Esophageal cancer currently ranks sixth in the incidence of malignant tumors worldwide, but in China, it ranks fourth. Surveys show that the eastern Guangdong region and the Taihang Mountains in Hebei have become the two areas with the highest incidence and mortality rates in the country. The reason both regions "made the list" is due to dietary habits: residents of the Taihang Mountains love pickled vegetables, while the population of eastern Guangdong prefers preserved foods, and it is these foods that lead to cancerous changes.
It is reported that the incidence rate in the eastern Guangdong region is as high as 4 per 10,000 people. Because esophageal cancer has no specific symptoms, 90% of cases are already in the locally advanced stage when discovered. Experts remind that individuals with a history of esophageal cancer in their three generations of direct relatives, those aged 40 and over, and those experiencing swallowing discomfort should be screened immediately.
Medical Guidance/Professor Fu Jianhua, Vice President of the Sun Yat-sen University Cancer Center and Director of the Department of Thoracic Surgery: Closely related to the habit of eating pickled vegetables and preserved foods
"Esophageal cancer is closely related to geographical environment, dietary habits, and genetics. Surveys show that the areas with the highest incidence and mortality rates of esophageal cancer in our country are mainly concentrated in two places—the Taihang Mountains in Hebei and the eastern Guangdong region. Eastern Guangdong includes the Chaoshan and Hakka areas, with an incidence rate of about four esophageal cancer patients per 10,000 people," said Professor Fu Jianhua, Vice President of the Sun Yat-sen University Cancer Center and Director of the Department of Thoracic Surgery.
Why is esophageal cancer so common in these two regions? Experts explain that the habit of eating pickled vegetables in the Taihang Mountains has a long history. The local climate is cold and dry year-round, with inconvenient transportation, leading to a shortage of fresh vegetables. This caused people to rely on pickled vegetables for sustenance, and over time, homemade pickled vegetables became a local traditional food. However, from the esophageal cancer prevention and screening surveys in the Taihang Mountains, a close relationship was found between eating pickled vegetables and the high incidence of esophageal cancer, with the proportion of patients in this area ranking first in the country.
Not coincidentally, the southern eastern Guangdong region has a preference for preserved foods such as pickled vegetables, pickled cabbage, salted vegetables, fish, and shrimp paste. Corresponding to the Taihang Mountains, this area has also become the region with the highest incidence of esophageal cancer in the south. Fu Jianhua explains that long-term research suggests that the high incidence rates in these two areas are related to people's excessive consumption of pickled vegetables and preserved foods. Animal experiments have shown that feeding rats concentrated pickled vegetable water easily leads to esophageal and stomach cancer. It turns out that these foods contain a high proportion of nitrosamines, which can cause cancerous changes. Experts explain that preserved foods often have a high salt content and contain large amounts of nitrites to ensure a long shelf life, making them also likely to induce stomach cancer.
Experts remind the public to eat less preserved and non-fresh foods. Leftovers must be refrigerated promptly, as nitrites in such foods at room temperature will increase rapidly over time.
In addition, experts urge the public to eat less hot pot. Generally, the oral, esophageal, and gastric mucosa can only tolerate temperatures up to 50°C, while the temperature of hot pot broth can be as high as 120°C. Eating it immediately can easily scald the oral cavity, tongue, esophagus, and gastric mucosa. If the mucosa of the esophagus and other parts is frequently damaged, it can easily induce esophageal cancer.
Prevention: High-risk individuals must undergo regular annual screenings
Fu Jianhua told reporters that based on the situation of esophageal cancer patients admitted to the hospital, up to 90% are in the locally advanced stage. "It cannot be ruled out that the high proportion of severe patients in our hospital is due to the transfer of critical and late-stage cases, but overall, the detection rate for early and mid-stage esophageal cancer is too low," Fu Jianhua pointed out. Because esophageal cancer has no specific symptoms, swallowing difficulties only appear when the mucosa is damaged and the lesion has invaded two-thirds of the esophagus, leading to 90% of cases being locally advanced when discovered.
Since this disease mostly occurs after the age of 40, he recommends that people in the high-incidence eastern Guangdong region who are 40 years or older, have had esophageal cancer patients in their three generations of direct relatives, or experience swallowing discomfort should promptly undergo gastroscopy and esophagoscopy at the hospital to rule out cancer. "High-risk individuals must undergo regular annual screenings; esophageal cancer cannot be detected by routine physical examinations alone," Fu Jianhua emphasized. It is understood that the early "subtle signs" of esophageal cancer can manifest as the following four signals:
1. When eating dry food, it feels as if the food briefly stops at a certain point in the esophagus, sometimes as if there is food in the esophagus that cannot be swallowed. This sensation may heal on its own, but it often reappears after several days or weeks;
2. Often feeling as if something is stuck to the wall of the esophagus, unable to swallow it down;
3. Mild discomfort or pain behind the sternum when eating. The pain is brief, sometimes lasting only a few seconds. The pain worsens or lasts longer when eating coarse, hot, or irritating foods;
4. Frequently experiencing a premature feeling of fullness in the upper abdomen for no apparent reason when swallowing.
Treatment: It is best to use a comprehensive treatment method
Fu Jianhua explained that in the past, esophageal cancer was basically treated with surgical resection, but it was gradually discovered that more than half of esophageal cancer patients are not suitable for direct surgery alone. It turns out that when doctors remove the patient's esophagus, they also remove the patient's cardia, bilateral vagus nerves, and elevate the stomach's "position" from the abdominal cavity to the chest cavity to replace the removed esophagus. "Even if the surgery is perfect, this procedure will greatly compromise the quality of life," Fu Jianhua said. Removing the cardia means that after food enters, it is difficult to control, and food may easily flow from the mouth even when the body is horizontal; elevating the stomach affects the patient's digestion, absorption, and other functions to varying degrees, causing the patient to become malnourished and gradually lose weight.
Therefore, Fu Jianhua pointed out that if a patient is in the locally advanced stage or the overall mid-stage of the disease, they can first undergo preoperative radiotherapy and chemotherapy to kill tumor cells and shrink the esophageal tumor before surgery. He believes that for mid-stage esophageal cancer, a comprehensive treatment of radiotherapy, chemotherapy, and surgery is much more effective than surgery alone.