HDR-BT with 3D-printed individual applicators for skin BCC in the H&N area – initial results.
OC-0634
Abstract
HDR-BT with 3D-printed individual applicators for skin BCC in the H&N area – initial results.
Authors: Artur Chyrek1, Wojciech Burchardt1,2, Grzegorz Bielęda3,2, Adam Kluska1, Adam Chicheł1
1Greater Poland Cancer Centre, Brachytherapy Department, Poznań, Poland; 2University of Medical Sciences, Electroradiology Department, Poznań, Poland; 3Greater Poland Cancer Centre, Medical Physics Department, Poznań, Poland
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Purpose or Objective
In 2020 after developing the process of preparing applicators in 3D printing technology, we started using this technique to treat skin cancers in anatomically difficult locations with high-dose-rate brachytherapy (HDR-BT). This retrospective study aims to evaluate the initial efficacy and toxicity of this method for skin basal cell carcinoma (BCC) located in challenging regions of the head & neck area.
Material and Methods
Between 06.2020 and 03.2022 20 patients with 25 BCC tumors were treated. The exact process of making the applicator (Fig. 1) and planning the treatment was presented in our previous report. The response rate (RR) to the treatment and early toxicity was assessed four weeks after finishing HDR-BT, then patients were evaluated every 3-6 months for the late toxicity and local control (LC).
Fig. 1 – Individual 3D-printed applicator for treating the BCC located on the nose.
Results
There were 15 women and 5 men treated in the mean age of 76,9 years. Among 25 tumors 19 were classified as T1 (76%), 3 as T2 (12%) and 3 as T3 (12%) according to UICC/AJCC TNM v.7. Lesions were located on the nose (76%), ear (12%) and peri-orbitally (12%). The HDR-BT were performed as the primary treatment for 14 lesions (56%) and as the salvage after previous surgery in remaining 11 (44%). All tumors were classified to be at the high risk of recurrence according to NCCN. The mean follow-up (counted from the end of HDR-BT) was 14 months (median 13 m.; 6,2 – 26,9). All tumors received planned dose of 42 – 45 Gy in 6 – 11 fractions within overall treatment time of 6 – 27 days. During the follow up both RR and LC were 100%. Acute skin toxicity presented as erythema (36%), patchy desquamation (4%), confluent desquamation (8%) and tumor disintegration with bleeding (40%). Late skin toxicity resulted in redness, depigmentation, or discoloration (44%) (fig. 2) and small telangiectasia (4%).
Fig. 2 – BCC T1 tumor located on the nose before the HDR-BT, and depigmentation visible 23 months after the treatment.
Conclusion
This report shows very good preliminary results in terms of both high local tumor control and low toxicity for skin BCC obtained with superficial HDR-BT with 3D printed custom-made applicators.