Sunday, June 25, 2006

'Bloodless' Surgery Offers Hope for Cancer Patients

“Bloodless” operations, which remove affected tissue without invasive incisions, are making progress as hospitals compete with each other to introduce as it were cutting-edge surgical tools. From Gamma Knife to Haifu Knife, bloodless operations start with setting the three-dimensional coordinates of a lesion to be removed using advanced imaging equipment such as CT or MRI and are completed by concentrating thousands of beams of radiation from outside the body. Bloodless surgery is fast substituting traditional surgery with the scalpel as it is performed with negligible loss of blood and leaves barely a scar.

It started in the 1960s, when Gamma Knife radiosurgery was developed. The tool is considered the most accurate and safest among neurosurgical tools using radiation. “The Gamma Knife is far safer and more effective than operations that require incisions into the skull,” says Kim Dong-gyu, a professor of neurosurgery with Seoul National University Hospital. “What’s more, it’s more reliable than other recently introduced bloodless surgery tools because it’s been tried and tested for the past 40 years without problems.” But it has its drawbacks: it can be used only on the brain, and setting coordinates requires attaching a stereotactic frame to the patient’s head by drilling four holes into the skull.

The Cyber Knife, a successor to the Gamma Knife, is an advanced radiosurgical treatment, combining the latest robotic technologies with navigation technologies from NASA. As the focus of radiation beams moves along with patient’s movement, it works without the need for additional equipment to fix the patient’s body or anesthesia, unlike the Gamma Knife. The Cyber Knife can be used not only on the brain but also the pancreas, lung and other organs throughout the body and particularly on constantly moving organs such as stomach and colon. “Cyber Knife treatment is available for tumors as large as 5-6 cm and highly accurate as radiation beams are projected on the lesion from 1,248 different directions,” says Kim Moon-chan, the director of Gangnam St. Mary's Hospital’s Cyber Knife Center at Catholic University of Korea.

Tomotherapy is the latest radiation treatment equipment. It consists of a CT scanner that locates the targeted organs and a Linac or linear accelerator where radiation beams are projected. While the Gamma Knife and the Cyber Knife work on relatively small tumors, Tomotherapy can be used for any cancerous cells no matter how large they are. It has highly accurate by precisely controlling the intensity of radiation entering the patient’s body and is therefore very effective in treating multiple cancers, cancer of the esophagus, and lung cancer. The caveat is that it is not covered by insurance and patients pay more than W20 million (US $20,000) for the treatment.

The High Intensity Focused Ultrasound Therapeutic System or Haifu Knife projects ultrasound waves onto a lesion for 2-3 seconds so that the 65-90 degrees Celsius generated can burn out tumors. It is useful for breast cancer, osteosarcoma or bone cancer, pancreatic cancer and liver cancer. The pulsed Haifu, however, cannot penetrate air or solid tissue such as bones and cannot be used to treat colon or lung cancer. “The Haifu works on tumors regardless of their size as it doesn’t destroy healthy tissue, unlike other radiation treatment,” .(englishnews@chosun.com )

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