Oral Cancer - An Overview

Abstract

Neoplasms of diverse cellular origin arise in the oral cavity and among these oral squamous cell carcinoma (OSCC) arising from the mucosa of the oral cavity constitutes to over 90% 1, 2. Oral cancer encompasses all the malignancies originating in the oral tissues, including cancers of the lip, tongue, gingiva, floor of the mouth, buccal mucosa, palate and the retromolar trigone. It is the 6 th most common cancer worldwide 3. Oral squamous cell carcinoma is described as an invasive epithelial neoplasm with varying degrees of squamous differentiation and a propensity to early and extensive lymph node metastases, occurring predominantly in alcohol and tobacco using adults generally in the 5 th and 6 th decades of life. Globally about 5, 00,000 new cases of oral and oropharyngeal cancers are diagnosed and three quarters of these are from the developing world 7, 8, 9. Approximately 3, 89,650 cases occurred in the year 2000 out of which 2, 66,672 were in the oral cavity (ICD-9 140-5) and 1, 22,978 for the cancer of oropharynx (ICD-9 146, 8-9). This represented about 5% of all cancers for men and 2% for women 10. Oral and oropharyngeal cancers remain one of the more common cancers in the South and South East Asian countries, as opposed to Western society, where it accounts for only about 1-4% of the of reported cancers incidence 4. For example, the incidence of oral cancer in India is high, constituting about 12% of all cancer in men and 8% in women 5 ; mortality rate is equally high in this population, ranking number one in men and number three in women 6. Oral and oropharyngeal cancers therefore qualify as major public health problem, not only in India, but also globally. Worldwide, oral cancer incidence rates appear to have been stabilizing over the last decade 12 , but the greater frequency of oral cancer in certain regions and among specific populations is a cause for concern since their overall 5-year survival rate is 53% and it has not changed in the last two decades 13. With this heightened awareness, research to further investigate the detection, diagnosis and prevention or oral cancer has recently been included as one of the targeted priorities supported by the National Institute of Dental and Craniofacial Research (NIDR) in the United States 14. The overall 5-year survival rate for patients without clinically evident cervical lymph node metastases is 85%. However, patients with microscopic lymph node metastases have a survival rate of 54%. It has been estimated that 20-50% of patients without clinically evident cervical lymph node metastases do in fact have microscopic metastases and therefore poorer www.intechopen.com Oral Cancer 48 prognosis 87. Among the Indian population, the overall 5-year observed and relative survival rates were 30.5% and 39.7%, respectively. Survival steadily declined with advancing age and advanced clinical stages. 5-year observed survival was 59.1% for localized cancer, 15.7% for cancers with regional extension and 1.6% for those with distant metastasis. Those with tongue, buccal mu...

Expression of mucin-1 in oral squamous cell carcinoma and normal oral mucosa: An immunohistochemical study

“…Despite the advances in therapeutic approaches, percentage of morbidity and mortality of OSCC patients has not improved significantly during the past 30 years. [ 1 12 ]…”

“…Neoplasms of diverse cellular origin usually arise in the oral cavity, and among these, the oral squamous cell carcinoma (OSCC) and its variants constitute over 90% of the oral malignancies. [ 1 ] Globally, overall, oral cancer has been reported as the 15 th most common (male and female) and 11 th most common cancer in men. [ 2 ] However, there is a significant difference in the incidence of oral cancer in different regions of the world, with the age-adjusted rates varying from over 20/100,000 population in India to 10/100,000 in the USA and <2/100,000 in the Middle East.…”

Evaluation of Serum C-Reactive Protein Levels in Oral Premalignancies and Malignancies: A Comparative Study

“…According to Radhakrishnan et al [10], oral malignancies occur predominantly in adults, generally in the 5th and 6th decades of life, due to the higher prevalence of risk factors such as tobacco and alcohol.…”

Nitrite detection using plastic optical fiber (POF); an early stage investigation towards the development of oral cancer sensor using POF

“…Some of the risk factors identified are tobacco smoking, alcohol consumption, viruses, dieting habit and deficiency states [5]. Despite numerous advancement in treatment, the five-year survival rate for the oral cancer patients is still 50% for the past few decades, mainly due to lack early stage diagnosis, with 60% of the patients are examined to have oral cancer when the disease is at stage III and IV [1,6,7].…”