Objective: To investigate the significance of the preferentially expressed antigen in melanoma (PRAME) in the differential diagnosis of the conjunctival malignant melanoma and pigmented nevus. Methods: Specimens from 86 patients with conjunctival malignant melanoma (42 males and 44 females, aged 18 to 84 years) and 86 patients with conjunctival pigmented nevus (47 males and 39 females, aged 1 to 82 years) were collected at Zhongshan Ophthalmic Center, Sun Yat-sen University from January 2017 to July 2024. Immunohistology was performed to detect the PRAME expression. The difference of PRAME expression in the two kinds of conjunctival melanocyte hyperplasia lesions and the correlation of PRAME expression with clinical stages of the conjunctival malignant melanoma (T1 to T4) were analyzed. Results: Most patients with malignant melanoma had a positive PRAME expression (89.53%, 77/86), while only 1 patient with pigmented nevus showed a positive PRAME expression (1.16%, 1/86). The positive expression rate of the PRAME in conjunctival malignant melanoma tissues was significantly higher than that in conjunctival pigmented nevi (P<0.05). The PRAME had a sensitivity and specificity of 89.53% and 98.84%, respectively. The expression of the PRAME among patients with conjunctival malignant melanoma in different age groups (>50, 30 to 50, <30) was significantly different (P<0.05). However, the PRAME expression had no difference in different clinical stages of the conjunctival malignant melanoma (P>0.05). Conclusions: The PRAME has significance in discriminating the conjunctival malignant melanoma and pigmented nevus. It is a useful biomarker in the diagnosis of conjunctival malignant melanoma.
目的： 探讨黑色素瘤特异性抗原（PRAME）对结膜恶性黑色素瘤与色素痣的鉴别诊断作用。 方法： 收集2017年1月至2024年7月在中山大学中山眼科中心经手术获得的86例结膜恶性黑色素瘤标本（男性42例，女性44例，年龄18~84岁）和86例结膜色素痣标本（男性47例，女性39例，年龄1~82岁）。采用免疫组织化学检测方法比较PRAME在结膜恶性黑色素瘤和结膜色素痣标本中的表达，分析PRAME表达与结膜恶性黑色素瘤的临床分期（T1至T4期）和患者年龄的关系。采用卡方检验和秩和检验进行统计学分析。 结果： 在86例结膜恶性黑色素瘤标本中，PRAME阳性表达77例，阴性表达9例，阳性率为89.53%；在86例结膜色素痣标本中，仅1例PRAME局灶阳性表达，阴性表达85例，阳性率为1.16%。PRAME在两种病变中的阳性表达差异有统计学意义（P<0.05），PRAME在结膜恶性黑色素瘤与色素痣的鉴别诊断中的敏感度和特异度分别为89.53%及98.84%。不同年龄段（>50、30~50、<30岁）患者结膜恶性黑色素瘤的PRAME表达差异有统计学意义（P<0.05）；不同临床分期结膜恶性黑色素瘤的PRAME表达差异无统计学意义（P>0.05）。 结论： PRAME对结膜恶性黑色素瘤与结膜色素痣具有鉴别诊断作用和价值，是一种有助于明确诊断结膜恶性黑色素瘤的生物标志物。.