Assessment of Ki-67 proliferation index in relation to histological grades of oral squamous cell carcinoma

Abstract

Background: Oral squamous cell carcinoma (OSCC) is a frequent malignancy in the oral cavity and is associated with considerable morbidity and mortality. Proliferative markers such as Ki-67 are widely studied due to their ability to reflect tumor aggressiveness and biological behavior.

Objective: To evaluate the Ki-67 proliferation index and its correlation with different histological grades of OSCC.

Methods: This retrospective immunohistochemical study was conducted at Pathology Department of Mayo Hospital, Lahore, from January 2024 to May 2025. A total of 30 histopathologically confirmed OSCC cases were selected. Hematoxylin and sosin (H&E) stained were used for grading tumors, followed by immunohistochemical staining for Ki-67. The staining intensity and percentage of positively stained tumor cells were evaluated and scored.

Results: Among 30 cases, 6 (20 percent) showed no immunoreacitivity for Ki-67, one case exhibited mild staining, 13 cases (43.3 percent) demonstrated moderate staining, and 10 cases (33.3 percent) displayed intense Ki-67 expression. A significant positive correlation was found between higher Ki-67 expression and poor tumor differentiation (p less than 0.05). High-grade tumors (moderately and poorly differentiated OSCC) exhibited markedly increased Ki-67 labeling index as compared to well-differentiated tumors.

Conclusion: This study reinforce the utility of Ki-67 as a reliable proliferative marker in oral squamous cell carcinoma. Its expression correlates significantly with histological grade, indicating its potential role in prognostication and guiding theraputic strategies.