Background: The excessive consumption of tobacco in Southeast Asia especially in India has prompted us to undertake this retrospective study. Aims and Objective: The aim was to assess the prevalence of head and neck (HN) and oral cancer (OC) in Rajasthan State, India. Methods: A retrospective study on the prevalence of various cancers in the HN and oral cavity regions was conducted in the Department of Oncology, S.M.S Hospital, Jaipur, from 1 ^st August 2013 to 31 ^st July 2014. Results: A total of 4587 total body malignancy cases were reported for the out-patient department records, among which HN and OC constituted 1476 cases (32.18%). There were 640 (43.36%) and 836 (56.64%) HN, and OC cases, respectively. Conclusions: This study attempts to quantify and analyze the spectrum of HN and OC in the region. A comprehensive effort is needed to identify the cause of such high prevalence, generate awareness, adopting preventive measures and treatment modalities suited to meet this challenge.

INTRODUCTION

In the present-day scenario, the world is heading toward modern-day epidemics. Number of deaths reported due to cancer are not just limited to developing countries but even reached high prevalence among developed countries. [1] Among various cancers, head and neck (HN) cancer in India is emerging as a major public health problem. HN cancer is described as the cancer of the tonsil, pharynx, nasal cavity, salivary gland, hypopharynx and larynx. Oral cancer (OC) refers to the cancer of the lip, tongue, gingivae, floor of the mouth, palate (hard and soft), maxilla and cheek. [2],[3] The prevalence of HN cancer with respect to total body malignancy (TBM) varies from 9.8% to 40%. Its frequency is high in Asia and other less developed countries, and these countries account for nearly 0.7% million new HN cancer cases every year. In India, HN cancer accounts for 20-40% of TBM with oral malignancy (9.4%) observed as the most common site by Indian cancer registries. [4] OC is the sixth most common cause of death in males and seventh in case of females. [5]

Head and neck and OC are strongly associated with certain environmental and lifestyle risk factors, such as tobacco use, alcohol consumption, poor nutrition and ultraviolet light exposure. [4] Tobacco is consumed in various forms, although smoking and smokeless tobacco are the most common among them and one of the most common causes of OC. According to the World Health Organization, cancer has been growing at the rate of 11% annually in India due to widespread tobacco consumption. [1] Sankaranarayanan et al. [6] reported a significant increased risk of cancers of the tongue and the floor of the mouth in association with tobacco chewing, bidi smoking, combined bidi and cigarette smoking and alcohol consumption.

Other important risk factors such as viruses′ that is, human papillomavirus (HPV) and Epstein-Barr virus are adjuvant carcinogens, which act as distinct promotion factors. There could be a possibility of high infection of HPV among this population especially on the stain and abraded oropharynx mucosa as the result of the constant habit of smokeless tobacco mixed with lime against the back ground of poor oral hygiene on an individual who also takes tobacco and alcohol. [7],[8],[9] Recent evidence suggests that HPV may be linked with some oropharyngeal and OC cases. HPV-16 has been detected in up to 22%, and HPV-18 has been found in up to 14% of OC cases. [10]

An alarming increase in the prevalence of the HN and OC in Southeast Asia, especially in India has prompted us to undertake this retrospective study. This study, therefore, attempts to estimate the prevalence of HN and OC in this region which would help the health professionals to understand the burden and to implement strategies for control and prevention of this over spreading disease.

