Clinical calculator summary
Original 1984 Nine-Criterion Weiss Score
Clinical calculator summary
Original 1984 Nine-Criterion Weiss Score
An additive histopathology score using nine microscopic criteria in conventional adrenocortical tumors.
Evidence-based context for fast calculator use
- Purpose:
- Reproduce the original criterion count and operational threshold without implying a definitive diagnosis or treatment decision.
- Population:
- Resected conventional adult adrenocortical tumors assessed by an expert pathologist.
- Factors:
- Nuclear grade, Mitotic count and atypical mitoses, Clear-cell and diffuse architecture percentages, Necrosis and venous, sinusoidal, and capsular invasion
- Reference:
- Weiss LM. Am J Surg Pathol. 1984;8(3):163-169.
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Weiss Score (Adrenal)
% of tumor
% of tumor
Clinical Context & Background
This calculator reproduces the original 1984 nine-criterion Weiss system. It assigns one point for each source-defined histologic criterion and reports whether the operational score threshold of three is met.
The result requires expert adrenal-pathology interpretation. Scores 2 and 3 are borderline between benign and malignant behavior, and a score below three is not definitive evidence of benignity. The system is intended for resected conventional adult adrenocortical tumors and is not appropriate for biopsy-only assessment, pediatric tumors, or oncocytic variants. It is not a staging, prognostic, surveillance, or treatment-selection tool.
Formula Logic
Original 1984 nine-criterion Weiss score = one point each for nuclear grade III/IV, mitoses >5 per 50 HPF, atypical mitoses, clear cells <=25%, diffuse architecture >1/3, microscopic necrosis, venous invasion, sinusoidal invasion, and capsular invasion.Reference Data
| Total score | Operational threshold | Important caution |
|---|---|---|
| 0-2 | Malignancy threshold not met | A score below 3 is not definitive evidence of benign behavior; score 2 is borderline |
| >=3 | Malignancy threshold met | Score 3 is borderline and requires expert pathology review |
Clinical Workflow
Use, Interpret, And Continue The Patient Pathway
Expand for workflow guidance, limitations, examples, and related next steps.
Clinical Workflow
Use, Interpret, And Continue The Patient Pathway
Expand for workflow guidance, limitations, examples, and related next steps.
When To Use
- Use after resection of a conventional adult adrenocortical tumor when all nine histologic criteria can be assessed.
- Enter the exact mitotic count per 50 HPF and unrounded percentages for clear cells and diffuse architecture.
How To Interpret
- Scores 0-2 do not meet the operational threshold; scores >=3 meet it.
- Scores 2 and 3 are borderline and warrant expert adrenal-pathology review. A score below 3 is not definitive proof of benign behavior.
What To Do Next
- Integrate the result with expert pathology review, Ki-67, resection status, stage, imaging, endocrine findings, and multidisciplinary assessment.
- Use an appropriate variant-specific system for oncocytic tumors rather than the conventional Weiss score.
Limitations
- Not for biopsy-only assessment, pediatric tumors, or oncocytic adrenocortical tumors.
- Not a staging, prognostic, surveillance, or treatment-selection tool.
- Individual histologic criteria require expert interpretation and should not be inferred from incomplete specimens.
Validated Population
Resected conventional adult adrenocortical tumors evaluated histologically.
Exact clear-cell boundary
Clear cells comprising exactly 25% of the tumor meet the original criterion and add one point.
Calculation verification history
Verified
Calculation verification history
Verified: Production browser revalidation
- Three source-backed cases passed through all nine visible production criteria at scores 0, borderline threshold 3, and maximum 9.
- Raw equality behavior remained correct at mitoses 5 versus 6, clear cells 25%, and diffuse architecture below versus above one third.
- No unexpected N/A, stale control, literal undefined/null value, or browser-console error was observed.
Case-level evidence is retained in validation/browser-revalidation/weiss-acc-2026-08-03.json.
: Production browser validation
- Ten source-backed cases were exercised on the public production route through visible browser controls; 10/10 case records passed their expected-versus-observed assertions across 11 visible submissions.
- Overall browser status: failed-console. medium: Production emitted minified React error #418 during route loads/reloads used by this run.
- Case-level inputs, expected and observed results, reset/repeat behavior, failure reproductions, and console evidence are retained in the production-browser evidence record.
Case-level production evidence is retained in validation/browser-production/weiss-acc.json.
: Browser input adapter corrected and reverified
- Accepted finite number values already normalized by the shared calculator form while retaining strict malformed-input rejection.
- No equation, cutoff, unit, classification, or applicability rule changed; calculator-specific verification and the calculator-wide browser-input audit passed.
: Full validation test
- 768/768 source-rule, threshold, invalid-input, trace, wording, scope, UI/integration, and immutability checks passed, including all 512 binary criterion combinations.
- No registered master panel calculates the Weiss score; no panel receives inherited verification.
: Calculation and input-contract correction
- Replaced nine favorable pre-scored defaults and arbitrary Object.values summation with exact raw grade, mitotic-count, percentage, and invasion categories plus strict validation.
- Preserved clear cells at 25% as positive and diffuse architecture only above one third as positive; removed definitive benign wording and added explicit score 2-3 borderline and variant-scope cautions.
Verification confirms the calculator implementation against the cited model; it is not independent clinical validation, regulatory approval, or medical advice.
Related Tools
Frequently Asked Questions
Do clear cells exactly at 25% add a point?
Yes. The original publication describes clear cells comprising 25% or less of the tumor.
Is a Weiss score of 2 definitively benign?
No. A score of 2 is borderline and requires expert pathology review; a score below 3 is not definitive evidence of benign behavior.
Can this calculator be used for oncocytic adrenocortical tumors?
No. Oncocytic tumors require an adapted system such as Lin-Weiss-Bisceglia.
Evidence-based oncology decision support. Verify with clinical guidelines.