Rare Cutaneous T-Cell Lymphomas

No Longer Cutaneous T-cell Lymphoma Dermal Nodule

Primary cutaneous CD4+ small and medium pleomorphic T-cell lymphoproliferative disorder (PCSM-LPD) is a rare and typically asymptomatic proliferation of CD3+/CD4+ small and medium pleomorphic T-cells. In this case report, we share the details of a 41-year-old male presenting with a two-centimeter soft, mobile forehead nodule that was determined by clinical symptoms, histology, and immunostaining to be PCSM-LPD. We would like to emphasize the clinical resolution that was seen with minimal treatment.

Cutaneous Deep Ulcerations as Initial Presentations of Granulomatosis with Polyangiitis: Two Case Reports and Differential Diagnosis

Background: Granulomatosis with polyangiitis (GPA) is an antineutrophil-cytoplasmic-antibody (ANCA)-associated small-vessel vasculitis characterized by necrotizing granulomatous inflammation. Symptoms of skin involvement can appear in 30–50% of patients with GPA, and may present as the initial presentation. Case Presentation: We describe two patients who presented with multiple deep, large, nonhealing skin ulcers postoperatively with purulent drainage and fever. Both patients were diagnosed with GPA after an extensive evaluation, including histopathology. Infectious, connective tissue disease and malignant etiologies were excluded. Their cANCA and PR3-ANCA levels were positive. Patient 2 was diagnosed early and recovered well after treatment with corticosteroids and rituximab; however, Patient 1 had a poor prognosis due to a long disease course. Conclusions: Diseases with multiple deep, large skin ulcers and fever can be infectious or noninfectious. Atypical manifestations may lead to missed diagnosis and misdiagnosis. GPA may initially present in a localized form before progressing to a generalized disease. The two cases we have highlighted will prompt clinicians to nevertheless call for a low threshold for diagnosis.

Molecular pathogenesis of Cutaneous T cell Lymphoma: Role of chemokines, cytokines, and dysregulated signaling pathways

Cutaneous T cell lymphomas (CTCLs) are a heterogeneous group of lymphoproliferative neoplasms that exhibit a wide spectrum of immune-phenotypical, clinical, and histopathological features. The biology of CTCL is complex and remains elusive. In recent years, the application of next-generation sequencing (NGS) has evolved our understanding of the pathogenetic mechanisms, including genetic aberrations and epigenetic abnormalities that shape the mutational landscape of CTCL and represent one of the important pro-tumorigenic principles in CTCL initiation and progression. Still, identification of the major pathophysiological pathways including genetic and epigenetic components that mediate malignant clonal T cell expansion has not been achieved. This is of prime importance given the role of malignant T cell clones in fostering T helper 2 (Th2)-bias tumor microenvironment and fueling progressive immune dysregulation and tumor cell growth in CTCL patients, manifested by the secretion of Th2-associated cytokines and chemokines. Alterations in malignant cytokine and chemokine expression patterns orchestrate the inflammatory milieu and influence the migration dynamics of malignant clonal T cells. Here, we highlight recent insights about the molecular mechanisms of CTCL pathogenesis, emphasizing the role of cytokines, chemokines, and associated downstream signaling networks in driving immune defects, malignant transformation, and disease progression. In-depth characterization of the CTCL immunophenotype and tumoral microenvironment offers a facile opportunity to expand the therapeutic armamentarium of CTCL, an intractable malignant skin disease with poor prognosis and in dire need of curative treatment approaches.

Gamma/Delta Phenotype in Primary Cutaneous T-cell Lymphomas and Lymphoid Proliferations: Challenges for Diagnosis and Classification

Primary cutaneous T-cell lymphomas pose a diagnostic challenge for dermatopathologists, hematopathologists, and general surgical pathologists. Recognition of gamma/delta phenotype in cutaneous T proliferations has been enhanced by the availability of antibodies against TCRgamma and delta for immunohistochemistry. Thus, reporting gamma/delta phenotype in a cutaneous T-cell lymphoid proliferation may indicate a significant change in therapy and a challenge for dermatologists and oncologists who treat these patients. Herein, we discuss primary cutaneous gamma/delta T-cell lymphoma, its differential diagnosis, and other skin lymphoid proliferations that may show gamma/delta phenotype. Awareness of the occurrence of gamma/delta phenotype in both T-cell lymphomas and benign lymphoid proliferations involving skin is crucial for a better interpretation of histopathologic findings. Integration of clinical presentation, morphology, immunoprofile, and molecular findings is key for a correct diagnosis and appropriate therapy of lesions displaying gamma/delta T-cell phenotype.

The Clinical Spectrum of Primary Cutaneous CD4+ Small/Medium-Sized Pleomorphic T-Cell Lymphoproliferative Disorder: An Updated Systematic Literature Review and Case Series

BACKGROUND

Primary cutaneous CD4+ small/medium pleomorphic T-cell lymphoproliferative disorder (SMPLPD) is a provisional entity within the 2016 World Health Organization classification of primary cutaneous lymphomas. The condition is currently classified as a lymphoproliferative disorder to emphasize its benign course and discourage aggressive, systemic treatment modalities.

OBJECTIVE

To provide a relevant synthesis for the dermatological practitioner on the prevalence, presentation, and treatment of SMPLPD.

METHODS

We conducted an updated systematic literature review and a retrospective chart review of diagnosed cases of SMPLPD from 2 Canadian academic cutaneous lymphoma centers.

