Ian F. Yusoff

A Cohort Study of Missed and New Cancers After Esophagogastroduodenoscopy

OBJECTIVES:Little is known about missed rates of upper gastrointestinal cancer (UGC) in Western populations, with most data originating from Japanese centers quoting high missed rates of 23.5–25.8%. The objective of this study was to better define missed rates of esophagogastroduodenoscopy (EGD) and the natural history of UGC in a Western population that underwent an initial EGD without cancer, but were subsequently diagnosed with a UGC. Our hypothesis was that a normal EGD rarely misses the detection of UGC.METHODS:This is a retrospective cohort study. A prospectively maintained electronic database was used to identify all patients who underwent EGD between 1990 and 2004 at the study institution. Patients in this cohort who were diagnosed with UGC before 2006 were identified through the Western Australian Cancer Registry. We defined missed cancers as those diagnosed within 1 year of EGD, possible missed cancers as those diagnosed 1–3 years after EGD, and new cancers as those diagnosed more than 3 years after EGD. This study had no interventions and was conducted at a tertiary referral center. The main outcome measurement included UGC.RESULTS:Of the 28,064 EGDs performed, UGC was diagnosed subsequent to the procedure in 116 cases (0.41%). There were 29 missed cancers, 26 possible missed cancers, and 75 new cancers. Of the missed cancers, 11 were esophageal, 15 were gastric, and 3 were duodenal. In 69% (n=20) of the missed cancers, an abnormality was described at the site of malignancy. In 59% (n=17) of the missed cancers, the indication for EGD was an alarm symptom of dysphagia or suspected blood loss. In an univariate analysis, the presence of an alarm symptom was related to missed cancers, whereas operator experience, trainee participation, and usage of newer equipment were not. One of the main limitations of this study is that it was a retrospective review.CONCLUSIONS:UGC is rare after normal EGD, confirming the high accuracy of EGD. Institutional approval was granted for the conduct of this study.

Detection of hypoxia with 18F-fluoromisonidazole (18F-FMISO) PET/CT in suspected or proven pancreatic cancer.

Purpose of the Report Pancreatic carcinoma is known to demonstrate molecular features of hypoxia. The aim of this prospective pilot study is to analyze the hypoxia agent fluoromisonidazole (FMISO) using PET/CT in pancreatic carcinoma and to compare FMISO activity with glucose metabolism reflected by FDG. Patients and Methods Ten patients with pancreatic carcinoma underwent FMISO and FDG PET scans. FMISO and FDG PET/CT scans were analyzed by 2 PET physicians. Regions of interest drawn on the FDG images were transposed to the FMISO images after study coregistration. The FDG SUVmax was used to quantify metabolic activity and FMISO SUVmax and tumor-to-background (muscle) ratio to quantify hypoxia. Results Seven patients were diagnosed with pancreatic adenocarcinoma. The remaining patients had a neuroendocrine tumor, poorly differentiated/sarcomatoid carcinoma, and mucinous neoplasm. Visual analysis demonstrated increased FMISO activity in 2 pancreatic adenocarcinomas. All patients, however, had increased FDG activity at the tumor site. Mean FDG SUVmax was 6 (range: 3.8 to 9.5) compared to 2.3 for FMISO (range: 1 to 3.4). The 2 positive studies on visual analysis of FMISO did not correspond to the largest tumors, the studies with the highest FMISO or FDG SUVmax. There was no significant correlation between FMISO and FDG SUVmax values. Conclusions The hypoxia imaging agent, FMISO, demonstrates minimal activity in pancreatic tumors. If FMISO PET/CT is to be included in clinical trial protocols of hypoxia in pancreatic cancer, it would require correlation with other imaging modalities to localize the tumor and allow semiquantitative analysis.

Optimizing the multimodal approach to pancreatic cyst fluid diagnosis developing a volume-based triage protocol

The objective of this study was to develop a triage algorithm to optimize diagnostic yield from cytology, carcinoembryonic antigen (CEA), and v‐Ki‐ras2 Kirsten rat sarcoma viral oncogene homolog (KRAS) testing on different components of a single pancreatic cyst fluid specimen. The authors also sought to determine whether cell block supernatant was suitable for CEA and KRAS testing.

