Cutaneous Reactions in Pediatric Patients Treated with MEK Inhibitors: A Retrospective Single-Center Study.

INTRODUCTION: Mitogen-activated extracellular signal-regulated kinase (MEK) inhibitors are in use for several indications for adults and children. Cutaneous toxicities are among the most common adverse effects. We aimed to describe the spectrum of cutaneous adverse events, its frequency, and severity in a cohort of pediatric patients. METHODS: We reviewed all records of patients in our tertiary treatment center treated with MEK inhibitors between January 2016 and January 2023 for all indications. RESULTS: Among 33 patients, 76% reported cutaneous adverse effects. The highest prevalence was in the group of patients treated with trametinib (90%), followed by the group treated with selumetinib (50%) and the group treated with a combination of trametinib and B-Raf proto-oncogene serine/threonine-protein kinase inhibitor (dabrafenib, 34%). Xerosis, dermatitis, paronychia, and hair heterochromia were most frequently reported. Severity was graded 1 or 2 for most adverse events, and 237 visits to the dermatology clinic related to these adverse events were recorded. CONCLUSIONS: Cutaneous adverse events are common in the pediatric population as in adults, but the clinical spectrum is different. Although considered mild, multiple dermatological consultations reflect the distress caused by these events. Dermatologists have a central role in the multidisciplinary care of pediatric patients receiving these agents.

Real-world study on the use of pegylated interferon alpha-2a for treatment of mycosis fungoides/Sézary syndrome using Time to Next Treatment as a measure of clinical benefit: An EORTC CLTG study.

INTRODUCTION: Mycosis fungoides (MF) and Sézary syndrome (SS) are chronic malignant diseases that typically necessitate diverse strategies to achieve remission. Systemic interferon alpha (IFN-α, subtypes 2a and 2b) has been used for MF/SS since 1984, however its production was recently stopped and so the recombinant pegylated (PEG) form of IFN α-2a remains as single IFN alternative treatment, even though not approved for MF/SS. OBJECTIVE: To assess effectiveness and safety of PEG IFN α-2a in monotherapy and in combination with other treatments using time to next treatment (TTNT) as a measure of clinical therapeutic benefit in real world setting. METHODS: We conducted an international and multicenter retrospective study of patients with MF and SS at any stage, treated with PEG IFN α-2a, from July 2012 to February 2022. Patients were included across 11 centers in 10 countries. Primary endpoints were to determine TTNT of PEG IFN α-2a and the adverse events (AE) in MF/SS. RESULTS: In total 105 patients were included, mean age was 61 (22-86 years); 42 (40%) with disease stage IA-IIA, 63 (60%) with stage IIB-IVB. PEG IFN α-2a was combined with other therapies in 67 (64%) patients, usually with extracorporeal photopheresis (36%) and bexarotene (22%). Fifty-seven percent of stage I-IIA patients achieved ORR, whereas 51% of stage IIB-IVB. Combination therapy showed a TTNT of 10.4 months, while 7 months in monotherapy (p=0.0099). Overall, TTNT was 9.2 months, ORR was 53% (56/105), CR and PR were 13% and 40%, respectively.AE were described in 69% (72) of the patients. Flu-like symptoms (27%), lymphopenia (23%) and elevated liver function (10%) were the most frequently reported. Grade 3-4 adverse events were reported in 23 (21%) patients, which were mostly related to myelosuppression. LIMITATIONS: retrospective data analysis and unrestricted number of combination therapies. CONCLUSIONS: PEG IFN α-2a for MF/SS showed ORR of 53%, TTNT of 9.2 months, superiority of combination regimens in comparison to monotherapy and doses of 180 mcg/weekly related to higher ORR.

mAb14, a Monoclonal Antibody against Cell Surface PCNA: A Potential Tool for Sezary Syndrome Diagnosis and Targeted Immunotherapy.

