"Find Your Y": histological differences in early stage (pT) and post-treatment (ypT) oesophageal adenocarcinoma with implications for salvage endoscopic resection.

AIMS: Current guidelines offer limited strategies for managing recurrent/persistent oesophageal adenocarcinoma (EAC). Salvage endoscopic mucosal/submucosal resection (ER) shows promise in oesophageal squamous cell carcinoma, however its success in EAC is limited. We aimed to elucidate histological characteristics influencing salvage ER success in patients with low-stage, pretreated EAC. METHODS: We retrospectively reviewed 272 EAC tumours postoesophagectomy from five US centres and collected clinicopathological data including discontinuous growth (DG), defined as separate tumour foci ≥2 mm from the main tumour. We selected 101 patients with low-stage disease and divided them into treatment-naïve (n=70) and neoadjuvant therapy (n=31) groups. We compared the two groups and differences in clinical, histological and outcome characteristics were identified. RESULTS: In the entire cohort (n=272), DGs were identified in 22% of cases. Multivariate analysis revealed DGs as an independent prognostic factor for recurrence and positive oesophagectomy margins. Lymphovascular invasion (LVI) and background intestinal metaplasia predicted DG presence and absence, respectively. Compared with the treatment-naïve low T-stage subgroup, the pretreated subgroup exhibited higher incidence of poorly differentiated carcinoma (16% vs 46%, p=0.007), larger tumours (14 vs 30 mm, p<0.001), higher tumour, node, metastases stage (7% vs 30%, p=0.004), more nodal disease (7% vs 36%, p<0.001) and frequent DGs (1% vs 13%, p=0.030). CONCLUSIONS: In treated low T-stage EACs, DGs may contribute to suboptimal outcomes following salvage ER. Presence of LVI (as a surrogate for DGs) and poor differentiation in the absence of intestinal metaplasia in biopsy samples may serve as histological poor prognosticators in treated patients with EAC being considered for salvage ER.

Paediatric Crohn's disease: histologic findings at initial presentation.

BACKGROUND: Diagnosing paediatric Crohn's disease (CD) based on histology can present challenges. We evaluate the histological spectrum of treatment-naïve biopsies from children with CD and assess these findings' diagnostic and predictive value. METHODS: Three cohorts were identified: (1) 137 patients with CD, (2) 116 patients with ulcerative colitis (UC) and (3) 50 patients without inflammatory bowel disease. Biopsies from the gastrointestinal (GI) tract were re-examined for signs of active and chronic inflammation, including lymphocyte-pattern oesophagitis, focal enhancing gastritis and indicators of chronicity. Additionally, granulomas and microgranulomas (defined as clusters of 4-9 epithelioid histiocytes) were evaluated. RESULTS: Lymphocyte-pattern oesophagitis was observed in 15% of patients (n=20). Moderate-to-severe diffuse gastritis was noted in 50.4% of patients (n=68), while focal enhancing gastritis was identified in 11.1% (n=15). In terminal ileal biopsies, 46.1% exhibited activity and 5.3% showed features of chronicity. Active colitis was present in 73% of patients (n=100), with chronic colitis seen in 11.7% (n=16). Granulomas and microgranulomas were observed in 31.4% (43/137) and 48.9% (67/137) of patients, respectively. Notably, 30.7% (42/137) of patients with microgranulomas were without granulomas. Previously undetected microgranulomas were found in 20 of 27 cases. 2.5% of patients with UC and none of the control cohort showed microgranulomas. Lymphocyte-pattern oesophagitis was associated with an increased need for anti-tumor necrosis factor (TNF) therapy (p=0.007). CONCLUSIONS: GI microgranulomas, often overlooked, are specific to CD in the proper clinical context. Oesophageal lymphocytosis may predict a need for more aggressive treatment. The study brings to light under-recognised aspects of CD's histological diagnosis, including the oversight of microgranulomas, the high prevalence of diffuse gastritis and low prevalence of focal enhancing gastritis, the frequent absence of terminal ileitis and the infrequent occurrence of chronic colitis.

Molecular profiling of visible polypoid and invisible conventional intestinal-type low-grade dysplasia in patients with idiopathic inflammatory bowel disease.

