Pulmonary Pathology III

Question 1

Most common lung cancers

Answer 1

Adenocarcinoma (38%)
Squamous cell carcinoma (20%)
Small cell (neuroendocrine) carcinoma (14%)
Large cell carcinoma (3%)

Question 2

What is the progression of normal lung tissue to adenocarcinoma?

Answer 2

1. Normal
2. AAH (atypical adenomatous hyperplasia)
3. AIS (adenocarcinoma in situ)
4. Adenocarcinoma

Question 3

Atypical adenomatous hyperplasia (AAH) size:

Histological appearance:

Answer 3

<5 mm

Dysplastic pneumocytes present along alveoli w/ some interstitial fibrosis. Leads to AIS.

Question 4

Adenocarcinoma in situ (AIS) size:

Histological appearance:

Answer 4

<3 cm

Dysplastic pneumocytes confluently growing along along alveoli. Follows AAH.

Question 5

Pulmonary adenocarcinoma shows which structures as malignant?

What does it arise from?

Answer 5

Glands invade the surrounding lung tissue.

Can arise from precursors or develop de novo.

Question 6

What does Mucinous Adenocarcinoma mimic?

Answer 6

Pneumonia

Question 7

What is the progression of squamous carcinoma?

Answer 7

1. Normal epithelium
2. Squamous metaplasia
3. Squamous carcinoma in situ
4. Invasive squamous carcinoma

Question 8

What people are more likely to get squamous carcinoma?

Answer 8

More common in men, strong correlation w/ smoking.

Question 9

Where does squamous carcinoma tend to begin?

Answer 9

Centrally

Question 10

What key histological characteristic suggests squamous carcinoma?

Answer 10

Keratin pearls and orange cytoplasm

Question 11

Small cell (neuroendocrine) carcinoma

What is the grade of the malignancy?

Answer 11

Almost always associated w/ smoking.
High rate of mets.

Neuroendocrine carcinoma grade 3.

Question 12

What are the treatment recommendations for Small cell (neuroendocrine) carcinoma?

Answer 12

Surgery not recommended if metastatic to LNs.

Specific chemo is available. Good response to chemo and radiation, but there is a high rate of recurrence.

Question 13

What molecular markers can be used to identify Adenocarcinoma?

Answer 13

EGFR
ALK
PDL-1

Question 14

What paraneoplastic syndrome is associated w/ squamous carcinoma?

Answer 14

Hypercalcemia: PTH-related peptide

Question 15

What paraneoplastic syndromes are associated w/ Small cell carcinoma?

Answer 15

SIADH - too much ADH secretion.

Cushing’s syndrome - secretion of ACTH.

Question 16

Why might Horner’s syndrome develop in a patient with a pulmonary malignancy?

SX of Horner’s syndrome

Answer 16

In superior lung cancers where they can affect the cervical sympathetic plexus.

Enophthalmos - sunken eye ball
Ptosis - drooping of eyelid
Miosis - small pupil
Anhidrosis - no sweating on IL side of face

Question 17

What kind of tumor is Diffuse pulmonary neuroendocrine cell hyperplasia (DIPNECH)?

What detects them?

What is their size?

Answer 17

Neuroendocrine tumor.

High-res CT.

<5 mm (“tumorlets”).

Question 18

What kind of tumor is a carcinoid tumor?

What makes these tumors important?

What is their size?

Answer 18

Neuroendocrine tumor.

5 mm or bigger.

Capable of metastasizing.

Question 19

How are carcinoid tumors classified?

Answer 19

Indolent - neuroendocrine carcinoma grade 1.

Question 20

Atypical carcinoid tumor is classified as:

What is the likelihood of mets?

What are the chances of survival?

Answer 20

Neuroendocrine tumor grade 2.

Increased rate of mets.

Lower survival rate (but better than SCC).

Question 21

How does atypical carcinoid tumor and carcinoid tumor differ?

Answer 21

Atypical carcinoid tumors have:

Increased mitotic activity
Necrosis
Disorderly growth

Question 22

What are the SX of carcinoid syndrome?

Answer 22

Flushing, diarrhea, cyanosis.

