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ICD-O-3 Site Codes

Related Adjectives

Lung = pneumo-, pulmono-, broncho-, bronchiolo-, alveolar, hilar, Breathing = -pnea

ICD-O-2/3 Term
C34.0 Main bronchus
C34.1 Upper lobe, lung
C34.2 Middle lobe, lung (right lung only)
C34.3 Lower lobe, lung
C34.8 Overlapping lesion of lung
C34.9 Lung, NOS
C33.9 Trachea, NOS

Prior to the Second Edition of ICD-O, trachea and lung had the same ICD-O code. With the advent of ICD-O-2, trachea has a separate code (C33.9) from lung (C34._).

The ICD-O four-digit sub sites of C33.9 through C34.9 are considered part of a single primary site. Since lung is a paired organ, laterality must be coded.

Lung Anatomy (Showing ICD-O-2/3 Codes)

Illustration of the anatomy of the lung.