AIMS: Little is known about the molecular features of visible polyps with low-grade intestinal-type dysplasia in patients with inflammatory bowel disease (IBD). To better understand their origins and biological potential, we sought to genomically profile these lesions and compare them with invisible low-grade dysplasia and sporadic adenomas from non-IBD patients. METHODS: 22 polyps within areas of colitis, 13 polyps outside areas of colitis, 10 foci of invisible dysplasia from patients with IBD and 6 sporadic tubular adenomas from non-IBD patients were analysed using the OncoPanel assay. RESULTS: Polyps arising in areas of colitis showed a greater spectrum of mutations, including APC, KRAS, FBXW7, TP53, ARID1A and TCF7L2. Polyps outside colitis and non-IBD sporadic adenomas showed a limited mutational profile, with APC and CTNNB1 mutations. Invisible dysplasia was characterised by TP53, CTNNB1 and KRAS alterations. Compared with dysplastic polyps, none of the invisible dysplastic foci showed APC alterations (73%-within colitis; p=0.0001, 92%-outside colitis; p<0.0001, 83%-sporadic adenomas; p=0.001). TP53 mutations were significantly higher in invisible dysplasia (50%) compared with polyps within colitis (9%; p=0.02) and outside colitis (8%; p=0.03). CONCLUSIONS: Molecular alterations in visible low-grade dysplastic polyps with conventional intestinal-type dysplasia from patients with IBD and sporadic adenomas from non-IBD patients overlap significantly. APC alterations appear to play a major role in the development of visible low-grade dysplastic lesions in patients with IBD, regardless of background colitis. As with IBD-associated colorectal cancers, TP53 mutations are an early event in the development of invisible, low-grade conventional intestinal-type dysplasia in patients with IBD.

Microbiota metabolized Bile Acids accelerate Gastroesophageal Adenocarcinoma via FXR inhibition.

Background: The incidence of Barrett esophagus (BE) and Gastroesophageal Adenocarcinoma (GEAC) correlates with obesity and a diet rich in fat. Bile acids (BA) support fat digestion and undergo microbial metabolization in the gut. The farnesoid X receptor (FXR) is an important modulator of the BA homeostasis. The capacity of inhibiting cancer-related processes when activated, make FXR an appealing therapeutic target. In this work, we assess the role of diet on the microbiota-BA axis and evaluate the role of FXR in disease progression. Results: Here we show that high fat diet (HFD) accelerated tumorigenesis in L2-IL1B mice (BE- and GEAC- mouse model) while increasing BA levels and enriching gut microbiota that convert primary to secondary BA. While upregulated in BE, expression of FXR was downregulated in GEAC in mice and humans. In L2-IL1B mice, FXR knockout enhanced the dysplastic phenotype and increased Lgr5 progenitor cell numbers. Treatment of murine organoids and L2-IL1B mice with the FXR agonist obeticholic acid (OCA) deacelerated GEAC progression. Conclusion: We provide a novel concept of GEAC carcinogenesis being accelerated via the diet-microbiome-metabolome axis and FXR inhibition on progenitor cells. Further, FXR activation protected with OCA ameliorated the phenotype in vitro and in vivo, suggesting that FXR agonists have potential as differentiation therapy in GEAC prevention.

ß2-microglobulin expression is associated with aggressive histology, activated tumor immune milieu, and outcome in colon carcinoma.

OBJECTIVES: We sought to assess the expression of human leukocyte antigen (HLA) proteins and ß2-microglobulin (B2M) in tumor cells and the relationship with immune microenvironment and outcome in colorectal cancer (CRC). METHODS: A total of 953 CRC cases were evaluated by immunohistochemistry for HLA class I, HLA class II, and B2M. The expression level of these biomarkers was correlated with clinicopathologic information, BRAF V600E and mismatch repair (MMR) proteins, and the quantitated expression levels of immune cells (CD8 and CD163) and immune regulatory proteins (FoxP3, programmed cell death 1 ligand 1 [PD-L1], and LAG3). RESULTS: We found that B2M-low tumors were statistically correlated with aggressive histologic features, including higher stage, higher grade, extramural venous invasion, perineural invasion, and distant metastasis. Expression of B2M was positively correlated (R2 = 0.3) and significantly associated with MMR-deficient tumors (P < .001); B2M-low tumors were also associated with an "immune cold"' microenvironment, including a reduced number of immune cells (CD8 and CD163), reduced expression of immune regulatory proteins by immune cells (PD-L1, FoxP3, and LAG3), and reduced tumor cell expression of PD-L1. These B2M-low tumors correlated with lower disease-specific survival (P = .018), a finding that maintained significance only for the proficient MMR cohort (P = .037). CONCLUSIONS: Our findings suggest that B2M expression may support predictive models for both outcome and checkpoint inhibitor therapy treatment response for colorectal adenocarcinoma.

