When used to treat pediatric patients with intracranial malignant tumors, proton therapy may limit the toxicity of radiation therapy while preserving tumor control, according to research presented today at the American Society for Radiation Oncology's (ASTRO's) 55th Annual Meeting.
Typically, central nervous system malignancies are treated with surgical resection and post-operative radiation therapy. Proton therapy, an external beam radiation therapy in which protons deliver precise radiation doses to a tumor, offers significant sparing of healthy tissues outside the target region, compared to conventional photon radiotherapy. Proton therapy is frequently used to treat central nervous system malignancies in young children in order to minimize the amount of radiation exposure to their still-developing brain. Although this therapy holds great promise, to date, published clinical data are limited.
This study evaluated the largest reported group of pediatric patients treated with proton therapy-70 patients with localized ependymoma, a relatively common childhood tumor. The patients in the study ranged in age from one to 20 years and were all treated with involved-field proton radiation at the Massachusetts General Hospital in Boston from October 2000 to February 2011. Forty-six of the patients (66 percent) had a gross total resection, meaning that the tumor was completely removed; and 24 patients (34 percent) had a subtotal resection, meaning that only a portion of the tumor was removed.
Upon patient follow-up at 46 months after proton therapy treatment, the three-year local control was 83 percent; progression free survival (PFS) was 76 percent; and overall survival (OS) was 95 percent. The researchers found that subtotal resection surgery correlated with decreased PFS (54 percent) and OS (90 percent), compared to the patients who underwent complete tumor removal prior to proton therapy, who had a PFS of 88 percent and an OS of 97 percent.
In addition to survival outcomes, cognitive and endocrine outcomes were analyzed. Neuropsychological assessments were administered before and after proton therapy to measure total intelligence quotient (IQ). Scales of Independent Behavior (SIB-R), a written questionnaire that assessed functional independence, were completed by the patients' parents. Within a subset of 14 of the patients, the average IQ was 108.5 at baseline, and 111.3 after two years of follow-up. In a larger group of 28 of the patients, overall SIB-R score was 100.1 at baseline, and 100.8 after two years of follow-up. It was also noted that few patients developed evidence of growth hormone deficiency (GHD), hypothyroidism or hearing loss.
"This study represents the best available evidence on the use of proton radiotherapy in the pediatric population," said Shannon MacDonald, the principal investigator of the study, a pediatric radiation oncologist at the Massachusetts General Hospital. "Our analysis is the first to present auditory, endocrine and cognitive outcomes, the domains expected to benefit from this highly streamlined form of radiation therapy. Given the increasing numbers of proton facilities and the high cost of proton treatment, this data was urgently needed to provide evidence-based guidance on proton therapy outcomes for pediatric brain tumor patients."
Explore further: Proton therapy offers new, precise cancer treatment for children with high-risk neuroblastoma
More information: The abstract, "Proton Radiation Therapy for Pediatric Central Nervous System Ependymoma: Clinical Outcomes for 70 patients," will be presented in detail at ASTRO's 55th Annual Meeting.
Medical Xpress on facebook
Related Stories
Proton therapy offers new, precise cancer treatment for children with high-risk neuroblastoma
Aug 13, 2013
Proton therapy, using high-energy subatomic particles, may offer a precise, organ-sparing treatment option for children with high-risk forms of neuroblastoma. For patients in a new study of advanced radiation ...
Proton imaging provides more accuracy, less radiation to pediatric cancer patients
Apr 29, 2011
Proton radiography imaging used prior to and during proton treatments for pediatric cancer patients provides for more accurate treatment delivery and a lower dose of radiation compared to standard diagnostic X-rays and cone ...
Proton therapy lowers chance of later cancers
Sep 22, 2008
Patients who are treated with proton therapy (a specialized type of external beam radiation therapy using protons rather than X-rays to treat cancer) decreases the risk of patients developing a secondary cancer by two-fold, ...
Proton beam therapy shows encouraging long-term outcome for patients with locally advanced sinonasal cancers
Feb 25, 2010
Proton beam radiation therapy shows encouraging results for patients with locally advanced sinonasal malignancies, according to a study presented at the Multidisciplinary Head and Neck Cancer Symposium.
