Histologic correlates of metastasis in primary invasive squamous cell carcinoma of the lip.

Clinical and histologic features of 44 invasive squamous cell carcinomas of the lip treated by surgical excision were correlated with metastases and survival. Age, diameter, ulceration, grade, depth of invasion, muscle invasion, mitotic rate, lymphatic-vascular invasion, and tumor infiltrating lymphocytes were evaluated. Two (4.5%) patients had local recurrence, 10 (23%) had metastases to cervical lymph nodes, and 2 (4.5%) died from complications of extensive spread in the neck. One patient with local recurrence had regional node metastases. Regional metastases were discovered at the time of (3 patients) or up to 21 (median 8) months after initial diagnosis, correlating with ulceration (P = 0.003), depth of invasion (P = 0.0001), and mitotic rate (P = 0.05) of the primary tumor. Depth exceeding 2.0 mm. was associated with metastasis (P = 0.028), and all carcinomas deeper than 6.0 mm. metastasized. Eight of the 10 patients with regional metastases had no further disease after treatment through the follow-up period (median 64 months). Both fatalities were older (median 81 years) men. These results underscore the metastatic potential of invasive squamous cell carcinoma of the lip. Histologic analysis of the primary lesion can be used to identify individuals at risk.