Respiratory- CA, CF, Failure

Question 1

Describe the Characteristics of Lung CA

character and spread

Answer 1

• 1* and 2*
• major cause of death
• aggressive, invasive, metastatic
• spreads to bone, liver and brain

Question 2

Describe 4 types of Lung CA and incidence

Answer 2

o  Adenocarcinomas (~30%)
o  Squamous cell carcinoma (30%)
 (Non-Small Cell Lung Cancer)
o  Large cell carcinoma (~12%)
o  Small cell carcinoma (~22%) SCLC

Question 3

Etiology of lung CA (risks)

Answer 3

• Smoking (>80%)
• Toxins (eg asbestos)
• Genetic predisposition
(…HLA on 6 plus other familial connections)

Question 4

Describe Adenocarcinoma

Answer 4

Peripheral origin
(Alveoli or bronchioles)

Common in women (not clear why) and in non smoker (not clear why)

Question 5

Describe squamous cell carcinoma

Answer 5

o Arises in the central bronchi (hilum)
o Spreads to hilar nodes
o More common in men (no clear reason)
o Growth can effect external structures like the heart.

Question 6

Describe Large cell carcinoma

Answer 6

o Peripheral origin
(Alveoli and bronchioles)
o Large and undifferentiated cells
o Early metastasis (Poor prognosis)

Question 7

Describe Small cell carcinoma

Answer 7

o	99% in smokers
o	Aggressive, invasive, early metastasis (esp brain)
o	Small, oval cells
o	Often metastasized by Dx 
o	Non-resectable
o	Radiosensitive

plus paraneoplastic

Question 8

Which type of CA is related to paraneoplastic syndrome?

Answer 8

Small cell carcinoma

Paraneoplastic refers to ectopic tumors we spoke of in endocrine

(eg SIADH, Cushings – cortico and ACTH excess)

Question 9

MNFTS of lung CA

Answer 9

• Based on type and location (eg. Central or peripheral- bronchi, lungs, heart)
• Based on extent and metastasis
• Paraneoplastic syndromes

• For all types/locations
o Hemoptysis
o Pain

Question 10

What sort of MNFTS are dependent of location of tumor in lung CA

Answer 10

If central -> impairs ventilation -> coughing, wheezing, dyspnea

Tumors on left side will result in cardiac MNFTS

Question 11

Dx of Lung CA

Answer 11

• Hx, Px, US, CXR, MRI
• Bronchoscopy, needle biopsy
• Cytology (sputum or bronchial wash)

No adequate screen to pick up early lung cancer

Question 12

Tx for Lung CA

Answer 12

• NSCLC: Sx, radiation and chemo
• SCLC: chemo and radiation
• Poor prognosis

Question 13

What is Cystic Fibrosis

Answer 13

Hereditary exocrine disease

Defective Cl- channel in cell membrane leading to hypersecretion (or at least build up) of fluid

Question 14

What systems does cystic fibrosis Affect?

Answer 14

Exocrine cells!

GI tract (pancreas, etc), reprod tract and resp system

Question 15

Etiology of Cystic Fibrosis

Answer 15

•CFTR (cystic fibrosis transmembrane regulator) gene on Chr 7

(CFTR is the protein)

Autosomal recessive

Question 16

Patho of Cystic Fibrosis

Answer 16

CFTR gene mutation leads to defective Cl channel on epith cells of resp tract (and elsewhere)

• Mutation makes cell impermeable to Cl-
leading to Impaired Cl- transport across cell membrane

• Abnormal secretion and also inc concentration of Cl- on outside of epithelial membrane
• High Cl- conc pulls h20 and Na from mucous in the resp. lumen
• Mucous becomes thick and viscous cannot be moved by cilia -> dec cilliary fx -> plugs airway -> dec fx (i.e gas exchange)
• Mucous is great spot for bact growth (recurrent bacterial infection.
• > 90% die from severe pulmonary disease

Question 17

Dx of cystic Fibrosis

Answer 17

• Sweat test
• CF in a sibling
• Newborn (trypsinogen) = a precursor for trypsin
• GI and Resp tract MNFTS

Question 18

Tx of Cystic Fibrosis?

Answer 18

• No cure, will succumb to respiratory failure (inflm and inf)

• DNAase (reduce mucus stickiness)
o DNA released by dead cells in mucus, help reduce strands making it easier to mobilize

• Control infection (they tend to be major and persistent)
o Prophylaxis, and abx tx, not easy
• Diet mod and pancreatic E supplement
• Anti inflm and gamma globulins indications)

Question 19

What is Respiratory Failure?

Answer 19

•No gaseous exchange

o Hypoxemia and Hypercapnea

Question 20

Tx of Respiratory Failure

Answer 20

• Restore gas exchange eg:
   o 02
   o Bronchodilators ?? (based on cause)
   o Mech ventilation`
   o Abx?? (based on cause)

Question 21

MNFTS of Respiratory Failure

Answer 21

Hypercapnia ( over 45mmHG)
Hypoxemia (under 60mmHG)
Resp Acidosis
MNFTS of Cause