Question 23

5-year survival rates for:

Carcinoid tumors (NE carcinoma grade 1)

Atypical carcinoid tumors (NE carcinoma grade 2)

Small cell carcinoma tumors (NE carcinoma grade 3)

Answer 23

Carcinoid tumors (NE carcinoma grade 1) - 95%

Atypical carcinoid tumors (NE carcinoma grade 2) - 70%

Small cell carcinoma tumors (NE carcinoma grade 3) - 5%

Question 24

What makes up a pulmonary hamartoma?

What is it called when seen on CT?

Answer 24

Fibrous tissue w/ benign glandular epithelium around hyaline cartilage.

“Coin” lesion.

Question 25

Lymphangioleiomyomatosis (LAM) occurs in: What LoF is it associated with? What is the pathogenesis? What type of cells are found in the BX? What else does it present w/ often?

Answer 25

Young women. TSC2. Proliferation of cells creating cystic spaces. Modified SM cells, which are positive for melanoma markers (HMB-45). Perivascular epithelioid cells. Pneumothorax, due to "popping" of the cystic space.

Question 26

What is the most common cause of transudative (liquid) pleural effusions?

Answer 26

Heart failure

Question 27

What are the most common causes of exudative (inflammatory) pleural effusions?

Answer 27

Infection | Malignancy

Question 28

What makes up an empyema? What structures does it almost always create? What does the fluid look like?

Answer 28

An inflammatory exudate w/ accumulation of pus, usually from a bacterial infection. Loculations - web-like traps for fluid. Thick, yellow. Will have neutrophils and bacteria.

Question 29

Which patients are at greatest risk for primary (idiopathic) pneumothorax? How?

Answer 29

Young pts. via rupture of subpleural blebs.

Question 30

What causes a tension pneumothorax?

Answer 30

Injury to chest wall resulting in one-way valve allowing air into the pleural space, but not out. It is expansion of the chest wall, but not necessarily the lungs, that is responsible for respiration. In a closed system, air is a space-occupying lesion.

Question 31

What can cause a secondary pneumothorax?

Answer 31

``` Cystic infections Cystic tumors Rupture of blebs Trauma Positive-pressure ventilation ```

Question 32

What is the pressure differences in the pleural cavity compared to atmospheric in primary vs. tension pneumothorax?

Answer 32

Primary - pleural cavity pressure < atm. Tension - pleural cavity pressure > atm.

Question 33

Solitary fibrous tumor are what kind of tumors? Where are they located? What is its shape?

Answer 33

Benign (when small and pedunculated) tumors of the pleura. Larger ones may behave like sarcomas. CIrcumscribed.

Question 34

What are 3 variants of Mesothelioma? What is a stain that can help distinguish it from Adenocarcinoma?

Answer 34

Epithelioid, Sarcomatoid, Mixed. Calretinin.

Question 35

How is Mesothelioma treated? Is it responsive to chemo/radiation? What is the prognosis?

Answer 35

Difficult to treat, as it cannot be excised surgically. Limited responsiveness to chemo/radiation. Most pts. will not live after 2 yrs.

Question 36

Which malignancies develop proximally, in various locations, and peripherally?

Answer 36

Proximal - squamous cell carcinoma Various - small-cell NE carcinoma Peripherally - adenocarcinoma

Question 37

Which cancer exhibits some degree of the 2-hit theory? What other lung cancer can it exist with?

Answer 37

Small-cell NE carcinoma: Rb goes first, then p53. Can exist w/ squamous cell carcinoma.

Question 38

What should be considered if a pt. has pneumonia-like SX, but does not respond to any therapy?

Answer 38

Mucinous adenocarcinoma

Question 39

How is mucinous adenocarcinoma differentiated from AIS?

Answer 39

Size. Mucinous adenocarcinoma > 3 cm.

Question 40

What is the course of action once a DX of small-cell NE carcinoma is made?

Answer 40

PET CT due to high likelihood of mets.

Question 41

If the effusion is bloody, what would be a concern? If effusion is pale-yellow, what is a likely DX? If effusion is white and chalky, what is a concern?

Answer 41

Metastases HF, a transudative effusion A neoplasm that blocks thoracic duct. Or post-op where the thoracic duct is clipped.