Causes of constipation in late stage lung cancer

Lung cancer patients have recently reported a problem that they are prone to constipation. What is going on? Today, in order to solve this problem for many people, the editor has collected relevant knowledge and will tell you several reasons for constipation in the late stage of lung cancer.

1. The impact of the tumor itself

Primary or metastatic tumors in the abdomen and pelvis can cause intestinal obstruction, which hinders the passage of intestinal contents, resulting in very little stool reaching the rectum, which cannot trigger the defecation reflex and cause constipation; or constipation can be caused by extraintestinal tumors compressing the intestine. In addition, when the tumor invades the lumbar spine and causes spinal cord injury or when the tumor invades the nerves and causes nerve damage, it can also cause the defecation motor muscles to be damaged to varying degrees, resulting in weakened defecation power; at the same time, the conduction nerves are damaged, and the urge to defecate cannot be transmitted to the brain to produce a defecation reflex, which causes stool retention and constipation.

2. Indirect effects of tumor factors

After chemotherapy begins, patients eat high-fat, high-protein, low-fiber foods to increase nutrition, which causes feces to move slowly in the intestines, and the stools become dry and hardened into lumps; or because they eat too little or their diet is too refined, the fiber content is insufficient, and the stimulation to colon movement is reduced; in addition, bowel habits are disturbed due to factors such as changes in lifestyle, surrounding environment, and mental stress; thirdly, long-term bed rest and reduced activity lead to slower intestinal peristalsis; chronic consumption, malnutrition, or aging and weakness leading to muscle atrophy or decreased strength are also important causes of constipation.

3. Iatrogenic constipation

Opioid analgesics are one of the important reasons. Clinically, this type of constipation is called opioid-induced bowel dysfunction (OBD). There are a large number of opioid peptides in the gastrointestinal tract. When opioid receptors act on the central nervous system, the intestinal emptying time is delayed and the anal sphincter spasms, causing delayed stool transmission. The receptors acting on the gastrointestinal tract can also reduce the secretion of gastrointestinal glands and harden the stool. At the same time, because the stool stays in the colon for too long, excessive water absorption can also cause hardened stool.