Pulmonary Carcinoid Tumors and Other Primary Lung Tumors

Question 1

WHO classification of carcinoid tumors

Answer 1

Typical (< 2 mitotic figures/hpf, no necrosis)

Atypical (2-10 mitotic figures/hpf, tissue necrosis, or architectural disruption)

Question 2

Prevelence of typical vs atypical carcinoid tumors

Answer 2

Typical: 75-80% of tumors

Atypical: 15-20% of tumors

Question 3

According to WHO carcinoid tumors are part of the histologic spectrum of neuroendocrine tumors, including…

Answer 3

• Typical carcinoid (low grade)
• Atypical carcinoid (intermediate grade)
• Large cell neuroendcrine (high grade)
• SCLC (high grade)

Question 4

Demographic characteristics of carcinoid tumor presentation

Answer 4

Bimodal age distribution (peaks at 35 and 55 years of age)

Question 5

Presentation of pulmonary carcinoid

Answer 5

• Asymptomatic (1/3 pts)
• recurrent PNA
• cough
• hemoptysis

Question 6

Ectopic hormones secreted by carcinoid tumors

Answer 6

• 5-hydroxytryptophan
• ACTH
• vasopressin
• insulin

Question 7

Anatomic characteristics of carcinoid tumors

Answer 7

• Central location
  
  • Typical (70%)
  • Atypical (50%)
• Lobar or sublobar bronchus (75%)

Question 8

CT findings of carcinoid tumors

Answer 8

• Peripheral tumors:
  
  • smooth, round, homogenous appearance
• Central tumors:
  
  • obvious airway component, post-obstructive atelectasis or pneumonitis

Question 9

Other diagnostic studies used in w/u of carcinoid

Answer 9

• PET scan
• Octreotide scan
• Bronchoscopy (with biopsy)
  
  • central tumors
• CT guided FNA biopsy:
  
  • peripheral tumors

Question 10

Success of preoperative diagnosis of carcinoid

Answer 10

70-80%

Question 11

Most peripheral and central tumors without evidence of nodal disease

Answer 11

Typical carcinoid tumors

(no further eval needed prior to resection)

Question 12

Distribution of atypical carcinoid tumors with central location and cN1 or cN2 disease

Answer 12

Cenral location (50%)

Peripheral location (50-70%)

*need thourough staging prior to resection (including mediastinoscopy)

Question 13

Surgical treatment principles for carcinoid

Answer 13

• R0 resection (limited resection is acceptable)
• Medistinoscopy with LN bx shoud be performed:
  
  • Clinical nodal diseaes
  • Atypical carcinoid histology

Question 14

Indication for neoadjuvant/adjuvant chemotherapy for carcinoid

Answer 14

N2 disease

Question 15

Surgical option for carcinoid tumors in patients unable to tolerate parenchymal resection

Answer 15

Endobronchial resection

(negative margin important >> high chance of local recurrence)

Question 16

Definiton and characteristics of carcinoid tumorlets

Answer 16

Carcinoid tumors < 5 mm in diameter

• 10% of patients with other primary carcinoid tumor or other types of NSCLC
• should no be staged as metastatic disease
• treatment should be based on primary lesion

Question 17

TOC for metastaic or unresectable carcinoid

Answer 17

Chemotherapy

Reponse rates 20-40%

30% will progress while receiving chemotherapy

Question 18

Duration of postoperative followup for carcinoid

Answer 18

20 years due to indolent nature of disease

Question 19

Tumor of trachea or mainstem bronchus usually detected when symptomatic with significant obstructive component

Answer 19

Adenoid cystic carcinoma

Question 20

Submucosal extension beyond gross intraluminal tumor characteristic of these tumors

Answer 20

Adenoid cystic carcinoma

Intraoperative frozen section thus essential for R0 resection

Question 21

Other salivary gland-type tumors

Answer 21

Mucoepidermoid

Acinic cell carcinoma

Question 22

Most common benign lung tumors

Answer 22

• Hamartoma
• Inflammatory pseudotumor
• Sclerosing hemangioma
• Bronchogenic cyst
• Leiomyoma
• Adenoma
• Papilloma and soft tissue tumors