MMP1, MMP9, MMP11 and MMP13 in melanoma and its metastasis - key points in understanding the mechanisms and celerity of tumor dissemination.

BACKGROUND: Matrix metalloproteinase (MMP)1, MMP9, MMP11, and MMP13 are overexpressed in malignant melanoma (MM), being associated with tumor invasive phase, metastases, and more aggressive neoplastic phenotypes. AIM: The main objective of the current study was to correlate the expression of the MMPs with the evolution of MM toward distant metastasis. PATIENTS, MATERIALS AND METHODS: We designed a retrospective cohort study, including 13 patients with metastatic MM. Data concerning age, sex, localization of the primary lesion and metastasis, and histological and immunohistochemical features (intensity of expression and percent of positive cells for MMPs) were statistically processed. RESULTS: The time between the diagnosis of primitive melanoma and the diagnosis of metastasis ranged between 0 and 73 months, with a mean value of 18.3 months. The metastases rich in MMP1- and MMP9-positive cells occurred earlier than the metastases with low levels of positive cells. The mean period until metastasis was shorter for the MMP1-expressing tumors than the ones without MMP1 expression. MMP13 expression in the tumor and its metastasis was significantly linked with the time until the metastasis occurrence. CONCLUSIONS: This study emphasizes the roles of MMP1, MMP9, and MMP13 in the process of metastasis in melanoma and the opportunity to use them as therapeutic targets and surveillance molecules.

A New Method of Artificial-Intelligence-Based Automatic Identification of Lymphovascular Invasion in Urothelial Carcinomas.

The presence of lymphovascular invasion (LVI) in urothelial carcinoma (UC) is a poor prognostic finding. This is difficult to identify on routine hematoxylin-eosin (H&E)-stained slides, but considering the costs and time required for examination, immunohistochemical stains for the endothelium are not the recommended diagnostic protocol. We developed an AI-based automated method for LVI identification on H&E-stained slides. We selected two separate groups of UC patients with transurethral resection specimens. Group A had 105 patients (100 with UC; 5 with cystitis); group B had 55 patients (all with high-grade UC; D2-40 and CD34 immunohistochemical stains performed on each block). All the group A slides and 52 H&E cases from group B showing LVI using immunohistochemistry were scanned using an Aperio GT450 automatic scanner. We performed a pixel-per-pixel semantic segmentation of selected areas, and we trained InternImage to identify several classes. The DiceCoefficient and Intersection-over-Union scores for LVI detection using our method were 0.77 and 0.52, respectively. The pathologists' H&E-based evaluation in group B revealed 89.65% specificity, 42.30% sensitivity, 67.27% accuracy, and an F1 score of 0.55, which is much lower than the algorithm's DCC of 0.77. Our model outlines LVI on H&E-stained-slides more effectively than human examiners; thus, it proves a valuable tool for pathologists.

Assessment of RAS-RAF-MAPK Pathway Mutation Status in Healthy Skin, Benign Nevi, and Cutaneous Melanomas: Pilot Study Using Droplet Digital PCR.

In the present study, we employed the ddPCR and IHC techniques to assess the prevalence and roles of RAS and RAF mutations in a small batch of melanoma (n = 22), benign moles (n = 15), and normal skin samples (n = 15). Mutational screening revealed the coexistence of BRAF and NRAS mutations in melanomas and nevi and the occurrence of NRAS G12/G13 variants in healthy skin. All investigated nevi had driver mutations in the BRAF or NRAS genes and elevated p16 protein expression, indicating cell cycle arrest despite an increased mutational burden. BRAF V600 mutations were identified in 54% of melanomas, and NRAS G12/G13 mutations in 50%. The BRAF mutations were associated with the Breslow index (BI) (p = 0.029) and TIL infiltration (p = 0.027), whereas the NRAS mutations correlated with the BI (p = 0.01) and the mitotic index (p = 0.04). Here, we demonstrate that the "young" ddPCR technology is as effective as a CE-IVD marked real-time PCR method for detecting BRAF V600 hotspot mutations in tumor biopsies and recommend it for extended use in clinical settings. Moreover, ddPCR was able to detect low-frequency hotspot mutations, such as NRAS G12/G13, in our tissue specimens, which makes it a promising tool for investigating the mutational landscape of sun-damaged skin, benign nevi, and melanomas in more extensive clinical studies.