Barrett's Esophagus and Associated Dysplasia.

Early detection of dysplasia and effective management are critical steps in halting neoplastic progression in patients with Barrett's esophagus (BE). This review provides a contemporary overview of the BE-related dysplasia, its role in guiding surveillance and management, and discusses emerging diagnostic and therapeutic approaches that might further enhance patient management. Novel, noninvasive techniques for sampling and surveillance, adjunct biomarkers for risk assessment, and their limitations are also discussed.

Clinical Significance and Prognostic Implications of Discontinuous Growth Pattern in Esophageal Adenocarcinoma: A Multi-Institutional Study.

The significance of discontinuous growth (DG) of the tumor to include tumor deposits and intramural metastasis in esophageal adenocarcinoma (EAC) is unclear. Esophagectomy specimens from 151 treatment-naïve and 121 treated patients with EAC were reviewed. DG was defined as discrete (≥2 mm away) tumor foci identified at the periphery of the main tumor in the submucosa, muscularis propria, and/or periadventitial tissue. Patients' demographics, clinicopathologic parameters, and oncologic outcomes were compared between tumors with DG versus without DG. DGs were identified in 16% of treatment-naïve and 29% of treated cases ( P =0.01). Age, gender, and tumor location were comparable in DG+ and DG- groups. For the treatment-naïve group, DG+ tumors were larger with higher tumor grade and stage and more frequent extranodal extension, lymphovascular/perineural invasion, and positive margin. Patients with treated tumors presented at higher disease stages with higher rates of recurrence and metastasis compared with treatment-naïve patients. In this group, DG was also associated with TNM stage and more frequent lymphovascular/perineural spread and positive margin, but not with tumor size, grade, or extranodal extension. In multivariate analysis, in all patients adjusted for tumor size, lymphovascular involvement, margin, T and N stage, metastasis, neoadjuvant therapy status, treatment year, and DG, DG was found to be an independent adverse predictor of survival outcomes in EAC. DG in EAC is associated with adverse clinicopathologic features and worse patient outcomes. DG should be considered throughout the entire clinicopathologic evaluation of treatment-naïve and treated tumors as well as in future staging systems.

Significance of Crypt Atypia in Barrett's Esophagus: A Clinical, Molecular, and Outcome Study.

BACKGROUND & AIMS: The aim of this study was to characterize baseline morphologic features of crypts in nondysplastic Barrett's esophagus and correlate them with DNA content abnormalities and risk of progression to high-grade dysplasia (HGD) or esophageal adenocarcinoma (EAC). METHODS: The morphologic features of nondysplastic crypts in baseline biopsy specimens from 212 BE patients (2956 biopsy specimens) were graded histologically using a 4-point scale (crypt atypia levels, 0-3). DNA content abnormalities were detected using flow cytometry. RESULTS: In patients who had dysplasia in their baseline biopsy specimens, dysplasia was associated significantly with increasing grades of crypt atypia in the background nondysplastic Barrett's esophagus (P < .001). In a subset of patients without dysplasia at baseline (N = 149), a higher grade of crypt atypia was associated with longer Barrett's esophagus segment length (5.5 vs 3.3 cm; P = .0095), and a higher percentage of cells with 4N DNA content (3.67 ± 1.27 vs 2.93 ± 1.22; P = .018). Crypt atypia was associated with the development of any neoplasia (low-grade dysplasia and HGD/EAC). Although no significant association was noted between the grade of crypt atypia and increased 4N, aneuploidy, or progression to HGD/EAC, only patients with grade 2 or 3 crypt atypia showed increased 4N, aneuploidy, or progression to HGD/EAC. CONCLUSIONS: Patients with Barrett's esophagus likely develop dysplasia via a progressive increase in the level of crypt atypia before the onset of dysplasia, and these changes may reflect some alteration of DNA content.

