Abstract
Purpose: :
To report the expression of growth hormone receptors (GHR) in uveal melanoma specimens.
Methods: :
Retrospective review of paraffin embedded specimens of patients with uveal melanoma treated by enucleation at 2 institutions between 2002 and 2007. Specimens were stained initially with H&E to confirm the histopathologic diagnosis, cell type, and features such as vascular patterns, retinal and scleral invasion, and extra-ocular extension. Additional information regarding patient age, duration of follow-up, and detection of metastasis were computed. Non-stained sections were tested with immunohistochemical stain MAb 263, (Santa Cruz Biotechnology, Santa Cruz, CA, USA,) to determine the presence of GHR in tumor cells. All microslides (H&E and immuno) were reviewed by 2 independent blinded investigators and graded by each as positive or negative for MAb 263. Discrepant results were discussed and outside review was used to resolve discordant cases.
Results: :
Forty-three paraffin embedded specimens were studied. Tumors were classified according to cell type into spindle B (n=15), mixed (n=15), epithelioid (n=12) and necrotic (n=1) cell types. The mean follow-up was 37.5 months. Through available follow-up, 72.1% of the patients were alive. Metastasis was detected in 18 patients (41.9%). Scleral and retinal invasion were observed in 44.2% and 51.2% of cases, respectively. Extraocular extension was identified in 18.6%. Thirty-eight of the 43 specimens (88.3%) exhibited positive immunoreactivity to MAb 263; among these, 19 were categorized as weakly positive, and the other 19 were categorized as strongly positive. Four cases were considered negative and one was excluded because was associated with a trend (P = 0.057) suggesting that tumors with positive immunoexpression might be associated with poorer prognosis.
Conclusions: :
Growth hormone receptors were expressed by the majority of uveal melanoma specimens evaluated in this study MAb 236 posivitity may be prognostic of poor survival prognosis in uveal melanoma patients.
Keywords: melanoma • growth factors/growth factor receptors • immunohistochemistry