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ORIGINAL ARTICLE
Year : 2015  |  Volume : 8  |  Issue : 4  |  Page : 447-451  

Correlation of age and gender with different histological subtypes of primary lung cancer


1 Department of Pathology, J. N. Medical College, Aligarh Muslim University, Aligarh, Uttar Pradesh, India
2 Department of Radiotherapy, J. N. Medical College, Aligarh Muslim University, Aligarh, Uttar Pradesh, India

Date of Web Publication14-Jul-2015

Correspondence Address:
Ruquiya Afrose
Department of Pathology, J.N. Medical College, Aligarh Muslim University, Aligarh, Uttar Pradesh
India
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Source of Support: None, Conflict of Interest: None


DOI: 10.4103/0975-2870.160783

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  Abstract 

Background: Histological subtypes of lung carcinoma vary between gender and age groups. Younger age group has more predilections for adenocarcinoma (ACC) while squamous cell carcinoma (SCC) is more common in older age group. Gender wise, ACC is more frequent among females as compare to males. Aim: Present study analysed the distribution of histological subtypes among different age groups (younger vs. older) and gender (male vs. females) to find out predominance of any particular subtype or a specific pattern relating to age and gender in Indian population. Materials and Methods: Data of 342 patients were retrospectively analysed in terms of age, gender and pathological diagnosis. The patients were grouped into two, younger age group (≤50 years) and older age group (>50 years). Results: There were 280 (81.87%) male and 62 (18.12%) female patients. Male:female ratio was 4:51. There were 134 patients (39.18%) in younger age group and 208 (60.81%) patients in older age group. Majority of the patients (272) were nonsmall cell lung carcinoma (NSCLC) (79.53%) while 70 patients had small cell lung carcinoma (20.46%). Out of 272 patients with NSCLC, 130 (38%), were SCC, 92 (26.90%) patients had ACC and rest 50 (14.61%) patients were of large cell lung carcinoma. No significant predilection for a particular histological subtype in younger and older age group was observed. In males SCC was the most common subtype (42.14%, P = 0.0014) and in females ACC was most frequent (48.38%, P = 0.0001). Conclusion: Squamous cell carcinoma in males, ACC in females and overall SCC is the most common histological subtype. No significant correlation with age was found.

Keywords: Gender, histological subtype, lung cancer, older age, younger age


How to cite this article:
Afrose R, Akram M, Karimi AM, Siddiqui SA. Correlation of age and gender with different histological subtypes of primary lung cancer. Med J DY Patil Univ 2015;8:447-51

How to cite this URL:
Afrose R, Akram M, Karimi AM, Siddiqui SA. Correlation of age and gender with different histological subtypes of primary lung cancer. Med J DY Patil Univ [serial online] 2015 [cited 2024 Mar 29];8:447-51. Available from: https://journals.lww.com/mjdy/pages/default.aspx/text.asp?2015/8/4/447/160783


  Introduction Top


Lung cancer is currently the most frequently diagnosed major cancer in the world and one of the commonest causes of cancer mortality worldwide. It is the most common malignancy among males while among females it ranks at number four. [1]

The epidemiological and pathological profile varies among different ethnicities and geographical regions. The vast majority of cases of lung cancer occur in the sixth to eighth decades of life, with only 5% to 10% of all cases occurring in patients under 50 years of age. [2]

According to World Health Organization (WHO) classification, four major types of lung cancer are squamous cell carcinoma (SCC), adenocarcinoma (ACC), large cell lung carcinoma (LCLC) collectively known as nonsmall cell lung carcinoma (NSCLC, 90%), and small cell lung carcinoma (SCLC, 10%). [3] The relative proportions of the major categories are SCC (males 32%, females 25%), ACC (males 37%, females 47%), SCLC (males 14%, females 18%) and LCLC (males 18%, females 10%). [4]

Gradual change in the relative incidence of various histological subtypes of lung cancer has been observed in the recent past. SCC was the most common subtype in past few decades, but in recent years ACC has become the most common subtype (49%) in the United States and most of the Western and Asian countries. [4],[5],[6],[7] However, in India SCC is still reported as the commonest histological subtype in most of the series. [8]

The results from previous studies [9],[10] suggested that the histological subtypes of lung carcinoma vary between gender and age groups. Younger age group has more predilections for ACC while SCC is more common in older age group. Gender wise, ACC is more frequent among females as compare to males. [10] Study of histological subtypes of lung cancer between different age groups and gender may help to enlighten the etiopathogenesis of lung cancer.

The objective of the current study was to find out the trends of distribution of different histological subtypes between younger and older age groups and between males and females in Indian population.


