Early-stage (I-II) Non-small cell lung cancer Flashcards
Estimated annual # of new lung cancer cases diagnosed in the US and the # of deaths from lung cancers
2017 ACS estimates - 222,500 new cases and 155,870 deaths
What is the lifetime risk of developing lung cancer - in men and women? Any differences by race?
Men: 1 in 14; Women: 1 in 17
Black men have a 20% higher incidence of lung cancer than white men. Black women have a 10% lower incidence than white women
What is the 5 yr survival rate for lung cancer patients by stage?
Stage IA: 49% Stage IB: 45% Stage IIA: 30% Stage IIB: 31% Stage IIIA: 14% Stage IIIB: 5%
How many lobes are in the lung? How many segments are there per lobe?
There are 5 lobes in the lung (RUL, RML, RLLL, LUL, LLL)
The lingula is part of the LUL
There are 5 segments per lobe, except the RUL and RML have 3 and 2 segments respectively
What are the 9 N2 nodal stations?
Station 1: highest mediastinal Station 2: upper paratracheal Station 3: prevascular (3A) and retrotracheal/prevertebral (3P) Station 4: lower paratracheal Station 5: subaortic (AP window) Station 6: P-A Station 7: subcarinal Station 8: paraesophageal Station 9: pulmonary ligament
Where are the intrapulmonary and hilar nodes located?
Intrapulmonary nodes are along the secondary bronchi
The hilar nodes are along the mainstem bronchi
These are all considered N1 nodes
What are the 5 N1 nodal stations?
Station 10: hilar Station 11: interlobar Station 12: lobar Station 13: segmental Station 14: subsegmental
What are the 3 histologic subtypes of NSCLC in decreasing order of frequency?
Adenocarcinoma (>50%) > SCC (35%) > Large cell (15%)
In addition to tobacco smoke, what are 3 other environmental exposure risk factors for developing lung cancers?
Radon
Asbestos
Occupational exposure
What is the estimated RR for lung cancer in heavy smokers vs. nonsmokers?
Heavy smokers have a 20-fold excess of lung cancer
Also have a 2-3% per yr risk of tobacco induced 2nd primary cancer
What is the risk of lung cancer in former smokers compared to current smokers?
The risk of developing lung cancer in former smokers is around half that of current smokers
What is the risk of lung cancer from passive smoke exposure?
RR 1.24 for developing lung cancer from passive smoke exposure
What % of smokers develop lung cancer?
<20% of smokers actually develop lung cancer
What histology subtype of NSCLC is least associated with smoking?
Adenocarcinoma is least associated with smoking
Name 3 histologic variants of adenocarcinoma of the lung
Adenocarcinoma in situ (previously bronchoalveolar)
Acinar
Papillary
Discuss the natural history and treatment response of adenocarcinoma in situ (formerly bronchoalveolar) carcinoma
Not associated with smoking. Presents as solitary nodule or multifocally. Pneumonitic form can spread along alveoli without basement membrane invasion. These tumors have good response rates to TKIs
Name 2 variants of large cell cancer of the lung
Giant cell and clear cell
What is the most common stage at initial presentation?
Stage IV (30%)
What are the most common sites of distant metastases for lung cancer?
Bone, adrenals and brain
What are the paraneoplastic syndromes associated with lung cancers?
Hypercalcemia of malignancy - PTHrP SIADH - leads to hyponatremia Cushing - increased ACTH Lambert-Eaton syndrome Hypercoagulability (adenocarcinoma) Gynecomastia (large cell) Carcinoid (vasoactive intestinal peptide), diarrhea Hypertrophic osteoarthropathy (adenocarcinoma)
What is the cause of Lambert-Eaton syndrome? Clinically how do you distinguish L-E syndrome from myasthenia gravis?
Circulating antibodies against against presynaptic P/Q calcium channel. With repeat motion, patients with L-E have improved strength whereas MG patients fatigue with repitition
What histologic subtypes of lung cancer are associated with peripheral and central lesions?
