Association of comorbidities with the survival of non small cell lung cancer

Abstract

Lung cancer constitutes the major mortality in the world and incidence of the disease varies considerably among different ethnic population throughout the world. Palliative chemotherapy has been a choice in advance Non-Small Cell Lung Cancer NSCLC as it has a better result than best supportive care (BSC). The Primary objective of the present study was Co morbidity analysis in patients with lung cancer and the secondary objective was to see the impact of co morbidity on survival of lung cancer (NSCLC) patients. This was a retrospective observational study. This study was carried out in the Department of Oncology at Ahsania Mission Cancer Hospital, Mirpur, Dhaka. This study was carried out during the period from January 2013 to December 2013 for one year of enrollment with a follow up of 6 months up to June 2014 which makes total study period of 18 months. All patients with an age above 18 years of both sexes presented with histologically confirmed stage IIIA, IIIB & IV NSCLC (Non Small Cell Lung Cancer) were enrolled in the study. Patient‟s data were collected from the indoor and outdoor medical records of the AMCH hospital. After selection, patients were divided into comorbid and non comorbid group. Comorbidity was defined by any associated disease except for cancer. For the Kaplan Meier survival analysis patients were contacted over the phone to see the status (Dead or Alive) on the last day of the study (2014). Total number of patients in this study was 100 with median age of 60. The numbers of patients suffering from Squamous cell carcinoma is 53 patients whereas that for adenocarcinoma is 47 patients. 49 patients were at stage IIIA/IIIB and 51patients were at stage IV. In the comorbid arm 30% patient have hypertension (HTN) followed by diabetes mellitus (DM) 22% and 18% patient have both HTN and DM. Non Co morbid arm has median survival of 12.788 months (95% CI: 7.5 – 18.06) and Co Morbid has 8.0 months (95% CI: 6.81 – 9.18) and the difference is statistically Significant (P < 0.05). According to the stratified histology than there is a statistically superior survival in Non Co-Morbid Adenocarcinoma 10.42 months than Co – Morbid Adenocarcinoma 8.0 months with a P value of 0.05. In stage IIIA/IIIB non co-morbid patients have 15.45 months and co-morbid patients have 9.0 months of median survival with a non significant difference. Younger patients (below 60 group) have median survival of 7.25 and 8.0 months in Non co-morbid and co-morbid group respectively. But older Non comorbid patients (above 60 group) the survival time of 14.36 months was almost twice than that of Co-morbid patients 7.02 months and the difference is statistically significant (P<0.05). Patients with Diabetes Mellitus tend to live longer (Median OS 12.0 months 95% CI 2.3 - 21.6) than the patients with Hypertension (Median OS 7.4 months 95% CI 2.0 -12.78). This difference in survival is statistically significant (P < 0.05). We have observed that 68% of patients were alive less than a year. One year survival was observed in 27% of cases whereas two year survival was observed in 5% of overall population. Co-morbid patients had low survival months. Among 50 co-morbid patients 39 have survived less than a year, 9 patients have survived 1 year and only 2 have survived 2 year. A higher survival rate is observed in Non co-morbid patients. One year survival was observed in 18 patients and 2 year survival was observed in only 3 patients in Non co-morbid group. 29 Non co-morbid patients were found in the group of less than a year survival which indicates a lesser mortality rate than comorbid patients. The study revealed that co morbidity is strongly associated with the survival of Non Small Cell Lung Cancer patient in Bangladesh. Even co morbid elderly people are in greater risk of mortality.