  Materials and Methods Top


This study was conducted in a government tertiary care hospital of northern India. 342 patients with a diagnosis of lung cancer between January 2009 and September 2013 were identified. We have retrospectively analysed the data of these patients in terms of age, gender and pathological diagnosis. Data was retrieved from medical record of these patients. All the patients with a proven diagnosis of primary lung carcinoma with four major histological subtypes (SCC, ACC, SCLC and LCC) were included in our study. The diagnosis was based on histopathological examination (surgical or biopsy specimens) or cytopathological examination (lung, lymph node aspiration or pleural effusion). Exclusion criteria included the clinical diagnosis of lung cancer without proven pathology, histology other than above mentioned four major histological subtypes, cases in which subtyping was not possible even after immunohistochemistry examination (poorly differentiated/undifferentiated) and metastatic lung lesion with primary elsewhere. Only those cases which have distinct histo/cytomorphology were included in the study. This study was approved by the ethical committee of the institute.

The patients were grouped into two according to their age at the time of diagnosis. These groups were defined as the younger age group (≤50 years) and the older age group (>50 years) similar to criterion used in various other studies. [11] The patients in these two groups were matched for distribution of different histological subtypes of lung cancer. Gender wise distribution of these histological subtypes was also analysed. Any specific pattern or trend in the distribution of histological subtypes in relation to age and gender was noted.

Chi-square test was used for statistical analysis.


  Results Top


During January 2009 to September 2013, 342 cases of primary lung carcinoma were registered, including 280 (81.87%) male and 62 (18.12%) female. Male:female ratio was 4:51. As per criteria defined in the study, there were 134 patients (39.18%) in younger age group and 208 (60.81%) patients in older age group.

Male to female ratio in the two groups (younger vs. older) was statistically insignificant (P = 0.6234) [Table 1].
Table 1: Age group and gender comparison

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Majority of the patients (272) were NSCLC (79.53%) while 70 patients had SCLC (20.46%). Out of 272 patients with NSCLC, 130 (38%), were SCC, 92 (26.90%) patients had ACC and rest 50 (14.61%) patients were of LCLC [Table 2].
Table 2: Distribution of patients according to age group and histological subtype

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Histological subtypes distribution in two age groups (younger vs. older) was also insignificant [Table 3].
Table 3: Histology according to the age group

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In males SCC was the most common subtype (42.14%, P = 0.0014) and in females ACC was most frequent (48.38%, P = 0.0001) and this difference was statistically significant [Table 4].
Table 4: Histology according to the gender

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  Discussion Top


Present study analysed the distribution of histological subtypes among different age groups (younger vs. older) and gender (male vs. females) to find out predominance of any particular subtype or a specific pattern relating to age and gender.

In our study we have analysed 342 cases diagnosed as primary lung cancer during the study period. There were 280 (81.87%) male and 62 (18.12%) female patients. There was an overall male predominance with male:female ratio of 4:51. This ratio is in accordance with the world [1] and Indian data. [12],[13] According to ICMR Cancer Registry, male predominates with a male:female ratio of 4:5 and this ratio varies with age and smoking status. [8] Regarding the trend of male female ratio in younger versus older age group, we observed no significant difference among the two age groups (P = 0.6234). It is in contrast to some studies which have reported a high female to male ratio in younger age group. [2],[14],[15],[16] However, other studies have concluded no significant gender difference. [17],[18]

We observed that among the two different age groups defined in the study, there were 134 patients (39.18%) in younger age group and 208 (60.81%) patients in older age group. As compared to western population, [2] patients in India present at a younger age group in a significant proportion. [8],[12],[19] Our study also showed the same pattern as described in other Indian studies, having a significant proportion of younger patients. Probable reason for this pattern may be exposure to tobacco consumption at younger age in India.

According to WHO classification NSCLC comprises 80-90% and SCLC comprises 10-20% of lung cancer. [3] In our study there were 272 patients (79.53%) with NSCLC and 70 patients (20.46%) with SCLC. The distribution of histological subtypes of lung cancer has been changing over the last few decades. In past decades, SCC and SCLC were the most frequent histological subtypes of lung cancer. However in recent studies [6],[7],[20],[21] ACC has been reported as the most common histological subtype of lung cancer. In contrast to this most of the Indian studies still report SCC as the commonest subtype. [8],[12],[19] We have observed the results similar to other Indian studies. In our study SCC was the commonest (38%) histological subtype and ACC was the second most common subtype (26.90%). Contrary to this Malik et al. in their study observed that ACC was the commonest histological subtype, accounting for 39% of all lung cancer cases in a subset of Indian population. They proposed that if a careful independent pathological review is done, ACC may be the commonest histological subtype in other Indian studies as well. [22]

In his analysis Govindan et al. concluded that the incidence of SCLC is decreasing in the United States and other western countries (17.26% in 1986-12.95% in 2002). Possible explanation they suggested is the decrease in the percentage of smokers and the shift to low-tar filter cigarettes. [23] However, our study reveals a significantly higher proportion of SCLC (20.46%).

