Podcast Beta
Questions and Answers
Which of the following ranks as the leading cause of cancer death in Australia?
The incidence rate of lung cancer has risen in males in Australia.
False
What is the 5-year relative survival rate for lung cancer in Australia?
17%
One of the risk factors for lung cancer is __________ exposure.
Signup and view all the answers
Match the diagnostic techniques for lung cancer with their descriptions.
Signup and view all the answers
Which lung cancer type has the highest prevalence?
Signup and view all the answers
Adenocarcinoma is more common in non-smokers than in smokers.
Signup and view all the answers
What is a common treatment for small cell carcinoma?
Signup and view all the answers
The major category of lung cancer that is usually non-resectable is _____ carcinoma.
Signup and view all the answers
Match the following lung cancer types with their characteristics:
Signup and view all the answers
Which immunohistochemical marker is commonly positive in small cell carcinoma?
Signup and view all the answers
Adenosquamous carcinoma is defined as having no glandular differentiation.
Signup and view all the answers
What histological pattern is associated with adenocarcinoma in-situ?
Signup and view all the answers
What percentage of patients with non-small cell lung carcinoma (NSCLC) present with unresectable disease?
Signup and view all the answers
Refining a diagnosis is no longer critical for patient management in NSCLC.
Signup and view all the answers
What are the most common mutations in EGFR for lung adenocarcinoma?
Signup and view all the answers
A small biopsy sample may be used for _______ and molecular studies.
Signup and view all the answers
Match the following markers and their associated types of NSCLC:
Signup and view all the answers
Which demographic shows a higher prevalence of EGFR mutations in lung adenocarcinoma?
Signup and view all the answers
Sanger sequencing is one of the techniques used to identify EGFR mutations.
Signup and view all the answers
What method combines morphology and ancillary studies for accurate subtyping of NSCLC?
Signup and view all the answers
What is the gold standard method for detecting ALK-rearranged lung adenocarcinoma?
Signup and view all the answers
Squamous cell carcinoma in the lungs occurs more frequently in males than females.
Signup and view all the answers
What type of cancer is less frequently associated with distant metastases compared to other lung cancers?
Signup and view all the answers
The use of _____ is associated with a higher likelihood of responding to pembrolizumab therapy in NSCLC patients.
Signup and view all the answers
Match the following lung cancer types with their characteristics:
Signup and view all the answers
Which of the following best describes crizotinib therapy?
Signup and view all the answers
Adenocarcinomas with ALK rearrangements are often observed in older patients who are heavy smokers.
Signup and view all the answers
What is the recommended test to identify eligibility for pembrolizumab therapy?
Signup and view all the answers
Study Notes
Lung Cancer in Australia
- Lung cancer is the leading cause of cancer death in Australia.
- It is the 5th most commonly diagnosed cancer in both males and females.
- Incidence rates have fallen in men but risen in women, resulting in a slight overall decrease.
- Prognosis is poor, with a 5-year relative survival rate of only 17%.
Risk Factors for Lung Cancer
- Tobacco Smoking: The most significant risk factor.
- Occupational & Environmental Carcinogens: Exposure to asbestos, silica, radon, heavy metals, polycyclic aromatic carbons, and diesel exhaust.
- Radiation Exposure: Increases risk of lung cancer.
- Chronic Inflammation: Conditions like tuberculosis and pulmonary fibrosis are associated with increased risk.
- Family History: Individuals with a relative diagnosed at a young age or multiple family members with lung cancer have a higher risk.
- Inherited Conditions: Conditions like Li Fraumeni syndrome and alpha-1 antitrypsin deficiency increase susceptibility to lung cancer.
Sampling Techniques for Lung Cancer Diagnosis
- Transbronchial FNA (Transbronchial Fine Needle Aspiration): Can be guided by endobronchial ultrasound (EBUS) for improved accuracy.
- Percutaneous Transthoracic FNA/Core Biopsy: Performed under CT guidance.
- Bronchial Washings & Brushings: Used to collect cells for analysis.
- Pleural Fluid Aspiration: For analyzing fluid in the pleural space.
- Endobronchial Biopsy: Direct tissue sampling from the bronchus.
- Sputum Collection: Collected to examine for cancerous cells present in the respiratory tract.
Ancillary Studies on Neoplastic Cytology/Biopsy Specimens
- Histochemical Stains: Used to identify specific components like mucin.
- Immunohistochemistry (IHC): Detects proteins in cells, aiding in classification and diagnosis.
- Sanger & Next-Generation Sequencing (NGS): Analyze DNA and RNA to detect mutations.
- Polymerase Chain Reaction (PCR) Based Techniques: Amplify DNA segments to identify markers.
- Fluorescence In-Situ Hybridization (FISH): Identifies genetic abnormalities associated with cancer.
- Electron Microscopy: Examination of cell structures at a microscopic level.
- Flow Cytometry: Measures cell properties, aiding in diagnosis and prognosis.
Major Categories of Lung Cancer
- Small Cell Carcinoma (14%): Highly aggressive, often non-resectable, and treated with chemo-radiotherapy.
