1. What is the MIA Model?

The MIA (Melanoma Institute Australia) model estimates melanoma risk based on tumor thickness, ulceration status, and mitotic rate. It provides a more accurate assessment of recurrence risk than traditional staging alone.

2. How Does the Calculator Work?

The calculator uses the MIA model equation:

Where:

• Thickness — Tumor thickness in millimeters (Breslow depth)
• Ulceration — Presence or absence of tumor ulceration
• Mitotic Rate — Number of mitoses per square millimeter

Explanation: The equation accounts for the known prognostic factors in melanoma, with different weights assigned to each factor based on clinical studies.

3. Importance of Risk Calculation

Details: Accurate risk estimation is crucial for determining appropriate follow-up schedules, considering adjuvant therapy, and counseling patients about their prognosis.

4. Using the Calculator

Tips: Enter tumor thickness in mm (measured pathologically), select ulceration status, and enter mitotic rate per mm². All values must be valid (thickness > 0, mitotic rate ≥ 0).

5. Frequently Asked Questions (FAQ)

Q1: Why use the MIA model instead of AJCC staging alone?
A: The MIA model provides more individualized risk assessment by incorporating mitotic rate and providing continuous rather than categorical risk estimates.

Q2: What are the risk categories?
A: Risk is typically categorized as low (<10%), intermediate (10-30%), and high (>30%), though clinical context is important.

Q3: How is mitotic rate determined?
A: Mitotic rate is counted in the dermal part of the tumor in the most mitotically active area (per mm²).

Q4: Are there limitations to this model?
A: The model may be less accurate for very thin or very thick melanomas, and doesn't account for all known prognostic factors like lymph node status.

Q5: Should this be used for treatment decisions?
A: Risk estimates should be combined with clinical assessment and discussion with a melanoma specialist when making treatment decisions.