Nucleolar size in choroidal and ciliary body melanomas and corresponding hepatic metastases

This study aimed to investigate the relationship between hepatic metastasis and the mean diameter of the 10 largest nucleoli (MLN) in uveal melanoma.

A cross-sectional histopathological analysis of 37 metastases (13 surgical or needle biopsies, 24 autopsies) and corresponding primary choroidal and ciliary body melanomas was conducted, using statistical tests appropriate for paired data. The largest nucleoli were measured from digital photographs of silver-stained sections along a 5-mm-wide linear field. Confounders considered were presence of epithelioid cells and microvascular density (MVD), counted as the number of discrete elements labelled by monoclonal antibody QBEND/10 to the CD34 epitope.

Hepatic metastases had more frequent epithelioid cells (p = 0.0047) and a higher MVD (median difference, 7.5 counts/0.313 mm(2) more; p = 0.044) than their corresponding primary tumours. Hepatic metastases, especially in autopsy specimens rather than surgical biopsies, tended to have a smaller MLN (median 3.6 mum) than the corresponding primary tumour (median difference, 0.55 mum; p = 0.066). The MLN in hepatic metastases was not associated with presence of epithelioid cells and MVD. Overall survival after diagnosis of metastasis was comparable whether hepatic metastases had a large or small MLN (p = 0.95), whereas a high MVD tended to be associated with shorter survival (p = 0.096) among the 13 patients with known survival.

The results suggest that MLN is not a useful marker for assessing prognosis after diagnosis of hepatic metastasis from uveal melanoma.