'Full dose' reirradiation of human cervical spinal cord

Risk of Myelopathy Following Second Local Treatment after Initial Irradiation of Spine Metastasis

Metastatic lesions of the spine occur in up to 40% of cancer patients and are a frequent source of pain and neurologic deficit due to cord compression. Palliative radiotherapy is the main first-intent local treatment in the form of single-fraction radiotherapy or fractionated courses. Reirradiation is a viable option for inoperable patients where spinal decompression is needed but with an increased risk of radiation-induced myelopathy (RM) and subsequent neurologic damage. This review summarizes reported data on local treatment options after initial irradiation in patients with relapsed spine metastasis and key dosimetric correlations between the risk of spinal cord injury and reirradiation technique, total dose, and time between treatments. The Linear Quadratic (LQ) model was used to convert all the published doses into biologically effective doses and normalize them to EQD2. For 3D radiotherapy, authors used cumulative doses from 55.2 Gy2/2 to 65.5 Gy2/2 EQD2 with no cases of RM mentioned. We found little evidence of RM after SBRT in the papers that met our criteria of inclusion, usually at the median reported dose to critical neural tissue around 93.5 Gy2/2. There is a lack of consistency in reporting the spinal cord dose, which leads to difficulty in pooling data.

Spinal Radiosurgery for Metastatic Disease of the Spine

Background

Metastatic tumor in the spinal column is common, causing symptomatic spinal cord compression in approximately 25,000 patients annually. Although surgical treatment of spinal metastases has become safer, less invasive, and more efficacious in recent years, there remains a subset of patients for whom other treatment modalities are needed. Stereotactic radiosurgery, which has long been used in the treatment of intracranial lesions, has recently been applied to the spine and enables the effective treatment of metastatic lesions.

Methods

We review the evolution of stereotactic radiosurgery and its applications in the spine, including a description of two commercially available systems.

Results

Although a relatively new technique, the use of stereotactic radiosurgery in the spine has advanced rapidly in the past decade. Spinal stereotactic radiosurgery is an effective and safe modality for the treatment of spinal metastatic disease.

Conclusions

Future challenges involve the refinement of noninvasive fiducial tracking systems and the discernment of optimal doses needed to treat various lesions. Additionally, dose-tolerance limits of normal structures need to be further developed. Increased experience will likely make stereotactic radiosurgery of the spine an important treatment modality for a variety of metastatic lesions.

Reirradiation of the spine with stereotactic radiosurgery: Efficacy and toxicity

PURPOSE

To determine the potential benefits and adverse effects associated with reirradiating the spinal cord when at least 1 course of radiation therapy (RT) is stereotactic radiosurgery (SRS).

METHODS AND MATERIALS

This institutional review board-approved retrospective review included 162 patients (237 reirradiated spine lesions). All patients received SRS at our institution between 2001 and 2013. Electronic medical records were reviewed for clinical exams and radiologic tests (computed tomography/magnetic resonance imaging). Primary endpoints were pain, neurological, radiographic responses, and the development of adverse effects.

RESULTS

A total of 120 patients (74.1%) were deceased with a median survival of 13 months. Time between courses of RT was a median of 10.2 months. Median SRS dose was 16 Gy in 1 fraction, whereas the median conventional external beam radiation therapy (cEBRT) dose was 30 Gy in 10 fractions. The median tumor equivalent dose in 2-Gy fractions (EQD2) for SRS doses was 34.7 Gy, whereas the median tumor EQD2 for cEBRT was 32.5 Gy, providing a median total tumor EQD2 of 69.3 Gy (22-145.6 Gy). The median critical nervous tissue EQD2 for SRS and cEBRT was 56 Gy and 37.5 Gy, respectively, resulting in a median total critical nervous tissue EQD2 of 93.5 Gy. Overall pain, neurological, and radiographic response rates were 81%, 82%, and 71%, respectively. Adverse effects occurred in 11 (6.8%) patients. Seventy-seven vertebral compression fractures were observed, 22 (9.3%) of which may be attributed to RT.

