Lung Cancer

Question 1

Adenocarcinoma

Answer 1

1. Tumor of glandular origin/mucin production
2. Peripherally located
   Gross morphology: grey hard mass located peripherally w/ a central scar
   Histology: gland formation w/ lumens, mucin production, + thyroid TF-1/mucin staining

Question 2

Bronchoalveolar Carcinoma

Answer 2

Diffuse multinodular carcinoma (hard to distinguish from metastasis) of pneumocyte origin w/ surfactant production
Associated w/ prior lung disease in non-smokers

Question 3

Squamous Cell Carcinoma

Answer 3

Malignant epithelial tumor w/ squamous differentiation (keratin formation & intercellular bridging; smoking
Arise centrally in major bronchi
Produces PTH
Keratin pearls: concentric circles w/ center of acellular eosinophilic keratin

Question 4

Large Cell Carcinoma

Answer 4

Undifferentiated malignant epithelial tumor, bulky

Histology: sheets of large pleomorphic cells w/ large nuclei, prominent nucleoli, frequent mitoses

Question 5

Small Cell Carcinoma

Answer 5

Malignant epithelial tumor of neuroendocrine cells
Arise centrally & extend to adjacent parenchyma, lymph spread, metastasize early
Produces ectopic hormones (ACTH,calcitonin, ADH)
Tx: automatically get systemic chemotherapy

Question 6

Lung Carcinoid

Answer 6

Low grade tumors of endocrine cells
Gross: polypoid mass in bronchi w/ plaque-like growth & extension through the wall
Histology: nests of uniform cells separated by fibrovascular stroma

Question 7

Hamartoma

Answer 7

Most common benign tumor of lung
Usually a solitary lung nodule – “coin lesion” on CXR
Gross: small well circumscribed grey bulging lesion which “shell out” easily, cartilaginous w/ “shiny” cut surface