Feasibility of using P16 methylation as a cytologic marker for esophageal squamous cell carcinoma screening: A pilot study.

BACKGROUND: Early diagnosis and treatment of esophageal squamous cell dysplasia (ESCdys) and esophageal squamous cell carcinoma (ESCC) could significantly reduce the incidence and mortality of ESCC. This pilot study aimed to investigate whether P16/CDKN2A methylation could serve as a cytologic biomarker for early detection of ESCdys and ESCC. METHODS: Paired esophageal biopsy and cytology specimens (exfoliated cells) were obtained from subjects at different stages of ESCC development. The methylation status of P16 gene in these two specimen types was determined using a 115-bp MethyLight assay. Categorical data were compared by the Chi-square test. Logistic regression was performed to assess adjusted odds ratios of P16 methylation associated with ESCC and ESCdys. Prediction models for identifying individuals at risk of ESCC and high-grade ESCdys (high-grade intraepithelial neoplasia, HGIN) were developed by multivariable logistic regression. Diagnostic performance was evaluated using receiver operating characteristic (ROC) analysis. Internal validation of the prediction models was performed using the 1000-bootstrap resample. RESULTS: A total of 105 subjects with diagnoses ranging from normal mucosa through ESCC were included in this study. An increase in P16 methylation frequency was observed with increasing severity of esophageal lesions (p for trend <0.001). In the adjusted logistic regression models, P16 methylation in cytology specimens was positively associated with ESCC and ESCdys risk, whereas P16 methylation in biopsy specimens was only associated with a higher risk of developing ESCC. The predictive capacity of base model I (AUC, 0.816) for ESCC and HGIN was significantly increased by adding P16 methylation in cytology specimens (model III; AUC, 0.882; p = 0.043), but not P16 methylation in biopsy specimens (model II; AUC, 0.850; p = 0.225). Bootstrap validation showed optimism-corrected AUC of 0.789 for model I, 0.822 for model II, and 0.854 for model III. CONCLUSION: P16 methylation as a cytologic marker was associated with the ESCC development and has the potential for application in minimally invasive ESCC screening.

Evaluation of the Impact of Intratumoral Heterogeneity of Esophageal Cancer on Pathological Diagnosis and P16 Methylation and the Representativity of Endoscopic Biopsy.

BACKGROUND: P16 methylation is expected to be potential diagnostic and therapeutic targets for esophageal cancer (EC). The intratumoral heterogeneity (ITH) of EC has been mentioned but has not been quantitatively measured yet. We aimed to clarify the impact of ITH on pathological diagnosis and P16 methylation, and the concordance between endoscopic biopsy and the corresponding surgically resected tissue. METHODS: We designed a systematic sampling method (SSM) compared with a general sampling method (GSM) to obtain EC tumor tissue, tumor biopsy, and normal squamous epithelium biopsy. MethyLight assay was utilized to test P16 methylation. All specimens obtained by the SSM were pathologically diagnosed. RESULTS: A total of 81 cases were collected by the GSM, and 91.4% and 8.6% of them were esophageal squamous cell carcinomas (ESCCs) and esophageal adenocarcinomas (EADs), respectively. Nine SSM cases were 100.0% ESCCs. The positive rates of P16 methylation of the GSM tumor and normal tissues were 63.0% (51/81) and 32.1% (26/81), respectively. For SSM samples, tumor tissues were 100.0% (40/40) EC and 85.0% (34/40) P16 methylated; tumor biopsy was 64.4% (29/45) diagnosed of EC and 68.9% P16 methylated; the corresponding normal biopsies were 15.7% (8/51) dysplasia and 54.9% (28/51) P16 methylated. The concordance of pathological diagnosis and P16 methylation between tumor biopsy and the corresponding tumor tissue was 75.0% and 62.5%, respectively. CONCLUSION: The SSM we designed was efficient in measuring the ITH of EC. We found inadequate concordance between tumor biopsy and tissue in pathological diagnosis and P16 methylation.

HPV infection and p16 promoter methylation as predictors of ASC-US/LSIL progression.

