1/29. osteoradionecrosis of the cervical vertebrae and occipital bone: a case report and brief review of the literature.osteoradionecrosis (ORN) is a common complication of radiation therapy. We present the first case reported in the literature of ORN involving the first and second cervical vertebrae and occipital bone in a patient who was treated with surgery and radiation therapy 9 years prior for a TxN3M0 squamous cell carcinoma of the left neck arising from an unknown primary origin. A brief review of the pathophysiology and treatment of this pathological process is also presented. Although the mandible is the most commonly affected site in the head and neck, ORN may develop in an unusual location without any preceding trauma and display an insidious but rapidly progressive course. The pathophysiology of ORN is believed to be a complex metabolic and homeostatic deficiency created by radiation-induced cellular injury and fibrosis, which is characterized by the formation of hypoxic, hypovascular, and hypocellular tissue. The irradiated bone loses its capability to increase the metabolic requirements and nutrient supply required to replace normal collagen and cellular components lost through routine wear. This results in tissue breakdown and the formation of a chronic nonhealing wound. infection plays only a contaminant role, with trauma being a possible initiating factor. diagnosis of ORN begins with a complete physical examination, including fiberoptic examination and biopsy of any suspicious lesion to eliminate the possibility of recurrent tumor. Treatment of ORN commonly requires the debridement of necrotic bone and hyperbaric oxygen therapy. The head and neck surgeon must possess a high degree of suspicion to promptly diagnose ORN and initiate early treatment. Because of similarities in clinical presentation, the most important step in the initial management of suspected ORN is to eliminate the possibility of tumor recurrence or a new primary.- - - - - - - - - - ranking = 1keywords = radiation-induced (Clic here for more details about this article) |
2/29. Lhermitte's sign following head and neck radiotherapy.Lhermitte's sign is an uncommon sequel of radiotherapy to the cervical spinal cord. Although the exact mechanism underlying its occurrence remains unclear; it is felt to be the result of a temporary interference with the turnover and synthesis of myelin, leading to focal demyelination. We have undertaken a detailed analysis of the radiation delivered to four patients who developed the sign after irradiation for malignancies of the head and neck. Our data support the view that radiation dose is crucial to its development, but calculations using the linear-quadratic radiobiological model raise interesting questions regarding the dose-response relationship. In particular, we find that calculations of biologically effective doses are predictive of a late rather than an early normal tissue response. The onset of symptoms after irradiation was apparent in all four patients within 4 months, with resolution in all being complete within a further 6 months. The recognition of this benign transient form of radiation-induced paraesthesia and its differentiation from the later onset, progressive and unremitting symptoms associated with radiation myelopathy is essential in reassuring patients undergoing head and neck irradiation.- - - - - - - - - - ranking = 1keywords = radiation-induced (Clic here for more details about this article) |
3/29. Late sequelae of radiation therapy in cancer of the head and neck with particular reference to the nasopharynx.Sequlae of radiation therapy may be late in occurring and varied in their manifestations. Although some are untreatable and progressive, the risk of development of some other sequelae can be minimized by careful application of radiotherapy or by ancillary measures, such as dental decay prophylaxis. Some of the serious sequelae secondary to radiation therapy of the nasopharynx have been summarized. These include radiation myelitis, paralysis of the cranial nerves, stricture of the pharynx, radiation-induced cancer, and necrosis with fatal hemorrhage.- - - - - - - - - - ranking = 1keywords = radiation-induced (Clic here for more details about this article) |
4/29. Candida dubliniensis in radiation-induced oropharyngeal candidiasis.Candida dubliniensis is a recently described species that has been shown to cause oropharyngeal candidiasis in patients with hiv. We present a detailed evaluation of a patient undergoing head and neck radiation for oral cancer who developed oropharyngeal candidiasis from a mixed infection of C dubliniensis and candida albicans. To our knowledge, this is the first described case of C dubliniensis contributing to oropharyngeal candidiasis in this patient population.- - - - - - - - - - ranking = 4keywords = radiation-induced (Clic here for more details about this article) |
5/29. Fetal dose during radiotherapy: clinical implementation and review of the literature.Two pregnant patients received radiation therapy, one for the treatment of mediastinal Hodgkin's lymphoma and the other for a head and neck squamous cell carcinoma. The fetuses were both protected by additional shielding which reduced the unshielded exposure of the first fetus by 20-40%, and that of the second by 20-60%. The first child received an estimated maximum dose of 42 cGy, the second a maximum dose of 9 cGy. Treatment details are reported and a review of the literature that addresses the possible irradiation-induced side effects at low doses is included.- - - - - - - - - - ranking = 1keywords = radiation-induced (Clic here for more details about this article) |
