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ORIGINAL ARTICLE
Year : 2018  |  Volume : 9  |  Issue : 3  |  Page : 114-118

Demographic and clinicopathological profile of oral squamous cell carcinoma patients of North India: A retrospective institutional study


1 Department of Oral Pathology and Microbiology, Sardar Patel Postgraduate Institute of Dental and Medical Sciences, Lucknow, Uttar Pradesh, India
2 Department of Oral and Maxillofacial Surgery, Sardar Patel Postgraduate Institute of Dental and Medical Sciences, Lucknow, Uttar Pradesh, India

Date of Web Publication27-Sep-2018

Correspondence Address:
Bharadwaj Bordoloi
Rajdhani Apartment 1, 2b Housefed, Dispur, Guwahati - 781 006, Assam
India
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Source of Support: None, Conflict of Interest: None


DOI: 10.4103/srmjrds.srmjrds_21_18

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  Abstract 

Background: Oral cancer is one of the ten most common cancers in the world. In India, it is the most common cancer among male and the third most common among female population. Objective: The aim of this study was to evaluate retrospectively the epidemiologic profile of patients with oral squamous cell carcinoma (OSCC). Method: The study sample comprised of ninety eight biopsies diagnosed as OSCC. The clinical and histopathological features were analyzed using descriptive statistics, Student's t test and chi-square test. Results: Male to female ratio was 3.26:1. Mean age was 51.35 ± 14.39 years and 55.35 ± 8.87 years in males and females, respectively. The most common site of occurrence was buccal mucosa and gingivo-buccal sulcus (GBS). Most of the cases (66.32%) were well-differentiated OSCC. In most of the cases (66.32%) the diagnosis was made within 2-6 months of onset of symptoms. Conclusion: In India, OSCC is a major health problem. Strategies must be made to improve the present scenario of health care service, where Government-run health care centers are burdened with ever-increasing patient pool and to avail treatment in such centers is always a compromise with time and health. Effective oral health programs for spread of knowledge and awareness, prevention, early diagnosis and management, and follow up of oral cancer must be implemented.

Keywords: Demographic, epidemiology, oral squamous cell carcinoma, retrospective


How to cite this article:
Tandon A, Bordoloi B, Jaiswal R, Srivastava A, Singh RB, Shafique U. Demographic and clinicopathological profile of oral squamous cell carcinoma patients of North India: A retrospective institutional study. SRM J Res Dent Sci 2018;9:114-8

How to cite this URL:
Tandon A, Bordoloi B, Jaiswal R, Srivastava A, Singh RB, Shafique U. Demographic and clinicopathological profile of oral squamous cell carcinoma patients of North India: A retrospective institutional study. SRM J Res Dent Sci [serial online] 2018 [cited 2023 Jun 3];9:114-8. Available from: https://www.srmjrds.in/text.asp?2018/9/3/114/242449


  Introduction Top


Oral cancer is one of the ten most common cancers in the world and grouped together with pharyngeal cancer, it is the sixth most common cancers in the world.[1] An estimated 378,500 new cases of intraoral cancer are diagnosed annually worldwide. In developed countries, oral cancer is less common but is the eighth most common form of cancer overall; however, the ranking varies a great deal among countries. For example, in areas of northern France, oral cancer is the most common form of cancer in men. The prevalence of intraoral cancer appears to be rising in many countries, especially in younger people.[2] The global incidence of lip, oral cavity, and pharyngeal cancers of 529,500, corresponding to 3.8% of all cancer cases, is predicted to rise by 62% to 856,000 cases by 2035 because of changes in demographics.[3]

Cancers of the oral cavity and hypopharynx are highly common in Asian countries.[3] One-third of global cases and one-half of oral cancer-related deaths are reported from Southeast Asia.[4] In certain countries, such as Sri Lanka, India, Pakistan, and Bangladesh, oral cancer is the most common cancer.[2] In parts of India, oral cancer can represent more than 50% of all cancers, and it is the most common cancer among male and the third most common among female population, which is related to the deleterious oral habits such as tobacco chewing, betel-quid chewing, tobacco smoking, reverse smoking, as well as other factors such as alcohol consumption, low socioeconomic status, poor hygiene, poor diet, and viral infections, chronic irritation from ill-fitting dentures, rough, or fractured teeth.[2],[5] The most common sites of occurrence of oral squamous cell carcinoma (OSCC) are buccal mucosa and tongue.[6]

Oral cancer affects males more frequently than females, although the ratio is equalizing, and in recent times, increased number of cases is being reported in elderly females as well as young females.[2],[7],[8] It predominantly affects middle-aged and older persons.[2] However, the incidence of OSCC in persons under the age of 45 is increasing.[9],[10]

