Spatial transcriptomics reveals heterogeneity of macrophages in the tumor microenvironment of granulomatous slack skin

Granulomatous slack skin (GSS) is an extremely rare subtype of cutaneous T-cell lymphoma accompanied by an abundant number of macrophages and is clinically characterized by the development of pendulous skin folds. However, the characteristics of these macrophages in GSS remain unclear. Here, we conducted a spatial transcriptomic study on one frozen GSS sample and drew transcriptomic maps of GSS for the first time. Gene expression analysis revealed the enrichment of three clusters with macrophage transcripts, each exhibiting distinct characteristics suggesting that their primary composition consists of different subpopulations of macrophages. The CD163+ /CD206+ cluster showed a tumor-associated macrophage (TAM) M2-like phenotype and highly expressed ZFP36, CCL2, TNFAIP6, and KLF2, which are known to be involved in T-cell interaction and tumor progression. The APOC1+ /APOE+ cluster presented a non-M1 or -M2 phenotype and may be related to lipid metabolism. The CD11c+ /LYZ+ cluster exhibited an M1-like phenotype. Notably, these cells strongly expressed MMP9, MMP12, CHI3L1, CHIT1, COL1A1, TIMP1, and SPP1, which are responsible for extracellular matrix (ECM) degradation and tissue remodeling. This may partially explain the symptoms of cutaneous relaxation in GSS. Further immunohistochemistry on four GSS cases demonstrated that CD11c predominantly marked granulomas and multinucleated giant cells, whereas CD163 was mainly expressed on scattered macrophages, appearing as a mutually exclusive pattern. The expression pattern of MMP9 overlapped with that of CD11c, implying that CD11c+ macrophages may be a source of MMP9. Our data shed light on the characteristics of macrophages in the GSS microenvironment and provide a theoretical basis for the application of MMP9 inhibitors to prevent cutaneous relaxation of GSS. © 2023 The Authors. The Journal of Pathology published by John Wiley & Sons Ltd on behalf of The Pathological Society of Great Britain and Ireland.

Cutaneous T-cell lymphoma with CNS involvement: a case series and review of the literature

Cutaneous T-cell lymphoma (CTCL) is a rare hematologic malignancy that traditionally presents with cutaneous lesions, though metastases are not uncommon in progressive disease. We describe four cases of CTCL with central nervous system (CNS) involvement, detailing the history, pathological characteristics, treatment response, and progression. Median time from initial diagnosis to CNS metastasis was ∼5.4 years (range 3.4-15.5 years) and survival after metastasis was ∼160 days (range 19 days-4.4 years). No patients achieved long-term (>5 years) survival, though some displayed varying degrees of remission following CNS-directed therapy. We conclude that clinicians must be attentive to the development of CNS metastases in patients with CTCL. The growing body of literature on such cases will inform evolving therapeutic guidelines on this rare CTCL complication.

Clinical analysis of 20 cases of cutaneous extranodal NK/T-Cell lymphoma

Background To investigate the clinical features, pathological features and prognostic factors of cutaneous extranodal natural killer/T-cell lymphoma (CENKTL). Methods A total of 20 cases with CENKTL from February 2013 to November 2021 were analysed retrospectively. Results The patients included 15 men and five women, and their ages ranged from 19 to 92 (median age of 61) years. The most common lesions were on the extremities, followed by the trunk. Histopathological examination showed atypical lymphocyte infiltrate in dermis and subcutaneous fat. The tumour tissue showed vascular proliferation, vascular occlusion, and coagulation necrosis. In situ hybridisation revealed that 20 patients were positive for Epstein-Barr virus-coding ribonucleic acid. Immunohistochemistry showed that the tumour cells were positive for CD3 (18/20 and 90%), CD56 (19/20 and 95%), T-cell intracellular antigen (TIA-1) (13/14 and 92.9%) and CD20 (5/20, 25%). About 20 patients were positive for Ki-67 with values of 30-90%. A total of 11 of the 20 patients died, and two patients were lost to follow-up. The 2-year overall survival was 24%, and the median overall survival was 17 months. Univariate analysis revealed that involvement of lymph nodes (P = 0.042) correlated with worse survival. Limitation This is a retrospective study design and has a limited number of patients. Conclusion CENKTL is rare and has a poor prognosis. Diagnosis is challenging due to non-specific clinical symptoms and histopathology results. A comprehensive judgement should be made based on related clinical manifestations and histopathological and molecular examination. Lymph node involvement is an independent prognostic factor for CENKTL.

