Salivary metabolomic biomarkers for esophageal and gastric cancers by liquid chromatography-mass spectrometry.

Early detection of esophageal and gastric cancers is essential for patients' prognosis; however, optimal noninvasive screening tests are currently not available. Saliva is a biofluid that is readily available, allowing for frequent screening tests. Thus, we explored salivary diagnostic biomarkers for esophageal and gastric cancers using metabolomic analyses. Saliva samples were collected from patients with esophageal (n = 50) and gastric cancer (n = 63), and patients without cancer as controls (n = 20). Salivary metabolites were analyzed by liquid chromatography-mass spectrometry to identify salivary biomarkers. We also examined the metabolic profiles of gastric cancer tissues and compared them with the salivary biomarkers. The sensitivity of the diagnostic models based on salivary biomarkers was assessed by comparing it with that of serum tumor markers. Additionally, using postoperative saliva samples collected from patients with gastric cancer, we analyzed the changes in the biomarkers' concentrations before and after surgery. Cytosine was detected as a salivary biomarker for gastric cancer, and cytosine, 2-oxoglutarate, and arginine were detected as salivary biomarkers for esophageal cancer. Cytidine, a cytosine nucleotide, showed decreased concentrations in gastric cancer tissues. The sensitivity of the diagnostic models for esophageal and gastric cancers was 66.0% and 47.6%, respectively, while that of serum tumor markers was 40%. Salivary cytosine concentration increased significantly postoperatively relative to the preoperative value. In summary, we identified salivary biomarkers for esophageal and gastric cancers, which showed diagnostic sensitivity at least comparable to that of serum tumor markers. Salivary metabolomic tests could be promising screening tests for these types of cancer.

Percent vital capacity predicts postoperative sarcopenia after esophagectomy in initially nonsarcopenic esophageal cancer patients: a retrospective cohort study.

PURPOSE: The development of sarcopenia after esophagectomy is reported to affect the outcomes of patients with esophageal cancer (EC); however, the characteristics of patients likely to be predisposed to postoperative sarcopenia have not been defined. This study explores the associations between preoperative respiratory function and surgery-induced sarcopenia in EC patients confirmed as nonsarcopenic preoperatively. METHODS: The subjects of this retrospective review were 128 nonsarcopenic patients who underwent esophagectomy for EC. We took body composition measurements and performed physical function tests 3 and 6 months postoperatively, to establish whether sarcopenia was present, according to the 2019 Asian Working Group for Sarcopenia guideline. We defined patients with surgery-induced sarcopenia as those with evidence of the development of sarcopenia within 6 months postoperatively or those with documented sarcopenia at 3 months but who could not be evaluated at 6 months. RESULTS: Surgery-induced sarcopenia developed in 19 of the 128 patients (14.8%), which correlated significantly with the preoperative %VC value (p < 0.01), but not with the preoperative FEV1.0% value. We set the lower quartile %VC value (91%) as the cut-off for predicting surgery-induced sarcopenia. A low %VC was independently associated with surgery-induced sarcopenia (odds ratio: 5.74; 95% confidence interval: 1.99-16.57; p < 0.01). CONCLUSIONS: Based on the findings of this study, %VC was a simple but valuable factor for predicting sarcopenia induced by esophagectomy.

Detection of secondary upper gastrointestinal tract cancer during follow-up esophagogastroduodenoscopy after gastrectomy for gastric cancer.

Aim: Esophagogastroduodenoscopy (EGD) may contribute to early detection of secondary cancer in the upper gastrointestinal tract although the clinical relevance of follow-up after gastrectomy remains unclear. This study aimed to elucidate the effectiveness of follow-up EGD by investigating the incidence of secondary cancer in any part of the upper gastrointestinal tract. Methods: Data from 1438 patients who underwent curative partial gastrectomy for primary gastric cancer between 2008 and 2014 and follow-up EGD at least once during a 5-year follow-up period were retrospectively reviewed. Incidence rates of remnant gastric cancer, laryngeal cancer, and esophageal cancer detected after follow-up EGD were determined, and risk factors for secondary cancers were examined. The characteristics of clinicopathological diagnoses of secondary cancers were reviewed and compared according to the frequency of follow-up EGD. Results: The average annual frequency of EGD was 0.7, while the 5-year cumulative incidence rates of remnant gastric cancer and secondary laryngeal and esophageal cancers were 2.9% and 1.3%, respectively. Risk factors for remnant gastric cancer included heavy smoking, proximal gastrectomy, and tumor size ≥ 30 mm. All secondary cancers were resectable upon diagnosis, with endoscopically resectable cancer accounting for 81.0% of cases. Our results found a significantly higher proportion of endoscopically resectable cancers during regular follow-up than during infrequent follow-up. Conclusions: Follow-up EGD can be a useful modality for detecting secondary upper gastrointestinal tract cancer, likely leading to curative treatment for secondary cancer. Focusing on patients presenting with risk factors may increase the value of follow-up EGD after gastrectomy.