Clinico-pathological profile of lung cancer in Uttarakhand

Background: Lung cancer is one of the most aggressive and prevalent type of malignancy causing high morbidity and mortality. Tobacco smoking continues to be the leading cause of lung cancer worldwide. An increasing incidence of lung cancer has been observed in India. Objective: The aim of this study was to evaluate the clinico, a pathological profile of the lung cancer in hilly state of Uttrakhand. Materials and Methods: We performed a retrospective analysis of histopathologically proven cases of bronchogenic carcinoma admitted in our hospital from January 1998 to August 2005. Results: Our study included 203 patients with confirmed cases of lung cancer. Male to female ratio was 8.2:1. The common age group being 40-60 years, 9.86% of the patients were less than 40 years old age. Smoking was found to be the main risk factor in 81.77% patients. The most frequent symptom was cough (72.90%) followed by fever (58.12%). The most common radiological presentation was mess lesion (46.31%). The most common histopathological type was squamous cell carcinoma (SCC) (44.83%) followed by adenocarcinoma (19.78%) and small cell lung carcinoma (SCLC) (16.75%). The majority patients (73.29%) were diagnosed in the later stages of the disease (III B and IV). Conclusion: It was found out that SCC was the most frequent histopathological form. SCLC predominates below 40 year and SCC over 60 years of age. Smoking still remains the major risk factors in pathogenesis of lung cancer.


INTRODUCTION
Lung cancer is believed to be the most common fatal neoplastic disease in the world today.It is responsible for 28% of all the cancer related deaths. [1]In the developed countries, incidence and mortality from lung cancer in females is rising, whereas it is declining in males.Lung cancer is responsible for approximately one million deaths per year at present, and it is estimated to rise to three million per year by the year 2010.
Progressive survival extension and increasing cigarette smoking has led to a numerical rise of patients with primary lung cancer in India.It is in accordance with the epidemiological data from western countries, which shows rising prevalence of the disease in Indian population. [2]Smoking is the cause for more than 85% of the bronchogenic carcinoma cases. [3,4]According to the world health organization (WHO) classification formulated in 1999; there are six major types of malignant epithelial non-small cell lung carcinoma (NSCLC) and small cell lung carcinoma (SCLC). [5]The proportions of histopathological to fiber-optic bronchoscopy and/or percutaneous fine needle aspiration biopsy (FNAB) under imaging guidance.
The Ethical committee of the Institute has approved the study.
The most common histopathological type was SCC (44.83%), followed by adenocarcinoma (19.70%), and SLCC (16.75%) [Table 3].The majority of patients (73.29%) were diagnosed in the later stages of the disease.The patients presented to their physician, on an average, 112 days (range 30-270), after the onset of symptoms.

DISCUSSION
Most of our study belonged to the patients of age group between 40-60 years, with a male predominance (M:F ratio 8.2:1).Smoking was the most common predisposing factor, which included cigarettes, beedis, hookah, etc.8][9][10] In contrast to our study, Belcher JR [11] found that in USA and UK, the male: female ratio was approximately 5:1 in 1970 but fell to around 2.5:1 in 1982.This is because of the striking increase in cigarette smoking in western women.
The prevalence of respiratory system malignancies is quite variable in different parts of India.In most studies, including reports of National Cancer Registry Program (NCRP) [12,13] from Bhopal, Delhi, and Mumbai; and other studies; [12,14] laryngeal cancer was the most common site.The present study was in agreement with those where lung was the topmost site for malignancy in males.
One important observation made in our study is the delay in presentation of patients to their attending physician.Majority of the cases were misdiagnosed as tuberculosis and treated at various other centers, there by causing a delay in diagnosis.
In our study, the delay in seeking treatment was observed to vary from 4-6 months, which is similar to another study. [15]he diagnosis of cancer in an individual not only affects the person physically but produces significant psychological disturbance too.A study from Tata Memorial Hospital, Mumbai, [16] analyzing the psychological state of patients suffering from cancer, concluded that 89% of the patients used denial as a mental defense mechanism, leading to delay in seeking medical help for the confirmation and treatment of cancer.Psychological reasons such as, denial of illness, fear of cancer, fear of its treatment, and domestic difficulties were the most common causes of delay in seeking treatment.This emphasizes the need for patient counseling as well as more effective methods for early detection of lung cancer cases by general practitioner.
Our data shows that unexplained cough of several weeks is the commonest symptoms along with fever, weight loss, chest pain, and shortness of breath.This is similar to reports published in the literature from different part of India. [10,17,18]e pattern of lung cancer has been changing in the West.
Lung cancer is being increasingly diagnosed in women and adenocarcinoma has over taken SCC as the most common histological cell type. [19]However, the pattern seen at our hospital was different.SCC was still the commonest cell type seen, followed by adenocarcinoma and SLCC.17,18] This difference in histopathology may be due to the fact that smoking is less prevalent among women in India as opposed to the West, where it is rising; and urbanization, that exposes the patient to other carcinogens, risk factors or a complex interaction among gender, race, smoking status in West.
Bronchoscopy is the most useful investigation in the evaluation of the patient suspected of endobronchial lung cancer.Tumors that were beyond bronchoscopic vision, are difficult to reach and require the other technique. [20]NAB done under CT is the investigation of choice for peripherally situated lesions, which has very high complication rates as seen in various international, [21][22][23] and Indian studies. [24,25]In our study, the overall yield with bronchoscopy was 48.77% and with FNAB was 43.84%.
The commonest radiological finding seen in present study was mass followed by collapse consolidation with slight predominance of right lung; similar to reports published in the literature. [10,26]The adenocarcinoma commonly manifested as peripheral mass or a malignant pleural effusion.Similar finding were also reported in other studies. [27,28]The SCLC presented commonly as central lesion, which was in agreement with other studies. [19,27,29]

CONCLUSION
This study has shown smoking as the principle risk factor in the causation of lung cancer among men.Primary lung cancer should always be suspected in a person presenting with unexplained cough of several weeks with other symptoms such as weight loss and fever with nonresolving collapseconsolidation on chest radiograph; and further investigations should be carried out to rule lung cancer.Majority of the cases were misdiagnosed as tuberculosis and treated by antitubercular treatment, thereby causing delay in diagnosis, this emphasized the need for more effective methods for early detection of lung cancer cases among general population.