PASS (Pheochromocytoma Histologic Score)
PASS (Pheochromocytoma of the Adrenal gland Scaled Score, Thompson 2002): 12 histologic features (8 worth 2 points, 4 worth 1) summed 0-20.
Open the calculator → Runs in your browser. Data leaves only if you deliberately send a problem report from the interactive tool.
Example
- Large nests or diffuse growth
- Yes
- Central or confluent tumor necrosis
- Yes
Result: PASS 4 of 20 — potential for aggressive behavior (>= 4).
The tool opens with these values already filled in. Replace them with your own.
What the result means
- Features
- 12 histologic features summed 0-20: 8 are worth 2 points each (nests, necrosis, cellularity, monotony, spindling, mitoses, atypical mitoses, adipose extension) and 4 worth 1 point.
- Cutoff
- PASS >= 4 = potential for biologically aggressive behavior; < 4 = benign. Poor interobserver reproducibility (Wu 2009) - a low score is more reliable; a risk aid, not a definitive malignancy call.
What you enter
- Large nests or diffuse growth (+2)
- Central or confluent tumor necrosis (+2)
- High cellularity (+2)
- Cellular monotony (+2)
- Tumor cell spindling (+2)
- Mitotic figures > 3 per 10 HPF (+2)
- Atypical mitotic figures (+2)
- Extension into adipose tissue (+2)
The other 4 fields
- Vascular invasion (+1)
- Capsular invasion (+1)
- Profound nuclear pleomorphism (+1)
- Nuclear hyperchromasia (+1)
How this is calculated
Thompson LDR. Pheochromocytoma of the Adrenal gland Scaled Score (PASS) to separate benign from malignant neoplasms: a clinicopathologic and immunophenotypic study of 100 cases. Am J Surg Pathol. 2002;26(5):551-566. Read the source ↗
A reference and educational tool. Not medical, legal, or financial advice, and not a substitute for clinician judgment.