Treatment for gastric ‘indefinite for neoplasm/dysplasia' lesions based on predictive factors

BACKGROUND Gastric ‘indefinite for neoplasm/dysplasia'(IFND) is a borderline lesion that is difficult to diagnose as either regenerative or neoplastic. There is a need for guidance in the identification of a subset of patients, who have an IFND lesion with a higher risk of malignant potential, to enable risk stratification and optimal management.AIM To determine the clinical and pathologic factors for the accurate diagnosis of gastric IFND lesions.METHODS In total, 461 gastric lesions diagnosed via biopsy as IFND lesions were retrospectively evaluated. Endoscopic resection(n = 134), surgery(n = 22), and follow-up endoscopic biopsy(n = 305) were performed to confirm the diagnosis.The time interval from initial biopsy to cancer diagnosis was measured, and diagnostic delays were categorized as > 2 wk, > 2 mo, > 6 mo, and > 1 year. The IFND lesions presenting as regenerating atypia(60%) or atypical epithelia(40%)at initial biopsy were adenocarcinomas in 22.6%, adenomas in 8.9%, and gastritis in 68.5% of the cases.RESULTS Four clinical factors [age ≥ 60 years(2.445, 95%CI: 1.305-4.580, P = 0.005),endoscopic size ≥ 10 mm(3.519, 95%CI: 1.891-6.548, P < 0.001), single lesion(5.702, 95%CI: 2.212-14.696, P < 0.001), and spontaneous bleeding(4.056, 95%CI:1.792-9.180, P = 0.001)], and two pathologic factors [atypical epithelium(25.575,95%CI: 11.537-56.695, P < 0.001], and repeated IFND diagnosis [6.022, 95%CI:1.822-19.909, P = 0.003)] were independent risk factors for gastric cancer. With two or more clinical factors, the sensitivity and specificity for carcinoma were91.3% and 54.9%, respectively. Ten undifferentiated carcinomas were initially diagnosed as IFND. In the subgroup analysis, fold change(5.594, 95%CI: 1.458-21.462, P = 0.012) predicted undifferentiated or invasive carcinoma in the submucosal layers or deeper. Diagnostic delays shorter than 1 year were not associated with worse prognoses. Extremely well-differentiated adenocarcinomas accounted for half of the repeated IFND cases and resulted in low diagnostic accuracy even on retrospective blinded review.CONCLUSION More than two clinical and pathologic factors each had significant cut-off values for gastric carcinoma diagnosis; in such cases, endoscopic resection should be considered.

Lymphovascular invasion in more than one-quarter of small rectal neuroendocrine tumors

AIM To identify the frequency, clinicopathological risk factors, and prognostic significance of lymphovascular invasion(LVI) in endoscopically resected small rectal neuroendocrine tumors(NETs).METHODS Between June 2005 and December 2015, 104 cases of endoscopically resected small(≤ 1 cm) rectal NET specimens at Hallym University Sacred Heart Hospital in Korea were retrospectively evaluated. We compared the detected rate of LVI in small rectal NET specimens by two methods: hematoxylin and eosin(H&E) and ancillary immunohistochemical staining(D2-40 and Elastica van Gieson); in addition, LVI detection ratedifference between endoscopic procedures were also evaluated. Patient characteristics, prognosis and endoscopic resection results were reviewed by medical charts.RESULTS We observed LVI rates of 25.0% and 27.9% through H&E and ancillary immunohistochemical staining. The concordance rate between H&E and ancillary studies was 81.7% for detection of LVI, which showed statistically strong agreement between two methods(κ = 0.531, P < 0.001). Two endoscopic methods were studied, including endoscopic submucosal resection with a ligation device and endoscopic submucosal dissection, and no statistically significant difference in the LVI detection rate was detected between the two(26.3% and 26.8%, P = 0.955). LVI was associated with large tumor size(> 5 mm, P = 0.007), tumor grade 2(P = 0.006). Among those factors, tumor grade 2 was the only independent predictive factor for the presence of LVI(HR = 4.195, 95%CI: 1.321-12.692, P = 0.015). No recurrence was observed over 28.8 mo regardless of the presence of LVI.CONCLUSION LVI may be present in a high percentage of small rectal NETs, which may not be associated with short-term prognosis.