Imaging Biomarker Can Help To Assess Glioma Malignancy

CHICAGO — Measurement of cerebral blood flow volume in a patient with glioma is a sensitive predictor of disease stability or progression, according to Dr. Meng Law, who presented his findings at the annual meeting of the American Society of Neuroradiology.

Using dynamic susceptibility contrast perfusion magnetic resonance imaging (DSC-MRI), Dr. Law found that gliomas with a high relative cerebral blood volume (rCBV) showed significantly more rapid time to progression than did gliomas with a low rCBV. This information gained at the time of diagnosis can impact treatment decisions, including the extent of neurosurgical resection, or the choice of postoperative radiation or chemotherapy protocols.

This 10-year, retrospective study included 189 patients with histologically proved gliomas: low-grade astrocytomas (28), low-grade oligodendrogliomas (14), low-grade oligoastrocytomas (11), anaplastic astrocytomas (72), anaplastic oligoastrocytomas (12), and glioblastoma multiforme (52).

Patients underwent DSC-MRI, and measurements of rCBV were obtained by choosing the highest regional intratumoral rCBV after excluding large intratumoral vessels. Patients were followed up clinically and with MRI (median follow-up 3.2 years).

Dr. Law, currently of Mount Sinai Medical Center, New York, conducted this research while on the faculty of New York University.

Patients who progressed had a mean rCBV of 4.84 (n=130) and for patients who died the mean value was 3.82 (n=36), values that were much higher than in those who showed a complete response (1.41, n=4) or who had stable disease (2.36, n=41). P values from logistic regression demonstrated that age and rCBV were significant predictors of disease progression and death.

Patients with higher rCBV scores showed more rapid time to progression (TTP), as seen in the image, below. Those patients with an rCBV greater than 1.75 had a mean TTP of 265 days, compared with 3,585 days for those with an rCBV less than 1.75.

These values were derived from Kaplan-Meier Progression Free Survival curves. The 1.75 threshold for rCBV has a sensitivity of about 90% for distinguishing low-grade from high-grade tumors, said Dr. Law.

DSC-MRI is a technique that can provide physiologic information about vascular endothelial proliferation, vascular density, and angiogenesis. Since vascular proliferation is an important factor in the biology of gliomas, Dr. Law said, it is not surprising that DSC-MRI can provide an accurate means of characterizing tumor biology.

According to Dr. Law, while histopathology is the standard reference for determining glioma tumor biology and making prognostic decisions, histopathology has significant limitations. These include sampling errors, inter- and intraobserver variability, and dynamic changes as the tumor progresses.

Since patients with misclassified gliomas may not receive optimum treatment, Dr. Law suggested that measuring cerebral blood volume may be as sensitive, or even more sensitive, a predictor than pathology when assessing glioma outcomes.

He is investigating this further in a multicenter study using perfusion in predicting patient outcome; the study is being funded by the nonprofit Accelerate Brain Cancer Cure in Washington.

Imaging shows disease progression over a 6-month period in a man with a pathology-proven low-grade astrocytoma but a high baseline relative cerebral blood volume (rCBV). Dr. Law said that while histopathology is the standard reference for determining glioma biology and making prognostic decisions, it has limitations. Images courtesy Dr. Meng Law

CHICAGO — Measurement of cerebral blood flow volume in a patient with glioma is a sensitive predictor of disease stability or progression, according to Dr. Meng Law, who presented his findings at the annual meeting of the American Society of Neuroradiology.

Using dynamic susceptibility contrast perfusion magnetic resonance imaging (DSC-MRI), Dr. Law found that gliomas with a high relative cerebral blood volume (rCBV) showed significantly more rapid time to progression than did gliomas with a low rCBV. This information gained at the time of diagnosis can impact treatment decisions, including the extent of neurosurgical resection, or the choice of postoperative radiation or chemotherapy protocols.

This 10-year, retrospective study included 189 patients with histologically proved gliomas: low-grade astrocytomas (28), low-grade oligodendrogliomas (14), low-grade oligoastrocytomas (11), anaplastic astrocytomas (72), anaplastic oligoastrocytomas (12), and glioblastoma multiforme (52).

Patients underwent DSC-MRI, and measurements of rCBV were obtained by choosing the highest regional intratumoral rCBV after excluding large intratumoral vessels. Patients were followed up clinically and with MRI (median follow-up 3.2 years).

Dr. Law, currently of Mount Sinai Medical Center, New York, conducted this research while on the faculty of New York University.

Patients who progressed had a mean rCBV of 4.84 (n=130) and for patients who died the mean value was 3.82 (n=36), values that were much higher than in those who showed a complete response (1.41, n=4) or who had stable disease (2.36, n=41). P values from logistic regression demonstrated that age and rCBV were significant predictors of disease progression and death.

