Tenascin-C in primary malignant melanoma of the skin

AIMS: To investigate the expression and the prognostic role of glycoprotein Tenascin-C (Tn-C) in primary melanoma of the skin. METHODS AND RESULTS: The immunohistochemical expression of Tn-C was studied in 98 primary melanomas and related to inflammation, invasion, and patient outcome. Patients were followed up for disease recurrence for 0.04-7.4 years (median 3.9) and for survival for 0.5 to 12.1 years (median 9.3). The expression of Tn-C was evaluated for each tumour invasion border; the stromal and intracytoplasmic Tn-C of the melanoma islets were also recorded. Tn-C is widely expressed in primary melanoma samples, the staining pattern varying from focal to diffuse in different parts of the tumour. No correlation existed between intensity of Tn-C staining and inflammation. No stromal Tn-C was detected at the upper dermal lateral border in 12 patients, nor at the deep, dermal or subcutaneous border in 14 patients. These patients showed better disease-free survival (DFS) than did those cases with focal or diffuse staining (P = 0.06, P = 0.05). Also, absence of intracytoplasmic Tn-C was a beneficial prognostic factor for DFS (P = 0.04). In multivariate analysis, tumour ulceration and intracytoplasmic Tn-C expression of melanoma cells were independent adverse prognostic factors for DFS. CONCLUSIONS: In primary melanoma of the skin, absence of Tn-C in the stroma of invasion fronts and within tumour cells seems to be related to a more benign disease behaviour with a lower risk of developing metastases.