CONCLUSIONS

Our results demonstrate that reirradiation achieves favorable response rates with minimal toxicity if recommended dose constraints to the spinal cord with SRS are carefully observed. To the best of our knowledge, this is the largest reported single-institution experience analyzing the efficacy and toxicity of reirradiation of the spine when at least 1 course of RT is stereotactic radiosurgery.

Image-Guided Radiosurgery of Head and Neck Cancers

OBJECTIVES: Radiosurgery precisely delivers a single high dose or a few fractionated doses of radiation to a localized tumor via the stereotactic approach. Some head and neck sites are suitable for radiosurgery since there is minimal or no organ motion. The clinical studies were carried out to determine the accuracy of stereotactic radiosurgery and to demonstrate the effectiveness of radiosurgery in head and neck cancers.

MATERIALS AND METHODS: Thirteen patients were treated with either single-dose or fractionated radio-surgery to the tumor. All patients except one with cancer of the lip had received prior treatments including surgery, radiotherapy, and chemotherapy for the primary cancers. The dose ranged 12 to 18 Gy for single-dose radiosurgery and 30 Gy in 5 or 6 fractions twice a week for fractionated radiosurgery. Tumor localization was achieved via the stereotactic approach.

RESULTS: Accuracy of radiosurgery was within 1.5 mm. Despite the recurrent disease from previous heavy treatments, 9 patients (70%) showed a significant response (complete or >50% tumor reduction) to radiosurgery, and 3 patients had stable disease. Complete tumor response was achieved in 6 patients. All patients had excellent pain relief with functional and cosmetic preservation. There was no acute and subacute radiation toxicity detected clinically during the minimal follow-up of 6 months.

CONCLUSION: Image-guided radiosurgery is effective in achieving the local tumor control and pain relief. Radiosurgery provided excellent functional and cosmetic preservation with minimal complication. The results indicate the potential of radiosurgery in the treatment of recurrent and selected primary head and neck cancers. (Otolaryngol Head Neck Surg 2004;130:690-7.)

Stereotactic Radiotherapy for Cervical Spinal Intramedullary Metastasis and Multiple Brain Metastases: A Case Report

A case of cervical (C) spinal intramedullary metastasis and multiple small brain metastases from papillary thyroid carcinoma was presented. Spinal metastasis caused posterior neck and left shoulder pain, dysesthesia in both legs, and motor weakness in both legs and left arm, though the brain metastases were asymptomatic. Both the spinal and brain metastases were successfully treated by frameless stereotactic radiotherapy (SRT)/stereotactic radiosurgery (SRS). The patient's symptoms were almost entirely relieved within two months.

A 76-year-old woman was diagnosed as having a thyroid tumor and lung metastasis by roentgenography and computed tomography. Biopsy of the thyroid tumor extending into the mediastinum revealed papillary thyroid carcinoma. She underwent surgical resection of thyroid with dissection of the mediastinum lymph node area. Internal oral radioisotope therapy was not effective for the multiple small lung metastases. She did well for 15 months, but later developed posterior neck and left shoulder pain and dysesthesia in the right leg and then dysesthesia and motor weakness in both legs. Then she experienced weakness in the left upper extremity. Magnetic resonance imaging (MRI) disclosed a small cervical spinal intramedullary mass lesion at the level of C6 and C7 on the left side as well as nine small brain lesions. The cervical spinal intramedullary metastatic tumor was treated by volumetric modulated arc radiotherapy (VMAT) SRT and the nine small brain metastatic tumors were treated by dynamic conformal arc (DCA) SRS uneventfully. A total dose of 39 Gy (100% dose) was delivered in 13 fractions for the spinal lesion (prescription, D95=95% dose; maximum dose=46.3 Gy). Single fraction SRS of 22 Gy (prescription, D95=100% dose) was performed for each of the nine small brain tumors. The spinal tumor was decreased in size on follow-up MRI two months after SRT. Three of the nine brain lesions had disappeared and six were decreased in size on follow-up MRI two months after SRS. Motor weakness in the left extremities and right leg was fully improved, and she could walk again without a cane within two months after SRT. She had only slight dysesthesia in the right leg, possibly due to lumbar spondylosis at the end of the six-month follow-up after SRT. The spinal tumor continued to decrease in size on follow-up MRI five months after SRT. Eight of the nine brain lesions had disappeared and one was decreased in size on follow-up MRI five months after SRS.