Clonal disease in early cutaneous T-cell lymphoma

Our experience with 185 cases of T-cell dominated skin infiltrates demonstrates that the PCR-based method for detection of TCR gamma chain gene rearrangement in combination with temperature gradient electrophoresis can routinely be used for the demonstration of clonal T cells in formalin-fixed and paraffin-embedded biopsies of lesional skin. In contrast to Southern blot analysis, the amplification by PCR is nonradioactive, is not time consuming (approximately 3 days), can be performed using frozen or paraffin-embedded tissue, and allows additional molecular biologic analyses, such as sequencing. Furthermore, it offers the possibility to design patient-specific primers for monitoring of the disease activity. It also has to be concluded from our study that all available clinical, histologic, cytologic, immunophenotypical, and rearrangement studies have to be considered in order to establish the correct diagnosis.

Genotypic analysis of cutaneous T-cell lymphoma: a comparative study of Southern blot analysis with polymerase chain reaction amplification of the T-cell receptor-gamma gene

The diagnosis of early cutaneous T-cell lymphoma (CTCL) is a difficult point in dermatology. Recently, Southern blot analysis (SBA) and polymerase chain reaction (PCR) have been used to detect clonality in initial lesions in which clinical and histological findings are unspecific. Forty-one samples from 25 patients with CTCL were investigated for the presence of T-cell receptor-gamma gene rearrangement using a nested PCR technique and analysed by polyacrylamide gel electrophoresis (PAGE). Conventional SBA was also performed on 28 samples from 20 of these patients. In addition, 20 samples corresponding to patients with large plaque parapsoriasis (LPP), cutaneous B-cell lymphoma (CBCL) and eczema were analysed by PCR in the same way as were the CTCL specimens. Most of the CTCL specimens (81%) showed clonality on PCR analysis. Among patients with mycosis fungoides, 71% of initial patch lesions and 100% of plaques and tumours showed clonal disease. Clonality could be detected in three of four histologically negative post-treatment lesions. Clonal rearrangement was detected in one of three patients with LPP and in three of 10 patients with CBCL. None of the samples corresponding to patients with eczema showed positive results. SBA was significantly less sensitive than PCR in detecting clonality in CTCL patients (42% among early disease and 60% among advanced cases). The results indicate that this PCR/PAGE technique is a reliable and useful method for the detection of clonality in early skin lesions of CTCL patients and probably in the identification of silent extracutaneous involvement.

Heteroduplex analysis of T-cell receptor gamma gene rearrangements for diagnosis and monitoring of cutaneous T-cell lymphomas

The possibility to detect markers of T-cell clonality at the T-cell receptor (TCR) beta and gamma loci in skin biopsy samples has proven to be helpful for the often difficult clinical and immunohistochemical diagnosis of cutaneous T-cell lymphoma (CTCL). However, particularly at the early stage of the neoplastic infiltration, an emerging clonal pattern at Southern may be obscured by the germline TCR configuration of the predominant dermal and epidermal cell component. Additionally, multiple TCR gamma rearranged bands of variable intensity are often observed, either in the presence or in the absence of a major clone. To overcome these difficulties, we have investigated the T-lymphocyte clonality in selected patients with variable signs of CTCL by means of heteroduplex analysis of the amplified TCR gamma VJ junctions, separated in nondenaturing polyacrylamide gel. This technique has several advantages over standard Southern blot because it is simple, rapid, not radioactive, and likely more sensitive than other polymerase chain reaction-based procedures. In particular, the cases with uncertain or contradictory TCR beta and gamma patterns were solved by the heteroduplex analysis, showing homoduplex or heteroduplex bands of clonal nature. The direct sequence of the VJ junctions, easily obtained from the homoduplex or heteroduplex bands, allowed us to confirm the same clonal marker in two apparently different skin lesions and in different biopsy samples obtained from the same patients, either at the same or different time points, thus emphasizing the utility of this method in monitoring CTCL clinical progression.

