Leksell Radiosurgery for the 3 H Tumors: Hemangiomas, Hemangioblastomas, and Hemangiopericytomas.

Leksell stereotactic radiosurgery has proven to be effective for less common tumors encountered in the brain, including hemangiomas of the orbit or cavernous sinus, recurrent hemangiopericytomas, and both sporadic hemangioblastomas as well as those encountered in the context of von Hippel-Lindau (VHL) disease. While all three tumors are responsive to single-session radiosurgery, hemangiomas and hemangiopericytomas are the most likely to demonstrate tumor regression. Hemangiopericytomas that recur after initial resection can be lower grade or anaplastic and have both higher local as well as distant recurrence risks. Sporadic hemangioblastomas undergo Leksell radiosurgery at the time of recurrence after initial surgery. In the context of VHL, growing or recurrent tumors are treated with tumor control rates exceeding 90%. Tumor control improves with higher dose delivery, typically >15 Gy at the margin. Dose-limiting structures may include the optic apparatus for hemangiomas and brain stem locations for hemangioblastomas.

Hyperbaric oxygen treatment for post-radiation central nervous system injury: a retrospective case series.

Increased use of radiation therapy and increasing life spans following radiation treatment has led to an increase in the finding of post-radiation central nervous system injury in patients who have previously undergone radiation treatments. At this time, information regarding treatment for patients suffering from this serious side effect is limited and not readily available. It is imperative to examine possible treatment options, complications and success rates for these patients. This retrospective review will look at 10 patients who underwent hyperbaric oxygen therapy for post-radiation injury to the central nervous system. Review and investigation of the subjective, clinical and radiologic outcomes of these patients was conducted. It was determined that for patients with post-radiation central nervous system injury it is important to distinguish the exact diagnosis for each patient. For those patients with radiation necrosis, conclusion was made that hyperbaric oxygen (HBO2) therapy does lead to improvement in subjective, clinical and radiologic outcomes. However, the results were not consistent across all patients. For those patients with non-specific delayed radiation injury, findings showed that HBO2 does not lead to any improvement. Therefore, we conclude that for those patients who have been diagnosed with radiation necrosis of the central nervous system, we recommend HBO2 therapy as a potential treatment option for some patients.

Infratentorial craniospinal irradiation for von Hippel-Lindau: a retrospective study supporting a new treatment for patients with CNS hemangioblastomas.

Patients with von Hippel-Lindau (VHL) syndrome with diffuse CNS hemangioblastomas have morbidity related to their disease and require a lifetime of surgical resections. Ninety-seven percent of tumors progress, and 5-year surgery rates are 20%-60%. Stereotactic radiosurgery and fractionated radiotherapy have had limited success. For the first time, we have used infratentorial craniospinal radiation therapy (ICSRT) for VHL patients with CNS hemangioblastomas. Consecutive VHL patients treated at the National Institutes of Health with radiographic evidence of hemangioblastomas were included if they received ICSRT. Patients underwent neurologic examinations and imaging at 3- to 12-month intervals. Seven patients with 84 hemangioblastomas met eligibility criteria. ICSRT was commonly administered to 43.2 Gy in 24 fractions. Mean pre-ICSRT tumor volume was 5.48 cm(3). At a mean follow-up of 73.8 months, mean post-ICSRT tumor volume was 6.87 cm(3), and 91 tumors were identified. Complete radiographic resolution was achieved in 17.9% of lesions. Although many patients were no longer optimal surgical candidates, only 4 surgeries were needed for symptomatic lesions after ICSRT, compared with 33 prior. Acute toxicity was mild and no patient developed grade ≥1 late spinal cord toxicity according to the criteria of the Radiation Therapy Oncology Group/European Organisation for Research and Treatment of Cancer, despite the high dose that the entire spinal cord received. Clinical and radiographic stability or resolution was demonstrated in the majority of tumors. Tumor growth rate in this study was less than reported in natural history studies, and the rate of surgical intervention was reduced. ICSRT was well tolerated, can decrease hemangioblastoma growth rate, and is a potential therapeutic option for VHL patients that warrants further investigation.

