Between March 1973 and June 1979, patients with advanced operable squamous cell carcinoma of the supraglottic larynx or hypopharynx were randomly allocated to receive either preoperative radiation therapy (5,000 rad) or postoperative radiation therapy (6,000 rad). Patients with oral cavity or oropharynx lesions were randomly assigned either preoperative radiation, postoperative radiation, or definitive radiation therapy (6,500-7,000 rad), with surgery reserved for salvage if residual disease was present 6 weeks after completion of irradiation. Three hundred twenty patients were evaluable with a median follow-up of 60 months. Based on results in 277 patients across all four regions combined, locoregional control was significantly better for patients assigned to receive postoperative radiation therapy (65%) compared with those assigned to receive preoperative radiation therapy (48%, P = 0.04). This was due to a higher rate of both persistent and recurrent local and regional disease in the preoperative group. Survival also showed a trend to be better in the postoperative group (38%) compared with the preoperative group (33%, P = 0.10). Rates of severe surgical and radiation therapy complications were similar overall. Forty-three patients were evaluable for each of the three treatment regimens assigned to patients with oral cavity or oropharynx lesions. Due to the small number of patients available for this portion of the trial, the observed differences for overall survival (4-year percentage 33% overall; 30% preoperative, 36% postoperative, 33% definitive radiation therapy) and for locoregional control (45% overall; 43% preoperative, 52% postoperative, 38% definitive radiation therapy) were not statistically significant. The use of definitive radiation therapy with surgical rescue as an ethically justified alternative treatment for these tumors remains a question for further research.
\s=b\Human olfactory neuroepithelium and respiratory mucous membrane in fetal and adult whole-mount sections were studied. In the fetus, the olfactory neuroepithelium extends from the roof of the nasal cavity to the midportion of the nasal septum and onto the superior turbinate in a continuous fashion. In the adult, the zonal distribution of supporting, sensory receptor, and basal cells is frequently disrupted, and the supporting and sensory receptor cells are often depleted or degenerate. The degree of the degeneration of the adult olfactory neuroepithelium varies from case to case. The most striking feature in the adult is the replacement of large areas of olfactory neuroepithelium with respiratory epithelium. The extensive replacement of olfactory neuroepithelium with respiratory epithelium points out the sampling problem related to small, random biopsy specimens of the olfactory area.
Hypocalcemia, although a relatively uncommon sequela of operations for carcinoma of the larynx and pharynx, often presents as an acute medical emergency. In its chronic form, hypocalcemia may be a difficult disorder to control. Understanding the etiologic basis of hypocalcemia secondary to operations for carcinoma of the head and neck requires knowledge of the pathophysiology of the preoperative and postoperative factors affecting calcium homeostasis. These factors include thyroidectomy, hypoparathyroidism, hypomagnesemia, anticonvulsant therapy, estrogen replacement therapy, oral contraceptives, blood transfusions, hyperventilation alkalosis, hypoalbuminemia, corticosteroid therapy, depression, emotional stress and diet. Often the onset of symptoms and signs of hypocalcemia occurs within 24 to 48 hours after the operation. The symptoms may include mental depression, headache, tingling of the hands and perioral region and abdominal pain. Unrecognized chronic hypocalcemia may lead to the development of cataracts, convulsions and psychosis.
The electrophysiologic and histopathologic changes in the inner ear caused by the administration of cis-diamminedichloroplatinum (CP) were studied in guinea pigs. The endocochlear dc potential (EP) gradually decreased after the intravenous injection of CP and reached approximately 0 mV on the fourth day, but the EP did not become negative. The cochlear microphonics also diminished and could not be recorded on the fourth day. The negative potential of the organ of Corti remained in the normal range during the experiment. A large negative summating potential (SP) was observed one day after injection, but the amplitude of the negative SP became small on the second day. Light microscopic examination demonstrated that the outer hair cells are destroyed in the basal turn of the cochlea and are preserved in the upper turns, while the inner hair cells are almost completely preserved in all turns. The stria vascularis was found to be slightly atrophic. Severe collapse of Reissner's membrane was observed in the basal turn.
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