BackgroundSentinel lymph node biopsy is an appropriate method to assess lymphatic involvement in cutaneous melanoma. We collated clinical and histo-pathological parameters of primary tumours to assess their predictive value of sentinel lymph node involvement.Patients and methodsFactors such as age, gender, histology subtype, site, Breslow index, lesion size, and the presence of ulceration, signs of regression, lympho-vascular invasion and/or inflammatory infiltration of the primary lesion were collated from 142 patients diagnosed with cutaneous melanoma. During the scheduled surgery, a selective sentinel lymph node biopsy was taken. The procedure was successful in terms of localisation with scintigraphy, detection and surgical removal. Univariate and multivariate statistical analyses were applied to the variables in relation to the sentinel lymph node biopsy results.ResultsThere were significant differences with respect to size (p=0.046), the presence of ulceration in the primary lesion (p=0.0146), the Breslow index (p=0.0001) and lympho-vascular invasion in the primary lesion (p=0.00005). Logistic regression showed an independent predictive value for sentinel lymph node involvement.ConclusionsThe data indicate that, apart from Breslow index, the presence of lymphatic invasion in the primary tumour, the size of the melanoma, and the presence of ulceration are independent factors predictive of a positive result of selective sentinel lymph node biopsy in cutaneous melanoma. Although prospective studies are still awaited, these variables need to be taken into account when such biopsies are proposed, even with less thick tumours.