|Year : 2016 | Volume
| Issue : 1 | Page : 92-95
Increasing incidence of adenocarcinoma lung in India: Following the global trend?
A Mohan, AN Latifi, R Guleria
Department of Pulmonary Medicine and Sleep Disorders, All India Institute of Medical Sciences, New Delhi, India
|Date of Web Publication||28-Apr-2016|
Department of Pulmonary Medicine and Sleep Disorders, All India Institute of Medical Sciences, New Delhi
Source of Support: None, Conflict of Interest: None
Background: Lung cancer is one of the most common malignant neoplasms worldwide and accounts for more deaths than any other cancer. The clinicopathological profile of lung cancer has shown marked regional and geographical variation. Aims: We aimed to compare the demographic and pathological profile of lung cancer patients from North India with other Indian and International series. Setting and Design: A retrospective study over a period of 5 years from January 2008 to May 2013 was conducted in the Department of Pulmonary Medicine and Sleep Disorders, All India Institute of Medical Sciences, New Delhi. Patients and Methods: A total of 397 newly diagnosed patients with lung cancer from January 2008 to May 2013 were included in the study. The clinical, demographic, and pathological features were reviewed and compared with other major National and International reports. Data were entered and analyzed using SPSS software (SPSS Inc. Released 2009. PASW Statistics for Windows, Version 18.0. Chicago: SPSS Inc. Results: A total of 397 patients (86% men, mean age 57.8 years) were studied. The ratio of men to women was 7.4. Majority of patients (78.3%) were current/previous smokers. Small cell carcinoma was diagnosed in 14.6% (58) of patients while 85.4% (339) had nonsmall cell lung carcinoma (NSCLC). Within NSCLC, the most common histology types were squamous cell carcinoma (30%), followed closely by adenocarcinoma (ADC) (28.3%) and large cell carcinoma (1.7%). Majority (87%) of the patient were staged III and IV. About 30.1% patients received anti-tubercular treatment during the current episode before a diagnosis of lung cancer was made. Conclusion: The clinicopathological profile of lung cancer has undergone noticeable changes over the last four decades, especially in the increase in ADC incidence and their frequent presence in smokers. Lung cancer is often mistreated as tuberculosis in the Indian subcontinent and hence continues to be diagnosed late.
Keywords: Adenocarcinoma, lung cancer, smoking
|How to cite this article:|
Mohan A, Latifi A N, Guleria R. Increasing incidence of adenocarcinoma lung in India: Following the global trend?. Indian J Cancer 2016;53:92-5
| » Introduction|| |
Lung cancer remains a major cause of morbidity and mortality worldwide, accounting for more deaths than any other cancer. Lung cancer has been the most common cancer worldwide in the world since several decades, and in 2012, there were an estimated 1.8 million (13% of all cancers) new cases, representing 13% of all new cancers. It was also the most common cause of death from cancer, with 1.6 million deaths (19.4% of all cancer-related deaths). Compared to the western population, the prevalence of lung cancer in India appears to be increasing. According to the Indian Council of Medical Research cancer registry, 57,795 new cases were reported in 2010, which is projected to rise up to 67,000 new cases annually by the year 2020.
The observed patterns in lung cancer rates reflect the historical prevalence and variation in the trends of smoking among men and women. Incidence of the previously predominant squamous cell variety appears to be declining (although not universally), with a corresponding increase in adenocarcinoma (ADC) variety in both genders. A Chinese study of 15,427 male lung cancer patients showed that the relative frequency of ADC increased from 21.96% to 43.36% whereas squamous cell carcinoma (SCC) decreased from 39.11% to 32.23% during the period from 2000 to 2012. Whether these changes represent a global shift in lung cancer demographics is not yet clear, and regional variations have also been observed. Most reports have emerged from Europe and USA, and although several demographic reports from India have been published, the changes in clinicopathological patterns with special reference to investigation/treatment modalities have not been systematically compared. The aim of this study was to analyze the clinicopathological and the epidemiological trends in lung cancer patients from a single tertiary care center with regards to previous and current national and international data.
