Neurology · LIVE

Brain metastasis velocity

Compute Farris 2017 brain metastasis velocity as new_brain_metastases / years_since_first_srs and report the published low, intermediate, or high group plus that group's median overall survival after initial distant brain failure.

LIVE $0.005 USDC GET /api/calc/bmv

Markdown: /docs/bmv.md · Canonical: https://magentlab.com/docs/bmv

Not a medical device. Not a diagnosis, dose, or listing recommendation.

What it computes

Compute Farris 2017 brain metastasis velocity as new_brain_metastases / years_since_first_srs and report the published low, intermediate, or high group plus that group's median overall survival after initial distant brain failure.

When to use

When an agent already has the cumulative number of new brain metastases since first SRS and the years since first SRS, and must not floor BMV, use time since last SRS, or treat velocity as a diagnosis.

When not to use

• Not a medical device. magent does not count metastases on imaging or diagnose distant brain failure.
• Farris 2017 BMV is new_brain_metastases / years_since_first_srs, rounded to 1 decimal. magent does not floor or round down BMV (that is NRG-BN009, not Farris).
• Years since first SRS only. This tool does not use time since last SRS.
• Not a diagnosis. Median OS is the published Farris 2017 group median after initial distant brain failure (low 12.4, intermediate 8.2, high 4.3 months). magent does not return confidence intervals or hazard ratios as scored outputs.

Formula

bmv = new_brain_metastases / years_since_first_srs

Citation

Title

Brain Metastasis Velocity: A Novel Prognostic Metric Predictive of Overall Survival and Freedom From Whole-Brain Radiation Therapy After Distant Brain Failure Following Upfront Radiosurgery Alone

Authors

Farris M, McTyre ER, Cramer CK, et al.

Source

Int J Radiat Oncol Biol Phys. 2017 May 1;98(1):169-175

DOI

10.1016/j.ijrobp.2017.01.201

Worked example

Also searched as

• brain metastasis velocity
• BMV
• Farris BMV
• distant brain failure velocity
• new brain metastases per year
• SRS brain metastasis velocity
• brain mets velocity

Try

Opens the live endpoint. Unpaid browser requests show the paywall; agents should send Accept: application/json.

/api/calc/bmv?new_brain_metastases=3&years_since_first_srs=1

Full URL: https://api.magentlab.com/api/calc/bmv?new_brain_metastases=3&years_since_first_srs=1

Call

Expect HTTP 402 until you retry with PAYMENT-SIGNATURE. Incomplete query params return HTTP 400 before any quote or charge.

curl -i -H "Accept: application/json" "https://api.magentlab.com/api/calc/bmv?new_brain_metastases=3&years_since_first_srs=1"

Parameters

Bulk (POST)

POST the same path with a JSON items array. The first item is the GET unit; each additional item is $0.002. Invalid items return HTTP 400 before settlement.

POST /api/calc/bmv Max 25 unit_amount + extra_item_amount * (n - 1) extra $0.002 PREVIEW

• 1 to 25 items. Each item uses the same keys as the GET query parameters.
• POST of 1 item costs the same as GET. Lists longer than 25: chunk into multiple POSTs. Extra items still execute; do not pad dummy rows.
• The first invalid item fails the whole request (index in the 400 JSON). You are not charged.
• HTTP 200 is {count, path, items}. Each items[i] is the GET 200 body for that row.
• Catalog misses (empty matches, found=false) stay paid 200s inside that slot.
• x402 resource URL is this path plus n and body_sha256. Browsers that prefer text/html get the same paywall as GET; Pay retries POST with the same items.

Example request (fixture)

{
  "items": [
    {
      "new_brain_metastases": "3",
      "years_since_first_srs": "1"
    },
    {
      "new_brain_metastases": "3",
      "years_since_first_srs": "1"
    }
  ]
}

Open bulk paywall →

Opens a two-item fixture on the API host. Unpaid browsers get the same MetaMask paywall as GET; Pay retries POST with those items.