Patients with higher rCBV scores showed more rapid time to progression (TTP), as seen in the image, below. Those patients with an rCBV greater than 1.75 had a mean TTP of 265 days, compared with 3,585 days for those with an rCBV less than 1.75.

These values were derived from Kaplan-Meier Progression Free Survival curves. The 1.75 threshold for rCBV has a sensitivity of about 90% for distinguishing low-grade from high-grade tumors, said Dr. Law.

DSC-MRI is a technique that can provide physiologic information about vascular endothelial proliferation, vascular density, and angiogenesis. Since vascular proliferation is an important factor in the biology of gliomas, Dr. Law said, it is not surprising that DSC-MRI can provide an accurate means of characterizing tumor biology.

According to Dr. Law, while histopathology is the standard reference for determining glioma tumor biology and making prognostic decisions, histopathology has significant limitations. These include sampling errors, inter- and intraobserver variability, and dynamic changes as the tumor progresses.

Since patients with misclassified gliomas may not receive optimum treatment, Dr. Law suggested that measuring cerebral blood volume may be as sensitive, or even more sensitive, a predictor than pathology when assessing glioma outcomes.

He is investigating this further in a multicenter study using perfusion in predicting patient outcome; the study is being funded by the nonprofit Accelerate Brain Cancer Cure in Washington.

Imaging shows disease progression over a 6-month period in a man with a pathology-proven low-grade astrocytoma but a high baseline relative cerebral blood volume (rCBV). Dr. Law said that while histopathology is the standard reference for determining glioma biology and making prognostic decisions, it has limitations. Images courtesy Dr. Meng Law

CHICAGO — Measurement of cerebral blood flow volume in a patient with glioma is a sensitive predictor of disease stability or progression, according to Dr. Meng Law, who presented his findings at the annual meeting of the American Society of Neuroradiology.

Using dynamic susceptibility contrast perfusion magnetic resonance imaging (DSC-MRI), Dr. Law found that gliomas with a high relative cerebral blood volume (rCBV) showed significantly more rapid time to progression than did gliomas with a low rCBV. This information gained at the time of diagnosis can impact treatment decisions, including the extent of neurosurgical resection, or the choice of postoperative radiation or chemotherapy protocols.

This 10-year, retrospective study included 189 patients with histologically proved gliomas: low-grade astrocytomas (28), low-grade oligodendrogliomas (14), low-grade oligoastrocytomas (11), anaplastic astrocytomas (72), anaplastic oligoastrocytomas (12), and glioblastoma multiforme (52).

Patients underwent DSC-MRI, and measurements of rCBV were obtained by choosing the highest regional intratumoral rCBV after excluding large intratumoral vessels. Patients were followed up clinically and with MRI (median follow-up 3.2 years).

Dr. Law, currently of Mount Sinai Medical Center, New York, conducted this research while on the faculty of New York University.

Patients who progressed had a mean rCBV of 4.84 (n=130) and for patients who died the mean value was 3.82 (n=36), values that were much higher than in those who showed a complete response (1.41, n=4) or who had stable disease (2.36, n=41). P values from logistic regression demonstrated that age and rCBV were significant predictors of disease progression and death.

Patients with higher rCBV scores showed more rapid time to progression (TTP), as seen in the image, below. Those patients with an rCBV greater than 1.75 had a mean TTP of 265 days, compared with 3,585 days for those with an rCBV less than 1.75.

These values were derived from Kaplan-Meier Progression Free Survival curves. The 1.75 threshold for rCBV has a sensitivity of about 90% for distinguishing low-grade from high-grade tumors, said Dr. Law.

DSC-MRI is a technique that can provide physiologic information about vascular endothelial proliferation, vascular density, and angiogenesis. Since vascular proliferation is an important factor in the biology of gliomas, Dr. Law said, it is not surprising that DSC-MRI can provide an accurate means of characterizing tumor biology.

According to Dr. Law, while histopathology is the standard reference for determining glioma tumor biology and making prognostic decisions, histopathology has significant limitations. These include sampling errors, inter- and intraobserver variability, and dynamic changes as the tumor progresses.

Since patients with misclassified gliomas may not receive optimum treatment, Dr. Law suggested that measuring cerebral blood volume may be as sensitive, or even more sensitive, a predictor than pathology when assessing glioma outcomes.

He is investigating this further in a multicenter study using perfusion in predicting patient outcome; the study is being funded by the nonprofit Accelerate Brain Cancer Cure in Washington.

Imaging shows disease progression over a 6-month period in a man with a pathology-proven low-grade astrocytoma but a high baseline relative cerebral blood volume (rCBV). Dr. Law said that while histopathology is the standard reference for determining glioma biology and making prognostic decisions, it has limitations. Images courtesy Dr. Meng Law