Whole brain radiotherapy for poor prognosis patients with brain metastases: predictably poor results Neil C.

Over 170,000 cases of metastatic brain tumors are diagnosed in the United States each year; and the length of survival for patients with brain metastases is often quite limited, ranging from a few weeks to several months.¹ The Radiation Therapy Oncology Group (RTOG) Recursive Partitioning Analysis (RPA) and the Graded Prognostic Assessment (GPA) are 2 prognostic indices that have been validated to predict survival and guide the treatment of these patients.^2-5 The RPA and GPA indices were formulated by comparing survival to patient and tumor characteristics compiled from RTOG brain metastasis treatment protocols spanning greater than 3 decades. The RPA has 3 classes of patients enumerated as “I”, “II”, and “III,” with class I patients having the longest predicted survival and class III patients having the worst prognosis. The RPA classes are based upon factors that include patient age and Karnofsky Performance Status (KPS) as well as control of the primary tumor and evidence of extra-cranial metastases (Table 1).² The GPA has 4 classes of patients with a score that may be considered analogous to a grade point average achieved by students in school. The classes are arranged into 4 groupings, which are divided from best to worst prognosis as follows: 3.5 to 4.0, 3.0, 1.5 to 2.5, and 0.0 to 1.0. The GPA employs criteria similar to but slightly different from those used in the RPA, estimating survival by patient age and performance status as well as the number of brain metastases and evidence of extracranial metastases (Table 2).⁴

Treatment options for patients with brain metastases include surgery, stereotactic radiosurgery (SRS), whole brain radiation therapy (WBRT), supportive measures such as corticosteroids, or a combination of these modalities. The survival of the worst prognosis brain metastases patients treated with WBRT and steroids is estimated by the RPA and GPA tools to be 2.3 months and 2.6 months, respectively.^2,4 As noted above, the patient data from which the RPA and GPA indices were created included patients treated on clinical trials. This could have resulted in the selection of patients more fit than average patients and lead to an overestimation of survival when applied to all patients. The clinical trial data used were drawn from over 3 decades, during which supportive care and chemotherapy treatments improved. This could result in an underestimation of survival when applied to patients treated with current systemic therapies and supportive care. It is important for physicians to have an accurate method to predict survival in patients to ensure that appropriate treatments can be recommended.

Over 170,000 cases of metastatic brain tumors are diagnosed in the United States each year; and the length of survival for patients with brain metastases is often quite limited, ranging from a few weeks to several months.¹ The Radiation Therapy Oncology Group (RTOG) Recursive Partitioning Analysis (RPA) and the Graded Prognostic Assessment (GPA) are 2 prognostic indices that have been validated to predict survival and guide the treatment of these patients.^2-5 The RPA and GPA indices were formulated by comparing survival to patient and tumor characteristics compiled from RTOG brain metastasis treatment protocols spanning greater than 3 decades. The RPA has 3 classes of patients enumerated as “I”, “II”, and “III,” with class I patients having the longest predicted survival and class III patients having the worst prognosis. The RPA classes are based upon factors that include patient age and Karnofsky Performance Status (KPS) as well as control of the primary tumor and evidence of extra-cranial metastases (Table 1).² The GPA has 4 classes of patients with a score that may be considered analogous to a grade point average achieved by students in school. The classes are arranged into 4 groupings, which are divided from best to worst prognosis as follows: 3.5 to 4.0, 3.0, 1.5 to 2.5, and 0.0 to 1.0. The GPA employs criteria similar to but slightly different from those used in the RPA, estimating survival by patient age and performance status as well as the number of brain metastases and evidence of extracranial metastases (Table 2).⁴

Treatment options for patients with brain metastases include surgery, stereotactic radiosurgery (SRS), whole brain radiation therapy (WBRT), supportive measures such as corticosteroids, or a combination of these modalities. The survival of the worst prognosis brain metastases patients treated with WBRT and steroids is estimated by the RPA and GPA tools to be 2.3 months and 2.6 months, respectively.^2,4 As noted above, the patient data from which the RPA and GPA indices were created included patients treated on clinical trials. This could have resulted in the selection of patients more fit than average patients and lead to an overestimation of survival when applied to all patients. The clinical trial data used were drawn from over 3 decades, during which supportive care and chemotherapy treatments improved. This could result in an underestimation of survival when applied to patients treated with current systemic therapies and supportive care. It is important for physicians to have an accurate method to predict survival in patients to ensure that appropriate treatments can be recommended.

Over 170,000 cases of metastatic brain tumors are diagnosed in the United States each year; and the length of survival for patients with brain metastases is often quite limited, ranging from a few weeks to several months.¹ The Radiation Therapy Oncology Group (RTOG) Recursive Partitioning Analysis (RPA) and the Graded Prognostic Assessment (GPA) are 2 prognostic indices that have been validated to predict survival and guide the treatment of these patients.^2-5 The RPA and GPA indices were formulated by comparing survival to patient and tumor characteristics compiled from RTOG brain metastasis treatment protocols spanning greater than 3 decades. The RPA has 3 classes of patients enumerated as “I”, “II”, and “III,” with class I patients having the longest predicted survival and class III patients having the worst prognosis. The RPA classes are based upon factors that include patient age and Karnofsky Performance Status (KPS) as well as control of the primary tumor and evidence of extra-cranial metastases (Table 1).² The GPA has 4 classes of patients with a score that may be considered analogous to a grade point average achieved by students in school. The classes are arranged into 4 groupings, which are divided from best to worst prognosis as follows: 3.5 to 4.0, 3.0, 1.5 to 2.5, and 0.0 to 1.0. The GPA employs criteria similar to but slightly different from those used in the RPA, estimating survival by patient age and performance status as well as the number of brain metastases and evidence of extracranial metastases (Table 2).⁴

Treatment options for patients with brain metastases include surgery, stereotactic radiosurgery (SRS), whole brain radiation therapy (WBRT), supportive measures such as corticosteroids, or a combination of these modalities. The survival of the worst prognosis brain metastases patients treated with WBRT and steroids is estimated by the RPA and GPA tools to be 2.3 months and 2.6 months, respectively.^2,4 As noted above, the patient data from which the RPA and GPA indices were created included patients treated on clinical trials. This could have resulted in the selection of patients more fit than average patients and lead to an overestimation of survival when applied to all patients. The clinical trial data used were drawn from over 3 decades, during which supportive care and chemotherapy treatments improved. This could result in an underestimation of survival when applied to patients treated with current systemic therapies and supportive care. It is important for physicians to have an accurate method to predict survival in patients to ensure that appropriate treatments can be recommended.