Pulmonary Pathology Part 5

Question 1

What are some epidemiology/risk factors for lung cancer?

Answer 1

• Smoking
• Radon
• Asbestos
• Environmental tobacco exposure
• Genetics
• Other lung diseases
• Prior radiation

Question 2

What is the progression to lung carcinoma of alveolar/bronchial epithelial cells?

Answer 2

• Kras or B-catenin mutation leading to atypical adenomatous hyperplasia
• The adenomatous hyperplasia leads to primary adenocarcinoma

Question 3

What is the progression to lung carcinoma of bronchial epithelial cells?

Answer 3

• Chr 3p LOH leading to squamous dysplasia

- This ends in primary squamous cell carcinoma

Question 4

What is the progression to lung carcinoma of epithelial cells with neuroendocrine features?

Answer 4

• Chr 3p LOH which causes a p53 inactivation

- Ends in primary small cell carcinoma

Question 5

What is the most predominant type of carcinoma? Why?

Answer 5

• Adenocarcinoma due to much more of the lung tissue being alveolar parenchyma

Question 6

What is the progression of pulmonary adenocarcinoma?

Answer 6

1. Normal tissue
2. Atypical adenomatous hyperplasia
3. Adenocarcinoma in Situ
4. Adenocarcinoma

Question 7

What is atypical adenomatous hyperplasia?

Answer 7

• <5mm

- Dysplastic pneumocytes present along alveoli with some interstitial fibrosis

Question 8

What is adenocarcinoma in situ?

Answer 8

• Formerly bronchioloalveolar carcinoma (BAC)
• <3cm
• Dysplastic pneumocytes confluently growing along alveoli

Question 9

What is pulmonary adenocarcinoma?

Answer 9

• Can arise from precursors or develop de novo
• Most common lung malignancy in smokers and non-smokers
• Histology shows malignant glands invading the lung tissue

Question 10

What does gland forming adenocarcinoma stain positive?

Answer 10

• TTF-1 (thyroid transcription factor 1)

Question 11

What can mucinous adenocarcinoma mimic? How is this a problem?

Answer 11

• Mimics pneumonia

- A problem because a non-oncologist may assume that it is pneumonia and treat that

Question 12

What is a key aspect of squamous carcinoma on histology?

Answer 12

• Keratin pearls

Question 13

What does orange cytoplasm mean on cytology?

Answer 13

• Keratin

Question 14

What is squamous carcinoma?

Answer 14

• More common in men
• Strong association with smoking
• Occurs centrally

Question 15

What is the TNM staging mnemonic mean?

Answer 15

• T is the tumor size
• N is the lymph node involvement
• M is the metastasis to other body parts

Question 16

What is small cell “neuroendocrine” carcinoma?

Answer 16

• Almost always associated with smoking
• High rate of metastasis
• Important to identify for purposes of treatment

Question 17

When is surgical excision not recommended for small cell “neuroendocrine” carcinomas?

Answer 17

• If metastatic to LN

Question 18

What is the treatment for small cell carcinomas?

Answer 18

• Specific chemotherapy due to its responsiveness

Question 19

What molecular testing do you do for adenocarcincomas?

Answer 19

• EGFR
• ALK
• PDL-1

Question 20

What do you use to treat adenocarcinoma if the EGFR mutation is positive?

Answer 20

• Erlotinib

- Gefitinib

Question 21

What do you use to treat adenocarcinoma if there is ALK rearrangment?

Answer 21

• Crizotinib

Question 22

What do you use to treat adenocarcinoma if there is a problem with the PD-1/PDL-1?

Answer 22

• Pembrolizumab

Question 23

What do you use to treat adenocarcinoma if there is a problem with CTLA-4?

Answer 23

• Ipilimumab

Question 24

What don’t you use to treat squamous carcinoma?

Answer 24

• Don’t use VEGF inhibitors due to risk of bleeding

Question 25

What do you use to treat small cell carcinoma?

Answer 25

- Specific chemotherapeutic regimens

Question 26

What is can help diagnose squamous carcinoma?

