Head and neck cancers – Prevalence and risk factors in Andhra Pradesh state, India

A preliminary analysis

Abstract

Aim: 

The aim of this article is to study the prevalence of Head and Neck Cancers (HNC), risk factors, stage at diagnosis, site, and histopathology status in Andhra Pradesh from a hospital-based data and compared with the data available in other areas in the state.

Materials and Methods: 

A retrospective analysis is carried out from the hospital data collected from the records and clinical files from the years 2010 to 2018. Patient's geographical area, risk factors, staging, etc., are analysed. Staging is done based on T- tumour size, N – Lymph nodal status, M – metastases status (TNM) classification and group stage. The cancer site is classified based on International Classification of Disease (ICD) for oncology (ICD-02).

Results: 

2544 patients of HNC are found in this study. A significant male predominance is noticed. Majority of the patients belong to the 40–60 age group (P < 0.001). The risk factors or habits are smoking, alcohol, chewing or combination of these in both males and females (P < 0.001). In both the sexes all the risk factors are seen mainly in tongue, hypo pharynx, and buccal mucosa. And, buccal mucosa patients are associated mainly with chewing tobacco habit, with male predominance. Most of the early stage disease (Stages 1 and 2) are noticed in females, whereas late stages (Stages 3 and 4) are noticed in males. (p-value < 0.001).

Conclusion: 

Smoking, alcohol, and chewing are the common risk factors found among the patients. There is male predominance in the present study. Tongue and hypo pharynx cancers are associated with smoking and alcohol whereas chewing is found in buccal mucosa cancers.

INTRODUCTION

In India, head and neck cancers (HNC) are one third of all cancers, whereas in developed world where they contribute 4–5%.[¹] And it is the major cause of morbidity and mortality in the world. The incidence is high in India and Southeast Asia where the oral cancers consist up to 40% of all malignancies.[²] The risk factor profile for HNC consists mainly of smoking, alcohol, chewing tobacco, or combination of these. Poor oral hygiene and Human papillomavirus (HPV-P16) infection are also considered as risk factors for tongue, tonsil, and oropharyngeal HNC and in non-smoking cases of HNC.[³] The risk of HNC is increased by smoking of bidi, reverse smoking, chewing tobacco, beetle, quid, and areca nut.[⁴] Reverse smoking is observed in certain group of people in north costal Andhra Pradesh (AP).

The prevalence of cancer varies from one community to another and differs in different communities in same geographical location. Habits are different in different areas, for example, in central Andhra, drinking alcohol in females is uncommon but it is a custom and socially accepted habit in Telangana state.[²] Chewing beetle and quid is common in certain areas of Andhra and Rayalaseema areas.

There are many articles on risk factors in HNC in India. But there is less literature available regarding habits/risk factors profile of HNC in AP. When the state was a combined state, one study was carried out in Hyderabad with data from two major Institutions. Though there are some patients from Andhra area, majority of them are from Telangana area.[²] One more study is available from Rayalaseema area from an institute in Tirupati.[⁵] There is no specific information available from the central Andhra area in AP state. Any oncology institute or hospital serves as a referral hospital not only for that district and also for the neighbouring districts. As there are different habits, risk factors and stages at diagnosis, we report data from our hospital-based registry from 2010 to 2018 and tried to compare with data of other areas.

MATERIALS AND METHODS

This is a retrospective study carried out from a tertiary hospital-based cancer registry. This study is approved by the Ethics Committee of the hospital. Data are collected from the excel sheet for the years 2010 to 2018. Where there is incomplete information in excel sheets, patient files are verified. All histologically confirmed cases [either by biopsy or by Fine Needle Aspiration Cytology (FNAC)] are included in the study. The information collected are regarding the geographical distribution and patient information (like age, gender, risk factors, site of origin, histopathology, and stage at the time of presentation). The patient files having incomplete information are excluded from the study (n-112 of which males are 74 and females are 38). All the cases are staged using TNM classification and group staging. Stages are classified into early stage and late (locally advanced) stages. Stage 1 and 2 are considered as early stages whereas Stages 3 and 4 are considered as late stages. All the patients are studied are compared with different studies done in AP state.[²⁵]

Analysis: The data are analysed using Microsoft Excel. Chi-square test was performed to assess the association of gender with age groups, habits site, stage, and histopathology of cancer.

