NSCLC Flashcards
What is the treatment paradigm for Stage I-II node negative lung cancer?
(T1-2bN0M0 disease)
Medically operable:
Lobectomy + Mediastinal Lymph node dissection
Chemotherapy for Stage II, debatable in IB cases (LACE)
PORT if + margin and not re-resectable
Medically inoperable:
SBRT- perferred over conventional EBRT
Phase III TROG CHISEL study demonstrated superior outcomes in patients randomised to stereotactic radiotherapy versus those receiving standard external beam radiotherapy
Concurrent chemoRT 60GY/30# if not SABR candidate
For treatment purposes NSCLC can be divided into Early and Late based on:
1) Early = <Stage III
2) Late Stage III
Stage III is node +veor T4 disease,
with the exception that T1-2 w/ +ve N1 node (i.e. Ipsilateral peribronchial and/or ipsilateral hilar LNs = stations 10–14) is stage II (i.e early).
Define stage III NSLC
1) Either T4 = >7cm OR Satellite nodules in different lobes ipsilateral lung, or invasion: thoracic structures beyond pericardium, phrenic n. or chest wall (these are T3)
2) Any nodal disease, except N1 with only T1 (<=3cm) or T 2 (>3cm, <=5cm - without invasion)
In NSCLC contrast the definition of T3 and T4 disease:
In T3 disease, any satellite nodule needs to be within the same lobe
In T4 in different lobes same lung
Invasion in T3 is parietal pericardium, chest wall, or phrenic nerve. T4 is any other structure.
Size: T4 is >7cm, T3 is >5cm to =7cm.
In NSCLC define “peripheral tumour”
“peripheral tumour” = more than 2cm from bronchial bifurcation.
Define the “N1 nodes”
Ipsilateral peribronchial and/or ipsilateral hilar LNs (stations 10–14)
Poor prognostic factors for NSCLC:
Stage,
weight loss >5% in 3 months,
KPS <90,
age >70,
+LVSI,
Marital status (single)
Indications for PORT in NSCLC
+ve micro margins or gross residual disease
1) stage I-II patients PORT not indicated in completely resected as per meta-analysis.
2) Stage III - Lung ART RCT study looked at completely resected N2 disease - found no benefit (DFS or OS) to PORT 54/30 in completely resected N2 disease.
PORT-C study confirms this. OS at 3yrs is about 80%
What histology subtype of NSCLC is least associated with smoking?
Adenocarcinoma
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: SCC, carcinoid
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 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
Is EGFR overexpression more common in SCC or adenocarcinoma?
EGFR may be overexpressed in 80-90% of SCCs vs. 30% of adenocarcinomas
