Brain Metastasis Velocity (BMV) Model

BMV Calculator

Number of New Brain Metastases

Time Between MRIs

months

Brain Metastasis Velocity: –

new mets/year

Awaiting input

Enter number of new mets and months between MRIs.

Calculates rate of distant brain failure after stereotactic radiosurgery for brain metastasis.

Why Use

Stratifying patients into high and low BMV categories can allow providers to better counsel patients on their risks of requiring additional treatments in the future, such additional SRS or whole brain radiation therapy.

When to Use

Use for patients with any primary cancer who have developed a distant brain failure (new brain metastasis) after upfront stereotactic radiosurgery (SRS). Not appropriate for use in patients who have had prior whole brain radiation therapy.

Formula

BMV, per year = x / y, where the variables are as follows: x = number of new brain metastases since initial SRS y = total time interval between initial SRS and appearance of new brain metastases, in years

Pearls / Pitfalls

Developed to predict outcomes at the time of salvage treatment after upfront SRS. Correlates with overall survival, neurologic death, and time to additional salvage treatments by placing patients into low, intermediate, and high risk groups. Primary cancers with the largest representation in the study were breast, lung, RCC, and melanoma.

Management

For patients with low BMV (scores <4), localized therapy (e.g. SRS) might be most appropriate. Counseling patients with high BMV (scores >13) that there is an increased risk of needing additional therapies in the future, should a localized approach be considered, is an important part of management.

More Information

Interpretation: BMV Risk group Median overall survival <4 Low 12.4 months 4-13 Intermediate 8.2 months >13 High 4.3 months From Farris et al (2017) .