Overall survival after reirradiation of spinal metastases - independent validation of predictive models

BACKGROUND

It is unknown if survival prediction tools (SPTs) sufficiently predict survival in patients who undergo palliative reirradiation of spinal metastases. We therefore set out to clarify if SPTs can predict survival in this patient population.

METHODS

We retrospectively analyzed spinal reirradiations performed (n = 58, 52 patients, 44 included in analysis). SPTs for patients with spinal metastases were identified and compared to a general palliative score and to a dedicated SPT to estimate prognosis in palliative reirradiation independent of site (SPT-Nieder).

RESULTS

Consistently in all tests, SPT-Nieder showed best predictive performance as compared to other tools. Items associated with survival were general condition (KPS), liver metastases, and steroid use. Other factors like primary tumor site, pleural effusion, and bone metastases were not correlated with survival. We adapted an own score to the data which performed comparable to SPT-Nieder but avoids the pleural effusion item. Both scores showed good performance in identifying long-term survivors with late recurrences.

CONCLUSIONS

Survival prediction in case of spinal reirradiation is possible with sufficient predictive separation. Applying SPTs in case of reirradiation helps to identify patients with good life expectancy who might benefit from dose escalation or longer treatment courses.

Impact of dose on local failure rates after image-guided reirradiation of recurrent paraspinal metastases

PURPOSE

To examine the impact of dose on local failure (LF) rates in the re-treatment of recurrent paraspinal metastases with image-guided intensity-modulated radiotherapy (IG-IMRT).

METHODS AND MATERIALS

The records of patients with in-field recurrence after previous spine radiation (median dose, 30 Gy) who received salvage IG-IMRT with either five 4-Gy (20-Gy group, n = 42) or five 6-Gy (30-Gy group, n = 55) daily fractions between January 2003 and August 2008 were reviewed. Institutional practice was 20 Gy before April 2006, when it changed to 30 Gy. A total of 47 cases (48%) were treated adjuvantly, after surgery to decompress epidural disease. LF after IG-IMRT was defined radiographically.

RESULTS

The median follow-up was 12.1 months (range, 0.2-63.6 months). The 1-year cumulative incidences of LF after 20 Gy and 30 Gy IG-IMRT were 45% and 26%, respectively (p = 0.04). Of all treatment characteristics examined (20-Gy vs. 30-Gy dose group, dose to 95% of the planned and gross target volume, tumor size, histology, receipt of surgery, and interval between first and second radiation), only dose group had a significant impact on actuarial LF incidence (p = 0.04; unadjusted HR, 0.51; 95% CI, 0.27-0.96). There was no incidence of myelopathy.

CONCLUSIONS

A significant decrease in LF after IG-IMRT with five 6-Gy fractions compared with five 4-Gy fractions was observed without increased risk of myelopathy. Until prospective data comparing stereotactic hypofractionated and single-fraction regimens become available, when reirradiating recurrent paraspinal metastases with IG-IMRT, administration of five 6-Gy daily fractions is reasonable.

