For cancer of the uterine cervix, the most effective case-finding device—particularly in large populations—is the cytologic, or cell, examination popularly known as the "Pap test." With the aid of grants from the Health, Education, and Welfare Department's Cancer Control Program, hospitals in 35 States, the District of Columbia and the Commonwealth of Puerto Rico now provide cervical examinations on a routine basis to all their in-patient and out-patient clients. There are now 140 such projects, which have made more than a million cytology examinations through which cancer was found in 7,000 patients. Also, by the spring of 1968, 750,000 women had been similarly screened through the office-detected cervical cancer program of the American Academy of General Practice, which now embraces about 5,000 physicians in 40 States and the District of Columbia. In this group, 1,700 carcinomas were detected.
The usefulness of cervical cytology as a screening device depends largely on the availability of cytotechnologists and cytotechnicians in the laboratories. Federal funds devoted to training these people support some 550 students a year in about 70 schools throughout the country.
Computer processing of data from large screening projects is helping to speed up the recovery of information, prevent duplication, assist in follow-up, and enable patients to use special equipment or facilities possessed by any of the cooperating hospitals. This effort, begun in New York City in 1966, is now in successful operation and will be extended to other cities, beginning with Philadelphia.
The Cancer Control Program is also sponsoring studies to make exfoliative cytology more effective in detecting oral cancers by doctors and dentists. Slides carrying specimens from the oral cavity are being exchanged among experts to determine the extent to which uniform readings can be obtained.
Better results in detecting cancer of the colon and rectum by examination through a lighted tube can be expected with a new type of flexible proctosigmoidoscope now being tested at several medical centers. The instrument is designed to reach more remote segments of the colon than are reached by the rigid type.
Continuous efforts are being made to obtain better results in detecting breast cancer. The techniques being constantly developed and used employ X-rays, heat sensing devices, and ultrasound. The Egan X-ray technique of mammography has been taught to more than 1,800 radiologists and technologists since 1964 as an aid in bringing patients to earlier diagnosis and treatment. This technique has the advantages of being reproducible, acceptable to the patient, safe, non-traumatic, objective, and highly accurate; it also provides a means of studying the natural history of the disease.