Real-World Endoscopic and Histologic Outcomes in Ulcerative Colitis Patients: A Retrospective Cohort Study.

BACKGROUND: Histologic activity has emerged as an aspirational therapeutic goal in ulcerative colitis management. It is not yet a formal treatment target in ulcerative colitis. However, it could be used as an adjunct to mucosal healing to represent a deeper level of healing. We investigated mucosal and histologic remission rates and potential predictors of these outcomes in a cohort of UC patients. METHODS: We conducted a retrospective analysis of data collected from UC patients enrolled in an ongoing prospective cohort study. Mucosal healing was defined as Mayo endoscopic score = 0. RESULTS: A total of 131 patients with ulcerative colitis were enrolled in our study and were prospectively followed for a median length of 2 years (range 0-5 years), totaling 266 study visits. Mucosal healing was recorded for 27 patients at 70 (26%) different study visits. For patients with mucosal healing, histologic remission was achieved in 18/27 (66%) patients. On univariate analysis, sustained clinical remission, SIBDQ scores ≥ 5.5, CRP ≤ 5 mg/dL and absence of corticotherapy were associated with mucosal healing and SIBDQ scores ≥ 5.5 and CRP ≤ 5 mg/dL with histologic healing, respectively. After logistic regression analysis, none of the investigated factors were associated with mucosal and histologic healing. The number of CD8+ intraepithelial lymphocytes (IELs) was significantly greater than the number of CD4+ IELs in periods of disease activity, as well as during mucosal healing (p < 0.01 in both cases). CONCLUSIONS: Mucosal healing and histologic remission rates are low in real-life settings. The results of univariate analysis indicate that a good quality of life (SIBDQ score) and normal inflammatory markers (CRP) are associated with mucosal and histologic healing. However, frequently used patient- and disease-related factors, including mucosal healing, are not reliable predictors for histologic remission. Greater CD8+ lymphocyte involvement and higher CD8+/CD4+ distribution can have a meaningful impact on understanding the pathogenesis and natural history of ulcerative colitis, as well as future treatment options for lymphocyte-targeting medications.

EUS-guided fine needle biopsy is able to provide diagnosis in rare osteoclast-like giant cells undifferentiated carcinoma of the pancreas: report of two cases.

Undifferentiated carcinoma of the pancreas with osteoclast-like giant cells (UC-OGC) is a rare subtype of pancreatic cancer, accounting for less than 1% of all pancreatic tumors. Preoperative diagnosis is cumbersome as cross-sectional imaging is often not capable to distinguish between UC-OGC and other pancreatic tumors such as pancreatic adenocarcinoma, mucinous carcinoma or neuroendocrine tumors and specific tumor markers seem to be lacking. Endoscopic ultrasound r `m(EUS) with tissue acquisition via fine-needle aspiration (FNA) or biopsy (FNB) with microscopic HE staining and immunohistochemistry allows for an accurate diagnosis, thus influencing further treatment. We present herein the cases of two patients with osteoclast-like giant cells tumors of the pancreas diagnosed by EUS-guided fine needle biopsy and perform a literature review on the role of EUS-guided biopsy for diagnosis.

The prognostic significance of the clinical and histological parameters in primary cutaneous melanoma patients.

Cutaneous melanoma is the most aggressive form of skin cancer and its incidence is unfortunately increasing. In the last decades, a progressive increase of new cases of diagnosed thin melanoma has been noted. This may be due to earlier detection, better surveillance, improved diagnostic criteria or increased exposure to sunlight. Despite the fact that Breslow tumor thickness has the strongest proven prognostic significance, there are still thin melanomas that metastasize and thick melanomas with favorable evolution. Therefore, the identification of strong predictive factors for survival is mandatory, particularly for patients with thin melanoma.

