§ Yvette Cooper
[holding answer 10 April 2002]: The International Agency for Research on Cancer (IARC) of the World Health Organisation (WHO) recently evaluated the evidence on breast screening. The results of the evaluation were announced on Tuesday 19 March this year and confirmed earlier advice as to the effectiveness of breast screening.
IARC concluded that trials have provided sufficient evidence for the efficacy of mammography screening of women between 50 and 69 years and that the reduction in mortality from breast cancer among women who chose to participate in screening programmes was estimated to be about 35 per cent.
The working group which consisted of 24 experts from
11 countries also considered the earlier criticisms of the trials and concluded that many of these were unsubstantiated, and the remaining deficiencies were judged not to invalidate the trials' findings.
§ Mr. Burns
To ask the Secretary of State for Health (1) what assessment he has made of the extent of mastectomies carried out as a precaution on women who have had a tumour detected by breast screening but were of a kind that may never develop into cancer; 
(2) what proportion of women who undergo breast screening have had mastectomies carried out as a result of the screening in the last three years. 
§ Yvette Cooper
[holding answer 10 April 2002]: One in five breast cancers detected through screening will be found when still within the milk duct. This is called Ductal Carcinoma In Situ (DCIS). DCIS is difficult to treat as it is not known which women might progress rapidly to invasive cancer and need extensive treatment, and which women could be managed more conservatively. Detecting DCIS does not necessarily lead to mastectomy. Treatment options are always discussed with women and most women will be offered a choice between mastectomy and less drastic treatment.923W
Of the 9,525 cancers detected by the breast screening programme in the UK in 1999–2000, 2,009 were DCIS. 29 per cent. of non-invasive screen-detected breast cancers resulted in mastectomy'.
NHS Cancer Screening Programmes are funding a study to improve quality of care for women with screen detected DCIS. The results of the study will lead to an evidence-based review on the approach taken to the management of women with DCIS. The study is due to report in 2004.1British Association of Surgical Oncologists, May 2001