Review of spinal radiosurgery: a minimally invasive approach for the treatment of spinal and paraspinal metastases

Intracranial radiosurgery has been proved effective for the treatment of brain metastasis. The treatment of paraspinal and spinal metastasis with spinal radiosurgery represents a natural extension of the principles of intracranial radiosurgery. However, spinal radiosurgery is a far more complicated process than intracranial radiosurgery. Larger treatment volumes, numerous organs at risk, and the inability to utilize rigid, frame-based immobilization all contribute to the substantially more complex process of spinal radiosurgery.

Beyond the convenience of a shorter duration of treatment for the patient, spinal radiosurgery affords a greater biological equivalent dose to a metastatic lesion than conventional radiotherapy fractionation schemes. This appears to translate into a high rate of tumor control and fast pain relief for patients. The minimally invasive nature of this approach is consistent with trends in open spinal surgery and helps to maintain or improve a patient's quality of life. Spinal radiosurgery has expanded the neurosurgical treatment armamentarium for patients with spinal and paraspinal metastasis.

Pain control by image-guided radiosurgery for solitary spinal metastasis

Precision and accuracy of image-guided spinal radiosurgery has been previously demonstrated. This study was carried out to determine the clinical efficacy of spine radiosurgery for the treatment of solitary spinal metastases with or without cord compression. A total of 49 patients with 61 separate spinal metastases were treated with radiosurgery. All patients had pathologically proven primary cancers and had either synchronous or metachronous metastasis to the spine. The majority of the patients presented with back pain. All patients received single-dose radiosurgery to the involved spine only. The radiosurgery dose ranged from 10 to 16Gy. The primary endpoint was pain control, but outcomes in neurological status and radiological tumor control also were assessed. The median time to pain relief was 14 days and the earliest time of pain relief was within 24hours. Complete pain relief was achieved in 46%, partial relief in 18.9%, and stable symptoms in 16.2%. Relapse of pain at the treated spinal segment was 6.9%. Median duration of pain relief at the treated spine was 13.3 months. Overall pain control rate for one year was 84%. This experience demonstrates that spinal radiosurgery can achieve rapid and durable pain relief. Single-dose radiosurgery has a potential to be a viable treatment option for single spinal metastasis.

Partial volume tolerance of the spinal cord and complications of single-dose radiosurgery

BACKGROUND

Spine radiosurgery causes a rapid dose fall-off within the spinal cord. The tolerance of partial volume of the spinal cord may determine the extent of clinical application. The study analyzed the partial volume tolerance of the human spinal cord to single fraction radiosurgery.

METHODS

A total of 230 lesions with spine metastases in 177 patients were treated with radiosurgery with single fraction of 8 to 18 Gy, prescribed to the 90% isodose line that encompassed the target volume. Spinal cord volume was defined as 6 mm above and below the radiosurgery target volume. Spinal cord dose was calculated from the radiation dose/spinal cord volume histogram and correlated with clinical/neurological status and radiographic studies. Median follow-up was 6.4 months (range, 0.5-49 months). The 1-year survival rate was 49%.

RESULTS

The average spinal cord volume defined at the treated spinal segment was 5.9 +/- 2.2 mL. The average dose to the 10% spinal cord volume was 9.8 +/- 1.5 Gy, calculated from the dose-volume histogram in the group of 18 Gy prescribed dose. The spinal cord volume that received higher than 80% of the prescribed dose was 0.07 +/- 0.10 mL, which represented 1.3 +/- 1.8% of the cord volume. Among the 86 patients who survived longer than 1 year there was 1 case of radiation-induced cord injury after 13 months of radiosurgery. There were no other cases of spinal cord sequelae.

CONCLUSIONS

Whereas the maximum spinal cord tolerance to single-dose radiation is not known, partial volume tolerance of the human spinal cord is at least 10 Gy to 10% of the spinal cord volume defined as 6 mm above and below the radiosurgery target.

