Impact of 18FFDG-PET/CT and Laparoscopy in Staging of Locally Advanced Gastric Cancer: A Cost Analysis in the Prospective Multicenter PLASTIC-Study.

BACKGROUND: Unnecessary D2-gastrectomy and associated costs can be prevented after detecting non-curable gastric cancer, but impact of staging on treatment costs is unclear. This study determined the cost impact of 18F-fluorodeoxyglucose positron emission tomography/computed tomography (18FFDG-PET/CT) and staging laparoscopy (SL) in gastric cancer staging. MATERIALS AND METHODS: In this cost analysis, four staging strategies were modeled in a decision tree: (1) 18FFDG-PET/CT first, then SL, (2) SL only, (3) 18FFDG-PET/CT only, and (4) neither SL nor 18FFDG-PET/CT. Costs were assessed on the basis of the prospective PLASTIC-study, which evaluated adding 18FFDG-PET/CT and SL to staging advanced gastric cancer (cT3-4 and/or cN+) in 18 Dutch hospitals. The Dutch Healthcare Authority provided 18FFDG-PET/CT unit costs. SL unit costs were calculated bottom-up. Gastrectomy-associated costs were collected with hospital claim data until 30 days postoperatively. Uncertainty was assessed in a probabilistic sensitivity analysis (1000 iterations). RESULTS: 18FFDG-PET/CT costs were €1104 including biopsy/cytology. Bottom-up calculations totaled €1537 per SL. D2-gastrectomy costs were €19,308. Total costs per patient were €18,137 for strategy 1, €17,079 for strategy 2, and €19,805 for strategy 3. If all patients undergo gastrectomy, total costs were €18,959 per patient (strategy 4). Performing SL only reduced costs by €1880 per patient. Adding 18FFDG-PET/CT to SL increased costs by €1058 per patient; IQR €870-1253 in the sensitivity analysis. CONCLUSIONS: For advanced gastric cancer, performing SL resulted in substantial cost savings by reducing unnecessary gastrectomies. In contrast, routine 18FFDG-PET/CT increased costs without substantially reducing unnecessary gastrectomies, and is not recommended due to limited impact with major costs. TRIAL REGISTRATION: NCT03208621. This trial was registered prospectively on 30-06-2017.

Diagnostic variability in the histopathological assessment of advanced colorectal adenomas and early colorectal cancer in a screening population.

AIM: The aim of this study was to evaluate interobserver variability between individual pathologists and a panel of pathologists in the histopathological assessment of advanced colorectal neoplasms in the Dutch bowel cancer screening population. METHODS AND RESULTS: Histological slides of adenomas with high-grade dysplasia and early colorectal carcinomas (CRC) from 20 different laboratories were reviewed by the pathology panel of the Dutch bowel screening programme. Interobserver variability was reported by descriptive statistics. In addition, potential clinical consequences of discrepancies were evaluated. A total of 104 cases of adenomas with high-grade dysplasia and 83 early CRCs were reviewed. Discrepancies were observed in 41 of 104 (39.4%) adenoma cases, which potentially had clinical consequences in 16 (15.4%) cases. For CRC, discrepancies were shown in 44 of 83 cases (53.0%) and would have potentially led to alternative treatment strategies in 25 (30.1%) cases. Most frequently, discrepancies were observed in the assessment of lymphovascular invasion (23 of 73 cases, 31.5%). CONCLUSION: This study showed that considerable interobserver variability is present in the histopathological assessment of advanced colorectal neoplasia, which may impact upon treatment choices. Additional stains and education, as well as intercollegial consultation, might decrease this variability.

Quantitative assessment of gastric antrum atrophy shows restitution to normal histology after Helicobacter pylori eradication.

BACKGROUND/AIMS: Grading gastric mucosal atrophy in antrum biopsy specimens remains a controversial subject because of limitations in interobserver agreement. We previously described a reliable, quantitative method for grading atrophy of the corpus mucosa with excellent reproducibility and good correlation with the Sydney scores. The aims of the present study were to evaluate the applicability of this method for the grading of antral atrophy and to study the effect of Helicobacter pylori eradication on the antral mucosa. METHODS: Antrum biopsy specimens were collected from 71 gastroesophageal reflux disease patients at baseline and after 3 and 12 months. After the first endoscopy, all subjects were treated with omeprazole 40 mg daily for 12 months. After randomization, 27 of the 48 H. pylori-positive patients additionally received eradication therapy. In 182 hematoxylin-eosin-stained specimens, which were of sufficient quality, the proportions (volume percentages) of glands (VPGL), stroma (VPS), infiltrate (VPI), and intestinal metaplasia in the glandular zone of the antrum mucosa were measured using a point-counting method. In these specimens, mucosal atrophy was assessed by two experienced gastrointestinal tract pathologists (E.B. and J.L.) according to the updated Sydney classification as either nonatrophic mucosa (n = 47) or as mild (n = 29), moderate (n = 50), or marked (n = 56) atrophy. In addition, a group of 23 cases with difficult-to-classify grades of atrophy were included. RESULTS: The mean VPGL decreased with increasing Sydney grades of atrophy (p < 0.001), while the mean VPS and VPI increased (both p < 0.001). After H. pylori eradication, even the cases with the lowest VPGL regressed to normal levels. CONCLUSIONS: Overall, a low VPGL correlates with increasing grades of antrum mucosal atrophy. The present data indicate that gastric mucosal atrophy is reversible, since almost all cases showed regression of VPGL after H. pylori eradication. The cases with difficult-to-classify grades of atrophy showed significantly lower VPGLs and higher VPIs than the reference cases.