Regional behavioral variations of epidermoid carcinoma of the head and neck: a study in an animal model.

Regional behavioral differences have been observed clinically in epidermoid carcinoma of the head and neck. An animal model was developed for study, using homograft, transplanted epidermoid carcinoma in Fisher rats. Histopathologic review of tumors of the palate, base of tongue and larynx shows cartilage, arterial wall, surface epithelium and dense connective tissue containing elastic fibers to be relatively resistant to tumor invasion. Muscle, bone, vein and loose connective tissues were easily invaded. This correlates well with the known biochemical and immunological events in tumor invasion and host-tumor interactions. Regional metastasis occurred in two animals with base of tongue tumors. No distant metastases were found.