Prognostic value of galectin‐3 in primary cutaneous melanoma

Background Galectin‐3, one of the β‐galactoside‐binding lectins, has been suggested as a marker of disease progression in melanoma patients because of its overexpression observed in recent studies. However, prognostic value of galectin‐3 in primary cutaneous melanoma (PCM) has not been clearly defined. Objectives The aim of the study was to analyse whether the intensity of galectin‐3 expression can predict survival in patients with PMC. Methods Galectin‐3 expression was evaluated using immunohistochemistry in 104 PCM samples, including 71 (68.2%) superficial spreading (SSM) and 33 (31.8%) nodular melanomas (NM). Results Significant difference of galectin‐3 expression between SSM and NM was determined (P < 0.001). Increased galectin‐3 expression was positively correlated with tumour thickness (P < 0.001), Clark (P < 0.001) and Breslow (P < 0.001) stage, mitotic rate (P < 0.001), presence of tumour ulceration (P < 0.001), lymphatic invasion (P = 0.018), positive sentinel lymph node (P < 0.022) and distant metastases (P < 0.001). Kaplan–Meier analysis showed an association between increased galectin‐3 expression and reduced recurrence‐free survival (RFS) (P = 0.001) and reduced disease‐specific survival (DSS) (P = 0.015). In Cox proportional hazards regression analysis, significant predictors of reduced RFS were positive sentinel lymph node (P = 0.025) and lymphovascular invasion (P = 0.021), whereas predictors of DSS were tumour thickness (P = 0.012), lymphovascular invasion (P = 0.047), Clark stage (P = 0.029) and location of tumour on upper extremities (P = 0.024). Conclusions Our results support the potential role of galectin‐3 in PCM development, progression and metastasis. Moreover, galectin‐3 could serve as an additional prognostic marker that might help in further stratifying the risk of disease progression and metastasis in patients with PMC.