The Briganti nomogram is a risk-prediction tool used in prostate cancer care to estimate the probability of lymph node invasion (LNI) before surgery. This page gives you a practical, easy-to-use calculator with clear interpretation guidance so you can understand what each input means and how clinicians often use threshold values in decision-making.
Briganti-Style LNI Risk Calculator
Enter preoperative information to estimate the probability of lymph node involvement.
What is the Briganti nomogram?
The Briganti nomogram is a validated predictive model designed to estimate the chance that prostate cancer has spread to pelvic lymph nodes. It helps support the preoperative conversation about whether an extended pelvic lymph node dissection (ePLND) may be beneficial at the time of radical prostatectomy.
Instead of relying on one factor alone, the nomogram combines several clinical features. This gives a more individualized estimate than using PSA level or Gleason score in isolation.
How this calculator works
This page uses a logistic risk model based on the same core predictors used in Briganti-style assessments:
- PSA level
- Clinical stage (cT1, cT2, cT3)
- Biopsy grade group (ISUP 1 to 5)
- Percentage of positive biopsy cores
The calculator first computes the positive-core percentage from your entries, then applies weighted coefficients to produce a probability estimate from 0% to 100%.
Inputs explained
- PSA: Prostate-specific antigen value measured before treatment.
- Clinical stage: Tumor extent based on exam and imaging.
- Grade group: Pathology-based aggressiveness category.
- Positive cores: Number of sampled cores containing cancer.
How to interpret the estimated risk
Many centers use a threshold strategy when discussing ePLND. A commonly referenced approach is:
- < 5%: lower estimated LNI risk; some teams may consider avoiding ePLND in selected patients.
- 5% to < 7%: borderline zone; individual factors, MRI findings, and surgeon judgment matter.
- ≥ 7%: higher estimated risk; ePLND is more often considered.
These cutoffs are not absolute rules. Institutional protocols and evolving guidelines can differ.
Worked example
Suppose a patient has PSA 9.2 ng/mL, cT2 disease, Grade Group 3, and 4 positive cores out of 12. The positive-core rate is 33.3%. Entering those values yields a moderate risk estimate. In practice, the care team would combine this result with MRI findings, patient goals, surgical plan, and overall health profile before making a final recommendation.
Limitations and good clinical practice
Why this should not be used in isolation
No nomogram can capture every factor that influences outcomes. Real-world decisions may also depend on:
- MRI features and lesion characteristics
- Genomic classifiers and pathology nuances
- Comorbidities and operative risk
- Patient preference and quality-of-life priorities
For these reasons, this calculator should be treated as a conversation aid, not a standalone diagnostic tool.
FAQ
Is this the same as a hospital-grade decision system?
No. It is an educational implementation designed to mirror Briganti nomogram logic and variables.
Can this diagnose lymph node metastasis?
No. It estimates probability only. Diagnosis requires clinical evaluation, imaging, and/or pathology.
What if my values are near a cutoff?
Borderline estimates should always be interpreted by your urologic oncology team in full context.