RESULTS

A total of 23 studies with 136 cases were extracted from the systematic review and 24 patients from our retrospective chart review. SMPLPD proved relatively common accounting for 12.5% of all cutaneous T-cell lymphomas encountered in our cutaneous lymphoma clinics, second in frequency only to mycosis fungoides. The typical clinical presentation was that of an older individual (median age 59 years) with an asymptomatic solitary lesion on their upper extremity. The most common clinical differentials were cutaneous lymphoid hyperplasia, basal cell carcinoma, and lymphoma unspecified. T follicular helper markers were reliably detected. The main treatment modalities were surgical excision, local radiation therapy, and topical or intralesional steroids. Cure was achieved in the vast majority of cases.

CONCLUSIONS

SMPLPD is an underdiagnosed T-cell lymphoma with an overtly benign clinical course. The condition has an excellent prognosis and responds well to skin-directed therapies. Practitioners should be aware of this condition to avoid aggressive systemic treatments.

Monomorphic Epitheliotropic Intestinal T-Cell Lymphoma With Secondary Cutaneous Involvement: A Diagnostic Challenge

ABSTRACT

A 45-year-old woman presented with a solitary breast nodule that histologically corresponded to a dense dermal/subcutaneous infiltration of atypical cytotoxic T-lymphocytes (CD3+, CD8+, CD56+, TIA-1+, CD5-, CD4-, CD30-, EBV-), resembling subcutaneous panniculitic T-cell lymphoma. The presence of TCRδ gene rearrangement and the absence of βF1 expression let to suspect the diagnosis of primary cutaneous γδT-cell lymphoma. As a consequence of jejunum perforation following chemotherapy treatment, a mucosal atypical lymphoid infiltration with marked epitheliotropism was observed in the resected intestinal sample, and the diagnosis of monomorphic epitheliotropic intestinal T-cell lymphoma (MEITL) was finally established. Disease progression appeared with multiple erythematous plaques showing a dense lichenoid atypical cytotoxic T-cell infiltrate with intense epidermotropism, mimicking primary cutaneous epidermotropic aggressive CD8+ T-cell lymphoma. MEITL is an uncommon and aggressive peripheral T-cell lymphoma that often presents in adults with gastrointestinal symptoms. Secondary cutaneous involvement is a rare phenomenon that may show clinicopathologic and immunohistochemical features that overlap with different subtypes of primary cutaneous cytotoxic T-cell lymphomas. In the absence of gastrointestinal symptoms, the diagnosis may be challenging, and only the evidence of underlying MEITL may allow to establish the definite diagnosis.

Nasal-type extranodal natural killer/T-cell lymphoma presenting with a mass on the buttock: A case report

RATIONALE

Nasal-type extranodal natural killer (NK)/T-cell lymphoma is a highly unusual disease with no standard curative managements yet. Our focus is to emphasize a very rare case of nasal-type extranodal NK/T-cell lymphoma with onset of the mass on the buttock successfully operated by combination of surgical excision together with chemotherapy. The management of these unique cases is of great clinical guiding significance.

PATIENT CONCERNS

A 20-year-old woman presented with a 2-month history of continuous and progressive severe pain on her left buttock. Since December 2017, the patient developed nasal congestion, accompanied with mild pain in the left eye, and new subcutaneous nodules on both cheeks.

DIAGNOSIS

Postoperative pathology confirmed the diagnosis of extranodal NK/T cell lymphoma. This is an extremely rare presentation of nasal-type NK/T-cell lymphoma.

INTERVENTIONS

The patient underwent enlarged resection of the tumor on the buttock. After the diagnosis of extranodal NK/T-cell lymphoma was established, the patient received chemotherapy and autologous hematopoietic stem cell transplantation.

OUTCOMES

The patient's symptoms improved significantly after the surgery, and the postoperative period was uneventful at the 1-year follow-up visit. There were no complications associated with the operation and adjuvant therapies during the follow-up period.

LESSONS

Taken together, the lesion's clinical features, imaging results, and pathological characteristics are unique. Extranodal NK/T-cell lymphoma, although rare, should be part of the differential diagnosis when the patient presents with the mass on the buttock. We recommend enlarged excision of the extranodal lymphoma. Combined of surgical excision of the extranodal lymphoma, chemotherapy and autologous hematopoietic stem cell transplantation are good choice for proper treatment.

Primary cutaneous CD4-positive small/medium T-cell lymphoproliferative disorder: The first-reported Latin-American case with response to doxycycline

Primary cutaneous CD4+ small/medium T-cell lymphoproliferative disorder is a provisional entity according to the last WHO-EORTC classification. The treatment of choice has not yet been defined. Local therapies have been used with variable response. Doxycycline as a main treatment option is a potential low-cost and effective alternative for this disorder.

Recent Advances in Cutaneous T-cell Lymphoma: Diagnostic and Prognostic Considerations

This review describes the latest advances in the diagnosis of cutaneous T-cell lymphoma focusing on the most clinically useful features introduced since the publication of the World Health Organization revision in 2017. Clinical entities described include mycosis fungoides, Sézary syndrome, lymphomatoid papulosis, primary cutaneous anaplastic large cell lymphoma, primary cutaneous gamma delta T-cell lymphoma, primary cutaneous acral CD8⁺ T-cell lymphoma, primary cutaneous CD4⁺ small/medium T-cell lymphoproliferative disorder, and hydroa-vacciniforme-like lymphoproliferative disorder. Distinguishing histologic clues to diagnosis are discussed, and important molecular advances are described. Key prognostic indicators that may assist clinicians with timely and appropriate management options are presented.