- Adenocarcinoma (38%): Most common type in non-smokers, increasing in incidence.
- Squamous Cell Carcinoma (20%): Associated with smoking, locally aggressive but with less frequent metastases.
- Large Cell Carcinoma: Resected if possible, but often requires chemotherapy and radiotherapy.
- Adenosquamous Carcinoma: A mixed type of lung cancer.
- Sarcomatoid Carcinoma: A rare and aggressive type.
Small Cell Carcinoma
- Highly aggressive and associated with smoking.
- More common in men and occurs centrally in the lung.
- Frequently produces ectopic hormones.
- Widespread metastasis and a high fatality rate.
- Treated with chemoradiation.
- Microscopic characteristics: small cells with scanty cytoplasm, finely granular chromatin, and absent/inconspicuous nucleoli.
- Immunohistochemistry: CD56+, synaptophysin+, chromogranin+/-, TTF-1+.
- Electron microscopy: Neuroendocrine granules present in 2/3.
Adenocarcinoma
- Infiltrative tumor with glandular features or mucin production.
- Common in both men and women.
- Most frequent lung cancer type in non-smokers.
- Occurs predominantly in the periphery of the lung.
- Likely to metastasize to other organs, including the brain, bone, and adrenal glands.
- Adenocarcinoma In-Situ: Precancerous lesion confined to the alveolar walls.
- CT Chest: Ground glass nodule indicates adenocarcinoma in-situ.
Oncogenic Drivers of Lung Adenocarcinoma
- KRAS G12C: A specific mutation in the KRAS gene that can drive lung cancer development.
Importance of Small Samples
- Around 70% of NSCLC patients present with unresectable disease.
- A small biopsy or cytology sample may be the only available specimen.
- Diagnosis refinement is crucial for patient management.
- Careful tissue management is essential for diagnosis, IHC, and molecular studies.
Subtyping of NSCLC
- NSCLC subtyping is feasible and accurate by combining morphology and ancillary studies.
- Periodic Acid-Schiff + Diastase (PASD): Staining detects mucin.
-
Immunohistochemistry (IHC):
- TTF-1: Lung adenocarcinoma marker.
- p40 and CK5/6: Squamous carcinoma markers.
- Metastatic disease and lymphoma should be considered in the differential diagnosis.
EGFR-Mutated Lung Adenocarcinoma
- Occurs in 10-20% of Western and 30-50% of East Asian patients.
- More common in women and never smokers.
- Characterized by lepidic growth pattern.
- Mutations in exon 19 and 21 are most frequent.
- Detected through real-time PCR, Sanger sequencing, and next-generation sequencing.
- EGFR mutation predicts response to EGFR tyrosine kinase inhibitors (EGFR-TKIs).
Epidermal Growth Factor Receptor (EGFR) Signaling Pathway
- EGFR is a protein involved in cell growth and survival.
- Mutations in EGFR can lead to uncontrolled cell growth, driving lung cancer.
- EGFR-TKIs target the activated EGFR pathway to inhibit cancer cell growth.
ALK-Rearranged Lung Adenocarcinoma
- Uncommon, affecting approximately 4% of NSCLC.
- Mostly exclusive with other driver mutations.
- More common in younger patients and lighter smokers.
- Exhibits solid-signet ring and mucinous cribriform growth patterns.
- Detected by IHC, FISH (gold standard), and NGS.
ALK Fusion Oncogenes and Downstream Signaling Pathways
- ALK is another protein implicated in cell growth and survival.
- Rearrangements in ALK can lead to cancer formation.
Crizotinib Therapy for ALK+ Lung Cancer
- Crizotinib is a targeted therapy specifically for ALK+ lung cancer.
- It shows effectiveness in shrinking tumors.
Squamous Cell Carcinoma
- Infiltrative tumor characterized by keratinization and intercellular bridges.
- More common in men and heavily associated with smoking.
- Usually occurs centrally and may be preceded by squamous dysplasia/carcinoma in-situ.
- Prone to necrosis and cavitation.
- Less frequent distant metastases compared to other types.
Programmed Cell Death Ligand-1 (PD-L1) Immunohistochemistry
- PD-L1 is a protein that helps cancer cells evade the immune system.
- Immunohistochemistry stains for PD-L1 help identify patients eligible for PD-1 inhibitor therapy.
-
= 50% membrane staining of tumor cells indicates eligibility for pembrolizumab therapy.
Pembrolizumab (Keytruda) in NSCLC
- Pembrolizumab is a PD-1 inhibitor used to treat NSCLC.
- Patients with > 50% PD-L1 expression show a higher response rate to pembrolizumab.
Studying That Suits You
Use AI to generate personalized quizzes and flashcards to suit your learning preferences.
Related Documents
Description
This quiz explores the prevalence and risk factors associated with lung cancer in Australia. Learn about its impact on both genders and the role of tobacco and environmental factors. Test your knowledge on the leading cause of cancer death and understand the statistics behind this critical health issue.
