Medicine: Advancing Radiotherapy

His body gowned in cotton and his soul cloaked in despair, the cancer patient held few hopes two decades ago when he was wheeled to the hospital radiotherapy room. X ray usually was tried when surgery was impossible. Successful treatments were few, and often bought at the cost of radiation burn, nausea, anemia, and pneumonitis.

Last week, at the American Roentgen Ray Society meeting in Miami Beach, it was apparent that radiotherapy is rapidly fighting its way out of the last-resort category. Said Memorial Sloan-Kettering’s

Dr. James Nickson: “Over the next decade, radiotherapists will see not minor, slow changes in their ability to help patients. There should be quantum jumps in their ability to do so.”

With Oxygen. Drs. Harold Atkins and William Seaman of New York’s Colum bia-Presbyterian Medical Center told of progress toward licking a basic problem—radiosensitivity. Since Wilhelm Roentgen discovered X rays, in 1895, radiotherapists have been trying to get radiation to destroy diseased tissue while letting healthy nearby tissue survive.

First at London’s St. Thomas’s Hospital, and lately at Columbia-Presbyterian, plain oxygen has proved to be a useful ally toward this goal. Cells are more easily destroyed if they have a large supply of oxygen, but tumor cells are frequently oxygen-starved; they grow so rapidly that they outstrip their blood supply. Radiotherapists speculated that they might make up the deficiency by putting the patient in a chamber where he could breathe oxygen at a pressure four times that of the atmosphere. A high concentration of oxygen could then be carried in the bloodstream to the tumor cells.

In practice, Drs. Atkins and Seaman and others on the Columbia-Presbyterian team, pick patients with advanced cancer to treat with oxygen and radiation. According to a carefully devised procedure, such a patient gets an anesthetic injected into his veins, and a rubber hose is threaded down his windpipe so that he will not choke while asleep. His eardrums are pricked so that oxygen pressure will not perforate them. Monitoring devices, including a microphone that allows the anesthesiologist to listen to respiration, are attached to the body. The patient is put on a stretcher that is placed in the oxygen chamber.

As a team of six doctors, nurses, and technicians hover at chamber-side, the radiologist maneuvers a betatron into position. After slamming shut a hatch at the end of the chamber, technicians force oxygen in. After 15 minutes under full pressure, during which the patient’s body is closely watched by means of closed-circuit television, the radiologist turns on the betatron, shoots radiation at the tumor. Following treatment, the patient is decompressed in deep-sea-diver fashion and taken to the recovery room.

The results so far have done more to confirm the theory than to cure patients, for it has been tried only on poor risks. But, says Dr. Atkins, “even though we need to try it on other kinds of patients, we think that we are on to something, and we are going to pursue the idea further.”

With Drugs. Other researchers hope to enhance the effects of radiation by means of drugs, and they have a promising entry. In cases of Wilm’s tumor—a form of kidney cancer—actinomycin D is given intravenously to the patient. Its action reaches cancer cells that have already spread to surrounding tissue. Radiation reduces the size of the tumor, and surgery removes it. The technique is not without its hazards; actinomycin D increases skin reactions to radiation. But a group of University of Illinois researchers reported at Miami Beach that the undesirable side effects could largely be avoided if the “irradiated skin field temperature” is lowered by cold water to less than 55°.

While they are pecking away at the frontiers of radiotherapy with oxygen and drugs, radiotherapists are improving conventional X-ray treatment, using new isotopes, and employing many new variations on old techniques:

> Beamed from a supervoltage machine, cobalt-60 has largely replaced conventional X ray in treating cancers of the head, esophagus, neck, cervix, uterus and bladder; higher dosages of cobalt-60 can be given with far less reaction to the patient’s skin compared with low-voltage X-ray machines.

> A 2 5-million-volt betatron is used at Ohio State University Medical Center to throw out nuclear particles of such high penetrating power that cancers hidden behind thick layers of bone can be treated with relatively little damage to healthy tissue.

> Phosphorus-32 migrates to the bone marrow, aids in the destruction of blood cancers.

> Iodine-125 finds its way to the thyroid, maiming cancers there.

> Gold-198 tends to stop malignant cancer from spreading in the chest and abdominal cavities.

Many of the newer radiotherapy techniques require expensive equipment and well-trained therapists. The problem now facing U.S. medicine is to bring both to the grass-roots general hospital. Recognizing the need, the U.S. Public Health Service last week prepared to give training stipends to radiotherapists, increased financial aid to medical schools and teaching hospitals.