Custom Search

Pathology of Pulmonary Adenocarcinoma

Adenocarcinoma is the most common lung cancer in women and men. Recent advances in oncology, molecular biology, pathology, imaging, and treatment have led to an increased understanding of this disease.

Read: Bronchogenic carcinoma

Adenocarcinoma In Situ (Previously known as Bronchioloalveolar Carcinoma)

Adenocarcinomas tend to be peripheral tumors and mostly involving visceral pleura.

It may be accompanied by pleural retraction and scarring.

In the past, the scarring process was believed to be the inciting stimulus for the development of carcinoma ("scar" cancer).

However, more recently it has been shown that the scarring may only represent a desmoplastic reaction to the tumor.

Often they diffusely spread within the pleural space and coat both pleural layers (pseudoepitheliomatous carcinoma).

Based on the degree of differentiation, adenocarcinoma is subdivided into: (The new IASLC-ATS-ERS lung adenocarcinoma classification: what the surgeon should know.)

Visit the folloing pages:

Adenocarcinoma In Situ (Bronchioloalveolar Carcinoma)

Papillary Carcinoma

Mucinous (colloid) carcinoma

Rare variants of adenocarcinomas include signet-ring adenocarcinoma,adenocarcinoma with enteric (goblet) and hepatoid differentiation, and adenocarcinoma with choriocarcinomatous foci.

A much rare phenomenon is pagetoid spread along the mucosa of large bronchi, often exhibiting intracytoplasmic globules.

Electron microscopy, reveals adenocarcinomas contain all major cells of bronchial tree including goblet cells, mucinous cells, non-ciliated bronchiolar cells and Clara cells.

Rare variants of adenocarcinomas include signet-ring adenocarcinoma, adenocarcinoma with enteric (goblet) and hepatoid differentiation, and adenocarcinoma with choriocarcinomatous foci.

A much rare phenomenon is pagetoid spread along the mucosa of large bronchi, often exhibiting intracytoplasmic globules.

Electron microscopy, reveals adenocarcinomas contain all major cells of bronchial tree including goblet cells, mucinous cells, non-ciliated bronchiolar cells and Clara cells.

International association for the study of lung cancer/american thoracic society/european respiratory society international multidisciplinary classification of lung adenocarcinoma. J Thorac Oncol. 2011 Feb;6(2):244-85.

" This classification provides guidance for small biopsies and cytology specimens, as approximately 70% of lung cancers are diagnosed in such samples. Non-small cell lung carcinomas (NSCLCs), in patients with advanced-stage disease, are to be classified into more specific types such as adenocarcinoma or squamous cell carcinoma, whenever possible for several reasons: (1) adenocarcinoma or NSCLC not otherwise specified should be tested for epidermal growth factor receptor (EGFR) mutations as the presence of these mutations is predictive of responsiveness to EGFR tyrosine kinase inhibitors,(2) adenocarcinoma histology is a strong predictor for improved outcome with pemetrexed therapy compared with squamous cell carcinoma, and (3) potential life-threatening hemorrhage may occur in patients with squamous cell carcinoma who receive bevacizumab. If the tumor cannot be classified based on light microscopy alone, special studies such as immunohistochemistry and/or mucin stains should be applied to classify the tumor further. Use of the term NSCLC not otherwise specified should be minimized."