A Complete Guide to Surgical Treatment of Colon Cancer

A Complete Guide to Surgical Treatment of Colon Cancer

Preface
Surgery is the most common treatment for colon cancer, especially for early-stage cases. The type of colon cancer surgery depends on the cancer stage (whether distant metastasis has occurred), pathological type, location, size, and surgical purpose. Colon cancer surgery differs from rectal cancer surgery.

For very early-stage cancer, surgeons can remove the lesion directly via colonoscopy, often practicing and refining their technique using a Colonoscopy Simulator​ beforehand. In most cases, however, partial colon resection together with adjacent lymph nodes is required. As part of the lymphatic system, lymph nodes are usually the first site of cancer spread. If colon cancer has metastasized to the liver or lungs, systemic therapy such as chemotherapy is generally adopted. Only a small number of patients may require surgical resection of the tumor, for instance when intestinal obstruction is caused by the cancer.

Such operations are performed by specialized colorectal surgeons or general surgeons, either via open surgery or laparoscopic surgery. A stoma may be required after surgery - an opening created on the abdominal wall through which stool drains into a disposable ostomy bag attached to the abdomen. For most colon cancer patients, the stoma is temporary, while a small number require a permanent stoma.
Polypectomy and Local Resection
Certain early-stage colon cancers (Stage 0 and some early Stage I tumors) and most colonic polyps can be removed during colonoscopy. A colonoscope is a long, flexible tube fitted with a tiny camera at the tip, which is inserted through the rectum into the colon. These procedures are performed during colonoscopy without the need for abdominal incisions.

In polypectomy, cancerous tissue is removed as part of the polyp, which is excised at its stalk (the mushroom-like base). The procedure is typically completed using an electrified wire loop on the colonoscope to cut off the polyp from the colonic wall.

Local resection is a slightly more complex procedure. Surgeons use specialized instruments through the colonoscope to excise small tumors on the colonic lining along with a small margin of normal colonic tissue to ensure negative resection margins. The resected specimen is examined by a pathologist. If high-grade pathological features are found, a second surgical procedure may be recommended to remove more colonic tissue, ensuring no cancer cells remain at the resection margin.

Colectomy
Surgeries are named differently according to the tumor location: Surgeons resect the cancerous colonic segment along with a small section of normal colon on both sides. Depending on tumor size and location, approximately one-quarter to one-third of the colon is removed in most cases, followed by reconnection of the remaining colonic segments. Before performing the actual operation, many surgeons practice on a Colonoscopy Simulator​ to ensure precision and safety. Based on the tumor's position, the procedure is named accordingly as hemicolectomy, partial colectomy or segmental resection.

Total colectomy refers to the removal of the entire colon, which is rarely used for routine colon cancer treatment. It is only indicated when other lesions exist in cancer-free colonic segments, such as hundreds of intestinal polyps in patients with familial adenomatous polyposis, or certain cases of inflammatory bowel disease.

After tumor resection, the two ends of the remaining bowel are reconnected. Occasionally, to allow the intestinal tract time to heal without stool passing through the surgical incision, surgeons create an opening from the intestinal end onto the abdominal wall as a stoma for fecal drainage.

Laparoscopic-Assisted Colectomy
The operation is performed through 4 to 5 small abdominal incisions with specialized surgical instruments. A laparoscope is a long, thin illuminated tube equipped with a miniature camera and light source, enabling surgeons to visualize the abdominal cavity internally. The laparoscope is inserted through one small incision, while surgical instruments are placed through the others for tumor resection.

Characteristics of Laparoscopic Surgery
Suitable for colon cancer patients with small tumors and early clinical stages.

In large colorectal surgery centers with high annual volumes of colorectal cancer cases, laparoscopic surgical techniques are highly mature (subject to the experience of the attending surgeon), though proficiency may be limited in primary-level hospitals.

Generally moderate in overall medical costs.

For patients with similar conditions, laparoscopic surgery takes longer than open surgery but less time than robotic surgery, requiring relatively better physical health and overall stamina from patients.

Small surgical incisions and shorter postoperative recovery time compared with open surgery.

There is a certain risk of intraoperative conversion to open surgery (due to inability to achieve complete tumor resection), meaning the patient may require a second operation.

Current clinical studies show comparable long-term survival outcomes between laparoscopic and open surgery for colon cancer patients.