Prognostic factors for primary cutaneous anaplastic large-cell lymphoma: a multicentre retrospective study from Japan.

BACKGROUND: The clinical implications of DUSP22 rearrangement and the association between DUSP22 rearrangement and lymphoid enhancer-binding factor 1 (LEF1) expression pattern in CD30+ cutaneous T-cell lymphomas (CTCLs) are unknown. OBJECTIVES: This study assessed the incidence of DUSP22 rearrangement and its clinical and immunohistochemical implications in primary cutaneous anaplastic large-cell lymphoma (pcALCL), lymphomatoid papulosis (LyP) and CD30+ mycosis fungoides with large-cell transformation (MF-LCT), focusing especially on the association with the prognosis and LEF1 expression pattern. Prognostic factors of pcALCL were also examined. METHODS: We conducted a multicentre retrospective study including patients with pcALCL, LyP and MF-LCT diagnosed between 1 January 2000 and 31 December 2018 in Japan. Baseline data at diagnosis, treatment course, overall survival (OS) and disease-specific survival (DSS) were collected. Immunohistochemical analysis and fluorescence in situ hybridization to detect DUSP22 and TP63 rearrangement were performed using skin samples at diagnosis. We investigated the association between staining pattern and these gene rearrangements. We also assessed the prognostic implications of clinical status, immunohistochemical results and the presence of gene rearrangements. RESULTS: DUSP22 rearrangement was detected in 50% (11 of 22) of cases of pcALCL, but not in any cases with LyP (0 of 14) or MF-LCT (0 of 11). TP63 rearrangement was not detected in any case. Clinically, patients with pcALCL with DUSP22 rearrangement did not tend to develop ulcers (P = 0.081). There was no significant association between DUSP22 rearrangement status and immunohistochemical results, including LEF1 expression pattern. T3 stage and the presence of lower limb lesions were significantly associated with shorter OS (P = 0.012 and 0.021, respectively, by log-rank test). Similarly, they were significantly correlated with shorter DSS (P = 0.016 and 0.0001, respectively). CONCLUSIONS: DUSP22 rearrangement is relatively specific to pcALCL among CD30+ CTCLs in Japan. Although the LEF1 expression pattern was not related to DUSP22 rearrangement in pcALCL, there was no rearrangement if LEF1 was not expressed. We confirmed that T3 stage and the lower limb involvement were significantly associated with decreased OS and DSS. The presence or absence of lower limb lesions should be included in T-stage subcategorization in the future.

Enhanced PD-L1 expression on tumor cells in primary CD30-positive cutaneous large T-cell lymphoma: a report of lymph node lesions of four cases.

Scarce data are available regarding neoplastic PD-L1 (nPD-L1, clone SP142) expression in cutaneous T-cell lymphoma. We recently documented a possible association of increased nPD-L1 expression with tumor progression to secondary nodal involvement in two cases of CD30-positive primary cutaneous large T-cell lymphoma (PC-LTCL) (Pathol Int 2020;70:804). Notably, the nodal sites exhibited classic Hodgkin lymphoma (CHL) mimicry related to both morphology and tumor microenvironment (TME), i.e., abundant PD-L1-positive tumor-associated macrophages and low-level PD-1 expression on T-cells. Immunohistochemistry highlighted distinctly different nPD-L1 positivity between the cutaneous and nodal lesions. In the present study, we aimed to validate this unique phenomenon in a larger series of four cases with FISH and targeted-capture sequencing (targeted-seq) analysis. We retrospectively identified two more cases of CD30-positive PC-LTCL with secondary nodal involvement among all patients consecutively diagnosed between 2001-2021. All cases immunohistochemically exhibited elevated nPD-L1 expression on ≥50% of lymphoma cells in nodal tumors, clearly contrasting with the scarce nPD-L1 positivity (≤1%) in cutaneous tumors. Moreover, all nodal lesions exhibited CHL-like TME, with abundant PD-L1-positive tumor-associated macrophages and low-level PD-1 expression on T cells, although the CHL-like morphology was limited in the two original cases. None showed CD274/PD-L1 copy number alteration by FISH analysis, or structural variations of PD-L1 3'-UTR by targeted-seq analysis. These findings indicated that nPD-L1 expression is linked with tumor progression and CHL-like TME in nodal involvement of PC-LTCL. Interestingly, one autopsied case exhibited heterogeneity of nPD-L1 expression at different disease sites.

Safety and efficacy of bexarotene for Japanese patients with cutaneous T-cell lymphoma: Real-world experience from post-marketing surveillance.