WATS 3D : An Interobserver Study of Barrett's Esophagus-Associated Dysplasia Among Gastrointestinal Pathologists.

INTRODUCTION: Wide-area transepithelial sampling with 3-dimensional computer-assisted analysis (WATS 3D ) has been shown to increase the detection rate of dysplasia (and intestinal metaplasia) in patients with Barrett's esophagus (BE). The purpose of this study was to evaluate the interobserver variability and accuracy of diagnosing BE-associated dysplasia in WATS 3D specimens among gastrointestinal (GI) pathologists without prior experience with this technology. METHODS: Five GI pathologists underwent a 4-hour in-person (at microscope) and virtual training session and then evaluated digital images of discrete cellular foci from 60 WATS 3D cases with BE (20 nondysplastic BE [NDBE], 20 low-grade dysplasia [LGD], and 20 high-grade dysplasia/esophageal adenocarcinoma [HGD/EAC]). Each case consisted of 1 hematoxylin and eosin-stained image (cell block), and 1 liquid cytology or papanicolaou-stained smear image (120 images in total). RESULTS: The overall kappa value among the 5 study pathologists was excellent (overall kappa = 0.93; kappa = 0.93 and 0.97 for cell block and smear specimens, respectively). There were no significant differences noted in kappa values in interpretation of the cell block vs smear specimens or in any of the individual diagnostic categories when the latter were evaluated separately. Furthermore, agreement was perfect (100%) regarding detection of neoplasia (either LGD, HGD, or EAC). Diagnoses were made with complete confidence in 91% of instances. DISCUSSION: We conclude that GI pathologists, without any prior experience in interpretation of WATS 3D specimens, can undergo a short training session and then diagnose these specimens with a very high level of accuracy and reproducibility.

Assessment of vitamin D levels in patients with oral potentially malignant disorders and oral squamous cell carcinoma-A cross-sectional study.

Objectives: The aim of this study was to assess and compare the serum and salivary levels of Vitamin D in patients with oral potentially malignant disorders (OPMD) and Oral squamous cell carcinoma (OSCC) with healthy controls. Method: This cross-sectional study was carried out among 60 patients reporting to the department of Oral Medicine and Radiology, and included patients with OPMDs, OSCC and healthy controls. The Vitamin D levels were estimated using the chemiluminescence immunoassay. One-way ANOVA was used to compare mean and statistical difference between the groups. Tukey's post HOC test calculated for inter group difference. Serum and salivary Vitamin D levels were corelated with Pearson's coefficient. The values of p < 0.005 was considered as significant. Results: The levels of Vitamin D were decreased in study group as compared to controls both in serum and saliva. (p < 0.001). Between serum and salivary Vitamin D levels, a strong association was discovered using the Pearson's coefficient value of 0.737 (p < 0.001). Conclusion: In this study, patients with both OPMDs and OSCC had Vitamin D insufficiency & deficiency. Vitamin D level assessment should be included as a standard component of routine investigations for these individuals.

Artificial intelligence-integrated optical coherence tomography for screening and early detection of oral cancer.

Early detection of oral cancer is essential for improving patient survival rates and leads to higher chances of successful treatment, reduced cost of complex treatments, and improved quality of life of patients. Oral cancer often arises from oral potentially malignant disorders (OPMDs), among which leukoplakia is the most common. Numerous chairside diagnostic aids and imaging modalities have been reviewed for screening detection of OPMDs and oral cancer, but these techniques have limitations. Novel optical diagnostic modalities work on the assumption that neoplastic and dysplastic tissues have different absorbance and reflectance properties when exposed to specific wavelengths of light. Optical coherence tomography (OCT) imaging is a promising new technology in the field of oral oncology. The ability of OCT to provide real-time, nondestructive, high-resolution, radiation-free images makes it an ideal modality for screening and detection of neoplastic changes in the oral mucosa, but interpretation of OCT images requires training and expertise. To overcome this limitation, artificial intelligence-based diagnostic algorithms are being combined with OCT imaging to assist professionals in achieving high-accuracy interpretation of OCT images. This review highlights the applications and scope of artificial intelligence in OCT imaging for the screening and detection of early-stage oral cancer.

