Endoscopic Ultrasonography for Staging of Esophageal Cancer in a Non-Expert Center

Abstract

Background: It is not known whether the annual volume of endoscopic ultrasonography (EUS) affects the results of staging of esophageal cancer. We compared EUS in the evaluation of invasion (T-stage), and regional (N-stage) and celiac (M-stage) lymph nodes in a high-volume center for esophageal cancer (>100 cases/year), but non-expert center for EUS (<50 EUS/endoscopist/yr.), with reported results from 5 expert centers (>50 EUS/endoscopist/yr.). Methods: Between 1994-2003, 761 patients underwent EUS without fine-needle aspiration (FNA) or measures to pass a stenotic tumor. EUS was performed by 4 endoscopists in the non-expert center. There was no difference in performance over time or between the 4 endoscopists. Resection was performed in 244 patients with post-operative TNM-stage as gold standard. In expert centers, 670 patients underwent EUS, if indicated with dilation or a small-caliber probe, and post-operative TNM-stage and/or FNA as gold standard. Results: In 71 (29%) patients, the EUS probe could not pass the stricture. The sensitivity to distinguish T3 from other T-stages was 85% (75/88) and 79% (49/62), with a specificity of 57% (48/85) and 11% (1/9), with or without passage of the EUS probe, resp. In expert centers, slightly higher sensitivities (88-94%) and higher specificities (75-90%) were reported. The sensitivity of EUS to distinguish T4 from other T-stages was 0% (0/2) and 0% (0/3), with a specificity of 99% (170/171) and 97% (66/68), with or without passage, resp. In expert centers, higher sensitivities (67-95%) and comparable specificities (95-99%) were reported. The sensitivity for regional lymph nodes was 45% (42/94) and 32% (14/44), with a specificity of 75% (58/77) and 91% (19/21), with or without passage, resp. In expert centers, higher sensitivities (63-89%) and comparable specificities (75-82%) were reported. The sensitivity for celiac lymph nodes was 19% (3/16) and 11% (1/9), with a specificity of 99.4% (154/155) and 100% (56/56), with or without passage, resp. In expert centers, higher sensitivities (72-83%) and comparable specificities (85-100%) were reported. Conclusions: The results of EUS, without measures to pass a stenotic tumor and/or FNA, and performed in a non-expert center compared unfavorably with those obtained in expert centers. Our results suggest that preoperative staging by EUS should be centralized and performed by few, dedicated endoscopists, in high-volume centers, to optimize staging of esophageal cancer.