Determination of Pathoradiological Association between Depth of Invasion and Neck Node Metastasis in Oral Cavity Tumours

Study Background: Depth of invasion, although being considered as an independent risk factor for occult lymph node metastasis in oral cavity cancers, is very difficult to obtain by frozen section or incisional biopsy, making neck dissection compulsory for its’ determination. Hence, in this study, we are trying to set a pre-operative radiological cut-off through which we can prevent or limit un-necessary neck dissections and thus, reduce the associated co-morbidities. Aims: 1) To know whether the increase in the depth of invasion in oral cavity carcinoma assessed histopathologically and radiologically co-relates with neck node metastasis. 2) To accurately co-relate the radiological thickness at which neck dissection is required. Methodology: A retrospective study has been conducted over thirty patients with oral cavity carcinoma (buccal mucosa and anterior two-thirds of the tongue) in the time period of April 2018 to December 2018 who were operated in our tertiary care hospital. Results: Depth of invasion is relatable histopathologically and radiologically and is directly proportional to neck node metastasis. Pre-operative radiology is a reliable modality to rule out the need of neck node dissection. Conclusions: Depth of invasion is directly proportional to the incidence of neck node metastasis and pre-operative radiology has been reliable to rule out the need of neck dissection and reduce its morbidity.