognosis and treatment. Staging follows the TNMB system. Besides advanced stage, other factors associated with poorer prognosis are advanced age, male gender, folliculotropism in histopathology of patients with infiltrated plaques and tumors in the head and neck region, large cell transformation, and elevated lactate dehydrogenase. Treatment is divided into skin-directed therapies (topical treatments, phototherapy, radiotherapy), and systemic therapies (biological response modifiers, targeted therapies, chemotherapy). Allogeneic bone marrow transplantation and extracorporeal photopheresis are other treatment modalities used in selected cases. This review discusses the main clinical characteristics, the histopathological/immunohistochemical findings, the staging system, and the therapeutic management of MF/SS.

Primary Cutaneous Diffuse Large B-Cell Lymphoma, Leg Type: A Case Report

Primary cutaneous diffuse large B-cell lymphoma, leg type, is an exceedingly rare and aggressive variant of primary cutaneous lymphoma. An 84-year-old male presented to an oncologist for new skin lesions on his abdomen and right thigh. Excisional biopsy followed by histopathology and immunohistochemistry confirmed the diagnosis of primary cutaneous diffuse large B-cell lymphoma, leg type. His clinical course was complicated by multiple relapses and refractory disease. Ultimately, he achieved complete response with fourth-line ibrutinib therapy. Due to the contentious nature of this disease, poor prognosis, and higher rates of recurrence, prompt identification and aggressive treatment are recommended. Given the different cellular pathways and genomic alterations identified in its carcinogenesis, various chemotherapy regimens and targeted immunotherapies have emerged as potential therapeutic options to halt disease progression and prevent future relapses.

A Systematic Approach to the Cutaneous Lymphoid Infiltrates: A Clinical, Morphologic, and Immunophenotypic Evaluation

CONTEXT.—

The evaluation of cutaneous lymphoid infiltrates, both neoplastic and inflammatory, occurs very frequently in routine dermatopathologic examination and consultation practices. The "tough" cutaneous lymphoid infiltrate is feared by many pathologists; skin biopsies are relatively small, whereas diagnostic possibilities are relatively broad. It is true that cutaneous lymphomas can be difficult to diagnose and that in many circumstances multiple biopsies are required to establish a correct diagnostic interpretation. As a reminder, one should understand that low-grade cutaneous lymphomas are indolent disorders that usually linger for decades and that therapy does not result in disease cure. It is also important to remember that in most circumstances, those patients will die from another process that is completely unrelated to a diagnosis of skin lymphoma (even in the absence of specific therapy).

OBJECTIVE.—

To use a clinicopathologic, immunophenotypic, and molecular approach in the evaluation of common lymphocytic infiltrates.

DATA SOURCES.—

An in-depth analysis of updated literature in the field of cutaneous lymphomas was done, with particular emphasis on updated terminology from the most recent World Health Organization classification of skin and hematologic tumors.

CONCLUSIONS.—

A diagnosis of cutaneous lymphoid infiltrates can be adequately approached using a systematic scheme following the proposed ABCDE system. Overall, cutaneous T- and B-cell lymphomas are rare and "reactive" infiltrates are more common. Evaluation of lymphoid proliferations should start with a good sense of knowledge of the clinical presentation of the lesions, the clinical differential considerations, and a conscientious and appropriate use of immunohistochemistry and molecular tools.

Diagnosis of T-cell lymphoid proliferations of the skin: putting all the pieces together

The spectrum of T-cell lymphoid proliferations of the skin varies from indolent to highly aggressive diseases and therefore an accurate pathological diagnosis is paramount. Integration of clinical, histopathological, immunohistochemical, and molecular findings is of crucial importance in the evaluation of these processes. In this article, we discuss selected situations where difficulty may arise for the pathologist evaluating this type of skin biopsies, such as: the diagnosis of early (patch stage) mycosis fungoides, the distinction of mycosis fungoides with large cell transformation from primary cutaneous anaplastic large cell lymphoma, the recognition of new histopathological patterns of lymphomatoid papulosis and the entities they mimic, the evaluation of primary cutaneous anaplastic large cell lymphoma with expression of markers suggestive of systemic origin (such as ALK), the awareness of the wide range of clinical and pathological presentations of hydroa vacciniforme-like EBV-positive T-cell lymphoproliferative disorders, the evaluation of cases of primary cutaneous γδ T-cell lymphoma showing predominantly epidermotropic pattern of growth, and the correct interpretation of findings seen in indolent proliferations such as primary cutaneous acral CD8-positive T-cell lymphoma and primary cutaneous small/medium size CD4 + T-cell lymphoproliferative disorder.

