Osteoradionecrosis of the mandible: a case series at a single institution.

BACKGROUND: Osteoradionecrosis (ORN) defines exposed irradiated bone, which fails to heal over a period of 3-6 months without evidence of residual or recurrent tumor. In the previous decades, a staging and treatment protocol suggested by Marx, has dominated the approach to ORN. However, recently this paradigm is shifting. The purpose of this study was to evaluate our institutional experience in managing ORN through a retrospective review of case series from a large urban academic cancer centre. METHODS: A retrospective chart review was conducted to include all ORN cases from 2003 to 2009 diagnosed at the Department of Otolaryngology - Head and Neck Surgery and the Department of Dentistry. The staging of ORN was assessed as affected by tumor site, tumor stage, radiotherapy modality and dose, chemotherapy, dental work, and time to diagnosis. The effectiveness of hyperbaric oxygen therapy (HBO) and surgery in the management of ORN was evaluated. RESULTS: Fourteen cases of ORN were documented (incidence 0.84%). Primary subsites included tonsils, tongue, retromolar trigone, parotid gland, soft palate and buccal mucosa. There were 5 (35.7%) stage 1, 3 (21.4%) stage 2, and 6 (42.9%) stage 3 cases. ORN severity was not significantly associated with gender, smoking, alcohol use, tumor site, T stage, N stage, AJCC stage, or treatment modality (radiation alone, surgery with adjuvant radiation or adjuvant chemoradiation). Patients treated with intensity-modulated radiotherapy developed less severe ORN compared to those treated with conventional radiotherapy (p < 0.015). ORN stage did not correlate with radiation dose. In one patient only dental procedures were performed following radiation and could be implicated as the cause of ORN. HBO therapy failed to prevent ORN progression. Surgical treatment was required for most stage 2 (partial resections and free tissue transfers) and stage 3 patients (mandibulectomies and free tissue transfers, including two flaps in one patient). At an average follow up of 26 months, all patients were cancer-free, and there was no evidence of ORN in 84% of patients. CONCLUSIONS: In early ORN, we advocate a conservative approach with local care, while reserving radical resections with robust reconstruction with vascularized free tissue for advanced stages.

The role of intraoperative rapid parathyroid hormone monitoring for predicting thyroidectomy-related hypocalcemia.

OBJECTIVE: To determine if the intraoperative rapid parathyroid hormone (PTH) assay can be used to accurately predict postoperative calcium levels following total or completion thyroidectomy. DESIGN: A prospective study. SETTING: Tertiary care referral center. PATIENTS: One hundred four patients following a total or completion thyroidectomy.Intervention Intraoperative rapid plasma PTH levels were determined for patients undergoing a total or completion thyroidectomy. MAIN OUTCOME MEASURES: Parathyroid hormone levels were recorded after the induction of anesthesia, before excision, and 5, 10, and 20 minutes after thyroidectomy. Postoperative calcium levels were monitored every 6 hours until hospital discharge. Intraoperative PTH levels were correlated with postoperative calcium levels and clinical symptoms of hypocalcemia. RESULTS: Twenty-two patients (21.2%) required short-term postoperative calcium supplementation, and 2 (1.9%) required long-term calcium replacement. There was a statistically significant difference between those patients requiring calcium replacement and those who did not require calcium supplementation, for postoperative total calcium level (7.2 vs 8.1 mg/dL [1.8 vs 2.0 mmol/L]; P<.001) and ionized calcium level (3.76 vs 4.36 mg/dL [0.94 vs 1.09 mmol/L]; P<.001). In addition, the PTH changes from baseline demonstrated statistically significant differences at 5, 10, and 20 minutes after the excision between the 2 groups (P<.005). In those patients requiring calcium supplementation, 14 (64%) of 22 demonstrated a change in PTH level at 20 minutes of greater than 75% from baseline, and in those patients who did not require postoperative calcium supplementation, 61 (74%) of 82 demonstrated a change in PTH level of less than 75% from baseline (P<.005). CONCLUSION: Intraoperative PTH monitoring may be a useful tool in identifying patients who will not require postoperative calcium supplementation following total or completion thyroidectomy.