Radiology of Lung Cancer and Staging Flashcards
What is the investigation process for lung cancer?
History and physical exam: Symptoms, risk factors (e.g., smoking), and physical signs (e.g., clubbing, lymphadenopathy).
Imaging:
Chest X-ray: Initial investigation.
CT scan: Detailed imaging to assess the tumor size, location, and spread.
PET-CT scan: To evaluate for distant metastasis.
Biopsy:
Bronchoscopy: For central tumors.
CT-guided biopsy: For peripheral tumors.
Molecular testing: For genetic mutations (e.g., EGFR, ALK) to guide targeted therapy.
Mediastinoscopy or EBUS (Endobronchial Ultrasound): To evaluate mediastinal lymph nodes for staging.
How is lung cancer staged?
TNM staging system:
T (Tumor): Size and extent of the primary tumor (T1 to T4).
N (Node): Lymph node involvement (N0 to N3).
M (Metastasis): Presence or absence of distant metastasis (M0 or M1).
Stages:
Stage I: Localized tumor (T1, T2, N0, M0).
Stage II: Larger or locally invasive tumor (T3, N1, M0).
Stage III: Regional spread (T1-T4, N2, M0).
Stage IV: Distant metastasis (M1).
Purpose of staging: Helps to determine the treatment approach (surgery, chemotherapy, radiation, or a combination).
What are the causes of a localized opacity (coin lesion) on a chest X-ray?
Benign causes:
Granulomas: Often due to previous infections (e.g., tuberculosis, histoplasmosis).
Hamartomas: Non-cancerous growths made up of normal lung tissue.
Infectious lesions: Abscesses, pneumonia, or fungal infections.
Malignant causes:
Primary lung cancer: Can present as a solitary pulmonary nodule (coin lesion).
Metastatic lesions: Secondary cancers (e.g., from breast, colon, kidney).
Other causes:
Rheumatoid nodules: In patients with rheumatoid arthritis.
Pulmonary infarcts: Due to embolism or other vascular issues.