A New Artificial Intelligence-Based Method for Identifying Mycobacterium Tuberculosis in Ziehl-Neelsen Stain on Tissue.

Mycobacteria identification is crucial to diagnose tuberculosis. Since the bacillus is very small, finding it in Ziehl-Neelsen (ZN)-stained slides is a long task requiring significant pathologist's effort. We developed an automated (AI-based) method of identification of mycobacteria. We prepared a training dataset of over 260,000 positive and over 700,000,000 negative patches annotated on scans of 510 whole slide images (WSI) of ZN-stained slides (110 positive and 400 negative). Several image augmentation techniques coupled with different custom computer vision architectures were used. WSIs automatic analysis was followed by a report indicating areas more likely to present mycobacteria. Our model performs AI-based diagnosis (the final decision of the diagnosis of WSI belongs to the pathologist). The results were validated internally on a dataset of 286,000 patches and tested in pathology laboratory settings on 60 ZN slides (23 positive and 37 negative). We compared the pathologists' results obtained by separately evaluating slides and WSIs with the results given by a pathologist aided by automatic analysis of WSIs. Our architecture showed 0.977 area under the receiver operating characteristic curve. The clinical test presented 98.33% accuracy, 95.65% sensitivity, and 100% specificity for the AI-assisted method, outperforming any other AI-based proposed methods for AFB detection.

Role of immunohistochemistry in the diagnosis and staging of cutaneous squamous-cell carcinomas (Review).

Non-melanoma skin cancer (NMSC) is the most common type of neoplasm affecting Caucasian individuals, with squamous-cell carcinoma (cSCC) being the second most common type of NMSC after basal-cell carcinoma. The immunohistochemical study of cSCC is of particular importance, especially for the diagnosis of its rare forms, for which accurate and early diagnosis is crucial for survival. In the present review of the literature, the potentially significant value of immunohistochemical markers were highlighted to more accurately assess the biological behaviour, the prognosis of cSCC and to optimize case management. The immunohistochemical markers were classified from a pathophysiological point of view in order to present the mechanism by which carcinogenesis occurs with its subsequent evolution and therefore, to develop a more accurate novel risk staging criteria for this type of neoplasm.

Coexistence of Trisomy 8 and 13 in a Newly Diagnosed Patient With Diffuse Large B Cell Non-Hodgkin Lymphoma and Acute Myeloid Leukemia Secondary to Primary Myelofibrosis.

Concomitant diagnosis of non-Hodgkin lymphoma (NHL) and acute myeloid leukemia secondary to chronic myeloproliferative neoplasms (MPNs) is rarely reported. Patients with MPNs may have a second neoplasm, and the risk of lymphoid line neoplasms is 2.5-3.5 times for lymphoid line neoplasms. The explanation for this association is the genetic instability of hematopoietic progenitors in MPNs. An 80-year-old Caucasian man, with many comorbidities, presents for physical asthenia, sweating. The right inguinal adenopathy was known one month before the examination. The patient was diagnosed concomitantly with diffuse large B cell lymphoma (DLBCL) and acute myeloid leukemia (AML) secondary to primary myelofibrosis (PMF) and presented trisomy 8, trisomy 13, and triple-negative PMF status. The patient initially received two well-tolerated R mini CHOP series. This type of treatment was selected to treat DLBCL for one unfit patient for intensive chemotherapy due to his age and comorbidities. R mini CHOP administration was followed by severe aplasia that lasted approximately two weeks followed by severe thrombocytosis that reached 4000 x109/L, and Thromboreductin recommendation was mandatory. The result of the treatment was a partial response but with severe adverse events like neutropenia G4, due to the delay of the treatment the patient lost the response. It was mandatory to select another treatment line and the chosen was venetoclax; it was selected for the simultaneous treatment of DLBCL and the underlying AML. It was obtained a significant reduction in the size of the inguinal lymph node block in two weeks of treatment. Severe neutropenia was diagnosed and complicated with sepsis. The evolution is unfavorable with the installation of multiple organ dysfunction. The presence of a complex karyotype (trisomy 8, trisomy 13) in a patient with myeloid metaplasia with triple-negative PMF was associated with blast transformation and severe thrombocytosis. The patient was diagnosed concomitantly with DLBCL, making the therapeutic decision difficult. Venetoclax has been shown to be useful in the treatment of DLBCL but has been associated with severe neutropenia, which has led to infectious complications.

