Oral cavity cancer. Patient with a pT. 2N. 0M. 0 carcinoma of the left lateral border of tongue treated with postoperative radiation therapy for close margin and perivascular- perineural invasion. Ipsilateral technique using three ports: anterior, left posterior oblique and left lateral. Green line: PTV1, treated to 60 Gy; blue line: PTV2 including ipsilateral Ib, II and III node levels, treated to 50 Gy; cyan line: contralateral parotid, yellow line: contralateral submandibular; mean dose to the right parotid 8 Gy, mean dose to the submandibular gland 20 Gy.