Epidemiology and clinical manifestations of cutaneous T-cell lymphoma

Cutaneous T-cell lymphoma (CTCL) encompasses a constellation of diseases of malignant clonal T lymphocytes that present initially in the skin. Within this disease spectrum, mycosis fungoides, and the Sézary syndrome are best known. Progress in the understanding of the T-cell malignancies now places other clinical entities within this disease classification. The authors review the epidemiology and clinical manifestations of CTCL.

Primary cutaneous gamma-delta T-cell lymphoma masquerading as leukemia cutis in a patient recently diagnosed with small lymphocytic lymphoma: Clues to the diagnosis

A 54-year-old man recently diagnosed with small lymphocytic lymphoma (SLL) had waxing and waning, indurated, erythematous plaques on his legs, with leukopenia and anemia disproportionate to the SLL burden in his marrow and pelvic lymph nodes. Punch biopsy of a plaque performed to evaluate for leukemia cutis revealed a lymphocytic lobular-panniculitis-like infiltrate resembling lupus panniculitis, but a preponderance of CD8+/Ki-67+ T-cells surrounding adipocytes raised concern for subcutaneous panniculitis-like T-cell lymphoma (SPTCL). Additional immunohistochemistry (IHC) studies showed that the adipotropic T-cells expressed TCR-gamma, supporting the rare, unexpected diagnosis of Primary cutaneous gamma-delta T-cell lymphoma (PCGDTCL). The patient subsequently met diagnostic criteria for hemophagocytic lymphohistiocytosis (HLH). PCGDTCL is an aggressive, HLH-associated lymphoma requiring different management than SPTCL and SLL. This case illustrates how PCGDTCL can co-exist with B-cell lymphoma and resemble panniculitis on biopsies. PCGDTCL and SPTCL should enter the differential diagnosis whenever patients present with the constellation of lobular panniculitis and unexplained cytopenias. In the present case, close clinicopathologic correlation and judicious use of IHC on a small sample allowed for a prompt diagnosis.

Application of Blood Lymphocyte Immunophenotype and TCR Gene Rearrangement in the Diagnosis of CTCL

BACKGROUND

The immunophenotype of peripheral blood lymphocytes and T-cell receptor (TCR) gene rearrangement of cutaneous T cell lymphoma (CTCL) patients were retrospectively analyzed to explore their value in the diagnosis of CTCL.

METHODS

A total of fifty patients' results were enrolled from 2013 to 2021, including 29 malignant skin disorders and 21 benign skin disorders. The immunophenotype of peripheral blood lymphocytes were analyzed by flow cytometry and TCR gene rearrangement was detected by capillary electrophoresis. Lymphocyte subsets, CD4/CD8 ratio, the percentage of CD3+CD4+CD7- cells and CD45RA/CD45RO ratio was calculated between malignant and benign skin disorders. Peripheral blood lymphocyte immunophenotype and TCR gene rearrangement was compared with skin biopsy to evaluate their sensitivity and specificity.

