In a 70 year old male who was working in asbestos factory for 10-15 years. On routine X-ray, a mass was seen in right apical region of the lung. Biopsy was taken from the mass, Which of the following is seen on electron microscopic examination –

**Core Concept**
Asbestos exposure is a well-known risk factor for developing lung cancer, particularly adenocarcinoma. The electron microscopic examination of tumor cells can reveal characteristic features that help in diagnosing the type of cancer.

**Why the Correct Answer is Right**
The correct answer is related to the presence of **desmosomes**, which are intercellular junctions that are typically seen in adenocarcinoma cells. Adenocarcinoma cells often exhibit a characteristic ultrastructural feature of having **desmosomes**, which are not typically seen in other types of lung cancers. This is due to the fact that adenocarcinoma cells often originate from the alveolar epithelium, which is a type of epithelial tissue that forms desmosomes for cell-to-cell adhesion.

**Why Each Wrong Option is Incorrect**
**Option A:** The presence of **Weibel-Palade bodies** is more characteristic of vascular endothelial cells and is not typically seen in lung cancer cells.
**Option B:** **Melanosomes** are organelles found in melanocytes and are not typically seen in lung cancer cells.
**Option C:** **Lamellar bodies** are found in type II pneumocytes and are not typically seen in adenocarcinoma cells.

**Clinical Pearl / High-Yield Fact**
Asbestos exposure is a significant risk factor for developing lung cancer, particularly adenocarcinoma. The presence of desmosomes on electron microscopic examination is a key feature that helps in diagnosing adenocarcinoma.

**Correct Answer:** C.

✓ Correct Answer: A. Neumerous long, slender microvilli