Kirsten Rat Sarcoma (KRAS) is the most commonly mutated oncogene in colorectal carcinoma (CRC). We have previously reported the interactions between microsatellite instability (MSI), DNA promoter methylation, and gene expression. In this study, we looked for associations between KRAS mutation, gene expression, and methylation that may help with precision medicine. Genome-wide gene expression and DNA methylation were done in paired CRC tumor and surrounding healthy tissues. The results suggested that (a) the magnitude of dysregulation of many major gene pathways in CRC was significantly greater in patients with the KRAS mutation, (b) the up- and down-regulation of these dysregulated gene pathways could be correlated with the corresponding hypo- and hyper-methylation, and (c) the up-regulation of CDKN2A was more pronounced in tumors with the KRAS mutation. A recent cell line study showed that there were higher CDKN2A levels in 5-FU-resistant CRC cells and that these could be down-regulated by Villosol. Our findings suggest the possibility of a better response to anti-CDKN2A therapy with Villosol in KRAS-mutant CRC. Also, the more marked up-regulation of genes in the proteasome pathway in CRC tissue, especially with the KRAS mutation and MSI, may suggest a potential role of a proteasome inhibitor (bortezomib, carfilzomib, or ixazomib) in selected CRC patients if necessary.

BACKGROUND: Nail squamous cell carcinoma (NSCC) is the most frequent ungual malignant tumor, but its incidence remains low. The histopathological description is sparse. We aim to characterize NSCC histopathological aspects, search for a correlation with clinical subtypes, and investigate immunohistochemistry expression of p16, p53, and Ki67.
METHODS: This retrospective study collected NSCC diagnosed in our dermatology department between 2007 and 2021. The histopathological features were correlated with the clinical signs and immunohistochemistry.
RESULTS: A total of 48 patients were included, and immunohistochemistry was available for 36 of them. Two histopathological patterns became prominent: a blue-basaloid type characterized by koilocytosis (p < 0.001), and a pink-keratinizing type. Mean ages were similar when comparing basaloid and periungual versus keratinizing and subungual (p < 0.001). p16 was positive in 31 of 36 cases: 18 basaloid and 13 keratinizing (p = 0.167). p53 and Ki67 were all abnormal.
CONCLUSIONS: Our study described two histopathological NSCC subtypes and associated them with the two clinical subtypes: the blue-basaloid type, HPV-induced, in situ, of periungual localization in younger males; and the pink-keratinizing type, non-HPV-induced, invasive, of subungual site, in elderly. Immunohistochemistry was not contributing on its own, but p16 positivity associated with basaloid histopathological profile helps support HPV etiology.

There is limited understanding of epidemiology and time trends of human papilloma virus (HPV)-driven head and neck cancers (HNC) in Japan, especially outside of the oropharynx. To assess HPV-driven HNC, a non-interventional study (BROADEN) of HNC patients diagnosed in 2008-2009 and 2018-2019 was conducted in Japan. Adult patients with oropharyngeal, nasopharyngeal, laryngeal, hypopharyngeal or oral cavity cancers were included in this study. HPV was centrally tested using p16INK4a immunohistochemistry, HPV-DNA PCR and HPV E6*I mRNA. HPV attributability required positivity in at least two tests (p16INK4a immunohistochemistry, HPV-DNA PCR, HPV E6*I mRNA) in the oropharynx, and HPV-DNA and HPV E6*I mRNA positivity for non-oropharynx sites. Nineteen hospitals included a total of 1108 patients, of whom 981 had valid samples. Men accounted for 82% of HNC diagnoses. Patients in the earlier cohort were younger and included a higher percentage of smokers. There was an increasing trend of HPV-driven oropharyngeal cancer over the last decade, from 44.2% to 51.7%. HPV attribution in nasopharyngeal cancers was 3.2% in 2008-2009 and 7.5% in 2018-2019; and 4.4% and 0% for larynx respectively. In total, 95.2% of HPV-driven HNC were attributed to HPV genotypes included in the 9-valent HPV vaccine being HPV16 the most prominent genotype. These results suggest that an epidemiologic shift is happening in Japan, with a decrease in smoking and alcohol use and an increase in HPV-driven HNC. The increasing trend of HPV-driven HNC in Japan highlights the need for preventive strategies to mitigate the rise of HPV-driven HNC.

