The outcome of postoperative radiation therapy following plastic surgical resection of recurrent ear keloid: a single institution experience.

Background: Ear keloids are abnormal continuously growing healing process following cutaneous injury. Surgical excision is the standard treatment strategy; however, 50-80% of cases develop recurrence. Adjuvant radiotherapy (RT) is commonly offered with a marked decrease in the recurrence rate. The variation in RT protocols used in different studies leads to a bias of results analysis. The aim is to present our experience of using surgical excision with postoperative radiotherapy for recurrent ear keloids. Also, studying different variables especially dose and keloid size that affects recurrence rate. Radiotherapy complications were reported and assessed.

Patients And Methods: Keloids between 2006 and 2021 were retrospectively reviewed. Fifty-five ear keloids out of 83 cases who received RT after surgical excision were included in the study. Different dose regimens including 13 Gy/1fx, 8 Gy/1fx, 10 Gy/2fx, 15 Gy/3fx, and other fractionated regimens were used. The Median follow-up period was 35 months. Recurrence-free rate (RFR), side effects, and prognostic factors were assessed.

Results: The overall 2-year RFR was 88 ± 5%. The 2-year RFR was 83 ± 8% for dose regimens with biological effective dose (BED) ≤ 40 and 92 ± 5% for regimens with BED > 40 Gy with an insignificant p value. The 2-year RFR was 74 ± 10% compared to 97 ± 3% for keloids > 2 cm and keloids ≤ 2 cm respectively (p value 0.02). The higher dose used for keloids with > 2 cm size significantly improved RFR. The orthovoltage therapy showed marginally better 2-year RFR compared to electron beam therapy; however, statistically insignificant (p value 0.09). The side effects were minimal with no reported second malignancy or serious G3-4 complications.

Conclusion: Excision followed by RT is a safe and effective treatment for recurrent ear keloids. Low and modest radiation doses are effective; however, a higher dose is recommended for keloids > 2 cm. We recommend a prospective larger-scale study to test the effect of dose and keloid size on the treatment results.