BACKGROUND: Although patients found to have atypical squamous cells of undetermined significance (ASC-US) and low-grade squamous intraepithelial lesions (LSILs) on Papanicolaou (Pap) testing are treated conservatively, 5.2% to 18.8% of them progress to high-grade squamous intraepithelial lesions (HSILs). The objective of the current study was to identify predictors of progression to HSIL and determine what percentage of ASC-US/LSIL cases harbor cervical intraepithelial neoplasia of grade 2 or higher. METHODS: The current study included 381 consecutive cases with ASC-US/LSIL. After the exclusion of 87 cases because of a history of dysplasia or loss to follow-up, 165 cases with follow-up cytology were used to analyze predictive factors of progression to HSIL, and 129 cases that underwent immediate tissue biopsy were subjected to correlation analysis between cytology and histology. Disease regression was defined as a reversion to normal or benign cellular changes, disease persistence as maintenance at ASC-US/LSIL, and disease progression as progression to HSIL. Data regarding clinical parameters were obtained from medical records. Methylation-specific polymerase chain reaction was performed using cytology samples to evaluate methylation of the p16 promoter. RESULTS: Of 165 cases, 131 (79.4%) regressed, 23 (13.9%) were persistent, and 11 cases (6.7%) progressed. Human papillomavirus infection was more common in women with disease progression than in those with disease regression or persistence (P = .033). Promoter methylation of p16 in the cytology sample was more common in cases that progressed (5 of 6 cases) than in cases that regressed (0 of 8 cases). Twenty-three of 129 cases (17.8%) were found to harbor cervical intraepithelial neoplasia of grade 2 or higher on immediate tissue biopsy. CONCLUSIONS: Human papillomavirus infection and p16 promoter methylation might be valuable surrogate markers of disease progression from ASC-US/LSIL to HSIL.

Diagnostic value of p16 methylation for malignant pleural effusion a meta-analysis / Valor diagnóstico de la metilación p16 en el derrame pleural maligno un meta-análisis

OBJECTIVE: To evaluate the overall diagnostic performance of the p16 methylation for diagnosing malignant pleural effusion (MPE). METHODS: All published literature in English and Chinese were reviewed. Sensitivity, specificity, likelihood ratio and diagnostic odds ratio (DOR) were pooled by using random-effects model or fixed-effects model. Summary receiver operating characteristic (SROC) curve was used to evaluate the overall diagnostic value. RESULTS: Six studies were included with a total of 378 cases. The sensitivity, specificity, positive likelihood ratio (PLR), negative likelihood ratio (NLR) and DOR of p16 methylation in the diagnosis of MPE were 0.41 [95% confidence interval (CI) 0.35, 0.48], 0.97 [95% CI 0.93, 0.99], 9.57 [95% CI 4.53, 20.20], 0.61 [95% CI 0.45, 0.82] and 19.82 [95% CI 8.35, 47.04], respectively. The area under the curve (AUC) was 0.864. CONCLUSION: Pleural p16 methylation test plays a useful role in the diagnosis of MPE.

OBJETIVO: Evaluar el rendimiento diagnóstico general de la metilación p16 para el diagnóstico del derrame pleural maligno (DPM). MÉTODOS: Se revisó toda la literatura publicada en inglés y chino. La sensibilidad, especificidad, razón de verosimilitud, y el odds-ratio diagnóstico (DOR) fueron agrupados mediante el modelo de efectos aleatorios o el modelo de efectos. La curva de las características operativas de resumen del receptor (SROC) fue usada para evaluar el valor diagnóstico general. RESULTADOS: Se incluyeron seis estudios con un total de 378 casos. La sensibilidad, especificidad, razón de verosimilitud positiva (PLR), razón de verosimilitud negativa (NLR) y el DOR de la metilación p16 en el diagnóstico de DPM, fueron 0.41 [95% intervalo de confianza (IC) 0.35 0.48], 0.97 [95% IC 0.93, 0.99], 9.57 [95% IC 4.53, 20.20], [95% IC 0.45, 0.82] 0.61 y 19.82 [95% IC 8.35, 47.04], respectivamente. El área bajo la curva (AUC) fue 0.864. CONCLUSIÓN: La prueba de metilación p16 pleural desempeña un papel útil en el diagnóstico del DPM.