Bisphosphonate-related osteonecrosis of the jaw in metastatic breast cancer patients: a review of 25 cases

Mechanism of bisphosphonate-related osteonecrosis of the jaw (BRONJ) revealed by targeted removal of legacy bisphosphonate from jawbone using competing inert hydroxymethylene diphosphonate

Bisphosphonate-related osteonecrosis of the jaw (BRONJ) presents as a morbid jawbone lesion in patients exposed to a nitrogen-containing bisphosphonate (N-BP). Although it is rare, BRONJ has caused apprehension among patients and healthcare providers and decreased acceptance of this antiresorptive drug class to treat osteoporosis and metastatic osteolysis. We report here a novel method to elucidate the pathological mechanism of BRONJ by the selective removal of legacy N-BP from the jawbone using an intra-oral application of hydroxymethylene diphosphonate (HMDP) formulated in liposome-based deformable nanoscale vesicles (DNV). After maxillary tooth extraction, zoledronate-treated mice developed delayed gingival wound closure, delayed tooth extraction socket healing and increased jawbone osteonecrosis consistent with human BRONJ lesions. Single cell RNA sequencing of mouse gingival cells revealed oral barrier immune dysregulation and unresolved proinflammatory reaction. HMDP-DNV topical applications to nascent mouse BRONJ lesions resulted in accelerated gingival wound closure and bone socket healing as well as attenuation of osteonecrosis development. The gingival single cell RNA sequencing demonstrated resolution of chronic inflammation by increased anti-inflammatory signature gene expression of lymphocytes and myeloid-derived suppressor cells. This study suggests that BRONJ pathology is related to N-BP levels in jawbones and demonstrates the potential of HMDP-DNV as an effective BRONJ therapy.

Clinical profile of individuals with bisphosphonate-related osteonecrosis of the jaw: an integrative review

BACKGROUND

Bisphosphonate-related osteonecrosis of the jaw (BRONJ) is still the most prevalent type of osteonecrosis with clinical relevance. In Brazil, bisphosphonate use is high but there is a lack of epidemiological studies on BRONJ.

OBJECTIVE

To determine the clinical profile of BRONJ in a Brazilian population through an integrative review.

DESIGN AND SETTING

Integrative review of BRONJ in a Brazilian population.

METHODS

Cases and clinical research on Brazilians with BRONJ between 2010 and 2019, indexed in PubMed/MEDLINE, Scopus, Web of Science and LILACS were reviewed. Age, sex, type and time of bisphosphonate intake, administration route, related diseases, region of the BRONJ, diagnostic criteria, staging, triggering factor and type of treatment were analyzed.

RESULTS

Fifteen articles on 128 subjects were included. Most patients were women (82.03%); the mean age was 63 years. Intravenous zoledronic acid was mostly used (62.50%), for breast cancer treatment (46.87%). The main localization of BRONJ was the mandible (54.68%), associated mainly with tooth extractions (45.98%). The diagnostic criteria were clinical (100%) and radiographic (89.06%), mostly in stage II (68.08%). The surgical treatments were sequestrectomy (37.50%) and platelet-rich plasma (PRP) (36.71%). Microbial control was done using chlorhexidine (93.75%) and infection control using clindamycin (53.90%).

CONCLUSIONS

BRONJ had higher prevalence in Brazilian women receiving treatment for breast cancer and osteoporosis. The mandible was the region most affected with a moderate stage of BRONJ, particularly when there were histories of tooth extraction and peri-implant surgery. Sequestrectomy with additional drugs and surgical therapy was the treatment most accomplished.

Overall and disease-specific survival outcomes following primary surgery for oral squamous cell carcinoma: analysis of consecutive 67 patients

Objectives

This study evaluated the predictive factors for survival of patients with oral squamous cell carcinoma (OSCC) and investigated the overall and disease-specific survival (DSS) outcomes.

Materials and Methods

A total of 67 consecutive patients who underwent surgery for OSCC from January 2006 to November 2014 were included in this study. Patients were classified according to age, sex, pTNM stages, primary sites, smoking and alcohol drinking habits, depth of invasion, perineural and lymphovascular invasion, cell differentiation and postoperative radiotherapy. Kaplan-Meier methods were used to estimate the survival categorized by patient groups. Cox regression methods were used to investigate the main independent predictors of survival.

Results

Nineteen patients died of OSCC during follow-up periods. Another five patients died of other diseases including lung adenocarcinoma (n=1), cerebral infarction (n=1), general weakness (n=2), and pneumonia (n=1). The tongue (n=16) was the most common site for primary origin, followed by buccal mucosa (n=15), mandibular gingiva (n=15), maxillary gingiva (n=9), floor of mouth (n=9), retromolar trigone (n=2), and palate (n=1). Eleven patients had pTNM stage I disease, followed by stage II (n=22) and stage IV (n=34). No patients had pTNM stage III disease in this study. The overall survival of all patients was 64.2% and the DSS was 71.6%. DSS of patients with stage I and II disease was 100%. Stepwise Cox regression showed the two predictors for DSS were pTNM stage (P<0.0001, odds ratio=19.633) and presence of metastatic lymph nodes (P=0.0004, odds ratio=0.1039).

Conclusion

OSCC has been associated with poor prognosis; however, there were improved survival outcomes compared with past studies. Advanced-stage disease and presence of metastatic lymph nodes were associated with poorer survival compared with early-stage OSCC and absence of neck node metastasis. Stage I and II OSCC were associated with excellent survival results in this study.

