Detection of Anastomotic Leaks Following Esophagectomy with Cervical Anastomosis Using Drain Fluid Amylase Testing: A Retrospective Study in Taiwan.

Background: Anastomotic leak at the cervical anastomosis following esophagectomy remains a significant problem. However, diagnostic accuracy for this condition is limited, and interpretation varies. This study aimed to share our institution's experience regarding the diagnostic value of esophagram and drain fluid amylase testing. Methods: We retrospectively reviewed patients with esophageal cancer who underwent McKeown esophagectomy. Esophagram was scheduled on postoperative day (POD) 7. Drain fluid amylase levels were measured twice, on POD 3 and POD 7. Diagnostic criteria were established based on the values measured at these time points and the relationship between them. Results: Overall, 103 patients were eligible for evaluation. Of these, 48 underwent drain fluid amylase testing, 67 underwent esophagram, and 12 received both examinations. The sensitivity and specificity of esophagram for detecting anastomotic leak were 28.6% and 95%, respectively. The positive predictive value, negative predictive value, and diagnostic accuracy were 40.0%, 91.9%, and 88.1%, respectively. Among patients who underwent drain fluid amylase testing, the criteria for detecting leaks were defined as follows: (1) an increasing trend (i.e., an amylase level higher on POD 7 than on POD 3) and (2) an amylase level >80 IU/L on POD 7. The sensitivity and specificity of these criteria were 75% and 96.5%, respectively, while the positive and negative predictive values were 75% and 96.5%. The diagnostic accuracy was 93.9%. Conclusion: Compared with esophagram, drain fluid amylase testing is easier to perform and may represent a more accurate method for predicting anastomotic leak.