Answer 26

- Hypercalcemia: PTH-related peptide

Question 27

What can help diagnose small cell cardinoma?

Answer 27

- SIADH (inappropriate secretion of ADH) | - Cushing's syndrome (secretion of ACTH)

Question 28

How can a lung carcinoma cause horner's syndrome?

Answer 28

- Carcinoma in the upper lobe can disrupt the sympathetic pathway

Question 29

What is DIPNECH?

Answer 29

- Diffuse interstitial pulmonary neuroendocrine cell hyperplasia - High-resolution CT scan detects these nodules - Very small, less than 5 mm

Question 30

What is a carcinoid tumor?

Answer 30

- 5mm or larger - These can mestatize - Indolent - Neuroendocrine carcinoma grade 1

Question 31

What is an atypical carcinoid tumor?

Answer 31

- Neuroendocrine carcinoma grade 2 - Increased mitotic activity - Necrosis - Disordered growth - Increased rate of metastasis - Lower survival

Question 32

What is carcinoid syndrome?

Answer 32

- Flushing - Diarrhea - Cyanosis

Question 33

What is the 5 year survival rate for the different neuroendocrine tumors?

Answer 33

- Carcinoid tumors: 95% - Atypical carcinoid tumors: 70% - Small cell carcinoma: 5%

Question 34

What is a lymphangioleiomyomatosis (LAM)?

Answer 34

- Proliferation of cells creating cystic spaces - Modified smooth muscle cells - Positive for melanoma markers like HMB-45 - Perivascular epithelioid cells (PEC-oma)

Question 35

Who typically has LAM?

Answer 35

- Young women

Question 36

What is LAM associated with?

Answer 36

- Loss of function of tumor suppressor TSC2

Question 37

What are some major causes of pleural effusion?

Answer 37

- Heart failure - Infection - Malignancy

Question 38

What is the cause of a bloody pleural effusion?

Answer 38

- Malignancy

Question 39

What is the cause of a milky chylous pleural effusion?

Answer 39

- Obstruction of the thoracic duct

Question 40

What is the cause of a serous pleural effusion?

Answer 40

- Heart failure

Question 41

What is empyema?

Answer 41

- Inflammatory exudate with accumulation of pus in the pleural space - Notorious for creating loculations (web like traps for fluid)

Question 42

What typically causes empyema?

Answer 42

- Bacterial infection

Question 43

What does the fluid look like in empyema?

Answer 43

- Fluid will be thick, yello; smears of fluid will show neutrophils and often bacteria

Question 44

What is a cause of a spontaneous pneumothorax?

Answer 44

- Rupture of subpleural blebs (young patients)

Question 45

What are some causes of a secondary pneumothorax?

Answer 45

- Cystic infection - Cystic tumors - Positive pressure ventilation - Trauma

Question 46

What causes a tension pneumothorax?

Answer 46

- Injury to the chest wall resulting in a one-way valve allowing air into the pleural space, but not out

Question 47

What does a tension pneumothorax look like?

Answer 47

- Air is pulled to where it is easier | - Trachea will deviate away from lesion

Question 48

What is a benign pleural tumor?

Answer 48

- Solitary fibrous tumor

Question 49

What is a malignant pleural tumor?

Answer 49

- Mesothelioma

Question 50

What are some characteristics of a solitary fibrous tumor?

Answer 50

- Benign when small and pedunculated | - Larger ones may behave like sarcoma

Question 51

What is a solitary fibrous tumor?

Answer 51

- A circumscribed pleural-based mass | - Easy to excised due to being pedunculated

Question 52

What is mesothelioma?

Answer 52

- Associated with asbestos exposure - May occur decades after exposure - Lifetime exposure risk is as high as 10%

Question 53

What are the different variants of mesothelioma?

Answer 53

- Epithelioid - Sarcomatoid - Mixed

Question 54

How is mesothelioma treated?

Answer 54

- Not easily - Hard to excise surgically - Responsiveness to chemotherapy and radiation is limited

Question 55

What is the mortality of mesotehlioma?

Answer 55

- Most will not live 2 years after diagnosis