Lung Cancer Prevalence in Iran by Histologic Subtypes.

BACKGROUND: Prevalence statistics are essential for cancer control in addition to incidence and mortality data. As we know, there is no published report regarding lung cancer (LC) prevalence in Iran. Herein, we provide model-based estimates of limited time LC prevalence in Iran, 2015.

MATERIALS AND METHODS: Incidence numbers of LC were extracted from Iranian National Cancer Registry reports for 2003-2009. Trends were analyzed by joinpoint regression, assuming a logarithmic poisson model. Incidence numbers were projected up to 2015, using linear regression models which were trained by corrected annual percentage changes. A Monte Carlo-based model was generated, and absolute survival rates, number of incident cases, and incompleteness of Iranian cancer registry for LC were included into it. Limited-time prevalence (within 1, 2-3, and 4-5 years from diagnosis) and its respective 95% uncertainty level (UL) were estimated by age, gender, and histopathological type.

RESULTS: Five-year prevalence was estimated to be 4.21 (95% UL: 3.37-5.38) per 100,000 adult person, with a male:female ratio of 2.01. Estimated number of patients within 1, 2-3, and 4-5 years from diagnosis were 1871 (1497-2392), 993 (770-1285), and 420 (322-550), respectively. Most prevalent form of LC were squamous cell carcinoma (802; 579-999) and adenocarcinoma (319; 230-389) in males and females, respectively.

CONCLUSION: According to our results, the most plausible estimates of number of alive LC patients within initial treatment, clinical follow-up, and cure phases were 2392, 1285, and 550 cases in Iran in 2015.