# TNM staging for prostate cancer, and what changed in the 9th edition

Source: https://onco.cc/terms/tnm-prostate-cancer/  
OnCo record `tnm-prostate-cancer` (Term). Data CC BY-NC 4.0, attribute "Data from OnCo (onco.cc)"; commercial use needs a licence.

## TL;DR

The anatomical stage of prostate cancer: how far the tumour has grown (T), whether it is in the pelvic lymph nodes (N) and whether it has spread further (M). UK reports use the 8th edition; the 9th, recommended from January 2026, leaves the prostate categories alone but asks reports to say which scan the stage came from.

## Summary

T1 is a tumour that cannot be felt or seen on imaging, with T1c the commonest entry point of all, a cancer found by needle biopsy after a raised PSA. T2 is a tumour confined within the prostate, T3a is extension through the capsule including microscopic bladder neck involvement, T3b is invasion of a seminal vesicle, and T4 is a tumour fixed to or invading the rectum, the external sphincter, the levator muscles or the pelvic wall. N1 is any regional pelvic node. M1a is a non-regional node, M1b bone and M1c anywhere else. There is no pT1 category, because the pathologist is given too little tissue to exclude a higher one, and the eighth edition removed the substaging of pT2, so a prostatectomy report says pT2 without a letter after it.

The Royal College of Pathologists dataset in force in the UK (G084, version 4, October 2024) names the UICC 8th edition and reprints it as its appendix. The 9th edition was published on 3 July 2025 and UICC recommends it take effect from 1 January 2026; for prostate the T, N and M categories are unchanged. Two things did change. The clinical stage grouping was clarified, with stage I as cT1 or cT2a, stage II as cT2 (or pT2) and cT2b or cT2c, stage III as cT3 or cT4, and stage IV as any node or any metastasis, and with a note that there is no pathological stage I. And the edition introduced imaging suffixes: a T category read from MRI is written cT2b(mr), and a node found on PSMA PET is N1(PET), stage IV(PET). The reason is that prostate is, in the TNM committee's own words, 'probably the malignancy most affected by stage migration'. The eighth edition set the clinical T category from the digital rectal examination alone; MRI and PSMA PET find disease a finger cannot, so a man staged IV on a PSMA PET in 2026 may have far less disease than a man staged IV before those scans existed, and his prognosis is not the same. NICE NG131 names no TNM edition; its Cambridge Prognostic Group table uses bare T1 to T4, which are identical in both editions, so the guideline is not stranded by the change.

## Fields

- Kind: Term
- Last checked: 2026-09-25
- Also known as: TNM prostate; prostate TNM; T1c; T2b; T3a; T3b; pT2; pT3a; pT3b; cT2b(mr); N1(PET); TNM 9; TNM 8; UICC TNM prostate

## Sources

- Wikipedia: https://en.wikipedia.org/wiki/Prostate_cancer_staging
- Brierley et al., International Journal of Cancer 2026: the 9th edition of the UICC TNM classification of malignant tumours, updates and rationale for change (prostate at section 10.1): https://doi.org/10.1002/ijc.70561
- UICC: the 9th edition of the TNM classification of malignant tumours, published 3 July 2025 and recommended to take effect from 1 January 2026: https://www.uicc.org/news-and-updates/25-7-announcements/9th-edition-uicc-tnm-classification-malignant-tumours-now-available
- Royal College of Pathologists G084: dataset for histopathology reports for prostatic carcinoma, version 4, October 2024: https://www.rcpath.org/static/8cc88604-2c8d-4df4-a99542df41c102af/G084-dataset-for-histopathology-reports-for-prostatic-carcinoma.pdf
- NICE NG131: prostate cancer, diagnosis and management (recommendations, including the Cambridge Prognostic Group table at 1.2.15): https://www.nice.org.uk/guidance/ng131/chapter/Recommendations

## Connected records

- terms: [Cambridge Prognostic Group (CPG 1 to 5)](https://onco.cc/terms/cambridge-prognostic-group/), [Castration-resistant prostate cancer (CRPC)](https://onco.cc/terms/castration-resistance/), [Disease-specific staging and risk systems (FIGO, Ann Arbor, IPI, R-ISS, ELN, IMDC)](https://onco.cc/terms/staging-systems/), [Extraprostatic extension and seminal vesicle invasion](https://onco.cc/terms/extraprostatic-extension/), [Gleason score / Grade Group](https://onco.cc/terms/gleason-grade-group/), [Grade versus stage](https://onco.cc/terms/grade-vs-stage/), [mCRPC and mHSPC (castration-resistant vs hormone-sensitive prostate cancer)](https://onco.cc/terms/mcrpc-mhspc/), [Metastasis-free survival (MFS)](https://onco.cc/terms/metastasis-free-survival/), [Radical prostatectomy](https://onco.cc/terms/prostatectomy/), [Stage](https://onco.cc/terms/cancer-stage/), [TNM staging](https://onco.cc/terms/tnm-staging/)
- cancers: [Biochemical recurrence of prostate cancer](https://onco.cc/cancers/prostate-bcr/), [Ductal adenocarcinoma of the prostate](https://onco.cc/cancers/prostate-ductal-adenocarcinoma/), [Localised prostate cancer, high and very high risk](https://onco.cc/cancers/prostate-high-risk/), [Localised prostate cancer, intermediate risk](https://onco.cc/cancers/prostate-intermediate-risk/), [Localised prostate cancer, very low and low risk](https://onco.cc/cancers/prostate-low-risk/), [Metastatic castration-resistant prostate cancer](https://onco.cc/cancers/prostate-mcrpc/), [Metastatic hormone-sensitive prostate cancer](https://onco.cc/cancers/prostate-mhspc/), [Neuroendocrine and small-cell prostate cancer](https://onco.cc/cancers/prostate-nepc/), [Non-metastatic castration-resistant prostate cancer](https://onco.cc/cancers/prostate-nmcrpc/), [Prostate cancer](https://onco.cc/cancers/prostate/)
- fronts: [Diagnostics & Biomarkers](https://onco.cc/fronts/diagnostics/)
- technologies: [Multiparametric prostate MRI (PI-RADS)](https://onco.cc/technologies/mp-mri/), [PSMA PET](https://onco.cc/technologies/psma-pet/)

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