Nodal metastases and biomarkers in melanoma

PhD ceremony: Mr. S. Kruijff, 12.45 uur, Aula Academiegebouw, Broerstraat 5, Groningen

Dissertation: Nodal metastases and biomarkers in melanoma

Promotor(s): prof. H.J. Hoekstra

Faculty: Medical Sciences

Melanoma is the most malignant type of skin cancers and causes over 75 % of skin cancer related mortality. In the Netherlands, the total number of new diagnosed melanoma patients is expected to increase from 2400 patients in 2000 to 4800 patients in 2015. After surgical treatment, 20-28% of melanoma patients present with loco-regional recurrence, 26-60% with regional recurrences, and 15-50% with distant metastases. Early detection of lymph node (micro) metastases by means of a sentinel lymph node biopsy is crucial to allow for treatment and improve overall survival. When patients present with palpable nodes, given the heterogeneity in survival, it is suspected that numerous patients have a form of subclinical dissemination, which remains undetected with current imaging methods. Biomarkers could play a role, although their biological significance is little understood. It can be expected that the strongest biological markers are surrogates of key biological events. The studies described in this thesis discuss the use of biomarkers in the treatment of melanoma and the correlation between these biomarkers and the biology of the disease.

The protein S-100B appeared to be the best analyzed biomarker in melanoma. Potentially it can be used to identify high risk stage III melanoma patients who may benefit from adjuvant systemic treatment. We recommend the use of S-100B for stratification of patients with loco regional recurrences in trials testing new adjuvant therapeutics. Since an effective (adjuvant) therapy for loco-regional metastatic and disseminated melanoma was recently introduced, the use of S-100B may alter in the near future.