Lung Cancer TNM Staging (9th Edition)

IASLC / UICC / AJCC TNM 9th Edition (2025)

Looks up the overall stage group from T, N, and M categories using the IASLC 9th edition (effective 2025). Incorporates N2a/N2b and M1c1/M1c2 subdivisions and the rearranged IIA–IIIB groupings.

Also searched as: lung-cancer · iaslc · nsclc · 9th-edition

T category

Primary tumor category (9th ed. T descriptors unchanged from 8th ed. for size/invasion).

N category

9th ed. subdivides N2 into N2a (single station) and N2b (multiple stations).

M category

9th ed. subdivides M1c into M1c1 (single organ system) and M1c2 (multiple organ systems).

Information

Incomplete input

Please provide: T category, N category, M category.

How this tool works

The ninth edition of the TNM classification for lung cancer, developed by the IASLC Staging Project and adopted for use from January 2025, leaves T descriptors essentially unchanged from the eighth edition but subdivides N2 into single-station (N2a) and multi-station (N2b) disease and M1c into single-organ-system (M1c1) versus multi-organ-system (M1c2) metastases. These changes reassign several T/N combinations among stages IIA, IIB, IIIA, and IIIB (notably T1N1 → IIA, T1N2a → IIB, and differential staging of N2a vs N2b with T2/T3). Stage IVA covers M1a and M1b; stage IVB covers any M1c. The system applies to NSCLC and is also recommended for SCLC staging.

References

Implemented from the cited published sources. Educational use only; confirm against current guidelines before clinical use.

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