If a colectomy is recommended for a benign, or non-cancerous growth, it is usually because that growth is symptomatic in some way (bleeding or causing a blockage) or to prevent it from progressing into a cancer. In the case of diverticulitis or inflammatory bowel disease, colectomy is used to remove a segment that is affected by severe inflammation or infection.
When a colectomy is needed to treat a malignant (cancerous) tumor, the surgeon must remove both the tumor and the vascular and lymph structures supplying that portion of the colon. This operation can be curative, depending on the stage of the cancer. Patients who have a colectomy for cancer will meet with a medical oncologist soon after they have recovered from surgery to determine if further treatment such as chemotherapy is required.
The potential complications after colectomy include bleeding and infection, injury to nearby structures including the intestines, the bladder, blood vessels and the ureter (a tube that carries urine from the kidney to the bladder). It is always possible that a leak can occur where the intestines were reconnected (the anastomosis). Blood clots can occur in the veins, and these can travel to the lungs. Hernia at the surgical incisions or bowel obstruction from internal scar tissue can also occur, even years later.