The efficacy of hyperbaric oxygen therapy related to the clinical stage of osteoradionecrosis of the mandible.

This study aimed to evaluate the success of hyperbaric oxygen therapy (HBOT) and surgery in the treatment of mandibular osteoradionecrosis (ORN) in relation to the extent of the ORN. Twenty-seven patients with ORN were identified from a total of 509 patients with a history of primary oral or base of the tongue cancer; these patients had been treated with radiation therapy with curative intent between 1992 and 2006, with a radiation dose to the mandible of ≥50Gy. The ORN was staged according to the classification of Notani et al. The time from completion of radiation therapy to the development of ORN varied (median 3 years). Forty HBOT sessions were offered. After HBOT alone, 3 of 11 stage I lesions, 0 of 8 stage II lesions, and 0 of 8 stage III lesions had healed (P=0.0018). An absolute incidence of 5.3% ORN was found in this population. Of all sites irradiated in this study, the floor of the mouth was most associated with ORN (8.6%), whereas the cheek was least associated (0%). Based on the results of this study, HBOT can be recommended for stage I and II ORN and for selected cases of stage III ORN.

Interforaminal implant placement in oral cancer patients: during ablative surgery or delayed? A 5-year retrospective study.

In a retrospective study, two mandibular prosthetic rehabilitation strategies supported by implants in oral cancer patients were evaluated: implants placed in the non-resected edentulous symphyseal area during ablative surgery (DAS implants); or at a later stage (postponed (P) implants). Medical files of patients from two head-neck oncology groups from 2000 to 2005 were screened for study inclusion. DAS protocol was used in one group and P protocol in the other. After a 5 year follow-up of 261 edentulous patients with oral cancer in the second group, P implants were placed in 27 patients to support an overdenture. Of the 249 edentulous patients in the first group, 82 patients were given an implant supported overdenture using the DAS implant protocol. Regarding implant loss, no statistically significant differences were seen between the DAS and P implants. In the DAS group, more patients benefited from an implant-supported lower overdenture (39 versus 11%, respectively), and they received their overdenture on average 20.0 months sooner (sd=11.01, p<0.001) after ablative surgery. 17.1% of DAS implants and 4.6% of P implants were never loaded due to tumour and patient related factors including unfavourable implant soft tissue, tumour recurrence near the implant, or radiotherapy induced trismus.

The effect of hyperbaric oxygen therapy on quality of life in oral and oropharyngeal cancer patients treated with radiotherapy.

Radiotherapy is used in the setting of curative treatment for head and neck cancer. Xerostomia and related problems occur when major salivary glands are included in the irradiation fields. This reduces quality of life (QOL). Hyperbaric oxygen therapy (HBOT) is a well accepted treatment or prevention modality for osteoradionecrosis of the jawbones and soft-tissue necrosis. It is unknown if and to what extent HBOT influences xerostomia and xerostomia-related QOL. To address this, a prospective study was conducted. Twenty-one patients who underwent radiotherapy for an oral or oropharyngeal carcinoma completed a European Organization for Research and Treatment of Cancer QOL questionnaire before HBOT, as part of the treatment/prevention of osteoradionecrosis, and 1 and 2 years after HBOT. Swallowing-related problems significantly decreased in time, and there was a reported subjective increase in saliva quantity and an improvement in sense of taste. The results suggest that HBOT may positively influence these long-term radiotherapy sequelae.

The hypoxic tumour microenvironment, patient selection and hypoxia-modifying treatments.

Tumour hypoxia has been found to be a characteristic feature in many solid tumours. It has been shown to decrease the therapeutic efficacy of radiation treatment, surgery and some forms of chemotherapy. Successful approaches have been developed to counteract this resistance mechanism, although usually at the cost of increased short- and long-term side-effects. New methods for qualitative and quantitative assessment of tumour oxygenation have made it possible to establish the prognostic significance of tumour hypoxia. The ability to determine the degree and extent of hypoxia in solid tumours is not only important prognostically, but also in the selection of patients for hypoxia-modifying treatments. To provide the best attainable quality of life for individual patients it is of increasing importance that tools be developed that allow a better selection of patients for these intensified treatment strategies. Several genes and proteins involved in the response to hypoxia have been identified as potential candidates for future use in predictive assays. Although some markers and combinations have shown potential benefit and are associated with treatment outcome, their clinical usefulness needs to be validated in prospective trials. A review of published studies was carried out, focusing on the assessment of tumour hypoxia, patient selection and the possibilities to overcome hypoxia during treatment.