The effect of the electromagnetic field on metabolic-active bacterial biofilm experimentallyinduced on titanium dental implants.

Microbial biofilm is of paramount importance in the development of mucositis or peri-implantitis in patients with dental implants. This study was designed to investigate whether an electromagnetic field at high frequency waves directly applied on 33 titanium implants could remove experimentally-induced Enterococcus faecalis bacterial biofilm. A specially designed device (X-IMPLANT) was used to generate the electromagnetic field, with output power of 8 W, supply frequency (action/pause) 3/2s, and an output frequency of 625±5% kHz in plastic devices containing the biofilm-covered implants immersed in sterile saline. The bacterial biofilm on both treated and untreated control implants was quantitatively measured by phenol red-based Bio-Timer-Assay reagent. The kinetic analysis of the curves showed that the electrical treatment generated by the X-IMPLANT device completely removed the bacterial biofilm after 30 minutes of treatment (p<0.01). Elimination of the biofilm was also confirmed by chromatic observation in the macro-method. Our data seem to indicate that the procedure could be considered for clinical application in peri-implantitis to counteract bacterial biofilm on dental implants.

Disinfection of Root Canals with Laser-Activated Irrigation, Photoactivated Disinfection, and Combined Laser Techniques: An Ex Vivo Preliminary Study.

Objective: This study aimed to evaluate the efficacy of laser-activated irrigation using photon-induced photoacoustic streaming (PIPS®) and photoactivated disinfection (PAD) techniques and their combination to improve penetration and activation of toluidine blue in the endodontic space of teeth experimentally infected with Enterococcus faecalis. Materials and methods: Twenty-seven extracted single-root teeth were instrumented, sterilized, and infected with E. faecalis and divided into seven groups of three teeth each: Group A [sodium hypochlorite (NaClO) 5% hand irrigation], Group B [NaClO 5% hand irrigation+ethylenediaminetetraacetic acid (EDTA)+NaClO 5% activated by PIPS], Group C (EDTA+NaClO 5% activated by PIPS), Group D (toluidine blue activated by PAD), Group E (toluidine blue activated by PIPS and PAD), Group F (NaClO 5% hand irrigation+toluidine blue activated by PAD), and Group G (NaClO 5% hand irrigation+toluidine blue activated by PIPS and PAD). Finally, positive and negative group controls were prepared. The presence of biofilms after the treatments was assessed by the BioTimer assay. PIPS was performed with an Er:YAG laser (2940 nm, LightWalker, Fotona® d.o.o., Slovenia) at 20 mJ, 15 Hz, 0.3 W, and 50-µs pulse duration. PAD was performed with a 635 nm diode laser (Smart M, Lasotronix®, Poland) at 400 mW in continuous wave (CW). Results: When NaClO was used, significant decontamination (p ≤ 0.05) was obtained in all experimental groups with respect to the positive control, other than Group G. Irrigation with EDTA+NaClO activated by PIPS produced a higher level of decontamination than Group A (p ≤ 0.05). Significant results in reducing biofilm load compared with the control and Group A were observed when NaClO was coupled with toluidine blue activated by PAD (p ≤ 0.05). Conclusions: Disinfection of root canals can be obtained using a combination of different irrigants, photosensitizers, and activation protocols. EDTA+NaClO using the PIPS protocol and toluidine blue activated by PAD (both preceded by NaClO irrigation) can be considered effective tools. The possibility of replacing NaClO with toluidine blue, whatever the method of activation, should be further investigated.

OLGA Gastritis Staging for the Prediction of Gastric Cancer Risk: A Long-term Follow-up Study of 7436 Patients.