The etiology of oral cancer is multifactorial with the most important risk factors being tobacco, excess consumption of alcohol, and betel-quid usage.[11] However, several studies in recent times report surprising increase in oral cancer in patients, often with no significant tobacco and alcohol exposure.[8],[12]

This retrospective institutional study was conducted with the aim of describing the demographic and clinicopathological profile of cases of OSCC reported at the Oral Pathology Department in Sardar Patel Postgraduate Institute of Dental and Medical Sciences, Lucknow, during a 6-year and 6-month period, to highlight the magnitude of problem and find the trend of the occurrence of OSCC in north Indian population in the state of Uttar Pradesh.


  Methods Top


In this retrospective study (January 2011 to June 2017), data of 98 OSCC biopsies were retrieved from laboratory records. It included age, gender, risk habits with duration (tobacco and alcohol consumption), any significant previous history, time of delay in diagnosis, site of the lesion and clinical presentation, and histopathological diagnosis. No identifying patient information was disclosed in the study. The study was approved by the Institutional Ethics Committee.

Statistical analysis

Both descriptive and analytical statistics were used for summarization and calculation of the data. Continuous data were summarized as the mean ± standard deviation (SD), and percentage and proportions were calculated for categorical data. Continuous groups were compared by Student's t-test. Categorical groups were compared by Chi-square test (χ2). A two-tailed (α = 2) (P < 0.05) was considered statistically significant. IBM SPSS windows version 21.0 (SPSS Inc, Chicago, USA) was used for analysis of the data.


  Results Top


A total of 98 cases of histopathologically confirmed OSCC were reported during the study period and were included in the study. Among the patients, there were 75 (76.53%) male and 23 (23.47%) female patients [Table 1].
Table 1: Prevalence of oral squamous cell carcinoma according to gender (n=98)

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The age of the patients ranged from 24 to 90 years mean (± SD) 52.29 ± 13.37 years. Most of the patients were in the age group of 40–60 years (62.24%) in both male (56.00%) and female (82.61%) patients, and it was found to be statistically significant (χ2 P = 0.0281) [Table 2]. The age of male and female patients ranged from 24 to 90 years and 40 to 75 years with mean (±SD) 51.35 ± 14.39 years and 55.35 ± 8.87 years, respectively. The difference in mean age between males and females was not statistically significant (t-test P = 0.211).
Table 2: Prevalence of oral squamous cell carcinoma in different age groups (n=98)

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No significant medical history was obtained from any of the patient records except one male patient of 52 years of age giving a previous history of carcinoma of eyelid, which was successfully treated 4 years back.

The data regarding habit history showed the most common habits were tobacco chewing, tobacco smoking, betel quid, and alcohol consumption. About 84.56% of patients had tobacco consumption habits either smokeless or smoked form.

The most common sites of OSCC, in both male and female patients, were found to be buccal mucosa and gingivobuccal sulcus (GBS) (45.92%) and alveolus (24.49%) [Table 3]. However, this occurrence of OSCC at different sites, in males and females, didnot have any statistical significance (χ2 P = 0.892). Only five patients (5.10%) presented with lesions of the white patch while 93 patients (94.90%) presented with ulceroproliferative growth.
Table 3: Primary site of occurrence of oral squamous cell carcinoma

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Most of the cases were well-differentiated OSCC (66.32%), and a small percentage (6.12%) was found to be poorly differentiated OSCC [Table 4].
Table 4: Histopathological diagnosis

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Histopathological diagnoses as per age are summarized in [Table 5]. There was no statistical significance of the association between age and histopathological category (χ2 P = 0.446).
Table 5: Histopathological diagnosis according to age

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The time of delay in diagnosis varied from 1 week to more than 1 year [Table 6].
Table 6: Time of delay in diagnosis (n=98)

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  Discussion Top


OSCC accounts for ~90% of malignant oral lesions and is widely recognized as the most frequently occurring malignant tumor of oral structures, and the mortality rate of OSCC is relatively high, with a 5-year survival rate of 50%.[13] India has the world's highest number (nearly 20%) of oral cancers with an estimated 1% of the population having oral premalignant lesions.[14]

In the present study, increased incidence of OSCC was found in males than in females with a male-to-female ratio of 3.26:1, which is consistent with other north Indian studies on oral cancer.[14] Males are more commonly affected compared to females by OSCC in both developed (male: female ratio 2.5:1) and developing (male: female ratio 3:1) countries, which may be due to easy acceptance of habits by males.[15] However, in recent time, this difference in gender distribution is reducing in the developed countries due to more females taking up tobacco-related habits including smoking.[15]

Most of the patients were in the age range of 40–60 years, which is consistent with other studies conducted in north India.[14],[16] Oral cancer is usually a disease that occurs in males after the fifth decade of life. The mean age of presentation is in the fifth and sixth decade of life in Asian populations.[17] However, a steady increase in the incidence of OSCC has been observed in patients younger than 40 years.[18] In the present study, OSCC was diagnosed in 16.33% of male patients younger than 40 years.

