1. What is the MSK Nomogram?

The MSK (Memorial Sloan Kettering) nomogram estimates the risk of sentinel lymph node positivity in melanoma patients based on tumor thickness, ulceration status, and patient age.

2. How Does the Calculator Work?

The calculator uses the MSK nomogram:

Where:

• Thickness — Tumor thickness in millimeters (mm)
• Ulceration — Presence or absence of ulceration
• Age — Patient age in years

Explanation: The nomogram accounts for the relationship between tumor characteristics and the likelihood of lymph node metastasis.

3. Importance of Sentinel Lymph Node Risk Assessment

Details: Accurate risk assessment helps guide decisions about sentinel lymph node biopsy, which is important for staging and prognosis in melanoma patients.

4. Using the Calculator

Tips: Enter tumor thickness in mm, select ulceration status, and enter age in years. All values must be valid (thickness > 0, age between 1-120).

5. Frequently Asked Questions (FAQ)

Q1: What is considered a high risk result?
A: Generally, risk >10% may warrant consideration for sentinel lymph node biopsy, but clinical judgment is essential.

Q2: How accurate is this nomogram?
A: The MSK nomogram has been validated in multiple studies with good predictive accuracy (AUC ~0.75).

Q3: Are there other factors that affect lymph node risk?
A: Yes, factors like mitotic rate, lymphovascular invasion, and tumor location may also influence risk.

Q4: Should this replace clinical judgment?
A: No, this is a decision-support tool that should be used in conjunction with clinical evaluation.

Q5: What's the minimum thickness for considering SLNB?
A: Current guidelines suggest considering SLNB for tumors ≥0.8mm, or ≥0.6mm with other risk factors.