CYBERKNIFE IN TREATMENT OF PITUITARY ADENOMAS

CYBERKNIFE IN TREATMENT OF PITUITARY ADENOMAS


In recent years, CyberKnife has emerged as an important treatment modality in the management of pituitary adenomas. Treatment results after performing CyberKnife and the complications of this procedure are reviewed.
Methods
Twenty-six patients with pituitary adenomas received stereotactic radiosurgery with the CyberKnife (CKRS). The follow-up periods ranged from 7 months to 47 months (mean±SD : 30±12.7 months). The patients consisted of 17 with non-functioning adenomas, 3 with prolactinomas and 6 with acromegaly. The change in the tumor volume, visual acuity, hormonal function, and complications by this therapy were analyzed in each case.
Results
The tumor control rate was 92.3%. Hormonal function was improved in all of the 9 (100%) functioning adenomas. Hormonal normalization was observed in 4 of the 9 (44%) patients with a mean duration of 16 months. In two patients (7.6%), visual acuity worsened due to cystic enlargement of the tumor after CKRS. No other complications were observed.
Conclusion
CyberKnife is considered safe and effective in selected patients with pituitary adenomas. However, longer follow-up is required for a more complete assessment of late toxicity and treatment efficacy.

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Radiosurgical Treatment of Primary Liver Cancer: Baylor Radiosurgery Center Experience

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 liver transplant 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

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PROGRESS IN RADIATION ONCOLOGY

PROGRESS IN RADIATION ONCOLOGY

Dr. Janos Stumpf - ADVISOR ONCOLOGY – CYBERKNIFE SERVICES

End of the month November, was an academic feast for the Indian Radiation Oncologists at Hyderabad.

The content of the conference can be summarized in three words: It was about Research, Discipline and Development, especially that of the new machines. It is our pride to realize and say that even latest knowledge about the technical progress has found its way to India, no matter how expensive the machines are. “Precision in Delivery of Radiation” is the mantra for all these technical aspects. Tomotherapy, Cyberknife and Rapid Arc are all the ways to do radio therapy on an extremely precise way.

Cyberknife was covered by two speakers. An eminent guest from California Dr.Nissar Syed was kind enough to give an over-all review about the machine. His talk was followed by the ‘Indian experience’ with Cyberknife based on more than hundred fifty cases treated already at ASH Chennai. Characteristics of the first 150 cases were presented. Apollo has considerable success:- partial remission even in majority of the ‘lost’ cases.

Beside the advantage of saving normal tissue in the brain or extracranially, CK represents a huge leap forward in treating moving targets like cancer in the lung, liver or in the prostate. All these three organs, move during the radiotherapy.



The first patient, Master Shanka had very serious neurological complaints at the time when he came to Apollo. He was attended by Sr. Consultant Neurosurgeon Dr.Balamurugan. However his attempt to remove the haemangioblastoma from the patient’s brainstem was confined to fail due to the dangerously high vascularity which is the nature of that kind of tumors. But this surgical nightmare can be converted into an advantage with the help of High Precision Irradiation (HPI). High vascularity means high density of endothelial cells which are covering the inner surface of the vessels. These vulnerable cells can react with an overgrowth for the exposure of radiation.


Few months after the success full Stereotactic Radiosurgery with CK, part of the tumor has been obliterated its overall size started to come down.This is why the patient has improved and could resume his normal life.

Fate of a patient with inoperable lung cancer is practically known at the time of the diagnosis. Only a very minimal percentage of the inoperable lung cancer cases can be saved by the combination of conventional irradiation with chemotherapy. CK seems to bring a new hope for these patients. A 57 year old gentleman from the neighboring Srilanka successfully conquered one cancer 10 years ago with the help of Apollo Speciality Hospital. He came with hope again when an inoperable lung cancer in his chest was diagnosed. Chemotherapy has failed unfortunately. And then Cyberknife seemed to come for his rescue. High precision and short duration, biologically very intensive radiation has resulted in an impressive remission of his advanced lung cancer without any side effects. This aggressive cancer does have the capacity of invading the rest of the body. As a matter of fact the same has been observed with that particular patient too. But for him this is not the “end of the road”. A second CK treatment is planned to attend all the new sites of cancers shown on the PET CT. Highly sophisticated tools in radiation oncology do allow us to provide longer control with reasonable if not excellent quality of life even in an aggressive cancer.

There is a beautiful sentence told by Rabindranath Tagore about the disease in general. “DEATH DOES NOT HURT US, BUT DISEASE DOES, BECAUSE DISEASE CONSTANTLY REMINDS US OF HEALTH AND YET WITHOLDS IT FROM US.”

This is double true for cancer. Quality of life of a patient has to be one of the primary concerns of an oncologists. Many cancers have a tendency to migrate to the bone, to the spine. These metastatic lesions have the capacity to paralyze the patients by compressing the spinal cord. Chemotherapy frequently has only temporary control over the progress and so does conventional radiotherapy. But high precision in CK helps. We have the technical skill and opportunity to give high precision irradiation to the spine and to arrest this type of tumours even before they cause the extremely bad condition of transverse lesion of the spine. A Professor from George-Towns University in Washington DC said “by now we hardly deal with paralysis due to metastasis to the spine. It is being attended with CK at a curable and controllable stage and the patient will not be confined to bed for the rest of his/her life.


The basic question: ‘How cancer can be tamed in general’ still remains unanswered. But the tremendous progress gives hope for both temporary control with good quality of life and for cure in many cases. It is our job and duty to know about new developments and to apply them with wisdom. This conference was all about this.