Efficacy of pentoxifylline–tocopherol–clodronate in mandibular osteoradionecrosis

Is the use of Pentoxifylline and Tocopherol effective in the treatment of Osteoradionecrosis of the jaws or for the treatment of medicationosteonecrosis of the jaw? An overview

PURPOSE

The aim of the present study was to determine the methodological quality of systematic reviews that evaluated the effectiveness of pentoxifylline and tocopherol (PENTO) in the treatment of osteoradionecrosis of the jaw (ORNJ) and medication-related osteonecrosis of the jaw (MRONJ).

METHODS

Searches were performed in Databases including PubMed, Scopus, LILACS, DARE, Cochrane Library, and SIGLE through OpenGrey until March 2024, were evaluated by two independent reviewers to answer the following question: Is the use of PENTO protocol effective in the treatment of ORNJ or for the treatment of MRONJ?

RESULTS

A total of 256 articles were initially identified; however, following the use of appropriate inclusion and exclusion criteria, five systematic reviews were identified for detailed analysis. The final study sample comprised 588 patients: 397 patients with ORN and 197 patients with MRONJ who were treated with PENTO. The total recovery of individuals who used the PENTO protocol was 62,2 % for ORN and 100 % for MRONJ, with a follow-up period of 1 month to 10 years. The methodological quality of the studies was assessed using the AMSTAR 2 tool, in which four were of low quality and 1 moderate quality.

CONCLUSION

The treatment of ORN and MRONJ with pentoxifylline and tocopherol has shown good results in the studies presented, with a partial or total reduction in bone exposure. However, the low quality of the relevant reports highlights the need for primary and secondary studies with better methodological rigor to reduce bias and provide reassurance for this treatment option.

Effect of Statins on Patients With Osteoradionecrosis of the Jaw

BACKGROUND

Osteoradionecrosis of the jaw (ORN) is a late complication of radiation therapy. Radiation-induced fibrosis is the most likely mechanism for developing ORN, and statins are effective against radiation-induced fibrosis. However, no reports have indicated the direct effectiveness of statins in treating ORN.

PURPOSE

This study aimed to measure the association between statin exposure and ORN disease resolution.

STUDY DESIGN, SETTING, SAMPLE

This retrospective cohort study included patients with ORN diagnosed between January 2008 and December 2020 at the Hospital's Department of Oral and Maxillofacial Surgery. Patients who were immunocompromised or followed up for < 6 months were excluded.

PREDICTOR VARIABLE

The predictor variable was statin exposure, which was defined as the use of statins for dyslipidemia.

MAIN OUTCOME VARIABLE

The main outcome variable was ORN disease progression status (good prognosis). Patients who showed full recovery and improvement were included in the good prognosis group, and those who showed invariance and deterioration were included in the poor prognosis group.

COVARIATES

We analyzed the clinicodemographic including the age of onset, sex, history of smoking, alcohol consumption, history of chemotherapy, tumor site, association with dental treatment, location (maxilla or mandible), the time to ORN onset from radiation therapy, and stage of ORN, and treatment characteristics including hyperbaric oxygen therapy, long-term macrolide administration, and sequestrectomy.

ANALYSES

We analyzed the association between statin exposure or covariates and time to ORN improvement using bivariate and multivariate Cox regression. The significance level was set at P = .05.

RESULTS

We analyzed 102 patients, and the improvement rate was 32.4%. The favorable prognostic factors were statin exposure (adjusted hazard ratio [HR], 3.71; 95% confidence interval [CI], 1.62 to 8.50; P = .002), onset in the maxilla (HR, 2.15; 95% CI, 1.02 to 4.55; P = .045), and stage 1 of ORN (HR, 2.65; 95% CI, 1.20 to 5.83; P = .016).

CONCLUSION AND RELEVANCE

In this study, statin exposure, onset in the maxilla, and stage 1 of Lyons's classification were favorable prognostic factors for ORN. Although this study's findings were insufficient to recommend statin use for ORN, statins may be a novel and effective treatment for ORN.

Microvascular reconstruction of medication related osteonecrosis of the head and neck

BACKGROUND

Medication related osteonecrosis of the jaw (MRONJ) requiring free flap (FF) reconstruction is uncommon with limited reported findings.