OBJECTIVE: Investigate the association between p16/Ki-67 dual stain cytology test (DST) results, obtained prior to- and 6 months after LLETZ surgery for treatment of CIN, and the follow-up regimen three years after treatment.
METHODS: Secondary analysis of a prospective cohort study. Cervical cytology samples were obtained just prior to- and 6 months after LLETZ and underwent conventional liquid-based cytology (LBC) and p16/Ki-67 dual staining, as well as high-risk HPV genotyping. Clinical management after the LLETZ was according to Belgian national guidelines, with clinicians being blinded to DST results at both time points. Case records were reviewed in 01/2023 to document the follow-up regimen on average three years afterwards: women had either been advised to return to routine screening (i.e., three-annual LBC testing according to the Belgian guideline at that time), or were still subject to more frequent posttreatment surveillance (i.e., more frequent visits because of persistent hrHPV infection or absence of cytological regression).
RESULTS: The follow-up regimen was recorded in 79/110 women originally recruited (72%). The need for continued intense posttreatment surveillance was associated with hrHPV infection 6 months after treatment (79.3% vs. 18.0%, p < 0.001), a positive DST result at baseline and follow-up (41.4% vs. 84.0%, p < 0.001-55.2% vs. 16.0%, p < 0.001), and persistent cytological anomalies at 6 months (at an ASCUS or worse threshold, 37.9% vs. 16.0%, p = 0.028). In multivariable logistic regression analysis, a positive DST at baseline (aOR 20.1, 95%CI 2.03-199.1) was independently associated with the need for intense post-treatment surveillance multiple years after treatment.
CONCLUSIONS: This exploratory study suggests a possible role of dual-stain cytology in predicting treatment outcome multiple years after LLETZ surgery.

Fluoroedenite-induced pleural mesothelioma (FE-induced-PM) is a rare and small subset of PM that shares with its asbestos-induced counterpart the same aggressive biological behavior and poor prognosis, but that differs from it from a pathogenetic point of view as it is associated with exposure to fluoroedenite, a carcinogenic agent that shows similarities with tremolite amphibolic asbestos fibers. Although it has been demonstrated that asbestos-induced PMs frequently harbor CDKN2A homozygous deletion and that the immunohistochemical loss of MTAP may represent a cheap and reliable surrogate marker for this molecular alteration, little is known about the molecular landscape and the reliability of MTAP immunohistochemistry in this peculiar subset of PM. The study herein presented investigated the prevalence of CDKN2A homozygous deletion and its concordance with MTAP immunohistochemical status on a cohort of 10 cases of FE-induced-PM from patients with environmental exposure to FE fibers, who were residents in the small town of Biancavilla (Sicily, Italy) or nearby areas. CDKN2A homozygous deletions were found in 3 out of 10 cases (30%) and all these cases showed concomitant cytoplasmic loss of MTAP with a concordance rate of 100%. Despite the relatively low number of cases included in our series, MTAP immunohistochemistry seemed to represent a reliable immunohistochemical surrogate marker of CDKNA homozygous deletion even in this subset of PMs.

BACKGROUND: Each high-risk HPV genotype has different oncogenic potential, and the risk of CIN3+ varies according to genotype. We evaluated the performance of different strategies of HPV-positivity triage combining cytology, p16/ki67 dual staining (DS), and extended genotyping.
METHODS: Samples from 3180 consecutive women from the NTCC2 study (NCT01837693) positive for HPV DNA at primary screening, were retrospectively analyzed by the BD Onclarity HPV Assay, which allows extended genotyping. Genotypes were divided into three groups based on the risk of CIN3+. HPV DNA-positive women were followed up for 24 months or to clearance.
RESULTS: Combining the three groups of genotypes with cytology or DS results we identify a group of women who need immediate colposcopy (PPV for CIN3+ from 7.8 to 20.1%), a group that can be referred to 1-year HPV retesting (PPV in those HPV-positive at retesting from 2.2 to 3.8), and a group with a very low 24-month CIN3+ risk, i.e. 0.4%, composed by women cytology or DS negative and positive for HPV 56/59/66 or 35/39/68 or negative with the Onclarity test, who can be referred to 3-year retesting.
CONCLUSIONS: Among the baseline HPV DNA positive/cytology or DS negative women, the extended genotyping allows to stratify for risk of CIN3+, and to identify a group of women with a risk of CIN3+ so low in the next 24 months that they could be referred to a new screening round after 3 years.
BACKGROUND: Italian Ministry of Health (grant number RF-2009-1536040). Hologic-Genprobe, Roche Diagnostics, and Becton & Dickinson provided financial and non-financial support.

Borderline Brenner tumors (BBT) have a range of morphology that shows considerable overlap with that of malignant Brenner tumors (MBT). In particular, two histological patterns of BBT can be particularly challenging: 1) BBT with intraepithelial carcinoma (BBT-IEC) and 2) BBT with a small nested pattern (BBT-SNP). BBT-IEC is characterized by a tumor with the low-power non-infiltrative silhouette of a conventional BBT, but with increased cytological atypia and mitotic activity similar to that of MBT. Conversely, BBT-SNP is characterized by a complex proliferation of small tumor nests that closely resemble the infiltrative growth pattern of MBT, but without the obligate cytologic atypia and mitotic activity of MBT. We suggest that the combination of p16, p53 and Ki-67 may be helpful in distinguishing these 2 patterns of BBT from both conventional BBT and from MBT. While both conventional BBT and BBT-IEC show a null pattern of p16 expression, our case of BBT-IEC showed aberrant p53 overexpression, albeit with a maturation pattern similar to that described for TP53 mutant mucinous ovarian carcinoma and differentiated vulvar intraepithelial neoplasia (dVIN). Similarly, while BBT-SNP shows an infiltrative-like growth pattern similar to that of MBT, our case also showed a wild-type pattern of p53 expression and a Ki-67 proliferative index similar to areas with conventional BBT histology. In conclusion, in our small case series, we show that the use of immunohistochemistry for p53 and Ki-67 may help to distinguish challenging patterns of BBT from MBT. Further studies are needed to validate this finding in a larger case cohort.