Malignant glioma arising at the site of an excised cerebellar hemangioblastoma after irradiation in a von Hippel-Lindau disease patient.

We describe herein a malignant glioma arising at the site of the resected hemangioblastoma after irradiation in a patient with von Hippel-Lindau disease (VHL). The patient was a 25 year-old male with multiple hemangioblastomas at the cerebellum and spinal cord, multiple pancreatic cysts and a renal cell carcinoma; he was diagnosed as having VHL disease. The largest hemangioblastoma at the right cerebellar hemisphere was completely removed, and he received high-dose irradiation postoperatively. The tumor recurred at the same site 7 years later, which was a malignant glioma with no evidence of hemangioblastoma. The malignant glioma showed molecular genetic profiles of radiation-induced tumors because of its diffuse p53 immunostaining and the loss of p16 immunoreactivity. The genetic study to find the loss of heterozygosity (LOH) of VHL gene revealed that only the cerebellar hemangioblastoma showed allelic losses for the gene. To the best of our knowledge, this report is the first to show a malignant glioma that developed in a patient with VHL disease after radiation therapy at the site of an excised hemangioblastoma. This report also suggests that radiation therapy should be performed very carefully in VHL patients with hemangioblastomas.

Malignant transformation and new primary tumours after therapeutic radiation for benign disease: substantial risks in certain tumour prone syndromes.

In recent years the use of radiation treatment for benign tumours has increased with the advent of stereotactic delivery and, in particular, single high dose gamma knife therapy. This has been particularly true for benign CNS (central nervous system) tumours such as vestibular schwannoma, meningioma, pituitary adenoma, and haemangioblastoma. While short term follow up in patients with isolated tumours suggests this treatment is safe, there are particular concerns regarding its use in childhood and in tumour predisposing syndromes. We have reviewed the use of radiation treatment in these contexts with particular regard to malignant transformation and new tumour induction. This review indicates that much more caution is warranted regarding the use of radiation treatment for benign tumours in childhood and in tumour prone conditions such as the neurofibromatoses.

[External electron irradiation in 2 cases of capillary hemangioma of the optic disk]. / Irradiation externe par électrons de deux cas d'hémangiome capillaire de la papille.

The authors report on two cases of solitary capillary hemangioma of the optic disc, treated with external electron beam. The radiotherapist must know these rare indications of radiotherapy; and though it is a benign tumor, fractionated irradiation with low doses is excellent and generally safe.

[Capillary hemangioma of the retina. Laser scanning tomography follow-up after radiotherapy]. / Kapilläres Hämangiom der Netzhaut. Laser-Scanning-tomographische Verlaufsbeobachtungen nach Strahlentherapie.

We present a patient with isolated angiomatosis retinae, in whom ruthenium irradiation was administered for treatment of a secondary serous retinal detachment. Prior to therapy, we measured an increased vessel diameter. Following treatment, decreasing venous vessel diameter was documented three-dimensionally utilizing laser scanning tomography. The changes in vessel height (87%) exceeded the changes in width (49%). This is most probably because the vessels are embedded in the nerve fiber layer, stabilized by the surrounding tissues more in a horizontal than in a vertical direction. In addition, spontaneous venous pulsation located in the optic disc and in the retina was documented.

Hemodynamic changes after ruthenium irradiation of Hippel's angiomatosis.

The authors report a case of Hippel's angiomatosis successfully treated with contact beta irradiation. The area of the multiplex retinal angioma and the accompanying retinal detachment was irradiated with a 106Ru/106Rh radioactive applicator. Hemodynamic changes due to irradiation were followed up in the ipsilateral ophthalmic artery with transcranial Doppler sonography. Scarring was also demonstrated by fluorescein angiography and A- and B-scan ultrasonography. Irradiation caused the narrowing and later the occlusion of the precapillaries and capillaries (i.e. the resistance vessels) and that of the shunts inside the angioma; consequently, vascular resistance increased. Transcranial Doppler sonographic recordings showed a decrease in blood flow velocity as compared to pathologically increased blood flow velocity in angiomas, and a gradual increase in vascular resistance which was lower before treatment.