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The most likely lung cancer in a smoker!

12K views 15 replies 9 participants last post by  bebix 
#1 · (Edited)
A 70 y/o man who currently smokes cigarettes and has smoked daily for the past 40 years presents to the ER with hemoptysis. Chest X-ray shows a 5cm mass in the left lung. Based on the hx, what's the most likely diagnosis?

a) bronchogenic carcinoma
b) bronchioloalveolar carcinoma
c) large cell neuroendocrine carcinoma
d) small cell neuroendocrine carcinoma
e) squamous cell carcinoma
 
#8 ·
I don´t know if I´m right, but bronchogenic carcinoma is synonymous with lung cancer...
"Non-small cell lung carcinoma (NSCLC) accounts for approximately 80% of all bronchogenic carcinomas, and is typically classified into specific cell types. The most common types are adenocarcinoma, squamous cell carcinoma, and large cell carcinoma, although a variety of other unusual cell types have been classified according to the World Health Organization."
bronchogenic carcinomas = 80% Non-small cell lung carcinoma / 20% small cell lung carcinoma
http://chestjournal.chestpubs.org/content/117/4_suppl_1/90S.full
 
#9 ·
Answer: A) Bronchogenic adenocarcinoma

I don´t know if I´m right, but bronchogenic carcinoma is synonymous with lung cancer...
"Non-small cell lung carcinoma (NSCLC) accounts for approximately 80% of all bronchogenic carcinomas....
http://chestjournal.chestpubs.org/content/117/4_suppl_1/90S.full
Nice article, thank you! That question is from Kaplan qbank, and the answer is listed as A. I think you are right and they are referring to bronchogenic adenocarcinoma, although in the choices they have carcinoma.
Explanation:
Cigarette smoking is thought to be responsible for 85-90% of lung cancers.
Currently small cell lung cancer accounts for 15% of all lung cancers, and non-small cell lung cancer (NSCLC) accounts for 85%. The NSCLC include bronchogenic adenocarcinoma (40%), squamous cell carcinoma (25-30%),
large cell neuroendocrine carcinoma, bronchioloalveolar carcinoma and other uncommon types.

From the article Bebix posted:
Bronchogenic "adenocarcinoma accounts for 25 to 30% of NSCLC and is the most common type."
"Squamous cell carcinoma has decreased in frequency and now comprises 25% of lung cancers."
 
#13 ·
yes you are right it is bronchogenic adenocarcinoma:

goljan also says that Adenocarinomas (are the most common primary lung cancers, even more common than squamous cell carcinomas). They are shifted more peripherally.

Even though in FA it says thats adenocarinomas are not related to smoking, you have to understand that there are atleast 3-4 types of adenocarinomas. One obviously does have SMOKING relationship, while the others do not such as bronchioloalveolar and large cell carcinoma.
:eek:
 
#14 ·
Etiology
Tobacco use, uranium mining, and radon exposure are known to be associated with a risk of small cell lung cancer.

Smoking
The predominant cause of small cell lung cancer (and non-small-cell lung cancer), is tobacco smoking. Of all histologic types of lung cancer, small cell lung cancer and squamous cell carcinoma have the strongest correlation to tobacco.[12] Some 98% of patients with small cell lung cancer have a smoking history. Patients with diagnosed small cell lung cancer should be encouraged or required to stop smoking; this may contribute to improved survival.[13]

http://emedicine.medscape.com/article/280104-overview#aw2aab6b2b3aa

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Causes
About 15% of all lung cancer cases are small cell lung cancer. Small cell lung cancer is slightly more common in men than women.

Almost all cases of SCLC are due to cigarette smoking. SCLC is rare in those who have never smoked.

SCLC is the most aggressive form of lung cancer. It usually starts in the breathing tubes (bronchi) in the center of the chest. Although the cancer cells are small, they grow very quickly and create large tumors. These tumors often spread rapidly (metastasize) to other parts of the body, including the brain, liver, and bone.

http://www.nlm.nih.gov/medlineplus/ency/article/000122.htm
 
#15 · (Edited)
I emailed them about this question, and here's the response:

Squamous cell carcinoma is actually a subset of bronchogenic carcinoma, as are all the other usual types of lung cancer. Bronchogenic carcinoma simply means a malignant neoplasm of the lung arising from the epithelium of the bronchus or bronchiole. That being said, option B should read bronchogenic ADENOcarcinoma, and we will fix it. Adenocarcinoma accounts for 35-40% of all non-small cell lung cancers (NSCLC), while squamous carcinoma accounts for 25-30%. Although adenocarcinoma is the most common type in never-smokers, in general, about 90% of NSCLC in men (including adenocarcinomas) are associated with smoking. The increase in adenocarcinomas has even been associated with smoking low-tar cigarettes, but the association with smoking is strong.

Nice work guys!
 
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