Prognostic value of beta 1 integrin expression in metastatic melanoma

The expression of integrin-type cell adhesion receptors is frequently chang ed in malignant transformation. Despite their important role in cancer cell behaviour, the value of integrins as prognostic markers is mostly unknown. We have examined the expression of beta 1 integrins in 38 metastatic melan omas obtained from 27 patients treated with combined chemoimmunotherapy, On the basis of beta 1 integrin expression, the melanoma samples were divided into two groups: beta 1-negative tumours (<10% beta 1 integrin immunostain ed cells) and beta 1-positive tumours (with greater than or equal to 10% po sitive cells), Patients with beta 1-positive tumours (n=15) had significant ly longer disease-free survival (median 38 versus 7 months, P < 0.0001) and overall survival (median 70 versus 23 months, P = 0.0001) evaluated after the diagnosis of primary disease compared with patients with beta 1-negativ e metastases (n = 11). Moreover, the survival of the patients with beta 1-p ositive tumours after the initiation of chemoimmunotherapy was significantl y prolonged (median 18 versus 9 months, P = 0.017). The independent nature of beta 1 integrin expression as a significant prognostic factor for surviv al after therapy was confirmed using Cox's multivariate analysis (P = 0.014 ), Our results indicate that the expression of pi integrins might have some major tumour growth regulatory role and can be used as a predictor for pro gnosis in patients with metastatic melanoma. (C) 2000 Lippincott Williams & Wilkins.