What is your approach to postoperative radiation for intraductal carcinoma of the parotid?

I would consult a pathologist specializing in head and neck cancer. Low grade intraductal ca is similar histologically and clinically to intraductal ca in-situ of the breast, with myoepithelial markers and ductal differentiation, and requires surgery alone. On the other hand, high grade ductal carcinoma is morphologically similar to ductal breast ca but may behave more aggressively than breast cancer and requires post-op therapy. Other histologies that need to be differentiated are high grade carcinoma ex-pleomorphic adenoma and, if cystic components and acini are involved in addition to the ducts, adenoid cystic ca. For the high grade histologies, postop irradiation should be to the tumor bed, facial lymphatics, and levels Ib-III nodes.