| » Patients and Methods|| |
This study is a retrospective analysis of 397 lung cancer cases diagnosed in the Department of Pulmonary Medicine and Sleep Disorders, All India Institute of Medical Sciences, New Delhi over a period of 5 years from January 2008 to May 2013. Only those cases with a confirmed histological or cytological diagnosis of primary bronchogenic carcinoma based on 2004 WHO classification were included. Patients with secondary lung cancer, lymphoproliferative disease, malignant pleural effusion with unknown primary, sarcomatoid tumors, and other rare varieties were excluded. Complete demographic profile, smoking status, clinical, radiological and diagnostic details, were recorded. Staging was done according to 6th edition of American Joint Committee on Cancer (AJCC) staging system based on the available clinical and radiological findings. An age cutoff of 40 years was accepted as the limit to differentiate younger from older patients. The definition of nonsmoker or never-smoker has been adapted from previous literature as a person who had never smoked or had smoked <20 cigarettes in his or her lifetime, subjects who stopped smoking for > years were labeled as “ex-smoker”, and those who have smoked ever in their life more than just occasional smoking as “smoker”. Details of various diagnostic modalities were recorded, including fiberoptic bronchoscopy and/or ultrasonography, or computed tomography (CT)-guided tissue sampling from suspected pulmonary lesion, supplemented by pleural fluid analysis and cytological examination of regional lymph nodes and metastatic deposits as appropriate. CT scan of the thorax was done in the majority of cases. CT scan of the abdomen, brain or other parts of body, bone scan, positron emission tomography-CT scan, were done as per clinical indication for diagnostic or staging purposes. General well-being and activities of daily life of the patient were quantified using Eastern Cooperative Oncology Group (ECOG) and Karnofsky Performance Status (KPS) scoring system. Data were entered and analyzed using SPSS software (SPSS Inc. Released 2009. PASW Statistics for Windows, Version 18.0. Chicago: SPSS Inc.
| » Results|| |
A total of 397 patients were analyzed (88.1% males) with mean (standard deviation [SD]) age of 57.8 (10) years (range, 29–81 years). More than half of the patients (53.6%) were in the age group of 40–60 years, 39.7% were above 60 years while 6.5% were below 40 years. The male to female ratio was 7.4:1.
Among the entire group, 315 patients (79.3%) were ever-smokers with a mean (SD) pack year of 38.2 (27.7). 74.5% of females were current/previous smokers. Bidi (an indigenous form of tobacco) and cigarette were the common modes of smoking. We could not divide these into two groups due to considerable overlap between the two.
Small cell carcinoma was diagnosed in 58 (14.6%) of patients while 339 (85.4%) had non-small cell lung carcinoma (NSCLC). Within NSCLC, the most common histology types were SCC (30%), followed closely by ADC (28.3%) and large cell carcinoma (1.7%). About 34.5% of patients grouped under NSCLC were reported as “not otherwise specified (NOS)”. Of these, 9.7% were poorly differentiated while the remaining was unclassified. Pathological sub-classification was not possible in 28.1% patients as the diagnosis was cytological. Expectedly, the most common pathological variety cancer in females was ADC, seen in 21 (44.6%), followed by SCC - 13 (27%) and small cell carcinoma - 6 (7.8%). Among female smokers, SCC and ADC were observed in equal proportions while small cell carcinoma was diagnosed exclusively in smokers.
The male to female ratio in ADC was less compared to the entire group (3.5 and 7.4 respectively). Most patients with ADC were previous or current smokers (58% and 26.4% respectively), while only 15.6% were never smokers.
Cough was the most common symptom at the time of presentation (81%) with an average duration of 7.8 months (SD, 9.7). Other symptoms were fatigue (75.6%), dyspnea (66.5%), chest pain (63.5%), loss of weight (62.2%), anorexia (56.4%), sputum production (38%), hemoptysis (34.8%), fever (31.7%), hoarseness of voice (29.5%), and superior vena cava obstruction (3%).
The right lung was more commonly involved than the left (52.3% and 44.3% respectively), followed by the mediastinum (4.1%). The most common radiological abnormality was a mass lesion, observed in 291 patients (78%), followed by presence of pleural effusion, lung collapse and consolidation.
