Pearl R A, Pacifico M D, Richman P I, Wilson G D, Grover R
RAFT Institute of Plastic Surgery, Mount Vernon Hospital, Northwood, Middlesex HA6 2RN, UK.
J Plast Reconstr Aesthet Surg. 2008;61(3):265-71. doi: 10.1016/j.bjps.2007.04.010. Epub 2007 Jun 13.
The usual indication for sentinel lymph node biopsy (SLNB) in melanoma is a primary tumour >1mm thickness but under these criteria less than 20% of SLNBs are positive. Of those patients with a negative sentinel node (SN) over 10% will have disease recurrence within 3 years. A more accurate delineation of candidate patients for SLNB and risk profile for negative SN patients is therefore desirable. Melanoma cell adhesion molecule (MCAM) is a predominant cell adhesion molecule of melanomas and its expression has been implicated in tumour progression and metastasis.
To compare MCAM expression in primary and metastatic melanoma and to investigate if MCAM expression in patients meeting the criteria for SLNB correlated with patient outcome.
Tissue arrays of primary (n=78) and metastatic (n=92) melanomas were constructed from archived paraffin embedded tissue and MCAM expression detected by immunohistochemistry. Staining positivity and intensity were assessed by visual scoring and correlated with clinical outcome.
In patients meeting the current criteria for SLNB, Cox multivariate analysis showed both MCAM expression positivity and intensity were independently predictive of survival (P=0.007) and development of lymph node disease (P=0.01) in primary melanoma over and above established markers of prognosis, such as Breslow thickness. MCAM-negative patients had a 5-year survival of 92% compared with 40% for MCAM positive.
Measurement of MCAM expression represents a potential method to stratify SLNB patients on the basis of risk. This would have considerable benefits in terms of both cost and patient morbidity.
黑色素瘤前哨淋巴结活检（SLNB）的常见指征是原发性肿瘤厚度>1mm，但按照这些标准，前哨淋巴结活检阳性率不到20%。在前哨淋巴结（SN）阴性的患者中，超过10%的患者会在3年内出现疾病复发。因此，需要更准确地界定适合前哨淋巴结活检的候选患者以及SN阴性患者的风险特征。黑色素瘤细胞粘附分子（MCAM）是黑色素瘤的主要细胞粘附分子，其表达与肿瘤进展和转移有关。
比较原发性和转移性黑色素瘤中MCAM的表达，并研究符合前哨淋巴结活检标准的患者中MCAM的表达是否与患者预后相关。
从存档的石蜡包埋组织构建原发性（n=78）和转移性（n=92）黑色素瘤的组织芯片，通过免疫组织化学检测MCAM表达。通过视觉评分评估染色阳性率和强度，并与临床结果相关联。
在符合当前前哨淋巴结活检标准的患者中，Cox多变量分析显示，MCAM表达的阳性率和强度在原发性黑色素瘤中独立预测生存率（P=0.007）和淋巴结疾病的发生（P=0.01），超过了既定的预后标志物，如Breslow厚度。MCAM阴性患者的5年生存率为92%，而MCAM阳性患者为40%。
检测MCAM表达是一种根据风险对前哨淋巴结活检患者进行分层的潜在方法。这在成本和患者发病率方面都将带来相当大的益处。