RESULTS

A total of 2544 HNC patients from 2010 to 2018 are identified in this study. A male predominance is noted in these patients. Male patients are 1693 (66.55%) and females are 851 (33.45%). Majority of patients are seen in the age group of 41–60 years accounting to 1167 (567 + 600) in both males and females. Median age for males is 55.5 yrs and for females, it is 45.5 yrs. It is noticed that lowest age is 3 yrs. and highest is 94 yrs. Highest number of 416 (24.57%) patients are seen in the age group 51–60 years in males, whereas 216 (25.38%) patients are seen in the age group 41–50 years) in females [Table 1]. P value < 0.0001.

Table 1: Distribution of age and gender

Geographical distribution: It is observed that the majority (62.93%) of the patients are from Krishna district of AP state. It is followed by surrounding districts like, West Godavari (8.49%), Guntur (7.07%), Prakasam (4.67%) districts of AP and Khammam (7.51%) district from Telangana state. A small number is noticed from other districts in south of AP like Anantapur (3.77%), Nellore (0.71%), Kurnool (0.16%), Kadapa (0.12%), and Chittoor (0.16%). Another small number is seen in districts from North costal AP like East Godavari (1.26%), Visakhapatnam (0.39%), Vijayanagram (0.59%), and Srikakulam (0.79%). Thirty-five (1.38%) patients are categorised as others which included people residing in other states like Telangana, Maharashtra, Rajasthan, Orissa, Karnataka, Tamil Nadu, etc., [Table 2].

Table 2: Geographical distribution. n=2544

Habits: The predominant risk factors identified are smoking, alcohol, and chewing of tobacco and its products like pan parag, certain types of pan, gutka, khaini, etc., The study also is carried out for smoking alone, alcohol alone, chewing alone, or combination of these groups. Smoking alone is found in 19.55% of males, followed by combinations of smoking + alcohol + chewing in 16.66% and smoking + alcohol in 14.83%. In females, 13.40% of patients are found to have chewing habit followed by smoking + alcohol + chewing in 6.23% and smoking alone in 5.76%. A total of 910 patients are found to have no habits of which 342 (20.20%) patients are males and 568 (66.75%) patients are females [Table 3] P < 0.001. Smoking and alcohol are predominantly found in cancers of tongue, base tongue, larynx, floor of mouth (FOM), alveolus, retromolar trigone etc., Whereas chewing quid, gutka, pan parag, khaini, etc., are mainly associated with cancers of buccal mucosa and to less extent in FOM patients.

Table 3: Distribution of habits in relation to gender (n=2544)

Sites: All are analysed for site-wise distribution. The common sites of cancers are tongue (n = 664, males (27.23%), females (23.85%)), hypo pharynx (n = 498, males (11.99%), females (34.67%)), and buccal mucosa (n = 299, males (12.70%), females (9.87%)). Highest number of patients are noted to have cancer tongue with male predominance (27.23%). Surprisingly hypo pharynx is found to have majority of patients in females (34.67%) whereas all other sites in females are very much less in number compared to males. Other sites having small number like alveolus, nasal cavity and paranasal sinus tumours, salivary gland, thyroid gland, retromolar trigone, tonsil, etc., are grouped in others category P < 0.0001 [Table 4].

Table 4: Incidence of cancer site and gender (n=2544)

Histopathology analysis indicates that squamous cell carcinoma (SCC) is the most common variety and accounts for highest number (2313), followed by adenosquamous, adenoid cystic, mucoepidermoid carcinoma, pleomorphic adenoma, etc., [Table 5] P < 0.0001.

Table 5: Distribution of histopathology in the study population (n=2544)

In the stage at diagnosis, the distribution of males is 19.96%, 24.98%, 31.67%, and 23.39%, for the stages 1, 2, 3, and 4, respectively. Similarly, for females, it is 36.31%, 32.67%, 24.21%, and 6.81%, respectively. Majority of female patients are seen in early stages (Stages 1 and 2) and males patients are seen in late stages (Stages 3 and 4). P value is <0.001) [Table 6].

Table 6: Distribution of stages with relation to gender. n=2544

DISCUSSION

This study is a hospital-based and retrospective study. It is focused on histologically confirmed cases (either by biopsy or by FNAC). A male predominance in the present study shows men habituated to more risk factors for HNC, like smoking, alcohol, chewing, or combination of these. Smoking is usually seen in the form of cigarette, bidi (country cigarette), and cigar (chutta). Smoking is seen in many patients either alone or in combination with alcohol or chewing. Many of the patients in oral cancers are seen in late stages due to prolonged exposure to the risk factors in both sexes.[²]

