EXAM #2: PATHOLOGY OF THE LUNG Flashcards
What are the most common malignant lesions of the lung?
Metastasis from a different organs to the lung
What is the most common BENIGN lesion of the lung?
Granuloma i.e.
- TB
- Fungus (Histoplasmosis)
What are the most common sites that metastesize to the lung?
1) Breast
2) Stomach
3) Pancreas
4) Colon
How do mets to the lung appear?
Multiple “cannonball” lesions
How does a pulmonary hamartoma appear on imaging?
“Coin lesion”
*This is a benign lesion of normal lung tissue (and cartilage) that is disorganized)
What are the vast majority of primary lung tumors?
Carcinoma i.e. neoplasia arising from the epithelium
What are the top four causes of pleural exudate?
1) Microbial invasion
2) Cancer*
3) Pulmonary infarction
4) Viral pleuritis
Especially if “blood-tinged exudate”
What is Lambert Eaton Syndrome?
Muscle weakness due to autoantibodies vs. Ca++ channels on motor end plates
Note that this is differentiated from myasthenia gravis in that it gets BETTER with activity
What type of lung cancer causes the majority of paraneoplastic sydromes?
Small cell lung cancer (neuroendocrine)
What lung cancer is hypercalcemia most commonly associated with?
Squamous cell carcinoma
*B/c is produces PTHrP
What are the sequelae of a Pancoast tumor?
1) Horner Syndrome
2) Brachial plexus dysfunction
*This is a tumor, typically of squamous cell etiology, that is located in the apex of the lung
Aside from smoking, what other exposures are associated with lung cancer?
1) Asbestos
2) Industrial hazards
3) Aromatic hydrocarbons
What are the four major types of lung cancer?
NSCLC:
1) Adenocarcinoma
2) Squamous cell carcinoma
3) Large cell carcinoma
4) Small cell carcinoma
What is never indicated for small cell lung cancer?
Surgery
What is the most common type of lung cancer?
Adenocarcinoma i.e. glandular
What gene mutations are associated with adenocarcinoma? What are these three mutations associated with?
1) KRAS in smokers
2) EGFR in individuals of Asian descent
3) ALK (anaplastic lymphoma kinase) in nonsmokers and younger patients
Where does adenocarcinoma typically develop?
Periphery i.e. most common to involve the pleura
What are the two forms of adenocarcinoma?
1) Bronchial
2) Bronchioalveolar
What is unique about bronchioalveolar adenocarcinoma (BAC)?
- Uncommon but best prognosis
- Cancer grows on walls of alveoli and bronchioles
What does BAC arise from?
Bronchioalveolar stem cells
Describe the progression of SCC.
1) Metaplasia
2) Dysplasia
3) CIS
4) Invasive carcinoma
What genetic mutations are associated with SCC?
- p53
- EGFR
Histologically, what is pathognomonic for SCC?
Keratin pearls and intercellular bridges
What mutations are associated small cell lung cancer?
- c-MYC
- Rb1
What is the treatment of choice for small cell lung cancer?
Chemotherapy
What histological finding is pathognomonic for small cell carcinoma?
“Oat cell carcinoma”
Where does small cell carcinoma arise?
Centrally
How is the diagnosis of large cell carcinoma described?
Diagnosis of exclusion
How are the large cells in large cell carcinoma described?
Undifferentiated i.e. no mucin, no glands, no keratin pearls…etc.
What are the concerning staging elements for lung cancer?
1) Larger than 3cm
2) Invasion of adjacent structures
3) Contralateral lymph nodes
*Also, note that Mets= stage 4
What are the most common sites of metastases of primary lung cancer?
1) LN
2) Adrenal gland
3) Liver
4) Brain
5) Bone
What causes carcinoid syndrome? What are the symptoms?
5-HT secretion from a carcinoid tumor causing:
1) Diarrhea
2) Flushing
3) Bronchoconstriction
4) Cyanosis
What are the major benign and malignant pleural tumors?
Benign= fibroma–most made up of collagen
Malignant= mesothelioma
