Patients with metastatic
renal cell carcinoma (RCC) to the brain have a very poor prognosis of three
months if left untreated. SRS is an effective treatment modality in numerous
patients. This case exemplifies the utility of stereotactic radiosurgery (SRS)
in prolonging survival and maintaining quality of life in a patient with RCC.
This 64-year-old female patient initially presented to her primary care
physician 22 months after a left nephrectomy for RCC with complaints of mild,
intermittent headaches and difficulty with balance. An MRI revealed five
cerebellar lesions suspicious for intracranial metastasis. The patient's first
GKRS treatment targeted four lesions with 22 Gy at the 50% isodose line. She
underwent a total of seven GKRS treatments over the next 60 months for
recurrent metastases to the brain. 72 months and 12 months have now passed since
her brain metastases were first discovered and since her last GKRS treatment,
respectively, and this woman is alive with considerable quality of life and no
evidence of metastatic reoccurrence. This case shows that repeated GKRS
treatments, with minimal surgical intervention, can effectively treat multiple
intracranial lesions in select patients, prolonging survival and avoiding
iatrogenic neurocognitive decline while maintaining a high quality of life. To know more about cyberknife kindly blog your comments or you can write to me at lakshmipriya_b@apollohospitals.com or call 9940675877
Radiosurgical Treatment of Primary Liver Cancer: Baylor Radiosurgery Center Experience
John O’Connor, M.D., Medical DirectorBaylor Radiosurgery Center, Dallas, TXRobert Goldstein, M.D., Director, Liver and Pancreas Disease CenterBaylor University Medical Center, Dallas, TX
Hepatocellular carcinoma (HCC) is the fifth most common cancer and third leading cause of cancer death, with 626,000 new cases and 598,000 deaths per year.1 Although it is less common in the United States, its incidence has tripled in the past 30 years principally in relation to the spread of hepatitis C infection.2 Survival for patients with hepatocellular cancer remains poor, about 10% at 5 years.3 HCC is potentially curable with hepatic resection or transplantation, but fewer than 30% of patients are eligible for surgery.4,5 Liver transplantation is the primary treatment for patients with cirrhosis and unresectable HCC, with low rates of recurrence and 5-year survival of about 70%.6,7
Stereotactic body radiotherapy (SBRT) has the ability to deliver high, focused doses while limiting irradiation of normal liver tissue. The use of SBRT for both primary and metastatic liver cancer is increasing worldwide at an impressive rate as clinicians are encouraged by favorable safety and efficacy data.8-11 CyberKnife® researchers have been active in the use of SBRT for liver as well.12-14 At the Baylor Radiosurgery Center we have been treating unresectable HCC since April of 2005. In March 2010 we updated our findings at the CyberKnife Scientific Meeting in Dallas.
We presented outcomes of a retrospective review of 24 patients with 27 tumors. All patients were evaluated by a livertransplant surgeon prior to radiosurgery and were deemed unresectable. The median tumor diameter was 4 cm and we have successfully treated liver tumors as large as 11 cm in diameter. Patients were treated with the CyberKnife System using Synchrony® Respiratory Tracking. The median dose was 42 Gy (range 27 - 54 Gy) to the median 66% isodose line (range 50 - 80%), delivered in 3 daily fractions in 22 patients and 5 fractions in four patients. We followed our patients using MRI obtained at 3-month intervals.
To date our outcomes have been encouraging. Grade 1 or 2 toxicity (based on CTCAE 3.0 guidelines) occurred in four patients (17%); a single Grade 3 toxicity was observed. There were no Grade 4-5 toxicities and no occurrence of radiation-induced liver disease. Overall local tumor control in all patients based on RECIST criteria was 87% at a median follow-up of 12 months. One-year Kaplan-Meier survival was 43%, and median survival was 11 months.
An additional eight patients with HCC (and nine tumors) were treated as a “bridge” to liver transplantation, that is, to control the growth of their tumors so that they may remain on the organ waitlist until a liver is available for transplant. We presented our preliminary findings on these patients at the 2009 meeting of the American Society for Radiation Oncology (ASTRO).15 All of these patients proceeded to transplant in a median of 90 days (range 8 – 209 days) after radiosurgery. We assessed the tissue response in the explanted tissue; three of the lesions responded completely, three were reduced in size, and three were stable.
The CyberKnife System has become a valuable component of our treatment program for unresectable HCC. Its ability to track liver tumors as they move with respiration has allowed us to deliver high doses of radiation accurately to achieve excellent rates of local control.
Source: Accuray Newsletter April 2010
For more information you may please blog your comments or write to lakshmipriya_b@apollohospitals.com
Stereotactic body radiation therapy for liver metastases
O Dawood, A Mahadevan, K Goodman ,European J Cancer 2009;45:2947-2959.
This review focuses on stereotactic body radiation therapy (SBRT) as an alternative, non-invasive approach to the treatment of liver metastases. Treatment considerations of SBRT for liver metastases are presented with particular emphasis on the challenges of organ motion and the low tolerance of the surrounding hepatic parenchyma. Multiple approaches to tumor motion are discussed, including tumor tracking versus motion-compensation techniques. Issues of patient eligibility criteria, patient set-up, target definition, treatment dosimetry and fractionation are also discussed. Clinical results to date from 15 published reports, including a summary of the latest in-press results from Stanford using the CyberKnife System, are presented. These clinical reports demonstrate the safety and efficacy of SBRT for liver metastasis with 18-month and 2-year local control rates ranging from 71-93% and 71-86%, respectively.
The review concludes by stressing the importance of addressing hepatic tumor motion to ensure the dose reaches the tumor and spares the surrounding normal tissue. The authors suggest more rigorous phase II clinical studies are necessary to establish the long-term durability of efficacy and toxicity results.
Stereotactic body radiotherapy for isolated para-aortic lymph node recurrence after curative resection in gastric cancer
Metastases from gastric cancer are common and can progress rapidly; even with aggressive treatment 5-year survival rates are low. However, researchers from Korea Institute of Radiological & Medical Sciences hypothesized that there is a certain population of such patients in whom the disease follows a more indolent course, based on studies of patients with
resected liver metastases. This population may benefit from SRS of isolated metastases from
gastric primaries. Thus, they treated 7 such patients with the CyberKnife® System, delivering 45 to 51 Gy (median 48 Gy) in 3 fractions. The patients were followed for 14 to 33 months (median 26 months). Local control was achieved in 6 of 7 patients; 2 patients were disease-free, 3 were alive with disease, and 2 patients died of disease progression. Three-year actuarial overall survival was 43%, and disease-free survival was 29%. The authors conclude that the results support their hypothesis that an indolent subgroup with less aggressive disease progression who could benefit
from the use of local treatments such as CyberKnife Radiosurgery.
