First Aid Pathology Pt 3: Lung cancer and abscess Flashcards
What symptoms does lung cancer present with?
Cough, hemoptysis, bronchial obstruction and wheezing
How does lung cancer appear on a CXR and CT scan?
CXR: pneumonic “coin” lesion
CT: noncalcified nodule
What are the common sites of metastasis for lung cancer?
“Lung mets ‘Love Affective Boneheads And Brainiacs’”
Liver, adrenals, bone, brain
What might happen if lung cancer metastasizes to the liver?
Jaundice and hepatomegaly
Which types of cancers tend to spread to the lung?
Breast, colon, prostate and bladder
What are the complications of lung cancer?
SPHERE
Superior vena cava/thoracic outlet syndromes
Pancoast tumour
Horner’s syndrome
Endocrine (paraneoplastic)
Recurrent laryngeal nerve compressions (voice hoarseness)
Effusions (pleural or pericardial)
How might lung cancer cause horner syndrome?
The growing tumour can cause compression of the sympathetic ganglion (the stellate ganglion), resulting in a range of symptoms known as Horner’s syndrome.
What are the risk factors for lung cancer?
Smoking, secondhand smoke, radon, asbestos and FH
What commonly causes squamous and small cell carcinomas?
“Squamous and Small cell carcinomas are Sentral (central) and caused by Smoking”
List the different types of primary lung cancers, which is the most common? Which parts of the lung does each affect?
Small cell: small cell (oat cell) carcinoma: central
Non-small cell:
- adenocarcinoma (most common): peripheral
- SCC: central
- large cell carcinoma: peripheral
- bronchial carcinoid tumour: central or peripheral
Describe the histological appearance of small cell (oat cell) carcinomas
*including what lab tests are positive
It’s a neoplasm of neuroendocrine Kulchitsky cells (small dark blue cells)
Positive lab tests: chromogranin A, neuron-specific enolase, synaptophysin
Describe the pathology of small cell (oat cell) carcinoma, what can it produce?
Can be undifferentiated to very aggressive and produces (4 As)
1. ACTH: causing Cushing’s syndrome
- ADH: body retains too much water
- Antibodies against presynaptic Ca2+
a) channels: lambert Eaton myasthenic syndrome - interferes with the ability of nerve cells to send signals to muscle cells
a) neurons: paraneoplastic myelitis, encephalitis, subacute cerebellar degeneration - Amplification of myc oncogenes is common
How is a small cell (oat cell) carcinoma managed?
Chemotherapy with/without radiotherapy
Who is more commonly affected by adenocarcinomas? What genetic mutations and symptomatic feature is it associated with?
Women, more likely to arise in nonsmokers
Activating mutations include KRAS< EGFR and ALK
Associated with hypertrophic osteoarthropathy (clubbing)
What would a bronchoalveolar subtype (adenocarcinoma in situ) CXR show?
Hazy infiltrates similar to pneumonia
Describe the histological appearance of adenocarcinomas and its bronchoalveolar subtype
Adenocarcinoma: glandular pattern, often stains mucin +
Bronchoalveolar subtype: grows along the alveolar septa creating an apparent “thickening” of the alveolar walls, has tall columnar mucus containing cells
Describe the histological appearance of SCCs in the lung
Keratin pearls and intracellular bridges
Describe the pathology characteristics of SCCs in the lung
Arises from the bronchus, associated with the 3 Cs:
Cavitation, cigarettes, hyperCalcemia (which produces PTHrP)
Describe the histological appearance of large cell carcinomas in the lung
Pleomorphic giant cells
Describe the pathology characteristics of large cell carcinomas in the lung, what is it associated with, how is it treated and what is the prognosis like?
It is a highly anaplastic undifferentiated tumour with a poor prognosis. It is less responsive to chemo and must be removed surgically, has a strong association with smoking
Describe the histological appearance of bronchial carcinoid tumours in the lung, what positive lab test can be found?
Nests of neuroendocrine cells, positive chromogranin A
How is the prognosis for bronchial carcinoid tumours? Name three symptoms and what causes them
Good prognosis as it rarely metastasizes, the symptoms can be due to mass effect or carcinoid syndrome and can include wheezing, diarrhea and flushing (what da fuc)
What is a lung abscess and what causes one?
A localized collection of pus within the parenchyma which can be caused by
1. Aspiration of oropharyngeal contents (especially in patients predisposed to going unconscious like alcoholics and epileptics)
- Bronchial obstruction (i.e in cancer)
What do air-fluid levels on a CXR investigating a lung abscess suggest? What are some plausible causative agents?
Cavitation, can be caused by anaerobes (i.e Bacteroides, fusobacterium) or S.aureus
How is a lung abscess treated?
Antibiotics, drainage or surgery
Where is a lung abscess secondary to aspiration more commonly found? Describe how the location differs depending on the patient’s position
More commonly found in the R lung:
RLL: if the patient is upright
RUL or RML: if the patient is lying down
What is a Pancoast tumour and what else is it known as?
A tumour in the lung’s apex, also known as superior sulcus tumour
What can a Pancoast tumour cause and what are resulting complications?
Can cause Pancoast syndrome by compressing/invading the surrounding local structures: LSSBBP
- Recurrent laryngeal nerve ->hoarseness
- Stellate ganglion -> horner’s
- SVC -> SVC syndrome
- Brachiocephalic vein -> brachiocephalic syndrome
- Brachial plexus -> sensorimotor deficits
- Phrenic nerve -> hemidiaphragm paralysis
How would compression of the phrenic nerve in Pancoast syndrome be evident on a CXR?
Would see hemidiaphragm elevation
Name three findings associated with Horner’s syndrome
Ipsi/unilateral ptosis (droopy eyelid), miosis (excessive constriction of the pupil), anhidrosis (inability to sweat normally)
Describe what happens in superior vena cava syndrome
Obstruction of the SVC impairs the drainage from the
- Head: Facial plethora
- Neck: jugular venous distension
- Upper extremities: edema
What commonly causes SVC syndrome?
Malignancy (i.e mediastinal tumour, Pancoast tumour), thrombosis
Why is SVC syndrome considered a medical emergency?
If the obstruction is severe it can raise the intracranial pressure (causing headaches and dizziness), increasing the risk of an aneurysm/rupture of the intracranial arteries
