Diagnostic interobserver variability in Crohn's disease- and ulcerative colitis-associated dysplasia: a multicenter digital survey from the IG-IBD Pathologists Group.

BACKGROUND: Crohn's disease (CD) and ulcerative colitis, two forms of inflammatory bowel disease (IBD), are chronic and relapsing conditions of the gastrointestinal tract both characterized by long lasting chronic inflammation and increased risk of dysplasia and colorectal cancer (CRC). The aim of our study was to evaluate the interobserver agreement about IBD-associated dysplasia among pathologists belonging to the Italian Group for Inflammatory Bowel Diseases (IG-IBD P). METHODS: The present multicenter survey was performed using telepathology, supported by an open source E-learning platform. Biopsy specimens from 30 colonoscopies and from 20 patients were included. The glass slides of any case, including clinical and endoscopic data, were digitalized and uploaded on the E-learning platform. All the digital slides were grouped in 54 diagnostic "blocks". Blinded histopathological evaluation on all the digital slides was performed by 20 gastrointestinal pathologists. Closed-ended questions about (1) the occurrence of IBD; (2) the classification of IBD (as UC or CD); (3) the presence of active versus quiescent disease; (4) the presence of dysplasia; (5) the possible association of dysplasia with the sites of disease (dysplasia-associated lesion or mass-DALM vs adenoma-like mass-ALM); (6) the grading of dysplasia according to the ECCO guidelines (negative, indefinite, low grade, high grade categories) and (7) the presence of associated serrated features, were proposed in each case. Inter-observer agreement was evaluated by mean agreement percentage and kappa statistic, when suitable. RESULTS: The diagnosis of IBD was confirmed in 19 of 20 patients, 17 of 19 being classified as UC, 2 as CD. The mean interobserver agreement percentages about (1) the evidence of IBD, (2) the presence of either UC or CD and (3) the activity grading resulted to be 80%, 69% and 86%, respectively. Dysplasia was detected in 8/20 patients, with moderate agreement between pathologists (mean 72%, k 0.48). Particularly, low grade dysplasia was found in 13 biopsies (combined k 0.38), whereas high grade dysplasia in 8 (combined k 0.47). When the endoscopic and histopathological data were combined, features consistent with DALM were found in 6 of 20 patients with low grade dysplasia and those consistent with ALM in 2 patients with low grade dysplasia in a single biopsy (mean agreement: 86%). An associated serrated pattern was discovered in 4 patients (7 biopsies). CONCLUSIONS: Our study showed moderate interobserver agreement about the histopathological detection and classification of IBD-associated dysplasia. Further efforts should be undertaken to integrate the histopathological data with both the ancillary tests and molecular investigations.

Nodular skin lesions: correlation of reflectance confocal microscopy and optical coherence tomography features.

BACKGROUND: Nodular lesions have common clinical appearance but different prognoses. Differential diagnosis between melanoma (MM), basal cell carcinoma (BCC) and dermal naevus (DN) poses a challenge in clinical practice. Reflectance confocal microscopy (RCM) and optical coherence tomography (OCT) are promising non-invasive imaging techniques, potentially able to decrease redundant biopsies. RCM allows in vivo visualization of skin down to the papillary dermis at almost histological resolution, while OCT, particularly dynamic OCT (D-OCT), provides images deeper within the dermis and reveals the vascular pattern. OBJECTIVES: To identify correlating features observed with RCM and OCT associated with the different nodular lesion diagnoses. METHODS: We retrospectively assessed 68 nodular lesions (30 MM, 20 BCC and 18 DN) with RCM and subsequently OCT. At the end of the study, evaluations were matched with histopathological diagnosis and statistical analysis was performed. RESULTS: In MM, 57% (17/30) evidenced both cerebriform nests at RCM and icicle-shaped structures at OCT, with higher average Breslow index. In 80% of BCCs with basaloid islands at RCM, OCT showed ovoid structures. More than half of DN (56%) showed hyporeflective nests at OCT and either dense nests or dense and sparse nests at RCM. CONCLUSIONS: The combined use of RCM and OCT offers a better understanding of the morphological architecture of nodular lesions, correlating RCM parameters with OCT and vice versa, assisting in turn with early differential diagnosis of malignant and benign nodular lesions. The correlation between icicle-shaped structures and cerebriform nests in MM and their association with Breslow index requires future research.