6/29. baroreflex failure as a late sequela of neck irradiation.Combined chemotherapy and radiotherapy increase long-term survival in patients with head and neck tumors. Late complications of treatment, however, are being recognized increasingly. Surgery or radiotherapy of the carotid sinuses or brain stem can evoke labile hypertension and orthostatic intolerance from acute or subacute baroreflex failure. Here we report cases in which chronic baroreflex failure appeared to develop as a late sequela of neck irradiation. Three patients referred for autonomic nervous system function testing had labile blood pressure and chronic orthostatic intolerance that developed years after neck irradiation for cancer. In each patient, heart rate remained constant during performance of the valsalva maneuver, suggesting baroreflex-cardiovagal failure. All 3 patients had virtually zero baroreflex-cardiovagal gain, quantified by interbeat interval-systolic blood pressure relationships after intravenous phenylephrine or nitroglycerine. Ambulatory blood pressure monitoring revealed highly variable blood pressure, with sudden pressor and depressor episodes, a characteristic feature of baroreflex failure. Cardiovagal efferent function, assessed by power spectral analysis of heart rate variability during slow, deep respiration, was normal. Sympathetic noradrenergic efferent function, assessed by cold pressor testing and plasma catecholamine levels during supine rest and orthostasis, was also normal or increased. These findings indicated a primarily afferent lesion. Carotid ultrasonography revealed intimal thickening and atheromatous plaques in all 3 patients. We propose that labile hypertension and orthostatic intolerance can develop as a late sequela of neck irradiation, due to chronic carotid baroreflex failure, which in turn is due to radiation-induced accelerated development of carotid arteriosclerosis. Splinting of carotid sinus mechanoreceptors in rigidified arterial walls would impede detection of alterations in blood pressure and thereby disrupt baroreflex regulation of cardiovagal and sympathetic outflows.- - - - - - - - - - ranking = 1keywords = radiation-induced (Clic here for more details about this article) |
7/29. Synchronous basal cell carcinoma and meningioma following cranial irradiation for a pilocytic astrocytoma.We report a case of synchronous radiation-induced meningioma and basal cell carcinoma in a 48-year-old man who presented to the plastic surgeons with a fixed scalp lesion sited over a craniotomy scar. Synchronous radiation-induced tumours are a rare occurrence.- - - - - - - - - - ranking = 2keywords = radiation-induced (Clic here for more details about this article) |
8/29. Irradiation-induced polyglandular neoplasia of the head and neck.Eighteen patients are presented with twenty-one tumors of the head and neck, which include ten salivary gland tumors and eight parathyroid adenomas. Eight of the patients also had thyroid neoplasms. All patients had a history of prior irradiation to the head and neck. Seventy per cent of the salivary gland tumors and 37 per cent of the thyroid tumors were malignant. Recommendations are made for detection and treatment.- - - - - - - - - - ranking = 4keywords = radiation-induced (Clic here for more details about this article) |
9/29. Malignant fibrous histiocytoma of the head and neck after radiation for squamous cell carcinoma.A 60-year-old man presented with malignant fibrous histiocytoma of the oropharynx. The mass extended into the nasopharynx and larynx and caused severe upper airway obstruction that required emergency tracheotomy. Ten years earlier, he had undergone a right partial glossectomy and segmental mandibulectomy for squamous cell carcinoma of the right tongue base,followed by 50 Gy of radiation delivered over 33 sessions. The tumor was so aggressive that changes in its volume were visually distinguishable during physical examination over a 2-week hospital stay. Histologic evaluation revealed 7 mitotic figures per high-power field. Although radiation-induced malignant fibrous histiocytoma is rare in the head and neck, the recent medical literature indicates that its incidence is rising. This rise has been attributed to the increased effectiveness of head and neck cancer therapy, which results in prolonging patients' survival and, hence, their risk of subsequent disease. Because malignant fibrous histiocytoma is a late complication of radiation therapy, appearing on average 10 years following treatment, it is important that physicians who treat head and neck cancer monitor these patients over the long term and remain alert for its appearance, even despite the apparent "cure" of their original neoplasm.- - - - - - - - - - ranking = 1keywords = radiation-induced (Clic here for more details about this article) |
10/29. Irradiation-induced atherosclerosis: a factor in therapeutic planning.Early primary head and neck cancers (stages I and II) and occult metastatic neck disease have caused debate regarding the choice between surgery and irradiation. The arguments for each are reviewed with a new consideration: the acceleration and/or induction of carotid atherosclerosis in irradiated patients. We present clinical case reports (n = 9), a retrospective clinical evaluation for the occurrence of carotid atherosclerosis in irradiated head and neck cancer patients (n = 57) and a comparison study of the extent and distribution of atherosclerosis in irradiated (n = 29) and nonirradiated head and neck cancer patients controlled for age, blood pressure, and tobacco use. The results show that carotid atherosclerosis is found in a wider anatomic distribution and to a greater extent in irradiated than in nonirradiated patients. We conclude that carotid atherosclerosis is induced and/or accelerated by neck irradiation. The implications as they relate to choice of treatment, to pretreatment evaluations, and to long-term follow-up are discussed.- - - - - - - - - - ranking = 4keywords = radiation-induced (Clic here for more details about this article) |
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