Gastric intraepithelial neoplasia in a Western population

Background and study aims Descriptions of the natural history and endoscopic appearances of gastric dysplasia/intraepithelial neoplasia (IEN) that originate mainly from Europe. Currently, there are no Australian data available. We aimed to document endoscopic appearances and progression rates of gastric IEN and to determine the significance of indefinite for IEN. Patients and methods This is a retrospective study, in which cases diagnosed with gastric IEN were identified between 2000 and 2009. Endoscopic appearances, progression rates to more advanced IEN or cancer, and long-term outcomes were recorded. Results A total of 160 cases with IEN (26.9% high grade, 57.5% low grade, 15.6% indefinite) were identified. The mean age was 67.8 years and 53.8% were men. Endoscopic lesions were polypoid in 29.4% and nonpolypoid in 70.6%. The most common location was the antrum (58.7%). Forty patients had an intervention and 76 underwent endoscopic follow-up only. Twenty-two cancers were diagnosed; three who had an intervention were diagnosed within 12 months, one with low-grade intraepithelial neoplasia developing a cancer after 9.9 years, and 13 undergoing surveillance only, were diagnosed with cancer within 12 months of index endoscopy. Five cases had cancer after a mean of 2.6 years. Forty-seven cases initially labelled as indefinite; following rereview 25 remained unchanged, 11 reclassified as negative for IEN, 10 as low grade, and one as high grade. Three of these cases developed cancer over the study period. Conclusion We concluded that (a) majority of gastric IEN are associated with endoscopic lesions, (b) high rate of early cancer diagnosis was observed (c) rates of progression to cancer were lower than reported rates, and (d) indefinite for IEN is not innocuous requiring an expert pathologists review.

Survey of consent practices for inpatient colonoscopy and endoscopic retrograde cholangiopancreatography at a tertiary referral center

Background:  The purpose of the present paper was to determine informed consent practices for inpatient, open‐access colonoscopy and endoscopic retrograde cholangiopancreatography (ERCP) at a tertiary referral center.

A Population Based Study of Gastric Dysplasia in a Western Population

higher in GC tissue, but lower in plasma than those of CSG; and they restored towards normal in plasma after surgery removal. GC/TOFMS data was analyzed using principal component analysis (PCA), partial least squares projection to latent structures and discriminant analysis (PLS-DA).An overview of the data set produced with PCA showed the complete separation of the tissue samples and plasma samples (Figure S-2a). The tissue samples showed larger variations between the GC and CSG patients than did the plasma samples (Figure S-2b). To characterize the metabolic phenotypes of the GC plasma and the postoperative GC plasma relative to the CSG plasma control, a PLS-DA model was calculated (Figure S-2c). CONCLUSION: In tissue of the GC patients, amino acids turn-over, glycolysis, lipid and TCA metabolism were up-regulated while the intermediates level were lower in plasma of GC patients than those in CSG. Surgery removal of GC tissue restored the metabolites level towards normal. The metabolites involved in above metabolism were suggested as the potential markers of GC and had the potential to be alternative diagnostic indicators.

4479 Is routine mucosal biopsy of value in patients with diarrhoea and normal colonoscopy in an open access setting

BACKGROUND: Routine mucosal biopsy in patients undergoing colonoscopy for diarrhoea, in whom macroscopic examination is normal, remains controversial and practice varies widely without clear guidelines. Reported rates of clinically significant microscopic abnormalities vary from 2-27%.It is unclear if ileal biopsy adds anything to colonic biopsy alone. OBJECTIVES: We sought to evaluate the diagnostic yield of colonic and ileal mucosal biopsy in patients undergoing colonoscopy for diarrhoea in whom the macroscopic examination was normal. METHODS: We retrospectively reviewed all colonoscopies performed over a nine year period in a tertiary referral centre with an open access endoscopy service. Cases were selected where the sole indication for colonoscopy was diarrhoea, the musosa was macroscopically normal (other than diverticulosis) and biopsies were performed. Cases were excluded if the examination was inadequate. The histopathology reports of the selected cases were then reviewed. RESULTS: 362 cases were identified. Colonoscopy and biopsy was normal in 260 patients.Ileal biopsies were performed (in addition to colonic biopsies) in 158 cases, none of which revealed clinically significant abnormalities. Clinically significant histological findings were present in 18 cases (5%). Findings included collagenous colitis (5 cases), lymphocytic colitis (1 case), possible lymphocytic colitis (1 case), possible collagenous colitis (1 case), inflammatory bowel disease (2 cases), melanosis coli (2 cases) and significant eosinophil mucosal infiltration (6 cases). 28 patients (8%) had minor histological abnormalities with no specific diagnostic features. The diagnostic yield was highest in patients above 60 years old, where 10% had clinically significant histological abnormalities. All patients with collagenous colitis were female and only 1 was less than 60 years old. CONCLUSIONS: When colonoscopy is normal in patients with diarrhoea, routine colonic biopsy identifies significant pathology in 5% of cases. The diagnostic yield is highest in patients over 60 years old. Routine ileal biopsy is unhelpful.