Characteristics and outcomes of patients with COVID-19 and liver injury: a retrospective analysis and a multicenter experience.

Background and aims. Patients with COVID-19 frequently present abnormal elevated liver function tests of unknown clinical significance. We aimed to investigate the characteristics and factors influencing outcome in patients with confirmed SARS-CoV-2 infection and liver injury on admission.Methods. This is a retrospective observational study of patients hospitalized in two COVID units in Romania. Relevant data on clinical and laboratory parameters and medication administered during the admission were analyzed to identify predictors of a negative outcome. Patients with confirmed COVID-19 and liver function tests (LFTs) above the upper limit of normal were included in the analysis.Results. From 1,207 patients, we identified 134 patients (11%) with abnormal LFTs during hospitalization. The majority of patients had mildly elevated levels and a predominantly cholestatic pattern of liver injury. Patients who received lopinavir/ritonavir were more likely to have increased ALAT levels (p<0.0001). Sixteen patients had pre-existing chronic liver disease, and they were more likely to suffer from severe COVID-19 (p=0.009) and have a negative outcome (p<0.001), but on multivariate analysis, only the severity of COVID-19 was predictive of death (OR 69.9; 95% CI 6.4-761.4).Conclusions. Mild liver injury is relatively common in COVID-19 and possibly influenced by medication. Patients with chronic liver disease are at high risk for negative outcome, but the severity of the infection is the only predictor of death.

Prognostic Potential of Tumor-Infiltrating Immune Cells in Resectable Oral Squamous Cell Carcinoma.

(1) Background: The immune microenvironment plays an important role in carcinogenesis and has prognostic potential in many types of cancer. In this study we assess the prognostic character of tumor-infiltrating immune cells CD4+, CD8+ and CD56+ in resectable oral squamous cell carcinoma (OSCC); (2) Methods: We have evaluated the densities of CD4+, CD8+ and CD56+ in two distinct compartments, intratumor and invasion front, in 90 patients with OSCC; (3) Results: Significant differences were found between the tumor compartments for the CD4+ and CD8+ lymphocytes. An improved outcome (OS) was seen in patients with high densities of intratumor CD8+ lymphocytes (p = 0.0086), CD8+ lymphocytes at the front of invasion (p = 0.0011) and for intratumor CD56+ cells (p = 0.0016). Multivariate analysis confirmed the independent prognostic role of CD8+ at the front of invasion (OR = 3.75, CI95% 1.17-12.35, p = 0.026) and for intratumor CD56+ cells (OR = 3.669, CI95% 1.09-15.37, p = 0.035); (4) Conclusions: Tumor-infiltrating CD8+ lymphocytes at the front of invasion and CD56+ in the intratumor compartment display predictive traits in OSCC. A reach immune infiltration with these types of cells is associated with an improved patient outcome.

COVID­19 vaccination and IgG and IgA antibody dynamics in healthcare workers.

Given the current outbreak of coronavirus disease 2019 (COVID­19) and the development and implementation of mass vaccination, data are being obtained by analyzing vaccination campaigns. In the present study, 69 healthcare workers who were exposed to patients with severe acute respiratory syndrome coronavirus­2 were monitored for specific immunoglobulin (Ig)G and IgA levels at different time periods. Prior to vaccination, after the first round of vaccination at 21 days (when the second dose of vaccine was administrated) and 24 days after the second round of vaccination, with an mRNA­based vaccine. The basal IgG and IgA levels in previously infected subjects and non­infected subjects notably differed. Vaccination increased the IgG and IgA levels after the first dose in most subjects from both groups, the levels of which further increased following the second round of vaccination. The associations between IgG and IgA levels following the first and second rounds of vaccination demonstrated that in the entire vaccination group, regardless of prior exposure to the infectious agent, the increment and levels of IgG and IgA were similar. Thus, the levels upon vaccination were statistically similar irrespective of the starting base line prior to vaccination. In the present study, seroconversion was achieved in all subjects following the second round of vaccination, with similar antibodies levels.

