Intraoperative Radiation Therapy Reduces Local Recurrence Rates in Patients With Microscopically Involved Circumferential Resection Margins After Resection of Locally Advanced Rectal Cancer. - Alberda, Wijnand J.; Verhoef, Cornelis; Nuyttens, Joost J.; van Meerten, Esther; Rothbarth, Joost; de Wilt, Johannes H.W.; Burger, Jacobus W.A. (International Journal of Radiation Oncology, Biology, Physics, 2014)