METHODS

Multicenter, retrospective case series of 49 consecutive adult patients presenting with advanced MRONJ requiring FF reconstruction from 2010 to 2022. Perioperative complications and outcomes were analyzed.

RESULTS

Eighty-two percent (n = 40) of cases were of the mandible and 18% (n = 9) were of the maxilla. The mean follow-up was 15 months (±19.6). The majority of FF survived (96%, n = 47). FF reconstructions of the maxilla were more likely to require postoperative debridement (56%, 95% CI [27, 81%] vs. 15%, 95% CI [7, 25%], p = 0.008) or develop intraoral bone exposure (56%, 95% CI [27, 81%] vs. 18%, 95% CI [9, 27%], p = 0.02). Most patients (71%, n = 35) received preoperative antibiotics which was associated with a higher rate of FF survival (100% vs. 86%, 95% CI [60, 96%], p = 0.02) and fewer complications.

CONCLUSIONS

Patients undergoing FF reconstruction for MRONJ do well with high rates of FF success. MRONJ of the maxilla have a higher rate of some complications. Preoperative antibiotics correlated with higher FF survival and fewer postoperative complications.

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.

Mandibular Osteoradionecrosis: Defining the Microbial Milieu and Antimicrobial Resistance at the Time of Rescue Flap Surgery

OBJECTIVE

To report the microorganisms and their antibiotic sensitivity profile from tissue cultures and stains at the time of anterolateral thigh fascia lata (ALTFL) rescue flap for management of mandibular osteoradionecrosis (ORN).

METHODS

Retrospective chart review of patients who underwent ALTFL rescue flap for native mandibular ORN between 2011 and 2022.

RESULTS

Twenty-six cases comprising 24 patients (mean age 65.4 years, 65.4% male) with mandibular ORN from whom tissue cultures and gram stain were obtained at the time of ALTFL rescue flap. 57.7% grew bacterial species, while 34.6% grew fungal species. Multibacterial speciation was noted in 26.9% of cultures. A combination of bacterial and fungal growth was also seen in 15.4% of cases. All gram-positive cocci (GPC) were pansensitive to antibiotics except for one case of Staphylococcus aureus, which was resistant to levofloxacin. Gram-negative bacilli (GNB) species were isolated in 50.0% of cases. All fungal growth was due to Candida species. No growth was noted in 23.1% of cases. Multidrug resistance was noted in 53.8% of cases when GNB was isolated.

CONCLUSION

We report 76.9% of our cases of mandibular ORN had microbial growth from tissue cultures obtained at the time of the ALTFL rescue flap. Fungal growth was noted in a substantial number of cases and should be obtained as a specimen when pursuing culture-driven antibiotic therapy. Most GPCs were pansensitive to antibiotics, while GNBs were often the harbinger of multidrug resistant mandibular ORN.

LEVEL OF EVIDENCE

4 Laryngoscope, 134:166-169, 2024.

ATG7-mediated autophagy protects human gingival myofibroblasts from irradiation-induced apoptosis

BACKGROUND

Apoptosis resistance of myofibroblasts is critical in pathology of irradiation-induced fibrosis and osteoradionecrosis of the jaw (ORNJ). However, molecular mechanism of apoptosis resistance induced by irradiation in oral myofibroblasts remains largely obscure.

METHODS

Matched ORNJ fibroblasts and normal fibroblasts pairs from gingival were primarily cultured, and myofibroblast markers of α-SMA and FAP were evaluated by qRT-PCR and western blot. CCK8 assay and flow cytometric analysis were performed to investigate the cell viability and apoptosis under irradiation treatment. Autophagy-related protein LC3 and ATG7, and punctate distribution of LC3 localization were further detected. After inhibition of autophagy with inhibitor CQ and 3-MA, as well as transfected ATG7-siRNA, cell viability and apoptosis of ORNJ and normal fibroblasts were further assessed.

RESULTS

Compared with normal fibroblasts, ORNJ fibroblasts exhibited significantly higher α-SMA and FAP expression, increased cell, viability and decreased apoptosis under irradiation treatment. LC3-II and ATG7 were up-regulated in ORNJ fibroblasts with irradiation stimulation. After inhibition of irradiation-induced autophagic flux with lysosome inhibitor CQ, LC3-II protein was accumulated and punctate distribution of LC3 localization was increased in ORNJ fibroblasts. Moreover, autophagy inhibitor CQ and 3-MA enhanced the irradiation-induced apoptosis but inhibited viability of ORNJ fibroblasts. Silencing ATG7 with siRNA could obviously weaken irradiation-induced LC3-II expression, and promoted irradiation-induced apoptosis of ORNJ fibroblasts. After knockdown of ATG7, finally, p-AKT(Ser473) and p-mTOR(Ser2448) levels of ORNJ fibroblasts were significantly increased under irradiation.

