ARM II: Patients undergo radiotherapy (IMRT) 1.8 Gy, 5 days a week over 6 weeks for a total of 28 treatments and 50.4 Gy, in the absence of disease progression or unacceptable toxicity. IMRT starts within 14 days of registration if no postoperative adjuvant chemotherapy, otherwise within 14 days of the completion of the chemotherapy.