Oncosurgery

Symptoms of colon and rectal tumours

Malignant tumours of the colon can remain asymptomatic for a long time, which is why screening for colorectal cancer is of particular importance. The most common symptoms are bloody, baggy stools, diarrhoea, changes in bowel movements, abdominal cramps, bloating and weight loss. Generally, as the tumour grows, symptoms become more pronounced.

Screening and diagnosis

The most common method is a faecal blood test, for which a stool sample is all that is needed. The technique is simple, cheap and convenient, but its sensitivity is not 100%. The most reliable method of screening for colorectal cancer is colonoscopy, which can be performed under general anaesthesia without any discomfort. As the test can remove polyps, it can also prevent the development of colon cancer. If a suspicious tumour is found, a histological sample can be obtained during the colonoscopy. If the sample confirms the presence of malignant cells, further tests are required, commonly known as ‘staging’. This involves ultrasound, CT, MRI and less commonly PET-CT scans to look for the presence of tumour metastases in the lymph nodes or other organs, particularly the liver and lungs. Knowing the stage of the tumour is essential to plan the appropriate treatment.

Treatment of colorectal tumours

The treatment of colorectal cancer always requires a complex team approach. This team consists of an oncology specialist, an oncologist, a radiotherapy specialist, a radiologist, a pathologist, a stoma specialist and an onco-psychologist. The stage at which the tumour is detected determines the extent and order in which the oncologist, the radiotherapist and the oncology specialist are involved in the patient’s care. In all cases, the treatment plan is decided or approved by a team of specialists, called an ‘onco-team’.

Surgery

Surgery plays a central role in the complex therapy of colorectal cancer. Modern oncological surgery involves the removal of the tumorous colon section with an appropriate safety zone, as well as the chain of lymph nodes and lymphatic vessels supplying the affected colon section. The continuity of the bowel is restored with sutures or special suturing machines.
Depending on the part of the colon where the tumour is located, a right or left colon resection (right or left hemicolectomy), a segmental resection of the colon, a sigmoid colon or a rectal resection may be performed. Depending on the location of the rectal tumours, temporary or, in rare cases, permanent bowel evacuation (stoma) may be required during surgery.

The majority of operations can be performed without an abdominal incision using laparoscopic surgery, a technique that reduces post-operative pain and helps speed recovery. Based on histological examination of the tumour and associated lymph nodes removed during surgery, the ‘onco-team’ will recommend any chemotherapy that may be needed.
The treatment of tumours of the rectum is somewhat different from that of other parts of the colon. For early stage rectal tumours, local excision through the rectum (TAE) or total wall excision with a special surgical microscope (TEO, TAMIS) may be performed in some cases. For more advanced rectal tumours, these techniques are not sufficient and partial or total removal of the rectum may be necessary. In these cases, surgery is often preceded by radiotherapy, which reduces the rate of tumour recurrence and increases the chances of sphincter-preserving surgery. Also in the case of rectal tumours, the results of histological examination determine the need for chemotherapy.
If metastases develop in the liver, surgical removal should also be sought. This can be done before, at the same time as or after intestinal surgery. In the majority of cases, surgical treatment is combined with chemotherapy for a better outcome. Some liver metastases can also be removed by laparoscopic technique.