Which histologic type is the most common malignant tumor of the oral cavity?

Which histologic type is the most common malignant tumor of the oral cavity?

• A. Adenocarcinoma
• B. Melanoma
• C. Sarcoma
• D. Squamous cell carcinoma

Answer: (D)

The oral cavity is lined mainly by stratified squamous epithelium, so malignant tumors here most often arise from those squamous cells. Squamous cell carcinoma reflects this origin and is the most common malignant tumor in the mouth. Under the microscope, you see malignant squamous cells growing in nests or sheets, frequently with keratinization (keratin pearls) in well-differentiated forms, and invasion through the basement membrane into surrounding tissues. This makes it the prevailing histologic type for oral cancers. Other options correspond to different tissue sources not typical for the oral mucosa: adenocarcinoma comes from glandular tissue, melanoma from pigment-producing melanocytes, and sarcoma from connective tissues. While those can occur in the head and neck region, they are far less common in the oral cavity compared with squamous cell carcinoma.

The oral cavity is lined mainly by stratified squamous epithelium, so malignant tumors here most often arise from those squamous cells. Squamous cell carcinoma reflects this origin and is the most common malignant tumor in the mouth. Under the microscope, you see malignant squamous cells growing in nests or sheets, frequently with keratinization (keratin pearls) in well-differentiated forms, and invasion through the basement membrane into surrounding tissues. This makes it the prevailing histologic type for oral cancers.

Other options correspond to different tissue sources not typical for the oral mucosa: adenocarcinoma comes from glandular tissue, melanoma from pigment-producing melanocytes, and sarcoma from connective tissues. While those can occur in the head and neck region, they are far less common in the oral cavity compared with squamous cell carcinoma.