RESULTS

Lymphocyte subsets between malignant and benign groups have no significant difference in percentage of T cell (p > 0.05). The CD4/CD8 ratio is higher in patients with malignant lymphoma than the healthy range. The percentage of CD3+CD4+CD7- cells in malignant groups is higher than that in benign groups and CD45RA/ CD45RO ratio has significant difference between malignant and benign groups (p < 0.05). The sensitivity and specificity of TCR rearrangement for CTCL were 51.7% and 42.9%. The sensitivity and specificity of peripheral blood lymphocyte immunophenotype for CTCL were 44.8% and 33.3%. Combining the two methods, the sensitivity and specificity reached 69.0% and 38.1%, respectively.

CONCLUSIONS

CD4/CD8 ratio of lymphocyte subsets, the proportion of CD4+CD7-T cells and CD45RA/CD45RO ratio can effectively distinguish benign and malignant dermatosis. TCR rearrangement method combined with lymphocyte immunophenotype can improve the sensitivity and specificity of CTCL diagnosis.

Differential diagnosis between cutaneous lymphoma and pseudolymphoma

Differential diagnosis of cutaneous lymphoproliferative disorders represents one of the most vexing problems in dermatology and dermatopathology. For nearly a century the diagnosis has been based only upon clinicopathologic correlation. Immunohistochemical and molecular techniques developed during the last 3 decades added new criteria for the differentiation of these diseases. The purpose of this articles is to summarize the criteria for the differential diagnosis of benign vs. malignant lymphoid infiltrates of the skin. In this context, a proper classification of cutaneous lymphoproliferative disorders can be achieved only by a synthesis of clinical, histopathologic, immunophenotypic and molecular criteria, and in some cases only follow-up data allow a precise diagnosis to be made.

Clinical pathway for melanoma detection using comprehensive cutaneous analysis with Melanoscan

The usefulness of a comprehensive cutaneous photography system (Melanoscan) was tested using the following parameters: 1) decision to screen pathway, 2) clinical pathway, 3) clinical outcome, and 4) patient acceptance. The results indicate that 55 percent of those with criteria for scanning were reimbursed by insurance (AMA CTP category 1 code status 96904 for total body photography). In this model of whole body scanning, the ratio of time demand on physicians, patients, and technicians is 1:8:12. In 53 patients, 394 lesions of concern were identified. Of these lesions, 48 (12.31%) were scars, 306 (78.46%) were changed, and 36 (9.23%) were new. The decision to biopsy was made for 18 of the 394 lesions analyzed in the follow-up studies. Sensitivity of the process in determining malignant lesions is 75.00 percent and specificity is 73.70 percent. Preliminary results suggest that change detection analysis reduces the number of biopsies and improves diagnostic accuracy. Assessment of survey results revealed a high degree of patient satisfaction with ease of following Melanoscan directions (81.25%), as well as overall satisfaction with the process (73.44%). These results suggest that whole body screening using the Melanoscan provides a device in which accuracy of lesion tracking, patient confidence in lesion documentation, and clinician time are optimized.

Various faces of Hansen's disease

Leprosy is a chronic granulomatous disease caused by Mycobacterium leproe. Leprosy once considered a taboo is still misdiagnosed and underdiagnosed. In many cases leprosy is treated as common disorders like psoriasis, pyoderma, angioedema, pre vitiligo. Leprosy can present in many diverse ways which can be confused with many treatable and non treatable, infectious and non infectious forms. Leprosy is considered on the verge of elimination. But Leprosy cases are being newly diagnosed day by day. Here we are presenting 4 atypical cases of leprosy which did not seem to have classical presentation but were diagnosed as leprosy when investigated.

Granulomatous slack skin: case report with electron microscopic features

Granulomatous slack skin (GSS) is a rare subtype of mycosis fungoides. It usually presents as slowly evolving, erythematous, slack plaques that usually involve folds of lax skin. Herein, we report a case of GSS and we show electron microscopy examination. Atypical T cells with convoluted and cerebriform nuclei, lymphophagocytosis, and elastophagocytosis are key features of GSS under electron microscopy.

