Reduction in tongue space/tongue volume ratio as a risk factor for oral tongue squamous cell carcinoma-an exploratory study.

BACKGROUND

The occurrence of tongue cancers in young adults with no associated habitual risk factors is emerging as a major health concern. The objective of the study was to investigate the role of low tongue space-tongue volume ratio as a risk factor for oral tongue squamous cell carcinoma.

METHODS

A case control study was conducted among histopathologically confirmed cases of squamous cell carcinoma of lateral border of the tongue who underwent treatment at the Department of Head & Neck Surgery (case group, n = 50). The patients with normal tongue referred for the evaluation of Magnetic Resonance Imaging of head region for other ailments formed the control group (n = 50). The space available for the tongue and the tongue volume of the study population were measured from the Magnetic Resonance Images (MRI), using in built software, and the mean Tongue space/Tongue volume ratio (TS/TV) of both the case group and the control group were calculated. A comparison of the TS/TV ratio was made between the test group and the control group using independent two sample -test. The cut off value for TS/TV ratio between the groups was determined using Receiver Operating Characteristic (ROC) Curve method and Odds ratio was calculated by grouping the study population as low or high TS/TV ratio group using the cut off value obtained.

RESULTS

A statistically significant variation was observed in the TS/TV ratio between tongue cancer patients and the normal controls with the mean value in normal controls higher than tongue cancer patients (p value = 0.009). The cut off value for TS/TV ratio for the development of tongue cancer was determined as 1.259 using ROC curve and the Odds ratio for malignant transformation in patients with low TS-TV ratio was calculated as 2.6.

CONCLUSION

A significant difference in TS/TV ratio between cases & normal controls observed in our study indicated that a lack of available space for the tongue either due to increase in tongue volume or decrease in tongue space may predispose an individual for the development of tongue cancer.