Mycosis fungoides (MF) and Sézary syndrome (SS) are the most common types of primary cutaneous T-cell lymphoma (CTCL). Proliferating cell nuclear antigen (PCNA) is expressed on the cell surface of cancer cells (csPCNA), but not on normal cells. It functions as an immune checkpoint ligand by interacting with natural killer (NK) cells through the NK inhibitory receptor NKp44, leading to the inhibition of NK cytotoxicity. A monoclonal antibody (mAb14) was established to detect csPCNA on cancer cells and block their interaction with NKp44. In this study, three CTCL cell lines and peripheral blood mononuclear cells (PBMCs) from patients with SS and healthy donors were analyzed for csPCNA using mAb14, compared to monoclonal antibody PC10, against nuclear PCNA (nPCNA). The following assays were used: immunostaining, imaging flow cytometry, flow cytometry, cell sorting, cell cycle analysis, ELISA, and the NK-cell cytotoxic assay. mAb14 successfully detected PCNA on the membrane and in the cytoplasm of viable CTCL cell lines associated with the G2/M phase. In the Sézary PBMCs, csPCNA was expressed on lymphoma cells that had an atypical morphology and not on normal cells. Furthermore, it was not expressed on PBMCs from healthy donors. In the co-culture of peripheral blood NK (pNK) cells with CTCL lines, mAb14 increased the secretion of IFN-γ, indicating the reactivation of pNK activity. However, mAb14 did not enhance the cytotoxic activity of pNK cells against CTCL cell lines. The unique expression of csPCNA detected by mAb14 suggests that csPCNA and mAb14 may serve as a potential biomarker and tool, respectively, for detecting malignant cells in SS and possibly other CTCL variants.

Mycosis Fungoides in Solid-Organ Transplant Recipients: A Multicenter Retrospective Cohort Study.

BACKGROUND: Mycosis fungoides (MF) in solid-organ transplant recipients (SOTRs) is rare, with limited data on disease characteristics. OBJECTIVE: The aim was to study the characteristics of MF in SOTRs with an emphasis on the immunosuppressive therapy. METHODS: A retrospective cohort of patients diagnosed with MF, who were also SOTRs, were followed at 3 cutaneous lymphoma outpatient clinics, between January 2010 and February 2022. RESULTS: Ten patients were included (7 male; median ages at transplantation and at diagnosis of MF were 33 and 48 years, respectively; 40% were diagnosed before the age of 18 years). Median time from transplantation to diagnosis of MF was 8 years (range 0.5-22). Transplanted organs and immunosuppressive treatments included: liver (n = 5; 4 treated with tacrolimus, 1 with tacrolimus and prednisone), kidney (n = 3), liver and kidney (n = 1), and heart (n = 1), all treated with mycophenolic acid, tacrolimus, and prednisone. Nine had early-stage MF (IA - 4, IB - 5; 40% with early folliculotropic MF), treated with skin-directed therapies, in 2 combined with acitretin, achieving partial/complete response. One patient had advanced-stage MF (IIIA) with folliculotropic erythroderma, treated with ultraviolet A and narrow-band ultraviolet B with acitretin, achieving partial response. Immunosuppression was modified in 3. At last follow-up (median 4 years, range 1-8), no stage progression was observed; 5 had no evidence of disease, 5 had active disease (IA/IB - 4, III - 1). CONCLUSIONS: MF in SOTRs is usually diagnosed at an early stage, with overrepresentation of folliculotropic MF, and of children. Immunosuppressive therapy alterations, not conducted in most patients, should be balanced against the risk of organ compromise/rejection. Disease course was similar to MF in immunocompetent patients, during the limited time of follow-up.

New Insights into Macular Type of Primary Cutaneous B-Cell Lymphoma: Extension of the Clinical and Histopathological Patterns.

