We set out to record the frequency of recognised adverse pathologic features in early oral squamous cell carcinoma (OSCC) and correlate with neck disease, in particular in small and thin carcinomas, a group that might be assumed to behave less aggressively. We also examined the possibility of a biopsy site interfering with assessment of WPOI5 in small tumors. We reviewed all OSCCs ≤ 20 mm size and ≤ 10 mm depth reported at our institution over a 5-year period. Tumor maximum dimension, depth, perineural invasion (PNI), lymphovascular invasion (LVI), worst pattern of invasion (WPOI), and nodal status were recorded. Out of 95 cases, there were 44 (46.3%) small and 78 (82.1%) thin OSCCs. Depth and WPOI were significant factors in predicting nodal disease. There were 41 (43.2%) OSCC that were small and thin, of which 9.8% had PNI, none had LVI, and 61% had WPOI 4 or 5. Their rate of PNI and of nodal disease was similar to the other early OSCC. Assessment of WPOI5 at a biopsy site was only a problem in 2/38 cases. In early OSCC, depth and WPOI are important factors in predicting nodal disease. The very earliest OSCC (small and thin) have a similar rate of PNI and of nodal disease to other early OSCC, suggesting that while there may be a tendency to de-escalate treatment, these small tumours should be managed in the same way as for all early OSCC. In addition, the presence of scarring due to a biopsy in very small carcinomas rarely affects assessment of WPOI5.
Keywords: Adverse pathologic features; Lymph node metastasis; Oral squamous cell carcinoma; Prognosis; Worst pattern of invasion; pT1.