Development of a Desmocollin-3 Active Mouse Model Recapitulating Human Atypical Pemphigus.

Pemphigus vulgaris (PV) is a life-threatening mucocutaneous autoimmune blistering disease. It is often associated with autoantibodies to the desmosomal adhesion proteins Desmoglein 3 (DSG3) and Desmoglein 1 (DSG1). Recently, auto-antigens, such as desmocollins and others have been described in PV and in atypical pemphigus forms such as Pemphigus Herpetiformis (PH), Pemphigus Vegetans (PVeg), and Paraneoplastic Pemphigus (PP). Desmocollins belong to a cadherin subfamily that provides structure to the desmosomes and play an important role in cell-to-cell adhesion. In order to verify the pathogenic activity of anti-Desmocollin 3 (DSC3) antibodies, we developed an active disease model of pemphigus expressing anti-DSC3 autoantibodies or anti-DSC3 and anti-DSG3 antibodies. This approach included the adoptive transfer of DSC3 and/or DSG3 lymphocytes to Rag2-/- immunodeficient mice that express DSC3 and DSG3. Our results show that the presence of anti-DSC3 auto-antibodies is sufficient to determine the appearance of a pathological phenotype relatable to pemphigus, but with features not completely super-imposable to those observed in the DSG3 active model, suggesting that the DSC3 active model might mimic the atypical pemphigus. Moreover, the presence of both anti-DSC3 and anti-DSG3 antibodies determines a more severe phenotype and a slower response to prednisolone. In conclusion, we have developed an adult DSC3 pemphigus mouse model that differs from the DSG3 model and supports the concept that antigens other than desmogleins may be responsible for different phenotypes in human pemphigus.

Morphological classification of melanoma metastasis with reflectance confocal microscopy.

BACKGROUND: Cutaneous malignant melanoma metastases differential diagnosis is challenging, as clinical and dermoscopic features can simulate primary melanoma or other benign or malignant skin neoplasms, and in-vivo reflectance confocal microscopy could assist. Our aim was to identify specific reflectance confocal microscopy features for cutaneous malignant melanoma metastases, and epidermal and dermal involvement. METHODS: A retrospective, multicentre observational study of lesions with proven cutaneous malignant melanoma metastases diagnosis between January 2005 and December 2016. Lesions were retrospectively assessed according to morphological features observed at reflectance confocal microscopy. Potential homogeneous subgroups of epidermal or dermal involvement were investigated with cluster analysis. RESULTS: Cutaneous malignant melanoma metastases (51 lesions in 29 patients) exhibited different frequencies of features according to metastasis dermoscopy patterns. Lesions classified at dermoscopy with nevus-like globular and non-globular patterns were more likely to be epidermotropic, showing characteristics of epidermal and dermal involvement at reflectance confocal microscopy. Other dermoscopy pattern classifications were more likely to be dermotropic, showing characteristics od dermal involvement at reflectance confocal microscopy. Distinguishing features at reflectance confocal microscopy included irregular (78%) and altered (63%) epidermis, pagetoid infiltration (51%), disarranged junctional architecture (63%), non-edged papillae (76%), dense and sparse, and cerebriform nests in the upper dermis (74%), and vascularity (51%). Cluster analysis identified three groups, which were retrospectively correlated with histopathological diagnoses of dermotropic and epidermotropic diagnoses (P < 0.001). The third cluster represents lesions with deep dermis morphological changes, which were too deep for evaluation with reflectance confocal microscopy. CONCLUSIONS: Specific reflectance confocal microscopy features of cutaneous malignant melanoma metastases for correct diagnosis, and subtype diagnosis, seem achievable in most cases where morphological alterations are located above the deep dermis.

Optimal processing of ESD specimens to avoid pathological artifacts.

