Outcomes after definitive surgery for mandibular osteoradionecrosis

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

PURPOSE

To provide evidence-based recommendations for prevention and management of osteoradionecrosis (ORN) of the jaw secondary to head and neck radiation therapy in patients with cancer.

METHODS

The International Society of Oral Oncology-Multinational Association for Supportive Care in Cancer (ISOO-MASCC) and ASCO convened a multidisciplinary Expert Panel to evaluate the evidence and formulate recommendations. PubMed, EMBASE, and Cochrane Library databases were searched for randomized controlled trials and observational studies, published between January 1, 2009, and December 1, 2023. The guideline also incorporated systematic reviews conducted by ISOO-MASCC, which included studies published from January 1, 1990, through December 31, 2008.

RESULTS

A total of 1,539 publications were initially identified. There were 487 duplicate publications, resulting in 1,052 studies screened by abstract, 104 screened by full text, and 80 included for systematic review evaluation.

RECOMMENDATIONS

Due to limitations of available evidence, the guideline relied on informal consensus for some recommendations. Recommendations that were deemed evidence-based with strong evidence by the Expert Panel were those pertaining to best practices in prevention of ORN and surgical management. No recommendation was possible for the utilization of leukocyte- and platelet-rich fibrin or photobiomodulation for prevention of ORN. The use of hyperbaric oxygen in prevention and management of ORN remains largely unjustified, with limited evidence to support its practice.Additional information is available at www.asco.org/head-neck-cancer-guidelines.

Risk Factors for Infection Recurrence After Surgical Resection of Advanced Stage Osteonecrosis of the Mandible

BACKGROUND

Advanced stage osteoradionecrosis (ORN) and medication-related osteonecrosis of the jaw (MRONJ) are challenging disease entities requiring multimodal therapy including surgical resection. However, risk factors associated with infection recurrence are poorly understood.

PURPOSE

The purpose of this study was to identify risk factors associated with infection recurrence following resection of advanced stage ORN or MRONJ of the mandible.

STUDY DESIGN, SETTING, SAMPLE

This was a retrospective cohort study including patients who underwent segmental mandibulectomy for management of ORN or MRONJ between 2016 and 2021 at the authors' institution. Subjects who did not have margin viability data were excluded.

PREDICTOR/EXPOSURE/INDEPENDENT VARIABLE

The primary predictor variable was viability of resection margins on histopathologic analysis (viable or nonviable). Secondarily, other risk factors categorized as demographic (age, sex, race), medical (comorbidities), and perioperative (reconstructive modality, antibiotic duration, microbiological growth) were evaluated.

MAIN OUTCOME VARIABLE

The primary outcome variable was time to infection recurrence defined as time from surgical resection to clinical diagnosis of a fistula tract, abscess, or persistent inflammatory symptoms necessitating surgical intervention.

COVARIATES

Not applicable.

ANALYSES

Descriptive and bivariate statistics were used to identify associations between risk factors and time to infection recurrence. A significance level of P ≤ .05 was considered significant.

RESULTS

The cohort consisted of 57 subjects with a mean age of 63.3 ± 10.0 years (71.9% Male, 75.4% White) treated for ORN (47.4%) or MRONJ (52.6%). A total of 19/57 (33%) subjects developed a recurrence of infection with 1 and 2 year survival of 75.8 and 66.2%, respectively. Nonviable resection margins were associated with earlier time to infection recurrence (P ≤ .001, hazard ratio (HR) = 11.9, 95% confidence interval (CI) = 3.84 to 36.7) as was younger age (P = .005, HR = 0.921, 95% CI = 0.869 to 0.976) and atypical pathogen growth on culture (P = .002, HR = 8.58, 95% CI = 2.24 to 32.8).

CONCLUSIONS AND RELEVANCE

Histopathologic margin viability was associated with earlier time to infection recurrence following resection of advanced stage ORN or MRONJ of the mandible. Additional studies are needed to identify interventions that may improve outcomes in this demographic.

Evaluation of Anterolateral Thigh Fascia Lata Rescue Flap for Mandibular Osteoradionecrosis

Importance

Mandibular osteoradionecrosis (ORN) is a progressive disease that can be difficult to treat. Conservative measures often fail, while conventional definitive management requires a morbid segmental resection with osteocutaneous reconstruction. Evidence of the anterolateral thigh fascia lata (ALTFL) rescue flap technique's safety, effectiveness, and long-term outcomes is needed.

Objective

To determine the long-term outcomes of the ALTFL rescue flap procedure for treating patients with mandibular ORN.

Design, Settings, and Participants

This was a retrospective medical record review performed at a single tertiary-level academic health care institution with patients who were appropriate candidates for the ALTFL procedure to treat mandibular ORN from March 3, 2011, to December 31, 2022. Data analyses were performed from January 1 to March 26, 2023.

Main Outcomes and Measures

Patient characteristics, preoperative radiographic Notani staging, intraoperative defect size, length of stay, complication rates, and clinical and radiographic findings of progression-free intervals.

Results

The study population of 43 patients (mean [SD] age, 66.1 [47-80] years; 24 [55.8%] male individuals) included 52 cases of mandibular ORN. The preoperative Notani staging of the study population was known for 46 of the 52 total cases: 11 cases (23.9%) were stage I; 21 (45.7%), stage II; and 14 (30.4%), stage III. The mean defect area was 20.9 cm2. Successful arrest of ORN disease progression was noted in the clinical and radiographic findings of 50 of the 52 (96.2%) cases, with only 2 (3.8%) cases subsequently requiring fibular free flap reconstruction. The major complication rate was 1.9% (1 case). Clinical and radiographic progression-free intervals were assessed, and no statistically significant differences were noted between Notani staging groups (log-rank P = .43 and P = .43, respectively); ie, patients with stage III disease had no significant difference in risk of clinical (HR, 0.866; 95% CI, 0.054-13.853) or radiographic (HR, 0.959; 95% CI, 0.059-15.474) progression vs those with stage I disease. Weibull profiling revealed 96.9%, 94.6%, and 93.1% successful mandibular ORN arrest at 1, 3, and 5 years, respectively. The major complication rate was 1.9%. Mean (SD) length of stay was 2.7 (0.0-7.0) days. Mean (SD) radiographic follow-up was 29.3 (30.7) months.

Conclusions and Relevance

The findings of this large retrospective patient case series support the continued success of the ALTFL rescue flap technique, a safe and highly effective long-term treatment for mandibular ORN in carefully selected patients.

Immune microenvironment: novel perspectives on bone regeneration disorder in osteoradionecrosis of the jaws

Osteoradionecrosis of the jaws (ORNJ) is a severe complication that occurs after radiotherapy of head and neck malignancies. Clinically, conservative treatments and surgeries for ORNJ exhibited certain therapeutic effects, whereas the regenerative disorder of the post-radiation jaw remains a pending problem to be solved. In recent years, the recognition of the role of the immune microenvironment has led to a shift from an osteoblasts (OBs) or bone marrow mesenchymal stromal cells (BMSCs)-centered view of bone regeneration to the concept of a complicated microecosystem that supports bone regeneration. Current advances in osteoimmunology have uncovered novel targets within the immune microenvironment to help improve various regeneration therapies, notably therapies potentiating the interaction between BMSCs and immune cells. However, these researches lack a thorough understanding of the immune microenvironment and the interaction network of immune cells in the course of bone regeneration, especially for the post-operative defect of ORNJ. This review summarized the composition of the immune microenvironment during bone regeneration, how the immune microenvironment interacts with the skeletal system, and discussed existing and potential strategies aimed at targeting cellular and molecular immune microenvironment components.