Lung Cancers Associated with Cystic Airspaces

Abstract

Lung cancer, the second most common malignancy in both men and women, poses a significant health burden. Early diagnosis remains pivotal in reducing lung cancer mortality. Given the escalating number of computed tomography (CT) examinations in both outpatient and inpatient settings, radiologists play a crucial role in identifying early-stage pulmonary cancers, particularly non-nodular cancers. Screening programs have been instituted to achieve this goal, and they have raised attention within the scientific community to lung cancers associated with cystic airspaces. These cancers, although they have been known for at least a decade, remain understudied. Limited investigations with small sample sizes have estimated their prevalence and explored their radiological and pathological features. Lung cancers associated with cystic airspaces exhibit varying complexities within their cystic components and demonstrate suspicious changes over time. Adenocarcinoma is the predominant histological type, often with a peripheral location. Differential diagnosis on CT scans includes inflammatory processes or emphysema-related changes. Unfortunately, prospective studies specifically analyzing the prevalence of cystic airspace-associated lung cancers are lacking. However, it is estimated that they constitute approximately one-fourth of delayed radiological diagnoses. Increased awareness among radiologists could lead to more timely identification and potentially reduce lung cancer mortality in a cost-effective manner.

Keywords: cystic airspaces; diagnosis; lung cancer; treatment.

Figure 1

Coronal chest CT (A) shows two adenocarcinomas in the left lower lobe, one with the appearance of an atypical cyst (white arrow) and the other one with the appearance of a partially solid nodule (white arrowhead). PET-CT (B) of the same patient does not show any significant metabolic activity of the two lung nodules.

Figure 2

Axial chest CT showing a small area of increased density in the right superior lobe, adjacent to cystic emphysematous area (A), that increased in size and density after one year (B) and was proven to be an adenocarcinoma.