Relevance of Tumor Budding and Pattern of Invasion in Oral Squamous Cell Carcinoma.

Background: Standard histopathological parameters such as depth of invasion (DOI), lymphovascular invasion (LVI), and perineural invasion (PNI) are known parameters that can correlate with the prognosis and aggressiveness of oral squamous cell carcinomas (OSCCs). Tumor budding (TB) (≤5 tumor cells at infiltrating borders) and pattern of invasion (POI) are emerging histopathological parameters that have shown promising results as reliable risk factors in predicting nodal metastasis in early OSCCs. Aim: The aim of the study was to assess TB and POI in OSCCs. Materials and Methods: A total of 33 surgical resection specimens of OSCC, including buccal mucosa and tongue with neck dissection, were selected. TB and POI along with standard parameters such as grade, DOI, LVI, PNI, lymph node status, and pathological staging were evaluated. These parameters were analyzed in comparison with lymph node involvement and pathological stage of the tumor using the Chi-square and Fischer's exact test. The SPSS software, v21, was used for statistical analyses. Results: Most of OSCC were moderately differentiated tumors (63.64%). TB was present in 23 cases, in which 69.57% of cases showed low TB (<5 buds), while 30.43% of cases had higher TB (>5 buds). The worst POI (Patterns 4 and 5) was seen in 75.76% of cases. TB, POI, grade, PNI, DOI, and stromal pattern were significantly associated with the pathological stage of the tumor. Conclusion: TB and POI are important and reliable in histopathological parameters in OSCCs.