In two small trials, the recent results of the two methods were similar based on local recurrence rates. Many European surgeons advocate TME, which is now standard practice. A trial from the Netherlands showed that TME had a lower local recurrence rate than conventional rectomies, but it also noted that obstruction of the blood supply to the rectal stump increased the incidence of postoperative anastomotic fistula. The reduced local recurrence rate two years after TME suggests that it is an effective means to reduce local recurrence even after extensive TME resection.
In two small trials, the recent results of the two methods were similar based on local recurrence rates. Many European surgeons advocate TME, which is now standard practice. A trial from the Netherlands showed that TME had a lower local recurrence rate than conventional rectomies, but it also noted that obstruction of the blood supply to the rectal stump increased the incidence of postoperative anastomotic fistula. The reduced local recurrence rate two years after TME suggests that it is an effective means to reduce local recurrence even after extensive TME resection.
Different uses of surgery alone and combination techniques have been studied with the aim of increasing local control rates. Most controlled studies of preoperative or postoperative radiotherapy alone have shown no improvement in survival. Local recurrence rates have also decreased to a small extent, and in the United States, treatment is usually given at a dose of nearly 5,000 cGy for more than 6 weeks, followed by surgery 4 to 6 weeks after completion. In Europe, radiotherapy alone is usually given with a dose of 25Gy divided into five exposures (5x5Gy) followed by immediate surgery, and no protocol has been validated for this type of protocol.
In patients with stage II and m colorectal cancer, recurrences were more common 2 years after radical treatment, and recurrences were less common thereafter. Five years after surgery, the main focus of follow-up was to detect new tumors. The main purpose of overseas medical treatment is the early detection of metastatic disease, some patients with colorectal cancer will appear single or multiple liver metastasis, lung metastasis (the so-called multiple metastasis state) and postoperative anastomotic recurrence, can be re-radical surgical resection. Chest CT scan has been widely used as a substitute for chest radiography in monitoring recurrence and metastasis, and patients are recommended to be reviewed annually or semiannually.
For patients with colonic obstruction on colonoscopy, if preoperative colonic imaging is performed, postoperative colonoscopy is recommended 3 to 6 months after surgery to ensure that there is no recurrent tumor in the remaining colon. The purpose of subsequent colonoscopy is to detect new tumors, recurrence of tumors at the suture, or colorectal adenomas. If there is no obstruction, annual colonoscopy 1 to 3 years after surgery is recommended, and if negative, follow-up every 5 years thereafter. Elevated CEA levels require further examination to identify the site of recurrence, and CEA levels are very effective in monitoring recurrence and metastasis in the liver. When CEA levels are elevated, further examination of the abdomen, pelvis, and chest CT is required, along with other tests based on the symptoms. If recurrence of rectal cancer in the pelvis is suspected, MRI is preferable to CT.
ASCO advocates regular intervals of CT, ultrasound, or MRI of the liver, and PET scans are valuable in identifying early signs of relapsed disease and in determining the number of relapses and metastases. Treatment of isolated recurrent foci in the liver or lung with early detection and surgical removal is usually curable or may improve survival. Patients with a single lesion and the disease-free interval from initial diagnosis to the onset of metastatic disease generally have a better prognosis at 3 years or more. The 5-year survival rate after surgical resection of isolated liver metastases with unilateral hepatic lobe involvement was 60%, the 5-year survival rate after surgical resection of isolated lung metastases was 40% and the 10-year survival rate was 20%.
The full cure rate decreases with the extent of metastasis, but patients with multiple metastases may still be cured by surgical resection. In some patients, even if the lung and liver have metastases, they can also be surgically removed with better results. With the advent of more effective chemotherapy drugs and biologics, it is becoming more common for previously inoperable patients to be operated on. For overseas medical patients who have the opportunity for surgical treatment, restaging should be performed from time to time, and resection should be performed if possible.