The prognosis for squamous carcinoma of the floor of the mouth is adversely affected by which of the following?Composite resection specimen of a T4 floor of mouth squamous cell carcinoma: (A) Poor differentiation of tumor, (B) Nonverrucous carcinoma, (C) Presence on left side, (D) No tongue involvement
Answer is A. Poorly differentiated squamous cell carcinoma of the floor of the mouth tends to be more invasive than better-differentiated tumors. Poorer prognosis can be expected when invasion is larger than 9 mm, perineural invasion is noted, and lymph node metastasis is evident.