Treatment of stage I nasopharyngeal carcinoma: analysis of the patterns of relapse and the results of withholding elective neck irradiation.

This is a retrospective analysis of 196 patients with nasopharyngeal carcinoma Stage I (Ho's classification) treated by megavoltage radiation during 1980-1984. The primary target volume included all potential sites of local invasion and the first station lymph nodes at retropharyngeal spaces. Two different dose schedules were used, both gave a total tumor dose biologically equivalent to 65 Gy by conventional fractionation, and both achieved a 5-year actuarial local-recurrence-free survival of 88%. Elective neck irradiation was withheld in all except seven patients. The overall 7-year actuarial survival was 85%, but the relapse-free survival was only 62%. The patterns of relapse, prognostic factors, and treatment complications were analyzed. Eighteen patients (9%) recurred locally. Radical retreatment with radiation achieved complete remission in seven out of fifteen cases. Distant failure occurred in 17 patients (9%). Although 57 (30%) of the 189 patients without elective neck irradiation subsequently showed lymph node involvement, none of the seven regionally-treated patients relapsed. The successful regional salvage rate was 81% overall (46 out of 57 patients), but 90% (44 of 49) for those properly treated with whole neck irradiation. However, the 7-year actuarial survival was lower in patients with nodal relapse than those without (70% versus 87%) because of the associated higher incidence of hematogenous dissemination. The various aspects of treatment, the value of elective neck irradiation in particular, are discussed.