CONCLUSION

Compared with normal fibroblasts, human gingival myofibroblasts are resistant to irradiation-induced apoptosis via autophagy activation. Silencing ATG7 may evidently inhibit activation of autophagy, and promote apoptosis of gingival myofibroblasts via Akt/mTOR pathway.

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.

Pentoxifylline and tocopherol for prevention of osteoradionecrosis in patients who underwent oral surgery: A clinical audit

PURPOSE

Osteoradionecrosis (ORN) of the jaw is a severe and debilitating complication of the head and neck radiotherapy which frequently occurrs after oral surgery. This clinical audit aims aevaluate the effectiveness of combined use of pentoxifylline and tocopherol (PENTO) in prevention ORN onset in patient who underwent oral surgery after head and neck radiotherapy (RT).

MATERIAL METHOD

In this clinical audit Pentoxifylline 400 mg, twice a day, and Tocopherol 800 IU once a day (PENTO protocol) have been prescribed. Patients started the protocol 1 week before the surgical procedure and continued for 8 weeks after.

RESULTS

Twenty-nine patients were included. They received 75 surgical interventions under PENTO protocol: 71 surgical procedures of dental extraction (single or multiple dental extractions in each session) and four implant placements. A total of 152 dental extractions were carried out: 64 surgical extractions which required the raising of mucoperiosteal flap, and 88 simple extractions. Four out of 29 patients developed ORN after surgical procedures: four cases of ORN occurred after dental extractions (5.6%) and one case of ORN after implant placement (25%).

CONCLUSION

PENTO is a useful ORN preventive protocol, low-cost and clinically feasible, safe and well tolerated by patients. Further studies should focus on better defining the effectiveness PENTO, independently from the antibiotic therapy.

Free Tissue Transfer for Skull Base Osteoradionecrosis: A Novel Approach in the Endoscopic Era

OBJECTIVES

Osteoradionecrosis (ORN) of the skull base and craniovertebral junction is a challenging complication of radiation therapy (RT). Severe cases often require surgical intervention through a multi-modal approach. With the evolution in endoscopic surgery and advances in skull base reconstruction, there is an increasing role for microvascular free tissue transfer (MFTT). We describe an endoscopic-assisted approach for the management of ORN of the skull base using fascia lata for MFTT.

STUDY DESIGN

Retrospective case series.

METHODS

Between 2017 and 2021, a review of all cases in which fascia lata MFTT was utilized for skull base ORN was performed. Patient demographics, preoperative characteristics, and postoperative outcomes with long-term follow-up were reviewed.

RESULTS

Five patients were identified. Mean duration to onset of ORN was 17 months following RT. A trial of antibiotics, hyperbaric oxygen (HBO), and/or limited debridement was attempted without success. Refractory pain and progressive osteomyelitis were unifying symptoms. All patients underwent endoscopic debridement of the affected region of ORN prior to MFTT. Vascularized fascia lata was inset through a combined endonasal and transoral corridor. There was improvement in chronic pain in the postop setting with no patients requiring continued antibiotics or HBO therapy. Mean post-op follow-up was 23 months.

CONCLUSIONS

With continued evolution in endoscopic, minimally invasive approaches, there is an expanding indication for early surgical management in refractory ORN. Fascia lata MFTT is a novel and effective strategy for the management of ORN of the skull base and upper cervical spine with excellent postoperative outcomes and limited patient morbidity.

LEVEL OF EVIDENCE

4 Laryngoscope, 133:562-568, 2023.

Protective effects of pentoxifylline against chlorine-induced acute lung injury in rats

OBJECTIVE

Chlorine is a chemical threat agent that can be harmful to humans. Inhalation of high levels of chlorine can lead to acute lung injury (ALI). Currently, there is no satisfactory treatment, and effective antidote is urgently needed. Pentoxifylline (PTX), a methylxanthine derivative and nonspecific phosphodiesterase inhibitor, is widely used for the treatment of vascular disorders. The present study was aimed to investigate the inhibitory effects of PTX on chlorine-induced ALI in rats.

