A worldwide trend of increasing primary adenocarcinoma of the lung

Abstract

The four major histological types of lung cancer are adenocarcinoma, squamous cell carcinoma (SQ), large cell carcinoma and small cell carcinoma. Over the past few decades, the incidence of lung adenocarcinoma has increased gradually in most countries as the most frequently occurring histological type, displacing SQ. Adenocarcinoma is the predominant type of lung cancer among lifelong non-smokers and among females. Especially in East Asian countries, the cause(s) of the increase in adenocarcinomas are not clear. Several genetic mutations specific to lung adenocarcinomas have been found, representing attractive targets for molecular therapy. Recently, the pathological classification of lung adenocarcinoma was revised by integrating the newer clinical and biological knowledge concerning this prevailing type. Additional epidemiological, pathological and genetic studies are required to better understand this type of lung cancer.

Epidemiological and Clinicopathological Characteristics of Lung Cancer in a Teaching Hospital in Iran

“…Two other histological types of lung cancer (SC and AC), with a tiny difference, ranked second and third which were similar to findings reported by others, nationally and globally (Ehteshamifar et al, 2001;Tarrahi et al, 2009;Najafi et al, 2010;Rabahi et al, 2012;Zahir and Mirtalebi, 2012;Demirci et al, 2013;Mandal et al, 2013). In some other countries, AC type of cancer was reported to be the most common histological type of lung malignancy (Rosai, 2009;Thompson et al, 2012;Nakamura and Saji, 2013) but this trend toward AC was not occurred in our study because of low percentage of female patients and probably no significant change in smoking habits in our patients.…”

“…The histological type of lung cancer which consists of 4 major classes (Petersen, 2011) is of prime importance in determining the type of therapy and prognosis. Changes in the frequency of different histological types and an increase in AC type are reported in several studies (Nakamura and Saji, 2013).…”

Trends in Lung Cancer Incidence Rates by Histological Type in 1975–2008: A Population-Based Study in Osaka, Japan

“…However, the determining factor for the increase in ADC remains unclear. 24 It has been suggested the switching from non-filtered cigarettes to filtered cigarettes in the 1960s is related to the increase in ADC and decrease in SQC and SMC. 25 However, smoking prevalence has decreased since the 1960s, except among younger females, and cigarette consumption per capita has levelled off and then decreased since the late 1970s (eFigure 4).…”

Is mitochondrial dysfunction a driving mechanism linking COPD to nonsmall cell lung carcinoma?

“…Nonsmokers who develop lung cancer tend to be younger, are more likely to be female and are more common among Asians [25]. They also have a genetic predisposition to alterations in CYP1A1 and GSTM1 genes (carcinogen metabolism), XRCC1 and ERCC2 genes (DNA repair genes) and the IL10 gene (inflammatory response) [25,26].…”

“…They also have a genetic predisposition to alterations in CYP1A1 and GSTM1 genes (carcinogen metabolism), XRCC1 and ERCC2 genes (DNA repair genes) and the IL10 gene (inflammatory response) [25,26].…”