Most patients were diagnosed through biopsy (71.6%), obtained by bronchoscopy (59%), CT guided route (27.7%), ultrasound guidance (10.8%), and semirigid thoracoscopy (2.7%). Other diagnostic modalities used were fine-needle aspiration cytology (18%), bronchoalveolar lavage/bronchial washings (4.2%), pleural fluid cytology (3.1%), and sputum examination (2.8%).
Majority of patients were classified in stage III (59%) followed by stage IV (28%), II (10.7%), and I (2%). The mean (SD) KPS prior to treatment was 72.3 (15.4), ranging from10 to 90 while the ECOG scores were 1.4 (0.8), range (0–4).
Anti-tubercular treatment was prescribed to 126 patients (31.7%) since the onset of their current symptom. Of these, only eight patients were finally confirmed with pulmonary tuberculosis (TB) based on acid-fast positivity in sputum/bronchial washings.
| » Discussion|| |
Recent studies on the epidemiology of lung cancer in India have shown that the disease continues to be diagnosed in considerably more men than women. We observed some notable differences between our lung cancer patients and those previously reported in Western and Indian literature, as depicted in [Table 1],,,,,,,,,, and [Table 2].,,,,,,,,,,, Male predominance continues and has remained almost unchanged in India over the last four decades except in a study from North-East India; where the proportions were almost equal. In North America, however, the gender gap appears to be narrowing with increasing proportion of females being diagnosed over the last decade.,, These observations could be explained by the relatively higher female smoking habits and longer life span in the West.
|Table 1: Epidemiological and pathological comparison between various Indian lung cancer series|
Click here to view
|Table 2: Comparison of the current series with previous major International reports of lung cancer|
Click here to view
The mean age of onset/diagnosis of lung cancer has remained unchanged over the last four decades. Close to 80% of our study group was current/ex-smokers (79.5% of males and 78.3% of females). These figures are comparable to other Indian studies but lower than most Western data, which reports smoking prevalence of 87–93%.,, This finding supports the possibility of other contributing factors in lung cancer etiology, such as air pollution, passive smoking, and genetic factors. Some important differences were noted between the profile of our patients compared with Western literature. Most of our patients (87%) had advanced disease (stage III/IV) at the time of diagnosis. These figures are considerably higher than most Western data, where 30–50% of lung cancer is diagnosed at a relatively early stage which is deemed operable.,, This high proportion of advanced disease has a direct impact on the quality-of- life (QOL) and survival of these patients.
Given the fact that pulmonary TB is rampant in India, it is not uncommon to find a lung cancer patient being treated for TB initially. In fact, almost a third of our patients received anti-tubercular treatment before cancer was diagnosed. The reasons for this could be multifactorial, such as a low index of clinical suspicion, tendency to treat a more common disease to assess response, inaccessibility or unavailability of adequate health resources or laboratory and diagnostic facilities. Such empirical therapy has been shown to delay the diagnosis and subsequent treatment of lung cancer up to a period of 4.5 months and may also be a factor responsible for the high proportion of cancers diagnosed at advanced stage.
The QOL of our patients, measured by ECOG and KPS scale, was average. Majority (78%) had a KPS score of 70 and higher and ECOG <2 (77%). This performance score is lower than most Western studies;, however, QOL data from most Indian reports lacks hence a direct comparison is not possible. QOL assessments find an important place in most guidelines addressing lung cancer management but are a relatively neglected area in Indian medical practice. Overall, QOL assessment has consistently been found to be a useful surrogate marker of performance status and is directly affected by the degree of symptoms, stage, and nutritional status.,
We noted that SCC and ADC were seen in almost equal proportions (25.1% and 24.1% respectively) among our patients. Expectedly, ADC was the predominant subtype in females (irrespective of smoking status), nonsmokers and the young (< years). However, it is interesting to note that almost 84% of ADC patients were either current or previous smokers. This distribution is different from most Western reports, wherein ADC is now the most common lung cancer, probably due to the trend of smoking filtered cigarettes. Overall, it appears that the clinical spectrum of lung cancer in our group is similar to other recent Indian studies. However, a definite drift probably appear with increased incidence of ADC over the last few decades.