METHODS

Adult male Sprague-Dawley rats were exposed to 400 ppm Cl₂ for 5 min. The histopathological examination was carried out and intracellular reactive oxygen species (ROS) levels were measured by the confocal laser scanning system. Subsequently, to evaluate the effect of PTX, a dose of 100 mg/kg was administered. The activities of superoxide dismutase (SOD) and the contents of malondialdehyde (MDA), glutathione (GSH), oxidized glutathione (GSSG) and lactate dehydrogenase (LDH) were determined by using commercial kits according to the manufacturer's instructions. Western blot assay was used to detect the protein expressions of SOD1, SOD2, catalase (CAT), hypoxia-inducible factor (HIF)-1α, vascular endothelial growth factor (VEGF), occludin, E-cadherin, bcl-xl, LC 3, Beclin 1, PTEN-induced putative kinase 1 (PINK 1) and Parkin.

RESULTS

The histopathological examination demonstrated that chlorine could destroy the lung structure with hemorrhage, alveolar collapse, and inflammatory infiltration. ROS accumulation was significantly higher in the lungs of rats suffering from inhaling chlorine (P<0.05). PTX markedly reduced concentrations of MAD and GSSG, while increased GSH (P<0.05). The protein expression levels of SOD1 and CAT also decreased (P<0.05). Furthermore, the activity of LDH in rats treated with PTX was significantly decreased compared to those of non-treated group (P<0.05). Additionally, the results also showed that PTX exerted an inhibition effect on protein expressions of HIF-1α, VEGF and occludin, and increased the level of E-cadherin (P<0.05). While the up-regulation of Beclin 1, LC 3II/I, Bcl-xl, and Parkin both in the lung tissues and mitochondria, were found in PTX treated rats (P<0.05). The other protein levels were decreased when treated with PTX (P<0.05).

CONCLUSION

PTX could ameliorate chlorine-induced lung injury via inhibition effects on oxidative stress, hypoxia and autophagy, thus suggesting that PTX could serve as a potential therapeutic approach for ALI.

Carbon Dioxide Laser Sequestrectomy for Osteoradionecrosis: A Case Series

Objective: To demonstrate a new approach to sequestrectomy using a carbon dioxide (CO₂) laser for a clinic-based technique. Background: Osteoradionecrosis (ORN) of the jaw is a debilitating complication of radiotherapy for head and neck malignancies. Often refractory to medical therapy, surgical intervention for early staged disease with curettage and mechanical bone removal has mixed success, making this disease extremely difficult to treat. Therefore, new approaches to treat ORN of the jaw is needed. Methods: We describe five cases of early-to-intermediate-staged ORN illustrating a novel clinic-based sequestrectomy technique using a CO₂ laser. Results: The exposed bone lesions involved the mandibular fixed gingiva, maxillary fixed gingiva, and hard palate. None of the patients had diabetes. Four patients required a total of two laser treatments and one patient needed only one treatment. All five patients demonstrated an excellent response with complete resolution of their ORN-related pain and complete mucosal coverage of the exposed bone with durable results (follow-up range, 7-19 months). Conclusions: This small series demonstrates encouraging results for CO₂ laser sequestrectomy for ORN. This novel office-based intervention merits further study in larger prospective series and exploration in other disease populations, such as medication-related osteonecrosis of the jaws.

Patients' experience and perceived concerns regarding obtaining and taking prescriptions for head and neck osteoradionecrosis

The main components of the medical management of osteoradionecrosis (ORN) are combinations of clodronate, pentoxifylline, tocopherol, sometimes with antibiotics or chlorhexidine rinses. Anecdotally in the Cheshire and Merseyside network, patients report having difficulties getting and taking their prescription, hence the aim was to survey patient experience of obtaining prescriptions, administration of the medications, and side effects. Patients prescribed tocopherol and pentoxifylline from the pharmacy department's record database from the period of January 2019 to June 2020 were invited to take part in a semi-structured telephone survey. Sixteen patients out of a total 33 (48%) responded. 11 patients (69%) reported some issue collecting their repeat prescriptions, commonly low stock of medicines in community or unwillingness of GPs to prescribe. One patient permanently stopped treatment owing to difficulties obtaining medication, whilst for three there were temporary gaps in treatment. Difficulty in administration of the medications was reported in 7 patients (44%) patients, most commonly in those with pre-existing dysphagia. Issues related to difficulties in swallowing the large pentoxifylline tablet or with the vitamin E capsules. Patients crushed the medications, but this was associated with gastrointestinal side-effects in one patient who had to stop treatment. One patient stopped chlorhexidine mouthwash due to oral soreness. In conclusion, medical management of ORN is well tolerated by patients. There is difficulty for patients getting prescriptions in primary care. Few patients need to stop taking the medication due to difficulty in administration or side-effects. More patient information would be useful for all concerned.

