Patient-specific 3D-printed HDR surface brachytherapy for basal cell carcinoma in older patients: prospective feasibility and imaging response.

BACKGROUND

Basal cell carcinoma (BCC) is common in older adults, many of whom are poor surgical candidates, especially for curved and cosmetically sensitive facial sites. High-dose-rate (HDR) surface brachytherapy is effective, but standard flat applicators may fit poorly and increase dose heterogeneity. Patient-specific 3D-printed applicators could improve conformity, yet geriatric BCC data are limited.

OBJECTIVE

To assess the feasibility and 12-month outcomes of personalized 3D-printed HDR surface brachytherapy in geriatric patients with BCC.

METHODS

In this prospective single-arm study, 15 patients aged ≥65 years with histologically confirmed BCC (predominantly facial) who were unsuitable for surgery received HDR surface brachytherapy using custom 3D-printed applicators. Treatment delivered 51 Gy in 17 fractions with CT-based planning. Repeat CT imaging evaluated applicator fit/reproducibility and target coverage. Acute skin toxicity was graded by RTOG. At 12 months, response was assessed clinically and dermoscopically; cosmesis and quality of life (Dermatology Life Quality Index [DLQI]) were recorded.

RESULTS

All patients completed treatment. Positioning was highly reproducible (mean setup error <1 mm) with >90% target dose coverage. At 12 months, all lesions achieved complete remission, with no local recurrence on dermoscopy. Acute reactions were mostly mild (73% grade 1), with 13% grade 2 and 13% grade 3; no grade 4 toxicity or serious adverse events occurred. Cosmesis was favorable, and DLQI improved (mean, 10.5 pre-treatment vs 2.9 at 1 year; P < .01).

CONCLUSIONS

Personalized 3D-printed HDR surface brachytherapy appears feasible and well tolerated in this small, single-center cohort of older patients with BCC, with favorable 1-year local control and quality-of-life improvement when surgery is contraindicated. However, the limited sample size and single-center design represent limitation, and the observed benefit should be regarded as suggestive rather than definitive.