Low-dose craniospinal radiation therapy for medulloblastoma

At the University of California, San Francisco, 65 children with medulloblastoma of the posterior fossa were treated postoperatively with craniospinal irradiation; the dose to the posterior fossa was 54 Gy. The 26 children initially treated had only radiation therapy, receiving 30 to 40 Gy to the spine and 40 to 50 Gy to the brain. Subsequently, 39 children were treated with low-dose craniospinal irradiation and chemotherapy; 24 to 30 Gy was directed to the whole brain and 24 to 26 Gy to the spinal axis. Chemotherapy generally consisted of procarbazine just before, and hydroxyurea during, radiation therapy. Poor-risk and good-risk patients (defined by tumor resection less than 75% or greater than 75%, positive or negative myelogram, positive or negative cerebrospinal fluid analysis, age less than or greater than 2 years, respectively) were evenly distributed between the low-dose and high-dose craniospinal radiation therapy groups. Median follow-up was 51 months (range, 24 to 228 months). Kaplan-Meier actuarial survival for all patients was 73% at 5 years, 70% at 10 years. Freedom from disease progression was 68% at 5 years, 65% at 10 years. Whereas poor-risk patients treated with low-dose craniospinal irradiation and chemotherapy had a 5-year survival of 58% and a 5-year freedom from disease progression of 39%, those figures in the comparable good-risk patients were 83% and 77%, respectively. For both good-risk and poor-risk patients, the posterior fossa was the primary site of recurrence. Tumors recurred in the frontal region, probably under blocks, in three patients receiving low-dose irradiation and in two receiving the higher dose. Reducing the dose of whole-brain and spinal irradiation and giving chemotherapy did not result in a higher rate of recurrence in the brain or spinal cord. Intellectual and social function appeared better in patients receiving the lower dose. We did not study whether chemotherapy benefitted good-risk patients. Craniospinal axis irradiation at a lower dose than conventionally used does not compromise local control or survival in patients with medulloblastoma, and may reduce toxicity.     

Results of radiation therapy for medulloblastoma

Results of radiation therapy for cerebellar medulloblastoma at Kyoto University Hospital were reviewed. Between 1962 and 1988, 30 patients with histologically-proven medulloblastoma completed radiotherapy. Before 1971, the treatment volume was either the posterior fossa only or posterior fossa plus spinal axis, but after 1972, it was extended to include the entire neuraxis. The mean dose was 48 Gy to the posterior fossa, 36 Gy to the whole brain, and 25 Gy to the spinal axis. The 5-year survival rate and 5-year relapse-free survival rate estimated by the Kaplan-Meier's method were 36% and 37%, respectively, for total cases, but were as high as 79% and 80%, respectively, for the recent 10 patients. This improvement in the treatment results appeared to be due to extensive tumor resection and improved radiotherapy technique, and not to the use of chemotherapy. The prognosis was significantly better in patients treated with craniospinal irradiation than in those otherwise treated. There was a trend towards better survival in patients who received 50 Gy or more to the posterior fossa or 24 Gy or more to the spinal axis, compared to the patients who received lower doses to each site. No significant morbidity of radiotherapy was seen. Four of the six surviving patients who were treated below age 12 have a mental retardation and/or a short stature, but one patient treated at age 5 has a normal growth and a good intelligence. From these analysis, it is recommended to irradiate craniospinal axis and posterior fossa up to 25-35 Gy and 50-55 Gy, respectively.     

Radiation-induced esophageal carcinoma 30 years after mediastinal irradiation: case report and review of the literature

A 54-year-old man who had been irradiated in 1964 for cervical involvement by Hodgkin's disease was admitted in December 1994 to our clinic with strong complaints of dysphagia. The reason was a moderately differentiated squamous cell carcinoma of the proximal esophagus in the previously irradiated region. The patient had no risk factors (abuse of nicotine or alcohol) for the developement of esophageal carcinoma. A reirradiation was performed, but the disease progressed locally and two weeks after the beginning of the therapy the patient developed two tracheoesophagocutaneous fistulae. The radiation therapy was discontinued and the tumor stenosis was bridged by a tube closing the fistulae. A retrospective dose analysis to evaluate the applied doses will be performed. Furthermore, an overview of 66 cases of the literature with radiation-induced esophageal carcinoma analysed concerning applied dose and latent interval will be given. In conclusion the reported case fits the criteria for radiation-induced malignancies (Chudecki Br J Radiol 1972;45:303-4) known from literature: (1) a history of previous irradiation, (2) a cancer occurring within the irradiated area, (3) gross tissue damage due to an excessive dose of radiation, and (4) a long latent interval between irradiation and development of cancer. Esophageal carcinomas belong to the rare secondary malignancies after the therapeutic use of ionizing radiation. Nevertheless in patients with dysphagia they should be suspected as a differential diagnosis even many years after mediastinal irradiation. The treatment of these tumors is very difficult and is associated with a poor prognosis.     

