Abstract
Introduction: Head and neck malignancies are responsible for 30% of all cancers in India with a dramatic increase in numbers due to widespread tobacco consumption. This study aims to assess the epidemiological and histopathological spectrum of these tumors. Materials and Methods: A large retrospective review of 5469 biopsy-proven patients presenting between 2018 and 2022 with head and neck cancers was done. Tumors were analysed for distribution according to sites of presentations, gender, age and histopathological profiles. Results: With a male-to-female ratio of 4.2:1, men constituted 80.80% of the study population. Mean age of presentation in women was 53.5 years, whereas men presented at an earlier age of 47.2 years. Oral cavity was the commonest site involved (59.7% cases) followed by the oropharynx (23.8% cases). Buccal mucosa was the commonest subsite involved with 1112 cases followed by tongue lesions with 1088 cases. Larynx was responsible for 17.04% of cases. All subsites were more commonly affected in men with the highest Male: Female ratio of 8.29:1 seen in larynx. The lowest ratio of 1.02:1 was seen in lesions of the face and scalp. Squamous cell carcinoma (SCC) was the most common histopathological diagnosis encountered in 88.97% of cases followed by basal cell carcinoma which was seen in 2.10% lesions. Conclusion: Oral cavity lesions constitute the bulk of head and neck cancer presentations in India. The disease is more prevalent in men overall and men present at a younger age in comparison to women. SCC is the most prominent histopathology encountered in our study.
Keywords: Head and Neck tumors, Oncology, Epidemiology, Northern India, Cancer
Introduction
Cancer as a disease has over the years evolved to become a modern-day epidemic affecting not only the developed world but also the developing countries [1]. According to the GLOBOCON data, India in 2020 reported 13,24,413 new cancer cases and 8,51,678 Indians lost their lives to cancer. India currently ranks third, behind China and USA in terms of the number of cases reported [2]. With an ever-increasing population, increasing number of people addicted to various forms of tobacco and alcohol and growing physical inactivity, India will be faced with an enormous burden of providing oncological treatment facilities to a substantial number of patients. It is predicted that by 2040 there would be a 57.5% increase in cancer burden from 2020 with an expected 2.08 million new cases [2].
Malignancies arising from the mucosal surfaces of oral cavity, pharynx, larynx, paranasal sinuses, nasal cavity and those affecting the major and minor salivary glands are collectively called as Head and Neck (HN) malignancies [3].
The 7th most common group of malignancies worldwide, the HN tumors account for approximately 30% of all malignancies in India [4, 5]. The burden of this disease in India can be gauged by the GLOBOCON 2020 data according to which carcinomas of the lip and oral cavity which are subsites of HN and are the most common malignancies found in men in India, fourth most common malignancies in women. Overall, with 1,35,929 cases, lip and oral cavity cancers contribute to almost 10.3% of cancer burden in India and represent the second most commonly diagnosed group of malignancies behind carcinoma of the breast [2].
According to a previous study published from our region in 2014, HN cancers were the most common group of malignancies diagnosed being responsible for about 17.96% of all cases with oral cavity being the most commonly affected sub-site being responsible for 44% of the head and neck malignancies [6].
This retrospective analysis aims to determine the distribution of Head and Neck malignancies in terms of site and define the gender, age and pathological profile of such patients in the Jaipur region of Northern India.
Materials and Methods
The present retrospective observational study was conducted in the department of Surgical Oncology, Sawai Man Singh Medical College, Jaipur over a period of five years from 2018 to 2022. After obtaining clearance from institutional ethics committee of our hospital data of 6861 patients with biopsy confirmed HN malignancies (Oral cavity, oropharynx, nasopharynx, hypopharynx, larynx, nasal cavity, ear, face and scalp) was sourced from various registries maintained at Departments of Pathology in the Jaipur region, namely at SMS medical college, S.D.M. Hospital, Bhagwan Mahavir Cancer Hospital and Dr K C Joshi Diagnostic lab.
Of the 6861 patients presenting with head and neck malignancies, 1392 patients presented with cervical lymph node metastasis with a carcinoma of unknown origin and these patients were excluded from final analysis.
Inclusion Criteria
Data was analyzed in terms of clinical and pathological profiles of the patients like age, gender, site of head and neck involved and histopathology of the malignancy diagnosed.
Patients more than 18 years of age, belonging to either gender with a histopathological confirmed diagnosis of a head and neck malignancy were included in the study.
Exclusion Criteria
Patients presenting with a cervical neck node metastasis from a carcinoma of unknown primary, locally recurrent disease, metastatic disease or with pre malignant and benign pathologies were excluded.
Data was analyzed using SPSS Version 22.0 and it includes descriptive statistics for demographic data, expressed in percentage or Mean ± Standard Deviation, median.