BACKGROUND: Primary cutaneous B-cell lymphoma (PCBCL) classically presents with papules, plaques, and nodules/tumors. Previous reports of PCBCL manifesting with macular lesions are scarce and focused on primary cutaneous follicle-center cell lymphoma (PCFCL). OBJECTIVES: The objective of this study was to report our experience with PCBCL presenting with erythematous macules. METHODS: Patients with low-grade PCBCL manifesting with erythematous patches, diagnosed and managed between January 2000 through December 2019 at 2 tertiary cutaneous-lymphoma outpatient clinics, were included. Clinical data were retrospectively collected, and biopsy specimens of the macules, and if present of the typical nodular/tumoral lesions, were reviewed. RESULTS: There were 14 patients, aged 16-67 years, 8 had PCFCL and 6 marginal zone lymphoma (PCMZL). All had 1-15 cm erythematous macules, mimicking: interstitial granuloma annulare/vascular tumors/early-stage folliculotropic mycosis fungoides, or presenting with figurate erythema or livedo reticularis-like/net-like pattern. In 3 patients, macules were the presenting lesions, in 2 as the sole manifestation, whereas in 12 patients, typical PCBCL lesions were observed during disease course. The macules showed in all, superficial and deep perivascular infiltrates, and in most, periadnexal infiltrates. Micronodules were observed in 11 specimens, with nodular infiltrates also observed in 4. B cells comprised the majority of the lymphocytes in only 4. Seven of 11 cases tested showed immunoglobulin heavy chain monoclonality. CONCLUSIONS: PCMZL and PCFCL may manifest with erythematous macules. Physicians should be aware of this unusual manifestation of low-grade PCBCL, which may represent a clinicopathological diagnostic pitfall.

New developments in skin-directed treatments of cutaneous T-cell lymphoma.

The therapeutic approach for mycosis fungoides, the most common type of primary cutaneous T-cell lymphoma, is based mainly on the stage of the disease, and skin-directed treatment is recommended by all international guidelines as the first-line of treatment for early-stage disease. Skin-directed treatments may be also given in combination with systemic therapies in early-stage mycosis fungoides patients recalcitrant to different types of skin-directed treatments, or in certain patients with high-risk features. Advanced-stage mycosis fungoides is treated mainly with systemic treatments, which may be combined with skin-directed treatments. Due to the rarity of mycosis fungoides, controlled clinical trials of the different skin-directed treatment modalities are almost non-existent, with a few exceptions, and therefore recommendations are largely based on cohort studies and expert opinion. This paper reviews the new developments in skin-directed treatments and provides an update on new studies of already well-known therapies, and an update on novel treatments.

Facial demodicosis in the immunosuppressed state: a retrospective case series from a tertiary referral center.

BACKGROUND: Data on Demodex in the immunosuppressed state is limited, focusing mainly on patients with human immunodeficiency virus and hematological malignancies. The aim of this study was to describe the manifestations of facial demodicosis in diverse immunosuppressive states. METHODS: The medical records of all patients followed at a Demodex outpatient clinic of a tertiary medical center from January 2008 to November 2020 were retrospectively reviewed. Data on patients who were immunosuppressed while with demodicosis were retrieved. RESULTS: The cohort included 28 patients (17 women and 11 men; median age, 58 years). Types of immunosuppression included treatments with hydroxyurea for polycythemia vera/essential thrombocytosis, mycophenolic acid, tacrolimus, and prednisone for liver and/or kidney transplantation, prednisone with cyclosporine/methotrexate/azathioprine/rituximab mainly for autoimmune diseases, mercaptopurine with/without anti-tumor necrosis factor alpha (TNF-α) for Crohn's disease, chemotherapy for neoplasms, anti-TNF-α for psoriasis, and Cushing's syndrome. The clinical types of demodicosis included: papulopustular, erythematotelangiectatic and fulminant rosacea, hyperpigmented, pityriasis folliculorum, pustular folliculitis, and dermatitis. The diverse clinical presentations led to various differential diagnoses. Topical treatment with ivermectin (monotherapy/combination with other treatments) was effective. CONCLUSION: Clinicians treating immunosuppressed patients should be familiar with the different forms of demodicosis and include them in the differential diagnosis of facial eruptions.

