Aims: To test the validity of an invasive pattern
grading score (IPGS) developed for oral squamous cell
carcinoma (OSCC) as a prognostic indicator and to
elucidate the relationship between the IPGS and
clinical parameters.
Methods and results: The IPGS was applied to a total of
153 cases of OSCC. There were significant correlations
between IPGS and distant metastasis (P = 0.01) or
recurrence (P = 0.001). However, there were no significant
correlations between IPGS and gender, age,
size or extent, location, status of lymph node metastasis,
clinical staging, or histological grading. Cases of
OSCC with higher IPGS were associated with poor
patient survival (P < 0.001) and higher probability of
tumour recurrence (P = 0.001). Intraobserver (j =
0.74) and interobserver agreement (j = 0.67) were
very satisfactory.
Conclusions: Our study confirms the validity of the
IPGS, an indicator that is simple and easy to use. IPGS
not only provides histological assessment of biological
behaviour, but also offers an independent prognostic
factor that may influence the treatment of OSCC.
