Breast cancer is the most important cancer affecting women. It is by far thecommonest cancer among Egyptian women and represents 37% of all femalecancers.Aim: assess different risk factors of breast cancer, assess the knowledge about riskfactors and early detection methods of breast cancer and identify the validity(sensitivity; specificity; predictive values; accuracy) and agreement of breast light inscreening of breast cancer compared to mammography and biopsy if available.Subjects and Methods: Hospital-based cross sectional study was conducted at NationalCancer Institute, Cairo University in the period from 20 April 2012 till 20 February 2014.The study tools included: ١- interviewer administrated questionnaire. It was prepared toget some socio-demographic characteristics, and risk factors of breast cancer, assessknowledge about risk factors of breast cancer and early detection measures of breastcancer. ٢- Evaluation of breast using breast light technique. ٣- Mammographic andultrasound evaluation of the breast. ٤- Pathological results of specified cases if biopsy orsurgical excision was performed were retrieved from patient’s records.Results: The study involved 310 females. The frequency of breast cancer more commonamong: old age, illiterate cases, women who had early menarche and later menopause,females use of hormonal contraception, women had first birth at age ≥ 30 years,women’s sleep <7 hours/day, women with total physical activity <9 MET-h/week. Only27.1 % of the participants knew about early detection measures of breast cancer. Breastself-examination was known by 11% of the participants as a method of early detection.Breast illumination method had sensitivity of 93.0%, specificity of 73.7%, Positivepredictive value (PPV) of 91. 4%, negative predictive value (NPV) of 77.8% and totalaccuracy of breast illumination method was 88.2% in detection of breast cancer. Breastillumination and mammogram were concordant in 89.4%.The study concluded that. Breast-light was highly effective in identifying breastcancer and it is considered to be an important tool in the early detection of breastcancer. The study recommended the need for health education to improve awarenessabout breast cancer and early detection measures of breast cancer. Use of breastillumination method in primary health care centre and by women at home in particularit would be of great assistance for early detection of breast cancer.