Real-life experience with chlormethine gel for early-stage mycosis fungoides with emphasis on types and management of cutaneous side-effects.

BACKGROUND: Real-life efficacy data on the recently approved once daily application of chlormethine gel (CG) for mycosis fungoides (MF) is limited, and detailed characterization of the side effects and their management are strikingly sparse. OBJECTIVE: To evaluate the efficacy and particularly the side effect profile of CG in early-stage MF patients in a real-life setting. METHODS: We performed a single-center retrospective analysis of 66 early-stage MF adult patients treated with CG in 2016-2019. RESULTS: Treatment with a once-daily application (52%), or at lower frequencies (48%), in some with topical corticosteroids (TCS) (40%), resulted in an overall response rate of 50%, with no significant difference between stage IA and IB. Cutaneous side effects (56%) included irritant or allergic contact dermatitis (36%, mostly mild/moderate and manageable by reducing application frequency and/or adding TCS or interrupting treatment), unmasking effect (9%), hyperpigmentation (14%), and pruritus (9%). Withdrawal due to side effects occurred in 19.6% of patients (15% for contact dermatitis). CONCLUSION: In real-life management, flexible regimens of CG sometimes with TCS, show efficacy in early-stage MF and may reduce the rate of contact dermatitis, the main treatment-limiting side effect. Practical recommendations with emphasis of the types, time of appearance, and management of side effects are provided.

Clinical approach to skin eruptions induced by anti-TNF agents among patients with inflammatory bowel diseases: insights from a multidisciplinary IBD-DERMA clinic.

BACKGROUND AND AIMS: Skin eruptions are prevalent among patients with inflammatory bowel diseases (IBD), often associated with therapies and frequently leading to dermatological consults and treatment interruptions. We aimed to assess the impact of joint shared decision-making in a multidisciplinary (MDT) IBD-DERMA clinic. METHODS: This retrospective cohort study assessed a consecutive group of patients with IBD who were referred for consultation in an MDT clinic at a tertiary referral center in Israel. RESULTS: Over 1 year, 118 patients were evaluated in the MDT-IBD-DERMA clinic: 68 (57.6%) males; age - 35.2 ±â€„13.5 years, disease duration - 7.1 (interquartile range: 3.7-13.9) years; Crohn's disease - 94/118 (79.6%). Skin eruption induced by an anti-tumor necrosis factor (TNF) were the most common diagnoses [46/118 (39%)], including psoriasiform dermatitis (PD) - 31/46 (67.4%) and inflammatory alopecia (IA) - 15/46 (32.6%). Of these, 18 patients (39.1%) continued the anti-TNF agent concomitantly with a topical or systemic anti-inflammatory agent to control the eruption. The remaining 28 patients (60.9%) discontinued the anti-TNF, of whom 16/28 (57.1%) switched to ustekinumab. These strategies effectively treated the majority [38/46 (82.6%)] of patients. Continuation of the anti-TNF was possible in a significantly higher proportion of patients with PD: 12/31 (38.7%) than only one in the IA group, p = 0.035. There was a higher switch to ustekinumab among the IA 7/15 (46.6%) compared with the PD 7/31 (22.6%) group, P = .09. Following IBD-DERMA advised intervention, IBD deteriorated in 9/4 6(19.5%) patients, 5/9 on ustekinumab (PD versus IA, P = NS). CONCLUSION: Shared decision-making in an integrated IBD-DERMA clinic allowed successful control of skin eruptions while preserving control of the underlying IBD in more than 80% of cases. Patients with IA profited from a switch to ustekinumab.

Prophylactic Topical Treatment for EGFR Inhibitor-Induced Papulopustular Rash: A Randomized Clinical Trial.