Tobacco consumption is a major risk factor for oral and oropharyngeal SCC.[19] There is a strong association between the use of smokeless tobacco and the risk of development of OSCC.[20] Distinct cultural practices such as betel-quid chewing as well as varying patterns of the use of tobacco and alcohol are prevalent in Asian countries, which are important risk factors that cause oral cancer.[21] The sociocultural norms and values also favor the easy availability of tobacco products. The advent of ready to use tobacco products and aggressive marketing attracts not only youths but also children.[14] In India, the efforts of the Government for deterrence of tobacco products' use prove to be inadequate when looked at the easy availability of the products and their rampant use.

In the present study, most of the patients (82.57%) had ≥5 years of tobacco and/or betel-quid chewing habit. Daily frequency and duration of tobacco and/or alcohol consumption have a direct relationship to oral cancer development.[6],[21] A study conducted in Western Uttar Pradesh in India revealed that smokeless tobacco habit (60%) was more prevalent than bidi or cigarette smoking habits (36.26%) in both males and females.[16] Another study conducted in a western city of India concluded that tobacco chewing is the major cause for the development of OSCC.[22]

The most common sites of OSCC were buccal mucosa and GBS followed by alveolus, and the findings are consistent with other studies.[14],[22],[23] The tongue is considered as the most common site of occurrence of primary OSCCs in the developed countries, but in the developing countries, betel quid and/or tobacco chewing more commonly results in cancer of the buccal mucosa.[19],[24] This is mainly because of prolonged placement of the betel quid in the buccal pouch to obtain a maximum effect as the constituents of betel quid produce a sense of well-being and increased capacity to work by stimulation of parasympathetic nervous system.[24] Similarly, smokeless tobacco tends to incite malignant degeneration at the site of tobacco placement.[18] Tobacco generates carcinogens (cancer-causing chemicals) such as tobacco-specific nitrosamines (e.g., N-nitrosonornicotine, nicotine-derived nitrosamine ketone, N'-nitrosoanatabine, and N-nitrosoanabasine) and free radicals that can impede antioxidant enzymes such as glutathione S-transferase, glutathione reductase, superoxide dismutase, catalase, and glutathione peroxidase.[11] Reactive oxygen species are generated in substantial amounts in the oral cavity during chewing.[25]

Most of the cases (66.33%) were well-differentiated OSCC, while poorly differentiated OSCCs were very few in number comprising only 6.12% of the total sample. However, other studies from India and across reported that most of OSCC cases are diagnosed as moderately differentiated OSCC, and probably, this reflects the contribution of etiological factors such as betel-quid and/or tobacco chewing toward the development of well or moderately differentiated tumors.[15],[21],[26],[27]

The time of delay in diagnosis of OSCC in most of the cases (66.32%) was found to be 2–6 months. This can be attributed to various factors such as, but not limited to, patients' negligence due to lack of knowledge and awareness, illiteracy, poverty, and possible resort to home remedies.[22] Professional delay in making a confirmatory diagnosis can also be another factor. The time interval between the onset of symptoms and the start of treatment depends on various factors such as patient's behavior, clinical course of the illness, and the quality of the health services.[28]


  Conclusion Top


This study confirms previously established demographic factors such as age, gender, and site distribution for OSCCs in north Indian patients. There are significant associations between OSCC and middle-aged group participants predominantly male. Buccal mucosa and GBS were the most common sites for OSCC. The clinicopathological profile of OSCC patients showed that majority of patients presented with well-differentiated carcinoma. The burden of oral cancer has been increasing in most Asian countries, especially in India; hence, increasing national level public awareness programs all over the country is a demand of the time for prevention, early detection and diagnosis, and to support a tobacco-free environment. When measures taken by Government so far could not deter people from using the tobacco products, whether a blanket ban on their production and sale is possible must be a subject of debate and discussion and of utmost importance to reconsider.

Financial support and sponsorship

Nil.

Conflicts of interest

There are no conflicts of interest.

 
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    Tables

  [Table 1], [Table 2], [Table 3], [Table 4], [Table 5], [Table 6]


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