MLH1, BRAF and p53 - searching for significant markers to predict evolution towards adenocarcinoma in colonic sessile serrated lesions.

BACKGROUND AND AIM: Colonic serrated lesions are premalignant lesions, using an alternative malignization pathway, including multiple genetic and epigenetic alterations, as: mismatch repair deficiency due to MutL homolog 1 (MLH1) promoter methylation, tumor protein p53 (TP53) mutations, activating mutations of v-Raf murine sarcoma viral oncogene homolog B (BRAF) and Kirsten rat sarcoma viral oncogene homolog (KRAS). Our study aims to evaluate MLH1, BRAF and p53 immunohistochemical (IHC) status in sessile serrated lesions (SSLs), with and without dysplasia. MATERIALS AND METHODS: This is a retrospective case-control study including 20 SSLs with dysplasia and 20 SSLs without dysplasia (matching sex and age). IHC expression of MLH1, BRAF and p53 was evaluated as the percent of nuclear loss of MLH1, cytoplasmic positivity of BRAF and nuclear positivity of p53. Data concerning age, sex, localization of the lesion, dysplasia and IHC results were statistically processed using Microsoft Excel. RESULTS: We had very polymorphous patterns of IHC expression for BRAF, MLH1 and p53, especially in the dysplastic group. Thus, two patients were BRAF+∕MLH1-∕p53+, three were BRAF+∕MLH1-∕p53-, one was BRAF+∕MLH1+∕p53- and six were BRAF+∕MLH1+∕p53+. Dysplastic lesions without BRAF mutation exhibited the following phenotype: one case BRAF-∕MLH1-∕p53+, four BRAF-∕MLH1-∕p53- and three BRAF-∕MLH1+∕p53+. In the control group (SSLs without dysplasia), there was a more homogenous distribution of cases: eight cases BRAF+∕MLH1+∕p53-, seven BRAF-∕MLH1+∕p53-, one BRAF-∕MLH1-∕p53+, two BRAF-∕MLH1-∕p53- and two BRAF-∕MLH1+∕p53+. CONCLUSIONS: There are more routes on the serrated pathway, with different mutations and time of acquisition of each genetic or epigenetic lesion with the same morphological result. These lesions should be stratified according to their risk to poor outcome and their need to further surveillance.

The differential diagnosis of ulcerative colitis versus angiodysplasia of the colon with ischemic colitis.

Ulcerative colitis and Crohn's disease are the inflammatory bowel diseases with a continuously increasing of prevalence. Their exact causes are still not well known and, more than that, they are raising up serious issues of diagnosis. The same difficulties of diagnosis are encountered in the case of the colonic angiodysplasia or ischemic colitis (IC). Colonic angiodysplasia is a common vascular abnormality of the gastrointestinal tract, being diagnosed mostly in the elderly persons, in a similar manner to the IC. For all these diseases comorbidities plays their important role both as causes of the onset and aggravating factors during the evolution. The differential diagnosis between these three conditions needs a complex and multidisciplinary approach, involving at least clinical evaluation, endoscopic and imaging assessments, and histopathological exam.

E-cadherin and aquaporin 1 co-expression analysis in hepatocellular carcinoma: a pilot study.

