Cutaneous Lymphomas

Total skin electron beam therapy

Primary cutaneous lymphomas are highly radiosensitive. X-rays work well for localized cutaneous lymphomas. However, if disseminated in the skin and covering larger areas, as is commonly the case with the most common type, mycosis fungoides, x-ray therapy is not suited because the dose to underlying organs exceeds their tolerance. By contrast, electrons have a limited range of penetration, and are ideal for treating superficial lesions. Techniques have been developed to yield a fairly uniform dose to the entire skin surface and treating to a depth of about 1-1½ cm. Total skin electron beam therapy (TSEBT) is probably the most effective skin directed therapy for widespread primary cutaneous lymphomas. For many years the total dose used for mycosis fungoides was 30-36 Gy, given in small fractions. This treatment could only be repeated once. However, total doses of 10-12 Gy have now been shown to offer excellent response rates, and the treatment can be repeated up to 6 times, offering as much or probably even more palliation than the high-dose treatment. Today, most patients are treated with low-dose TSEBT, the higher doses reserved for patients with more resistant disease. Attempts have been made to use photon therapy for total skin irradiation, e.g., tomotherapy. However, even with the most meticulous of techniques there is too much dose in deeper structures, resulting in bone marrow toxicity even with low-dose treatment. This is never seen with electrons, even with high-dose therapy. Further research into optimizing TSEBT and exploring combinations with systemic treatments is ongoing.

Breaking Down the Barriers for Patients With Cutaneous T-Cell Lymphoma: Current Controversies and Challenges for Radiation Oncologists in 2024

Cutaneous T-cell lymphomas (CTCL) are a rare collection of diseases, frequently associated with diagnostic challenges and complex management dilemmas. The multidisciplinary team is vital for accurate clinico-pathological diagnoses and for collaborative therapeutic decisions throughout the management journey, which frequently involves multiple lines of therapy. Radiotherapy (RT) is a highly effective skin-directed therapy for CTCL, commonly delivered as localised fields or as total skin electron beam therapy (TSEBT). Mycosis fungoides (MF) is the most common of the CTCL, and patients typically experience high rates of morbidity and long natural histories of relapse and progression. Patients with MF typically present with incurable disease; in these patients, RT has an established role in symptom- and disease-control, achieving excellent response rates and proven therapeutic benefits. The role of RT continues to evolve, with modern practices favouring lower doses to reduce toxicity risks and allow for re-irradiation. Less commonly, there are situations where RT has an integral role in the potential cure of patients with MF: firstly, in the setting of unilesional MF where localised RT alone may be curative, and secondly, in the setting of preconditioning prior to curative-intent allogeneic hematopoietic stem cell transplant for patients with advanced MF/Sezary syndrome, where conventional-dose TSEBT is indicated as the most effective single agent for maximal debulking of skin disease. Radiotherapy also has an important role in the management of the less common CTCL, including the curative treatment of localised primary cutaneous anaplastic large cell lymphoma. Despite proven efficacy and quality of life benefits, disparity exists in access to RT and TSEBT. World-wide, stronger multidisciplinary collaborations and greater patient advocacy are required to increase access to RT and improve equity of care for our patients with CTCL.

Characteristics of Primary Cutaneous Lymphoma in Italy: A Tertiary Care, Single-Center Study

Data on primary cutaneous lymphomas (PCLs) patients in the Italian population are limited, and, despite the existence of several treatment options, the management of those patients remains challenging. Our study aimed to investigate the clinical and therapeutic features of PCL patients in a referral center in Italy. We conducted a retrospective study on 100 consecutive PCL patients between January 2017 and December 2022. The mean (SD) age of our cohort was 70.33 (14.14) years. Cutaneous T-cell lymphomas (CTCLs) represented 65% of all cases; the majority were mycosis fungoides (42%), followed by cases of Sezary syndrome (10%) and primary cutaneous anaplastic large cell lymphoma (4%). Cutaneous B-cell lymphomas (CBCLs) accounted for 35 % of PCLs, with 15 cases of primary cutaneous follicle center lymphoma, 10 cases of primary cutaneous diffuse large B-cell lymphoma leg type, and 9 cases of marginal zone B-cell lymphoma. A higher frequency of pruritus (p = 0.008) and higher peripheral blood levels of beta-2 microglobulin (p ≤ 0.001) and lactate dehydrogenase (p = 0.025) were found in CTCLs compared to those of CBCLs. Considering all therapeutic lines performed, treatments were extremely heterogeneous and skin-directed therapies represented the most frequently used approach. Our study confirms the distribution of PCL subtypes formerly reported in the literature and highlights the utility of real-life data in treatments to improve the current management of PCL patients.

