Retropharyngeal node dissection during total pharyngolaryngectomy for hypopharyngeal cancer

To clarify the efficacy of retropharyngeal (RP) node dissection for hypopharyngeal cancer (HPC). From 1990 to 1997 (Period I), we examined the RP area preoperatively using computed tomography (CT) and magnetic resonance imaging (MRI), and dissected this region during total pharyngolaryngectomy (TPL) when lymph node shadows were identified. From 1998 to 2001 (Period II), we dissected this region during TPL for all patients displaying stage IV HPC or invasion of the oropharyngeal wall. Outcomes were investigated for patients with positive RP nodes identified during TPL or postoperatively. From 1990 to 2001, positive RP nodes were identified in 41 patients during TPL and in 13 patients, postoperatively. These 54 patients represented 14.8% of all patients with HPC in our hospital. Tumors of the pyriform sinus with oropharyngeal invasion and tumors of the posterior wall both displayed high risk of positive RP nodes. Frequencies of RP nodes were: stage I, 3.0%; stage II, 10.3%; stage III, 9.8%; stage IV, 19.2%. Although preoperative imaging revealed positive RP nodes for 32 patients, positive nodes were too small nodes to detect on CT or MRI in nine patients. No significant differences in survival were noted between Periods I and II. However, 11 of the 41 patients with positive RP nodes during TPL survived >2 years without disease, while only one of the 13 patients with positive RP nodes, identified postoperatively, survived >2 years. Patients with positive RP nodes displayed poor local control rate. RP dissection did not improve survival rate.