• HLA-DQ;
  • Ki-67;
  • multivariate analysis;
  • primary malignant melanoma;
  • prognosis;
  • tumour thickness

Background Several clinical and histological factors of primary melanomas comprise a relatively large quantity of prognostic information.

Objective To find immunohistochemical markers that can improve the prognostic accuracy achieved by factors that are available without extra laboratory work, i.e. mitotic rate, tumour thickness, ulceration, localization, gender and age.

Methods Immunohistochemical markers were determined on frozen sections. Univariate and multivariate Cox regression analyses were performed after 5–10 years follow-up.

Results Seven immunohistochemical markers were related to disease-free and overall survival in univariate Cox regression analysis: Ki-67, human leucocyte antigen (HLA) -DQ, HLA-DP, Muc 18, A-10-33, transferrin receptor, and H-2-8-10. Only Ki-67 (n = 399) and HLA-DQ (n = 452) retained prognostic significance when evaluated in multivariate analyses in several models together with tumour thickness alone and with tumour thickness, gender, mitotic rate, age, localization and ulceration.

Conclusions Ki-67 and HLA-DQ may be useful for risk assessments in primary melanomas.