As a primary treatment, radiotherapy (radiotherapy; radiatio) is given for malignant melanoma only when surgery cannot be performed.
Radiotherapy of the primary tumor is indicated for [S3 guideline]:
- Lentigo-maligna melanomas that are not suitable for surgical therapy because of extension, location, and/or age of the patient.
- Inoperable R1- or R2-resected primary tumors (microscopically or macroscopically proven residual tumor/residual tumor) with the aim of local control.
- Desmoplastic malignant melanomas (DMM) that were not resected with sufficient safety margin (< 1 cm or R1/R2), postoperative radiotherapy should be performed to ensure local tumor control. Note: DMM have a high recurrence rate (recurrence of the tumor).
Furthermore, radiotherapy is indicated for:
- Regional lymph node metastases or in-transit metastases when surgical therapy is not possible (local radiotherapy).
- Multiple bone and brain metastases (combination therapy of radiotherapy and CTLA-4 blocker ipilimumab).
Postoperative adjuvant radiotherapy (radiotherapy; 50-60 Gy in conventional fractionation).
- To improve tumor control of the lymph node station at.
- Three or more lymph nodes affected.
- Capsular rupture
- Metastasis diameter > 3 cm or
- Recurrence (recurrence of the disease).
Adjuvant radiotherapy after lymphadenectomy (lymph node removal) [S3 guideline]:
- To improve tumor control of the lymph node station, postoperative (after surgery) adjuvant radiotherapy should be given if at least one of the following criteria is present:
- 3 affected lymph nodes,
- Capsular rupture,
- Lymph node metastasis (daughter tumors in a lymph node) > 3 cm,
- Lymphogenic recurrence (recurrence of the tumor in the lymphatic system).
Radiotherapy of distant metastases [S3 guideline].
- Conventional fractionation regimens show equal efficacy in terms of local tumor control compared with higher single doses (> 3 Gy).
- In cases of bone metastasis (osseous metastasis), radiation therapy should be performed to improve clinical symptoms.
- For multiple symptomatic brain metastases (daughter tumors in the brain), palliative irradiation (“irradiation to relieve symptoms”) of the whole brain should be offered if the expected lifetime is longer than 3 months.
Currently, the combination of radiotherapy and hyperthermia is being studied.
Further notes
- The median overall survival of melanoma patients with brain metastases (daughter tumors in the brain) and modern drug therapy (BRAF, CTLA-4, and PD-1 inhibitors) and additional stereotactic radiotherapy (radiotherapy using a computer-assisted targeting system that allows precise localization control and very accurate radiation) or surgery was just under 15 months.
- In patients with up to three locally treated brain metastases (daughter tumors in the brain), adjuvant whole-brain radiation (as a supportive measure) did not result in clinical benefit (defined with the primary or secondary end points of this study).CONCLUSION: Adjuvant whole-brain radiation should be avoided after surgical or radiosurgical treatment of brain metastases.
- In the presence of choroidal and iris melanoma (eye tumors), which is not suitable for brachytherapy ( short-distance radiotherapy), proton therapy should be used.