Replicative stress in gastroesophageal cancer is associated with chromosomal instability and sensitivity to DNA damage response inhibitors.

Gastroesophageal adenocarcinoma (GEA) is an aggressive malignancy with chromosomal instability (CIN). To understand adaptive responses enabling DNA damage response (DDR) and CIN, we analyzed matched normal, premalignant, and malignant gastric lesions from human specimens and a carcinogen-induced mouse model, observing activation of replication stress, DDR, and p21 in neoplastic progression. In GEA cell lines, expression of DDR markers correlated with ploidy abnormalities, such as number of high-level focal amplifications and whole-genome duplication (WGD). Integrating TP53 status, ploidy abnormalities, and DDR markers into a compositive score helped predict GEA cell lines with enhanced sensitivity to Chk1/2 and Wee1 inhibition, either alone or combined with irinotecan (SN38). We demonstrate that Chk1/2 or Wee1 inhibition combined with SN38/irinotecan shows greater anti-tumor activity in human gastric cancer organoids and an in vivo xenograft mouse model. These findings indicate that specific DDR biomarkers and ploidy abnormalities may predict premalignant progression and response to DDR pathway inhibitors.

Predicting recurrence in pancreatic neuroendocrine tumours: role of ARX and alternative lengthening of telomeres (ALT).

BACKGROUND: While many pancreatic neuroendocrine tumours (PanNET) show indolent behaviour, predicting the biological behaviour of small nonfunctional PanNETs remains a challenge. Nonfunctional PanNETs with an epigenome and transcriptome that resemble islet alpha cells (ARX-positive) are more aggressive than neoplasms that resemble islet beta cells (PDX1-positive). In this study, we explore the ability of immunohistochemistry for ARX and PDX1 and telomere-specific fluorescence in situ hybridisation (FISH) for alternative lengthening of telomeres (ALT) to predict recurrence. METHODS: Two hundred fifty-six patients with PanNETs were identified, and immunohistochemistry for ARX and PDX1 was performed. Positive staining was defined as strong nuclear staining in >5% of tumour cells. FISH for ALT was performed in a subset of cases. RESULTS: ARX reactivity correlated with worse disease-free survival (DFS) (P = 0.011), while there was no correlation between PDX1 reactivity and DFS (P = 0.52). ALT-positive tumours (n = 63, 31.8%) showed a significantly lower DFS (P < 0.0001) than ALT-negative tumours (n = 135, 68.2%). ARX reactivity correlated with ALT positivity (P < 0.0001). Among nonfunctional tumours, recurrence was noted in 18.5% (30/162) of ARX-positive tumours and 7.5% (5/67) of ARX-negative tumours. Among WHO grade 1 and 2 PanNETs with ≤2 cm tumour size, 14% (6/43) of ARX-positive tumours recurred compared to 0 of 33 ARX-negative tumours and 33.3% (3/9) ALT-positive tumours showed recurrence versus 4.4% (2/45) ALT-negative tumours. CONCLUSION: Immunohistochemistry for ARX and ALT FISH status may aid in distinguishing biologically indolent cases from aggressive small low-grade PanNETs, and help to identify patients who may preferentially benefit from surgical intervention.

Multi-centric clinic trials in evidence-based research - A narrative review on the Indian scenario.

Evidence-based health care is gaining prominence since the past many decades. The ultimate goal of evidence-based medicine is providing the best available treatment to patients. The boom in pharmacy sector has seen a rapid rise in randomised controlled clinical trials. Novel medicines or diagnostic tests must be tested before introducing to the target population. Randomised controlled trials are at the top hierarchy of evidence-based health care, especially for testing newly invented drugs. The results obtained from randomised controlled trials cannot be generalised to the entire population. This has led to the evolvement of multi-centre trials in evidence-based research. Multi-centre trials can overcome the barriers associated with single-centre clinical trials. The conduct of multi-centre trials is still in a budding stage in India. Although there are many ongoing multi-centre trials in India, very few trials are conducted among the dental fraternity. The conduct of such trials has its own set of challenges involving funding, ethical committee approval, and logistic requirements. This paper will discuss the growth of multi-centre research, steps involved in conduct of multi-centre trials, and the challenges faced in conducting these trials by the dental specialists in India.

Immune microenvironment and lymph node yield in colorectal cancer.

