A Surveillance, Epidemiology and End Results-Medicare data analysis of elderly patients with glioblastoma multiforme: Treatment patterns, outcomes and cost.

The Surveillance, Epidemiology and End Results (SEER) database was used to determine the treatment patterns, outcomes and cost of therapy in elderly patients with glioblastoma multiforme (GBM). The SEER-Medicare linked database was used to identify patients aged >66 years with GBM diagnosed between 1997 and 2009. The patients were stratified by initial treatment following diagnostic surgery (resection or biopsy) into 6 groups as follows: No treatment, standard radiation therapy (SRT) with and without concurrent temozolomide (TMZ), hypofractionated RT (HRT) with and without concurrent TMZ, or TMZ alone. The 3,759 patients identified had a median age of 74 years (range, 66-97 years). A total of ~48% of the patients received SRT without TMZ; ~10% received SRT with concurrent TMZ; ~29% received no treatment; ~10% received HRT without TMZ; ~1% received HRT with TMZ; and <1% received TMZ alone. Untreated patients had a median survival of 2 months (range, 0-89 months). Patients treated with SRT with and without concurrent TMZ had a median survival of 11 and 9 months, respectively (P=0.01). Patients treated with HRT with and without TMZ or TMZ alone had a median survivals of 3 months [adjusted hazard ratio (AHR)=0.48; 95% confidence interval (CI): 0.36-0.66], 4 months (AHR=0.55; 95% CI: 0.49-0.62) and 6 months (AHR=0.43; 95% CI: 0.29-0.62), respectively. The median post-surgery total treatment cost for patients receiving HRT with and without TMZ or TMZ alone was 63,915, 42,834 and 48,298 USD, respectively. Standard RT with concurrent TMZ was associated with improved survival, even in patients aged >75 years. HRT with and without concurrent TMZ and TMZ alone improved survival compared to the no treatment group. Therefore, in certain cases, HRT or TMZ alone may be more cost-effective, with similar survival outcomes. The various treatment options highlight the need for geriatric assessment tools to aid in therapeutic decision making.

Predicted risks of second malignant neoplasm incidence and mortality due to secondary neutrons in a girl and boy receiving proton craniospinal irradiation.

The purpose of this study was to compare the predicted risks of second malignant neoplasm (SMN) incidence and mortality from secondary neutrons for a 9-year-old girl and a 10-year-old boy who received proton craniospinal irradiation (CSI). SMN incidence and mortality from neutrons were predicted from equivalent doses to radiosensitive organs for cranial, spinal and intracranial boost fields. Therapeutic proton absorbed dose and equivalent dose from neutrons were calculated using Monte Carlo simulations. Risks of SMN incidence and mortality in most organs and tissues were predicted by applying risks models from the National Research Council of the National Academies to the equivalent dose from neutrons; for non-melanoma skin cancer, risk models from the International Commission on Radiological Protection were applied. The lifetime absolute risks of SMN incidence due to neutrons were 14.8% and 8.5%, for the girl and boy, respectively. The risks of a fatal SMN were 5.3% and 3.4% for the girl and boy, respectively. The girl had a greater risk for any SMN except colon and liver cancers, indicating that the girl's higher risks were not attributable solely to greater susceptibility to breast cancer. Lung cancer predominated the risk of SMN mortality for both patients. This study suggests that the risks of SMN incidence and mortality from neutrons may be greater for girls than for boys treated with proton CSI.

The risk of developing a second cancer after receiving craniospinal proton irradiation.

The purpose of this work was to compare the risk of developing a second cancer after craniospinal irradiation using photon versus proton radiotherapy by means of simulation studies designed to account for the effects of neutron exposures. Craniospinal irradiation of a male phantom was calculated for passively-scattered and scanned-beam proton treatment units. Organ doses were estimated from treatment plans; for the proton treatments, the amount of stray radiation was calculated separately using the Monte Carlo method. The organ doses were converted to risk of cancer incidence using a standard formalism developed for radiation protection purposes. The total lifetime risk of second cancer due exclusively to stray radiation was 1.5% for the passively scattered treatment versus 0.8% for the scanned proton beam treatment. Taking into account the therapeutic and stray radiation fields, the risk of second cancer from intensity-modulated radiation therapy and conventional radiotherapy photon treatments were 7 and 12 times higher than the risk associated with scanned-beam proton therapy, respectively, and 6 and 11 times higher than with passively scattered proton therapy, respectively. Simulations revealed that both passively scattered and scanned-beam proton therapies confer significantly lower risks of second cancers than 6 MV conventional and intensity-modulated photon therapies.