Endometrial Metaplastic/Reactive Changes Coexistent with Endometrial Hyperplasia and Carcinoma: A Morphological and Immunohistochemical Study

The aim of this study was to assess the relationship between endometrial metaplastic/reactive changes (EMRCs) and endometrial neoplastic lesions. Twenty cases of “simple” (without architecture complexity) EMRCs coexistent with endometrial malignant/premalignant lesions, twenty cases of neoplasia-unassociated EMRCs, and eight cases of complex metaplastic lesions were assessed by immunohistochemistry. EMRCs coexisted with endometrioid carcinoma (n = 12), atypical endometrial hyperplasia (n = 3), serous carcinoma (n = 2), and clear cell carcinoma (n = 3). Neoplasia-associated EMRCs showed a mean Ki67 labeling index of 12.6% (range 0–30%); with nuclear atypia in 16/20 (80%) cases; diffuse p16 expression in 15/20 (75%) cases; and heterogeneous ER, PR, and vimentin expression. Compared to the associated neoplasia, EMRCs showed a lower Ki67 expression (p < 0.001) and higher p16 expression (p < 0.001). No EMRC case showed mitotic activity, PTEN loss, MMR deficiency, nuclear β-catenin, p53-mutant pattern, Napsin A, or AMACR expression. No significant differences were found between neoplasia-associated and neoplasia-unassociated EMRCs. Complex metaplastic lesions showed a lower Ki67 expression than EMRCs (p = 0.044) and PTEN loss in 5/8 cases, even in the absence of nuclear atypia. In conclusion, neoplasia-associated simple EMRCs may show evident atypia and a worrisome immunophenotype, but no data support their involvement in endometrial carcinogenesis. Architectural complexity appears as a crucial factor to identify precancerous lesions.

P16 expression and clinicopathological features of oral and oropharyngeal squamous cell carcinoma

Background: There is an epidemiological shift in head and neck squamous cell carcinoma (HNSCC) attributable to HPV infection. HPV positive HNSCC has unique biology, risk factors, clinicopathological characteristics and outcome. There is a large variation in the published prevalence of HPV-related HNSCCs in India ranging from 7 to 78.7%. This study aims to find the P16 expression in the oral cavity and oropharyngeal SCC, thereby prevalence of HPV in our setting and to define the clinicopathological characteristics of HPV positive tumours in our setting.Methods: 210 specimens of primary Oral squamous cell carcinoma (OSCC) and Oropharyngeal Squamous cell carcinoma (OPSCC) were included. Immunohistochemistry was done using monoclonal mouse p16 antibody. Clinical details of each case were collected. Analysis was done using SPSS software and the association of P16 and clinicopathological variables were calculated using Fishers exact test.Results: P16 positive expression is observed only in 1/122 (0.82%) of OSCC and 8/88 (9%) of OPSCC. P16 positivity showed significant association with Grade of tumor (p= 0.008) and histological variant of SCC (p=0.00). 77.7% of P16 positive tumours are Grade 2 and 66.6% of Basaloid SCC was P16 positive. There is no significant association between p16 expression and other variables (subsite, age, gender, alcoholism, smoking, betel chewing and stage).Conclusions: P16 positivity was higher in oropharyngeal than in oral cancer. However, the HPV positivity rates are lower than other parts of India.

Endometrial Stromal Expression of ER, PR, and B-Catenin Toward Differentiating Hyperplasia Diagnoses

Background. The interpretation of histopathological changes of endometrial hyperplasia with or without atypia can be challenging. We aim to investigate the role of specific immunohistochemical markers in the endometrial stroma to classify endometrial hyperplasia in difficult cases. Methods and Results. We retrospectively reviewed and reclassified (WHO 2014): 47 specimens with endometrial hyperplasia without atypia, 33 with atypical hyperplasia (AH), and 13 endometrioid adenocarcinomas. We performed IHC for B-catenin, E-cadherin, p16, estrogen receptors and progesterone receptors, and B-cell lymphoma 2 (BCL2). Percentage of positive stromal cells was calculated. B-catenin was equally expressed in the stroma of both hyperplasia and AH (mean 60%, 50%; P = .17) and was absent from adenocarcinoma (0%, hyperplasia vs adenocarcinoma; P < .0001, AH vs adenocarcinoma; P < .0001). E-cadherin was not expressed in the stroma of any lesion, while p16 expression levels were not statistically different (hyperplasia vs AH; P = .46, hyperplasia vs adenocarcinoma; P = .22, AH vs adenocarcinoma; P = .48). Estrogen and progesterone were highly identified in stromal cells of hyperplasia (80%) and diminished in AH (respectively, at 30% and 60%, hyperplasia vs AH; P < .0001), and in adenocarcinoma (0% and 40%, respectively). Finally, BCL2 was not differentially expressed (hyperplasia vs AH; P = .33, hyperplasia vs adenocarcinoma; P = .17, AH vs adenocarcinoma; P = .36). Conclusion. Estrogen and progesterone were strongly expressed in stroma exclusively of hyperplasia, while B-catenin was particularly expressed in hyperplasia and AH. Use of these markers can be useful in the differential diagnosis of hyperplasia from AH, and AH from adenocarcinoma in challenging cases.

