Full story: http://bit.ly/Pskpg2 -- A recent study suggests that daily use of the drug tadalafil (Cialis) does not prevent erectile dysfunction for men undergoing radiation therapy for prostate cancer treatment. Deborah W. Bruner from Emory's Nell Hodgson Woodruff School of Nursing and Winship Cancer Institute was principal investigator of the study conducted by the Radiation Therapy Oncology Group's Community Clinical Oncology Program.