BACKGROUND: En bloc endoscopic submucosal dissection (ESD) has been recently introduced as a treatment for precancerous/neoplastic gastrointestinal conditions. The aim of the present study was histological assessment of en bloc ESD specimens. METHODS: Fifty-three ESD specimens were positioned over a cellulose acetate support (40 specimens; 12 from the upper gastrointestinal tract and 28 from the lower gastrointestinal tract) or pinned with nails on polystyrene or cork (13 specimens; 7 from the upper gastrointestinal tract and 6 from the lower gastrointestinal tract). We cut consecutive 2 mm-thick sections stained with hematoxylin and eosin. From the first and the last sections, we obtained a second slide, after a 180° rotation and re-embedding. The quality of ESD samples was scored as inadequate, suboptimal and adequate, based on the amount of crushing, shearing and stretching artifacts that were scored from 0 (absent) to 2 (diffuse or maximum). From the sum of these we obtained a global artifact score (GAS). RESULTS: Removed lesions were: adenocarcinoma (5 cases), neuroendocrine tumor (NET) G1 (1 case), premalignant conditions, including adenomatous polyps (41 cases) and hyperplastic lesions (6 cases). A positive deep surgical margin was found in 8/53 cases (15%): high- and low-grade dysplastic glands were detected in 5 cases, low-grade adenocarcinoma in 2, and NET cells in 1. Dysplastic glands were detected in the lateral surgical margins of 12 ESD specimens (23%). Among the ESD specimens positioned on the cellulose acetate support, apart from the modifications due to electrocoagulation, 2 (5%) showed shearing modifications. In the group of ESD specimens fixed with nails, 5 (38%) showed shearing, 10 (77%) crushing artifacts, 11 (85%) stretching and 11 (85%) multiple holes caused by the nails. On the basis of these data all histological specimens from ESD on cellulose acetate were adequate (GAS 0-1).However, in the group of ESD fixed with nails, 1 was adequate (GAS 0), 11 suboptimal (GAS 2-5) and 1 inadequate (GAS 6). CONCLUSIONS: Specific devices including cellulose support and adequate sampling blocks can be helpful to perform accurate histological assessment of ESD specimens after en bloc ESD for precancerous/neoplastic gastrointestinal lesions, with complete analysis of the status of the margins and the entirely en bloc evaluation of the lesion.

Reinterpreting dermoscopic pigment network with reflectance confocal microscopy for identification of melanoma-specific features.

BACKGROUND: Pigment network is an important dermoscopic feature for melanocytic lesions, but alterations in grid line thickness are also observed in melanomas. OBJECTIVE: To investigate features of thick, thin and mixed pigment networks at dermoscopy and their respective features at reflectance confocal microscopy (RCM) for differential diagnosis, correlated with histology. METHODS: All melanocytic lesions with histological diagnosis, evaluated between January 2010 and May 2014, were enrolled and classified according to dermoscopy evaluation of the pigment networks: thin, thick and mixed. RESULTS: Thin network in melanoma was characterized by a honeycombed pattern (P < 0.001), dendritic cells (P < 0.001), atypical ringed pattern (P = 0.035) and structureless area (P = 0.012), whereas round cells (P < 0.001), dendritic cells (P < 0.001) and atypical meshwork pattern (<0.001) characterized thick network in melanoma. Mixed network type in melanoma shared honeycombed (P = 0.049) and typical ringed patterns (P = 0.045) in the thin area and round cells (P < 0.001) and atypical meshwork pattern (P < 0.001) in the thick area. Thin network in nevi was characterized by cobblestone (P < 0.001) and typical ringed patterns (P = 0.035), whereas thick network in nevi showed a typical meshwork pattern (P < 0.001). Mixed nevi shared the same features and patterns, but more frequently with inflammatory infiltrate (P = 0.047). CONCLUSION: Differential diagnosis between melanocytic lesions (nevi or melanoma) in thin, thick and mixed pigment networks observed at dermoscopy can be assisted by RCM to improve diagnostic accuracy.

Double heterozygosity for BRCA1 and hMLH1 gene mutations in a 46-year-old woman with five primary tumors.

Germline mutations in BRCA1 and BRCA2 genes predispose to hereditary breast cancer, whereas carriers of mutations in any of the mismatch repair genes (MMR; hMLH1, hMSH2, hMSH6, hPMS2) are highly susceptible to Lynch syndrome. In the present study, we describe a woman affected by unilateral breast cancer at the age of 35 years. After 4 years, during the follow-up she developed synchronous (and asymptomatic) endometrial cancer, ovarian carcinoma and renal clear cell carcinoma. After 7 years (at age 46), the patient developed an infiltrating carcinoma of the contralateral breast and died in a few months of metastatic disease. Initial investigations led to the detection of a constitutional mutation in the BRCA1 gene. The extended genealogical tree disclosed a suspected history of colorectal carcinoma in the maternal branch. Endometrial cancer of the proband was investigated for microsatellite instability (MSI) and immunohistochemical expression of MLH1, MSH2 and MSH6 proteins. An high MSI status and lack of expression of MLH1 protein were detected. hMLH1 gene sequencing revealed the presence of a constitutional mutation, which was also found in the mother of the proband. Loss of the wild-type hMLH1 allele was detected in both breast tumors, thus suggesting that the MMR defect contributed to the development of the breast cancer.

