While tumor suppressor genes at 3p (VHL), 13q (RB), and 17p (p53) have been identified, altered genes at other loci on 3p and on 8p have not yet been characterized. Furthermore, the genotype at these loci for squamous cell carcinoma of the upper aerodigestive tract has prognostic importance and may identify the patients who should receive the most aggressive treatment.

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Human papillomaviruses (HPVs) have been identified in benign and cancerous epithelial lesions of the female genital tract. They have also been identified in papillomata and cancers of the upper aerodigestive tract. This study investigates the hypothesis that lesions of the cervicovaginal area are more common in women with cancers of the head and neck region. The presence of HPV in lesions of both regions is examined. Seven female patients with cancer of the upper aerodigestive tract had DNA analysis of their carcinoma specimens. HPV type 16 was found in two of the seven (28%). Fourteen female patients with upper aerodigestive tract cancers had Papanicolaou smears to search for cytologic evidence of HPV infection, and cervicovaginal lavages to analyze DNA from exfoliated cervical cells. Five of thirteen (38%) Papanicolaou smears revealed koilocytotic atypia and three of these patients had HPV DNA types 16 or 18 identified in the cervical lavage. The incidence of cervical atypia noted is 13-fold greater than average. One patient had HPV type 16 in both her supraglottic cancer and in her cervicovaginal lavage. Evidence of HPV infection at two separate anatomic sites suggests a systemic susceptibility to HPV infection.

We have discussed oncogenes and their protein products which act at various sites in tumor cells, with special consideration for tumors of the head and neck. In a few systems studied, application of this knowledge has led to preliminary therapeutic interventions. While abnormal expression and function of these genes and proteins are responsible for transformation to the malignant phenotype, further study of these oncogenes will also help illuminate the mechanisms of normal cellular growth and differentiation. Although cancers of the upper aerodigestive tract are heterogeneous in origin and the multi-step process of carcinogenesis is likely to vary in different tumors, the head and neck tumor spectrum is a good model for tumorigenesis and should provide valuable insight into general carcinogenesis and normal cellular growth controls.

Upper aerodigestive tract (UADT) cancers provide an excellent carcinogenesis model for a number of reasons: they are accessible to observation, are usually associated with a known environmental carcinogen (tobacco by-products), are sometimes associated with a tumorigenic DNA virus (HPV), and fall along a spectrum of progressive disease from normal mucosa through leukoplakia and verrucous carcinoma to invasive and metastatic carcinoma. Despite the presence of this unique model, the field of head and neck oncology, as a whole, has been slow in establishing an efficient 2-way conduit between the bedside and the laboratory. Such open communication is important as current evidence suggests that future staging and therapy of head and neck tumors will depend not only on familiar macroscopic and light microscopic criteria, but also on factors that are currently identifiable only in the basic science laboratory. To have a significant impact on the direction and relevance of basic research, clinicians should become knowledgeable and conversant in the vocabulary and general concepts of basic science. The goal of this section is to facilitate communication between the basic researcher and the clinician, thereby promoting clinically relevant basic research. This is to be achieved by fostering understanding of the power, limitations, scope, and horizons of current basic research concepts and techniques. Subsequent articles will review current research topics germane to head and neck cancer, such as oncogenes and tumor suppressor genes, mechanisms of metastasis, tumor immunology and its modulation, and virology.