Prognostic Implications of Tumor Diameter in Association With Gene Expression Profile for Uveal Melanoma

IMPORTANCE: Uveal melanoma (UM) can be divided into prognostically significant subgroups based on a prospectively validated and widely used 15-gene expression profile (GEP) test. Class 1 UMs have a low risk and class 2 UMs have a high risk for metastasis. OBJECTIVE: To determine whether any clinicopathologic factors provide independent prognostic information that may enhance the accuracy of the GEP classification. DESIGN, SETTING, AND PARTICIPANTS: This retrospective observational study performed at 2 ocular oncology referral centers included 339 patients in a primary cohort and 241 patients in a validation cohort. Both cohorts had a diagnosis of UM arising from the ciliary body and/or choroid. All patients underwent tumor biopsy for GEP prognostic testing. Clinicopathologic variables included patient age and sex, tumor thickness, largest basal tumor diameter (LBD), ciliary body involvement, and pathologic cell type. Patients from the primary cohort were enrolled from November 1, 1998, to March 16, 2012; from the validation cohort, from November 4, 1996, to November 7, 2013. Follow-up for the primary cohort was completed on August 18, 2013; for the validation cohort, December 10, 2013. Data were analyzed from November 12, 2013, to November 25, 2015. MAIN OUTCOME AND MEASURES: Progression-free survival (PFS). The secondary outcome was overall survival. RESULTS: The primary cohort included 339 patients (175 women [51.6%]; mean [SD] age, 61.8 [13.6] years). The most significant prognostic factor was GEP classification (exp[b], 10.33; 95% CI, 4.30–24.84; P < .001). The only other variable that provided independent prognostic information was LBD (exp[b], 1.13; 95% CI, 1.02–1.26; P = .02). Among class 2 UMs, LBD showed a modest but significant association with PFS (exp[b], 1.13; 95% CI, 1.04–1.24; P = .005). The 5-year actuarial metastasis-free survival estimates (SE) were 97% (3%) for class 1 UMs with LBD of less than 12 mm, 90% (4%) for class 1 UMs with LBD of at least 12 mm, 90% (9%) for class 2 UMs with LBD of less than 12 mm, and 30% (7%) for class 2 UMs with LBDs of at least 12 mm. The independent prognostic value of LBD and the 12-mm LBD cutoff were corroborated in the independent validation 241-patient cohort. CONCLUSIONS AND RELEVANCE: Class 2 UMs had better prognosis when the LBD was less than 12 mm at the time of treatment. These findings could have important implications for patient counseling, primary tumor treatment, clinical trial enrollment, metastatic surveillance, and adjuvant therapy

Transcriptomic versus chromosomal prognostic markers and clinical outcome in uveal melanoma

To compare a gene expression-based classifier versus the standard genetic prognostic marker, monosomy 3, for predicting metastasis in uveal melanoma.Gene expression profiling, fluorescence in situ hybridization (FISH), and array comparative genomic hybridization (aCGH) were done on 67 primary uveal melanomas. Clinical and pathologic prognostic factors were also assessed. Variables were analyzed by Cox proportional hazards, Kaplan-Meier analysis, sensitivity, specificity, positive and negative predictive value, and positive and negative likelihood ratios.The gene expression-based molecular classifier assigned 27 tumors to class 1 (low risk) and 25 tumors to class 2 (high risk). By Cox univariate proportional hazards, class 2 signature (P = 0.0001), advanced patient age (P = 0.01), and scleral invasion (P = 0.007) were the only variables significantly associated with metastasis. Only the class 2 signature was needed to optimize predictive accuracy in a Cox multivariate model. A less significant association with metastasis was observed for monosomy 3 detected by aCGH (P = 0.076) and FISH (P = 0.127). The sensitivity and specificity for the molecular classifier (84.6% and 92.9%, respectively) were superior to monosomy 3 detected by aCGH (58.3% and 85.7%, respectively) and FISH (50.0% and 72.7%, respectively). Positive and negative predictive values (91.7% and 86.7%, respectively) and positive and negative likelihood ratios (11.9 and 0.2, respectively) for the molecular classifier were also superior to those for monosomy 3.Molecular classification based on gene expression profiling of the primary tumor was superior to monosomy 3 and clinicopathologic prognostic factors for predicting metastasis in uveal melanoma