Pneumonic-type lung adenocarcinoma with different ranges exhibiting different clinical, imaging, and pathological characteristics

Abstract

Background: Pneumonic-type lung adenocarcinoma (PLADC) with different ranges might exhibit different imaging and clinicopathological features. This study divided PLADC into localized PLADC (L-PLADC) and diffuse PLADC (D-PLADC) based on imaging and aimed to clarify the differences in clinical, imaging, and pathologic characteristics between the two new subtypes.

Results: The data of 131 patients with L-PLADC and 117 patients with D-PLADC who were pathologically confirmed and underwent chest computed tomography (CT) at our institute from December 2014 to December 2020 were retrospectively collected. Patients with L-PLADC were predominantly female, non-smokers, and without respiratory symptoms and elevated white blood cell count and C-reactive protein level, whereas those with D-PLADC were predominantly male, smokers, and had respiratory symptoms and elevated white blood cell count and C-reactive protein level (all p < 0.05). Pleural retraction was more common in L-PLADC, whereas interlobular fissure bulging, hypodense sign, air space, CT angiogram sign, coexisting nodules, pleural effusion, and lymphadenopathy were more frequent in D-PLADC (all p < 0.001). Among the 129 patients with surgically resected PLADC, the most common histological subtype of L-PLADC was acinar-predominant growth pattern (76.7%, 79/103), whereas that of D-PLADC was invasive mucinous adenocarcinoma (80.8%, 21/26). Among the 136 patients with EGFR mutation status, L-PLADC had a significantly higher EGFR mutation rate than D-PLADC (p < 0.001).

Conclusions: L-PLADC and D-PLADC have different clinical, imaging, and pathological characteristics. This new imaging-based classification may help improve our understanding of PLADC and develop personalized treatment plans, with concomitant implications for patient outcomes.

Keywords: Epidermal growth factor receptor; Pneumonic-type lung adenocarcinoma; Tomography (X-ray computed).

Fig. 1

Flow diagram for this study

Fig. 2

L-PLADC in a 65-year-old man without symptoms. a, b Axial CT images of the lung window indicate a localized consolidation with irregular air bronchogram, GGO component, and pleural retraction (red arrow) in the right upper lobe. c Photomicrograph (hematoxylin and eosin staining, ×200) of surgical specimens confirmed LADC with an acinar-predominant pattern

Fig. 3

D-PLADC in a 49-year-old man with cough and sputum for 6 months. a–c Axial CT images of the lung window indicate diffuse consolidation with interlobular fissure bulging, air space, GGO, irregular air bronchogram, and coexisting nodules in bilateral multiple lobes. d–e Axial CT images of the mediastinal window at unenhanced scan (d) and arterial phase (e) indicate hypodense sign and CT angiogram within consolidation, respectively. f Photomicrograph (hematoxylin and eosin staining, ×400) of biopsy specimens confirmed invasive mucinous adenocarcinoma

Fig. 4

Distribution diagrams for histological subtypes of patients with L-PLADC and D-PLADC. Notes: Data are presented as %