Expression of CD10 predicts tumor progression and unfavorable prognosis in malignant melanoma

Background: CD10 expression in malignant melanoma (MM) has been reported to increase according to tumor progression and metastasis; however, its association with patient outcome has not been clarified. Objective: We examined the immunohistochemical expression of CD10 in MM to determine whether or not it could serve as a marker for tumor progression and prognosis. Methods: A total of 64 formalin-fixed, paraffin-embedded samples of primary MM were immunostained for CD10. Similarly, 40 samples of melanocytic nevus and 20 of metastatic MM were analyzed for comparison. The following clinicopathologic variables were evaluated: age, gender, histologic type, tumor site, Breslow thickness, Clark level, the presence or absence of ulceration and tumor-infiltrating lymphocytes, and survival. Statistical analyses were performed to assess for associations. Several parameters were analyzed for survival using the Kaplan-Meier method and Cox proportional hazards model. Results: Immunohistochemical analysis revealed that 34 of 64 cases (53%) of primary MM expressed CD10, compared with 15 of 20 cases (75%) of metastatic MM and only 4 of 40 cases (10%) of nevus. There was a significant positive relationship between CD10 expression and Breslow thickness, Clark level, and ulceration. Univariate analysis revealed 4 significant factors for shorter survival periods: CD10 expression, high Breslow thickness, high Clark level, and the presence of ulceration (P <.01 each). In multivariate analysis, CD10 expression was revealed to be a statistically significant and independent prognostic factor. Limitations: The major limitation was the small sample size. Conclusion: CD10 expression may serve as a progression marker and can predict unfavorable prognosis in patients with MM.