Results
Our study population consisting of 5469 patients had 4419 males (80.80%) and 1050 females (19.71%). Male to female ration of our study population was 4.2:1(Table 1).
Table 1.
Age (in decades) and Gender wise distribution of the patients
| Age Range (years ) | Men | Women | Ratio |
|---|---|---|---|
| 20–30 | 88 | 12 | 7.3:1 |
| 30–40 | 332 | 28 | 11.8:1 |
| 40–50 | 1858 | 191 | 9.72:1 |
| 50–60 | 1528 | 564 | 2.70:1 |
| 60–70 | 568 | 230 | 2.46:1 |
| 70–80 | 45 | 25 | 1.8:1 |
| Total | 4419 (80.80%) | 1050 (19.71%) | 4.2:1 |
Patients presented over a wide age range with the youngest patient being 20 years of age and oldest being a 77-year-old gentleman. Average age was 47.64 years. Men presented at a slightly younger age with a mean age of presentation being 46.4 years, whereas women had a mean age of presentation of 53.5 years.
Oral cavity was the most commonly involved region contributing 2640 cases (59.7%) followed by oropharynx with 1052 cases (23.8%). Larynx contributed 753 cases forming 17.04% of the study population. Other subsites included hypopharynx, nasal cavity, parotid gland, submandibular gland malignancies, nasopharynx, maxilla and paranasal sinuses, face/ scalp and ear (Table 2).
Table 2.
Region wise distribution of malignancies
| Distribution according to site | Numbers |
|---|---|
| Oral Cavity | 2640 (59.7%) |
| Oropharynx | 1052(23.8%) |
| Larynx | 753 (17.04%) |
| Hypopharynx | 331 (6.05%) |
| Nasal Cavity | 134 (2.41%) |
| Parotid gland | 132 (2.41%) |
| Orbit | 123 (2.2%) |
| Lip | 74 (1.3%) |
| Submandibular gland | 55 ( 1.0%) |
| Nasopharynx | 50 (0.91%) |
| Maxilla and PNS | 44 (0.80%) |
| Face and Scalp | 46 (0.84%) |
| Ear | 35 (0.63%) |
| Total | 5469 (100%) |
Amongst oral cavity malignancies (2640 cases), buccal mucosa (BM) was most commonly affected with 1112 cases (42.12%), closely followed by oral tongue with 1088 cases (41.2%). Alveolus of the mandible/maxilla was involved in 212 cases (8.03%). Retro molar trigone (RMT) was involved in 134 cases and floor of mouth (FOM) was involved in 94 cases. Amongst oropharyngeal cases (1052 cases), bulk of malignancies were seen in the tonsils with 604 cases followed by base of tongue involvement in 238 cases and soft palate affliction seen in 211 cases.
Glottis was the most commonly involved subsite in larynx contributing 582 cases (77.2%) of the total 753 cases followed by supra-glottis involvement seen in 156 cases (20.71%). Sub glottis was involved in 15 cases (1.9%) (Table 3).
Table 3.
Distribution of malignancies in the three most commonly involved subsites
| Site | Subsite | Number | Percentage |
|---|---|---|---|
| Oral Cavity | 2640 | 59.7% | |
| Buccal mucosa | 1112 (42.12%) | ||
| Tongue | 1088 (41.2%) | ||
| Alveolus | 212 (8.03%) | ||
| RMT | 134 | ||
| FOM | 94 | ||
| Oropharynx | 1052 | 23.8% | |
| Tonsils | 604 (57.41%) | ||
| Base of tongue | 238 (22.6%) | ||
| Soft palate | 211 (20.05) | ||
| Larynx | 753 | 17.04% | |
| Glottis | 582 (77.2%) | ||
| Supra-glottis | 156 (20.71%) | ||
| Sub-glottis | 15 (1.9%) | ||
| Total | 100% |
All sites and subsites in head and neck were more commonly involved in men as compared to women. Oral cavity lesions were seen in 2097 men (79.43%) and 543 women (20.56%), with a Male: Female ratio being 3.86:1. Highest disparities in gender affliction in oral cavity lesions were seen in lesions of the FOM with a ratio of 5.2:1 followed by RMT lesions with a ratio of 5.09:1. Least disparity was seen in tongue malignancies with a Male: Female ratio of 3.36:1.
Similarly in oropharynx, men were affected in 888 cases (84.41%) of the total 1052 cases and women were affected in 164 cases (15.58%), with a Male: Female ratio of 5.41:1. Highest disparity between genders was seen in carcinoma of the soft palate with a ratio of 8.13:1, tonsil malignancies had a ratio of 5.04:1 and least disparity was seen in malignancies of the base of tongue with a ratio of 4.80:1.
