The invention: A cytologic technique the diagnosing uterine cancer, the second most common fatal cancer in American women.
The people behind the invention:
George N. Papanicolaou (1883-1962), a Greek-born American
physician and anatomist Charles Stockard (1879-1939), an American anatomist Herbert Traut (1894-1972), an American gynecologist
Cancer in History
Cancer, first named by the ancient Greek physician Hippocrates of Cos, is one of the most painful and dreaded forms of human disease. It occurs when body cells run wild and interfere with the normal activities of the body. The early diagnosis of cancer is extremely important because early detection often makes it possible to effect successful cures. The modern detection of cancer is usually done by the microscopic examination of the cancer cells, using the techniques of the area of biology called “cytology, ” or cell biology.
Development of cancer cytology began in 1867, after L. S. Beale reported tumor cells in the saliva from a patient who was afflicted with cancer of the pharynx. Beale recommended the use in cancer detection of microscopic examination of cells shed or removed (exfoliated) from organs including the digestive, the urinary, and the reproductive tracts. Soon, other scientists identified numerous striking differences, including cell size and shape, the size of cell nuclei, and the complexity of cell nuclei.
Modern cytologic detection of cancer evolved from the work of George N. Papanicolaou, a Greek physician who trained at the University of Athens Medical School. In 1913, he emigrated to the United States.
In 1917, he began studying sex determination of guinea pigs with Charles Stockard at New York’s Cornell Medical College. Papanicolaou’s efforts required him to obtain ova (egg cells) at a precise period in their maturation cycle, a process that required an indicator
of the time at which the animals ovulated. In search of this indicator, Papanicolaou designed a method that involved microscopic examination of the vaginal discharges from female guinea pigs.
Initially, Papanicolaou sought traces of blood, such as those seen in the menstrual discharges from both primates and humans. Papanicolaou found no blood in the guinea pig vaginal discharges. Instead, he noticed changes in the size and the shape of the uterine cells shed in these discharges. These changes recurred in a fifteen-to-sixteen-day cycle that correlated well with the guinea pig menstrual cycle.
“New Cancer Detection Method”
Papanicolaou next extended his efforts to the study of humans. This endeavor was designed originally to identify whether comparable changes in the exfoliated cells of the human vagina occurred in women. Its goal was to gain an understanding of the human menstrual cycle. In the course of this work, Papanicolaou observed distinctive abnormal cells in the vaginal fluid from a woman afflicted with cancer of the cervix. This led him to begin to attempt to develop a cytologic method for the detection of uterine cancer, the second most common type of fatal cancer in American women of the time.
In 1928, Papanicolaou published his cytologic method of cancer detection in the Proceedings of the Third Race Betterment Conference, held in Battle Creek, Michigan. The work was received well by the news media (for example, the January 5,1928, New York World credited him with a “new cancer detection method”). Nevertheless, the publication—and others he produced over the next ten years—was not very interesting to gynecologists of the time. Rather, they preferred use of the standard methodology of uterine cancer diagnosis (cervical biopsy and curettage).
Consequently, in 1932, Papanicolaou turned his energy toward studying human reproductive endocrinology problems related to the effects of hormones on cells of the reproductive system. One example of this work was published in a 1933 issue of The American Journal of Anatomy, where he described “the sexual cycle in the human female.” Other such efforts resulted in better understanding of reproductive problems that include amenorrhea and menopause.
It was not until Papanicolaou’s collaboration with gynecologist Herbert Traut (beginning in 1939), which led to the publication of Diagnosis of Uterine Cancer by the Vaginal Smear (1943), that clinical acceptance of the method began to develop. Their monograph documented an impressive, irrefutable group of studies of both normal and disease states that included nearly two hundred cases of cancer of the uterus.
Soon, many other researchers began to confirm these findings; by 1948, the newly named American Cancer Society noted that the “Pap” smear seemed to be a very valuable tool for detecting vaginal cancer. Wide acceptance of the Pap test followed, and, beginning in 1947, hundreds of physicians from all over the world flocked to Papanicolaou’s course on the subject. They learned his smear/diagnosis techniques and disseminated them around the world.
Impact
The Pap test has been cited by many physicians as being the most significant and useful modern discovery in the field of cancer research. One way of measuring its impact is the realization that the test allows the identification of uterine cancer in the earliest stages, long before other detection methods can be used. Moreover, because of resultant early diagnosis, the disease can be cured in more than 80 percent of all cases identified by the test. In addition, Pap testing allows the identification of cancer of the uterine cervix so early that its cure rate can be nearly 100 percent.
Papanicolaou extended the use of the smear technique from examination of vaginal discharges to diagnosis of cancer in many other organs from which scrapings, washings, and discharges can be obtained. These tissues include the colon, the kidney, the bladder, the prostate, the lung, the breast, and the sinuses. In most cases, such examination of these tissues has made it possible to diagnose cancer much sooner than is possible by using other existing methods. As a result, the smear method has become a basis of cancer control in national health programs throughout the world.
See also Amniocentesis; Birth control pill; Mammography; Syphilis test; Ultrasound.