This study had its limitations. Being a retrospective design, data regarding diagnostics and staging were incomplete, especially sub-classification of stages into A and B as per the current AJCC-7th edition. Almost 30% of patients were classified as NOS due to the absence of histology. This may have altered the true pathological frequency of various malignant subtypes. Molecular analysis such as epidermal growth factor receptor/anaplastic lymphoma kinase mutation was not available during the study period and hence was not analyzed. However, we feel that this work adds some useful information regarding the changing spectrum of lung cancer in India over the last few decades, which may have important epidemiological and statistical value for future studies.
| » Conclusion|| |
It seems that the clinicopathological profile of lung cancer has undergone noticeable changes over the last four decades, especially in the increase in ADC incidence and their frequent presence in smokers. Lung cancer is often mistreated as TB in the Indian subcontinent and hence continues to be diagnosed late.
| » References|| |
Ferlay J, Soerjomataram I, Ervik M, Forman D, Bray F. Globocon 2012; Estimated Cancer Incidence, Mortality and Prevalence Worldwide in 2012. Int J Cancer. 2014 Sep 13. doi: 10.1002/ijc.29210.
Center for Disease control and prevention. Significant decreases reported in annual lung cancer rates. J Am Med Assoc 2014;311:792.
Takiar R, Nadayil D, Nandakumar A. Projections of number of cancer cases in India (2010-2020) by cancer groups. Asian Pac J Cancer Prev 2010;11:1045-9.
Zou XN, Lin DM, Wan X, Chao A, Feng QF, Dai Z, et al.
Histological subtypes of lung cancer in Chinese males from 2000 to 2012. Biomed Environ Sci 2014;27:3-9.
Travis WD, Brambilla E, Muller-Hermlink HK. Pathology and genetics of tumours of the lung, pleura, thymus and heart. In: Harris CC, editor. World Health Organization Classification of Tumours. Lyon: IARC Press; 2004.
Greene FL, Page DL, Fleming ID, Fritz AG, Balch CM, Haller, DG, et al.
, editors. AJCC Cancer Staging Manual. 6th ed. New York: Springer-Verlag; 2002. p. 435.
Bryant A, Cerfolio RJ. Differences in epidemiology, histology, and survival between cigarette smokers and never-smokers who develop non-small cell lung cancer. Chest 2007;132:185-92.
Guleria JS, Gopinath N, Talwar JR, Bhargave S, Pande JN, Gupta RG. Bronchial carcinoma – an analysis of 120 cases. J Assoc Physicians India 1971;19:251-5.
Jindal SK, Behera D. Clinical spectrum of primary lung cancer: Review of Chandigarh experience of 10 years. Lung India 1990;8:94-8.
Gupta RC, Purohit SD, Sharma MP, Bhardwaj S. Primary bronchogenic carcinoma: clinical profile of 279 cases from mid-west Rajasthan. Indian J Chest Dis Allied Sci 1998;40:109-16.
Prasad R, James P, Kesarwani V, Gupta R, Pant MC, Chaturvedi A, et al.
Clinicopathological study of bronchogenic carcinoma. Respirology 2004;9:557-60.
Rawat J, Sindhwani G, Gaur D, Dua R, Saini S. Clinico-pathological profile of lung cancer in Uttarakhand. Lung India 2009;26:74-6.
Dey A, Biswas D, Saha SK, Kundu S, Kundu S, Sengupta A. Comparison study of clinicoradiological profile of primary lung cancer cases: an Eastern India experience. Indian J Cancer 2012;49:89-95.
Krishnamurthy A, Vijayalakshmi R, Gadigi V, Ranganathan R, Sagar TG. The relevance of “Nonsmoking-associated lung cancer” in India: a single-centre experience. Indian J Cancer 2012;49:82-8.
Noronha V, Dikshit R, Raut N, Joshi A, Pramesh CS, George K, et al.
Epidemiology of lung cancer in India: focus on the differences between non-smokers and smokers: a single-centre experience. Indian J Cancer 2012;49:74-81.
Mandal SK, Singh TT, Sharma TD, Amrithalingam V. Clinico-pathology of lung cancer in a regional cancer center in Northeastern India. Asian Pac J Cancer Prev 2013;14:7277-81.
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.
