RESUMO
@#Objective: To investigate the expression of phosphorylated retinoblastoma (p-Rb) in advanced melanoma tissues and to analyze its correlation with clinical pathological characteristics and prognosis. Methods: The clinical data and paraffin-embedded tissue sections of 66 patients with advanced melanoma, who were diagnosed and treated in the Department of Renal Cancer and Melanoma of Peking University Cancer Hospital from 2011 to 2014, were collected. Expression of p-Rb in primary tumor tissues was detected by immunohistochemistry. Correlation analysis was performed on the relationship between the expression level of p-Rb in tumor tissues and clinical data such as clinicopathological features and overall survival. Results: The positive expression rate of p-Rb in advanced melanoma tissues was 57.6% (38/66). The positive rates of p-Rb in non-acral cutaneous type, acral type and mucosal type were 73.7% (14/ 19), 63.0% (17/27) and 35.0% (7/20), respectively, and the difference was statistically significant (P=0.039). The positive rate of p-Rb in different gene mutation subgroups was also different, with 83.3% (5/6) in the BRAF mutation group, 100.0% (2/2) in the c-KIT mutation group, and 100.0% in the N-RAS mutation group (9/9), 50.0% (1/2) in the PDGFRA mutation group, and 50.0% (1/2) in group with 2-gene mutation, and 44.4% (20/45) in the wild type gene group, and the difference was statistically significant (P=0.004). There was no correlation between p-Rb expression levels and age, gender, stage, ulcer, and serum LDH levels. The median overall survival (OS) of patients with positive p-Rb expression was slightly shorter than that of the patients with negative expression (30.0 vs 39.2 months), but the difference was not statistically significant (P=0.555). Conclusion: More than half of the advanced melanoma tissues have positive expression of p-Rb, and the positive rate of p-Rb in non-acral cutaneous type is higher than that of acral and mucosal types.And the positive rate of p-Rb in melanoma tissues of patients carrying c-KIT and N-RAS mutations is higher.