Colorectal cancer follow-up… is there any chance of a consensus?

Colorectal cancer is the third most common cancer in the world, with approximately 1.4 million new cases and 694,000 deaths every year. The most complex form of the disease occurs when cancer affects the rectum, which accounts for one third of all colorectal cancers. Nowadays, at 5 years, the risk of locoregional recurrence in rectal cancer is below 10% and the disease-free survival rate is over 70%. It is therefore necessary to develop specific follow-up programs to detect recurrences as soon as possible, increasing the possibilities of resection, and therefore improving survival rate.

Four Societies focus on cancer prevention, diagnosis, treatment, and surveillance: the European Society of Medical Oncology, or ESMO; the National Comprehensive Cancer Network, which represents an alliance of almost 30 US centers designated by the US National Cancer Institute; the American Cancer Society; and the American Society of Clinical Oncology. Physicians all around the world follow their recommendations, which are obviously based on the available evidence. 

The basics that physicians should know are the following:

- A high level of evidence confirms that intensive follow-up must be carried out in both colon and rectal cancer patients.

- A history and physical examination establishing CEA levels are advised every 3-6 months for 3 years and every 6-12 months at 4 and 5 years after surgery.

- A colonoscopymust be carried out at year 1 and every 3 to 5 years thereafter, looking for metachronous adenomas and cancers.

- A CT scan of the chest and abdomen every 6-12 months for the first 3 years can be considered in patients who are at a higher risk of recurrence - i.e. stage 2 and 3 colon cancer, and stage 1 patients with high-risk features. In rectal cancer, the recommendations are the same, but including the pelvis in the radiological study. 

- A contrast-enhanced ultrasound could replace the abdominal CT scan in colon cancer.

However, not all societies have reached a consensus in every area. This will be addressed in this talk, revieweing general recommendations to optimize patient outcomes, as well as examining the best surveillance practices in special cases such as hereditary syndromes and stage IV colorectal cancer patients.