Lung Cancer

Question 1

tumor growth and clinical presentation

Answer 1

for a single malignant cell with a doubling itme of 3-4 months to grow to a 1 cm nodule, it would take about 7-10 years

therefore, 75% of the life history of the cancer is in the undetectable stage

Question 2

major pathologic cell types of lung cancer

Answer 2

small cell carcinoma, adenocarcinoma, squamous cell carcinoma, and large cell carcinoma

the latter three have overlapping clinical behaviors and are often grouped into non-small cell lung cancer (NSCLC) - 80% of all lung cancers

Question 3

general characteristics of small cell lung cancer

Answer 3

strong relationship to cigarette smoking

only about 1% occur in nonsmokers

no known preinvasive phase or carcinoma in situ

the most aggressive of lung tumors, metastasize weidely, and are virtually incurable by surgical means

Question 4

genes frequently mutated in small cell lung cancer

Answer 4

p53 and RB1 tumor suppressor genes

high levels of anti-apoptotic protein BCL2

low frequency of expression of the pro-apoptotic protien BAX

Question 5

presentation of small cell lung cancer

Answer 5

central mass and lymphadenopathy

highly sensitive to chemotherapy and radiation initially - patient starts to deteriorate after 6-9 months

limited stage - lymph nodes and mass encopassable in one radiographic port

extensive stage - everything else

Question 6

treatment for SCLC

Answer 6

LS (1/3) -> radiation/chemotherapy

ES (2/3) -> chemotherapy

Question 7

T component of TNM staging

Answer 7

The ‘T’ component reflects the tumor size and invasiveness. T values range from 0 to 4; T0 indicates no evidence of primary tumor, while T4 indicates extensive extrapulmonary extension.

Question 8

N component of TNM staging

Answer 8

The ‘N’ component indicates the absence or presence and extent of regional lymph node metastasis. N values range from 0 to 3; N0 indicates no regional lymph node metastasis, while N3 indicates metastasis to contralateral hilar and ipsilateral and contralateral supraclavicular/scalene lymph nodes.

Question 9

M component of TNM staging

Answer 9

The ‘M’ component defines the absence or presence of tumor spread to distant lymph nodes or organ sites. M values range from 0 to 1; M0 disease indicates no distant metastasis, while M1 indicates the presence of distant metastasis.

Question 10

strategies for screening lung cancer

Answer 10

chest x-rays

sputum analysis

CT scans

Question 11

advantages of lung cancer CT screening

Answer 11

increases detection of early-stage lung cancer

improves lung-cancer specific and overall mortality in a high risk population

most realistic strategy or improving lung cancer mortality

Question 12

disadvantages of lung cancer CT screening

Answer 12

high positive rate

benefits may not extrapolate to lower risk populations

long-term risk of repetitive radiation exposure

cost

Question 13

Stage I and treatment

Answer 13

tumor of any size is found only in the lung

treatment - surgery

Question 14

Stage II and treatment

Answer 14

tumor has spread to lymph nodes associated with the lung

surgery/chemotherapy

Question 15

Stage IIIA and treatment

Answer 15

tumor has spread to the lymph nodes in the tracheal area, including chest awall and diaphragm

combination of surgery, radiation, and chemotherapy

Question 16

Stage IIIB and treatment

Answer 16

tumor has spread to the lymph nodes on the opposite lung or in the neck

combination of chemotherapy and radiation

Question 17

Stage IV and treatment

Answer 17

tumor has spread beyond the chest

chemotharapy and/or palliative (maintenance) care

Question 18

criteria for surgery in stage I/II NSCLC

Answer 18

predicted FEV1 after pneumonectomy is 1.2L

patient is not hypercapnic

patient does not have cor pulmonale

Question 19

adjuvant therapy

Answer 19

treatment to keep cancer from returning

patients with resectable disease are the only group likely to be cured of their cancer

