1. Ferlay J, Shin HR, Bray F, Forman D, Mathers C, Parkin DM (2010) Estimates of worldwide burden of cancer in 2008: Globocan 2008. Int J Cancer 127(12):2893–2917
2. Howlader N (2011) Seer cancer statistics review, 1975–2008. http://seer.cancer.gov/csr/1975_2008/
3. Yu X (2011) Epidemiology of cancer recurrence, second primary cancer, and comorbidity among cancer survivors health services for cancer survivors. Springer, New York, pp 277–297
4. Shah I, Sefvan O, Luqman U, Ibrahim W, Mehmood S, Alamgir W (2010) Clinical stage of oral cancer patients at the time of initial diagnosis. J Ayub Med Coll Abbottabad 22(3):61–63
5. Silverman S (2003) Oral cancer, vol 1. PMPH-USA, Raleigh