Treatment of Soft-Tissue Necrosis of the Pyriform Sinus Using Pentoxyllifylline and Tocopherol

Radiotherapy of the head and neck can often lead to complications and side effects, including osteoradionecrosis and soft tissue necrosis. One relatively well-established method of treating osteoradionecrosis includes the PENTOCLO protocol, which consists of Pentoxyllifylline, Tocopherol, and Clodronate. Despite its success in the treatment of osteoradionecrosis, the effectiveness of components of the PENTOCLO protocol in treating soft tissue necrosis of the head and neck is underexplored. This case study reviews the successful treatment of a pyriform sinus ulcer that developed after the use of radiotherapy in treating a T3N2b squamous cell carcinoma. The treatment plan used Pentoxyllifylline and Tocopherol, and omitted Clodronate, and can therefore be referred to as a PENTO protocol.

Osteoradionecrosis: Exposing the Evidence Not the Bone

Osteoradionecrosis is a relatively rare but potentially morbid and costly complication of radiation therapy for head and neck cancer. Multidisciplinary diagnosis and treatment are essential. Despite evidence guiding individual aspects of care for osteoradionecrosis, there is a lack of broad consensus on the overall diagnosis and management of this condition. This study comprehensively reviews the literature, with a focus on the past 10 years, to guide evaluation and treatment.

Timing of dental extractions in patients undergoing radiotherapy and the incidence of osteoradionecrosis: a systematic review and meta-analysis

This systematic review aimed to examine whether the incidence of osteonecrosis differed between patients who have dental extractions before or after radiotherapy (RT). The reported incidence of osteoradionecrosis (ORN) of the jaws following RT to the head and neck varies widely in the literature. Currently, for patients with head and neck cancer there are no universally accepted guidelines on the optimal timing of dental surgery relative to RT to minimise incident ORN. A literature review was conducted using the Preferred Reporting Items for Systematic Review and Meta-Analysis (PRISMA) criteria. A search of PubMed, EMBASE, Evidence-Based Medicine, and Web of Science databases targeted literature published up to and including 10 April 2020. Two independent reviewers assessed studies for eligibility against inclusion criteria. An assessment of bias was conducted for each of the included studies and relevant data extracted. A meta-analysis was undertaken using the statistical methods described. Twenty-four of 708 studies were included. They were heterogeneous and included a wide variation of RT methods, head and neck malignancies, and comorbidities. While some concluded that the incidence of ORN was dependent on the timing of dental extractions in relation to RT, with regard to the risk of its development, others reported additional factors such as age, comorbidities, extent of surgical resection, and dose and field of radiation, as more important predictors than timing. In many there was consistent lack of detail around the timing of dental procedures in relation to the delivery of RT. From 21 studies including 36,294 patients, of whom 14,389 had extractions before RT, the pooled incidence of ORN was 5.5% (95% CI: 2.1% to 10.1%). Significant heterogeneity was found in Cochran's Q-test (p<0.001) and Higgins I²=98.0%. From 21 studies including 37,805 patients, of whom 6030 had extractions after RT, the pooled incidence of ORN was 5.3% (95% CI: 2.9% to 8.2%). Significant heterogeneity was found in Cochran's Q-test (p<0.001) and Higgins I²=80.0%. There was no statistically significant difference between these two groups (random-effects model Q=0.12, p=0.73). Large, longitudinal studies with a priori-specified methods are needed to identify, recruit, and prospectively follow patients with head and neck cancer for the onset of ORN after dental surgery. This will allow clinical guidelines to be established to assist clinicians to plan treatment when extractions are indicated in patients undergoing RT to the head and neck.