Cutaneous epitheliotropic T-cell lymphoma in a donkey - a case report

Background

Cutaneous epitheliotropic T-cell lymphoma is a malignant tumour of the skin already reported in humans, dogs, cats, horses, and other species, but not previously in donkeys. The standard diagnosis is based on clinical, morphological and immunophenotypic data. Differentiation of malignant versus benign proliferation of lymphocytes is crucial; in ambiguous cases T-cell receptor gamma (TRG) molecular clonality should be tested. In the present paper, we report a case of mycosis fungoides diagnosed in a donkey whose diagnosis was based on clinical, histological and immunohistochemical aspects and a positive TRG clonality test.

Case presentation

A twenty-five-year-old donkey gelding was referred with a mildly pruritic, generalised and severe exfoliative dermatosis. Otherwise, the animal was clinically healthy, though mildly underweight. Dermatological examination revealed severe generalised alopecic and exfoliative dermatitis, occasionally eroded, with high number of large, thin, greyish scales. All mucocutaneous junctions except the hoofs were affected. Ectoparasites and dermatophytes were ruled out. The complete blood count and blood smear evaluation revealed mild normocytic normochromic anemia. The biochemistry panel showed mild hyperproteinemia with albumin within the normal range. Protein electrophoresis showed moderate polyclonal hypergammaglobulinemia. Histological findings were characterised by interface dermatitis with massive exocytosis in the epidermis of a homogenous population of lymphoid cells showing atypia. Clusters of neoplastic cells were present within the epidermis forming Pautrier “microabscesses”. These findings are consistent with cutaneous epitheliotropic lymphoma. Immunohistochemical staining revealed uniform labelling of the neoplastic cells for CD3, and lack of expression of CD20 (a B cell lineage associated marker). Molecular clonality PCR (PARR) was performed using equine TRG primers; this revealed a clonal rearrangement in a heavy polyclonal background. Transmission electronic microscopy showed multiple lymphocytes with convoluted or cerebriform nuclei.

Conclusions

This case report provides the first evidence of clinical, histopathological, immunophenotypic features, electron microscopy findings and molecular analysis of a cutaneous epitheliotropic T-cell lymphoma (mycosis fungoides) in a donkey. Our observations suggest that cutaneous T-cell lymphoma should be included in the differential diagnoses of exfoliative dermatitis, even those progressing in a chronic pattern and/or with few or no pruritus.

A Comprehensive Update of the Atypical, Rare and Mimicking Presentations of Mycosis Fungoides

Introduction

Mycosis fungoides (MF) is the most frequent subtype of primary cutaneous T cell lymphomas (pCTCL). The diagnosis may be particularly difficult in the early stages as well as in atypical and rare clinical presentations. Furthermore, MF may simulate a large variety of common dermatologic disorders and patterns, both histopathologically and clinically.

Methods

A literature search was performed to provide a comprehensive update on the rare and atypical MF manifestations as well as the dermatoses and dermatological patterns that could be imitated by MF.

Results

A total of 114 publications were found describing a series of different dermatoses and dermatological patterns mimicked by MF, as well as some particular localizations of MF lesions and dermatoses that occur in preexisting MF lesions.

Conclusions

The number of dermatoses that can be imitated by MF is ever-increasing. Patients with common dermatologic conditions that prove to be treatment refractory should be biopsied without delay, and sequentially as necessary, to prevent delay in diagnosis and progression of disease. Clinicopathologic correlation is the best way of diagnosis.