Pulmonary blastoma

Pulmonary blastoma is a very rare tumour of the lung. These tumours are often lumped into the pulmonary sarcomatoid carcinomas group.

General

• Very rare ~ 100 cases in the literature.
• Abysmal prognosis - 5-year survival ~ 15%.
• Typical patient <20 years old.
  • Adults usu. in 40s.
• Resemble immature lung tissue.

Classification

Traditionally subdivided into:

• Well-differentiated fetal adenocarcinoma (WDFA).
• Classic biphasic pulmonary blastoma (CBPB).
• Pleuropulmonary blastoma.
  • Now considered a separate entity.

Gross

• Lung tumour.

Microscopic

Features:

• Epithelial component.
• Mesenchymal component.
  • Small round cells.

DDx:

• Small round cell tumours.

Images

• Pulmonary blastoma (nih.gov).
• Pulmonary blastoma (nih.gov).
• Fetal type adenocarcinoma (upmc.edu).
• Pulmonary blastoma (surgicalpathologyatlas.com).
• Pleuropulmonary blastoma (ppbregistry.org).
• Pleuropulmonary blastoma (webpathology.com).

IHC

Features:

• TTF-1 +ve.
• S-100 -ve.
• Vimentin -ve.^{[citation needed]}
• EMA -ve.

See also

• Small cell carcinoma.
• Pulmonary hamartoma.