Laryngeal lesions (753 cases) were also predominantly seen in men with 672 cases (89.2%). Women contributed 81 cases (10.75%). Glottic tumors were the most common presentation of laryngeal malignancies and had a Male: Female ratio of a staggering 9.39:1. Supra-glottis tumors had a gender ratio of 6.8:1, whereas sub-glottis tumors were relatively evenly distributed with a ratio of only 2:1. Other sites which had a gender ratio ranging from 1.5:1 to 3:1 were the orbit, parotid, nasal cavity, nasopharynx, ear, Lip, maxilla and para nasal sinuses, and submandibular gland malignancies.
The only outlier in the group was malignancies of the face and scalp, with an almost equal gender affliction with a Male: Female ratio of 1.09:1 (Table 4).
Table 4.
– Gender wise distribution of malignancies in the sub sites
| Site | Men | Women | Ratio |
|---|---|---|---|
| Oral cavity (2640 cases) | 2097 | 543 | 3.86:1 |
| Oropharynx (1052 cases) | 888 | 164 | 5.41:1 |
| Larynx (753 cases) | 672 | 81 | 8.29:1 |
| Face and scalp (46 cases) | 24 | 22 | 1.09:1 |
Amongst the 5469 patients analysed, squamous cell carcinomas (SCC) were the most common diagnosed pathology with 4866 cases (88.97%). Amongst SCC, moderately differentiated variety was the commonest overall with 2596 cases (53.3%) followed closely by well differentiated variety with 2011 cases (41.32%).
Basal cell carcinoma (BCC) with 115 cases (2.10%) was the second most commonly diagnosed pathology in our study. But its distribution was relatively limited with bulk of cases being found in face and scalp and nasal vestibular regions.
Lymphomas had a relatively wider distribution with 94 cases (1.71%) and were the third most common histopathological variety. Major contribution being of the Non-Hodgkin’s variant with 73 cases (77.65%) of the total 94 diagnosed.
Affecting 89 patients (1.62%), mucoepidermoid carcinoma was the fourth most commonly diagnosed malignancy. Majority of the cases were detected in the parotid gland (64 cases, 71.91%). 10 cases were detected in the submandibular gland and the rest were spread over the palate, tongue, tonsils and buccal mucosa.
Verrucous carcinoma with 53 cases (0.96%) was the fifth most common malignancy found in the head and neck region.
Various other pathologies found were adenocarcinoma, Basi-squamous tumors, Acinic cell tumors, Adenoid cystic carcinomas, Neuroectodermal tumors, Carcinoid tumor, Ewings sarcoma, Leiomyosarcoma etc. Each of these contributed less than 0.1–0.2% of the cases and were not analysed separately (Table 5).
Table 5.
Histopathological spectrum of HN malignancies in our study
| Histopathological type | Numbers | percentage |
|---|---|---|
| Squamous cell carcinoma | 4866 | 88.97% |
| Basal cell carcinoma | 115 | 2.10% |
| Lymphomas | 94 | 1.71% |
| Muco-epidermoid carcinoma | 89 | 1.62% |
| Verrucous carcinoma | 53 | 0.96% |
| Rest | 252 | 4.6% |
| Total | 5469 | 100% |
Discussion
The head and neck region consists of a wide variety of delicately interlinked structures organized in a fashion vital for basic social and physiological functioning. The enormous economic and social burden this group of malignancies places on our healthcare infrastructure makes it imperative to detail the basic demographic and pathological profile of the disease in our population and understand it’s epidemiology.
Men were four times more commonly involved than women in our study with a Male: Female ratio of 4.2:1. Interestingly a pattern of increasing ratios can be noticed in studies from India with earlier Indian studies reporting ratios ranging from 1.5:1 to 2.1:1 [7–9]. Mehrotra et al. reported ratios of 3.8:1 in 2005 and Sharma et al. in a study from eastern Rajasthan reported a M:F ratio of 4.26:1 in 2012 [6, 10]. More contemporary studies including ones by Aggarwal et from Jaipur in 2015 described a ratio of 4.83:1 and Chauhan et al. from Patna in 2022 reported a staggering M:F ratio of 8.4:1 [11, 12]. All of these studies point towards a recent disproportionate increase in HN cancer incidence among men.
The most common age of presentation HN malignancies in our study population was the fifth decade of life with the mean age of presentation being 47.4 years. There was a difference in age of presentation in men and women with men most commonly presenting in the 5th decade of life followed by the 6th decade of life and women having maximum presentations in the 6th decade of life followed by the 7th decade, with mean age of presentation in men and women being 46.4 years and 53.5 years respectively.
While the present study reveals a slightly earlier age of presentation as compared to previous reports from our region and surrounding areas of India, most of the previous studies including the present study highlight that the 5th and 6th decades of life are the most common years of presentation of HN cancers in the Indian population [3, 6, 11]. While Sharma et al. from Jaipur in 2014 and Siddiquie et al. from Patna in 2012 described earlier presentations in women as compared to men [3, 6]. The present study and other contemporary studies from Bihar and Jammu regions of India have reported an alternative trend with an earlier age of presentation in men [12, 13].
