Surgery is usually indicated in cases of localized cancers. It may be done either alone or in combination with other lines of treatment such as radiation and chemotherapy.
If the cancer has not infiltrated into the surrounding areas and has not spread from the original site to different areas, then surgery may be all that is necessary. All the cancerous tissue has to be removed. In the process, even if a doubtful normal adjacent part is to be excised or surgically removed, this is done for the sake of safety and to prevent the recurrence of the cancer. The lymph glands enlarged or even suspicious, draining the area of cancer, are also resected or surgically removed.
Surgery is also resorted to in cases where the cancer is inoperable because of spread. This is done in order to remove any obstruction in a vital part of the body such as the intestines or bronchi of the lungs.
Surgery is also undertaken sometimes so that the patient is saved from very severe pain.