BACKGROUND: Lymph node (LN) harvesting is associated with outcomes in colonic cancer. We sought to interrogate whether a distinctive immune milieu of the primary tumour is associated with LN yield. METHODS: A total of 926 treatment-naive patients with colorectal adenocarcinoma with more than 12 LNs (LN-high) were compared with patients with 12 or fewer LNs (LN-low). We performed immunohistochemistry and quantification on tissue microarrays for HLA class I/II proteins, beta-2-microglobulin (B2MG), CD8, CD163, LAG3, PD-L1, FoxP3, and BRAF V600E. RESULTS: The LN-high group was comprised of younger patients, longer resections, larger tumours, right-sided location, and tumours with deficient mismatch repair (dMMR). The tumour microenvironment showed higher CD8+ cells infiltration and B2MG expression on tumour cells in the LN-high group compared to the LN-low group. The estimated mean disease-specific survival was higher in the LN-high group than LN-low group. On multivariate analysis for prognosis, LN yield, CD8+ cells, extramural venous invasion, perineural invasion, and AJCC stage were independent prognostic factors. CONCLUSION: Our findings corroborate that higher LN yield is associated with a survival benefit. LN yield is associated with an immune high microenvironment, suggesting that tumour immune milieu influences the LN yield.

Segmental Arterial Mediolysis Presenting as a Pancreatic Mass in a Pediatric Patient: A Case Report.

We describe a case of segmental arterial mediolysis (SAM) in a 2-year-old male who presented with symptoms of acute pancreatitis. SAM is a vascular entity of unknown etiology that involves medium-sized arteries in which the integrity of the vessel wall is compromised, resulting in increased susceptibility to ischemia, hemorrhage, and dissection. The clinical presentation is variable and can range from abdominal pain to more ominous findings of abdominal hemorrhage or organ infarction. This entity should be considered in the correct clinical setting and after other vasculopathies have been excluded. We aim to bring awareness to pediatric providers given this is a rare entity with variable presentation, which could be potentially life threatening.

Clinical, pathological, genetics and intratumoural immune milieu of micropapillary carcinoma of the colon.

AIM: Micropapillary carcinoma (MPC) is a recognised WHO variant of colonic carcinoma (CC), although little is known about its prognosis, immune microenvironment and molecular alterations. We investigated its clinical, pathological and immunological characteristics. METHODS: We assessed 903 consecutive CCs and used the WHO definition to identify MPC. We recorded serrated and mucinous differentiation and mismatch repair (MMR) status. We performed immunohistochemistry and quantification on tissue microarrays for HLA class I/II proteins, beta-2-microglobulin (B2MG), CD8, CD163, LAG3, PD-L1, FoxP3, PD-L1and BRAF V600E. RESULTS: We classified 8.6% (N=78) of CC as MPC. Relative to non-MPC, MPC was more often high grade (p=0.03) and showed serrated morphology (p<0.01); however, we found no association with extramural venous invasion (p=0.41) and American Joint Committee on Cancer stage (p=0.95). MPCs showed lower numbers of CD8 positive lymphocytes (p<0.01), lower tumour cell B2MG expression (p=0.04) and lower tumour cell PD-L1 expression (p<0.01). There was no difference in HLA class I/II, LAG3, FOXP3, CD163 and PD-L1 positive histiocytes. There was no association with MMR status or BRAF V600E relative to non-MPC. MPC was not associated with decreased disease-specific survival (p=0.36). CONCLUSION: MPCs are associated with high-grade differentiation and a less active immune microenvironment than non-MPC. MPC is not associated with inferior disease-specific survival.

Replicative stress in gastroesophageal adenocarcinoma is associated with chromosomal instability and sensitivity to DNA damage response inhibitors.

