A 57-year-old man presents with abdominal pain and vomiting. Which structure is most likely perforated in cases of peptic ulcer disease?

In cases of peptic ulcer disease, the structure that is most likely to become perforated is the duodenum. Peptic ulcers can occur in both the stomach and the duodenum, but duodenal ulcers are significantly more common and are more likely to lead to perforation. When a duodenal ulcer erodes through the wall of the duodenum, it can create a direct connection to the peritoneal cavity, leading to peritonitis, which is a serious and potentially life-threatening condition.

The duodenum is particularly susceptible to ulcers due to its exposure to gastric acid and pepsin as it receives chyme from the stomach. This environment, coupled with factors such as Helicobacter pylori infection and the use of nonsteroidal anti-inflammatory drugs (NSAIDs), contributes to the development and potential perforation of duodenal ulcers.

In contrast, while both the stomach and other structures like the esophagus can also ulcerate, the incidence of perforation is much lower in these areas compared to the duodenum. The transverse colon, being part of the large intestine, is generally not associated with peptic ulcer disease and is not a typical site for ulcerative processes related to peptic ulcers. Therefore,