Will Screening Mammography in the East Do More Harm than Good?

Abstract

Evidence is insufficient to justify population-based breast cancer screening by mammography for women in Hong Kong and other Asian populations with low breast cancer prevalence.

Cost effectiveness of mammography screening for Chinese women

“…Moreover, nearly all women with mammographydetected DCIS would undergo major excision and potentially disfiguring (physically and psychologically) operations. 13 It is noteworthy that the age-specific incidence pattern after age 40 years is a much slower rising plateau in Hong Kong and is very similar to that observed in Singapore, 50 with a clear cohort effect in which women who were born after 1945 have progressively higher incidence. In our previous study, 11 we also observed that the average annual increase in age-standardized breast cancer incidence was 1.2% from 1973 to 1999 and was driven largely by a cohort effect of westernization from the generation of the postwar migrants, who were the first generation of girls (and particularly adolescent girls) to experience in large numbers the more westernized lifestyle associated with socioeconomic development.…”

“…[6][7][8][9] Although breast cancer is responsible for the majority of new malignancies among Hong Kong Chinese women 10 with a rising incidence, 11 it remains at only approximately 50% of the incidence among Caucasians. 12 Even assuming that the survival benefit of mammog-raphy scales linearly at a lower prevalence at screening, this different epidemiologic burden immediately translates into a reduced positive predictive value, 13 thus casting doubt on the generalizability of effectiveness and efficiency estimates among non-Chinese populations. To derive evidence-based guidance in the East-Asian context, we developed a decision-analytic model to assess the incremental cost effectiveness of an organized screening program.…”

Cancer diagnosis using proteomic patterns

“…A limitation of individual cancer biomarkers is the lack of sensitivity and specificity when applied to large heterogeneous populations [29,32]. Biomarker pattern analysis is an emerging technology aimed at overcoming this limitation.…”

Por que reconsiderar a indicação do rastreamento do câncer de mama?

“…Na falta desse critério, resta a redução da mortalidade por câncer de mama em ensaios clínicos. Essa varia de 0 46 a 20% 50,51 , sendo a estimativa mais mencionada entre 10 e 15% 15 (porém, entre os estudos aleatorizados de maneira adequada, os melhores não apresentaram diferença na mortalidade 15 ). Aceitando a redução de 20% no risco relativo, isso significa uma redução de risco absoluto de apenas 0,1% (a mortalidade por câncer de mama reduz de 5 para 4 mulheres por mil nas rastreadas).…”