Carbon ion radiotherapy safe and effective for treating inoperable spinal tumors
Aug 12, 2013
A new analysis has found that a type of radiation therapy called carbon ion radiotherapy can control cancer growth and prolong survival in patients with spinal tumors. Published early online in Cancer, a peer-reviewed journa ...
Recommended for you
Sulfasalazine does not reduce diarrhea for patients receiving pelvic radiation therapy
19 seconds ago
Patients receiving radiotherapy (RT) for cancers in the pelvic region can experience diarrhea, a negative side effect of radiation treatment. Sulfasalazine, an oral tablet used to treat inflammation of the bowels, had been ...
Researchers identify proteins that may help brain tumors spread
28 minutes ago
Scientists at the University of Alabama at Birmingham have identified a molecular pathway that seems to contribute to the ability of malignant glioma cells in a brain tumor to spread and invade previously ...
Simple, two-question survery accurately screens cancer patients for depression
48 minutes ago
Cancer patients can be accurately screened for major depression with a simple two-question survey, according to a study presented Sept. 23 at the American Society for Radiation Oncology's 55th Annual Meeting.
Research to change how breast cancer treated
1 hour ago
(Medical Xpress)—Research from the newly formed Cambridge Cancer Centre, a collaboration between the University of Cambridge, Cambridge University Hospitals NHS Foundation Trust, Cancer Research UK and ...
Functional disability high among newly diagnosed older breast cancer patients
9 hours ago
Many older women with newly diagnosed breast cancer have difficulty accomplishing daily tasks, and African-Americans seem to be disproportionately affected. Those are the findings of a new study published early online in ...
Eating, exercises improve diet after pharyngeal cancer Tx
Sep 20, 2013
(HealthDay)—Patients who maintain eating and a regimen of swallowing exercises during treatment for pharyngeal cancers have the highest rate of return to a regular diet following treatment, according to ...
User comments
© Medical Xpress 2011-2013, Phys.org network
When used to treat pediatric patients with intracranial malignant tumors, proton therapy may limit the toxicity of radiation therapy while preserving tumor control, according to research presented today at the American Society for Radiation Oncology's (ASTRO's) 55th Annual Meeting.
Typically, central nervous system malignancies are treated with surgical resection and post-operative radiation therapy. Proton therapy, an external beam radiation therapy in which protons deliver precise radiation doses to a tumor, offers significant sparing of healthy tissues outside the target region, compared to conventional photon radiotherapy. Proton therapy is frequently used to treat central nervous system malignancies in young children in order to minimize the amount of radiation exposure to their still-developing brain. Although this therapy holds great promise, to date, published clinical data are limited.
This study evaluated the largest reported group of pediatric patients treated with proton therapy-70 patients with localized ependymoma, a relatively common childhood tumor. The patients in the study ranged in age from one to 20 years and were all treated with involved-field proton radiation at the Massachusetts General Hospital in Boston from October 2000 to February 2011. Forty-six of the patients (66 percent) had a gross total resection, meaning that the tumor was completely removed; and 24 patients (34 percent) had a subtotal resection, meaning that only a portion of the tumor was removed.
Upon patient follow-up at 46 months after proton therapy treatment, the three-year local control was 83 percent; progression free survival (PFS) was 76 percent; and overall survival (OS) was 95 percent. The researchers found that subtotal resection surgery correlated with decreased PFS (54 percent) and OS (90 percent), compared to the patients who underwent complete tumor removal prior to proton therapy, who had a PFS of 88 percent and an OS of 97 percent.
In addition to survival outcomes, cognitive and endocrine outcomes were analyzed. Neuropsychological assessments were administered before and after proton therapy to measure total intelligence quotient (IQ). Scales of Independent Behavior (SIB-R), a written questionnaire that assessed functional independence, were completed by the patients' parents. Within a subset of 14 of the patients, the average IQ was 108.5 at baseline, and 111.3 after two years of follow-up. In a larger group of 28 of the patients, overall SIB-R score was 100.1 at baseline, and 100.8 after two years of follow-up. It was also noted that few patients developed evidence of growth hormone deficiency (GHD), hypothyroidism or hearing loss.
