Visceral and Parietal Pleural Invasion is defined as invasion beyond the elastic layer or to the surface of the visceral pleura.

Visceral and Parietal Pleural Invasion (previously called "pleural/elastic layer invasion (PL)") is a Registry Data Collection Variable for AJCC. This data item was previously collected for Lung, SSF# 2.

0	No evidence of visceral pleural invasion identified Tumor does not completely traverse the elastic layer of the pleura Stated as PL0
1	Invasion of visceral elastic layer Not beyond visceral pleural Stated as PL1
2	Invasion outside surface of the visceral pleura Invasion through outer surface of the visceral pleura Stated as PL2
3	Tumor invades into or through the parietal pleura OR chest wall Stated as PL3
4	Invasion of visceral pleura present, NOS; not stated if PL1 or PL2
6	Tumor extends to pleura, NOS; not stated if visceral or parietal
8	Not applicable: Information not collected for this case (If this item is required by your standard setter, use of code 8 will result in an edit error.)
9	Not documented in medical record No surgical resection of primary site is performed Visceral Pleural Invasion not assessed or unknown if assessed or cannot be determined

Each Site-Specific Data Item (SSDI) applies only to selected primary sites, histologies, and years of diagnosis. Depending on applicability and standard-setter requirements, SSDIs may be left blank.