237 Editorial

The paper in the present issue of the APJCP by Mandal and his colleagues offers a disturbing contrast to generally positive conclusions of the recent special article by Breen et al (2001) on progress in cancer screening in the USA. The underlying differences in basic assumptions are of essential significance if we are to advocate national screening programs in Asia. A simple comparison points to major inequality between countries which is also a feature within the various sectors of communities. To concentrate first on the good news, national health surveys for 1987, 1992 and 1998 in the United States demonstrate that use of all screening modalities, including Pap smears, mammography, fecal occult blood tests (FOBTs), sigmoidoscopy and digital rectal examination (DRE), increased over the period. However, patterns of change differed, especially with he racial/ethnic groups, those with lower income and less education consistently demonstrating lower prevalence of use. A lack of health insurance or a usual source of care were quoted as important factors in the latter. The availability of relatively simple methods for early detection of cancer in the upper alimentary canal, stomach, colorectum, cervix and perhaps breast, means theoretically that much could also be achieved with screening in the developing world. In Asia, fo example, these cancers account for large proportions of the total cancer burden (see the Table), naturally with considerable country variation. The stress would thus need to be appropriately selected in line with the available registration data and financial resources. With regard to reports from Asia in this area, while there is a major problemwith non-participation of oral cancer atrisk subjects (Warnakulasuriya and Johnson, 1996), screening can be very beneficial as evidenced by results with 60 year old residents in a city in Japan, very good predictive values being reported (Ikeda et al., 1995).The efficacy of gastric cancer screening has been reviewed by Yoshida and Saito (1996). With the occult blood approach, risk of malignant tumor development in the colon may be halved (Saito et al., 1995) and a survival rate for five years of 87% as opposed to 57% for symptomatic cases has been reported (Shida et al., 1996). With FOBT alone, sensitivities of 90% for 1 year, 83% for 2 and 71% for 3, have been reported, with a specificity of 95.6% (Nakama et al., 1996). It has been estimated that 91 % of cervical cancers can be prevented by screening (Hristova and Hakama, 1997) and results from Japan also point to major benefit. In fact, occult blood tests for colorectal and urogenital cancers could be married to superficial observation for skin and palpation for