Rahul, 51-yrs-old who has chewed tobacco for more than 20 years
presents with a slowly enlarging mass on the floor of his mouth.
Examination finds the mass, 1.3 cm in greatest dimension, white in color
and irregular in appearance. Biopsies from this lesion aremost
likely to reveals which one of the following malignancies?
A. Acinic cell carcinoma
B. Adenocarcinoma
C. Basal cell carcinoma
D. Squamous cell carcinoma
likely to reveals which one of the following malignancies?
A. Acinic cell carcinoma
B. Adenocarcinoma
C. Basal cell carcinoma
D. Squamous cell carcinoma
198. Ans. D. Squamous cell carcinoma
· Carcinoma of the oral cavity accounts for approximately 5% of all human
malignancies. More than 90% of oral carcinomas are of the squamous cell type;
precursor lesions include leukoplakia (dysplastic leukoplakia) and
erythroplasia, with transformation rates of approximately 15 and 50%, respectively Oral carcinoma is more common in males.
erythroplasia, with transformation rates of approximately 15 and 50%, respectively Oral carcinoma is more common in males.
· Smoking, tobacco chewing, chronic irritation, heat exposure, and
irradiation are all thought to contribute to carcinogenesis.
· The lower lip is the most common site, followed by the floor of the
mouth, the anterior tongue, the palate, and the posterior tongue.
· Prognosis varies according to site but is best for lesions of the lip and
worst for lesions in the floor of the mouth.
· In contrast, acinic cell carcinoma is a type of malignancy of the
salivary glands, while basal cell carcinoma is the most common malignancy of
the skin, and small cell carcinoma is a type of primary lung carcinoma.