Question 20

pulmonary manifestations of lung cancer

Answer 20

cough from endobronchial erosion and irritation

dyspnea

chest pain

hemoptysis

postobstructive pneumonia or pneumonitis

large tumors may cavitate and present as lung abscesses

Question 21

pulmonary manifestatiosn of centrall located lung tumors

Answer 21

stridor

wheezing

hemoptysis

dyspnea

chest pain in the central location

Question 22

manifestations of intrathoracic disease

Answer 22

hoarseness from invasion of the recurrent laryngeal nerve and resultant vocal cord paralysis

dysphagia as a result of esophageal compression

superior vena cava syndrome

shoulder arm pain from superior sulcus due to local extension of a tumor in the apex of the lung that compresses the nerves

ipsilateral Horner syndrome

Question 23

superior vena cava syndrome

Answer 23

characterized by plethoric apperance, distension of the venous drainage of the arm and neck, edema of the face, neck and arms

collateral venous drainage may also form

dilated veins over anterior chest

Question 24

ipsilateral Horner syndrome

Answer 24

characterized by ptosis, meiosis, and anhydrosis due to paravertebral extension and sympathetic nerve involvement of the tumors

Question 25

paraneoplastic syndromes as a result of lung cancer

Answer 25

cytokin-mediated responses to antigens from the intrathroacic lung tumor rather than the result of distant spread of cancer

manifestations of clubbing, hypertrophic osteoarthropathy, and neurologic and hormonaal abnormalities

Question 26

mainfestations of extrathoracic disease in lung cancer

Answer 26

most common are anorexia, weight loss, and fatigue

bone pain accompanies mets tot he bone

CNS involvement is low with cancer that has not spread to the lymph

patients with signs of mediastinal or distant involvement, the risk of occult brain mets increases

the adrenal gland is the most frequent site of distant mets of lung cancer

Question 27

treatment paradigms for advanced NSCLC

Answer 27

2-drug platinum-based chemotherapy improves survival and quality of life in patients iwht good PS

chemo is better than supportive care

2 drugs better than 1 drug

3 drugs not better than 2 drugs

treatment should be limited to 4-6 cycles of chemo

Question 28

hallmarks of cancer

Answer 28

self-sufficiency in growth signals

insensitiveity to antigrowth signals

tissue invasion and metastasis

limitless replicative potential

sustained angiogenesis

evading apoptosis

Question 29

targeted therapy in oncology

Answer 29

goal is to identify anti-tumor agents that target tumor-specific molecules and spare normal cells

Question 30

ideal targeted therapy drug target

Answer 30

drives tumor growth

turns on key mechanisms of cancer progression

reversible by inhibition

dispensable in normal cells

target is measureable in tumor tissue used for diagnosis

Question 31

Erlotinib

Answer 31

quinazolinamine-derived small-molecule inhibitor of the EGFR kinase

inhibits the intracellular phosphorylation of the tyrosine kinase associated with EGFR

the mechanism of clinical antitumor action of erlotinib is not fully characterized

Question 32

EGFR

Answer 32

epidermal growth factor receptor, also called ErbB1

a transmembrane receptor tyrosine kinase of human epidermal growth factor receptor (HER)

dimerizes to become activated after ligand binding

activation contributes to cell division, migration, adhesion, and survival

Question 33

Gefitinib

Answer 33

similar to erlotinib

EGFR tyrosine kinase inhibitor

Question 34

EML4-ALK fusion mutation

Answer 34

associated with adenocarcinoma histology

fusion results in activation of tyrosine kinase that enhances cell proliferation and survival

about 25% of all lung cancers in never-smokers

Question 35

crizotinib

Answer 35

small molecule tyrosine inhibitor

approved in 2011 for treating tumors that possess the EML4-ALK fusion protein

Question 36

bevacizumab

Answer 36

a monoclonal antibody to vascular endothelial growth factor (VEGF)

neutralization can inhibit tumor vascularization and block tumor growth

useful for patients with non-squamous NSCLC

Question 37

Pancoast’s Tumor

Answer 37

superior sulcus tumor

usually squamous cell

usually initial symptoms are pain, sometimes upper extremity weakness

invasion of brachial plexus, 40%

Question 38

Lambert-Eaton Syndrome

Answer 38

a syndrome that falls under paraneoplastic syndrome

similar to myasthenia gravis clinically

proximal muscle weakness and gait disturbance

strength increased with exercise

characterized by antibodies directed against voltage-gated calcium channel and interfere with normal calcium flux necessary for release of ACh

Question 39

hypertrophic osteoarhopathy

Answer 39

thoracic malignancy is the most common cause

pain is often present

more common with adenocarcinoma

clubbing is often the first clue