Pul 11 - Lung Cancer Flashcards
How is lung cancer classified?
According to histological type.
- Small cell (oat cell) lung carcinoma.
- Non-small cell carcinoma (3):
- Adenocarcinoma.
- Squamous-cell carcinoma.
- Large-cell lung cancer.
-All are related to smoking: responsible for 90% of these cancers.
Which type of lung cancer is the most common?
Adenocarcinoma.
Where in the lungs does adenocarcinoma of lungs prefer?
At the peripheries of the lungs, often found in pre-existing parenchymal scars.
What is the most common type of lung cancer in non-smoking females?
Adenocarcinoma.
Which gene mutation is related to adenocarcinoma of the lungs and what tumor marker does it release?
It is related to K-ras oncogene. It is CEA-positive.
What is bronchioalveolar carcinoma?
A subtype of adenocarcinoma, it is associated with smoking (many past books say it wasn’t). The tumor cells line the alveolar walls.
What is the preferred location of brochioalveolar carcinoma?
Periphery of lung.
What can bronchioalveolar carcinoma initially present as?
As pneumonia (infiltrate on CXR).
What is the preferred location of large cell carcinoma of lung?
Periphery of lung.
What is the histology of Large Cell carcinoma of lung?
- Anaplastic cells.
- Undifferentiated cells.
- Giants cells in various pleomorphisms.
- Very poor prognosis as it responds poorly to chemo.
Where is the preferred location of squamous cell carcinoma of the lung?
Centrally located in the lungs. Often present as a hylar mass of the bronchus, or cavitated lesion on CXR.
What is the histological finding of squamous cell carcinoma?
- Keratin pearls.
- Can secrete certain hormones (PTH-related protein).
What is the most common hormone secreted by squamous cell carcinoma of the lungs?
PTH-related protein causing hypercalcemia.
Why is it called small cell carcinoma of the lung?
Because of the nucleus to cytoplasm ratio is very high.
What is the preferred location of small cell carcinoma of the lungs?
Centrally in the lung.
What hormones can small cell carcinoma of the lung secrete?
- ACTH.
- ADH.
What are the histological finding of small cell carcinoma?
- Undifferentiated and aggresive.
- Dark blue cells called “Kulchitsky cells” or enterochromaffin (EC) cells: they release serotonin.
What is small cell carcinoma associated with?
Lambert-Eaton myasthenic syndrome (LMES): autoimmune disease, which affects the neuromuscular junction calcium channels. In this pathology, the weakness improves with use. Also associated with NYC oncogenes.
What are symptoms of carcinoid syndrome?
[Bitch, its FDR]
- Bronchospasm and wheezing
- Flushing.
- Diarrhea.
- Right-sided heart lesions.
- valvular lesions and heart murmur.
What are the two most common location of carcinoid tumor and why do they have to be there to cause carcinoid syndrome?
- Lungs.
- GI tract (most common tumor of the appendix).
- They have to be in the lungs or metastatic disease from GI tract to liver because the liver inactivates the serotonin, that causes a lot of these symptoms. Or from the lungs that directly puts those substances into the venous.
Where does the Pancoast tumor occur and what syndrome does it cause?
Occurs at the apex of the lung. It causes Horner syndrome.
What are the symptoms of Horner syndrome?
- Ptosis.
- Miosis.
- Anhidrosis.
(Can also compress the recurrent laryngeal nerve, causing hoarse voice).
What region of the lungs does mesothelioma occur?
Pleura or outer lining of the lungs.
- Can also rise in the peritonium, pericardium, tunica vaginalis (sac that surrounds testes).
- There is no association of smoking and mesothelioma.
What histological findings do we see in mesothelioma?
Psommoma bodies (round collections of calcium).
What are the most common sites of lung metastasis?
- Brain.
- Bone.
- Liver.
- Adrenal.
What element increases the risk of lung cancer?
- Radon (Rn 86).
- Found in basements and coal mines.
A patient develops bronchogenic lung cancer but has never smoked. He is a coal miner. What is the cause of the cancer?
Radon gas. There is no asbestos in coal mines.
What complications can arise from lung cancer?
- Superior vena cava syndrome.
- Horner syndrome.
- Paraneoplastic syndromes:
- Squamous cell can make PTH-related hormone: Hypercalcemia
- Small cell can make ACTH: Cushing syndrome
- Small cell can make ADH: SIADH and hyponatremia.
- Small cell can make autoantibodies against calcium channels: Lambert-Eaton syndrome and weakness. - Invasion into the recurrent laryngeal nerve, causing hoarseness.
- Pleural effusion.
- Esophageal invasion causing dysphagia.
- Laryngeal invasion.
RFF: Lung cancer associated with SIADH.
Small cell lung cancer.
RFF: Tumor associated with Horner sydrome.
Pancoast tumor.
What some symptoms of lung cancer?
- Cough.
- Hemoptysis.
- Weight loss.
- Night sweats.
- Airway obstruction.
- Paraneoplastic syndromes.
