Introduction
Pain is rather an untypical symptom of colorectal cancer. The danger of this tumour disease is that the cancer can grow and spread unnoticed in the intestinal wall for a long time before the first symptoms appear. There are therefore no early symptoms. In addition to frequent constipation, blood in the stool, rapid weight loss and an inexplicable drop in performance, pain in the abdomen and back as well as pain during bowel movements or digestion can be unspecific symptoms of intestinal cancer. Persistent or frequently recurring pain should be diagnosed by a doctor, even if it is rarely associated with intestinal cancer.
Why does bowel cancer cause pain?
Tumours in the intestine can grow without symptoms for a long time. If a bowel cancer causes pain, this can happen for various reasons. In almost all cases, the cancer is already well advanced with a locally large tumour and possible metastases in other areas and organs of the body.
First of all, the cancer can grow into the interior of the intestine, so that the digestion and excretion of stool is hindered there. Depending on the location of the cancer, pain may occur relatively early on during bowel movement. This is especially the case if the tumour is located near the rectum, the so-called “rectum”.
Even in higher sections of the intestine, blocking the digested food can sometimes cause severe pain. If a complete blockage occurs in the large intestine, this is called a “mechanical ileus”. This is a life-threatening symptomatology that can be accompanied by enormous cramps and pain in the abdomen.
Large intestinal cancers can also cause pain outside the intestinal lumen. This is the case when it presses on surrounding organs and structures and displaces them. This can affect the spleen, liver, abdominal wall and other structures in the abdomen.
More rarely, the pain is due to the potentially already existing metastases of the intestinal cancer. These can form in the liver, lungs or bones, for example. There they can change the organ and cause pain. When intestinal cancer is discovered, in many cases there are already metastases in the liver, whose capsule is very sensitive to pain and can be affected by the cancer.
Where is the pain located?
The location of the pain may vary. A distinction must be made between pain caused by the tumour locally at its original organ and pain caused by potential metastases. Many tumours are located in the central parts of the colon.
These lie superficially under the abdominal wall, which means that the pain is also projected onto the abdomen. They can occur in the lower abdomen, the side or the upper abdomen. Colon cancer that affects the rectum, on the other hand, can sometimes project its pain onto the lumbar spine or anus.
More frequent, however, are pains caused by metastases of the intestinal cancer. Especially metastases in the liver are not uncommon in colorectal cancer. They can lead to swelling of the liver, tension in the liver capsule, blockage of the blood vessels and consequently to jaundice.
A typical side effect is pain in the right upper abdomen. Lung metastases can also be formed by the intestinal cancer. They only cause pain if they grow into the peripheral areas of the lung that are sensitive to pain.
In rare cases, metastases also form in the bones. In principle, this can affect all bones and sometimes lead to severe pain. They can be located anywhere in the body and cause bone pain from the feet to the skull.
Back pain is a very unspecific symptom of colon cancer. Only in rare cases can it be attributed to the cancer disease itself, often harmless tension or spinal complaints are behind it. In rare cases, however, bowel cancer can be directly or indirectly responsible for the pain.
Especially tumours in the last section of the intestine, the so-called “rectum“, can cause pain in the coccyx and lower spine. This may also be related to the fact that the tumour grows strongly in the direction of the spinal column and presses on nerve plexuses there or infiltrates them. Indirectly, bone metastases as a long-term consequence of colon cancer can also cause back pain.
These can destroy the bone and the individual vertebral bodies and cause considerable pain. Instabilities of the spinal column can also result, which can be accompanied by secondary injuries. Abdominal pain can occur at an advanced stage of bowel cancer.
Bowel cancer usually develops slowly from small precursors in the bowel wall and does not cause any symptoms for a very long time. In most cases, abdominal pain also occurs only after a long period of time, when the tumour already causes blockages inside the intestine and discomfort to the neighbouring organs and structures in the abdominal cavity. Blockages in the intestine can initially still lead to occasional constipation and painful bowel movements.
Later, however, in an emergency, they can cause a mechanical ileus, i.e. an intestinal obstruction. The pain of this disease is enormous and sometimes the intestinal obstruction can be an acutely life-threatening symptom. Over time, the tumour grows from the inner mucosa of the intestine through the wall layers of the intestine and can subsequently press and infiltrate the peritoneum, the abdominal wall or surrounding organs in the abdominal cavity.
This can lead to considerable abdominal pain. Over time, the tumour grows from the inner mucosa of the intestine through the wall layers of the intestine and can subsequently penetrate and infiltrate the peritoneum, the abdominal wall or surrounding organs in the abdomen. This can lead to considerable abdominal pain.