Who needs adjuvant therapy in stage III melanoma?

This thesis aimed to improve surgical treatment of patients with stage III melanoma. These patients, who suffer from lymph node metastasis, were treated by surgery alone in the last few decades. While this was sufficient for a significant number of patients, a large number recurred and died from distant metastases. Recently, effective adjuvant systemic treatments were discovered that decrease the chance of relapse and improve survival. However, these treatments can be toxic and are very expensive. Since not all patients have the same risk of relapse, accurate risk prediction and patient selection for adjuvant therapy is important. We mainly focused on finding prognostic factors for survival in stage III melanoma. We show that the amount of tumor in the sentinel lymph node can differentiate between excellent and worse survival in stage IIIA melanoma patients, allowing patient selection for adjuvant treatment. Also, in these patients, completion lymph node dissection does not significantly add staging information and can be omitted. In stage IIIB melanoma, medium-risk patients, a subgroup with excellent survival can be identified that could be spared adjuvant treatment. This is not the case for stage IIIC melanoma patients, who should all be treated with adjuvant therapy. In conclusion, this thesis shows that risk prediction in stage III melanoma can be further optimized by using combinations of known prognostic criteria, and using sentinel node tumor burden if possible. This allows better patient selection for adjuvant therapy, reducing unnecessary toxicity and costs.