Circulating p16-Positive and p16-Negative Tumor Cells Serve as Independent Prognostic Indicators of Survival in Patients with Head and Neck Squamous Cell Carcinomas

Background: Decisions regarding the staging, prognosis, and treatment of patients with head and neck squamous cell carcinomas (HNSCCs) are made after determining their p16 expression levels and human papillomavirus (HPV) infection status. Methods: We investigated the prognostic roles of p16-positive and p16-negative circulating tumor cells (CTCs) and their cell counts in HNSCC patients. We enrolled patients with locally advanced HNSCCs who received definitive concurrent chemoradiotherapy for final analysis. We performed CTC testing and p16 expression analysis before chemoradiotherapy. We analyzed the correlation between p16-positive and p16-negative CTCs and HPV genotyping, tissue p16 expression status, response to chemoradiotherapy, disease-free survival, and overall survival. Results: Forty-one patients who fulfilled the study criteria were prospectively enrolled for final analysis. The detection rates of p16-positive (>0 cells/mL blood) and p16-negative (≥3 cells/mL blood) CTCs were 51.2% (n = 21/41) and 70.7%, respectively. The best responses of chemoradiotherapy and the p16 positivity of CTCs are independent prognostic factors of disease progression, with hazard ratios of 1.738 (95% confidence interval (CI): 1.031–2.927), 5.497 (95% CI: 1.818–16.615), and 0.176 (95% CI: 0.056–0.554), respectively. The p16 positivity of CTCs was a prognostic factor for cancer death, with a hazard ratio of 0.294 (95% CI: 0.102–0.852). Conclusions: The p16-positive and p16-negative CTCs could predict outcomes in HNSCC patients receiving definitive chemoradiotherapy. This non-invasive CTC test could help stratify the risk and prognosis before chemoradiotherapy in clinical practice and enable us to perform de-intensifying therapies.

Differential p16 expression levels in the liver, hepatocytes and hepatocellular cell lines

Background One of the most frequently deleted genes in cancer is CDKN2A encoding p16. This protein is often overexpressed in senescent cells, while its suppression can bypass the oncogene-induced senescence to enable transformation and tumorigenesis. The roles of the protein p16 are recently being expanded from the cell cycle progression regulator to the cellular regulator interacting in several different pathways. Yet data on its liver and liver cells’ expression are inconclusive. Methods The expression of the p16 gene in liver and liver cells was determined by RT-qPCR and compared to its protein amounts by western blotting. Results p16 is expressed at low levels in the liver and rat hepatocytes. Its expression varies from none to the considerable levels in the examined hepatocellular carcinoma cell lines (FaO and HepG2) and in immortalized mouse hepatocytes. Such significant expression differences of an important cellular regulator warrant the need to closely examine the differences in biochemical pathways correlated with the p16 expression when using hepatocytes and hepatoma liver models.

2020 WHO Classification of Female Genital Tumors

The 2020 WHO classification is focused on the distinction between HPV-associated and HPV-independent squamous cell carcinoma of the lower female genital organs. Differentiating according to HPV association does not replace the process of grading; however, the WHO classification does not recommend any specific grading system. VIN are also differentiated according to whether they are HPV(p16)-associated. HPV-independent adenocarcinoma (AC) of the cervix uteri has an unfavorable prognosis. Immunohistochemical p16 expression is considered to be a surrogate marker for HPV association. HPV-associated AC of the cervix uteri is determined using the prognostically relevant Silva pattern.

