A. Gabriella Wernicke, Andrew W. Smith, Shoshana Taube, Menachem Z. Yondorf, Bhupesh Parashar, Samuel Trichter, Lucy Nedialkova, Albert Sabbas, Paul Christos, Rohan Ramakrishna, Susan C. Pannullo, Philip E. Stieg, and Theodore H. Schwartz
Managing patients whose intraparenchymal brain metastases recur after radiotherapy remains a challenge. Intraoperative cesium-131 (Cs-131) brachytherapy performed at the time of neurosurgical resection may represent an excellent salvage treatment option. The authors evaluated the outcomes of this novel treatment with permanent intraoperative Cs-131 brachytherapy.
Thirteen patients with 15 metastases to the brain that recurred after stereotactic radiosurgery and/or whole brain radiotherapy were treated between 2010 and 2015. Stranded Cs-131 seeds were placed as a permanent volume implant. Prescription dose was 80 Gy at 5-mm depth from the resection cavity surface. The primary end point was resection cavity freedom from progression (FFP). Resection cavity freedom from progression (FFP), regional FFP, distant FFP, median survival, overall survival (OS), and toxicity were assessed.
The median duration of follow-up after salvage treatment was 5 months (range 0.5–18 months). The patients' median age was 64 years (range 51–74 years). The median resected tumor diameter was 2.9 cm (range 1.0–5.6 cm). The median number of seeds implanted was 19 (range 10–40), with a median activity per seed of 2.25 U (range 1.98–3.01 U) and median total activity of 39.6 U (range 20.0–95.2 U). The 1-year actuarial local FFP was 83.3%. The median OS was 7 months, and 1-year OS was 24.7%. Complications included infection (3), pseudomeningocele (1), seizure (1), and asymptomatic radionecrosis (RN) (1).
After failure of prior irradiation of brain metastases, re-irradiation with intraoperative Cs-131 brachytherapy implants provides durable local control and limits the risk of RN. The authors' initial experience demonstrates that this treatment approach is well tolerated and safe for patients with previously irradiated tumors after failure of more than 1 radiotherapy regimen and that it results in excellent response rates and minimal toxicity.
A. Gabriella Wernicke, Menachem Z. Yondorf, Luke Peng, Samuel Trichter, Lucy Nedialkova, Albert Sabbas, Fridon Kulidzhanov, Bhupesh Parashar, Dattatreyudu Nori, K. S. Clifford Chao, Paul Christos, Ilhami Kovanlikaya, Susan Pannullo, John A. Boockvar, Philip E. Stieg, and Theodore H. Schwartz
Resected brain metastases have a high rate of local recurrence without adjuvant therapy. Adjuvant whole-brain radiotherapy (WBRT) remains the standard of care with a local control rate > 90%. However, WBRT is delivered over 10–15 days, which can delay other therapy and is associated with acute and long-term toxicities. Permanent cesium-131 (131Cs) implants can be used at the time of metastatic resection, thereby avoiding the need for any additional therapy. The authors evaluated the safety, feasibility, and efficacy of a novel therapeutic approach with permanent 131Cs brachytherapy at the resection for brain metastases.
After institutional review board approval was obtained, 24 patients with a newly diagnosed metastasis to the brain were accrued to a prospective protocol between 2010 and 2012. There were 10 frontal, 7 parietal, 4 cerebellar, 2 occipital, and 1 temporal metastases. Histology included lung cancer (16), breast cancer (2), kidney cancer (2), melanoma (2), colon cancer (1), and cervical cancer (1). Stranded 131Cs seeds were placed as permanent volume implants. The prescription dose was 80 Gy at a 5-mm depth from the resection cavity surface. Distant metastases were treated with stereotactic radiosurgery (SRS) or WBRT, depending on the number of lesions. The primary end point was local (resection cavity) freedom from progression (FFP). Secondary end points included regional FFP, distant FFP, median survival, overall survival (OS), and toxicity.
The median follow-up was 19.3 months (range 12.89–29.57 months). The median age was 65 years (range 45–84 years). The median size of resected tumor was 2.7 cm (range 1.5–5.5 cm), and the median volume of resected tumor was 10.31 cm3 (range 1.77–87.11 cm3). The median number of seeds used was 12 (range 4–35), with a median activity of 3.82 mCi per seed (range 3.31–4.83 mCi) and total activity of 46.91 mCi (range 15.31–130.70 mCi). Local FFP was 100%. There was 1 adjacent leptomeningeal recurrence, resulting in a 1-year regional FFP of 93.8% (95% CI 63.2%–99.1%). One-year distant FFP was 48.4% (95% CI 26.3%–67.4%). Median OS was 9.9 months (95% CI 4.8 months, upper limit not estimated) and 1-year OS was 50.0% (95% CI 29.1%–67.8%). Complications included CSF leak (1), seizure (1), and infection (1). There was no radiation necrosis.
The use of postresection permanent 131Cs brachytherapy implants resulted in no local recurrences and no radiation necrosis. This treatment was safe, well tolerated, and convenient for patients, resulting in a short radiation treatment course, high response rate, and minimal toxicity. These findings merit further study with a multicenter trial.