CS Extension

Notes

**Note 1**: This AJCC staging system applies only to pleural mesotheliomas. Peritoneal and pericardial mesotheliomas are not TNM staged. **Note 2**: Pleural effusion does not affect the coding of the CS Extension field, but is coded in CS Site-Specific Factor 1.

Code	Description	AJCC 7 T	AJCC 6 T	Summary Stage 1977 T	Summary Stage 2000 T
100	OBSOLETE DATA CONVERTED V0200 See code 160 Invasive tumor (mesothelioma) confined to pleura, NOS	ERROR:	ERROR:	ERROR:	ERROR:
120	Ipsilateral parietal pleura, including mediastinal or diaphragmatic pleura, WITHOUT involvement of visceral pleura Stated as T1a with no other information on extension	T1a	T1a	Pleural Effusion Extension	Pleural Effusion Extension
140	Ipsilateral parietal pleura, including mediastinal or diaphragmatic pleura, WITH focal involvement of visceral pleura Stated as T1b with no other information on extension	T1b	T1b	Pleural Effusion Extension	Pleural Effusion Extension
160	Invasive tumor (mesothelioma) confined to pleura, NOS Ipsilateral parietal pleura, including mediastinal or diaphragmatic pleura, involvement of visceral pleura not stated	T1NOS	T1NOS	Pleural Effusion Extension	Pleural Effusion Extension
170	Stated as T1 [NOS] with no other information on extension	T1NOS	T1NOS	Pleural Effusion Extension	Pleural Effusion Extension
200	Ipsilateral pleura WITH nodule(s) beneath visceral pleural surface Ipsilateral pleural surface with confluent visceral pleural tumor (including fissure)	T2	T2	Pleural Effusion Extension	Pleural Effusion Extension
300	OBSOLETE DATA RETAINED AND REVIEWED V0203 See codes 170, 305 Localized, NOS Stated as T1, NOS with no other information on extension	T1NOS	T1NOS	Pleural Effusion Extension	Pleural Effusion Extension
305	Localized, NOS	T1NOS	T1NOS	Pleural Effusion Extension	Pleural Effusion Extension
420	Diaphragm (diaphragmatic muscle)	T2	T2	Pleural Effusion Extension	Pleural Effusion Extension
500	Mesothelioma nodule(s) which have broken through the visceral pleural surface to the lung surface Lung parenchyma, or lung involvement, NOS	T2	T2	Pleural Effusion Extension	Pleural Effusion Extension
510	Stated as T2 with no other information on extension	T2	T2	Pleural Effusion Extension	Pleural Effusion Extension
520	Adjacent connective tissue: Pericardium, non-transmural or NOS Endothoracic fascia	T3	T3	Pleural Effusion Extension	Pleural Effusion Extension
610	Chest wall, solitary focus of tumor ONLY Mediastinal tissues, mediastinal fat	T3	T3	Pleural Effusion Extension	Pleural Effusion Extension
620	Stated as T3 with no other information on extension	T3	T3	Pleural Effusion Extension	Pleural Effusion Extension
630	Diffuse or multifocal invasion of soft tissues of chest wall Heart muscle, myocardium Mediastinal organs Rib	T4	T4	Pleural Effusion Extension	Pleural Effusion Extension
650	Extension to internal surface of pericardium	T4	T4	Pleural Effusion Extension	Pleural Effusion Extension
690	Pericardial effusion with positive cytology	T4	T4	Pleural Effusion Extension	Pleural Effusion Extension
780	Contralateral pleura (For contralateral lung, see CS Mets at DX)	T4	T4	Pleural Effusion Extension	Pleural Effusion Extension
800	Further contiguous extension: Brachial plexus Cervical tissues Intra-abdominal organs Peritoneum Spine	T4	T4	Pleural Effusion Extension	Pleural Effusion Extension
850	Stated as T4 with no other information on extension	T4	T4	Pleural Effusion Extension	Pleural Effusion Extension
950	No evidence of primary tumor	T0	T0	Pleural Effusion Extension	Pleural Effusion Extension
999	Unknown; extension not stated Primary tumor cannot be assessed Not documented in patient record	TX	TX	Pleural Effusion Extension	Pleural Effusion Extension

- For CS Extension codes 120-999, the assignment of Summary Stage 1977 and Summary Stage 2000 depends on the value of CS Site-Specific Factor 1, Pleural Effusion, as shown in the Extension Pleural Effusion Table for this schema.