Pathology of Pulmonary Neoplasia Flashcards
What is the most common death by cancer worldwide?
Lung cancer
What is the biggest cause of lung cancer?
Tobacco
What are causes of lung cancer apart from tobacco?
- Asbestos
- Environmental radon
- Occupational exposure
- Air pollution and urban environment
- Other radiation
- Pulmonary fibrosis
What is the increased risk of lung cancer caused by smoking in males and females?
RISK of cancer INCREASED 22 times in males and 12 times in females
How does passive smoking increase risk of lung cancer?
-50-100% increased risk
- Causes at least 25% of so-called non-smoking
lung cancers
Does stopping smoking stop your risk of lung cancer?
NO
- Risk reduces with abstinence but only slowly.
What is the main carcinogen in tobacco likely to give you Adenocarnomas?
N-nitrosamines
What is the main carcinogen in tobacco likely to give you Squamous SCLC?
Polycyclic aromatic hydrocarbons (PAH)
What are the 2 main pathways of carcinogenesis in the lung?
In the lung periphery and in the central lung airways
How does carcinogenesis occur in the lung periphery?
Bronchioalveolar epithelial stem cells transform causing Adenocarcinoma.
How does carcinogenesis occur in the central lung airways?
Bronchial epithelial stem cells transform causing Squamous cell carcinoma.
What kind of cancer is most lung cancers?
They are an adenocarcinoma in the peripheral of the lung
What is the carcinoma sequence of peripheral lung adenocarcinogenesis?
Atypical adenomatous hyperplasia (AAH) > Adenocarcinoma in situ > Invasive adenocarcinoma
What oncogene is mainly smoking induced?
KRAS
Which oncogenes are not related to tobacco carcinogenesis?
- EGFR
- BRAF, HER2
- ALK rearrangements
- ROS1 gene rearrangements
What are the different types of tumours of the lung?
- Benign causes of mass lesion
- Carcinoid tumour
- Tumours of bronchial glands: very rare
- Lymphoma
- Sarcoma
- METASTASES to lung are common
What are the 4 main types of carcinoma?
- Squamous cell
- Adenocarcinoma (most likely)
- Small cell carcinoma
- Large cell carcinoma
Which carcinomas are non-small cell carcinomas (NSCLC)?
- Adenocarcinoma
- Squamous cell carcinoma
- Large cell carcinomas
- Others
Which carcinoma has increased in number of cases in Scotland?
Adenocarcinoma
Features of primary lung cancer
- Probably grows ‘clinically silent’ for many years
- Presents late in its natural history
- Generally speaking, symptomatic lung cancer is fatal.
Small cell carcinoma
- Comprises about 10-15% of lung cancers.
- This type is the most aggressive and rapidly growing.
- It is strongly related to cigarette smoking.
Local effects of lung cancer
- Bronchial Obstruction
- Pleural
- Direct Invasion
- Lymph node metastases
Features of bronchial obstruction local effects
- Collapse
- Endogenous lipoid pneumonia
- Infection/abscess
- Bronchiectasis
Features of pleural local effects
- Inflammatory
- Malignant
Features of direct invasion local effects
- Chest wall
- Nerves:
Phrenic-diaphragmatic paralysis
L recurrent laryngeal -hoarse, bovine cough
Brachial plexus-pancoast T1 damage
Cervical Sympathetic-horner’s syndrome
-Mediastinum (SVS, Pericardium)
Features of lymph node metastases local effects
- Mass effect
- Lymphangitis carcinomatosa
Distant effects of lung cancer
- Distant metastases: liver, adrenals, bone, brain, skin.
- Secondary to local effects: Neural, vascular.
- Non-metastatic effects
Non-Metastatic Paraneoplastic Effects of small cell carcinoma
- ACTH, SIADH
Non-Metastatic Paraneoplastic Effects of squamous cell carcinoma
- PTH
Non-metastatic effects of lung cancer
Finger clubbing and Hypertrophic pulmonary osteoartgropathy (HPOA)
Investigation techniques for lung cancer
- Chest X-ray
- Sputum Cytology rarely used
- Bronchoscopy
- Trans-thoracic Fine Needle Aspiration
- Trans-thoracic Core Biopsy
- Pleural effusion cytology and Biopsy
- Advanced imaging techniques e.g. CT scan
What can prognostic markers be used for?
TO select patients for ADJUVANT therapy
What is the PD1/PD-L1 axis immune checkpoint in NSCLC?
- A therapeutic target
- An important biomarker
What are predictive biomarkers used for after diagnosis?
They will increasingly be used to select patients for therapy
- Adenocarcinoma e.g. EGFR, KRAS, HER2, BRAF mutations, ALK translocations etc.
- Squamous cell
- Immunotherapy in NSCLC has transformed practice.
What are the immune checkpoints adopted by tumours to avoid immune destruction?
PD1
PD-L1
CTLA4