OBJECTIVES: Gastritis OLGA-staging ranks the risk for gastric cancer (GC) in progressive stages (0-IV). This long-term follow-up study quantifies the GC risk associated with each OLGA stage. METHODS: Consecutive patients (7436) underwent esophagogastroscopy (T-0), with mapped gastric biopsies, OLGA staging, and H. pylori status assessment. Patients with neoplastic lesion (invasive or non-invasive) at the index endoscopy (and/or within 12 months) were excluded. All patients were followed-up (T-1) by combining different sources of clinical/pathological information (Regional Registries of: (i) esophagogastroduodenoscopies; (ii) pathology reports; (iii) cancer, (iv) mortality). The endpoint was histologically documented development of gastric epithelial neoplasia. RESULTS: At T-0, the patients' distribution by OLGA stage was: Stage 0 = 80.8%; Stage I = 12.6%; Stage II = 4.3%; Stage III = 2.0%; Stage IV = 0.3%; H. pylori infection was detected in 25.9% of patients. At the end of the follow-up (mean/median = 6.3/6.6 years), 28 incident neoplasia were documented (overall prevalence = 0.60 per 103/person-years; low-grade intraepithelial neoplasia = 17/28; high-grade intraepithelial neoplasia = 4/28; GC = 7/28). By OLGA stage at the enrollment, the rate of incident neoplasia was: Stage 0 = 1 case; rate/103 person-years = 0.03; 95%CI: 0.004-0.19; Stage I = 2 cases; rate/103 person-years = 0.34; 95%CI: 0.09-1.36; Stage II = 3 cases; rate/103 person-years = 1.48; 95%CI: 0.48-4.58; Stage III = 17 cases; rate/103 person-years = 19.1; 95%CI: 11.9-30.7; Stage IV = 5 cases; rate/103 person-years = 41.2; 95%CI: 17.2-99.3. Multivariate analysis including gender, age, H. pylori status, and OLGA stage at enrollment only disclosed OLGA stage as predictor of neoplastic progression (OLGA stage III: HR = 712.4, 95%CI = 92.543-5484.5; OLGA stage IV: HR = 1450.7, 95%CI = 166.7-12626.0). CONCLUSIONS: Among 7436 patients, OLGA stages at the enrollment correlated significantly with different risk for gastric neoplasia. Based on the obtained results, gastritis staging is a critical adjunct in endoscopy follow-up protocols aimed at GC secondary prevention.

Cortactin and phosphorylated cortactin tyr421 and tyr466 expression in supraglottic laryngeal carcinomas and lymph node metastases.

BACKGROUND: The most important adverse prognostic factor for laryngeal squamous cell carcinoma (LSCC) is the presence of cervical lymph node metastases. The supraglottic area of the larynx is richly supplied with lymphatics, and 25%-75% of supraglottic carcinomas metastasize in neck lymph nodes. Cortactin is a multidomain protein related to actin cytoskeleton regulation, podosome and lamellipodia formation, integrin signaling, axon guidance and extracellular matrix degradation. Cortactin is involved in metastasis formation because of its role in cell mobility. The present study focused mainly on the role of cortactin and phosphorylated cortactin (residues tyr421 and tyr466) expression and subcellular localization in primary supraglottic LSCCs and their cervical lymph node metastases. METHODS: The immunohistochemical expression of cortactin, p-Y466-cortactin and p-Y421-cortactin was assessed in 38 primary supraglottic LSCCs and 10 lymph node metastases. The statistical approach included bootstrapping analysis. RESULTS: Despite a significantly higher expression of cortactin in carcinoma cells than in adjacent normal laryngeal mucosa, no associations emerged between prognosis and the expression of cortactin or its isoforms in supraglottic LSCC. Statistical analysis found cortactin expression higher in less-differentiated LSCCs (p = 0.03). A significant direct correlation was found between cortactin and p-Y466-cortactin levels (p = 0.031), and between p-Y466-cortactin and p-Y421-cortactin levels (p = 0.001). CONCLUSIONS: Cortactin expression in carcinoma cells and its known involvement in the EGFR pathway suggest a role for this protein as a target for LSCC therapy. Further prospective studies are needed to investigate the potential of cortactin, p-Y466-cortactin and p-Y421-cortactin expression as markers of response to treatment (particularly EGFR-directed agents) in LSCC.

Adenosquamous gallbladder carcinoma: Multigene hotspot mutational profiling reveals a monoclonal origin of the two components.

Adenosquamous carcinoma (ASC) of the gallbladder is a rare malignant tumor that is characterized by a coexisting of glandular and squamous components. In a case of ASC, we performed hotspot multigene mutational profiling of 164 hotspot regions of eleven cancer-associated genes (AKT1, APC, BRAF, CTNNB1, KIT, KRAS, NRAS, PDGFRA, PIK3CA, PTEN and TP53) in the two microdissected components. Both tumor phenotypes resulted characterized by a p.E542K point mutation in the PIK3CA gene, whereas adenocarcinoma component revealed also a TP53 Q331* homozygous stop mutation. Of note, coexisting high-grade dysplastic epithelium was characterized by a mixed cell population, with an upper part featuring a glandular differentiation and a basal layer of p63 positive (squamous committed) cells. Overall these data provide evidence of an early squamous differentiation of the lesion with a common genetic landscape of the two components.

Pigmented trichoblastoma developed in a sebaceous nevus: HRAS mutation as a common molecular driver.

A 40-year-old woman presented with a pigmented nodule on a previously existing yellowish, verrucous plaque on the scalp. The histological diagnosis was consistent with a pigmented trichoblastoma developed within a sebaceous nevus (SN). A multigene hotspot mutational profiling of the BRAF, NRAS, HRAS and KRAS genes was carried out, and a shared G13R HRAS mutation in both the trichoblastoma and the sebaceous nevus components was found. These data support a common molecular landscape of the two lesions.

