Factors delaying the diagnosis of oral and oropharyngeal carcinomas.

Most squamous cell carcinomas of the oral cavity and oropharynx are not diagnosed until they have attained at least the T2 stage (greater than 2.0 cm). This study identifies factors which may contribute to the delayed diagnosis of these tumors, despite the fact that they frequently arise at sites readily accessible to examination. Personal interviews of 149 patients with oral and oropharyngeal squamous cell carcinoma revealed delays by patients of one day to more than one year (mean, 17 weeks) before seeking care. Furthermore, delay by doctors occurred in 45 instances (30%). Neither short nor long delays had a statistically significant relationship to tumor T stage at the time of diagnosis. The length of patient delay was also not related to age, gender, amount of education, or history of alcohol consumption. The authors concluded that the early carcinomas were probably asymptomatic and subsequent manifestations were commonly misinterpreted as benign or innocuous oral/dental problems. These inconspicuous or misleading perceptions may be primarily responsible for the advanced stages of these tumors at the time of discovery. Emphasis must, therefore, be placed upon gaining access to high-risk individuals for periodic oral and oropharyngeal examinations and upon educational efforts to increase the skill of primary health care providers in recognizing this problem.

Absorbed radiation doses in transcranial temporomandibular joint radiography.

Lateral transcranial radiographs are commonly used to evaluate TMJ morphology and function. This study evaluated the use of four TMJ positioners in controlling the amount of radiation absorbed at predetermined sites on a phantom head. Use of positioners and collimators can reduce the amount of radiation exposure.

Changing trends of tobacco use in a teenage population in western Pennsylvania.

Information on tobacco use was obtained from an anonymous questionnaire distributed to 609 8th, 9th, and 10th grade students in the Pittsburgh area. The data disclosed that 22 per cent of the girls and 11 per cent of the boys were smoking. However, 35 per cent of the young men reported using smokeless tobacco; snuff dipping (6 per cent), tobacco chewing (10 per cent), and snuff and/or tobacco chewing (19 per cent).

Clinicopathologic effects of cancer chemotherapeutic agents on human buccal mucosa.

Specimens of buccal mucosa obtained at autopsy from 216 patients were examined for histopathologic alterations. Atrophic oral epithelium was found in thirty cases. A retrospective study of the hospital records revealed that thirteen of these latter patients had been on a cancer chemotherapeutic regimen prior to death. There was a significantly higher incidence of atrophy in the chemotherapy group (p less than 0.001) than in control patients. These findings, as well as the expected inherent susceptibility of rapidly replicating oral epithelial cells to metabolic inhibitors, suggest a causal relationship between oral atrophy and the administration of cancer chemotherapeutic agents. This atrophy may therefore represent a preliminary stage of mucosal alteration that ultimately progresses to the clinical sequelae of stomatitis and oral ulcerations frequently encountered during cancer chemotherapy. Some alternative mechanisms are also discussed.

The effect of cycloheximide on hepatic RNA synthesis and nucleolar size in rats force-fed a threonine-devoid diet.

Young rats were force-fed a complete or threonine-devoid diet for 3 days. On the fourth morning, rats of each group were injected intraperitoneally with cycloheximide (150 mug/100 g body weight) or saline with [6-14C]orotic acid 30 minutes later, 2 hours before killing. Incorporation of [6-14C]orotic acid into hepatic RNA fractions (whole homogenate, postmitochondrial supernatant, microsomes, ribosomes, nuclei and soluble) revealed elevated levels (cpm/mg RNA) in rats force-fed the threoninedevoid diet in comparison to those of rats force-fed the complete diet. However, treatment with cycloheximide decreased the incroporation of [6-14C]orotic acid into the hepatic RNA fractions of the rats force-fed the threonine-devoid diet to levels that were similar to those in rats force-fed the complete diet with or without cycloheximide treatment. Studies dealing with nucleoli isolated by sucrose gradients from livers of control and experimental rats revealed heavier nucleoli and more radioactive labeled RNA in nucleoli ([6-14C]orotic acid administered 30 minutes before killing) of rats force-fed the threonine-devoid diet than in those force-fed the complete diet for 3 days. Treatment with cycloheximide decreased the elevated incorporation in the experimental rats. Also, electron microscopic studies revealed that after cycloheximide treatment, the enlarged hepatic nucleoli of the experimental rats became smaller and returned to a more normal pattern, as found in the control rats. The studies suggest that active hepatic protein synthesis is involved in the increased hepatic RNA synthesis in rats force-fed the threonine-devoid diet and that following inhibition of protein synthesis, as induced by cycloheximide, there is a rapid inhibition of the accelerated hepatic RNA synthesis observed in rats force-fed the threonine-devoid diet with a rapid reversal toward a normal level, i.e. toward that found in control rats.

Multifocal adenoid cystic carcinoma of the lip.

A 62-year-old Caucasian woman had several distinct and separate adenoid cystic carcinomas which involved both sides of the upper lip. Microscopic examination of the surgical specimens suggested that at least one of these malignant neoplasms arose from a pre-existing basal-cell adenoma.