Stage III melanoma, a heterogeneous group of patients
Stage III melanoma, a heterogeneous group of patients
Melanoma is a well-known type of skin cancer in Australia and is becoming more common in the Netherlands. This thesis describes several studies, conducted in Australia, which guide diagnostic and treatment decisions in patients with regional metastases (stage III melanoma).
There is debate about further treatment of patients with minimal metastasis in the sentinel node (the lymph node receiving lymph fluid directly from the original tumor). In the first part of this thesis, all lymph nodes in the nodal region of a group of patients with such minimal metastasis were microscopically re-examined with special immunostaining. The risk of metastasis to non-sentinel lymph nodes appears to be low, however the survival of patients appears to be much worse than expected.
The next part addresses the role of imaging prior to subsequent treatment. A PET/CT scan in people with metastases in lymphatic vessels appears to be useful, due to frequent further metastases. An MRI scan of the brain appears unnecessary. In patients with microscopic metastases in regional lymph nodes, additional PET/CT scanning may give an incorrect result. As such, we urge caution.
The final part involves radiation therapy after lymph node surgery. The added value of this treatment is under debate if drug therapy is also available. A shorter radiation schedule with higher doses per session appears to be just as effective as the more common standard (lower dose) radiation schedule. Additionally, patients with recurrent metastases in the same lymph node field appear to benefit from additional radiation therapy after surgery.