Pinpointing cancer cells
Its name sounds like a science-fiction movie, but it’s real. One of the latest weapons in the battle against cancer, the CyberKnife combines sci-fi–like radiation technology with computer-guided imagery to destroy tumors without surgery.
Its name sounds like a science-fiction movie, but it’s real. One of the latest weapons in the battle against cancer, the CyberKnife combines sci-fi–like radiation technology with computer-guided imagery to destroy tumors without surgery.
The machine delivers radiation produced by a small linear accelerator. That in itself isn’t new; this process, known as radiosurgery, has been around for decades. What makes it special is a robotic arm that allows the energy to be directed at any part of the body from any direction. This means it can treat tumors almost anywhere— even hard-to-reach areas deep within the body— using high-dose radiation delivered with pinpoint precision, minimizing damage to surrounding healthy tissue.
Only about 100 U.S. hospitals have this technology, and Saint Peter’s University Hospital will join them in early 2010, when CyberKnife will be installed to treat patients in its Department of Radiation Oncology. The CyberKnife sends more than 100 beams of energy, each from a different angle, says Scarlett Szymanski, director of Ambulatory Oncology Services. “Each beam by itself is not dangerous, but when they converge on the tumor, their energy combines for higher doses than with usual radiation. That’s when they kill the tumor.”
The process is especially helpful in reaching organs that are tough to treat conventionally, such as the lung, brain, prostate and pancreas. “There are critical structures near these organs, and high doses of conventionally delivered radiation might damage those structures,” says Gopal Desai, M.D., chairman of Radiation Oncology. “Because CyberKnife is more precise, it’s like performing surgery without cutting into the patient.” Each session takes up to 90 minutes, but because the dosages are so high and so accurate, fewer sessions are needed. “A prostate tumor may need just four treatments, not the 44 treatments typically needed with conventional radiation,” Dr. Desai says.
CyberKnife also employs continual image guidance technology and computer-controlled robotic mobility to correct for tumor and patient movement in real time. “It doesn’t require devices to keep the body or head stable as other radiation delivery systems do,” says Dr. Desai. “The precision guidance allows the patient to breathe normally and adjusts for small movements during treatment,” says the doctor. “It’s similar to the guidance technology that is used with cruise missiles.”
The CyberKnife is approved to treat tumors in the brain, head, prostate, pancreas, neck, liver, lung, vascular system and spine. “Saint Peter’s has always been at the forefront in cancer technology; this is one more step in improving cancer-care quality,” says James Gervasoni Jr., M.D., chairman of Surgery. “As New Brunswick’s only CyberKnife, it’s an advance for our whole community.”
