Oral mucosal melanomas: the WESTOP Banff workshop proceedings. Western Society of Teachers of Oral Pathology.

A workshop to discuss primary oral melanomas was convened at the annual Western Society of Teachers of Oral Pathology meeting in Bannf, Alberta, Canada. Fifty oral melanomas, identified from the files of the participants, were reviewed in order to better understand the clinical features, histologic spectrum, and natural history of these perplexing lesions. Results confirmed that oral melanomas occur in adults almost three times more frequently in men than women and have a decided predilection for the palate and gingiva. Some lesions exhibit a clinically detectable and prolonged in situ growth phase, whereas others seem to lack this property and exhibit only or predominantly invasive characteristics. Recurrences, metastases, and death from tumor were characteristic of the follow-up of a limited number of patients. Until definitive prospective data are collected that elucidate natural history, oral mucosal melanomas should be tracked separately from cutaneous lesions. All oral pigmented lesions that are not clinically diagnostic should be biopsied. Lesions with equivocal histopathologic features might be referred to as "atypical melanocytic proliferation" and should be excised. Recognition of lesions in an early in situ phase and aggressive treatment should have a favorable effect on prognosis. To enhance future or prospective study of these rare neoplasms, guidelines for reporting oral melanomas are suggested.

Oral cancer. Etiology, recognition, and management.

The cure rate for oral cancers remains dismally low at approximately 50%. The dental profession is, to a large extent, responsible for decreasing the morbidity and mortality of oral cancer even though 50% of the population do not present for routine examination and care. The dental office team must accept the charge of educating all patients concerning the devastating role of tobacco and ethanol in promoting oral cancer, as well as malignancies at other sites. Dental clinicians play a vital role on the oral cancer team. Therefore, they must make themselves well aware of the diverse nature of oral cancer and must have an appropriate triage protocol in place so that lesions will be identified and managed correctly or referred promptly to the correct tertiary health care professionals. Early detection and prompt proper management can make a difference as we await the development of new and better ways of treating oral and oropharyngeal cancers.

An ancient "tumour" from pre-Columbian Chile.

A case of an expansile facial lesion discovered in the more than 600 years old skeletal remains of a 22-25-year-old female is discussed. Gross, radiographic and histological studies were accomplished on the specimen. Although a definitive diagnosis could not be derived because of the age and condition of the specimen, differential diagnoses are discussed and a probable diagnosis rendered.

A condylar tumor from pre-Columbian Chile: a case report.

A case of an expansile, multilocular lesion in a condyle recovered in skeletal remains more than 700 years old is discussed. Gross, radiologic, and histologic studies were accomplished on the specimen. Although a definitive diagnosis could not be arrived at because of the age of the specimen, differential diagnoses are presented.

Hamster cheek pouch carcinoma: effect of incision and cortisone on growth, invasion, and metastasis.

After cheek pouch carcinomas were induced in hamsters by the application of dimethylbenzanthracene (DMBA) to the right pouch for 13 weeks, the animals were divided into four groups and observed for seven more weeks. The control group received no further treatment, two experimental groups had incisional biopsies performed on tumors in their pouches, one of these also received injections of cortisone throughout the 20-week experimental period, and a fourth group received cortisone only. The wet weights of the cancerous cheek pouches were determined, and the submandibular and parotid salivary glands with associated cervical lymph nodes, the lungs, and the liver were examined with light microscopy. The cancerous pouches of the animals that received cortisone weighed significantly less than those of animals that received no cortisone but had incisional biopsies of the tumors. There was no significant difference in the degree of histodifferentiation of the tumors among the four groups. The animals in the two groups that received cortisone had significantly more tumors that were invasive than did the animals that did not receive cortisone. Cervical lymph node metastasis occurred in 21% to 38% of the animals but was not significantly different in the four groups. Distant metastases to the lungs or the liver were not found. Incisional biopsy of the tumors stimulated local growth of the cheek pouch tumors, and systemic cortisone administration produced more invasive cheek pouch tumors.

Incisional biopsy and seeding in hamster cheek pouch carcinoma.

Surgical blades were contaminated by doing incisional biopsies on DMBA-induced cheek pouch carcinomas in hamsters. Contaminated blades were then used to: (1) make cytologic smears; (2) make incisions in the mucosal surface of the lower lip; (3) make incisions in the ventral surface of the tongue; (4) make incisions in the untreated left cheek pouch; and (5) make incisions in the pre-shaved back. One group of animals was killed three hr post-surgery. The second group was killed seven wk post-surgery. Tissues were excised and processed for microscopic study. Malignant cells were found in many of the incision sites of animals from the first group. In the animals of the second group, several tumors growing from the transplanted tumor cells were observed in the incision sites of the lower lips and the tongue. None was observed in the incision sites of the left cheek pouch or the back. Cervical lymph node metastases were found in approximately 50% of the animals of the second group.

Cleft palate induction: quantitative studies of 3H corticoids in A/Jax mouse tissues after maternal injections of 3H cortisol.

A/Jax mice were injected with 50 muCi of 3H cortisol and 10 mg of cortisone acetate on day 12 of gestation. At various intervals after injection, the maternal liver, placenta, yolk sac, and the fetal jaws were removed and analyzed by thin-layer chromatography in conjunction with oxidative combustion and liquid scintillation counting to identify and measure the amount of labeled corticoid metabolites. The results support the thesis that these corticoids may induce clefts by an individual or combined direct action on the fetal jaws and palatal shelf tissue.