Lung Tumours 🦋 Flashcards
Most lung tumors are
Carcinomas (95%)
When do carcinomas occur more often
Between 40-70 yrs
What’s the peak incidence for carcinomas
50-60 yrs
What’s the survival rate for carcinomas
5 yr survival rate (5-10%)
What is the etiology and pathogenesis of lung tumors
There is accumulation of genetic abnormalities that transform benign epithelium to neoplastic tissue as well as environmental factors (tobacco smoke)
What is the statistical data on tobacco smoke
- 87% carcinomas occur in active smokers or those who recently stopped
- avg smokers have x10 increased risk of acquiring lung cancer than non smokers
- heavy smokers increase their risk by x60
- there is an association with cancer of mouth, larynx,pharynx,esophagus,pancreas,cervix,kidney,bladder
What is the clinical data on tobacco smoke
- the sequential changes in the respiratory epithelium
- there is linear correlation between extent of exposure and worrisome epithelial changes ie squamous metaplasia-dysplasia-in situation-invasive carcinoma
What are causes of lung cancer
- tobacco smoke
- industrial hazards (high dose ionizing radiation, asbestos)
- air pollution ( ie indoor air pollution such as radon)
- molecular genetics
What are the 2 main categories of lung tumors
- small cell carcinoma
- non-small carcinoma
What are the subdivisions of non-small carcinoma
- squamous cell CA (25-40%)
- adenocarcinoma (25-40%)
- large cell CA (10-15%)
What lung cancer is most common in women and non-smokers
Adenocarcinoma because of increase in number of women smokers
What’s the problem with cigarettes that have to be inhaled more deeply, like those with a filter or low nicotine
Because it exposes more peripheral airways and cells to carcinogens
Which cancer is more metastatic and has a high initial response to chemotherapy
Small cell carcinoma
Which cancer is less metastatic and less responsive to chemotherapy
Non-small cell carcinoma
Which cancers have a strong correlation to smoking
- small cell carcinoma
- squamous cell carcinoma
Which cancer arises more often in/near the hilum, centrally in the lung or from the 1st-3rd bronchi
- small cell carcinoma
- squamous cell carcinoma
Which cancer arises in the periphery of the lung ie alveolar septa or near terminal bronchioles (acinar)
Adenocarcinoma
How does squamous cell carcinoma appear
It’s gray-white and firm to hard
Where does squamous cell CA metastasize
Outside of the thorax late in its development
Squamous cell CA is often found in what gender
Men
How does adenocarcinoma appear
Can differentiate into glandular structure and produce mucin
What is the most aggressive,highly malignant lung tumor that can metastasize widely
Small cell CA
What are the local effects of lung tumor spread
- pneumonia,abscess,lobar collapse (from tumor obstruction of airway)
- lipid pneumonia (from tumor obstruction )
- pleural effusion (from tumor spread into pleura)
- hoarseness (from recurrent laryngeal nerve invasion)
- dysphagia (from esophageal invasion)
- diaphragm paralysis (from phrenic nerve invasion)
- rib destruction ( from chest wall invasion)
- SVC syndrome (from SVC compression by tumor)
- Horner syndrome (from sympathetic ganglia invasion)
- pericarditis, tamponade (from pericardial involvement )
What hormones does the small cell CA secrete that cause paraneoplastic syndromes
- it releases adrenocorticotropic hormone which causes the increased production and release of cortisol from the adrenal cortex resulting in atypical Cushing syndrome with facial edema and cachexia and hypokalemic alkalosis
- it also releases ADH which cause the kidney to retain more water resulting in edema, high blood pressure and hyponatremia
What hormones does the squamous cell Ca secrete that cause paraneoplastic syndrome
-it releases parathyroid hormone which causes the release of calcium by bones into the blood resulting in hypercalcemia, lethargy,abdominal pain, constipation
What hormone can be released by squamous cell CA, small cell CA or adenocarcinoma and cause a paraneoplastic syndrome
Gonadotrophic substances can be releases which cause testicular atrophy and gynecomastia (man boobs)
What tumors can form a pancoast tumor (apical lung Ca)
Adenocarcinoma and squamous cell CA
What damage can a pancoast tumor cause
- It invades/ compresses on the thoracic inlet,brachial plexus and cervical sympathetic nerves which can lead to Horner syndrome (enophthalmos, ptosis,mitosis,anhydrosis-where you can’t sweat)
- Can cause severe pain in ulnar nerve (pancoast syndrome)
What is a pleural tumor
- it’s a tumor that produces serous fluid
- it’s normally a result of metastasis
- it arises from primary CA of lungs, breast,ovary
What is malignant mesothelioma
- it arises from pleura
- it is asbestos related
- it has a long latent period (25-50yrs)
- it covers lung, invades thoracic cavity and structures ie pericardium ,infiltrates interlobar fissure
What are the symptoms of malignant mesothelioma
- chest pain
- dyspnea
- recurrent pleural effusions
