Modified histologic classification as a prognostic factor in pulmonary adenocarcinoma

Area of Science:

• Pulmonology
• Oncology
• Pathology

Background:

• Pulmonary adenocarcinoma exhibits significant histologic heterogeneity, impacting prognosis.
• The 2011 International Association for the Study of Lung Cancer (IASLC), American Thoracic Society (ATS), and European Respiratory Society (ERS) classification emphasizes predominant patterns.
• Limited research details histologic changes and prognosis in resected pulmonary adenocarcinoma specimens.

Purpose of the Study:

• To investigate the prognostic significance of histologic patterns in pulmonary adenocarcinoma.
• To evaluate a modified classification system for pulmonary adenocarcinoma based on histologic patterns.

Main Methods:

• Analysis of 125 surgically resected pulmonary adenocarcinoma cases.
• Classification into three groups based on predominant lepidic, papillary, acinar, solid, or micropapillary patterns, with specific thresholds for solid/micropapillary components.
• Utilized Kaplan-Meier survival analysis and Cox regression for prognostic evaluation.

Main Results:

• Acinar (45.8%) and solid (32.2%) patterns were most common.
• Transitional areas indicating gradual dedifferentiation were frequently observed.
• The modified classification significantly correlated with disease-free and overall survival (P=.026 and P=.010) and was an independent prognostic factor for overall survival (P=.016).

Conclusions:

• Pulmonary adenocarcinoma displays heterogeneous histologic patterns with evidence of gradual dedifferentiation.
• The proposed modified histologic classification serves as a crucial prognostic indicator for patients with pulmonary adenocarcinoma.