Table 4

Schoolmeester criteria for prognosis in PEComa (from Schoolmeester et al20)

CriteriaCases with known metastasis meeting criteria (%)Cases without known metastasis meeting criteria (%)
Benign or uncertain malignant potentialTumours with less than four features: gross size ≥5 cm, high-grade nuclear features, necrosis, vascular invasion, or a mitotic rate greater than or one per 50 HPF0 of 9 (0)7 of 7 (100)
MalignantTumours with four or more features9 of 9 (100)0 of 7 (0)
  • HPF, high power field; PEComas, perivascular epithelioid tumours.