How are Favorable and Unfavorable Intermediate risk distinguished?

Intermediate disease features are cT2b–cT2c, Grade Group 2 or 3, or PSA 10–20 ng/mL. Unfavorable Intermediate is assigned if Grade Group 3 is present, if 2 or more intermediate risk factors are present, or if 50% or more of biopsy cores are positive. Favorable Intermediate requires exactly 1 intermediate factor, Grade Group 1 or 2, and fewer than 50% positive biopsy cores.

Why does missing core data produce an incomplete intermediate evaluation?

Because a patient with 1 intermediate factor and Grade Group 1–2 could harbor 50% or more positive biopsy cores, which reclassifies them as Unfavorable Intermediate. Biopsy core counts are necessary to confirm Favorable Intermediate status.

What are the verified NCCN Very Low risk criteria?

Very Low risk requires all of: cT1c stage, Grade Group 1, PSA < 10 ng/mL, fewer than 3 positive biopsy cores, ≤ 50% cancer involvement in any individual core, and PSA density < 0.15 ng/mL/g.

Does this tool transmit or store protected health information?

No. All evaluations are performed strictly inside your browser. No form entries, calculations, or identifiers are logged or sent to any server.

NCCN Prostate Cancer Risk Stratification Calculator

Enter PSA, Gleason Grade Group, biopsy core details, and clinical T stage to evaluate NCCN localized prostate cancer risk stratification.

Patient Clinical & Pathology Parameters

Provide baseline staging, serology, and biopsy metrics. Educational decision-support tool.

PSA Level (ng/mL) *

Clinical T Stage *

Gleason Grade Group *

Primary Gleason Pattern 5

Systematic Biopsy Core Quantification

Total Cores Examined

Positive Cores

Cores with GG 4 or 5

Very Low Risk Criteria Elements

Max % Cancer in Any Single Core

PSA Density (ng/mL/g)

Unit Relationships & Metric Definitions

Percent Positive Cores: Calculated as (Positive Cores / Total Cores) × 100%. A value ≥ 50% constitutes an unfavorable intermediate-risk feature under NCCN guidelines.

Max Core Cancer Involvement: The highest fraction of malignant involvement in any individual core biopsy. ≤ 50% required for Very Low qualification.

PSA Density (PSAD): Calculated as Serum PSA (ng/mL) divided by Prostate Volume (cc or g) determined by transrectal ultrasound or MRI. PSAD < 0.15 ng/mL/g is required for Very Low risk.

Enter patient parameters and click "Evaluate NCCN Risk Tier".

NCCN Localized Risk Group Reference

Version 2.2024 Criteria

Risk Group	T Stage	Grade Group	PSA (ng/mL)	Additional Criteria
Very Low	cT1c	GG 1	< 10	<3 pos cores, ≤50% cancer/core, PSAD <0.15
Low	cT1–cT2a	GG 1	< 10	Does not meet all Very Low criteria
Fav. Intermediate	cT2b–cT2c *	GG 1–2 *	10–20 *	Exactly 1 IR factor, GG 1–2, and <50% positive cores
Unfav. Intermediate	cT2b–cT2c *	GG 2–3 *	10–20 *	GG 3 OR ≥2 IR factors OR ≥50% positive cores
High	cT3a *	GG 4–5 *	> 20 *	Exactly 1 high-risk factor; no very-high features
Very High	cT3b–cT4	Primary 5	Any	≥2 high factors, or >4 cores with GG 4/5

* Denotes an independent risk factor within that group. Note: MRI targeted cores require pathologist clinical synthesis.

Guideline Scope & Disclaimers

This calculator is strictly an educational screening aid based on published NCCN and AUA/ASTRO localized prostate cancer risk definitions. It does not replace individualized clinical, histopathologic, and multi-parametric MRI assessment by a multidisciplinary oncology care team.

The tool does not estimate life expectancy, evaluate nodal or metastatic staging (cN/cM), or mandate therapeutic interventions.

References: NCCN Prostate Cancer guideline and AUA/ASTRO localized prostate cancer guideline. Verify the current guideline version with the treating team.

Summary

Enter PSA, Gleason Grade Group, biopsy core details, and clinical T stage to evaluate NCCN localized prostate cancer risk stratification.

How it works

Enter the pre-treatment serum PSA level (ng/mL).
Select the biopsy Gleason Grade Group (GG 1 to 5) and indicate if primary Gleason pattern 5 is present.
Enter core counts: total cores examined, total positive cores, and number of GG 4 or 5 cores.
Select the clinical T stage (cT1a through cT4) determined by clinical examination and diagnostic imaging.
For suspected very low risk cases, enter maximum cancer percentage in any core and PSA density.
Click Evaluate to compute the risk tier, review triggered criteria, and check guideline parameters.

Use cases

Educational review of NCCN localized prostate cancer risk groups.
Distinguishing favorable from unfavorable intermediate-risk prostate disease using biopsy core fraction.
Checking clinical criteria for active surveillance candidacy in low and very low risk categories.
Identifying very high-risk criteria such as primary pattern 5, high-grade core burden, or cT3b-cT4 disease.

Frequently Asked Questions

Last updated: 2026-09-20 · Reviewed by Nham Vu