An unusual cause of abdominal pain

We report a case of subcutaneous panniculitis-like T-cell lymphoma (SPTCL) (they are always alpha/beta) in a 36-year-old male who presented with a 6-week history of abdominal pain, fever and significant weight loss. Definitive diagnosis required a full thickness skin biopsy with PCR analysis for clonal T-cell gene arrangement. A literature search showed that SPTCL is a very rare cutaneous lymphoma limited to case reports.

A Rare Case of Cutaneous Intravascular NK/T-Cell Lymphoma

BACKGROUND

Cutaneous intravascular NK/T cell lymphoma (CIVNKTC) is a rare form of extranodal non-Hodgkin's lymphoma with its unique histological and immunophenotypic characteristics.

METHODS

We report a case presenting with an over 2-month history of nodules on the extremities and trunk with intermittent fever. Skin biopsy was taken from the patient and a histopathological examination was made from the material.

RESULTS

The histopathological examination showed some expanding vessels filled with atypical lymphoid cells in the dermis and subcutaneous tissue. The tumor cells had large nuclei and one or two small nucleoli, with the expression of CD3, cytotoxic protein, and Epstein-Barr virus (EBV)-encoded messenger RNAs (EBER), and without the expression of tumor cytokeratin (CK), CD20, CD79A, CD4, and CD8. After being diagnosed as CIVNKTC and treated with a CHOP regimen 6 times, the patient died of this disease 1 year later.

CONCLUSIONS

The clinical course is dangerous and the prognosis is extremely poor.

Classifications of cutaneous lymphomas and lymphoproliferative disorders: An update from the EORTC cutaneous lymphoma histopathology group

The classification of primary cutaneous lymphomas and lymphoproliferative disorders (LPD) is continuously evolving by integrating novel clinical, pathological and molecular data. Recently two new classifications for haematological malignancies including entities of cutaneous lymphomas were proposed: the 5th edition of the WHO classification of haematolymphoid tumours and the International Consensus Classification (ICC) of mature lymphoid neoplasms. This article provides an overview of the changes introduced in these two classifications compared to the previous WHO classification. The main changes shared by both classifications include the downgrading of CD8+ acral T-cell lymphoma to CD8+ acral T-cell LPD, and the recognition of entities that were previously categorized as provisional and have now been designated as definite types including primary cutaneous small or medium CD4+ T-cell LPD, primary cutaneous gamma/delta T-cell lymphoma, primary cutaneous CD8+ aggressive epidermotropic cytotoxic T-cell lymphoma, Epstein-Barr virus-positive mucocutaneous ulcer. Both classifications consider primary cutaneous marginal zone B-cell clonal neoplasm as an indolent disease but use a different terminology: primary cutaneous marginal zone lymphoma (WHO) and primary cutaneous marginal zone LPD (ICC). The 5th WHO classification further introduces and provides essential and desirable diagnostic criteria for each disease type and includes chapters on reactive B- or T-cell rich lymphoid proliferations formerly referred as cutaneous pseudolymphomas, as well as histiocyte and CD8 T-cell rich LPD in patients with inborn error of immunity. As already emphasized in previous lymphoma classifications, the importance of integrating clinical, histological, phenotypic and molecular features remains the crucial conceptual base for defining cutaneous (and extracutaneous) lymphomas.

Pathophysiology of cutaneous T-cell lymphomas: Perspective from a French referral centre

Cutaneous T-cell lymphomas (CTCL) are a diverse group of malignant blood disorders characterized by initial skin infiltration, and sometimes, tumor spreading to lymph nodes, blood, and viscera. Mycosis fungoides is the most common form. Sézary syndrome is a distinctive form of CTCL marked by a significant presence of circulating tumor cells in peripheral blood. These diseases are characterized by the plasticity and heterogeneity of the tumor cells in the different tissue compartments, and a difficulty in identifying these tumor cells for diagnostic purposes and therapeutic monitoring. Progress has been made in the understanding of the pathophysiology of these diseases in recent years, and we provide here a review of these advancements.