Mitigation of radiation-induced optic neuropathy in rats by ACE inhibitor ramipril: importance of ramipril dose and treatment time

PURPOSE

Radiation-induced optic nerve damage was reduced by ramipril, a prodrug angiotensin-converting enzyme inhibitor (ACEI). This study was to determine the optimum dose and administration time of ramipril for mitigating radiation-induced optic neuropathy.

MATERIALS AND METHOD

Adult Fischer 344 male rats were treated with a single dose radiation 30 Gy by using radiosurgical technique. After irradiation, the animals were randomly assigned into groups of different ramipril doses and administration time; control (no treatment), radiation alone, radiation+ramipril in different doses and starting times of drug. Ramipril was given 0.5-1.5 mg/kg/day and AT1R blocker Losartan 20 mg/kg/day in drinking water for 180 days. Functional endpoint with visual evoked potential (VEP) and anatomical endpoint with gross and histological analysis with immunohistochemical (IHC) stain were used.

RESULTS

Normal VEP measurements in un-irradiated rats were 46.2+/-7.9 ms. There was no change of VEP value until 4 months, but was lengthened to 188.1+/-58.7 ms at 6 months after radiation. By ramipril treatment with the dose of 1.5 mg starting at 2 weeks after radiation, VEP was significantly shortened to 105.7+/-88.5 ms at 6 months. Gross and microscopic structure of the irradiated optic nerve was well preserved in the ramipril-treated group.

CONCLUSION

Ramipril can mitigate the radiation-induced optic nerve damage and preserve the functional integrity of the nerve. The results support early treatment with a high dose of ramipril after radiation.

Spinal reirradiation after short-course RT for metastatic spinal cord compression

PURPOSE

To investigate the feasibility and effectiveness of reirradiation (re-RT) for in-field recurrence of metastatic spinal cord compression after primary RT with 1 x 8 Gy or 5 x 4 Gy.

METHODS AND MATERIALS

A total of 62 patients, treated with 1 x 8 Gy (n = 34) or 5 x 4 Gy (n = 28) between January 1995 and August 2003, received re-RT for in-field recurrence of metastatic spinal cord compression. The median time to recurrence was 6 months (range, 2-40 months). Re-RT was performed with 1 x 8 Gy (after 1 x 8 Gy or 5 x 4 Gy, n = 34), 5 x 3 Gy (after 1 x 8 Gy or 5 x 4 Gy, n = 15), or 5 x 4 Gy (after 1 x 8 Gy, n = 13). The cumulative biologically effective dose (primary RT plus re-RT) was 80-100 Gy2. The median follow-up after re-RT was 8 months (range, 2-42 months). Motor function was evaluated up to 6 months after re-RT.

RESULTS

After re-RT, 25 patients (40%) showed improvement of motor function, 28 (45%) had no change, and 9 (15%) had deterioration. Of the 16 previously nonambulatory patients, 6 (38%) regained the ability to walk. No second in-field recurrence in the same spinal region was observed after re-RT. The outcome was not significantly influenced by the radiation schedule. Radiation myelopathy was not observed.

CONCLUSIONS

Spinal re-RT with 1 x 8 Gy, 5 x 3 Gy, or 5 x 4 Gy for in-field recurrence of metastatic spinal cord compression appears safe and effective. Myelopathy seems unlikely, if the cumulative biologically effective dose is < or = 100 Gy2.

Proposal of human spinal cord reirradiation dose based on collection of data from 40 patients

PURPOSE

Driven by numerous reports on recovery of occult radiation injury, reirradiation of the spinal cord today is considered a realistic option. In rodents, long-term recovery was observed to start at approximately 8 weeks. However, prospective clinical studies are lacking. Therefore, a combined analysis of all published clinical data might provide a valuable basis for future trials.