Hepatocellular carcinoma (HCC) is the main primary liver malignancy, being associated with both health and economic burden worldwide. Recently, novel molecular markers and possible therapeutic targets were identified. Different adhesion molecules, as well as possible angiogenesis-associated targets can be prime candidates when investigating novel therapies. Considering these premises, our goal was to study the co-existence of E-cadherin and aquaporin 1 (AQP1) in a series of HCC diagnosed patients. Utilizing archived tissue fragments from 17 patients diagnosed with well-to-moderate and poorly differentiated HCC, as well as four samples of normal liver tissue and using a highly specific biotin-free tyramide amplification technique, we have assessed here the expression of E-cadherin and AQP1 during HCC carcinogenesis. Moreover, as we have observed that some of the AQP1 expression seems membrane-bound, we have sought to evaluate their co-localization. Our data showed, as expected, that E-cadherin decreases from control tissue to low-grade and respectively, high-grade HCC. AQP1 was expressed, also as already known, at the level of endothelial blood vessels and bile ducts epithelia, however, we have showed here for the first time that this water pore is also expressed in the cytoplasm and membranes of hepatocytes, both in control and HCC tissue. Moreover, AQP1 expression parallels the decrease of E-cadherin expression during carcinogenesis, but together with this downregulation, we have also found a spatial decrease in the colocalization of the two proteins. Altogether, utilizing a biotin-free tyramide signal amplification technique, this study shows for the first time that AQP1 is expressed at the level of liver epithelia, in both control and HCC tissue.

FOXP3 in Melanoma with Regression: Between Tumoral Expression and Regulatory T Cell Upregulation.

Cutaneous melanoma is a significant immunogenic tumoral model, the most frequently described immune phenomenon being tumor regression, as a result of the interaction of tumoral antigens and stromal microenvironment. We present a retrospective cohort study including 52 cases of melanoma with regression. There were evaluated correlations of the most important prognostic factors (Breslow depth and mitotic index) with FOXP3 expression in tumor cells and with the presence of regulatory T cells and dendritic cells in the tumoral stroma. FOXP3 expression in tumor cells seems an independent factor of poor prognosis in melanoma, while regression areas are characterized by a high number of dendritic cells and a low number of regulatory T cells. FOXP3 is probably a useful therapeutical target in melanoma, since inhibition of FOXP3-positive tumor clones and of regulatory T cells could eliminate the ability of tumor cells to escape the immune defense of the host.

Pyoderma gangrenosum and suppurative hidradenitis association, overlap or spectrum of the same disease? Case report and discussion.

Suppurative hidradenitis and pyoderma gangrenosum are rare disorders that can be seen isolated or even more rare, as part of different autoinflammatory syndromes: Pyoderma gangrenosum, acne, and hidradenitis suppurativa (PASH), pyoderma gangrenosum, acne, pyogenic arthritis, and hidradenitis suppurativa (PAPASH) or psoriatic arthritis, pyoderma gangrenosum, acne, and hidradenitis suppurativa (PsAPASH). Although they have different clinical features, suppurative hidradenitis and pyoderma gangrenosum seem to share similar pathogenic pathways involving a dysregulated innate immune system, with neutrophilic inflammation, mediated by IL-1ß, controlled by NALP3 inflammasome pathway. We report a case of a 53-year-old male patient previously diagnosed with HS in inguinal-scrotal area that developed rapidly after a traumatic injury on his left anterior calf, a painful inflammatory plaque with pustules on the surface that rapidly progressed (24-48 h) to form ulcers. The lesions ended up healing with a large scarring plaque with cribriform openings, multiple fibrous bridges, open comedones, and double-ended pseudo-comedones. Although the clinical aspect at presentation together with the aspect on the first biopsy were suggestive for pyoderma gangrenosum, the healing aspect is more commonly seen in suppurative hidradenitis. Commonly seen in acne, in the healing phase of suppurative hidradenitis but more rarely in pyoderma gangrenosum, the formation of comedones seem to be a complex process and raise the question if these entities represent in our patient an association, an overlap or the spectrum of the same disease.

Bacillary angiomatosis triggered by severe trauma in a healthy Caucasian patient: A case report.

