Melanoma originates in melanocytes, the cells responsible for skin pigment. While less common than other skin cancers, it can spread if not detected and treated early. Stage 3 melanoma means the cancer has advanced beyond the original tumor, typically reaching nearby lymph nodes or manifesting as skin metastases. Despite its advanced nature, treatment progress has improved patient outcomes.
Defining Stage 3 Melanoma
Stage 3 melanoma involves cancer spread from the primary tumor to regional lymph nodes, or the presence of in-transit, satellite, or microsatellite metastases without distant organ spread. In-transit metastases are small tumors over 2 centimeters from the primary melanoma, appearing between the original tumor and the nearest lymph node basin. Satellite metastases are within 2 centimeters of the primary tumor.
The American Joint Committee on Cancer (AJCC) staging system categorizes Stage 3 melanoma into sub-stages: IIIA, IIIB, IIIC, and IIID. These sub-stages reflect increasing tumor burden and influence prognosis. For instance, Stage IIIA indicates a smaller tumor burden in lymph nodes, while Stage IIID indicates more extensive spread or numerous in-transit/satellite metastases.
Doctors determine the stage via physical examination, primary tumor biopsy, and sentinel lymph node biopsy (SLNB) to check for spread. Imaging tests like PET/CT or MRI scans are also used to assess the extent of spread and confirm no distant metastasis.
Treatment Strategies
Treatment for Stage 3 melanoma begins with surgical removal of the primary tumor and affected regional lymph nodes. This procedure, known as wide local excision, removes the primary cancer and a margin of healthy tissue. If sentinel lymph node biopsy reveals cancer cells, a complete lymph node dissection may be performed.
Following surgery, patients receive adjuvant systemic therapies to reduce recurrence risk. Immunotherapy, such as PD-1 inhibitors, works by boosting the body’s immune system to recognize and destroy cancer cells. For patients with a BRAF V600 mutation, targeted therapies using BRAF/MEK inhibitors (e.g., dabrafenib plus trametinib) are an option. These medications block proteins that fuel cancer growth.
Radiation therapy is also considered for situations with a high risk of local recurrence after surgery, or for involved lymph nodes. Treatment choice is individualized, depending on the melanoma’s sub-stage, tumor characteristics (BRAF mutation status or ulceration), and the patient’s overall health. Clinical guidelines guide personalized treatment plans.
Prognosis and Long-Term Outcomes
While “cure” is challenging to apply definitively to advanced cancers, many with Stage 3 melanoma achieve long-term remission, meaning no detectable disease. Survival statistics provide an estimate of outcomes for groups of patients. For Stage 3 melanoma, the overall 5-year survival rate is approximately 63.6%.
This rate varies significantly based on sub-stage and other factors. For example, the 5-year survival rate for Stage IIIA melanoma can be as high as 93%, while for Stage IIID, it may be around 32%. Factors influencing prognosis include the number of involved lymph nodes, whether the primary tumor was ulcerated (skin surface broken), BRAF mutation presence, and serum LDH levels.
Recurrence risk remains even after successful initial treatment, which underscores the need for ongoing surveillance. These statistics represent averages, and individual outcomes can differ considerably.
Ongoing Management and Monitoring
After initial treatment, ongoing management and monitoring are important for individuals with Stage 3 melanoma to detect any potential recurrence early. Regular follow-up appointments include physical examinations and comprehensive skin checks performed by a dermatologist. Imaging scans, such as PET/CT or MRI, are also used to monitor for signs of recurrence, especially for patients with a higher risk.
Patients are encouraged to perform monthly self-skin exams to identify new or changing moles or lesions. Lifelong sun protection is important to reduce the risk of developing new melanomas. Managing long-term treatment side effects is another aspect of ongoing care, which may involve supportive therapies. For some patients, participating in clinical trials offers access to cutting-edge therapies and contributes to advancements in melanoma treatment.