Assessing the Utility of Actual Proliferation Index Measured by Expression of ‘Agnor and Ki-67’ in Histopathologically Negative Surgical Margins of Oral Squamous Cell Carcinoma as a Modality for Prediction of Recurrence

Background: Oral squamous cell carcinoma is most common malignancy of head and neck which is the major cause of death. Recurrence is the major important prognostic factor in the survival of patients and tumor stage, degree of differentiation of neoplastic cells, pN stage resected margins, and lymphovascular invasion are the factors for recurrence. The rate of recurrence varies from 18 to76% for patients who underwent standard treatment. Histological assessment of surgical margins has a major role to predict the recurrence. But in spite of negative histological surgical margins recurrence rate is high, as there are genetic alterations in these margins which are not detected by routine histopathlogy. Even when surgical margins are free histopathologically the local recurrence rate is 10 to 30 percent.

That’s why molecular evaluation of these margins should be done. Many immunohistochemical studies are done to assess surgical margins of OSCC but no study is carried out to assess the proliferative index in surgical margins. Therefore this study will help to improve management and predict the recurrence of OSCC.

Objectives: In this study we aim to assess the utility of “actual proliferation index” measured by expression of “Agnor” and “Ki-67” in histopathologically negative “surgical margins” of “oral sqaumous cell carcinoma” as a modality for prediction of recurrence.

Methodology: The resected surgical margins of the oral squamous cell carcinoma cases which are operated in Sharad Pawar dental college will be selected as samples. The anterior, posterior, inferior and superior margin of resected specimens will be stained by H&E staining. Immunohistochemical staining by ki-67 antibody will be done in the negative histopathological surgical margins. The same sections will be stained with AgNOR staining. Both sections will be evaluated. Actual proliferative index will be calculated with the given formula

Ki67 Labeling Index: Ki67 L1= “Number of Ki67 positive cells” x 100

Total number of tumor cells observed

“Actual Proliferative Index (PI)” = “ Ki-67” or MIB-1 LI × AgNOR count ’

Recurrence of tumor will be observed during first two years period after surgical procedure.

Expected Results: The “actual proliferative index” calculated by “Ki-67 labelling index” and “AgNOR count expression in histopathologically” negative surgical margins of OSCC will be more in recurrence patients as compared to patients who do not have recurrence.

Conclusion: The API values measured by assessing the Agnor and Ki67 expression, in histopathological negative surgical margins of OSCC will be compared between with values of patient with recurrence.