Interstitial Brachytherapy for Lip Cancer: Technical Aspects to Individualize Treatment Approach and Optimize...

Area of Science:

• Oncology
• Radiation Oncology
• Surgical Oncology

Background:

• Squamous cell carcinoma of the lip is a common malignancy.
• Primary radiation therapy, specifically interstitial brachytherapy (IBT), is a viable treatment option for early-stage disease.
• Optimizing technical aspects of IBT is crucial for maximizing treatment efficacy and minimizing side effects.

Purpose of the Study:

• To detail the technical considerations for performing interstitial brachytherapy (IBT) for lip cancers.
• To evaluate the outcomes of IBT in terms of local tumor control, toxicity, and cosmesis.
• To provide guidance on patient selection, procedural techniques, and dosimetric planning for lip IBT.

Main Methods:

• Catheter placement across the tumor extent with a 5 mm margin.
• Custom mouthpiece fabrication for normal tissue sparing.
• CT-based treatment planning with dose objectives (GTV D90% ≥ 90%, minimize V150%) and high-dose-rate delivery.

Main Results:

• 100% local tumor control was achieved in 10 patients with primary or recurrent lip squamous cell carcinoma.
• No acute grade ≥4 or late grade ≥2 toxicity was observed.
• Cosmesis scores were uniformly graded as good to excellent.

Conclusions:

• Interstitial brachytherapy (IBT) is an effective treatment for lip squamous cell carcinoma, yielding high tumor control rates.
• Meticulous attention to technical details, including patient selection, catheter placement, and dosimetry, is essential for success.
• IBT offers favorable functional and esthetic outcomes with a low toxicity profile for lip cancer patients.