Morphometric analysis of AgNORs in uveal malignant melanoma

OBJECTIVE: To define the value of silver-stained nucleolar organizer region s (AgNOR) in the evaluation of uveal malignant melanomas (MM). STUDY DESIGN: Morphometric analysis of AgNOR was performed on 30 uveal MM o f spindle A, B, epitheIioid and mixed cell types. Findings were compared wi th cytotype, largest tumor dimension (LTD) and clinical outcome. RESULTS: AgNOR mean perimeter (MP) was 3.76 mu m (SD 1.21, range 1.79-8.51 mu m) in A, 5.05 mu m (SD 1.96, range 1.79-16.41 mu m) in B and 6.15 mu m ( SD 3.86, range 1.79-33.80 mu m) in epithelioid MM; mean area (MA) was 0.86 mu m(2) (SD 0.60, range 0.20-2.78 mu m(2)) in A, 1.58 mu m(2) (SD 1.11, ran ge 0.20-9.63 mu m(2)) in B and 2.34 mu m(2) (SD 2.10, range 0.20-15.27 mu m (2)) in epithelioid MM; the aspect ratio (AX) was 3.10 (SD 0.19, range 2.90 -3.35) in A, 5.80 (SD 2.07, range 3.77-9.32) in B and 12.22 (SD 2.84, range 8.11-25.81) in epithelioid MM. From comparing MA and RA with follow-up, it seemed that MM with a good prognosis (spindle A and a subgroup of B tumors , B1) exhibited the lowest MA and AX values, while MM with poorer clinical behavior (epithelioid and a second subgroup of spindle B MM, B2) showed the highest. No correlation was found between AgNORs and LTD. CONCLuSION: AgNORs may contribute to the prognostic evaluation of uveal MM.