BACKGROUND: The incidence of epidermal growth factor receptor inhibitor (EGFRI)-induced papulopustular rash is 60-85%. OBJECTIVE: To investigate prophylactic topical treatment for EGFRI-induced rash. METHODS: A single-center, randomized, double-blind, placebo-controlled trial. Adult cancer patients initiating treatment with EGFRIs were randomized to receive facial topical treatment with chloramphenicol 3% + prednisolone 0.5% (CHL-PRED) ointment, chloramphenicol 3% (CHL) ointment, or aqua cream (AQUA). The primary end points were the incidence of ≥grade 3 rash using the Common Terminology Criteria for Adverse Events (CTCAE), on days 14 and 30. A subanalysis was conducted for incidence of a protocol-specified significant rash, defined as ≥10 facial papulopustular lesions. RESULTS: The per-protocol analysis on day 14 included 69 patients, who received CHL-PRED (21), CHL (23), or AQUA (25). The incidence of CTCAE ≥grade 3 rash was not statistically significant between arms; however, the incidence of the protocol-specified significant rash was: CHL-PRED 14%, CHL 39%, and AQUA 48% (p = 0.03, CHL-PRED vs. AQUA). At 30 days, the CTCAE ≥grade 3 incidence was similar, but the incidences of protocol-specified significant rash were 6%, 16%, and 43% (p = 0.03, CHL-PRED vs. AQUA). No significant differences were found between CHL and CHL-PRED and between CHL and AQUA. CONCLUSIONS: Prophylactic topical CHL-PRED was efficacious when compared to AQUA, in the treatment of EGFRI-induced facial papulopustular rash.

The trichoscopic features of hair shaft anomalies induced by epidermal growth factor receptor inhibitors: A case series.

BACKGROUND: Although the clinical hair changes that occur under treatment with epidermal growth factor receptor inhibitors (EGFRIs) are documented, their trichoscopic features have not been reported. OBJECTIVE: To evaluate the trichoscopic findings in scalp and facial hair, induced by EGFRI treatment. METHODS: Patients treated with EGFRIs at a tertiary oncodermatology clinic in 2015 through 2017 were evaluated for macroscopic and trichoscopic changes. RESULTS: The cohort included 23 patients (13 women; median age, 68 years) treated with EGFRIs for an average of 13 months (range, 2-40 months). Macroscopically, 18 patients (78%) had dry, lusterless, coarse, kinky, brittle scalp hair, and 17 (74%) had trichomegaly of the eyebrows/eyelashes. Trichoscopic findings were of hair shaft anomalies including pili torti, affecting scalp hair in 20 patients (87%), eyebrows in 6 (26%), and eyelashes in 8 (50%), and asymmetric hyperpigmented fusiform widening of hair scalp in 3 (13%), eyebrows in 10 (43%), and eyelashes in 4 (25%). Dermoscopic findings of the peri- and interfollicular skin were scale, whitish erythematous structureless areas, and branching vessels. LIMITATIONS: Lack of trichoscopic-histologic correlation, lack of baseline examination. CONCLUSION: The trichoscopic correlates of the macroscopic hair changes under EFGRI treatment include pili torti, and asymmetric hyperpigmented fusiform widening, with dermoscopic cutaneous manifestations of scale, whitish erythematous structureless areas, and branching vessels.

Cancer-Associated Fibroblasts in Mycosis Fungoides Promote Tumor Cell Migration and Drug Resistance through CXCL12/CXCR4.