Example 200 (fixture)

{
  "count": 2,
  "path": "/api/calc/bmv",
  "items": [
    {
      "disclaimer": "Not a medical device. Deterministic published-formula or published-code output for autonomous agents. A licensed clinician remains responsible for patient care and billing submissions.",
      "citation": {
        "authors": "Farris M, McTyre ER, Cramer CK, et al.",
        "doi": "10.1016/j.ijrobp.2017.01.201",
        "id": "farris-2017",
        "pmid": "28586952",
        "source": "Int J Radiat Oncol Biol Phys. 2017 May 1;98(1):169-175",
        "title": "Brain Metastasis Velocity: A Novel Prognostic Metric Predictive of Overall Survival and Freedom From Whole-Brain Radiation Therapy After Distant Brain Failure Following Upfront Radiosurgery Alone"
      },
      "formula": "bmv",
      "formula_expression": "bmv = new_brain_metastases / years_since_first_srs",
      "risk_group": "low",
      "bmv": 3.0,
      "median_os_months": 12.4,
      "new_brain_metastases": 3,
      "years_since_first_srs": 1.0
    },
    {
      "disclaimer": "Not a medical device. Deterministic published-formula or published-code output for autonomous agents. A licensed clinician remains responsible for patient care and billing submissions.",
      "citation": {
        "authors": "Farris M, McTyre ER, Cramer CK, et al.",
        "doi": "10.1016/j.ijrobp.2017.01.201",
        "id": "farris-2017",
        "pmid": "28586952",
        "source": "Int J Radiat Oncol Biol Phys. 2017 May 1;98(1):169-175",
        "title": "Brain Metastasis Velocity: A Novel Prognostic Metric Predictive of Overall Survival and Freedom From Whole-Brain Radiation Therapy After Distant Brain Failure Following Upfront Radiosurgery Alone"
      },
      "formula": "bmv",
      "formula_expression": "bmv = new_brain_metastases / years_since_first_srs",
      "risk_group": "low",
      "bmv": 3.0,
      "median_os_months": 12.4,
      "new_brain_metastases": 3,
      "years_since_first_srs": 1.0
    }
  ]
}

Response

Example JSON

Machine form of the same example. Frozen fixture. Not a live lookup.

{
  "disclaimer": "Not a medical device. Deterministic published-formula or published-code output for autonomous agents. A licensed clinician remains responsible for patient care and billing submissions.",
  "citation": {
    "authors": "Farris M, McTyre ER, Cramer CK, et al.",
    "doi": "10.1016/j.ijrobp.2017.01.201",
    "id": "farris-2017",
    "pmid": "28586952",
    "source": "Int J Radiat Oncol Biol Phys. 2017 May 1;98(1):169-175",
    "title": "Brain Metastasis Velocity: A Novel Prognostic Metric Predictive of Overall Survival and Freedom From Whole-Brain Radiation Therapy After Distant Brain Failure Following Upfront Radiosurgery Alone"
  },
  "formula": "bmv",
  "formula_expression": "bmv = new_brain_metastases / years_since_first_srs",
  "risk_group": "low",
  "bmv": 3.0,
  "median_os_months": 12.4,
  "new_brain_metastases": 3,
  "years_since_first_srs": 1.0
}

Client errors (HTTP 400)

Invalid params return 400 without charge. Shared HTTP 402 and 503 meanings: Payments.

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Payment

Unpaid requests return HTTP 402 even if query parameters or POST items are missing or invalid, so CDP and agents can index the path. After a PAYMENT-SIGNATURE, invalid params return HTTP 400 JSON before settlement. magent does not charge. Fix the params, then request a new 402 quote for that complete URL. Catalog misses (empty matches, found=false) are valid paid 200s. Unpaid valid requests return HTTP 402 with a base64 PAYMENT-REQUIRED header. HTTP 503 is not a new quote: retry the same PAYMENT-SIGNATURE. Full handshake and shared payment errors: Payments. Stdio MCP: /docs/mcp.

Guarantees

• HTTP 402 is unpaid, including a missing query. After PAYMENT-SIGNATURE, invalid parameters return HTTP 400 before settlement. You are not charged. HTTP 402 never includes the tool JSON.
• exact: settlement finishes before the tool (paymentFlow upfront). batch-settlement: verify/deposit before the tool; chargedCumulativeAmount commits after HTTP 2xx. Uncertain or failed settlement fails closed (HTTP 503). Retry the same PAYMENT-SIGNATURE.
• HTTP 402 is unpaid only. Do not sign a second authorization because of a 503.
• Execution is timeout-bounded and concurrency-capped.
• Calculator inputs are stored encrypted for allowlisted operators (Magent Console). They are not in public logs, SSH lookups, catalog, or rollups. Request logs store path without query.