Introduction

To report the efficacy and safety of high-dose-rate (HDR) plesiotherapy using a customized applicator for sebaceous carcinoma of the eyelid in a patient with contraindications to interstitial brachytherapy.

Material and methods

A 84-year-old female, ECOG 0, was diagnosed with localized sebaceous gland carcinoma (SGC; stage IB, T2aN0M0), of the left upper eyelid. The patient was not cleared for surgery or interstitial brachytherapy; HDR plesiotherapy was given as 14 fractions 3.5 Gy per fraction, twice daily, over 11 days, with a three-day break after seven fractions. Surface mold applicator was created using a thermoplastic mask, and plastic catheters were secured with dental putty over the mask; the mask served as both a bolus and spacer. High-risk clinical target volume (HR-CTV) comprised the tumor and involved lateral canthus, while intermediate-risk clinical target volume (IR-CTV) consisted of 5 mm around HR-CTV. Eyelid scarring excluded corneal shielding. Due to pre-existing cataract, a higher left lens dose allowed delivery of definitive doses.

Results

HR-CTV D₉₀, IR-CTV D₉₅, lens D_0.1cc, and cornea D_0.1cc were 3.74 Gy, 2.66 Gy, 1.81 Gy, and 3.23 Gy, respectively, resulting in EQD₂ (α/β = 10 for tumor, α/β = 3 for normal tissue; no interfraction repair for tumor assumed) of 73.9 Gy, 46.4 Gy, 24.4 Gy, and 56.3 Gy, respectively. According to the patient’s preference, no elective neck management was performed. The patient developed only acute grade 2 blepharitis and conjunctivitis, with no signs of radiation keratitis. At 2-year follow-up, she developed an ipsilateral neck recurrence, which was otherwise asymptomatic. No salvage or palliative treatment was administered. No late radiation-induced toxicity was documented. At five years, local control was maintained.

Conclusions

This case demonstrates that HDR plesiotherapy is a feasible option for local control of the eyelid SGC with a favorable toxicity profile, even when corneal shielding is not possible.