Possible explanations for this changing pattern are linked to change in the smoking behaviour of the population as well as in the composition and method to make cigarettes relatively safe. [24] Modifications in cigarette type (filter tips, lower tar and nicotine) causes smokers to inhale more deeply and thereby expose more peripheral airways and parenchymal cells to carcinogens (with a predilection to ACC). [25],[26] Higher levels of nitrates in the tobacco blends used in cigarette manufacturing have also been linked to the development of ACC. [24],[25],[27],[28] However, in India this change has not been observed and SCC remains the commonest histological subtype. [12] This can be explained by the use of bidi (tobacco wrapped in dried tendu leaf) rather than cigarette as the tobacco consuming method by a large population in India which is an unfiltered and raw method of smoking. [12] The smoke remains in central airways resulting in more SCC and SCLC.

Regarding the distribution of histological subtypes in different age groups, ACC is reported to be the predominant histological subtype in younger patients. [11],[14],[15],[16],[17] These studies proposed that etiopathogenesis in younger and older patients is different and age should be considered as an independent factor while implementing preventive measures against lung cancer. Our result does not support this observation. In our study we have observed that there was no significant difference in younger versus older age group regarding distribution of different histological subtypes [Table 3].

Regarding gender wise distribution of histological subtypes, ACC is the most common subtype of lung cancer among women. [10] However, reason for this change is unclear. Possible factors, as suggested by Janssen-Heijnen and Coebergh [29] are the increase in women smokers and change in smoking behaviour. Filter cigarettes were introduced, when women were just beginning to smoke. This has resulted in a higher baseline proportion of women with ACC.

Our data also support this gender based distribution of histological subtypes. We found SCC is the most common histological subtype in males (42.14%, P = 0.0014) and ACC among females (48.38%, P = 0.0001) and it was statistically significant. However, the difference was insignificant for SCLC and LCLC [Table 4].

Thus age and gender based variations in histological subtypes can be attributed to different patterns of past smoking behaviour.

Limitation of our study was that we have not included pattern of smoking in these age groups and gender which might explain the etiopathogenesis and distribution of various histological subtypes.


  Conclusion Top


This study has shown that SCC is still the most common histological subtype in our population. We have found a significant proportion of younger patients as compare to world data. However, no significant difference in histological subtypes in younger and older patient was observed. SCC in males and ACC in females is the most common histological subtype. More studies from multiple institutions representing different areas are needed to find out the changing pattern of lung epidemiology in India as smoking habits and other risk factors are different in our population.

 
  References Top

1.
Parkin DM, Bray F, Ferlay J, Pisani P. Global cancer statistics, 2002. CA Cancer J Clin 2005;55:74-108.  Back to cited text no. 1
    
2.
Ramalingam S, Pawlish K, Gadgeel S, Demers R, Kalemkerian GP. Lung cancer in young patients: Analysis of a surveillance, epidemiology, and end results database. J Clin Oncol 1998;16:651-7.  Back to cited text no. 2
    
3.
Travis WD. World Health Organization Classification of Tumours. Lyon: IARC Press; 2004.  Back to cited text no. 3
    
4.
Wahbah M, Boroumand N, Castro C, El-Zeky F, Eltorky M. Changing trends in the distribution of the histologic types of lung cancer: A review of 4,439 cases. Ann Diagn Pathol 2007;11:89-96.  Back to cited text no. 4
    
5.
GLOBOCAN 2002. Cancer Incidence, Mortality and Prevalence Worldwide [database online]. IARC Cancer Base No. 5. Version 2. 0. Lyon (France): IARC Press; 2004.  Back to cited text no. 5
    
6.
Charloux A, Quoix E, Wolkove N, Small D, Pauli G, Kreisman H. The increasing incidence of lung adenocarcinoma: Reality or artefact? A review of the epidemiology of lung adenocarcinoma. Int J Epidemiol 1997;26:14-23.  Back to cited text no. 6
    
7.
Travis WD, Travis LB, Devesa SS. Lung cancer. Cancer 1995;75:191-202.  Back to cited text no. 7
    
8.
Behera D. Epidemiology of lung cancer - Global and Indian perspective. J Indian Acad Clin Med 2012;13:131-7.  Back to cited text no. 8
    
9.
Devesa SS, Bray F, Vizcaino AP, Parkin DM. International lung cancer trends by histologic type: Male:female differences diminishing and adenocarcinoma rates rising. Int J Cancer 2005;117:294-9.  Back to cited text no. 9
    