METHODS AND MATERIALS

We collected data from 40 individual patients published in eight different reports after a comprehensive MEDLINE search. These represent all patients with data available for dose per fraction and total dose of each of both treatment courses. We recalculated the biologically effective dose (BED) according to the linear-quadratic model using an alpha/beta value of 2 Gy for the cervical and thoracic cord and 4 Gy for the lumbar cord. In this model, a dose of 50 Gy given in single daily fractions of 2 Gy is equivalent to a BED of 100 Gy(2) or 75 Gy(4). For treatment with two daily fractions, a correction term was introduced to take incomplete repair of sublethal damage into account.

RESULTS

The cumulative doses ranged from 108 to 205 Gy(2) (median dose, 135 Gy(2)). The median interval between both series was 20 months. Three patients were treated to the lumbar segments only. The median follow-up was 17 months for patients without myelopathy. Eleven patients developed myelopathy after 4-25 months (median, 11 months). Myelopathy was seen only in patients who had received one course to a dose of > or =102 Gy(2) (n = 9) or were retreated after 2 months (n = 2). In the absence of these two risk factors, no myelopathy developed in 19 patients treated with < or =135.5 Gy(2) or 7 patients treated with 136-150 Gy(2). A risk score based on the cumulative BED, the greatest BED for all treatment series in a particular individual, and interval was developed. Low-risk patients remained free of myelopathy and 33% of intermediate-risk patients and 90% of high-risk patients developed myelopathy.

CONCLUSION

On the basis of these literature data (and with due caution), the risk of myelopathy appears small after < or =135.5 Gy(2) when the interval is not shorter than 6 months and the dose of each course is < or =98 Gy(2). We would recommend limiting the dose to this level, whenever technically feasible. However, it appears prudent to propose the collection of prospective data from a greater number of patients receiving doses in the range of 136-150 Gy(2) to assess the safety of higher retreatment doses for those patients in whom limited doses might compromise tumor control.

Novalis radiosurgery for metastatic spine tumors

It is logical to anticipate that the field of spinal radiosurgery will evolve in a fashion similar to that seen for intracranial radiosurgery. Given the frequency of various pathologic entities that affect the spine, including those that have proven to be largely intractable to surgery, radiation, and chemotherapy (eg, sarcomas), and the serious clinical, economic and quality-of-life consequences of paraplegia, radiosurgery offers new hope as an adjuvant or primary therapy. The meticulous application of well-designed investigations of relevant clinical outcomes will be critical to the appropriate and effective use of this technology.

Simultaneous development of bilateral retrobulbar and intradural spinal masses following donor lymphocyte infusions for acute lymphoblastic leukemia relapsing after bone marrow transplantation

The authors describe a 6-year-old boy with acute lymphoblastic leukemia in relapse after bone marrow transplantation. Complete remission was obtained after reinduction chemotherapy followed by donor lymphocyte infusions. Ten months later, right-sided proptosis and exotropia developed, with back pain and leg paralysis. Computed tomography revealed bilateral orbital masses. Magnetic resonance imaging demonstrated abnormal signal intensity in the T4-6 vertebral bodies and an intradural mass on the left posterior side of the spinal canal. Although bone marrow aspiration was negative, orbital mass biopsies revealed CD10-positive lymphoblasts. Chimerism analysis of bone marrow and peripheral blood showed full donor alleles. Local radiotherapy and chemotherapy resulted in neurologic improvement.