Cortactin and phosphorylated cortactin tyr466 expression in temporal bone carcinoma.

PURPOSE: Cortactin is a multidomain protein engaged in several cellular mechanisms involving actin assembly and cytoskeletal arrangement. Cortactin overexpression in several malignancies has been associated with increased cell migration, invasion, and metastatic potential. Cortactin needs to be activated by tyrosine or serine/threonine phosphorylation. The role of cortactin and phosphorylated cortactin (residue tyr466) was investigated in temporal bone squamous cell carcinoma (TBSCC). MATERIALS AND METHODS: Immunohistochemical expression of cortactin and phosphorylated cortactin (residue tyr466) was assessed in 27 consecutively-operated TBSCCs. RESULTS: Several clinicopathological variables correlated with recurrence (pT stage, dura mater involvement), and disease-free survival (DFS) (cT stage, pT stage, pN status, dura mater involvement). Twenty-three of 24 immunohistochemically evaluable TBSCCs were cortactin-positive. Median cortactin expression was 75.0%. Cortactin reaction in the cytoplasm was more intense in carcinoma cells than in normal adjacent tissue. Recurrence and DFS rates did not correlate with cortactin and phosphorylated cortactin (residue tyr466) expression in TBSCC specimens. CONCLUSIONS: Cortactin upregulation in TBSCC supports the conviction that inhibiting cortactin functions could have selective effects on this malignancy. Multi-institutional studies should further investigate the role of cortactin and phosphorylated cortactin in TBSCC, and their potential clinical application in integrated treatment modalities.

Relaxin-2 expression in oral squamous cell carcinoma.

BACKGROUND: When advanced, oral squamous cell carcinoma (OSCC) may involve adjacent non-epithelial structures, and the prognosis is worse for bone invasion. Human relaxin-2 is a peptide hormone that has recently been associated with cancer. It can induce human osteoclast differentiation and activation, suggesting a role in tumor-driven osteolysis. This study was a preliminary assessment of the prognostic role of relaxin-2 in surgical specimens of OSCC tissue and adjacent but uninvolved mandibular/maxillary bone. METHODS: Relaxin-2 immunohistochemical expression and reaction intensity were assessed in tumor and uninvolved adjacent mandibular/maxillary bone specimens from 23 operated OSCC patients. RESULTS: All OSCC specimens were positive for relaxin-2. The intensity of its reaction in OSCC correlated significantly with the pattern of the tumor's invasion front (p = 0.02), being higher with the infiltrative pattern. Mean relaxin-2 immunohistochemical expression was higher in patients whose OSCC recurred after treatment than those experiencing no recurrence (81.3% ± 22.6% vs. 59.5% ± 29.7%, respectively). A significant direct association emerged between relaxin-2 expression in OSCC specimens and recurrence rate (p = 0.049). CONCLUSIONS: Relaxin-2 expression in OSCC should be further investigated as a potentially useful marker for identifying patients at higher risk of recurrence, who might benefit from closer follow-up and more aggressive adjuvant therapy. In other oncological settings, increasing evidence of relaxin being produced by cancer cells is prompting efforts to synthesize human relaxin-2 analogs capable of acting as antagonists and limiting tumor growth.

Benign mesothelial cells in lymph nodes and lymphatic spaces associated with ascites.

Intra-nodal mesothelial cells are assumed to be indicative of metastatic mesothelioma. The invasion of benign mesothelial cells into lymph nodes is an extraordinary complication of different (mostly inflammatory) disorders involving the serosal cavities. In a cirrhotic patient with recurrent ascites, this report describes the first case of mesothelial cell spreading into lymphatic vessels, coexisting with non-malignant inclusions of mesothelial cells in multiple abdominal lymph nodes.

Multiple sporadic gastrointestinal stromal tumors concomitant with ampullary adenocarcinoma: a case report with KIT and PDGFRA mutational analysis and miR-221/222 expression profile.

GISTs originating multifocally at different GI sites, in patients lacking familial syndromes, could be interpreted as recurrent/metastatic disease. MiR-221/222 have recently been identified as regulators of KIT expression in GISTs. We report the first case of synchronous GISTs in the stomach and duodenum concomitant with an ampullary adenocarcinoma. Different CD117 expression patterns could be related to different KIT mutational status in the two lesions: gastric GIST showed a dot-like pattern and lacked KIT mutations; duodenal GIST had a strong membranous expression pattern, likely due to KIT exon 9 duplication, which is associated with lower response to imatinib. MiR-221/222 were downregulated in GISTs as compared with normal tissue (p<0.05) and expressed increased levels in the gastric GIST as compared with duodenal one (p<0.05). Our data support an independent origin of the two GISTs. Determining whether these tumors are multiple primaries or recurrencies is helpful to predict their malignancy and to select proper treatment.