To establish real-world evidence about the safety and efficacy of bexarotene for Japanese patients with cutaneous T-cell lymphoma, we conducted a nationwide cohort study using data from post-marketing surveillance for bexarotene treatment. In total, 294 patients with cutaneous T-cell lymphoma were identified between June 2016 and June 2018. Of these, 267 patients were included as the safety analysis set. Of the 267 patients, 175 were included in the efficacy analysis set. Of these, 139 patients had mycosis fungoides, including 46 with early stage disease and 93 with advanced stage disease. Among the 139 patients with mycosis fungoides, the objective response rate was 46.8%. A significant difference in objective response rate was detected between patients who started with bexarotene at 300 mg/m2 (61.6%) and patients who started with bexarotene at less than 300 mg/m2 (22.6%, p < 0.001). Of the 139 patients with mycosis fungoides, 92 were treated with a combination of bexarotene plus photo(chemo)therapy. A significant difference in objective response rate was seen between bexarotene with a combination of photo(chemo)therapy (57.6%) and bexarotene without a combination of photo(chemo)therapy (25.5%, p < 0.001). Starting bexarotene at 300 mg/m2 and combination with photo(chemo)therapy were detected as independent factors influencing response. Common treatment-related adverse events included hypothyroidism (85.8%), hypertriglyceridemia (68.5%), hypercholesterolemia (43.8%), and neutropenia (21.3%). Hypertriglyceridemia, hypercholesterolemia, and neutropenia occurred more frequently in patients who started with bexarotene at 300 mg/m2 than patients who started with bexarotene at less than 300 mg/m2 (hypertriglyceridemia, 76.4% vs. 57.0%, p = 0.001; hypercholesterolemia, 49.0% vs. 36.4%, p = 0.045; neutropenia, 28.0% vs. 12.1%, p = 0.002; respectively). The present study indicates that starting bexarotene at 300 mg/m2 and combination of photo(chemo)therapy offer a promising efficacy for the treatment of patients with mycosis fungoides. Efficacy of low-dose bexarotene plus photo(chemo)therapy should be evaluated in future.

Elevation of circulating neutrophil extracellular traps, interleukin (IL)-8, IL-22, and vascular endothelial growth factor in patients with venomous snake mamushi (Gloydius blomhoffii) bites.

Mamushi bites cause swelling and pain that extend from the bitten site. The coagulopathic, anti-coagulopathic, and vasculopathic actions of mamushi venom result in various laboratory abnormalities, occasionally with muscular, renal, and other organ damage. We investigated the serum biomarkers that were associated with the pathogenesis of mamushi bites, focusing on markers related to tissue-damage and neutrophil activation. Twenty patients (one case of grade 2, 13 cases of grade 3, and six cases of grade 4 of severity) seen by us in one summer season were enrolled. Peripheral blood samples were taken from the patients on day 0, day 2, and day 7 after mamushi bites. In addition to routine blood examination, serum samples were subjected to enzyme-linked immunosorbent assay for citrullinated histone H3 (CitH3), interleukin (IL)-8, IL-17A, IL-22, vascular endothelial growth factor (VEGF), high mobility group box protein 1 (HMGB1), tumor necrosis factor (TNF)-α, and IL-33. Creatinine kinase (CK) values significantly correlated with prothrombin time (PT) levels, suggesting that muscular damage is associated with exaggerated coagulation and fibrinolysis. In the vast majority of patients, HMGB1, TNF-α, and IL-33 were under detection levels. Neutrophil counts did not correlate with PT or CK, indicating that the coagulation disorder and muscular damage were virtually independent of the neutrophil activation. The neutrophil number significantly correlated with CitH3, a representative marker of neutrophil extracellular traps. Moreover, there were significant correlations between neutrophil number, CitH3, IL-8, IL-22, and VEGF. Our study suggests that there are two major cascades in mamushi bites. One is an already characterized venom effect on coagulation, vessels, and muscles. In the other novel cascade, we propose that neutrophil activation with IL-8 leads to the production of IL-22 and VEGF. This sequential event may contribute to both vascular damage and repair.

Outlines of the Japanese guidelines for the management of primary cutaneous lymphomas 2020.

