End-stage symptoms
If the disease is already more advanced, the infestation can be so severe that the intestinal lumen is completely displaced and an intestinal obstruction (ileus) occurs. This can lead to vomiting with faecal obstruction in later stages. This can also lead to severe and seizure-like cramps and pain.
In the advanced stages and especially in the final stage of the disease, pain is generally more frequent. Depending on the location of the intestinal cancer, this pain occurs in the abdominal area (cancer in the colon) or in the area of the lumbar spine (cancer in the rectum). The latter pain thus dominates as back pain and is often not initially associated with bowel cancer.
If the cancer has already spread to other organs (metastases), further symptoms may occur depending on the organ and extent. It is important to note that during the early stages of the disease, there are usually no clear symptoms, but especially in the final stages there are more symptoms and complaints. Unfortunately, this is then often too late and the colon cancer is too advanced. It is precisely because of these often missing early warning signals that it is important to be aware of them in time for early detection examinations and, above all, to have early and uncharacteristic signs clarified in good time.
Summary
Colorectal cancer often remains completely without symptoms for a long time and develops few characteristic signs of the disease as it progresses. The most characteristic symptom is blood in the stool, which is caused by ulceration of the tumour surface. The blood can be deposited on the stool or mixed with the stool, but in most cases it occurs in the form of so-called hidden (occult) blood.
This hidden blood can be diagnosed during the screening with a special test (haemoccult test). During the course of the disease, changes in bowel movements can occur. Diarrhoea and constipation often alternate.
Less frequently, the severe tumour constriction of the intestine leads to changes in the shape of stools such as “pencil stools” and “goat’s faeces”. If the tumour shows a constant loss of blood, anaemia can occur in the long term, which is manifested by fatigue and loss of performance. As with almost every tumour disease, in the later stages, an immense weight loss (tumour cachexia), increased temperature (tumour fever) and pain in the area of the tumour can occur.
If tumor metastases have already settled in the liver (liver metastases), swelling and loss of liver function can occur, which is reflected in a yellowing of the skin (icterus). If the tumour settles in the skeletal system (skeletal metastases), bone pain develops, which is accompanied by a particularly strong, destructive pain character. Metastases in the lung sometimes cause shortness of breath (dyspnoea), coughing up blood (haematemesis) and pneumonia.