From: Ectopic adrenocortical adenoma in the renal hilum: a case report and literature review
Original Weiss criteria | Modified Weiss criteria |
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Nuclear grade III or IV based on Fuhrman criteria | Mitotic rate >5 per 50 high-power fields |
>5 mitotic figures/50 HPF (40× objective), counting 10 random fields in area of greatest number of mitotic figures on 5 slides with greatest number of mitoses | Cytoplasm (clear cells comprising 25 % or less of the tumor) |
Presence of atypical mitotic figures (abnormal distribution of chromosomes or excessive number of mitotic spindles) | Abnormal mitoses |
Clear or vacuolated cells comprising 25 % or less of tumor | Necrosis |
Diffuse architecture (more than 1/3 of tumor forms patternless sheets of cells; trabecular, cord, columnar, alveolar or nesting pattern is not considered to be diffuse) | Capsular invasion |
Microscopic necrosis | |
Venous invasion (veins must have smooth muscle in wall; tumor cell clusters or sheets forming polypoid projections into vessel lumen or polypoid tumor thrombi covered by endothelial layer) | |
Sinusoidal invasion (sinusoid is endothelial lined vessel in adrenal gland with little supportive tissue; consider only sinusoids within tumor) | |
Capsular invasion (nests or cords of tumor extending into or through capsule with a stromal reaction); either incomplete or complete | |
Calculate: score of 3 or more suggests malignancy | Calculate: 2× mitotic rate criterion + 2× clear cytoplasm criterion + abnormal mitoses + necrosis + capsular invasion (score of 3 or more suggests malignancy) |
Each criterion is scored 0 when absent and 1 when present in the tumor | Each criterion is scored 0 when absent and 1 when present in the tumor |