Sodium/iodide symporter is expressed in the majority of seminomas and embryonal testicular carcinomas.

Testicular cancer is the most frequent cancer in young men. The large majority of patients have a good prognosis, but in a small group of tumors, the current treatments are not effective. Radioiodine is routinely used in the treatment of thyroid cancer and is currently investigated as a potential therapeutic tool even for extra-thyroid tumors able to concentrate this radioisotope. Expression of Na(+)/I(-) symporter (NIS (SLC5A5)), the glycoprotein responsible for iodide transport, has been demonstrated in normal testicular tissue. In this study, we analyzed NIS expression in a large series of testicular carcinomas. Our retrospective series included 107 patients operated for testicular tumors: 98 typical seminomas, six embryonal carcinomas, one mixed embryonal choriocarcinoma, and two Leydig cells tumors. Expression and regulation of NIS mRNA and protein levels were also investigated in human embryonal testicular carcinoma cells (NTERA) by real-time RT-PCR and western blotting respectively. Immunohistochemical analysis showed the presence of NIS in the large majority of seminomas (90/98) and embryonal carcinomas (5/7) of the testis but not in Leydig cell carcinomas. Expression of NIS protein was significantly associated with lymphovascular invasion. In NTERA cells treated with the histone deacetylase inhibitors SAHA and valproic acid, a significant increase in NIS mRNA (about 60- and 30-fold vs control, P<0.001 and P<0.01 respectively) and protein levels, resulting in enhanced ability to uptake radioiodine, was observed. Finally, NIS expression in testicular tumors with the more aggressive behavior is of interest for the potential use of targeting NIS to deliver radioiodine in malignant cells.

Morphological analysis of three extrathoracic bronchogenic cysts simulating neoplasms.

Bronchogenic cyst is a congenital anomaly of the primitive foregut. Unusual occurrences in extrathoracic sites have been described in the literature, some of which may clinically simulate neoplasms. We report three additional cases arising near the left adrenal gland, left ovary and gastric wall. Pathological findings are discussed, together with a review of the literature.

Lymphatic vessel density and its prognostic value in stage I colorectal carcinoma.

AIMS: The assessment of lymphatic vessel density (LVD) has been suggested as a tool to determine the metastatic risk of neoplasias. On this premise, the authors aimed to verify whether progression risk of stage I colorectal cancer may be related to LVD. The authors also evaluated and correlated vascular endothelial growth factor (VEGF)-A expression with LVD revealed in the same cases in order to investigate its potential lymphangiogenic role in the early stage colorectal cancer. METHODS: LVD and VEGF immunoexpression were analysed and compared in series of 29 stage I surgically resected colorectal carcinomas obtained from patients showing disease progression and in a cohort of 23 stage I colorectal cancers from patients with no evidence of disease progression. The prognostic value of LVD and of VEGF expression on the progression-free survival to colorectal cancer was investigated. RESULTS: A high density of peritumoural lymphatics (P-LVD) was significantly associated with high VEGF expression and disease progression. Moreover, high P-LVD and high VEGF expression were significant negative prognostic parameters associated with a shorter disease-free interval in stage I colorectal cancer. CONCLUSIONS: If our findings are further confirmed in other studies, the assessment of P-LVD on surgical specimens might be used as a tool to identify patients with stage I colorectal cancer at higher risk of progression in order to submit them to adjuvant therapies. Since P-LVD seems to show a VEGF-A mediated regulation in stage I colorectal cancer, therapies targeting this factor might be exploited to reduce lymphangiogenesis and the progression risk of this neoplasia.

Well-differentiated giant scrotal liposarcoma: case presentation and management.

Scrotal liposarcoma is an uncommon disease, usually found after the fifth decade. We describe the case of a well-differentiated scrotal liposarcoma associated with a considerable inflammatory reaction, treated with surgical ablation.