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This is a unique case report of a 67-year-old female diagnosed with multiple myeloma and extensive use of intravenous bisphosphonate, whose clinical and radiographic presentation of an oral lesion made it challenging to confirm its definitive diagnosis. This patient was referred to the dental service for a suspected medication-related osteonecrosis of the jaw (MRONJ). Clinically, the lesion was located underneath a fixed partial denture in the left posterior mandible. There was a purulent swelling on the lingual side of the fixed partial denture, and a hyperplastic exophytic lesion on the buccal side of the bridge. Panoramic radiograph showed a well circumscribed radiolucent lesion in the left mandible. A biopsy of the gingival lesion on the buccal aspect was inconclusive. As the positron emission tomography scan showed lytic lesions, oral manifestation of multiple myeloma could not be ruled out. A computed tomography-guided biopsy of the left mandible showed plasma cell neoplasm in the histological analysis. Upon confirmed diagnosis, the patient was treated with 20Gy to the left mandible and subsequent debridement of the loose necrotic bone. Following treatment, this gingival lesion resolved completely, and the tumour has remained stable till date.

Intraoral radiation stents (IRS) are prosthetic devices that assist in the effective delivery of radiation to tumor tissues and aim to avoid unnecessary radiation to adjacent healthy tissues, thus limiting postradiotherapy toxicities. They are used to protect or displace vital structures, assist in positioning of the treatment beam for effective administration of radiotherapy, carry a radioactive material, shield healthy tissues of the oral cavity, and/or maintain the desired mouth opening during radiotherapy. With close collaboration between radiation oncologist and oral health care provider, several IRS can be fabricated by the latter for appropriate targeting and delivery of planned radiation dose and optimized treatment results. Modification of these IRS based on individual patient need is recommended to maximize prosthesis utility. The purpose of this review is to discuss the various types of IRS and highlight their clinical utility and benefits in patients receiving radiation therapy in the head and neck cancers.

Background A case-control study was performed to define clinical and genetic risk factors associated with osteonecrosis of the jaw in patients with metastatic cancer treated with bisphosphonates. Methods Clinical data and tissues were collected from patients treated with bisphosphonates for metastatic bone disease who were diagnosed with osteonecrosis of the jaw (cases) and matched controls. Clinical data included patient, behavioral, disease, and treatment information. Genetic polymorphisms in CYP2C8 (rs1934951) and other candidate genes were genotyped. Odds ratios from conditional logistic regression models were examined to identify clinical and genetic characteristics associated with case or control status. Results The study population consisted of 76 cases and 126 controls. In the final multivariable clinical model, patients with osteonecrosis of the jaw were less likely to have received pamidronate than zoledronic acid (odds ratio = 0.18, 95% Confidence interval: 0.03-0.97, p = .047) and more likely to have been exposed to bevacizumab (OR = 5.15, 95% CI: 1.67-15.95, p = .005). The exploratory genetic analyses suggested a protective effect for VEGFC rs2333496 and risk effects for VEGFC rs7664413 and PPARG rs1152003. Conclusions We observed patients with ONJ were more likely to have been exposed to bevacizumab and zoledronic and identified potential genetic predictors that require validation prior to clinical translation.

Background Radiotherapy (RT), the main treatment for patients with head and neck cancer, can lead to dental complications. Methods We identified 244 patients with squamous cell carcinoma of the tonsil treated with RT from 2004 to 2013. For each patient, we contoured the 10 tooth-bearing regions and calculated the radiation dose (gray, Gy) to each region. From this data set, we built two predictive models to determine the expected maximum radiation dose, one for the non-molar regions and another for the molar regions. Results For the non-molars, the final model included location, T-classification, and overall stage, with a median absolute prediction error of 7.0 Gy. For the molars, the final model included location, T-classification, overall stage, and treatment year, with a median absolute error of 6.0 Gy. Conclusions Our current model offers a good estimation of the maximum radiation dose delivered to different regions of the jaw; future work will independently validate these models.

Background Although metastatic involvement of bony sites including cranial bones is common in neuroblastoma (NB), mandibular metastases (MM) are uncommon, and specific outcomes have not been reported upon in the modern therapeutic era. Methods In this retrospective study, medical records on patients with MM from NB were reviewed. Statistical analysis was performed using the Kaplan-Meier method. Results Of 29 patients, nine (31%) had MM at diagnosis, whereas in 20 (69%) MM were first detected at NB relapse at a median time of 26 (6-89) months from diagnosis. Median maximal diameter of lesions was 3 (range 0.8-4.9) cm. MM were unilateral in 83% of patients, with ascending ramus (55%) and mandibular body (38%) being the two most common sites. All patients received systemic chemotherapy, and 26 (93%) patients received radiotherapy to MM. At a median follow-up of 37.3 (24.2-219.5) months, eight of nine patients with MM at diagnosis did not experience mandibular progressive disease. Eighteen of 20 patients with MM at relapse received therapeutic radiotherapy; objective responses were noted in 78%. Seventy-two percent (5/18) had not experienced relapse within the radiation field at a median of 12 (2-276) months postradiotherapy. Dental findings at follow-up after completion of NB therapy included hypodontia, hypocalcification of enamel, and trismus. Median 3-year overall survival in patients with relapsed MM was 51 ± 12% months from relapse. Conclusion MM when detected at diagnosis is associated with a prognosis similar to that for other skeletal metastases of NB. Radiotherapy is effective for control of MM detected both at diagnosis and relapse. Significant dental abnormalities posttherapy warrant regular dental evaluations and appropriate intervention.

Oral Diseases (2012) 18, 602–612 Objective: Infection has been hypothesized as a contributing factor to bisphosphonate (BP)-related osteonecrosis of the jaw (BRONJ). The objective of this study was to determine the bacterial colonization of jawbone and identify the bacterial phylotypes associated with BRONJ. Materials and methods: Culture-independent 16S rRNA gene-based molecular techniques were used to determine and compare the total bacterial diversity in bone samples collected from 12 patients with cancer (six, BRONJ with history of BP; six, controls without BRONJ, no history of BP but have infection). Results: Denaturing gradient gel electrophoresis profile and Dice coefficient displayed a statistically significant clustering of profiles, indicating different bacterial population in BRONJ subjects and control. The top three genera ranked among the BRONJ group were Streptococcus (29%), Eubacterium (9%), and Pseudoramibacter (8%), while in the control group were Parvimonas (17%), Streptococcus (15%), and Fusobacterium (15%). H&E sections of BRONJ bone revealed layers of bacteria along the surfaces and often are packed into the scalloped edges of the bone. Conclusion: This study using limited sample size indicated that the jawbone associated with BRONJ was heavily colonized by specific oral bacteria and there were apparent differences between the microbiota of BRONJ and controls.

Purpose: The aim of this study was to investigate the usefulness of the QUANTEC guideline to prevent xerostomia after intensity-modulated radiotherapy (IMRT) for head and neck cancer (HNC) with respect to follow-up time. In addition, we explored alternative guidelines to further reduce xerostomia. Methods: The QUANTEC guideline suggests a mean dose to the contralateral (Dmeancontra) parotid