Bacillary angiomatosis represents a cutaneous and systemic infection caused by Bartonella species, typically described in the past in HIV-positive patients or associated with immunodeficiencies. More recent case reports had brought into attention the probability that this entity may manifest in otherwise healthy individuals, triggered by trauma and skin burns. The physiopathology of this neoproliferative process is based on the production of angiogenetic molecules, such as vascular endothelial growth factor (VEGF) and IL-8. In case of an inadequate treatment, the evolution can be fatal, with a systemic dissemination of the abscesses within the gastro-intestinal tract, respiratory tract, brain and bones. The appropriate therapy is with oral erythromycin and doxycycline, but several treatments such as cephalosporins, penicillins, macrolides, aminoglycosides, rifampin, dapsone, ciprofloxacin, have been tried with favorable results. Herein we present the case of a Caucasian patient, seronegative for HIV, who developed multiple vascular papules and nodules on the face, after a severe trauma and which healed after an adequate antibiotic therapy with oral clarithromycin.

Efficacy of methotrexate as anti-inflammatory and anti-proliferative drug in dermatology: Three case reports.

Methotrexate (MTX) is a folic acid analog with anti-proliferative (anti-neoplastic, cytotoxic), immunosuppressive and anti-inflammatory properties, which has been used in the treatment of various cutaneous disorders, such as psoriasis, keratoacanthoma, pityriasis rubra pilaris, atopic dermatitis, mycosis fungoides, bullous skin diseases, systemic sclerosis, morphea, lupus erythematosus, dermatomyositis and crusted scabies. Inhibition of cell proliferation is explained through its role in blocking DNA/RNA synthesis, by inhibiting dihydrofolate reductase, necessary for the production of pyrimidine and purine nucleotides. An anticancer effect can be related to α-oxoaldehyde metabolism (MTX increases methylglyoxal levels). Its anti-inflammatory property is based on the inhibition of 5-aminoimidazole-4-carboxamide ribonucleotide transformylase, thus increasing intracellular and extracellular adenosine, a purine nucleoside with anti-inflammatory effect. This drug can limit inflammation by scavenging free radicals and decreasing malondialdehyde-acetaldehyde protein-adduct production. Moreover, the anti-proliferative and anti-inflammatory effects can also be related to inhibition of the DNA methylation pathway, thus inhibiting methionine formation. The aim of the present study was to report various dermatological cases from our daily practice that demonstrate the efficacy of MTX in the treatment of cutaneous diseases, highlighting different mechanisms of action: its anti-inflammatory effect in psoriasis and its anti-proliferative, and anti-neoplastic effect in well-differentiated squamous cell carcinoma or in keratoacanthoma. Moreover, different administration pathways and doses are addressed. Assessment of the treatment plan, clinical improvement of cutaneous lesions, biologic evaluation, final aesthetic result, quality of life, as well as potential adverse effects and drug tolerance related to each case mentioned.

Dendritic cell distribution in mycosis fungoides vs. inflammatory dermatosis and other T-cell skin lymphoma.

Dendritic cells (DCs) are antigen-presenting cells with an important role in the innate and adaptive immune system. In skin lesions, cutaneous DCs (Langerhans cells, dermal DCs and plasmacytoid DCs) are involved in immune activation in inflammatory benign lesions, as well as in malignant lymphoid proliferations. Density and distribution of DCs in the dermal infiltrate can be helpful to differentiate benign, reactive infiltrate from malignant nature of the lymphoid population. We performed a retrospective study including 149 patients: 35 with mycosis fungoides, 35 with spongiotic dermatitis, 35 with psoriasis, 35 with lupus and 9 with cutaneous T-cell lymphomas (other than mycosis fungoides), diagnosed using histopathological and immunohistochemical stains. Density and distribution of DCs were evaluated using specific markers (CD1a, CD11c and langerin). In all cases, numerous DCs were identified in the dermal infiltrate. Their number was significantly increased in mycosis fungoides and T-cell lymphomas and moderately increased in inflammatory lesions. Variable patterns of distribution were identified such as clusters of DCs with arachnoid extension in mycosis fungoides, nodular pattern in inflammatory lesions and dispersed distribution with peripheric accumulation in T-skin lymphomas. Therefore, immunohistochemical characterization of DC distribution can be an adjuvant tool in differential diagnosis in inflammatory dermatosis and skin lymphomas.