Cancer cells are known to reprogram normal fibroblasts into cancer-associated fibroblasts (CAFs) to act as tumor supporters. The presence and role of CAFs in mycosis fungoides (MF), the most common type of cutaneous T-cell lymphoma, are unknown. This study sought to characterize CAFs in MF and their cross talk with the lymphoma cells using primary fibroblast cultures from punch biopsies of patients with early-stage MF and healthy subjects. MF cultures yielded significantly increased levels of FAPα, a CAF marker, and CAF-associated genes and proteins: CXCL12 (ligand of CXCR4 expressed on MF cells), collagen XI, and matrix metalloproteinase 2. Cultured MF fibroblasts showed greater proliferation than normal fibroblasts in ex vivo experiments. A coculture with MyLa cells (MF cell line) increased normal fibroblast growth, reduced the sensitivity of MyLa cells to doxorubicin, and enhanced their migration. Inhibiting the CXCL12/CXCR4 axis increased doxorubicin-induced apoptosis of MyLa cells and reduced MyLa cell motility. Our data suggest that the fibroblasts in MF lesions are more proliferative than fibroblasts in normal skin and that CAFs protect MF cells from doxorubicin-induced cell death and increase their migration through the secretion of CXCL12. Reversing the CAF-mediated tumor microenvironment in MF may improve the efficiency of anticancer therapy.

Melanoma Risk is Increased in Patients with Mycosis Fungoides Compared with Patients with Psoriasis and the General Population.

Patients with mycosis fungoides (MF) are thought to be at increased risk of melanoma. However, studies addressing surveillance-bias and treatments as a possible confounder are lacking. This retrospective study compared the prevalence and risk of melanoma between 982 patients with MF, and 3,165 patients with psoriasis attending tertiary cutaneous-lymphoma/psoriasis clinics during 2009 to 2018. Melanoma was diagnosed in 47 patients with MF (4.8%; 43 early-stage) and in 23 patients with psoriasis (0.7%) (odds ratio 6.6, p < 0.0001). In 60% of patients, MF/psoriasis preceded melanoma diagnosis. Hazard ratio (HR) for a subsequent melanoma in MF vs psoriasis was 6.3 (95% confidence interval (95% CI) 3.4-11.7, p < 0.0001). Compared with the general population, melanoma standardized incidence ratios were 17.5 in patients with MF (95% CI 11.0-23.9, p < 0.0001), and 2.2 (95% CI 0.6-3.8, p = 0.148) in patients with psoriasis. Narrow-band ultraviolet B was not a contributory factor (HR 1.15, 95% CI 0.62-2.14, p = 0.66). These findings add evidence that patients with MF have a significantly higher risk of melanoma, not only compared with the general population, but also compared with patients with psoriasis. This comorbidity may be inherent to MF.

The Course of Mycosis Fungoides under Cytokine Pathway Blockers: A Multicentre Analysis of Real-life Clinical Data.

Literature regarding the effect of biologics on the course of mycosis fungoides (MF) is scarce. This multicentre study analysed retrospective data on 19 patients with MF, who were treated with biologics; 12 for inflammatory conditions coexisting with MF, and 7 for MF misdiagnosed as an inflammatory skin disease. Eight patients were treated with anti-tumour necrosis factor-α-monotherapy; 6 had early-stage MF, in 3 patients MF preceded and in 3 MF was diagnosed after initiation of biologics, with no stage-progression or with stable disease, respectively (median treatment time concurrent with MF 57 months). Two patients had advanced stage MF: IIB, treated for 15 months with no stage-progression, and IVA1, treated for 8 months, died of disease 10 months later. The other 11/19 patients received anti-interleukin-17A and/or anti-interleukin-12/23 or anti-interleukin-23 (with/without anti-tumour necrosis factor-α/anti-interleukin-4/13), with stage-progression in 8 patients after a median of 8 months' treatment. Although, in general, biologics should be avoided in patients with MF, these results indicate that anti-tumour necrosis factor-α-monotherapy might not aggravate the disease course in early-stage patients. Interleukin-17A, interleukin-12/23 and interleukin-23 pathway-blockers may prompt progression of MF.

Stage-dependent Increase in Expression of miR-155 and Ki-67 and Number of Tumour-associated Inflammatory Cells in Folliculotropic Mycosis Fungoides.

