This article discusses issues of ethical concern in the conduct of a prospective, cluster randomised controlled trial for evaluating effectiveness of screening by clinical breast examination for downstaging of breast cancer, and in reducing mortality from the disease, in comparison to no screening. This trial was conducted in Mumbai, India, over 20 years, from May 1998 to March 2019. Trained primary health workers provided health education, visual inspection of cervix and clinical breast examination in the screening arm. Women in the control arm were provided only health education and not provided any intervention, though screening mammography is an established, standard procedure, which is also available in Mumbai; the risks of not having the examination, and the benefits of having the examination (mammography or clinical examination by health worker), in terms of early detection and hence the possibility of starting early treatment, were not explained; furthermore, there were several differences in the English and Marathi informed consent forms.