An epidemiologic assessment of cancer risk in oral precancerous lesions in India with special reference to nodular leukoplakia

Abstract

A cohort of 12,212 tobacco users was followed up annually to assess malignant potential of oral precancerous lesions in the Ernakulam district in Kerala, India. A total of 19 new oral cancers were diagnosed over a period of 8 years, and 15 (79%) of these arose from some preexisting precancerous lesion or condition. Nodular leukoplakia showed highest rate of malignant transformation (16% per year) as six of 13 nodular leukoplakia underwent malignant transformation over a mean follow-up period of 2.8 years. The relative risk (3243.2) compared with individuals with tobacco habits but without any precancerous oral lesion was also the highest for nodular leukoplakia. In addition, nodular leukoplakia was associated with submucous fibrosis in two patients, which progressed to oral cancer and was the clinical diagnosis for four lesions that turned out to be malignant on histopathologic examination. Nodular appearance was noted in two other precursor lesions as well. Thus, 14 of 19 oral cancers (74%) were either preceded by nodular leukoplakia and with lesions showing a distinct nodular appearance, or had the clinical appearance of nodular leukoplakia.

Prevalence and Correlation of Oral Lesions among Tobacco Smokers, Tobacco Chewers, Areca Nut and Alcohol Users

“…It is characterized by the presence of wavy white lines that radiate from a central erythematous area and occurs at the site of betel quid placement (Avon, 2004). All the lesions were diagnosed in accordance with international recommendations (World Health Organization, 1977;Axell et al, 1984;Gupta et al, 1989;Mehta et al, 1993;Zain et al, 1996;Rajalalitha et al, 2005).…”

“…The concept of certain precancerous lesions proceeding into oral cancer has long been accepted (Gupta et al, 1989;Yen et al, 2007). According to a workshop co-ordinated by WHO in May 2005 at London the use of the term 'Potentially malignant disorders' was recommended.…”

Oral Potentially Malignant Disorders among Dental Patients: a Pilot Study in Jordan

“…Unfortunately, the natural history of oral SCC is not fully understood (Napier and Speight, 2008;Scully & Bagan 2009), but current knowledge suggests that oral SCC develops in a stepwise process characterised by the initial presence of precursor cells and possibly lesions that subsequently (Reibel, 2003;Braakhuis et al, 2004;Angadi et al, 2012). Several studies have shown that many oral SCCs are preceded by identifiable precursor lesions or conditions (Gupta et al, 1998;Schepman et al, 1999;Warnakulasuriya et al, 2007). The term "oral potentially malignant disorders" (OPMD) was adopted by the World Health Organisation (WHO) in 2005 to describe oral lesions and conditions associated with a risk of malignant transformation (van der Waal, 2009).…”

Sources of variability in dietary intake in two distinct regions of rural India: implications for nutrition study design and interpretation

“…These villages were in the broad study area of a large-scale epidemiologic study of oral cancer, as described elsewhere (Gupta et al, 1989). Speci®c factors that are of interest include: day-of-the-week effects; sequence (ie the placement in the series of 24 h diet recall interviews from which the nutritional data were derived); season; region (for the combined analysis only); subject (ie inter-person) variability; and residual (ie intra-person) variability.…”