Recent studies suggest that folliculotropic mycosis fungoides (FMF), the most common variant of mycosis fungoides (MF), presents with 2 distinct clinicopathological stages: early indolent stage and more aggressive advanced/tumour stage. To further characterize these stages, miR-155 expression was studied with qRT-PCR and found to be significantly higher in biopsies of tumour-stage FMF compared with early-stage FMF and inflammatory dermatoses. There was no statistically significant difference in miR-155 expression between early-stage FMF and early-stage MF, nor between tumour-stage FMF and tumour-stage MF. Immunohistochemical analysis revealed a significantly increased number of dermal Ki-67+ proliferating lymphocytes in tumour-stage FMF, together with an increased number of CD20+ B cells and CD68+ macrophages compared with early-stage FMF. Thus, similar to classic MF, miR-155, Ki-67 tumour cell immunoreactivity, and certain tumour-infiltrating inflammatory cells are differentially expressed in early- vs tumour-stage FMF. The results of this study corroborate the notion that FMF presents with 2 distinct stages.

Synergistic cytotoxic activity of cannabinoids from cannabis sativa against cutaneous T-cell lymphoma (CTCL) in-vitro and ex-vivo.

Cannabis sativa produces hundreds of phytocannabinoids and terpenes. Mycosis fungoides (MF) is the most common type of cutaneous T-cell lymphoma (CTCL), characterized by patches, plaques and tumors. Sézary is a leukemic stage of CTCL presenting with erythroderma and the presence of neoplastic Sézary T-cells in peripheral blood. This study aimed to identify active compounds from whole cannabis extracts and their synergistic mixtures, and to assess respective cytotoxic activity against CTCL cells. Ethanol extracts of C. sativa were analyzed by high-performance liquid chromatography (HPLC) and gas chromatography/mass spectrometry (GC/MS). Cytotoxic activity was determined using the XTT assay on My-La and HuT-78 cell lines as well as peripheral blood lymphocytes from Sézary patients (SPBL). Annexin V assay and fluorescence-activated cell sorting (FACS) were used to determine apoptosis and cell cycle. RNA sequencing and quantitative PCR were used to determine gene expression. Active cannabis compounds presenting high cytotoxic activity on My-La and HuT-78 cell lines were identified in crude extract fractions designated S4 and S5, and their synergistic mixture was specified. This mixture induced cell cycle arrest and cell apoptosis; a relatively selective apoptosis was also recorded on the malignant CD4+CD26- SPBL cells. Significant cytotoxic activity of the corresponding mixture of pure phytocannabinoids further verified genuine interaction between S4 and S5. The gene expression profile was distinct in My-La and HuT-78 cells treated with the S4 and S5 synergistic mixture. We suggest that specifying formulations of synergistic active cannabis compounds and unraveling their modes of action may lead to new cannabis-based therapies.

The Utility of 18F-fluorodeoxyglucose Positron-Emission Tomography/Computed Tomography in Cutaneous B-Cell Lymphoma.

BACKGROUND: Whole-body integrated positron emission tomography / contrast-enhanced computed tomography (PET/CT) scan is increasingly used in cutaneous lymphomas. However, the value of PET/CT in the detection of cutaneous lesions in primary cutaneous B-cell lymphoma (PCBCL) has barely been investigated. OBJECTIVES: To investigate the diagnostic accuracy of PET/CT in tracking cutaneous involvement in PCBCL. METHODS: A retrospective study was conducted on 35 consecutive patients diagnosed with cutaneous B-cell lymphoma according to the World Health Organization classification who were evaluated with PET/CT as the initial staging procedure before treatment. RESULTS: Thirty-five patients met the study criteria. In two patients extracutaneous disease was detected by PET/CT and CT and confirmed by biopsy. Of the 33 patients with PCBCL, 26 (79%) had small cell PCBCL (18 marginal-zone, 8 follicle-center lymphoma) and 7 (21%) had large cell PCBCL (3 follicle-center, 3 leg-type, 1 indeterminate). PET/CT detected skin lesions in 3 of 26 patients (12%) with small-cell PCBCL as compared to 6 of 7 patients with large-cell PCBLC (86%), a 7.4-fold detection risk (95% confidence interval, 2.4-22, P = 0.004). The PET-positive subgroup was characterized by larger lesion size (P < 0.001) and a higher Ki-67 proliferation index (P < 0.001). CONCLUSIONS: The sensitivity of PET/CT for detecting cutaneous involvement of lymphomas is low for small-cell PCBCL but high for large-cell types, and thus may facilitate therapeutic strategies.

