Contralateral Neck Irradiation Can Be Omitted for Selected Lateralized Oral Cancer in Locally Advanced Stage

Area of Science:

• Oncology
• Head and Neck Surgery
• Radiation Oncology

Background:

• Locally advanced oral cavity squamous cell carcinoma (OSCC) poses challenges in treatment planning.
• Contralateral neck failure (cRF) is a critical concern in managing lateralized OSCC.
• Adjuvant irradiation strategies for the neck are debated, particularly regarding contralateral coverage.

Purpose of the Study:

• To evaluate contralateral neck failure rates in patients with well-lateralized advanced OSCC.
• To compare outcomes between unilateral and bilateral neck adjuvant irradiation.
• To determine if omitting contralateral neck irradiation impacts cure rates.

Main Methods:

• Retrospective analysis of 149 patients with lateralized OSCC (2007-2017).
• Inclusion criteria: curative surgery, pT3/4 or pN0-2b, no distant metastasis.
• Exclusion criteria: midline crossing, level 1a involvement, positive extranodal extension (ENE).
• Primary endpoint: 5-year cumulative incidence of cRF.
• Secondary endpoints: CSS, LRRFS, DMFS, cRRFS.

Main Results:

• The 5-year cumulative incidence of cRF was low at 3.6%.
• No significant differences in CSS, LRRFS, DMFS, or cRRFS were found between unilateral and bilateral irradiation groups.
• Contralateral neck recurrence occurred in 5 patients (3.4%), always with simultaneous local recurrence; no isolated cRF was observed.

Conclusions:

• Contralateral neck failure is acceptably low in well-lateralized advanced OSCC with an initially uninvolved contralateral neck.
• Omitting contralateral neck irradiation and adopting active surveillance may be a viable option.
• This approach could potentially maintain cure rates in locally advanced OSCC without compromising outcomes.