Breast cancer detection using volatile compound profiles in exhaled breath via selected ion-flow tube mass spectrometry.

This study aimed to evaluate volatile compounds in exhaled breath as a non-invasive screening method to detect breast neoplasms. Exhaled breath samples were collected from patients with breast cancer (BC;n= 45) and non-breast cancer (NBC;n= 51) controls. Selected ion-flow tube mass spectrometry was used to quantify the volatile compounds. A multiple logistic regression (MLR) model was developed by combining multiple compounds to discriminate between BC and NBC samples. Amongst the 672 quantified peaks, 17 showed significant differences between BC and NBC samples (P< 0.05 corrected by false discovery rate). Pathway analysis revealed a significant difference in glycerophospholipid metabolism. The MLR model showed an area under the receiver operating characteristic curve (AUC) of 0.719 (95% confidence interval: 0.615-0.822,P< 0.0002). Cross-validation under various conditions resulted in a slight fluctuation in the AUC values, indicating the high generalizability of the MLR model. The model showed a higher BC probability for advanced-stage subjects and higher Ki67 (⩾30) for BC subjects. This study suggests the potential of volatile compounds in exhaled breath as a noninvasive screening method for BC.

Establishment of a Quick and Highly Accurate Breath Test for ALDH2 Genotyping.

OBJECTIVES: Acetaldehyde, the first metabolite of ethanol, is a definite carcinogen for the esophagus, head, and neck; and aldehyde dehydrogenase 2 (ALDH2) is a mitochondrial enzyme that catalyzes the metabolism of acetaldehyde. The ALDH2 genotype exists as ALDH2*1/*1 (active ALDH2), ALDH2*1/*2 (heterozygous inactive ALDH2), and ALDH2*2/*2 (homozygous inactive ALDH2). Many epidemiological studies have reported that ALDH2*2 carriers are at high risk for esophageal or head and neck squamous cell carcinomas by habitual drinking. Therefore, identification of ALDH2*2 carriers would be helpful for the prevention of those cancers, but there have been no methods suitable for mass screening to identify these individuals. METHODS: One hundred and eleven healthy volunteers (ALDH2*1/*1 carriers: 53; ALDH2*1/*2 carriers: 48; and ALDH2*2/*2 carriers: 10) were recruited. Breath samples were collected after drinking 100 ml of 0.5% ethanol using specially designed gas bags, and breath ethanol and acetaldehyde levels were measured by semiconductor gas chromatography. RESULTS: The median (range) breath acetaldehyde levels at 1 min after alcohol ingestion were 96.1 (18.1-399.0) parts per billion (p.p.b.) for the ALDH2*1/*1 genotype, 333.5 (78.4-1218.4) p.p.b. for the ALDH2*1/*2 genotype, and 537.1 (213.2-1353.8) p.p.b. for the ALDH2*2/*2 genotype. The breath acetaldehyde levels in ALDH2*2 carriers were significantly higher than for the ALDH2*1/*1 genotype. Notably, the ratio of breath acetaldehyde level-to-breath ethanol level could identify carriers of the ALDH2*2 allele very accurately (whole accuracy; 96.4%). CONCLUSIONS: Our novel breath test is a useful tool for identifying ALDH2*2 carriers, who are at high risk for esophageal and head and neck cancers.

Endoscopic hemostasis for hemorrhage from an ileal diverticulum.

Hemorrhage from a non-Meckelian jejunoileal diverticulum is rare, and it is generally difficult to diagnose the source of the bleeding. Here, we report the case of a 59-year-old male with hemorrhage from an ileal diverticulum. Contrast computed tomography scans demonstrated the ileal diverticulum and extravasation of the contrast medium around it. The diagnosis was then made by computed tomography scans, and endoscopic mechanical hemostasis was performed under colonoscopy with three metal clips. The management of hemorrhage from jejunoileal diverticula is discussed.

Development of a compact and simple gas chromatography for oral malodor measurement.

BACKGROUND: Volatile sulfur compounds (VSCs) in oral air are the only type of gases correlated with the strength of oral malodor. We developed a compact and simple gas chromatograph (GC) equipped with a newly invented indium oxide semiconductor gas sensor (SCS) for measuring the concentrations of VSCs in mouth air. We have assessed the correlation between measurements with a GC-SCS and those with a regular GC. METHODS: Oral air samples from randomly selected volunteers were analyzed with both a GC-SCS and a GC with a flame photometric detector (FPD), which is specific to VSCs, and GC-SCS measurements were compared to those obtained by GC-FPD. Subsequently, oral air samples before and after mouthrinsing with 5% ethanol mouthwash were analyzed to determine the effect of ethanol on VSC measurements by GC-SCS. RESULTS: There were strong correlations between VSC concentrations determined using these two gas chromatography methods (hydrogen sulfide, R=0.821, P<0.0001; methyl mercaptan, R=0.870, P<0.0001; and dimethyl sulfide, R=0.770, P<0.0001). Although GC-SCS can differentiate ethanol and VSCs in oral air samples after mouthrinsing, GC-SCS measurements demonstrated higher values than those obtained by GC-FPD; however, this discrepancy improved over time due to the reduced effect of ethanol. CONCLUSION: The results suggest that GC-SCS may be useful for the diagnosis of halitosis.