Perng DW, Perng RP, Kuo BI, Chiang SC. The variation of cell type distribution in lung cancer: a study of 10,910 cases at a medical center in Taiwan between 1970 and 1993. Jpn J Clin Oncol 1996;26:229-33.
Ouellette D, Desbiens G, Emond C, Beauchamp G. Lung cancer in women compared with men: stage, treatment, and survival. Ann Thorac Surg 1998;66:1140-3.
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.
Minami H, Yoshimura M, Miyamoto Y, Matsuoka H, Tsubota N. Lung cancer in women: sex-associated differences in survival of patients undergoing resection for lung cancer. Chest 2000;118:1603-9.
Ferguson MK, Wang J, Hoffman PC, Haraf DJ, Olak J, Masters GA, et al.
Sex-associated differences in survival of patients undergoing resection for lung cancer. Ann Thorac Surg 2000;69:245-9.
Radzikowska E, Glaz P, Roszkowski K. Lung cancer in women: age, smoking, histology, performance status, stage, initial treatment and survival. Population-based study of 20 561 cases. Ann Oncol 2002;13:1087-93.
Fu JB, Kau TY, Severson RK, Kalemkerian GP. Lung cancer in women: analysis of the national Surveillance, Epidemiology, and End Results database. Chest 2005;127:768-77.
Santos-Martínez MJ, Curull V, Blanco ML, Macià F, Mojal S, Vila J, et al.
Lung cancer at a university hospital: epidemiological and histological characteristics of a recent and a historical series. Arch Bronconeumol 2005;41:307-12.
Bhurgri Y, Bhurgri A, Usman A, Sheikh N, Faridi N, Malik J, et al.
Patho-epidemiology of lung cancer in Karachi (1995-2002). Asian Pac J Cancer Prev 2006;7:60-4.
Stewart SL, Cardinez CJ, Richardson LC, Norman L, Kaufmann R, Pechacek TF, et al.
Surveillance for cancers associated with tobacco use – United States, 1999-2004. MMWR Surveill Summ 2008;57:1-33.
Westphal FL, Lima LC, Andrade EO, Lima Netto JC, Silva AS, Carvalho BC. Characteristics of patients with lung cancer in the city of Manaus, Brazil. J Bras Pneumol 2009;35:157-63.
Jafri SH, Shi R, Mills G. Advance lung cancer inflammation index (ALI) at diagnosis is a prognostic marker in patients with metastatic non-small cell lung cancer (NSCLC): a retrospective review. BMC Cancer 2013;13:158.
Behera D, Balamugesh T. Lung cancer in India. Indian J Chest Dis Allied Sci 2004;46:269-81.
Blanchon F, Grivaux M, Asselain B, Lebas FX, Orlando JP, Piquet J, et al.
4-year mortality in patients with non-small-cell lung cancer: development and validation of a prognostic index. Lancet Oncol 2006;7:829-36.
Singh VK, Chandra S, Kumar S, Pangtey G, Mohan A, Guleria R. A common medical error: lung cancer misdiagnosed as sputum negative tuberculosis. Asian Pac J Cancer Prev 2009;10:335-8.
Wakelee HA, Dahlberg SE, Brahmer JR, Schiller JH, Perry MC, Langer CJ, et al.
Differential effect of age on survival in advanced NSCLC in women versus men: analysis of recent Eastern Cooperative Oncology Group (ECOG) studies, with and without bevacizumab. Lung Cancer 2012;76:410-5.
Schaafsma J, Osoba D. The Karnofsky Performance Status Scale re-examined: a cross-validation with the EORTC-C30. Qual Life Res 1994;3:413-24.
Anant M, Guleria R, Pathak AK, Bhutani M, Pal H, Charu M, et al.
Quality of life measures in lung cancer. Indian J Cancer 2005;42:125-32.
Mohan A, Mohan C, Pathak AK, Pandey RM, Guleria R. Impact of chronic obstructive pulmonary disease on respiratory status and quality of life in newly diagnosed patients with lung cancer. Respirology 2007;12:240-7.
Edge SB, Compton CC. The American Joint Committee on Cancer: the 7th edition of the AJCC cancer staging manual and the future of TNM. Ann Surg Oncol 2010;17:1471-4.
[Table 1], [Table 2]