mSWAT (Skin Tumor Burden, Mycosis Fungoides)
The modified Severity-Weighted Assessment Tool (mSWAT; Olsen and colleagues, J Clin Oncol 2011), which measures SKIN TUMOR BURDEN in mycosis fungoides and Sezary syndrome.
Open the calculator → Runs in your browser. Data leaves only if you deliberately send a problem report from the interactive tool.
Example
- Whether the patient is erythrodermic
- No
- Percent body surface area of "Patch (flat lesion)" (erythrodermic) / "Mild…
- 10 % BSA
- Percent body surface area of "Plaque (raised lesion)" (erythrodermic) /…
- 20 % BSA
- Percent body surface area of "Tumor or ulcer" (erythrodermic) / "Tumor or ulcer"
- 5 % BSA
Result: mSWAT 70 (range 0 to 400).
The tool opens with these values already filled in. Replace them with your own.
What the result means
- Exclusive
- Each square centimeter counts ONCE. The three percentages together cannot exceed 100.
- Vocabulary
- Erythrodermic: patch / plaque / tumor. Nonerythrodermic: mild / moderate infiltration / tumor. Same weights.
- No bands
- NONE published. The threshold is a CHANGE: a 50% or greater reduction from baseline is a partial skin response.
- Scope
- Skin only. Does not stage TNMB; Sezary syndrome is defined by blood this cannot see.
What you enter
- Whether the patient is erythrodermic.
- Percent body surface area of "Patch (flat lesion)" (erythrodermic) / "Mild infiltration" (nonerythrodermic).
- Percent body surface area of "Plaque (raised lesion)" (erythrodermic) / "Moderate infiltration" (nonerythrodermic).
- Percent body surface area of "Tumor or ulcer" (erythrodermic) / "Tumor or ulcer" (nonerythrodermic).
Full field descriptions
- Whether the patient is erythrodermic. REQUIRED: it selects the lesion vocabulary (patch and plaque versus mild and moderate infiltration), though the weights and the arithmetic are identical either way.
- Percent body surface area of "Patch (flat lesion)" (erythrodermic) / "Mild infiltration" (nonerythrodermic). WEIGHT 1. Counted once per square centimeter: the three categories are mutually exclusive and together cannot exceed 100 percent.
- Percent body surface area of "Plaque (raised lesion)" (erythrodermic) / "Moderate infiltration" (nonerythrodermic). WEIGHT 2. Counted once per square centimeter: the three categories are mutually exclusive and together cannot exceed 100 percent.
- Percent body surface area of "Tumor or ulcer" (erythrodermic) / "Tumor or ulcer" (nonerythrodermic). WEIGHT 4. Counted once per square centimeter: the three categories are mutually exclusive and together cannot exceed 100 percent.
How this is calculated
- Formula
- (%BSA x 1) + (%BSA x 2) + (tumor or ulcer %BSA x 4), summed.
- Range
- 0 to 400, NOT 0 to 100. A body wholly covered in tumor scores 4 x 100. Never report it as a %BSA.
- Weights
- Tumor is 4 in mSWAT, was 3 in the original SWAT. Ulcers score with tumors.
Olsen EA, Whittaker S, Kim YH, et al. Clinical end points and response criteria in mycosis fungoides and Sezary syndrome: a consensus statement of the ISCL, the USCLC, and the Cutaneous Lymphoma Task Force of the EORTC. J Clin Oncol. 2011;29(18):2598-2607. Read the source ↗
A reference and educational tool. Not medical, legal, or financial advice, and not a substitute for clinician judgment.