Four cases of solitary fibrous tumour of the eye and orbit: one with sarcomatous transformation after radiotherapy and one in a 5-year-old child's eyelid.

BACKGROUND: Solitary fibrous tumour (SFT) is quite a rare neoplasm involving the eye and the orbit. It is described as showing benign behaviour in adults, but malignant cases are exceptionally reported in this location. This report describes four new cases of SFT/giant cell angiofibroma (GCA) of the eyelid and orbit, one in a 5-year-old child, and one with sarcomatous dedifferentiated transformation occurring 9 years after radiotherapy. METHODS: Four cases of ocular SFT/GCA were retrieved from the database of the Pathological Anatomy Unit, University of Padova; immunohistochemistry and RT-PCR were used to identify COL1A1-PDBGF fusion gene transcripts in all cases. RESULTS: In case 1, late relapse 9 years later was characterised by abrupt transition into a high-grade component, associated with a non-distinctive high-grade sarcomatous area. The latter component was CD34, CD99 and Bcl2 negative and smooth muscle actin positive. Molecular characterisation showed the absence of COL1A1-PDGFB fusion transcripts in cases 1, 3 and 4, excluded diagnosis of giant cell fibroblastoma in all cases. Analysis could not be performed in case 2. CONCLUSIONS: An eyelid SFT/GCA in a 5-year-old child is the youngest case reported in the literature, indicating that the tumour is not exclusive to adults. The case with sarcomatous transformation, with dedifferentiated features occurring 9 years after radiotherapy, raises some questions about the choice of treatment for ocular SFT, in which excision is sometimes difficult without devastating surgery.

C-Kit SCF receptor (CD117) expression and KIT gene mutation in conjunctival pigmented lesions.

PURPOSE: To investigate the presence of KIT gene mutations and immunoreactivity in 85 conjunctival melanocytic tumours and to clarify the role of KIT as a potential therapeutic target in this group of patients. METHODS: Eighty-five conjunctival pigmented tumours [27 melanomas, 12 primary acquired melanosis (PAMs) and 46 nevi] were immunostained for KIT. Intensity and pattern of expression were evaluated. Molecular analysis to identify KIT mutations was performed in 15 selected cases (tumour-rich areas >50%). KIT immunostaining score and pattern were statistically related to patients' age, sex, diagnostic category, presence of relapse, disease-free survival, presence of metastases, metastasis-free survival, limbal versus nonlimbal tumour location and thickness of melanomas. RESULTS: KIT stains were documented in 48% of melanomas, 50% of PAMs and 24% of nevi. The mean score of KIT staining in the melanomas/PAMs group was significantly different from nevi (p = 0.0076). No statistically significant differences were detected between either c-kit immunostaining score or pattern and each of the other clinico-pathologic parameters considered. No KIT gene mutations were detected in melanomas and nevi. A silent mutation/polymorphism in KIT exon 13 was found in one PAM. CONCLUSIONS: Despite the high level of KIT immunostains in PAMs and melanomas, this parameter seems not to be a good predictor of the presence of molecular mutations. KIT-activating mutations should be considered an uncommon event in this tumour.

mTOR expression and prognosis in elderly patients with laryngeal carcinoma: uni- and multivariate analyses.

Cancer is common in the elderly, who may also be frail, which can complicate the choice of the best therapeutic approach. We sought to examine whether the serine-threonine kinase mTOR, a "master switch" in cancer cells that modulates metabolism, the cell cycle, and apoptosis, might help in clinical decision-making. The aim of the present study was thus to assess the potential prognostic role of mTOR in elderly patients with laryngeal carcinoma (LSCC). mTOR expression was determined immunohistochemically in 54 consecutive elderly (≥65 years old) patients with LSCC. On univariate analysis, nodal involvement and pathological stage correlated strongly with the elderly LSCC patients' prognosis in terms of disease recurrence rate and disease-free survival (DFS). Patients whose mTOR expression was >35.3% had a significantly higher recurrence rate (p=0.003) and shorter DFS (p=0.013). In the multivariate model, N status (p=0.001) and mTOR expression (p=0.026) maintained an independent prognostic significance in relation to DFS. mTOR probably influences the aggressive LSCC phenotype in elderly patients and its expression in elderly LSCC cases can be considered a prognostic marker potentially useful for identifying patients at higher risk of disease recurrence, and N0 patients at higher risk of recurrence who may benefit from more aggressive treatment. Since rapalogs (as mTOR inhibitors) might have an effect on LSCC, further investigations are needed to ascertain these agents' role in therapeutic strategies for advanced LSCC in elderly patients.