20475212

A 44-year-old woman with lower back pain

A large mass in right middle lung zone

A large mass in right lower lobe, superior segment

Gross image; A large ovoid firm mass, white tan in color, multifocal small necrosis

Close view of H&E slide

Close view of H&E slide

Lower power view

Spindle cell tumor

Adenocarcinoma

Adenocarcinoma + Spindle cell carcinoma

Adenocarcinoma + Spindle cell carcinoma

Immunohistochemical staining

Pleomorphic carcinoma• A poorly differentiated non-small cell carcinoma,

namely squamous cell carcinoma, adenocarcinoma or large cell carcinoma containing spindle cell and/or giant cells or, a carcinoma consisting only of spindle and giant cells.

• The spindle or giant cell component should comprise at least 10% of the tumor and while the presence of adenocarcinoma or squamous cell carcinoma should be documented, foci of large cell carcinoma need not be mentioned.