What does positive surgical margins mean for Melanoma

Understanding Positive Surgical Margins in Melanoma

Great question—this is an important concept that directly affects your treatment plan. Let me explain what this means and why it matters.

What Are Surgical Margins?

When a surgeon removes a melanoma tumor, they don't just remove the visible cancer. They also remove a border of normal-looking skin around it, called the surgical margin. This extra tissue acts as a safety zone to catch any cancer cells that might have spread beyond what's visible to the eye.

What "Positive" Margins Mean

Positive margins means that when the pathologist (a doctor who examines tissue under a microscope) looked at the removed tissue, they found cancer cells right at the edge of what was removed. In other words, the cancer extended all the way to the border of the surgical specimen—suggesting that cancer cells may have been left behind in your body.

This is different from negative margins, which means the pathologist found normal, cancer-free tissue all around the tumor, confirming the surgeon got it all out.

Why This Matters for Melanoma

According to the NCCN Guidelines for Patients: Melanoma (2025), positive margins indicate that additional treatment is typically needed. The guidelines specifically address this situation:

For resectable disease (cancer that can be surgically removed), the recommended approach includes:

• Re-excision surgery — going back in to remove more tissue from that area to achieve clear margins
• Systemic therapy (immunotherapy or targeted therapy) to treat any cancer cells that may have spread
• T-VEC/intralesional therapy — a specialized injection treatment delivered directly into the area

What Happens Next

Your oncologist will likely recommend one or more of these approaches:

1. Additional surgery to remove more tissue and achieve negative margins
2. Adjuvant (follow-up) therapy such as:
   • Nivolumab or Pembrolizumab (checkpoint inhibitors that boost your immune system)
   • Dabrafenib/trametinib (if you have a BRAF mutation)
   • Observation with close monitoring

Questions to Ask Your Care Team

• What size margins did the surgeon achieve, and why are they considered positive?
• Do I need another surgery to re-excise the area?
• What systemic therapy do you recommend for my specific situation?
• Do I need genetic testing for BRAF mutations to guide treatment decisions?
• How will we monitor for recurrence after treatment?

Key Takeaway

Positive margins don't mean your cancer is incurable—it means your care team has identified that additional treatment is needed to reduce the risk of recurrence. The NCCN Guidelines provide clear, evidence-based treatment pathways for this situation, and modern melanoma treatments are quite effective.

This information is for educational purposes only. Always consult your healthcare team for personalized medical advice and decisions.