Measurement Variations Between Computed Tomography Derived Depth of Invasion and Histological Depth of Invasion in Oral Squamous Cell Carcinoma

Background: In treatment planning of oral squamous cell carcinoma the extent of local growth, regional and distant spread which is evaluated by tumor node metastasis (TNM) classification is needed. Clinically found depth of invasion from computed tomography may vary from histopathological depth of invasion. Accurate clinical measurement is essential for preoperative patient counseling, treatment planning and prognosis. So, it is essential to find out between two variations of depth of invasion in oral squamous cell carcinoma.

Objective: To determine variations in computed tomography derived depth of invasion with histopathological depth of invasion in oral squamous cell carcinoma.

Method: Twenty-four patients who fulfilled the criteria of the study were selected by purposive sampling. Cross sectional study had done.

Results: Most (37.5%) of the patients were aged ≥60 years followed by 29.2% were aged between 50 to 59 years, 16.7% were 40 to 49 years and 16.7% were 30 to 39 years of age. Among all the patients, 66.7% were female and 33.33% were male. Buccal mucosa (75%) was commonest site of cancer. Among the patients, exophytic growth was found in 70.8% cases followed by 16.7% was endophytic growth and 12.5% was ulcerative growth. Majority (70.8%) had Depth of invasion of cancer was above 10 mm followed by 20.8% had 5 to 10 mm and 8.3% had below 5mm both radiologically and histopathological assessment. CT scan derived DOI has a significant, positive and strong correlation coefficient with the histopathological DOI. CT derived DOI was higher in exophytic growth of tumor and lower in endophytic and ulcerative type of growth than histological DOI and that was also statistically significant.

Conclusion: CT scan can be a good guide to assess preoperative depth of invasion as a part of TNM staging.

Keywords: Oral Squamous Cell Carcinoma (OSCC), Depth of Invasion (DOI), Computed Tomography (CT), Radiological vs Histological DOI.