METHODS

A retrospective study on the prevalence of HN and OC was conducted in the Department of Oncology, S.M.S Medical Hospital, Jaipur. All the cancer patients registered between 1 st August 2013 and 31 st July 2014 were considered for the study. Jaipur with the sobriquet "Pink city" is the capital of Rajasthan state situated in the Northwest part of India. Being a tertiary hospital, patients from all the districts of Rajasthan state are being referred to this center, thus the hospital receives a fairly representative sample of cases across the state. For the analysis of data in the present study, Rajasthan state was divided into 6 zones, viz., north, south, center, west, east and others [Table 1]. The ethical clearance for the study was obtained from the Ethical Committee of Surendera Dental College and Research Institute before commencing the study and prior permission to conduct the study was taken from the Department of Oncology, S.M.S Medical Hospital, Jaipur.{Table 1}

A total of 4587 TBM cases were obtained from the out-patient department (OPD) registered during the time period (1 st August 2013-31 st July 2014) among which HN and OC constituted 1705 cases. Patients diagnosed in OPD and confirmed by histopathological evaluation, that is, 1476 were included in the study. Data was analyzed using IBM SPSS. Statistics Windows, Version 20.0. (Armonk, NY: IBM Corp). The statistical significant difference among groups was determined by the Chi-square test, and the level of significance was set at P < 0.05.

RESULTS

A total of 4587 TBM cases were reported at the OPD, among which HN and OC comprised 1476 cases (32.18%). There were 1223 (83.75%) male patients and 253 (16.25%) female patients in the study group. There were 640 (43.36%) and 836 (56.64%) HN, and OC cases, respectively. The most prevalent age group for OC was <40 years whereas for HN cancer it was 50-59 years, accounting for 26.56% and 32.19% cases, respectively. The prevalence of HN and OC was found to be least in the ≥70 years cases with 8.75% and 6.34% cases, respectively. There was a statistically significant difference between the prevalence of HN and OC with age, whereas no such difference was reported for gender [Table 2].{Table 2}

Tonsil was the most prevalent cancer site constituting 404 cases (27.37%), followed by the tongue with 284 cases (19.24%). The least common site was gingiva with 15 cases (1.02%). The highest reported cancer patients belonged to 50-59 years of age group while the least reported prevalent age group was ≥70 years comprising of 405 (27.44%) and 109 (7.38%) cases, respectively [Table 3].{Table 3}

While analyzing the prevalence of HN and OC, in relation to the zone, it was found that HN and OC were most prevalent in the west zone (24.69%) and central zone (31.82%) of Rajasthan state. HN and OC cases were found least in the east zone comprising of 7.03% and 3.83% cases, respectively [Table 4]. There was a statistically significant difference between HN and OC when tested in relation to zone from where case belongs (P < 0.05).{Table 4}

Altered taste was the most common symptom observed in both OC (30.14%) and HN cancer (29.69%). The least common symptom observed in HN and OC cases was dysphagia that is, 10.63% and 11.72% respectively [Table 5].{Table 5}

[Table 6] presents the prevalence of various deleterious habits such as smoking, smokeless tobacco, alcohol consumption and their combination with each other among cases with HN and OC. The most common habit was the combination of all three, that is, smoking, smokeless tobacco and alcohol, both in HN (26.09%) and OC (23.68%) cases, followed by smoking. Among the OC cases, 15.43% consumes smokeless tobacco, which is high as compared to HN cancer cases 10.16%. There was a statistically significant difference between HN and OC with smokeless tobacco (P < 0.05). Alcohol consumption was greater among HN cancer cases (15.47%) when compared with OC cases (10.65%). Smoking along with smokeless tobacco consumption was higher in OC cases (12.68%) while in HN cancer cases it was found to be only 4.38%. There was a statistically significant difference between HN and OC with alcohol consumption as well as smoking along with smokeless tobacco (P < 0.05).{Table 6}

In multivariate analysis HN and OC cases showed highly significant association (P < 0.0001) with smoking, smokeless tobacco, alcohol consumption and the combination of all three, that is, smoking, smokeless tobacco and alcohol [Table 7].{Table 7}

DISCUSSION

The overall prevalence of HN and OC cases reported in the present study is 32.18%, which is toward the higher end according to the range of 10%-40% being reported by other studies. [11],[12],[13],[14],[15] A higher prevalence of the disease in India (54.48%) was reported by Bhattacharjee et al. in the northeastern states. It has been indicated that several factors predispose to HN and OC. The use of tobacco, lime, betel and smoking are very common oral habit prevalent in this region, which might be one of the major causes. [5]