UNASSIGNED: Information regarding the genetic alterations in extramammary Paget disease (EMPD) is scarce. This study investigated the significance of CDKN2A and MTAP alterations in EMPD progression using immunohistochemistry and panel DNA sequencing. In total, 24 invasive/metastatic EMPD cases were included in this study. The immunoexpression of p16 and MTAP in the primary in situ, primary invasive, and metastatic tumor components was evaluated. Panel DNA sequencing was performed for metastatic tumor components in 5 of the 24 cases. Immunoexpression of p16 in the in situ tumor component was at least partially preserved in all 19 tested cases (100%). By contrast, the invasive tumor component was diffusely or partially lost in 18 (81.8%) of 22 tested cases. Regarding the foci of lymph node metastasis, 13 (81.2%) of the 16 patients showed a significant loss of p16 expression. Loss of MTAP immunoexpression was observed less frequently compared with the loss of p16 expression. CDKN2A homozygous deletions were confirmed in all 5 tested cases by sequencing, whereas MTAP deletions were detected in only 2 cases. In conclusion, p16 expression loss and CDKN2A deletions can be frequently seen in invasive/metastatic cases of EMPD.

The purpose of this study was to assess the clinicopathological features of oropharyngeal cancer patients in Jordan based on their HPV status. Sixty-nine biopsies from two hospitals were included. Tissue microarrays were prepared from formalin-fixed paraffin-embedded (FFPE) specimens and stained with antibodies for CDKN2A/P16, EGFR, PI3K, PTEN, AKT, pS473AKT, PS2mTOR, and TIMAP. The cohort was divided according to P16 expression. Chi-square test and survival analyses were employed to evaluate the variations among the study variables and determine the prognostic factors, respectively. P16 expression was found in 55.1% of patients; however, there was no significant association between P16 expression and the patients\' clinicopathological features. The Kaplan-Meier test revealed that smoking in P16-positive group and younger age (< 58 years) negatively impacted disease-free survival (DFS) (P = 0.04 and P = 0.003, respectively). Multivariate Cox regression test indicated that smoking, age, PI3K, and AKT were negative predictors of DFS (P = 0.021, P = 0.002, P = 0.021, and P = 0.009, respectively), while TIMAP was a positive predictor (P = 0.045). Elevated P16 expression is found in more than half of the patients\' specimens. DFS is negatively affected by younger age and the combined effect of smoking and P16 overexpression. TIMAP is overexpressed in P16-positive oropharyngeal cancer, and it is a favorable predictor of DFS.

Epithelioid glioblastoma (eGBM) is a rare subtype of GBM. Given the update of the definition of GBM, the understanding of the molecular characteristics and prognosis of \"true\" adult eGBM remains limited. Herein, we retrospectively analyzed the clinicopathological data of 39 adult eGBM cases. Adult eGBM primarily affected females, with a male-to-female ratio of 1:2.3. The average age of diagnosis was 53 years, and the tumor affected the temporal lobe in 41% of cases (16/39, 41%). Microscopically, the tumors consisted mainly or entirely of epithelioid cells. Perivascular infiltration (10/39, 25.6%) and leptomeningeal dissemination (7/39, 17.9%) were not uncommon. BRAF V600E mutation was detected in 40.9% of cases (n = 9/22). Next-generation sequencing revealed that CDKN2A/B homogeneous deletion was the most frequently mutated gene (8/10, 80%), followed by TERT promoter mutation (7/10, 70%), Cyclin-dependent kinases 4 or 6 (CDK4/6) amplification (5/10, 50%) and BRAF V600E mutation (50%, 5/10). Notably, the incidence of ARID1B mutation in eGBM was 50% (5/10), representing the first report of such a mutation in this subtype of GBM. ARID1B was known to be a subunit of the SWI/SNF chromatin remodeler. Chromosome analysis showed a 7+/10- signature in 90% (9/10) cases. Adult eGBM carried a dismal prognosis compared to GBM with IDH and H3 wild-type (typical GBM) (OS: 13.89 vs 24.30 months; P = .003) and even typical GBM without MGMT promoter methylation (OS: 13.89 vs 22.08 months; P = .036). Based on these findings, it can be concluded that adult eGBM harbors a high frequency of the 7+/10- signature and alterations in the MAPK pathway, SWI/SNF complex and cyclin-related genes and portends an extremely poor prognosis.