Benefit of postoperative radiotherapy for early tumors with single ipsilateral lymph node metastasis.

OBJECTIVES/HYPOTHESIS: Indication for postoperative radiotherapy in patients with locally circumscribed tumors (pT1-pT2) and a single ipsilateral lymph node metastasis (pN1) is debatable. The aim of this study was to evaluate the oncological long-term outcome of patients with pT1-pT2 pN1 squamous cell carcinoma (SCC) of the oral cavity, the oropharynx, and the hypopharynx without extracapsular spread (ECS) after a margin-negative surgical resection, who either received or did not receive postoperative (chemo)radiotherapy. STUDY DESIGN: Retrospective case series. METHODS: The oncological outcome of patients with pT1-pT2 pN1 SCC without ECS was evaluated retrospectively. All patients underwent primary tumor resection that included transoral laser microsurgery and neck dissection at an academic tertiary referral center. RESULTS: Of 65 identified patients treated between 1986 and 2015 (18 oral cavity, 30 oropharynx, 17 hypopharynx), 21 (32%) received postoperative radiotherapy, and 44 (68%) were treated by surgery alone. The group of patients receiving postoperative treatment showed a significantly superior 5-year disease-specific (94.4% vs. 73.2%, P = .029) and recurrence-free survival (85.2% vs. 43.2%, P = .002), as well as a higher local control rate (90.2% vs. 64.9%, P = .042). The overall survival was 71.4% vs. 62.6% (P = .53). The mean follow-up was 80.7 months. CONCLUSIONS: Patients with locally circumscribed carcinomas and a single ipsilateral ECS-negative lymph node metastasis seem to benefit from postoperative radiotherapy. LEVEL OF EVIDENCE: 4 Laryngoscope, 130:E530-E538, 2020.