At present, the early diagnosis rate of gastric cancer in China is only 10% to 20%, and most patients have already developed to the middle and late stages when gastric cancer is detected, with an overall 5-year survival rate of only about 35%. Although gastroscopy and pathological biopsy are the gold standard for diagnosing gastric cancer, few people are willing to undergo gastroscopy voluntarily because it is an invasive test and the patient often experiences significant nausea and discomfort during the test. The newest addition to the list is the newest addition to the list.
The breath test for H. pylori (Hp) is familiar to many people. So, is there a similar method that can detect gastric cancer simply by “breathing in”?
Why can breath testing technology diagnose gastric cancer?
How can breath testing technology diagnose stomach cancer?
Breath testing technology, as the name implies, is a diagnostic technique that detects the composition, concentration, and chemical reactions of various gases in the breath. The C/C breath test for detecting Helicobacter Pylori (Hp) in the human GI tract is one such test. However, this test can only detect the presence of H. pylori, suggesting a possible high risk of gastric cancer, and is not relevant for the diagnosis of gastric cancer.
Some researchers have found that gas exhaled by patients with gastric cancer contains a range of volatile organic compounds (VOCs), which in layman’s terms means that it contains specific gas components that are different from those exhaled by normal people. Checking for these differences through breath testing can detect gastric cancer. This is the theoretical basis for the use of breath testing technology for gastric cancer diagnosis.
How is breath testing done?
Before the breath test, the person should fast and abstain from water for at least 4 hours and avoid strenuous exercise before exhalation if possible. Rest quietly 1 hour prior to the test. During the test, the subject takes a deep breath and then exhales into the test device, where the gas passes through a special syringe and reaches a special gas storage container. The breath test is usually completed within a few minutes. Because the test is actually a deep breath, there are not as many precautions as other tests such as gastroscopy, and the results are usually available within a few hours.
How accurate is it to diagnose stomach cancer?
Scientists in the United Kingdom found that the levels of five compounds in exhaled breath were significantly associated with the development of gastric cancer, and that breath tests for these five components were 85% accurate in diagnosing gastroesophageal cancer (44% of patients with gastric cancer and 22% of gastroesophageal cancer in the population examined), specifically, breath tests had a sensitivity of 80% and a specificity of 81%, meaning that In addition to the fact that 8 out of 10 patients can be diagnosed by breath testing, less than 2 out of 10 normal people are misdiagnosed with gastroesophageal cancer.
A study of 130 test subjects (37 with gastric cancer, 32 with gastric ulcers, and 61 with other types of gastric disease) showed that in addition to being accurate in about 90% of gastric cancers, breathalyzer technology was able to compare the stage of gastric cancer, i.e., early or late gastric cancer, with 94% accuracy.
The breathalyzer technique is still a step down from the 99.99% diagnostic rate of gastroscopic biopsy, but it has some value as a noninvasive test in the diagnosis of gastric cancer, especially in the screening of early gastric cancer.
What are the characteristics of breath testing technology?
The advantages of breath testing technology.
The advantages of breath testing technology are undeniable: the test is non-invasive, there is no discomfort such as nausea during the test, it is convenient and quick, and it is accurate to a certain degree.
However, respiratory testing has its shortcomings: it is still in its infancy, the sample size is still insufficient, and studies in larger populations are needed to confirm the reliability of the technology; it can only be used as an adjunctive diagnostic tool, and the final diagnosis still requires tissue biopsy for pathological analysis. Therefore, the breath test technique is more for screening than for confirming the diagnosis of gastric cancer.
In summary, breath testing is one of the emerging tools for the diagnosis of gastric cancer and has the advantages of being noninvasive, rapid, and convenient. Further exploration of breath testing technology is imperative and will be a great help in promoting early detection, early diagnosis, and early treatment of gastric cancer. (Coauthored by Siwei Pan, Department of Gastrointestinal Oncology, The First Hospital of China Medical University)