"This study represents the best available evidence on the use of proton radiotherapy in the pediatric population," said Shannon MacDonald, the principal investigator of the study, a pediatric radiation oncologist at the Massachusetts General Hospital. "Our analysis is the first to present auditory, endocrine and cognitive outcomes, the domains expected to benefit from this highly streamlined form of radiation therapy. Given the increasing numbers of proton facilities and the high cost of proton treatment, this data was urgently needed to provide evidence-based guidance on proton therapy outcomes for pediatric brain tumor patients."
Explore further: Proton therapy offers new, precise cancer treatment for children with high-risk neuroblastoma
More information: The abstract, "Proton Radiation Therapy for Pediatric Central Nervous System Ependymoma: Clinical Outcomes for 70 patients," will be presented in detail at ASTRO's 55th Annual Meeting.
Medical Xpress on facebook
Related Stories
Proton therapy offers new, precise cancer treatment for children with high-risk neuroblastoma
Aug 13, 2013
Proton therapy, using high-energy subatomic particles, may offer a precise, organ-sparing treatment option for children with high-risk forms of neuroblastoma. For patients in a new study of advanced radiation ...
Proton imaging provides more accuracy, less radiation to pediatric cancer patients
Apr 29, 2011
Proton radiography imaging used prior to and during proton treatments for pediatric cancer patients provides for more accurate treatment delivery and a lower dose of radiation compared to standard diagnostic X-rays and cone ...
Proton therapy lowers chance of later cancers
Sep 22, 2008
Patients who are treated with proton therapy (a specialized type of external beam radiation therapy using protons rather than X-rays to treat cancer) decreases the risk of patients developing a secondary cancer by two-fold, ...
Proton beam therapy shows encouraging long-term outcome for patients with locally advanced sinonasal cancers
Feb 25, 2010
Proton beam radiation therapy shows encouraging results for patients with locally advanced sinonasal malignancies, according to a study presented at the Multidisciplinary Head and Neck Cancer Symposium.
Carbon ion radiotherapy safe and effective for treating inoperable spinal tumors
Aug 12, 2013
A new analysis has found that a type of radiation therapy called carbon ion radiotherapy can control cancer growth and prolong survival in patients with spinal tumors. Published early online in Cancer, a peer-reviewed journa ...
Recommended for you
Sulfasalazine does not reduce diarrhea for patients receiving pelvic radiation therapy
19 seconds ago
Patients receiving radiotherapy (RT) for cancers in the pelvic region can experience diarrhea, a negative side effect of radiation treatment. Sulfasalazine, an oral tablet used to treat inflammation of the bowels, had been ...
Researchers identify proteins that may help brain tumors spread
28 minutes ago
Scientists at the University of Alabama at Birmingham have identified a molecular pathway that seems to contribute to the ability of malignant glioma cells in a brain tumor to spread and invade previously ...
Simple, two-question survery accurately screens cancer patients for depression
48 minutes ago
Cancer patients can be accurately screened for major depression with a simple two-question survey, according to a study presented Sept. 23 at the American Society for Radiation Oncology's 55th Annual Meeting.
Research to change how breast cancer treated
1 hour ago
(Medical Xpress)—Research from the newly formed Cambridge Cancer Centre, a collaboration between the University of Cambridge, Cambridge University Hospitals NHS Foundation Trust, Cancer Research UK and ...
Functional disability high among newly diagnosed older breast cancer patients
9 hours ago
Many older women with newly diagnosed breast cancer have difficulty accomplishing daily tasks, and African-Americans seem to be disproportionately affected. Those are the findings of a new study published early online in ...
Eating, exercises improve diet after pharyngeal cancer Tx
Sep 20, 2013
(HealthDay)—Patients who maintain eating and a regimen of swallowing exercises during treatment for pharyngeal cancers have the highest rate of return to a regular diet following treatment, according to ...
User comments
© Medical Xpress 2011-2013, Phys.org network
0 comments:
Post a Comment