Mycosis fungoides: A great imitator.

Mycosis fungoides (MF), the most common cutaneous T-cell lymphoma, typically presents in its early stage as inflammatory erythematous patches or plaques, with epidermotropism as the histopathologic hallmark of the disease. Over the past 30 years, numerous atypical types of MF, which deviate from the classic Alibert-Bazin presentation of the disease, have been described. These variants can simulate a wide variety of benign inflammatory skin disorders either clinically, both clinically and histopathologically, or mainly histopathologically. We have summarized the many faces of the disease, which set MF as a "great imitator," with special focus on the differential diagnosis and its benign mimickers.

IL-17A Inhibitor Switching - Efficacy of Ixekizumab Following Secukinumab Failure. A Single-center Experience.

Interleukin-17A inhibitors are a promising alternative to tumor necrosis factor-α inhibitors for the treatment of psoriasis. In-class switch has been hardly investigated for interleukin-17A inhibitors. We report the experience (2017-2018) of a tertiary medical center with interleukin-17A-inhibitor switch in patients with moderate-to-severe psoriasis. Patient-, disease- and outcome-related data were retrospectively collected from the electronic files of 25 patients switched to ixekizumab following secukinumab failure. Mean ± standard deviation patient age was 56.7 ± 12.2 years. Mean baseline Psoriasis Area and Severity Index was 25. Secukinumab was discontinued due to primary failure in 7 patients and secondary failure in 18. Ixekizumab was administered for 7.3 ± 2.8 months; 22 patients were still on ixekizumab at the end of the study. Mean ± standard deviation Psoriasis Area and Severity Index reduction from baseline at study end was 75.5±20.0%. Patients with moderate-to-severe psoriasis seem to be amenable to treatment with ixekizumab following secukinumab failure. Further large multicenter studies are needed.

Retinoic acid receptor agonist as monotherapy for early-stage mycosis fungoides: does it work?

BACKGROUND: Retinoids exert their biologic effects by binding to intracellular retinoic-acid receptors (RARs) and/or retinoid X receptors (RXRs). Early-stage mycosis fungoides (MF) has been effectively treated with bexarotene, an RXR-agonist, with overall response (OR) rates 54-67% and complete response (CR) rates 7-27%. Data on RAR-agonist monotherapy are limited. OBJECTIVE: To analyze the effectiveness of RAR-agonist monotherapy for early-stage MF. METHODS: Data on patients with early-stage MF treated with acitretin/isotretinoin monotherapy at a tertiary cutaneous lymphoma clinic in 2010-2017 were collected retrospectively from the medical files. RESULTS: Thirty-five patients (26 males) of median age 50 years (range 8-83) with early-stage MF (IA 9, IB 26) underwent 37 treatment events: 25 acitretin and 12 isotretinoin at a median dosages of 0.3 mg/kg (range 0.2-0.9) and 0.2 mg/kg (range 0.1-0.7), respectively. Median time to maximal response was 6 months for both (range 1-10 for acitretin, 3-16 for isotretinoin); median treatment duration was 10 months (range 3-46) for acitretin, and 9 months (range 3-55) for isotretinoin. OR was 64% for acitretin and 80% for isotretinoin, and CR, 4% and 8%, respectively. Side-effect profiles were as previously reported for retinoids. CONCLUSIONS: Early-stage MF patients may benefit from low dose RAR-agonist monotherapy, although the CR rate is low.