Interferon alfa-2a maintenance after salvage autologous stem cell transplantation in atypical mycosis fungoides with central nervous system involvement

Mycosis fungoides (MF) is a primary cutaneous T-cell lymphoma with unfavourable prognosis for patients with advanced stages of the disease. Refractory disease and advanced-stage disease require systemic therapy. We report on a rare case of an atypical predominantly CD8⁺ folliculotropic MF, a subtype of MF with poorer prognosis, in a 59-year-old woman. She was initially diagnosed with MF restricted to the skin, of T3N0M0B0/stage IIB according to the current World Health Organization-European Organisation for Research and Treatment of Cancer classification. First-line treatment with local percutaneous radiotherapy in combination with systemic interferon alfa-2a resulted in complete remission. However, 21 months later the disease progressed to T3N0M1B0/stage IVB with development of cerebral manifestation and thus very poor prognosis. Allogeneic stem cell transplantation (SCT) was not a therapeutic option due to the lack of a suitable donor. We initiated methotrexate and cytarabine chemotherapy, followed by high-dose chemotherapy with thiotepa and carmustine with autologous SCT. Despite rapid response and complete remission of the cerebral lesions, disease recurrence of the skin occurred soon after. Interestingly, readministration of interferon alfa-2a as a maintenance treatment after the salvage autologous SCT resulted in a durable complete remission during the follow-up period of currently 17 months after autologous SCT. What's already known about this topic? Mycosis fungoides is a primary cutaneous T-cell lymphoma with unfavourable prognosis for the advanced stages of the disease. A refractory course of disease requires systemic therapy. What does this study add? We report on an unusual case of a patient with mycosis fungoides with cerebral involvement, in which a durable complete remission was achieved upon autologous stem cell therapy and interferon alfa-2a maintenance therapy.

Cutaneous Lymphoproliferative Disorders: What's New in the Revised 4th Edition of the World Health Organization (WHO) Classification of Lymphoid Neoplasms

Cutaneous lymphoproliferative disorders remain a challenging aspect of dermatopathology, in part due to the rarity of the entities and extreme variability in clinical outcomes. Although many of the entities remain unchanged, the approach to some of them has changed in the new 2016 classification scheme of the World Health Organization. Chief among these are Epstein-Barr virus-associated lymphoproliferative disorders such as Epstein-Barr virus-associated mucocutaneous ulcer and hydroa vacciniforme-like lymphoproliferative disorder, primary cutaneous CD8+ aggressive epidermotropic cytotoxic T-cell lymphoma, primary cutaneous acral CD8+ T-cell lymphoma, primary cutaneous CD4+ small/medium T-cell lymphoproliferative disorder, and breast implant-associated anaplastic large cell lymphoma. In addition, translocations and gene rearrangements such as those involving the 6p25.3 locus have started to inform diagnosis and classification of anaplastic large cell lymphoma and lymphomatoid papulosis. In this review, we will examine what is new in the diagnostic toolbox of cutaneous lymphoproliferative disorders.

Photo-photochemotherapy in Juvenile-onset Mycosis Fungoides: A Retrospective Study on 9 Patients

Mycosis fungoides (MF) is a rare disease and is considered the most common form of cutaneous T-cell lymphoma. Given the infrequent incidence of MF in patients under the age of 20, there are no established guidelines for the treatment of these patients; the overwhelming majority have an early-stage disease and progression to more advanced stages is very rare. This study presents the safety and effectiveness of photo-photochemotherapy as a first-line approach in the treatment of an early-stage MF even in young patients.

Synchronous Occurrence of Mycosis Fungoides, Diffuse Large B Cell Lymphoma and Acute Myeloid Leukemia

Patients with mycosis fungoides (MF), the most common subtype of primary cutaneous T-cell lymphoma, have an increased risk of developing secondary malignancies. We herein report two rare cases of MF concurring with diffuse large B cell lymphoma (B lymphoid lineage) and acute myeloid leukemia (myeloid lineage) in two otherwise healthy elderly patients. Potential etiologic factors, including the impact of the therapy-associated inflammatory response on the development of secondary tumors in patients with MF, are discussed. Further clinical, experimental and genetic studies are needed to elucidate possible physiopathogenic associations among the three concurrent malignancies occurring in the cases presented here.