Pathological distribution of positive lymph nodes in patients with clinically and radiologically N0 oropharyngeal carcinoma: implications for IMRT treatment planning.

Background: We identified involved lymph node groups in patients with oropharyngeal carcinoma and radiologically N0 disease, aiming to define the clinical target volume, and to assess the negative predictive value of CT neck and correlate it to the tumor site, stage, and grade.

Methods And Materials: Between 1988 and 2000, we evaluated 53 patients who satisfied all of the following criteria: 1) oropharyngeal carcinoma diagnosis; 2) NO stage based on CT; 3) no prior treatment; and 4) primary surgical resection including ipsi-lateral neck dissection. The pathology reports were reviewed to identify the exact site of lymph node involvement.