This trend of increased prevalence of these cancers in the younger male population of our country could largely be attributed to the widespread consumption of tobacco by men in various forms including the widely prevalent smokeless forms like khaini and gutkha in our region. Chauhan et al. and Das et al. reported higher incidence of tobacco consumption in men in comparison to women [12, 14]. Another reason could be the belief among women in India of tobacco consumption being a social taboo [15]. Men, specially from poor and rural areas might have better access to healthcare services as compared to women and cases in women might be under reported. Kumar et al. in 2014 in their report on effect of tobacco addictions on upper aerodigestive tract malignancies concluded that tobacco consumption was more common in men, the less educated, the poor and rural sections of the society [16]. The global tobacco survey 2 carried out in 2016–2017 pointed out that although overall rates of tobacco consumption decreased from the first survey conducted in 2009–2010, still around 28.6% of the population above the age of 15 years (26.7 crore people) consumes tobacco in one form or the other. It also concluded that 29.6% of men and only 12.8% of women consumed smokeless tobacco in India [17].
Accounting for 59.7% of all malignancies in the present study, oral cavity was the predominantly affected site followed by oropharynx coming in as a distant second with 23.08% cases and laryngeal tumors constituting only17.04% of the cases. Similar trends were observed in previous studies from our region which reported oral cavity as the site with the maximum burden of cases in our population followed by oropharynx [6, 11, 12].
This was contradicted by reports from various regions of India. Siddiquie et al. and Rekha et al. reported a higher prevalence of laryngeal tumors [3, 18]. Studies from North Eastern India reported oropharynx as the most common site affected in HN malignancies [19, 20].
Gupta et al. from Jammu reported a sizeable and almost equal incidence of oral cavity and oropharyngeal tumors in their patients (32% each) [13]. These regional differences can be explained by different preferences for methods of tobacco consumption in different areas. Oral cavity lesions are more common where smokeless forms like ghutka, khaini are consumed and lesions of the pharynx and larynx are more common in patients who are addicted to consuming tobacco in the form of cigarettes and bidis (local Indian cigarettes without a filter) [21, 22].
The variations in tobacco chewing habit might also predispose to the subsite of oral cavity predominantly involved. A host of studies have reported the BM as the commonest subsite involved amongst oral cavity lesions [13, 23]. In our study, although BM was the commonest subsite involved with 42.12% cases, cancers of the tongue came in a close second with 41.2% of the total cases. There is wide discrepancy in the data reported on the most common subsite of oral cavity involved. From the Jaipur region itself, while Sharma et al. reported BM to be the most commonly involved region, Agarwal et al. clearly described the oral tongue as being the more commonly involved [6, 11]. Amongst oropharyngeal lesions, the present study and other regional studies have described tonsils as the most common subsite involved. But the study from Jammu pointed towards base of tongue being the more commonly involved subsite [13].
The squamous epithelium lines majority of the structures in the upper aero-digestive tract from which these malignancies originate. Similar to reports from our region and other centres in India, SCC was the most common histopathological diagnosis encountered in our study with 88.97% patients being affected [3, 6, 12]. Many studies from within and outside of India, including our study reported a higher overall incidence of the moderately differentiated variant (53.3% cases) followed by the well differentiated variety (41.3%) [24, 25]. Gowthami et al. from Bangalore in 2020 reported a higher incidence of the well differentiated variant [26]. Moderately differentiated variant was more common across both genders in our study, but Mehrotra et al. described the well differentiated variant to be more common in women and moderately differentiated variant to be more common in men [10].
Another trend which was reported by Cariati et al. was that of a higher prevalence of well differentiated tumors in patients younger than 40 years [24]. The present study could not demonstrate any such trend. Further research is needed to identify other factors and implications of tumor differentiation on presentation and prognosis in patients with these malignancies.
Oral cancers followed by oropharyngeal cancers constitute the bulk of the head and neck cancers affecting the northern regions of India. Cancers of the BM and oral tongue have an almost equal incidence of presentation. Squamous cell carcinoma is the most commonly diagnosed histopathological entity overall with basal cell carcinomas restricted mainly to regions of the face and scalp and nasal vestibule. These malignancies are four times more prevalent in men as compared to women. There has been a trend towards earlier presentation of these tumors in men as compared to women and men also seem to be getting diagnosed at an earlier age relative to reports from studies conducted previously. Thus, there is a need for social interventions and tobacco curtailment programs to prevent young Indians from getting addicted to tobacco at a younger age and subsequently decrease the incidence of this preventable disease.
Declarations
Institutional ethics committee approval
Taken.
Financial disclosures
None.
Conflict of Interest
The authors report the non-existence of any kind of conflict of interests.”
Footnotes
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