Significance of promoter hypermethylation of p16 gene for margin assessment in carcinoma tongue.
BACKGROUND
Loss of p16 expression by promoter hypermethylation has been reported as an early event in the development of oral cancer. The aim of our study was to explore the prognostic implications of presence of promoter hypermethylation of p16 gene in surgical margins in carcinoma tongue.


METHODS
A prospective analysis of 38 patients with resectable carcinoma tongue was carried out. DNA from tumor and the surgical margins was assessed by methylation-specific polymerase chain reaction. Follow-up duration was 17 to 37 months.


RESULTS
About 86.8% of tumors showed promoter hypermethylation of p16 gene. Out of 30 patients with histologically free margins, 43.3% showed positivity on molecular assessment. Patients with positive molecular margins had a 6.3-fold increased risk of having local recurrence as compared to patients with negative margins.


CONCLUSIONS
Promoter hypermethylation of p16 gene may serve as a useful molecular marker for predicting local recurrence in carcinoma tongue.
Department of Otorhinolaryngology-Head and Neck Surgery, All India Institute of Medical Sciences, New Delhi.
Parul
P
Sinha
S
S
Bahadur
Alok
A
Thakar
Ajay
A
Matta
Muzafar
M
Macha
Ranju
R
Ralhan
S Datta
SD
Gupta
D000328:Adult; D000368:Aged; D002294:Carcinoma, Squamous Cell / Q000235:genetics* / Q000473:pathology / Q000601:surgery; D015331:Cohort Studies; D019175:DNA Methylation / Q000502:physiology*; D018572:Disease-Free Survival; D005260:Female; D019942:Genes, p16 / Q000502:physiology*; D005819:Genetic Markers / Q000235:genetics; D005927:Glossectomy; D006801:Humans; D008297:Male; D008875:Middle Aged; D009364:Neoplasm Recurrence, Local / Q000235:genetics* / Q000473:pathology; D011237:Predictive Value of Tests; D011401:Promoter Regions, Genetic / Q000502:physiology*; D014062:Tongue Neoplasms / Q000235:genetics* / Q000473:pathology / Q000601:surgery; D016896:Treatment Outcome
D005819:Genetic Markers