Gastroesophageal adenocarcinoma (GEA) is an aggressive, often lethal, malignancy that displays marked chromosomal instability (CIN). To understand adaptive responses that enable CIN, we analyzed paired normal, premalignant, and malignant gastric lesions from human specimens and a carcinogen-induced mouse model, observing activation of replication stress, DNA damage response (DDR), and cell cycle regulator p21 in neoplastic progression. In GEA cell lines, expression of DDR markers correlated with ploidy abnormalities, including high-level focal amplifications and whole-genome duplication (WGD). Moreover, high expression of DNA damage marker H2AX correlated with CIN, WGD, and inferior patient survival. By developing and implementing a composite diagnostic score that incorporates TP53 mutation status, ploidy abnormalities, and H2AX expression, among other genomic information, we can identify GEA cell lines with enhanced sensitivity to DDR pathway inhibitors targeting Chk1/2 and Wee1. Anti-tumor properties were further augmented in combination with irinotecan (SN38) but not gemcitabine chemotherapy. These results implicate specific DDR biomarkers and ploidy abnormalities as diagnostic proxy that may predict premalignant progression and response to DDR pathway inhibitors.

Quantitative p53 immunostaining aids in the detection of prevalent dysplasia.

AIMS: The lack of accepted scoring criteria has precluded the use of p53 in routine practice. We evaluate the utility of automated quantitative p53 analysis in risk stratifying Barrett's oesophagus (BE) patients using non-dysplastic BE (NDBE) biopsies in a multicentric cohort of BE progressor (P) and non-progressor (NP) patients. METHODS: NDBE biopsies prior to the diagnosis of advanced neoplasia from 75 BE-P, and index and last surveillance biopsies from 148 BE-NP were stained for p53, and scored digitally as 1+, 2+ and 3+. A secondary cohort of 30 BE-P was evaluated. RESULTS: Compared with BE-NP, BE-P was predominantly men (p=0.001), ≥55 years of age (p=0.008), with longer BE segments (71% vs 33%; p<0.001). The mean number of 3+p53 positive cells and 3+ positive glands were significantly more in BE-P versus BE-NP NDBE biopsies (175 vs 9.7, p<0.001; 9.8 vs 0.1; p<0.001, respectively). At a cut-off of ≥10 p53 (3+) positive cells, the sensitivity and specificity of the assay to identify BE-P were 39% and 93%. On multivariate analysis, scoring p53 in NDBE biopsies, age, gender and length of BE were significantly associated with neoplastic progression. 54% of patients classified as prevalent dysplasia showed an abnormal p53 immunohistochemical stain. These findings were validated in the secondary cohort. CONCLUSIONS: Automated p53 analysis in NDBE biopsies serves as a promising tool for assessing BE neoplastic progression and risk stratification. Our study highlights the practical applicability of p53 assay to routine surveillance practice and its ability to detect prevalent dysplasia.

Defining an abnormal p53 immunohistochemical stain in Barrett's oesophagus-related dysplasia: a single-positive crypt is a sensitive and specific marker of dysplasia.

AIMS: p53 is an independent risk stratification marker in Barrett's oesophagus (BE), but no universally accepted definition exists for abnormal p53 staining. Herein, we assess p53 stains in two cohorts to: (1) define abnormal p53 staining in BE-related dysplasia (BERD) and (2) assess the specificity and sensitivity of this cut-point for the diagnosis of dysplasia. METHODS: Cohort 1 (n = 313) included (1) dysplastic BE biopsies, (2) prior non-dysplastic BE (NDBE) biopsies from the same patients and (3) NDBE biopsies from patients who never progressed to dysplasia. Cohort 2 (n = 191) consisted of BE biopsies in which p53 staining aided in diagnosing dysplasia. Automated p53 staining quantification was performed on cohort 1. A semiquantitative p53 analysis, performed on both cohorts, included: (1) number of strongly positive glands, (2) strong glandular surface staining, (3) percentage of strongly positive glands and (4) null phenotype. RESULTS: NDBE biopsies from cohort 1 patients who progressed to dysplasia were more likely to show p53 positivity than non-progressors (16.9 versus 0.6%) (P = 0.0001). The optimal quantitative cut-point for distinguishing dysplastic from never-dysplasia biopsies was 10 strongly positive cells. By semiquantitative analysis, a single strongly p53-positive gland distinguished dysplastic from never-dysplasia BE (sensitivity 98.6%, specificity 99.4%). The semiquantitative and quantitative analyses correlated (P = 0.0001). In cohort 2, the sensitivity and specificity for BERD of ≥ 1 strongly positive p53 gland were 86.0 and 88.6%. CONCLUSIONS: A single strongly positive p53 gland is sensitive and specific for BERD. Automated p53 analysis may reduce subjectivity associated with the diagnosis of BERD.