The effect of time changes in diagnosing lung cancer type on its recorded distribution, with particular reference to adenocarcinoma

Abstract

Among lung cancers, a substantial shift over time has occurred in the recorded frequency of adenocarcinoma (AdC) relative to that of squamous cell carcinoma (SqCC). This is evident in many countries, and also in those who have never smoked. We attempted to address the extent to which this increase is real, or an artefact of changing diagnostic practices. We reviewed studies re-evaluating diagnoses using more up-to-date criteria, and studies applying standard criteria to cases collected over a long period. We also describe changes to classifications, and factors affecting diagnostic accuracy and consistency. While the four main types have long remained essentially unchanged, successive WHO classifications differ in how tumours are ascribed to these types. Despite refinement of classifications and technological advances, the decision is ultimately the pathologist's. In 11 studies, 189/1212(15.6%) originally diagnosed AdCs were reclassified as non-AdC on review, whereas 541/1564(34.6%) of non-AdCs were reclassified as AdC, increasing AdCs by 30%. Studies examining trends in the proportion of AdC were conflicting; three showing a declining trend, seven no trend, and six some increase. Some studies find lepidic (bronchioloalveolar) carcinoma, but not other AdC sub-types, increased. The rising AdC/SqCC ratio results at least partly from diagnostic changes.

Tar level of cigarettes smoked and risk of smoking-related diseases

“…Sources of bias and compensation are discussed separately below. Detailed consideration of the data on lung cancer rate trends is beyond the scope of this paper, although the interested reader might wish to refer to publications of mine suggesting alternative explanations for the trends (Lee, 2016;Lee & Gosney, 2016;Lee & Sanders, 2004).…”

“…While there is an unfortunate lack of data relating tar level (rather than filter/plain use) to histological type of lung cancer it is clear that this claim has little foundation for a number of reasons. Apart from the lack of evidence of an increased risk of adenocarcinoma in filter compared to plain cigarette smokers (Brooks et al, 2005;Lee et al, 2012;Lee & Sanders, 2004;Marugame et al, 2004;Papadopoulos et al, 2011), it is also clear that there has been a rise in relative frequency of adenocarcinoma to squamous carcinoma in non-smokers and persuasive evidence that changes in methods for classification of histological type have contributed to the observed increase in relative frequency (Lee & Gosney, 2016).…”

Reversal effect of adenovirus-mediated human interleukin 24 transfection on the cisplatin resistance of A549/DDP lung cancer cells

“…The mortality and morbidity associated with lung cancer represent a serious threat to human health ( 26 ). Lung cancer patients often have an irritating cough, expectoration, hemoptysis, and other symptoms during the early stages of the disease, and its development is related to factors such as tumor location and pathological type ( 27 ). Lung cancer is divided into non-small cell and small cell lung cancer, with non-small cell lung cancer accounting for ~80% of all cases.…”