Peripheral: adenocarcinoma, large cell
Central: squamous cell
With which histologic subtypes of lung cancer is Thyroid Transcription Factor-1 (TTF-1) staining associated?
Adenocarcinoma, nonmucinous bronchioalveolar carcinoma (adenocarcinoma in situ) and neuroendocrine tumors
TTF-1 is rare in squamous cell
In NSCLC what is the role of CXR or CT screening for high risk patients?
CXR is not recommended. The USPSTF recommends annual screening with LDCT in people between ages 55 and 80 with a greater than 30 pack-year smoking history in current smokers and those who quit <15 yrs ago
What RCT reported low dose CT screening for lung cancer?
The national lung cancer screening trial - prospective RCT comparing LDCT vs. annual CXR for 3 years
LDCT reduced RR of lung cancer death by 20%
To prevent 1 death: 320 high risk pts need to be screened
What factors define high risk group for lung cancer according to NCCN?
Age 55-74 and >30 pack-year smoking history and <15 years cessation OR age >50 and >20 pack-year history of smoking and additional risk factors that increase risk (COPD, cancer hx, FHx, ethnicity)
What is lead-time bias and how could it affect the results of a screening trial?
Lead time in diagnosis is the time between detecting the cancer from screening and when the diagnosis would have otherwise occurred due to symptoms or imaging studies. This can lead to an apparent increase in survival.
What is length-time bias and how could it affect the results of a screening trial?
Length-time bias occurs when a screening test detects cancers that take longer to become symptomatic due to the detection of slower growing or indolent cancers. This leads to an apparent increase in survival.
What is the single most clinically significant acquired genetic abnormality in NSCLC?
EGFR mutation in exon 19 and exon 21
Among patients with NSCLC, in what particular groups are the EGFR mutations common and for what do these mutations predict?
EGFR mutations only occur in ~10% but at high rates in nonsmokers, adenocarcinomas and Asians
These predict a high response rate >80% to TKIs (gefitinib, erlotinib, afatinib, osimertinib)
Is EGFR overexpression more common in SCC or adenocarcinoma?
EGFR may be overexpressed in 80-90% of SCCs vs. 30% of adenocarcinomas
What are common mechanisms associated with TKI resistance?
T790M is a point mutation that accounts for 60% of TKI resistence, usually devlop after 9-13 months of therapy
Other mechanisms: KRAS, ALK, ROS1, exon 20 insertion, small cell transformation, epithelial-mesenchymal transition phenotype
What is the initial workup for a patient suspected of having lung cancer?
H&P, focus on weight loss >5% over prior 3 months, KPS, tobacco history, neck exam for N3 disease, CBC, CMP, CT chest (include adrenals), PET/CT scan, MRI brain for presumed stage II-III, MRI for paraspinal/superior sulcus tumors, biopsy via bronch or FNA, mediastinoscopy, PFTs
What is the most cost effective first step in a patient presenting with a new lung lesion on CXR or CT?
Obtain prior imaging for comparison
What are the 3 most common presenting symptoms of NSCLC?
Dyspnea, cough, weight loss, chest pain, hemoptysis
What is the sensitivity and specificity of sputum cytology for diagnosis of lung cancer?
Sensitivity <70%, specificity >90%
Accuracy increases with more # of specimens, at least 3 are recommended
What is the sensitivity and specificity of FDG-PET compared to CT for staging of lung cancers?
PET: sensitivity 83%, specificity 91%
CT: sensitivity 64%, specificity 74%
What is the estimated % of patients who will have false + N2 nodes on PET/CT?
10-20%. N2 nodes by PET/CT need pathologic confirmation before deferring to potentially curative surgery
What is the estimated % of patients who will have false - N2 nodes based on PET/CT?
5-16%.
What is the rate of occult mets from lung cancer detected by FDG-PET?
6-18%