Since the publication of the Japanese "Guidelines for the management of cutaneous lymphomas" in 2011, the World Health Organization (WHO) classification of hematolymphoid neoplasms and the WHO-European Organisation for Research and Treatment of Cancer classification for primary cutaneous lymphomas were updated and a number of novel systemic drugs for cutaneous T-cell lymphoma had been approved in Japan. In 2020, we revised the Japanese guidelines for the management of cutaneous lymphomas with consideration of the recent advances in the understanding of the pathophysiology and classification of cutaneous lymphomas together with the update of treatment strategies reflecting the advent of novel drugs. In addition to a brief explanation of epidemiology, diagnosis, staging system, prognosis and management of each subtype of cutaneous lymphomas, the recommendations for nine clinical questions regarding treatment options that can vary even among experts are also described. A systematic review process and determination of recommendations in answer to each clinical question have been performed in accordance with the Grading of Recommendations, Assessment, Development and Evaluation scheme by a multidisciplinary expert panel consisting of dermatologists, a hematologist and a radiation oncologist. In this article, we present the outlines of the revised Japanese "Guidelines for the management of cutaneous lymphomas".

Suprabasin-null mice retain skin barrier function and show high contact hypersensitivity to nickel upon oral nickel loading.

Suprabasin (SBSN) is expressed not only in epidermis but also in epithelial cells of the upper digestive tract where metals such as nickel are absorbed. We have recently shown that SBSN level is decreased in the stratum corneum and serum of atopic dermatitis (AD) patients, especially in intrinsic AD, which is characterized by metal allergy. By using SBSN-null (Sbsn-/-) mice, this study was conducted to investigate the outcome of SBSN deficiency in relation to AD. Sbsn-/- mice exhibited skin barrier dysfunction on embryonic day 16.5, but after birth, their barrier function was not perturbed despite the presence of ultrastructural changes in stratum corneum and keratohyalin granules. Sbsn-/- mice showed a comparable ovalbumin-specific skin immune response to wild type (WT) mice and rather lower contact hypersensitivity (CHS) responses to haptens than did WT mice. The blood nickel level after oral feeding of nickel was significantly higher in Sbsn-/- mice than in WT mice, and CHS to nickel was elevated in Sbsn-/- mice under nickel-loading condition. Our study suggests that the completely SBSN deficient mice retain normal barrier function, but harbor abnormal upper digestive tract epithelium that promotes nickel absorption and high CHS to nickel, sharing the features of intrinsic AD.

Enhanced PD-L1 expression on tumor cells in primary cutaneous large T-cell lymphoma with CD30 expression as classic Hodgkin lymphoma mimics: A report of lymph node lesions of two cases.

Neoplastic PD-L1 (nPD-L1, clone SP142) expression remains unclear in cutaneous T-cell lymphoma (CTCL), although it is well-documented in classic Hodgkin lymphoma (CHL). Here, we report two cases of primary cutaneous large T-cell lymphoma (PCLTCL) with CD30 expression that developed secondary nodal lesions morphologically mimicking CHL, and describe their PD-L1 expression. Our two cases (52- and 60-year-old males) had long-standing clinical courses of CTCL. Their PCLTCL with CD30 expression developed nodal lesions, having a nodular growth pattern containing scattered CD30+ Hodgkin and Reed-Sternberg-like and/or lacunar cells that expressed CD15 but did not harbor Epstein-Barr virus. Their differential diagnosis from CHL was challenging. A diagnosis of PCLTCL with secondary nodal involvement featuring CHL mimicry was based on comparison of the primary and secondary lesions. In one case, shared expression of the same T-cell antigen was revealed by immunohistochemistry, and in the other, identical clonal TCR rearrangement was demonstrated by polymerase chain reaction (PCR). Interestingly, nPD-L1 was expressed on more than 50% of the tumor cells in the secondary nodal lesions, but on very few in the primary cutaneous lesions, in both cases. This is the first report of nPD-L1 expression greatly increasing with PCLTCL tumor progression to nodal involvement.

Protective role of Galectin-7 for skin barrier impairment in atopic dermatitis.

BACKGROUND: Atopic dermatitis (AD) patients have a barrier disorder in association with Th2 dominant skin inflammation. Galectin-7 (Gal-7), a soluble unglycosylated lectin, is highly expressed in the stratum corneum of AD patients. However, the biological significance of increased Gal-7 expression in AD skin lesions remains unclear. OBJECTIVE: We aimed to investigate the production mechanism and functional role of Gal-7 in AD patients and IL-4/IL-13-stimulated epidermal keratinocytes. METHODS: We assessed the Gal-7 expression levels in skin lesions and sera from AD patients. Gal-7 levels were also measured in monolayered normal human epidermal keratinocytes (NHEKs) and 3-dimensional (3D)-reconstructed epidermis in the presence or absence of IL-4/IL-13 with or without Stat3, Stat6 or Gal-7 gene silencing. RESULTS: Gal-7 was highly expressed in the stratum corneum or intercellular space of AD lesional epidermis as assessed by the stratum corneum proteome analysis and immunohistochemistry. A positive correlation was noted between serum Gal-7 level and transepidermal water loss in patients with AD. These clinical findings were corroborated by our in vitro data, which showed that IL-4/IL-13 facilitated the extracellular release of endogenous Gal-7 in both monolayered NHEKs and 3D-reconstructed epidermis. This machinery was caused by IL-4/IL-13-induced cell damage and inhibited by knockdown of Stat6 but not Stat3 in NHEKs. Moreover, we performed Gal-7 knockdown experiment on 3D-reconstructed epidermis and the result suggested that endogenous Gal-7 serves as a protector from IL-4/IL-13-induced disruption of cell-to-cell adhesion and/or cell-to-extracellular matrix adhesion. CONCLUSION AND CLINICAL RELEVANCE: Our study unveils the characteristic of Gal-7 and its possible role as an alarmin that reflects the IL-4/IL-13-induced skin barrier impairment in AD.

