From the Guidelines
Melanoma commonly metastasizes to the lymph nodes, lungs, liver, brain, bone, and skin, with the lymph nodes being the initial site of spread, followed by distant organs such as the lungs and liver, as stated in the ESMO clinical practice guidelines for diagnosis, treatment, and follow-up of cutaneous melanoma 1.
Common Sites of Metastasis
- Lymph nodes: The initial spread of melanoma typically occurs through the lymphatic system to regional lymph nodes, which is why sentinel lymph node biopsies are important for staging, as mentioned in the guidelines for treatment modalities for melanoma metastases 1.
- Lungs: The lungs are the most common site of distant metastasis, followed by the liver, as indicated in the table of treatment modalities for melanoma metastases 1.
- Liver: The liver is another common site of distant metastasis, with treatment options including systemic therapy and consideration of clinical trial participation 1.
- Brain: Brain metastases are particularly concerning and occur in approximately 40-50% of patients with advanced melanoma, with treatment options including surgical removal, stereotactic irradiation, and systemic therapy 1.
- Bone: Bone metastases are also common, with treatment options including radiotherapy and bone-modifying agents 1.
- Skin: Cutaneous or subcutaneous metastases (skin) are also common, with treatment options including surgical removal, T-VEC, and electrochemotherapy 1.
Molecular Mechanisms
The cancer's ability to spread widely is facilitated by various molecular mechanisms, including BRAF mutations (present in about 50% of melanomas) that activate pathways promoting cell survival and proliferation, as discussed in the context of ipilimumab/nivolumab combination therapy 1.
Treatment Options
Treatment options for melanoma metastases vary depending on the site and number of metastases, as well as the presence of symptoms, with a focus on systemic therapy, stereotactic irradiation, and surgical removal, as outlined in the guidelines for treatment modalities for melanoma metastases 1.
From the Research
Melanoma Metastasis
- Melanoma is a highly aggressive cancer with metastatic potential to various locations, including: + Lymph nodes + Lungs + Liver + Brain + Bone 2
- The lungs are the most common site of malignant melanoma metastases after the lymph nodes 2
- Pulmonary metastases from malignant melanoma can present as solitary or multiple solid nodules, sub-solid nodules, or miliary opacities on CT chest, but can also have atypical imaging findings 2
- Other sites of metastasis mentioned in the studies include: + Ocular melanoma + Brain metastases + Liver metastases + Bone metastases 3
Treatment and Management
- The combination of immunotherapy and radiotherapy is a safe therapeutic option for melanoma, with promising results in terms of survival outcomes 3
- Immunotherapy has been revolutionized by the concept of breaking tolerance, with the development of immune checkpoint inhibitors such as anti-CTLA-4 and anti-PD-1/anti-PD-L1 4
- The combination of ipilimumab and nivolumab is a highly active systemic therapy for metastatic melanoma, but can cause significant toxicity 5
- Other treatments mentioned in the studies include: + BRAF inhibitors plus MEK inhibitors for BRAF-mutant melanomas + Oncolytic virus vaccine + Targeted agents + Chemotherapeutics + Radiation therapy 4, 5, 6