10.
el-Torky M, el-Zeky F, Hall JC. Significant changes in the distribution of histologic types of lung cancer. A review of 4928 cases. Cancer 1990;65:2361-7.  Back to cited text no. 10
    
11.
Ak G, Metintas M, Metintas S, Yildirim H, Erginel S, Alatas F. Lung cancer in individuals less than 50 years of age. Lung 2007;185:279-86.  Back to cited text no. 11
    
12.
Singh N, Aggarwal AN, Gupta D, Behera D, Jindal SK. Unchanging clinico-epidemiological profile of lung cancer in north India over three decades. Cancer Epidemiol 2010;34:101-4.  Back to cited text no. 12
    
13.
Jindal SK, Behera D. Clinical spectrum of primary lung cancer: Review of Chandigarh experience of 10 years. Lung India 1990;8:94-8.  Back to cited text no. 13
  Medknow Journal  
14.
Radzikowska E, Roszkowski K, Glaz P. Lung cancer in patients under 50 years old. Lung Cancer 2001;33:203-11.  Back to cited text no. 14
    
15.
McDuffie HH, Klaassen DJ, Dosman JA. Characteristics of patients with primary lung cancer diagnosed at age 50 years or younger. Chest 1989;96:1298-301.  Back to cited text no. 15
    
16.
Skarin AT, Herbst RS, Leong TL, Bailey A, Sugarbaker D. Lung cancer in patients under age 40. Lung Cancer 2001;32:255-64.  Back to cited text no. 16
    
17.
Gadgeel SM, Ramalingam S, Cummings G, Kraut MJ, Wozniak AJ, Gaspar LE, et al. Lung cancer in patients < 50 years of age: The experience of an academic multidisciplinary program. Chest 1999;115:1232-6.  Back to cited text no. 17
    
18.
Capewell S, Wathen CG, Sankaran R, Sudlow MF. Lung cancer in young patients. Respir Med 1992;86:499-502.  Back to cited text no. 18
    
19.
Prasad R, James P, Kesarwani V, Gupta R, Pant MC, Chaturvedi A, et al. Clinicopathological study of bronchogenic carcinoma. Respirology 2004;9:557-60.  Back to cited text no. 19
    
20.
Alberg AJ, Samet JM. Epidemiology of lung cancer. Chest 2003;123:21S-49.  Back to cited text no. 20
    
21.
Vincent RG, Pickren JW, Lane WW, Bross I, Takita H, Houten L, et al. The changing histopathology of lung cancer: A review of 1682 cases. Cancer 1977;39:1647-55.  Back to cited text no. 21
    
22.
Malik PS, Sharma MC, Mohanti BK, Shukla NK, Deo S, Mohan A, et al. Clinico-pathological profile of lung cancer at AIIMS: A changing paradigm in India. Asian Pac J Cancer Prev 2013;14:489-94.  Back to cited text no. 22
    
23.
Govindan R, Page N, Morgensztern D, Read W, Tierney R, Vlahiotis A, et al. Changing epidemiology of small-cell lung cancer in the United States over the last 30 years: Analysis of the surveillance, epidemiologic, and end results database. J Clin Oncol 2006;24:4539-44.  Back to cited text no. 23
    
24.
Thun MJ, Lally CA, Flannery JT, Calle EE, Flanders WD, Heath CW Jr. Cigarette smoking and changes in the histopathology of lung cancer. J Natl Cancer Inst 1997;89:1580-6.  Back to cited text no. 24
    
25.
Stellman SD, Muscat JE, Thompson S, Hoffmann D, Wynder EL. Risk of squamous cell carcinoma and adenocarcinoma of the lung in relation to lifetime filter cigarette smoking. Cancer 1997;80:382-8.  Back to cited text no. 25
    
26.
Brooks DR, Austin JH, Heelan RT, Ginsberg MS, Shin V, Olson SH, et al. Influence of type of cigarette on peripheral versus central lung cancer. Cancer Epidemiol Biomarkers Prev 2005;14:576-81.  Back to cited text no. 26
    
27.
Wynder EL, Muscat JE. The changing epidemiology of smoking and lung cancer histology. Environ Health Perspect 1995;103:143-8.  Back to cited text no. 27
    
28.
Hecht SS, Hoffmann D. Tobacco-specific nitrosamines, an important group of carcinogens in tobacco and tobacco smoke. Carcinogenesis 1988;9:875-84.  Back to cited text no. 28
    
29.
Janssen-Heijnen ML, Coebergh JW. Trends in incidence and prognosis of the histological subtypes of lung cancer in North America, Australia, New Zealand and Europe. Lung Cancer 2001;31:123-37.  Back to cited text no. 29
    



 
 
    Tables

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


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