Gomez - Lung Neoplasia Flashcards
What are pulmonary hamartomas?
Benign masses in the lung
Composed of disorganized lung tissue and cartilage
Describe pulmonary lymphangioleiomyomatosis (LAM)
Proliferation of perivascular epitheliod cells
Usually in young women
Leads to a cystic emphesematous appearance of lung
Often accompanied by uterine neoplasia
Can be associated with tuberous sclerosis
Describe inflammatory myofibroblastic tumors
Proliferation of spindle-shaped fibroblasts
Rarely metastasizing
Occurs throughout body
Difficult to surgically resect, and keeps recurring
Associated with anaplastic lymphoma kinase (ALK) gene mutation
What are two important, strong initiators of lung cancer?
Polycyclic aromatic hydrocarbons
Nitrosamine
What is a good promotor of lung cancer?
Phenol
What populations are at risk for developing lung CA from radon gas?
Uranium miners
It has not been conclusively demonstrated that radon accumulation in basements can cause lung CA
Which type of lung CA is least associated with smoking?
Adenocarcinoma in situ, aka bronchioloalveolar carcinoma
What is the most common type of lung CA in female smokers?
Adenocarcinoma
What is the most common type of lung CA in all smokers?
Small cell carcinoma
What is the mnemonic for association between lung CA, location, smoking status, and related symptoms?
S sounds:
Small cell/Squamous, Smoker, Central, (paraneoplastic) Syndrome
What is the relationship between mutations in EGFR and KRAS?
They are mutually exclusive
Tumor cells that are EGFR(+) will be KRAS(-)
Tumor cells that are EGFR(-) will be KRAS(+)
What mutations are commonly present in squamous cell carcinoma of the lung?
del3p
p16 (not mutated in small cell carcinoma)
p53
RB
EGFR
What is true of using EGFR inhibitors to treat lung CA?
Can use EGFR inhibitor to treat EGFR(+) adenocarcinoma
Cannot successfully treat squamous cell carcinoma with EGFR inhibitors
Describe the pathogenesis of Pancoast tumors
Apical lung tumor
Causes pain in distribution of the ulnar nerve
Affects sympathetic ganglia, resulting in Horner syndrome (ptosis, miosis, anhydrosis)
What paraneoplastic syndrome is most commonly associated with squamous cell carcinoma?
Release of parathyroid hormone releasing peptide (PTHrP)
Causes hypercalcemia
What is Trousseau syndrome?
Hypercoagulability and thrombophlebits secondary to carcinoma
What do adenocarcinomas look like?
Glandular tissue
FIbrous hyperplasia surrounding glands
What does squamous cell carcinoma look like?
Keratinization of cytoplasm
Appearance of intracellular desmosomal bridges
What is the precursor lesion for adenocarcinoma?
atypical adenomatous hyperplasia
What are the characteristics of adenocarcinoma?
Tends to be more peripheral
Increased mucin production due to glandular nature of cancer
Positive thyroid transcription factor 1 (TTF1)
What are zellballen?
Balls of cells with mucious vacuoles
can be found in pts with adenocarcinoma
What is the problem with classifying large cell carcinomas?
They are so poorly differentiated
Probably a form of squamous cell or adenocarcinoma
Some have neuroendocrine origin
Carcinoids and atypical carcinoids are associated with mutation of which tumor suppressor gene?
MEN 1
What is the typical progression of lung CA metastasis?
Mass→regional lymph nodes→hilar lymph nodes→adrenals, liver, brain, bone
What is the composition of transudate?
Low LDH, low protein, low cholesterol fluid
Seen in CHF, cirrhosis, or nephrotic syndrome
What is the composition of exudate?
High LDH, high protein, or high cholesterol
Seen with pneumonia, pneumonitis, CA, infarct, autoimmune disorders, lymphatic blockage
What types of cancer commonly metastasize to the pleura?
Lung and breast
What markers are typically expressed by malignant mesotheliomas?
Calretenin
Mesothelin
WT-1
