Squamous cell carcinoma of lung vs Adenocarcinoma of lung
How to tell Squamous cell carcinoma of lung and Adenocarcinoma of lung apart when a board question makes them look alike.
Squamous is central cavitary PTHrP; adenocarcinoma is peripheral gland-forming/mucin-producing.
Side by side
Smoking-associated central or hilar tumor, often cavitary, with keratinization/intercellular bridges and PTHrP-mediated hypercalcemia.
Often peripheral gland-forming or mucin-producing tumor; most common lung cancer overall and common in nonsmokers.
Bronchial squamous metaplasia and dysplasia progress to invasive squamous carcinoma, classically in central airways.
Malignant glandular epithelial cells arise more peripherally and often carry targetable driver mutations in selected patients.
Central cavitary mass, smoker, hypercalcemia, keratin pearls, or intercellular bridges points squamous cell carcinoma.
Peripheral mass, gland formation, mucin, TTF-1/napsin A pattern, nonsmoker, or scar-associated lesion points adenocarcinoma.
The trap
Smoking history alone is not enough because adenocarcinoma also occurs in smokers; location and histology carry the answer.
Watch it explained
The repair move
For non-small cell subtype, ask central versus peripheral, then paraneoplastic calcium versus gland/mucin features.
Try a free question
CoreA smoker has a central cavitary lung mass and hypercalcemia from PTHrP production. Which lung cancer subtype is most likely?
Show answer and explanation
Answer: A. Squamous cell carcinoma. Squamous cell carcinoma is strongly smoking-associated, often central/cavitary, and classically causes PTHrP-mediated hypercalcemia.
Why the other choices are tempting
- B. Adenocarcinoma is often peripheral and is the most common lung cancer in nonsmokers.
- C. Small cell carcinoma is central neuroendocrine cancer with SIADH/ACTH and early metastasis.
- D. Carcinoid tumor is a neuroendocrine tumor with different behavior.
- E. Mesothelioma is pleural malignancy linked to asbestos.
Flashcards
Tap a card to flip it.
What is the fastest separator for Squamous cell carcinoma of lung vs Adenocarcinoma of lung?
Squamous is central cavitary PTHrP; adenocarcinoma is peripheral gland-forming/mucin-producing.
What clue should make you choose Squamous cell carcinoma of lung?
Smoking-associated central or hilar tumor, often cavitary, with keratinization/intercellular bridges and PTHrP-mediated hypercalcemia.
Quick answers
What is the fastest way to tell Squamous cell carcinoma of lung from Adenocarcinoma of lung?
Squamous is central cavitary PTHrP; adenocarcinoma is peripheral gland-forming/mucin-producing.
What is the key clue for Squamous cell carcinoma of lung?
Smoking-associated central or hilar tumor, often cavitary, with keratinization/intercellular bridges and PTHrP-mediated hypercalcemia.
What is the key clue for Adenocarcinoma of lung?
Often peripheral gland-forming or mucin-producing tumor; most common lung cancer overall and common in nonsmokers.
What is the common trap with Squamous cell carcinoma of lung vs Adenocarcinoma of lung?
Smoking history alone is not enough because adenocarcinoma also occurs in smokers; location and histology carry the answer.