Oropharynx has been reported as the most prevalent HN cancer type by various studies, [5],[16] but on the contrary, the results of the present study showed no such trend and it accounted for only 4.67% of the cases, which is similar to the findings of the study conducted by Shinde and Hashmi [17] in which oropharynx constituted only 3.66% of the TBM. According to various studies, [7],[8],[9],[10] the reason for such a high trend could be that fewer patients had reported with HPV since research had proven a correlation between HPV and oropharyngeal cancer. In the present study tonsil (27.37%) was the most common site for HN cancer, which was similar to the findings reported by Shiboski et al.[18] (30.01%) but in disagreement with the results of the study conducted by Sharma et al., [19] where tonsil constituted only 4.2% of the HN cancer cases.

Hypopharynx accounted for 3.86% of the cases in the present study, which was similar to the results of the study carried out by Shunyu and Syiemlieh et al. (2.31%). [4] However, in other studies, [20],[21],[22],[23] it accounted for 11.7%-28.3% of the cases. Laryngeal cancer comprised 7.45% of the total cases which was somewhat similar to the results in the study conducted by Shiboski et al. (5%) [18] while in relation to other research [21],[22],[24] it ranged from 11% to 26% of the total cases.

Earlier studies [11],[21],[22],[25] had shown that OC accounted for 24%-28% of the cases whereas in the present study OC accounted for 56.64% of the cases, which was somewhat similar to the findings of the study carried out by Shinde and Hashmi [17] which reported 41.28% of the cases. The tongue was the most affected oral site as seen in other studies. [5],[14],[17] However, in the studies conducted by Shunyu and Syiemlieh et al.[4] and Bhurgri et al.[26] the pattern was not the same. In agreement with the present study, cheek was the second most common oral site of OC in various studies [4],[17] and in dissimilarity with the findings of the study conducted by Bhurgri et al., [26] this difference could be due to the high consumption of smokeless tobacco.

Various studies [5],[21],[22] have shown that the most common age group for occurrence of cases was the sixth decade comprising 30-40% of the overall cases, whereas in the present study the fifth decade was the commonest age group, which comprised of 405 cases (27.44%) which was similar to the findings of the study conducted in Pakistan by Bhurgri et al.[26] In the current study, the most prevalent age group for OC was <40 years whereas for HN cancer it was 50-59 years. When the gender distribution was calculated it was found that, male to female ratio was 4.83:1 which was somewhat in the range of the findings of the study conducted by Bhattacharjee et al.[5] (3:1), while in other studies this ratio was 1.5:1-2.1:1. [20],[21],[22],[24]

Santos et al.[27] in their study stated that pain was the most prevalent general symptom affecting 71.5% of the patients while in the present study altered taste was the most prevalent general symptom affecting 29.95% of the patients, followed by pain (27.17%).

The limitations of the present study was that the information was collected retrospectively, thus being subject to inherent inaccuracies, including the inability to control bias and cofounders, although the sample size generated in the present study could have not been generated by any other study design. The authors believe that few more sociodemographic factors could have been added, but due to the retrospective design there was a limited access.

CONCLUSIONS

The rising prevalence of HN and OC cases in the Rajasthan state is alarming. While HN and OC cases are difficult to manage, they are, however, very much preventable, and the emphasis, therefore, ought to be on preventing the onset and early diagnosis. It is pertinent to note that when the symptoms become noticeable to patients, they are already an indication of an abnormality, foreshadowing advanced disease, suggesting rapid evolution of early disease stage to more advanced stages. Over and above, lack of awareness about cancer has made the scenario even worse. This study quantifies and analyses the spectrum of the prevalence of HN and OC in the region. A comprehensive effort is needed to identify the cause of increasing prevalence, generate awareness, adopting preventive measures and treatment modalities suited to meet this challenge.