Prophylactic hyperbaric oxygen treatment and rat spinal cord re-irradiation

Normal tissue injury may lead to severe, life threatening, late side effects after therapeutic use of irradiation. Neurological complications caused by radiation of the spinal cord are ascribed to progressive, irreversible damage to the vasculature. Hyperbaric oxygen (HBO) is known to induce angiogenesis in irradiated tissue and has been proven to reduce late radiation injury in several normal tissues when applied during the latent period before complications become manifest. In the present study: (1). the prophylactic potential of HBO; (2). optimal timing of HBO therapy after spinal cord irradiation, i.e. during the latent period; and (3). effect of HBO on the re-irradiation tolerance of the spinal cord were investigated. The rat cervical spinal cord was locally X-ray irradiated with ten fractions of 6.5 Gy in 11 days. Five treatment groups (n=10) included: irradiation alone and irradiation followed by 30 HBO treatments (100% oxygen at 240 kPa for 90 min) during latency, with HBO starting either immediately, 5, 10 or 15 weeks after the primary irradiation course. One year after the primary treatment, the same spinal cord volume was re-irradiated with 20 Gy single dose. During life span, the animals were observed on the incidence of myelitis and the duration of the latent period. The actuarial analysis revealed no significant difference in neurological complications free survival between the irradiation alone and the irradiation+HBO treatment groups. A tendency towards radiosensitization was found in the group in which the primary irradiation course was immediately followed by the HBO treatment course. The data show that HBO applied during the latent period of progressively developing irradiation damage to the spinal cord does not increase the re-irradiation tolerance of this tissue.

Intensity-modulated radiation therapy for the spine at the University of California, Irvine

Radiation treatment of malignant diseases of the spine poses unique challenges to the radiation oncology treatment team. Intensity-modulated radiation therapy (IMRT) offers the capability of delivering high doses to targets near the spine while respecting spinal cord tolerance. At the University of California, Irvine, 8 patients received a total of 10 courses to the spine for a variety of primary and metastatic malignant conditions. This paper discusses anatomical considerations, spinal cord radiation myelopathy, and treatment planning issues as it relates to the treatment of spinal cord lesions. Between October 1997 and August 2001, a total of 8 patients received 10 courses of IMRT for primary or metastatic disease of the spine. Cancers treated included metastatic lung, renal, adrenocortical cancers, and primary sarcomas and giant cell tumor. Five cases had 6 courses given for re-irradiation of symptomatic disease and 3 cases had 4 courses of IMRT as primary management of their spinal lesions. Although 3 courses were given postoperatively, these were for grossly residual disease. For the re-irradiation patients, the mean follow-up interval was 4 months. The local control was estimated at 14%. Of the patients treated with primary intent, the mean follow-up was 9 months and the local control rate 75%. No patients developed spinal cord complications.

Radiosurgical treatment for Ewing's sarcoma of the lumbar spine: case report

STUDY DESIGN

Case report.

OBJECTIVES

The objective of this study was to document the long-term follow-up of a single case.

SUMMARY OF BACKGROUND DATA

Radiosurgery is potentially a useful therapeutic option for spinal tumors. The authors present the unusual case of a patient with recurrent extraosseous Ewing's sarcoma of the lumbar spine, who experienced excellent clinical, radiographic, and oncologic response without complications after treatment with dedicated Novalis Shaped Beam Radiosurgery (Brain Lab, Inc.).

METHODS

Observational.

RESULTS

We observed excellent clinical and oncologic control at 1-year posttreatment.

CONCLUSION

Radiosurgery may be a valuable treatment option for recurrent spinal tumors.

Intramedullary plasma cell granuloma in the cervicothoracic spine

✓ Intraspinal plasma cell granuloma, which is a nonneoplastic entity, is extremely rare. To date, only four cases have been documented in the spinal meninges. The authors report the first case of a C7—T1 intramedullary plasma cell granuloma. After excision of the lesion, the patient's gait and bladder dysfunction improved. This plasma cell granuloma initially showed no delineated mass on T1-weighted magnetic resonance (MR) images, low signal intensity on T2-weighted images, and was well enhanced after administration of gadolinium diethylenetriamine pentaacetic acid. The latter MR imaging modality should help to detect this tumorous lesion. Histologically, the granuloma needs to be distinguished from lymphoplasmacyte-rich meningioma and plasmacytoma.

Radiation injury to the nervous system

This article reviews the current knowledge with regard to neurotoxicity of conventional radiation, including recent understanding of the pathophysiology, molecular biology, diagnostic evaluation and clinical presentations, as well as proposed treatment modalities and possible protective agents.