Rates of osteoradionecrosis in resected oral cavity cancer reconstructed with free tissue transfer in the intensity‐modulated radiotherapy era

Abstract

Background: Resected oral cavity carcinoma defects are often reconstructed with osteocutaneous or soft-tissue free flaps, but risk of osteoradionecrosis (ORN) is unknown. Methods: This retrospective study included oral cavity carcinoma treated with free-tissue reconstruction and postoperative IMRT between 2000 and 2019.Risk-regression assessed risk factors for grade ≥2 ORN. Results: One hundred fifty-five patients (51% male, 28% current smokers, mean age 62 ± 11 years) were included. Median follow-up was 32.6 months (range, 1.0-190.6). Thirty-eight (25%) patients had fibular free flap for mandibular reconstruction, whereas 117 (76%) had soft-tissue reconstruction.Grade ≥2 ORN occurred in 14 (9.0%) patients, at a median 9.8 months (range, 2.4-61.5) after IMRT. Post-radiation teeth extraction was significantly associated with ORN. One-year and 10-year ORN rates were 5.2% and 10%, respectively.

Prevention and Management of Osteoradionecrosis in Patients With Head and Neck Cancer Treated With Radiation Therapy: ISOO-MASCC-ASCO Guideline

“…Eighty publications were identified on the basis of the search strategy described in the Methods section. Of these, six were RCTs, [10][11][12][13][14][15] 14 were prospective studies, 3,[16][17][18][19][20][21][22][23][24][25][26][27][28][29] and 60 were retrospective studies. The identified trials were published between 2004 and 2023.…”

“…84,85 However, rates of ORN have decreased over time, which is thought to be at least in part due to the increasing use of IMRT. 3,28 The largest study that has examined dosimetry parameters for bone avoidance was a study of 1,259 patients with HNC treated with chemoradiation, which showed that limiting no more than 30% of the mandible to receive a dose of 35 Gy or more confers a <5% risk of ORN for patients undergoing pretreatment dental extractions. For patients without pretreatment dental extractions, limiting no more than 30% of the mandible to receive a dose of 42 Gy or more confers a <5% risk of ORN.…”