A prospective study to evaluate the impact and independency of depth of invasion in comparison with other clinicopathologic prognostic variables in oral cavity malignancy

Abstract

Background: Depth of invasion is included in the staging of oral cavity malignancies in the recent 8 th edition of American Joint Committee on Cancer or tumour, node and metastasis staging system. This study analyses the impact of diffuse optical imaging (DOI) on incidence of lymph node involvement, stage migration, postoperative margin and independency. Methods: Postoperative HPE of fifty patients with oral cavity malignancy operated in our institute from January 2018 were collected. Depth of invasion and other pathological parameters were documented. DOI divided into three groups and statistical analysis done. Results: No lymph node metastasis is found in superficial tumours, 43% of intermediate thickness and 76% of deep tumours had lymph node involvement. Positive margin is seen only in patients with tumour DOI more than 0.5 cm, more than 50% of deep tumours had close margins while 75% of superficial tumours had adequate margin. Out of the 24 T3 tumours in this study 13 were upstaged due to inclusion of DOI, which would have been T2 according to the previous staging system. There is 54.1% (13 out of 24) upstaging in T3 tumours (T2 to T3), 23% (3 out of 13) in T2 (T1 to T2). There is no significant correlation between DOI and anatomical site, tumour size, tumour thickness, lymphovascular invasion and grade. Conclusions: Depth of invasion in oral cavity malignancies impacts adversely lymph node metastasis and margin status. It is an independent prognostic factor in oral cavity malignancy.

Depth of Invasion as an Independent Predictor of Survival in Patients of Stage III Squamous Cell Carcinoma of the Oral Tongue

“…Few smaller studies have shown DOI as an independent predictor for survival in T3 OSCC. 5,6 When AJCC stage III OTSCC is considered where more variables are present (node positivity), heterogeneity increases, and therefore more sub-groups may have different survival. The study aims at establishing DOI as an independent predictor across different sub-groups of AJCC stage III OTSCC.…”

“…The difference in prognosis between these sub‐groups is yet to be determined. Few smaller studies have shown DOI as an independent predictor for survival in T3 OSCC 5,6 . When AJCC stage III OTSCC is considered where more variables are present (node positivity), heterogeneity increases, and therefore more sub‐groups may have different survival.…”