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24 August 2009

Mammography

The invention: The first X-ray procedure for detecting and diagnosing breast cancer. The people behind the invention: Albert Salomon, the first researcher to use X-ray technology instead of surgery to identify breast cancer Jacob Gershon-Cohen (1899-1971), a breast cancer researcher Studying Breast Cancer Medical researchers have been studying breast cancer for more than a century. At the end of the nineteenth century, however, no one knew how to detect breast cancer until it was quite advanced. Often, by the time it was detected, it was too late for surgery; many patients who did have surgery died. So after X-ray technology first appeared in 1896, cancer researchers were eager to experiment with it. The first scientist to use X-ray techniques in breast cancer experiments was Albert Salomon, a German surgeon. Trying to develop a biopsy technique that could tell which tumors were cancerous and thereby avoid unnecessary surgery, he X-rayed more than three thousand breasts that had been removed from patients during breast cancer surgery. In 1913, he published the results of his experiments, showing that X rays could detect breast cancer. Different types of Xray images, he said, showed different types of cancer. Though Salomon is recognized as the inventor of breast radiology, he never actually used his technique to diagnose breast cancer. In fact, breast cancer radiology, which came to be known as “mammography,” was not taken up quickly by other medical researchers. Those who did try to reproduce his research often found that their results were not conclusive. During the 1920’s, however, more research was conducted in Leipzig, Germany, and in South America. Eventually, the Leipzig researchers, led by Erwin Payr, began to use mammography to diagnose cancer. In the 1930’s, a Leipzig researcher named W. Vogel published a paper that accurately described differences between cancerous and noncancerous tumors as they appeared on X-ray photographs. Researchers in the United States paid little attention to mammography until 1926. That year, a physician in Rochester, New York, was using a fluoroscope to examine heart muscle in a patient and discovered that the fluoroscope could be used to make images of breast tissue as well. The physician, Stafford L. Warren, then developed a stereoscopic technique that he used in examinations before surgery. Warren published his findings in 1930; his article also described changes in breast tissue that occurred because of pregnancy, lactation (milk production), menstruation, and breast disease. Yet Stafford’s technique was complicated and required equipment that most physicians of the time did not have. Eventually, he lost interest in mammography and went on to other research. Using the Technique In the late 1930’s, Jacob Gershon-Cohen became the first clinician to advocate regular mammography for all women to detect breast cancer before it became a major problem. Mammography was not very expensive, he pointed out, and it was already quite accurate. A milestone in breast cancer research came in 1956, when Gershon- Cohen and others began a five-year study of more than 1,300 women to test the accuracy of mammography for detecting breast cancer. Each woman studied was screened once every six months. Of the 1,055 women who finished the study, 92 were diagnosed with benign tumors and 23 with malignant tumors. Remarkably, out of all these, only one diagnosis turned out to be wrong. During the same period, Robert Egan of Houston began tracking breast cancer X rays. Over a span of three years, one thousand X-ray photographs were used to make diagnoses. When these diagnoses were compared to the results of surgical biopsies, it was confirmed that mammography had produced 238 correct diagnoses of cancer, out of 240 cases. Egan therefore joined the crusade for regular breast cancer screening. Once mammography was finally accepted by doctors in the late 1950’s and early 1960’s, researchers realized that they needed a way to teach mammography quickly and effectively to those who would use it. A study was done, and it showed that any radiologist could conduct the procedure with only five days of training.In the early 1970’s, the American Cancer Society and the National Cancer Institute joined forces on a nationwide breast cancer screening program called the “Breast Cancer Detection Demonstration Project.” Its goal in 1971 was to screen more than 250,000 women over the age of thirty-five. Since the 1960’s, however, some people had argued that mammography was dangerous because it used radiation on patients. In 1976, Ralph Nader, a consumer advocate, stated that women who were to undergo mammography should be given consent forms that would list the dangers of radiation. In the years that followed, mammography was refined to reduced the amount of radiation needed to detect cancer. It became a standard tool for diagnosis, and doctors recommended that women have a mammogram every two or three years after the age of forty. Impact Radiology is not a science that concerns only breast cancer screening. While it does provide the technical facilities necessary to practice mammography, the photographic images obtained must be interpreted by general practitioners, as well as by specialists. Once Gershon-Cohen had demonstrated the viability of the technique, a means of training was devised that made it fairly easy for clinicians to learn how to practice mammography successfully. Once all these factors—accuracy, safety, simplicity—were in place, mammography became an important factor in the fight against breast cancer. The progress made in mammography during the twentieth century was a major improvement in the effort to keep more women from dying of breast cancer. The disease has always been one of the primary contributors to the number of female cancer deaths that occur annually in the United States and around the world. This high figure stems from the fact that women had no way of detecting the disease until tumors were in an advanced state. Once Salomon’s procedure was utilized, physicians had a means by which they could look inside breast tissue without engaging in exploratory surgery, thus giving women a screening technique that was simple and inexpensive. By 1971, a quarter million women over age thirty-five had been screened. Twenty years later, that number was in the millions.