Alcohol is consumed in the form of either alcohol beverages (beer, brandy, whisky, etc.) or toddy and sara (locally made liquor). In this study, alcohol consumption is seen in majority of patients. Toddy is considered as socially and culturally accepted drink in certain areas in Telangana state.[²] Combined AP state consists of Telangana, Andhra, and Rayalaseema areas. In the year 2014, Telangana area has got a separate statehood. So, our study also consists of patients referred here for treatment from the neighbouring Telangana state districts like Khammam, Nalgonda, etc., This is the reason some of the habits from Telangana area are also seen in our study (e.g., drinking of alcohol among some of the females). Women drink toddy for relief of body aches to have a good sleep in the night and to make them prepared to work on the next day.[²⁶] Patients not having any habits in females is 66.75% and in males, it is 20.20%. In South India, majority of females do not have smoking or alcohol habits. Commonly, smoking, and alcohol habits are seen in males.[⁵]

Chewing tobacco and related products like pan, gutka, pan parag, khaini, quid, etc., are seen in both the states. Chewing is seen only in 7.8% of males whereas it is 13.40% in females. This may be due to females belong to lower socioeconomic group in certain areas in both the states, are habituated to pan, lime, betel nuts, etc., In females, chewing alone is followed by smoking + alcohol + chewing (6.23%) and smoking alone (5.76%). In reverse smoking, they smoke with the burning end of cigar (chutta) keeping inside the mouth and they enjoy the heat. That palate area is subjected to the maximum amount of heat. Experimental studies suggested that heat functions as a co-carcinogen and accelerates neoplastic changes.[⁷] This habit usually seen in females of rural areas of north coastal districts of AP state – Srikakulam, Vijayanagaram, Visakhapatnam, and East Godavari districts. This habit is prevalent among fishermen of rural AP, India. In their local language it is called “Adda Poga”. Reverse smoking is also seen in some areas of other countries like Philippines, South America, Caribbean, Netherlands, etc., In India, it is also seen in Orissa and Goa states. It is observed that they develop palatal lesions.[⁸] In this study, about 77 patients originally belong to above mentioned districts of AP state showing contribution of reverse smoking is also a risk factor in this study.

In males, the cancers are seen in advanced or late stages (Stage 3 and 4) showing 31.67% and 23.39% involvement, respectively. In females, cancers are seen in early stages (Stages 1 and 2) showing 36.31% and 32.67%, respectively. This may be because males are exposed to risk factors for prolonged periods and do not undergo examination due to busy in work or occupation. All the values are statistically significant. P value= <0.0001. As a preventive measure, high-risk patients require to undergo frequent screening tests or mouth self-examination as a cost-effective alternative.[¹]

In this study, high prevalence of cancer sites are seen in males in cancer tongue (27.23%) followed by larynx (14.65%) and buccal mucosa (12.70%). Surprisingly in female's hypo pharynx shows highest number (34.67%) followed by tongue (23.85%), and buccal mucosa (9.87%). Smoking and alcohol are the common risk factors noticed in tongue and larynx sites. Hypo pharynx consists of sub sites like pyriform fossa, posterior pharyngeal wall, and postcricoid. That might be the reason for the high number in hypo pharynx. These patients also have exposure to all other risk factors. But in buccal mucosa, chewing of tobacco and its products are noticed in majority of patients in both sexes. This may be due to prominent chewing habit and prolonged exposure of chewing materials like gutka, quid, etc.[⁹] Palatal carcinoma has 7.05% incidence in females and 4.67% in males. To certain extent this may be due to reverse smoking and other habits. All the values of the sites are statistically significant. P value= <0.0001. Histopathology study reveals highest number of patients have SCC (90.92%) compared to others like adenocarcinoma (1.10%), adenoid cystic carcinoma (0.79%), mucinous carcinoma (0.67%), and others (6.53%). P value= <0.0001.

In the study by L Addala et al.,[²] highlights taking data from two institutions in Hyderabad. Prevalence of cancer tongue is compared to our study (25.54% vs 26.10%) in both males and females together. Prevalence in buccal mucosa shows minor change (15.15% vs 11.75%) in both sexes. Prevalence of hypo pharynx shows high in our study (11.78% vs 19.57%). The reason for high incidence of number is discussed above.[²] In Rayalaseema, HNC counts for almost 15.9% in both sexes.[⁵] Cultural differences in the use of tobacco, toddy drinking, and reverse smoking habits show geographic variations and anatomic incidence of HNC.[²]

This study is a hospital-based one and it projects the risk factor profile of patients in these districts in AP. The data reflect a specific population, but not the whole community. State wise cancer registry (or Population-Based Cancer Registry) with a standard format is required to be started by the Government. This may help to understand the prevalence, risk factor details, geographical, and anatomical variations. There is a need to take preventive measures like anti-tobacco, educational programmes by media, and non-government organizations.

Financial support and sponsorship

Nil.

Conflicts of interest

There are no conflicts of interest.