Irshad Soomro

AIMS: The Vienna classification is used to classify dysplasia in Barrett's oesophagus (BO), but reproducibility and value of diagnosis of lower grades in particular are often questioned. The aim was to test the diagnostic variability and correlation with patient outcome and to attempt to define histological features causing discrepant diagnoses, as well as to test the impact of adding p53 immunohistochemistry on reproducibility and prediction of outcome. METHODS AND RESULTS: One hundred and forty-three patients with 154 sets of biopsy specimens originally diagnosed with Barrett's dysplasia were retrieved from the pathology records of Nottingham University Hospital. Thirty-two Barrett's patients without dysplasia were added. Anonymized slides were graded independently by five pathologists without and with p53-stained slides. Interobserver variation, correlation with outcome and diagnostic accuracy were determined. Weighted kappa scores between pairs of pathologists showed substantial agreement and improved after p53 immunohistochemistry. Agreement with the original diagnosis was substantially lower. Fourteen of 34 low-grade dysplasias (LGD) and 27 of 30 high-grade dysplasias on consensus progressed within 10 years compared with 18/94 and 28/39 of original diagnoses. Progression correlated with p53 positivity. CONCLUSION: The Vienna classification is useful and reproducible in BO. Consensus diagnosis by gastrointestinal pathologists produces high specificity and predictive value, even for LGD. p53 immunohistochemistry assists in diagnosis in difficult cases and predicts progression.

BACKGROUND: Altered DNA repair may be associated with aggressive tumour biology and impact upon response to chemotherapy and radiotherapy. We investigated whether expression of human AP endonuclease (APE1), a key multifunctional protein involved in DNA BER, would impact on clinicopathological outcomes in ovarian, gastro-oesophageal, and pancreatico-biliary cancer. METHODS: Formalin-fixed human ovarian, gastro-oesophageal, and pancreatico-biliary cancers were constructed into TMAs. Expression of APE1 was analysed by IHC and correlated to clinicopathological variables. RESULTS: In ovarian cancer, nuclear APE1 expression was seen in 71.9% (97 out of 135) of tumours and correlated with tumour type (P=0.006), optimal debulking (P=0.009), and overall survival (P=0.05). In gastro-oesophageal cancers previously exposed to neoadjuvant chemotherapy, 34.8% (16 out of 46) of tumours were positive in the nucleus and this correlated with shorter overall survival (P=0.005), whereas cytoplasmic localisation correlated with tumour dedifferentiation (P=0.034). In pancreatico-biliary cancer, nuclear staining was seen in 44% (32 out of 72) of tumours. Absence of cytoplasmic staining was associated with perineural invasion (P=0.007), vascular invasion (P=0.05), and poorly differentiated tumours (P=0.068). A trend was noticed with advanced stage (P=0.077). CONCLUSIONS: Positive clinicopathological correlations of APE1 expression suggest that APE1 is a potential drug target in ovarian, gastro-oesophageal, and pancreatico-biliary cancers.

BACKGROUND: This multicentre cohort study sought to define a robust pathological indicator of clinically meaningful response to neoadjuvant chemotherapy in oesophageal adenocarcinoma. METHODS: A questionnaire was distributed to 11 UK upper gastrointestinal cancer centres to determine the use of assessment of response to neoadjuvant chemotherapy. Records of consecutive patients undergoing oesophagogastric resection at seven centres between January 2000 and December 2013 were reviewed. Pathological response to neoadjuvant chemotherapy was assessed using the Mandard Tumour Regression Grade (TRG) and lymph node downstaging. RESULTS: TRG (8 of 11 centres) was the most widely used system to assess response to neoadjuvant chemotherapy, but there was discordance on how it was used in practice. Of 1392 patients, 1293 had TRG assessment; data were available for clinical and pathological nodal status (cN and pN) in 981 patients, and TRG, cN and pN in 885. There was a significant difference in survival between responders (TRG 1-2; median overall survival (OS) not reached) and non-responders (TRG 3-5; median OS 2·22 (95 per cent c.i. 1·94 to 2·51) years; P < 0·001); the hazard ratio was 2·46 (95 per cent c.i. 1·22 to 4·95; P = 0·012). Among local non-responders, the presence of lymph node downstaging was associated with significantly improved OS compared with that of patients without lymph node downstaging (median OS not reached versus 1·92 (1·68 to 2·16) years; P < 0·001). CONCLUSION: A clinically meaningful local response to neoadjuvant chemotherapy was restricted to the small minority of patients (14·8 per cent) with TRG 1-2. Among local non-responders, a subset of patients (21·3 per cent) derived benefit from neoadjuvant chemotherapy by lymph node downstaging and their survival mirrored that of local responders.