Increased PD-L1 and p16 expression are common in oropharyngeal squamous cell carcinoma

Overexpression of p16 is closely related to human papillomavirus (HPV)-associated oropharyngeal squamous cell carcinoma (SCC) and pertains a prognostic relevance. Programmed cell death 1-ligand 1 (PD-L1) is another important marker, as anti-PD-L1 immunotherapy is available. Retrospective analysis of 57 cases of the SCC involving oropharynx (27 cases), hypopharynx (5 cases), larynx (11 cases), and oral cavity (14 cases) was performed. Each case was scrutinized for the basaloid morphology, p16, and PD-L1 expression. Basaloid morphology was identified in 47% of total cases. The majority of basaloid SCC variants were located in the oropharynx (89%). High expression of p16 was mostly observed in the oropharynx. High PD-L1 expression was seen predominantly in oropharyngeal and hypopharyngeal locations. Further studies in a larger cohort are necessary to correlate PD-L1 and p16 expression with survival.

Breast Cancer and p16: Role in Proliferation, Malignant Transformation and Progression

The definition of new molecular biomarkers could provide a more reliable approach in predicting the prognosis of invasive breast cancers (IBC). The aim of this study is to analyze the expression of p16 protein in IBC, as well as its participation in malignant transformation. The study included 147 patients diagnosed with IBC. The presence of non-invasive lesions (NIL) was noted in each IBC and surrounding tissue. p16 expression was determined by reading the percentage of nuclear and/or cytoplasmic expression in epithelial cells of IBC and NIL, but also in stromal fibroblasts. Results showed that expression of p16 increases with the progression of cytological changes in the epithelium; it is significantly higher in IBC compared to NIL (p < 0.0005). Cytoplasmic p16 expression is more prevalent in IBC (76.6%), as opposed to nuclear staining, which is characteristic of most NIL (21.1%). There is a difference in p16 expression between different molecular subtypes of IBC (p = 0.025). In the group of p16 positive tumors, pronounced mononuclear infiltrates (p = 0.047) and increased expression of p16 in stromal fibroblasts (p = 0.044) were noted. In conclusion, p16 protein plays an important role in proliferation, malignant transformation, as well as in progression from NIL to IBC.

Prognostic Significance of a Scoring System Combining p16, Smoking, and Drinking Status in a Series of 131 Patients with Oropharyngeal Cancers

Background. Tobacco and alcohol are two main risk factors associated with head and neck squamous cell carcinoma (HNSCC). Studies showed that human papillomavirus (HPV) plays a role in the etiology of this cancer. HPV-positive oropharyngeal squamous cell carcinoma (OSCC) patients present in general a better response to conventional therapy and better overall survival (OS). However, OSCC is a heterogeneous disease regarding treatment. This study aimed to identify more effective prognostic factors associated with a poor clinical outcome for OSCC patients to improve treatment selection. Materials and Methods. OSCC patients diagnosed between 2007 and 2017, in two Belgian hospitals, were included. Demographic and clinicopathologic data were extracted from medical records. HPV status was determined through p16 immunohistochemistry. Univariable and multivariable Cox proportional hazard regression analyses allowed to identify variables prognostic for OS and recurrence-free survival (RFS). Kaplan–Meier survival curves have been assessed for survival. Results. The study included 131 patients. Statistics showed that monotherapies were significantly associated with a shorter OS; p16 overexpression was significantly associated with a weak consumption of tobacco or alcohol, and a high p16 expression was significantly associated with both longer RFS and OS. The study validated that tobacco and alcohol consumption were significantly correlated with poorer RFS and poorer OS. Only p16 expression trended to be significant for RFS when compared to smoking and drinking habits, while p16 upregulation and alcohol use were both vital for OS indicating that p16 is an independent and significant prognostic factor in OSCC patients. Finally, a scoring system combining p16, tobacco, and alcohol status was defined and was significantly associated with longer RFS and longer OS for nonsmoker and nondrinker p16-positive OSCC patients. Conclusions. This study confirmed that the overexpression of the p16 protein could be viewed as a factor of good prognosis for RFS and OS of OSCC patients. The prognostic significance of a scoring system combining p16 expression, smoking, and drinking status was evaluated and concluded to be a more effective tool to determine therapeutic orientations based on the risk factors for better treatment relevance and survival.