12-05-2025
Oral Cavity Cancer: Omitting Neck RT Safe in Some Patients
In patients with early-stage oral cavity carcinoma and a low risk for regional recurrence, omitting elective neck irradiation during postoperative radiotherapy was associated with low rates of regional failure and good locoregional control, according to the results of a recent multicenter study.
METHODOLOGY:
Elective nodal irradiation is standard in postoperative radiotherapy in patients with oral cavity carcinoma but may expose patients to unnecessary toxicity, particularly when the risk for regional recurrence is low.
Researchers analyzed outcomes from 264 patients from 12 Dutch radiotherapy centers between 2010 and 2019, who had undergone surgery with en bloc neck dissection and had pathologically node-negative (pN0) necks.
Patients received postoperative radiotherapy either to the primary tumor only (n = 118) or to the primary tumor bed and neck (n = 146).
Radiation doses varied based on margin status and risk factors.
The primary endpoint was regional failure. Secondary endpoints were local failure, overall survival, and late toxicity (> 3 months posttreatment).
TAKEAWAY:
Overall, nine regional recurrences (3.4%) occurred — four (3.39%) in the tumor bed–only group and five (3.42%) in the combined tumor and neck irradiation group.
After a median follow-up of 5 years, the 5-year regional control rate was 96% in both groups. Lymph node yield from neck dissection was the only factor associated with improved regional control (hazard ratio, 0.46). Regional recurrences were mostly isolated.
Local control at 5 years was also similar at 92% with tumor bed–only radiotherapy compared with 91% with combined tumor and neck irradiation. Overall survival at 5 years was 80% with tumor bed–only radiotherapy and 78% with the combination. The incidence of developing a second primary tumor was not significantly different between the two groups (16% vs 12%, respectively; P > .05).
.05). Late toxicity was significantly higher among patients in the combination group. Grades 2-3 dry mouth was observed in 31% of those who received neck irradiation compared with 15% in those who did not (odds ratio [OR], 4.93). Similarly, grades 2-3 swallowing difficulties occurred in significantly more patients who underwent neck irradiation — 61% vs 19% of patients (OR, 5.29).
IN PRACTICE:
'The study showed that patients irradiated to the primary tumor bed only had the same excellent regional control compared to those irradiated to the primary tumor bed and the operated neck site, with significantly lower incidence of late grade 2-3 xerostomia and dysphagia,' the authors wrote. 'Elective irradiation of the pN0 neck can safely be omitted following local resection with en bloc neck dissection in [oral cavity carcinoma] patients who require adjuvant radiotherapy to the primary tumor bed only based on local pathological risk factors,' they added.
SOURCE:
The study, led by B. Kreike, Radiotherapiegroep, Arnhem, the Netherlands, was published online in Radiotherapy and Oncology .
LIMITATIONS:
Limitations included retrospective design and a low number of regional recurrence events. Additionally, variability in toxicity reporting could have influenced results.
DISCLOSURES:
The authors did not declare any funding information and reported having no relevant conflicts of interest.
