TARGIT-R (Retrospective): North American Experience with Intraoperative Radiation Using Low-Kilovoltage X-Rays for Breast Cancer.

BACKGROUND: Single-dose intraoperative radiotherapy (IORT) is an emerging treatment for women with early stage breast cancer. The objective of this study was to define the frequency of IORT use, patient selection, and outcomes of patients treated in North America. METHODS: A multi-institutional retrospective registry was created, and 19 institutions using low-kilovoltage IORT for the treatment of breast cancer entered data on patients treated at their institution before July 31, 2013. Patient selection, IORT treatment details, complications, and recurrences were analyzed. RESULTS: From 2007 to July 31, 2013, a total of 935 women were identified and treated with lumpectomy and IORT. A total of 822 patients had at least 6 months' follow-up documented and were included in the analysis. The number of IORT cases performed increased significantly over time (p < 0.001). The median patient age was 66.8 years. Most patients had disease that was <2 cm in size (90 %) and was estrogen positive (91 %); most patients had invasive ductal cancer (68 %). Of those who had a sentinel lymph node procedure performed, 89 % had negative sentinel lymph nodes. The types of IORT performed were primary IORT in 79 %, secondary IORT in 7 %, or planned boost in 14 %. Complications were low. At a median follow-up of 23.3 months, crude in-breast recurrence was 2.3 % for all patients treated. CONCLUSIONS: IORT use for the treatment of breast cancer is significantly increasing in North America, and physicians are selecting low-risk patients for this treatment option. Low complication and local recurrence rates support IORT as a treatment option for selected women with early stage breast cancer.

Treatment of pediatric intracranial arteriovenous malformations with linear-accelerator-based stereotactic radiosurgery: the University of Pennsylvania experience.

There are relatively few reports detailing the outcome of children and adolescents with arteriovenous malformations (AVMs) treated with stereotactic radiosurgery (SRS). We reviewed our experience over the past decade to determine whether the outcomes and toxicity were similar to those reported in adults. Seventeen patients 18 years of age or younger underwent linear-accelerator-based SRS. The targeted volume was greater than 3 cm(3) in 65% of cases (range 0.7-25 cm(3); median volume 6.9 cm(3)). The prescribed radiation doses varied from 16 to 18 Gy, with 70% receiving the highest dose. Using only angiographic data, the obliteration rate was 80% (8 of 10 patients), but using both MRA/MRI and angiographic data, it was 53% (9 of 17 patients). Four patients developed late effects potentially attributable to the radiation between 2 months and 3 years following SRS. One of these was transient and disappeared completely within a few days, but in the other 3 patients, the neurologic sequelae were permanent. Two of the 4 complications appeared to be due to radiation necrosis/edema, whereas the remaining 2 may have been due to vasculopathy. All 4 patients with complications had treatment volumes greater than 5 cm(3) (5.4, 6.9, 11.1, 16.4 cm(3)), all had a prescribed dose of 18 Gy and all had initially presented with an AVM hemorrhage. Linear-accelerator-based SRS is effective in obliterating most AVMs in children; however, the potential for late effects exists, especially for those patients with larger target volumes.