Lung Cancer Flashcards
Paraneoplastic syndrome of SMALL CELL LUNG CARCINOMA
1- SIADH - hyponatremia
2- ACTH oversecretion causing Cushings
3- Lembort Eaton syndrome - neuromuscular weakness
Paraneoplastic syndrome of
Squamous cell carcinoma
1- parathyroid hormone related peptides causing hyperparathyroidism and
hypercalcemia
2- TSH like peptides causing hyperthyroidism
3- lung cancer related osteoarthropathy
Paraneoplastic syndrome of Adenocarcinoma
1- Gynecomastia
2- cancer related osteoArthropathy
3- rare Limbic Encephalitis
Exposure of beryllium in which industry
Dental supples - think!!
Prosthetics - knee??
Aerospace
Ceramics - cookery??
Heavy metal : falls in lower zones of lungs
Exposure of asbestos
Builder - is not coal
Ship industry - is not coal
Asbestos exposure
All asbestos exposure does NOT mean asbestosis.
Asbestos exposure can manifest in 3 forms
1- pleural plaques - benign
2- asbestosis = fibrosis
3- mesothilioma = pleural membrane cancer (outer covering lining the lung and chest wall)
Key points:
Pleural plaques ≠ cancer risk. They are marker lesions indicating past asbestos exposure but are not pre-malignant.
• Asbestosis (fibrosis) and mesothelioma are the real risks.
• Mesothelioma can occur even with minimal asbestos exposure.
• Crocidolite (blue asbestos) is the most dangerous type, with the highest malignancy risk.
• Severity of asbestosis (lung fibrosis) depends on total exposure duration.
Behavior of Adenocarcinoma
The correct answer is adenocarcinoma. This is a type of cancer that is not necessarily associated with smoking and as our patient is a non-smoker this is the most likely answer. Lung adenocarcinomas can present as primary lung cancers or as secondaries from adenocarcinomas elsewhere in the body.
Behaviour of Squamous cell carcinoma
Squamous cell lung cancers are strongly associated with smoking and therefore very unlikely in our patient. They can cavitate and sometimes appear as cavitating lesions on chest x-ray. In addition, they are associated with hypercalcemia.
Behavior of small cell lung carcinoma
Small cell carcinomas account for about 20% of lung cancers. They are the most aggressive type of lung cancer and have usually metastasized by the time of diagnosis. The CT report for our patient does not suggest any metastases. Because of this surgery is very rarely an option but they can be very chemosensitive. The are also associated with hyponatraemia.
Cushing syndrome in lung cancer
hypertension,
proximal muscle weakness, hyperglycaemia
hypokalaemia -
are recognised features of Cushing’s syndrome
Notable that patients with this phenomenon do not tend to present with some other classical cushingoid features such as moon facies and buffalo hump as hypercortisolism occurs fairly rapidl
Metastasis on lung - how it appears on CXR
Cavitation - squamous cell carcinoma (smoking)
Calcification is seen with osteosarcomas and chondrosarcomas (bones = calcium) as well as metastases from papillary thyroid carcinoma. (Close to Parathyroid gland = calcium)
Adenocarcinoma metastases spread along the walls of alveoli, instead of destroying the lung parenchyma, resulting in consolidation like that seen with pneumonia.
Haemorrhagic pulmonary metastases occur with choriocarcinoma and angiosarcoma. (Through vasculature)
A miliary pattern of metastases (like bajra) or cannonball pattern like golf balls across lungs, (white on cxr) is visualised with renal cell carcinoma and malignant melanoma because they have hematogenous spread - aggressive - diffusely spreads across lungs
Exposure of which substance is not related to Lung CA
Coal
Behavior of Carcinoid tumor
Carcinoid tumors are a subtype of neuroendocrine tumor and behave differently from typical lung cancers like small cell or non-small cell lung cancer. They tend to grow more slowly and can produce hormones that cause two distinct syndromes 1- carcinoid syndrome 2- Cushing’s syndrome
Difference between pulmonary and GI Carcinoid tumor
Normally, substances like serotonin released by a gastrointestinal carcinoid tumor are filtered out by the liver before they can cause carcinoid syndrome.
This means the liver breaks them down, preventing them from entering the general circulation in significant amounts.
However, if the carcinoid tumor is located in the lungs or if GI carcnoid tumor has metastasized to the liver, the secreted hormones enter the bloodstream directly without being filtered out.
This “bypass” of liver metabolism allows the hormones to circulate and cause the systemic symptoms known as carcinoid syndrome
pulmonary carcinoid tumors more commonly cause symptoms related to ACTH production (like Cushing’s syndrome) or serotonin (like carcinoid syndrome).
GI carcinoid tumors are more likely to produce a variety of hormones depending on their location.
Gastrin: Tumors that produce gastrin are often found in the gastrointestinal tract and can lead to Zollinger-Ellison syndrome, which causes excessive stomach acid and peptic ulcers.
• Insulin: Insulin-producing tumors, known as insulinomas, are usually found in the pancreas. They can cause hypoglycemia due to excess insulin secretion.
• Thyroid and parathyroid hormones: These are less commonly associated with typical carcinoid tumors. However, some neuroendocrine tumors, particularly those in the pancreas or other parts of the digestive tract, can produce a range of hormones, leading to varied clinical presentations.
What is produced by carcinoid tumors
Carcinoid tumors can release hormones , important ones to remember are serotonin and ACTH. When a tumor in the lungs secretes ACTH, it can cause Cushing’s syndrome, which leads to symptoms like weight gain, high blood pressure, and skin changes.
When it secretes serotonin, it can cause carcinoid syndrome
What is carcinoid syndrome (different from carcinoid tumor)
Carcinoid syndrome is primarily due to the secretion of serotonin, and to a lesser extent, other substances like histamine and bradykinin.
These substances cause the hallmark symptoms of carcinoid syndrome, which include
1- skin flushing,
2- diarrhea and abdominal cramping
3- wheezing.
It’s important to note that these symptoms typically occur when the tumor’s secretions mentioned above bypass liver metabolism (like with liver metastases in GI tumor or a primary lung location).
Things to remember about carcinoid tumors!
Carcinoid tumors can cause systemic effects due to hormone secretion.
The key points to remember are:
1. Hormone secretion: Carcinoid tumors secrete serotonin, histamine, or ACTH, leading to specific syndromes.
2. Carcinoid syndrome: This includes symptoms like flushing, diarrhea, and wheezing, typically when the tumor metastasizes to the liver or releases hormones into the bloodstream. 3. Cushing’s syndrome: If the tumor secretes ACTH, it can lead to Cushing’s syndrome, causing weight gain, high blood pressure, and other features of hypercortisolism. 4. Location and behavior: Carcinoid tumors can occur in the lungs or the gastrointestinal tract. They are usually slow-growing but can cause significant symptoms due to hormone release. They can release some different hormones depending on location (thyroid, parathyroid, gastrin, insulin) and some are common for all carcinoid tumors (serotonin/histamine/bradykinin and ACTH) - although carcinoid syndrome is more common in pulmonary location as it bypasses the liver from the get going.
