Postoperative Radiotherapy in Advanced Stage Squamous Cell Carcinoma Requiring Maxillectomy

Area of Science:

• Oncology
• Surgical Oncology
• Radiation Oncology

Background:

• Maxillary gingival and hard palate squamous cell carcinoma (SCC) are aggressive cancers.
• Maxillectomy is a primary surgical treatment, but adjuvant therapy decisions require careful consideration.
• Tumor size and bone invasion are critical factors influencing treatment outcomes.

Purpose of the Study:

• To determine if postoperative radiotherapy (PORT) improves survival in patients with pT4aN0 maxillary SCC after maxillectomy.
• To investigate the impact of tumor size on the efficacy of PORT.

Main Methods:

• Retrospective analysis of the National Cancer Database (2004-2019).
• Included adult patients with treatment-naive, margin-negative pT4aN0 SCC of the maxillary gingiva or hard palate who underwent maxillectomy and neck dissection.
• Used inverse probability weights and multivariable Cox proportional hazards models, with subgroup analysis based on tumor size.

Main Results:

• 416 patients were included; 49.3% received PORT.
• PORT was associated with a 50% improvement in survival (aHR, 0.50; 95% CI, 0.32-0.81).
• Improved survival with PORT was observed for tumors ≥2cm (aHR, 0.47; 95% CI, 0.29-0.77), but not for tumors <2cm (aHR, 1.15; 95% CI, 0.33-4.08).

Conclusions:

• Most patients with pT4aN0 bone-invading maxillary SCC benefit from PORT.
• Adjuvant PORT may not be necessary for smaller tumors (<2cm), suggesting bony invasion alone is insufficient for escalation.
• Treatment decisions for maxillary SCC should consider tumor size in addition to bone invasion.