System: Head and Neck: Oral Cavity: Neoplastic: Squamous cell carcinoma (Floor of Mouth)
Invasive nests of malignant squamous cells, which can range from well-differentiated to poorly differentiated. This case is fairly well-differentiated. See the keratin pearls?
Invasion of tumor cells elicits a prominent desmoplastic reaction in the stroma. Note the central necrosis.
Other areas again show a cohesive tumor with pleomorphic nuclei and focal keratinization.
In a cervical node, metastatic squamous cell carcinoma is seen.
Aspiration of the nodes clearly shows a diathesis background with some keratin debris.
The pap stained smear of the lymph node shows enlarged overlapping cells with eosinophilia to the cytoplasm.
Malignant squamous cells seen in the diff-quick stain show large hyperchromatic, dense nuclei; coarse chromatin; and abundant keratinizing glassy cytoplasm; and a necrotizing background with keratin debris
Oral cancers include three anatomic regions: the lip vermilion, oral cavity proper and oropharynx.
Squamous cell carcinoma is the most common malignancy of the oral cavity and oropharynx with 25,000 new cases each year. Most often occurs after age 50, with a male to female ratio of 3:1 and a higher incidence in blacks. Smoking is a strong risk factor and alcohol in combination with tobacco further potentiates the risk. In some countries, chewing betel nuts is a risk factor. Long-term sun exposure is a risk factor for squamous cell on the lip.
In the oral cavity proper, the most common locations are the lip, followed by tongue, floor of mouth, gingiva, palate and buccal mucosa. In the oropharynx, the tonsils and base of tongue is most commonly affected.
May present as premalignant lesions (leukoplakia and/or erthyroplakia) which can evolved into large ulcers. Erthyroplakia is more worrisome than leukoplakia (1). Invasive carcinomas can appear as depressed ulcers or fungating exophytic masses.
Overall 5-year survival is 50-55%, although it is highly dependent on location and stage. Stage I has a survival rate of 80-90%, but stage III or IV, the rate drops to 30% (CONFIRM). Unfortunately, 30% of patients have with metastatic disease at initial presentation. (1)