Case series of cutaneous T-cell lymphomas treated with bexarotene-based therapy.

Bexarotene is useful for both early and advanced cutaneous T-cell lymphoma (CTCL), and is sometimes applied to ultraviolet-tolerant early CTCL patients as one of the first-line therapies in the real world. However, continuous administration of bexarotene is sometimes difficult because of its adverse events (AE). Development of an appropriate protocol for bexarotene that can induce a consistent response for CTCL without severe AE (SAE) is needed. We retrospectively investigated 29 Japanese cases of CTCL and evaluated the efficacy of treatment and incident ratios of all AE and SAE. Objective response rate (ORR) for the overall cohort was 65.5%. ORR of the 300 mg/m2 cohort (conventional dose) was 76.2%, while that of the 150-300 mg/body (low dose) with narrowband ultraviolet B light (NBUVB) cohort was 37.5%. Mean event-free survival was 10.0 months for all patients, 6.7 months for the bexarotene conventional-dose cohort and 19.1 months for the low-dose with NBUVB cohort. The incident ratio of total SAE for all patients was 20.7%. The incident ratio of total SAE was 23.8% for the conventional-dose cohort and 12.5% for the low-dose with NBUVB cohort. Our present study suggests that low-dose bexarotene plus NBUVB therapy is well-tolerated and could be one of the optimal therapies for advanced CTCL.

Cutaneous lymphoma in Japan, 2012-2017: A nationwide study.

BACKGROUND: The types of cutaneous lymphoma (CL) and their incidences can vary among geographic areas or ethnic groups. OBJECTIVE: This study aimed to investigate the incidence of various CL types in Japan using epidemiological data from a nationwide registration system for CL. METHODS: A questionnaire was sent to participating hospitals, all of which had been approved to conduct residency programs for board-certified dermatologists by the Japanese Dermatological Association. Data from patients newly diagnosed with CL were collected electronically. RESULTS: Between 2012 and 2017, 2547 new patients with CL from the dermatological institutes were registered. In total, 2090 patients had primary CL and 453 had secondary CL. Those with primary CL included 1609 (77.0 %) patients with mature T- and natural killer (NK)-cell neoplasms, 442 (21.1 %) with B-cell neoplasms, and 39 (1.9 %) with blastic plasmacytoid dendritic cell neoplasms. Mycosis fungoides (MF) was the most common CL subtype in the present study (1003 patients, 48.0 %), and 72.4 % of MF patients had early-stage disease, similar to observations in previous studies on other cohorts. Primary cutaneous CD30+ T-cell lymphoproliferative disorders and adult T-cell leukemia/lymphoma were the second and third most common subtypes, respectively. CONCLUSION: Compared to that in our previous cohort (2007-2011), the number of registered T- and NK-cell CL cases decreased, whereas that of B-cell CL cases increased from 44.8-73.7 patients/year. These results provide insight into CL trends within the Japanese population, which might contribute to a better understanding of the disease.

An intuitive explanation of dermoscopic structures by digitally reconstructed pathological horizontal top-down view images.

Dermoscopy is a convenient tool to diagnose melanocytic lesions, especially nevus and melanoma. Various pigmented structures, including pigment network, dots and globules, and streaks, are observed in dermoscopy. Usually, 2D vertical images are used to explain the correlation of dermoscopy and histopathology. However, because the image of dermoscopy is horizontal, it is difficult for the horizontal view of dermoscopy to refer to the vertical view of histopathology. In our study, we digitally reconstructed 2D horizontal top-down view images and 3D aerial images from 50-100 serial 2D vertical sections by using high-speed scanner and 3D software in 6 cases of melanocytic lesion. Our new technology intuitively explained the histopathological structures corresponding to the dermoscopic structures. This technique could be used as a good educational tool for beginners.