Non-small cell lung carcinoma

Non-small cell lung carcinoma, abbreviated NSCLC, is a malignant epithelial neoplasm that is not small cell carcinoma of the lung.

It can be understood as a synonym for large cell carcinoma which is umbrella term that includes squamous cell carcinoma of lung and adenocarcinoma of the lung.

General

• Non-small cell lung carcinoma can be considered a waffle diagnosis and as such its use should be limited.
  • It is preferable to be more specific if this is possible, i.e. call adenocarcinoma or squamous cell carcinoma.
• Historically, it was sufficient to differentiate between small cell and non-small cell carcinomas.

Microscopic

Features:

• Large cells with abundant cytoplasm.
• +/-Nucleoli.
• No stippled chromatin.
  • This suggests the large cell variant of small cell carcinoma.

DDx:

• Squamous cell carcinoma of the lung.
• Adenocarcinoma of the lung.
• Small cell carcinoma of the lung.
• Large cell variant of small cell carcinoma of the lung.

IHC

Sloan-Kettering algorithm - Rekhtman et al.:

TTF-1\p63	p63 -ve (0% of cells)	p63 +ve <50% of cells	p63 +ve >=50% of cells
TTF-1 +ve >=50% of cells	Adenocarcinoma	Adenocarcinoma	Adenocarcinoma
TTF-1 +ve <50% of cells	Adenocarcinoma	Adenocarcinoma	Squamous carcinoma
TTF-1 -ve (0% of cells)	Adenocarcinoma	CK5/6 to determine	Squamous carcinoma

See also

• Lung tumours.