Mindfulness-Based Stress Reduction on breast cancer symptoms: systematic review and meta-analysis

Mindfulness-Based Stress Reduction practices increase the capacity for concentration and attention, and these practices are particularly effective for people with breast cancer. To analyze the effects of the application of Mindfulness-Based Stress Reduction on breast cancer symptoms. Systematic review and meta-analysis were carried out. To find suitable studies, the PubMed/ MEDLINE database was searched using the keywords "breast cancer" and "Mindfulness-Based Stress Reduction". Studies included were published between 2013 and 2017, written in English and showed methodological quality through the PEDro scale (score greater than 3). They also presented empirical evidence, had an experimental study design (randomized or non-randomized), and had full text available. For the meta-analysis, we used a random-effects model, with standardized mean differences and 95% confidence intervals. Seven studies were included, one non-randomized and containing only an intervention group of Mindfulness-Based Stress Reduction, and six randomized including samples of two or three groups. The non-randomized study showed 6 points on the PEDro scale, the randomized studies of two groups 6 to 7 points and studies with three groups showed 7 points. In the meta-analysis of the two randomized studies, the results, although not significant, revealed a moderate effect for Mindfulness-Based Stress Reduction on the outcome of fatigue, with a mean difference of -0.42 (95%CI -0.92- -0.07; p=0.09). Mindfulness-Based Stress Reduction seems to be a promising alternative for treatment of this disease's symptoms.

Machine learning to predict the occurrence of bisphosphonate-related osteonecrosis of the jaw associated with dental extraction: A preliminary report

INTRODUCTION

The aim of this study was to build and validate five types of machine learning models that can predict the occurrence of BRONJ associated with dental extraction in patients taking bisphosphonates for the management of osteoporosis.

PATIENTS & METHODS

A retrospective review of the medical records was conducted to obtain cases and controls for the study. Total 125 patients consisting of 41 cases and 84 controls were selected for the study. Five machine learning prediction algorithms including multivariable logistic regression model, decision tree, support vector machine, artificial neural network, and random forest were implemented. The outputs of these models were compared with each other and also with conventional methods, such as serum CTX level. Area under the receiver operating characteristic (ROC) curve (AUC) was used to compare the results.

RESULTS

The performance of machine learning models was significantly superior to conventional statistical methods and single predictors. The random forest model yielded the best performance (AUC = 0.973), followed by artificial neural network (AUC = 0.915), support vector machine (AUC = 0.882), logistic regression (AUC = 0.844), decision tree (AUC = 0.821), drug holiday alone (AUC = 0.810), and CTX level alone (AUC = 0.630).

CONCLUSIONS

Machine learning methods showed superior performance in predicting BRONJ associated with dental extraction compared to conventional statistical methods using drug holiday and serum CTX level. Machine learning can thus be applied in a wide range of clinical studies.

Clinical characteristics and recurrence-related factors of medication-related osteonecrosis of the jaw

OBJECTIVES

The purpose of this study was to investigate the demographic and clinical characteristics of patients with medication-related osteonecrosis of the jaw (MRONJ) and to elucidate factors affecting recurrence in surgical treatment.

MATERIALS AND METHODS

A total of 51 patients who were diagnosed with MRONJ were analyzed according to demographic and clinical features and treatment results through a retrospective chart review from 2013 to 2017 in the Department of Oral and Maxillofacial Surgery, Korea University Anam Hospital, Seoul in Korea.

RESULTS

Alendronate composed the majority of medication doses (55.6%), followed by ibandronate (20.0%), risedronate (15.6%), and zoledronate (6.7%). Forty patients (88.9%) were given oral medication, and five patients (11.1%) were intravenously treated, and the mean duration of medication use was 61.1±42.9 months. A total of 10 patients (22.2%) had a drug holiday before MRONJ-induced dental treatment lasting an average of 6.8±7.0 months. MRONJ occurred 2.7 times more in the mandible, with 41 cases (73.2%) occurring in the mandible and 15 cases (26.8%) occurring in the maxilla, and the prevalence of affected posterior parts (premolar-molar) was six times greater than that of the anterior parts (incisor-canine) (48 cases vs 8 cases, 85.7% vs 14.3%). The most common dental cause of MRONJ was tooth extraction (69.6%). Regarding recurrence, there was no statistical difference in recurrence rate according to either site or stage. However, recurrence occurred in 4 out of 34 cases (11.8%) in the primary closure group and 9 out of 20 cases (45.0%) in the secondary healing group, and there was a statistical difference with respect to closure technique.

CONCLUSION

The identified risk factors in patients taking bone resorption inhibitors can aid dental clinicians in ensuring prevention and proper treatment of MRONJ.

Uncommon presentation of potential medication-related osteonecrosis of the jaw

Background

This article presents a patient with potential atypical medication-related osteonecrosis of the jaw and reviews related literatures.

Case presentation

A 52-year-old male showed pain in the left buccal area and had numbness on the left lower lip area. He received medications having anti-angiogenic effect for 4 years. He did not receive irradiation of the jaw regions. In histological view, most of the adipocytes were destroyed and disappeared in the scanty vascular marrow tissue, resulting in the replacement of the fatty necrosis with variable sized vacuolated empty spaces. In the immunohistochemistry analysis, the infiltrated macrophages into the marrow stromal tissue were strongly positive for lysozymes. These findings demonstrate that the presented osteonecrosis underwent a chronic and persistent granulomatous inflammatory reaction.

Conclusions

We conclude that the present case might have been caused by anti-angiogenic drug abuse, affecting the reduction of the mandibular marrow vascularity and subsequently inducing fatty necrosis and an extensive osteolytic change of the mandible.