Prognostic blood
biomarkers for patients with
uveal melanoma have not been identified.
Tumor monosomy-3 is strongly associated with the development of metastatic disease.
Tumor expression of
human leukocyte antigen class I molecules and
insulin-like growth factor (IGF)-1 receptor has also been associated with the development of metastatic disease. The relationship of blood levels of the
human leukocyte antigen-class-I-associated β-2 microglobulin (β2M),
IGF-1, and its
binding protein,
IGFBP-3, with
tumor monosomy-3 was evaluated. Blood was drawn from patients with a clinical diagnosis of primary
uveal melanoma without metastatic disease before fine-needle aspiration biopsy at the time of
brachytherapy or enucleation.
Tumor chromosome 3 status was determined by fluorescence in-situ hybridization. β2M,
IGF-1, and
IGFBP-3 levels were determined using
enzyme-linked
immunosorbent assays. A total of 76 patients were studied; 47 (62%) underwent
brachytherapy and 29 (38%) underwent enucleation. Thirty-three (43%) of the
tumors manifested monosomy-3. Most
tumors were large, located in the choroid, mixed cell type, and nuclear grade 2. Most
tumors did not manifest extraocular extension. Blood levels of
IGF-1 and
IGFBP-3 were not associated with
tumor monosomy-3. In contrast, increases in blood β2M (P≤0.02) were associated with
tumor monosomy-3. The independent association of increased blood level of β2M and
tumor monosomy-3 status was confirmed in multivariable analysis. In conclusion, measurement of blood levels of β2M in patients with primary
uveal melanoma may have prognostic value and may help guide surveillance and adjuvant
therapy recommendations.