Tumors of the Lung Flashcards
How do cancers progress?
The development of a malignant tumor is a multi-step process characterized by the progressive evolution and selection of a clone of transformed cells with malignant potential
Why are adenocarcinomas on the rise?
possibly because filters on cigarettes are causing deeper inhalation`
Describe the RAS signaling pathway
RTK cross-phosphorylation activates:
RAS, RAF, MEK, ERK which then enter the nucleus to promote cell growth
Describe the P13K signaling pathway
RTK cross-phosphorylation activates:
P13K, AKT1, and then mTOR which then enter the nucleus to promote cell growth
T or F. Most tumors arise from a single mutated cell
F. Most tumors are very heterozygous in the sense that different cell lines in the tumor will have evolved from different mutations so one therapy won’t kill the whole tumor
What are oncogenes?
genes (viral or cellular) which encode proteins that subvert normal growth control mechanisms and are typically caused by mutation of photo-oncogenes or can arise from environmental stimuli
T or F. Oncogenes can be introduced to humans via viruses
T.
What is the risk of lung cancer in smokers?
10% but there is a linear elation to pack-years (male lung cancer is declining and women are increasing)
2nd hand smoke produces a 2x risk of lung cancer
What environmental stimuli promote lung cancer?
- uranium
- asbestos
Lung cancer in non-smokers is usually _______
adenocarcinomas
What size lung nodule is likely cancerous?
3+cm (less than 0.8cm is usually not)
What nodule location favors malignancy likelihood?
upper lung
What nodule appearance favors malignancy?
spiculated (calcification usually favors benign)
What is a hamartoma?
abnormal mixing of the normal components of the organ
What is a choristoma?
a collection of normal organ components in the wrong organ
Describe the CXR appearance of hamartomas in the lung
usually rounded ‘coin lesions’ on CXR located in the periphery, well-circumscribed, solitary that are most likely neoplasms and not congenital
What are hamartomas typically composed of?
mature CT (often cartilage)
What clonal chromosomal translocations are common in pulmonary hamartomas?
6p21 or 12q14-15
Describe small cell carcinomas
-usually present at an advanced stage and more likely to be metastasized (aka surgery excluded from treatment)
T or F. NSCLC are more resistant to traditional chemo than SCLC
T.
What are the types of NSCLC?
- Adenocarcinoma
- Squamous Cell carcinoma
- Large cell carcinoma
What is superior ven cava (SVC) syndrome?
lung cancer causing facial swelling, headache, and blurry vision
What is superior sulcus syndrome?
accompanies a pancoast tumor that directly invades surrounding tissue (e.g. can have shoulder pain all the way down to the ulnar surface of the hand)
What is Horner’s syndrome?
results from an interruption of the sympathetic nerve supply to the eye and is characterized by the classic triad of miosis (ie, constricted pupil), partial ptosis, and loss of hemifacial sweating (ie, anhidrosis). Can happen in lung cancer
What is the 1-yr survival rate of lung carcinomas?
41%
Causes of lung carcinomas?
- tobacco smoke
- radon
What lymph nodes do lung carcinomas go to before metastasizing?
- bronchopulmonary
- hilar
- bronchial mediastinal
and then to other organs
What does a lung adenocarcinoma (been increasing over the last two decades due to cig filters) loom like on a CT scan?
like a comet (speculated peripheral mass) common in non-smokers and female smokers
What makes something an ‘adeno’ cancer?
glandular differentiation and mucin production
What is common in lung adenocarcinoma patients?
pneumonia-like consolidation (of the entire lobe) due to ‘lepidic’ growth along alveolar septa
What stain can be used to identify mucin from an adenocarcinoma?
mucicarmine stain (stains in pink)
What is lepidic growth?
cells ALONG the alveoli are larger, hyper chromatic (darker), N:C ratio is higher, and mitotic figures are present