Volatile Organic Compounds and Esophageal Cancer: Understanding the Implications for Diagnosis and Treatment
While utilization of VOCs in the early detection of esophageal cancer has shown promise, future studies should aim at determining which VOCs would be the most specific in diagnosing GI malignancies.
Esophageal cancer consists primarily of squamous cell carcinoma (SCC) and adenocarcinoma (AC) cell types. SCC is the most common form of esophageal cancer in the world, however AC has become significantly more common in Western countries, including the United States, in the past several decades.1
SCC is more common in African Americans and is typically found in the middle third of the esophagus and associated with alcohol use and smoking. In contrast, AC is more common in Caucasians, is typically found in the distal esophagus, and is associated with a history of Barrett's Esophagus (BE).1
As with many malignancies, by the time the patient clinically presents with symptomatic esophageal cancer, the disease burden can be relatively extensive. Only approximately one-third of patients diagnosed with esophageal or gastric cancer are considered potentially curable.2
The most typical symptoms that patients present with are long standing gastroesophageal reflux (GERD), dysphagia, weight loss, and loss of appetite. To further complicated the diagnosis, not all patients with esophageal cancer will have the typical “alarm” symptoms such as dysphagia or weight loss that would prompt a visit to either their primary care physician or gastroenterologist. If esophageal cancer is suspected, imaging studies such as a barium swallow or computed tomography (CT) can often detect a suspicious lesion. Endoscopy with biopsy is the gold standard for obtaining tissue for histopathologic analysis.
It would be ideal to diagnose a patient with esophageal cancer very early on in their course with a relatively non-invasive, cost-effective, and accurate test. There is a lack of evidence to support screening in certain high risk populations with invasive and expensive tests such as endoscopy. One study found an estimated cost of close to $90,000 for detecting each upper gastrointestinal malignancy (including esophageal and gastric cancer) via endoscopy.3