Intensity-modulated radiation therapy for pediatric medulloblastoma: early report on the reduction of ototoxicity

PURPOSE: The combination of cisplatin chemotherapy and radiation therapy for the treatment of medulloblastoma has been shown to cause significant ototoxicity, impairing a child's cognitive function and quality of life. Our purpose is to determine whether the new conformal technique of intensity-modulated radiation therapy (IMRT) can achieve lower rates of hearing loss by decreasing the radiation dose delivered to the cochlea and eighth cranial nerve (auditory apparatus). PATIENTS AND METHODS: Twenty-six pediatric patients treated for medulloblastoma were retrospectively divided into two groups that received either conventional radiotherapy (Conventional-RT Group) or IMRT (IMRT Group). One hundred thirteen pure-tone audiograms were evaluated retrospectively, and hearing function was graded on a scale of 0 to 4 according to the Pediatric Oncology Group's toxicity criteria. Statistical analysis comparing the rates of ototoxicity was performed using Fisher's exact test with two-tailed analysis. RESULTS: When compared to conventional radiotherapy, IMRT delivered 68% of the radiation dose to the auditory apparatus (mean dose: 36.7 vs. 54.2 Gy). Audiometric evaluation showed that mean decibel hearing thresholds of the IMRT Group were lower at every frequency compared to those of the Conventional-RT Group, despite having higher cumulative doses of cisplatin. The overall incidence of ototoxicity was lower in the IMRT Group. Thirteen percent of the IMRT Group had Grade 3 or 4 hearing loss, compared to 64% of the Conventional-RT Group (p < 0.014). CONCLUSION: The conformal technique of IMRT delivered much lower doses of radiation to the auditory apparatus, while still delivering full doses to the desired target volume. Our findings suggest that, despite higher doses of cisplatin, and despite radiotherapy before cisplatin therapy, treatment with IMRT can achieve a lower rate of hearing loss.     

Radiation-induced undifferentiated pleomorphic sarcoma after radiation therapy for a desmoid tumour

Radiation-induced sarcoma is a long-term complication of radiation therapy. The most common secondary neoplasia is the undifferentiated pleomorphic sarcoma, which is usually described in the deep soft tissue of the trunk or extremities. Radiation-induced sarcomas have a poor prognosis. An early diagnosis and management are needed to improve the survival rate of such patients. We presently report a case of a radiation-induced undifferentiated pleomorphic sarcoma of the left gluteus maximus muscle, which developed 25 years after an initial diagnosis of aggressive fibromatosis and 21 years after a tumour recurrence. This case study illustrates the risk of developing a sarcoma in a radiation field and the need for long-term follow-up after radiation therapy. Unnecessary radiation therapy, in particular in the case of benign conditions in young patients, should be avoided.     

Hepatic angiosarcoma occurring after cyclophosphamide therapy: case report and review of the literature

A 54-year-old man with polyarteritis nodosa developed acute onset of right upper quadrant abdominal pain associated with a large liver mass. Transvenous liver biopsy revealed hepatic angiosarcoma, a rare liver tumor classically associated with environmental toxins. He had been treated with oral cyclophosphamide for 13 years. A review of the literature revealed two other cases of hepatic angiosarcoma in patients after long-term cyclophosphamide treatment. We propose that cyclophosphamide be added to the list of exposures potentially associated with hepatic angiosarcoma.     

Radiation-induced adult medulloblastoma: a two-case report and review of the literature

Radiation-induced medulloblastoma is an exceedingly rare phenomenon for which treatment standards have not been established. The literature suggests that these tumors are high grade with aggressive behavior. We report two cases of radiation-induced medulloblastoma which have been treated with full dose re-irradiation with curative intent. In both cases, treatment toxicity and tumor progression proved to be insurmountable obstacles. Further reports are necessary in order to fully characterize this clinical entity so that more effective therapies may be sought.     

Preliminary results of conformal radiation therapy for medulloblastoma

Radiation therapy for medulloblastoma consists of postoperative irradiation of the intracranial and spinal subarachnoid volume with an additional boost to the primary site of disease in the posterior fossa. The entire posterior fossa is usually included in the boost volume. Conformal radiation therapy techniques may be used to boost the primary site alone and substantially reduce the dose received by normal tissues, including the supratentorial brain, the middle and inner ear, and the hypothalamus. Using these techniques to irradiate only the tumor bed or residual tumor and not the entire posterior fossa represents a new paradigm in the treatment of medulloblastoma. In this study, we examine the use of conformal radiation therapy in the treatment of 14 patients with medulloblastoma. These patients were treated with multiple static, individually shaped, noncoplanar beams directed at the primary site after craniospinal irradiation. Excluding two patients who had previously received irradiation to the posterior fossa, the mean dose delivered to the primary site was 5715 cGy. Among the medulloblastoma patients (n = 10) who received immediate postoperative radiation therapy, no failures have occurred with a median follow-up of 42 months (range from 30 to 54 months). To demonstrate the differences in the distribution of dose to normal tissues when comparing conventional and conformal techniques, dose-volume histograms of the total brain, middle and inner ear, hypothalamus, and temporal lobe were created and presented for an example case. The neurologic, neuroendocrine, and neurocognitive outcome for patients with medulloblastoma may be influenced with the use of conformal radiation therapy. The use of these techniques should be formally tested in prospective studies of rigorously staged patients with failure rate monitoring.     

Bronchiolitis obliterans organizing pneumonia after stereotactic ablative radiation therapy for lung cancer: A case report

Bronchiolitis obliterans organizing pneumonia is an interstitial lung disease rarely occurring after radiotherapy probably due to an activation of autoimmune processes. Most cases have been described after postoperative radiotherapy for breast cancer. Corticosteroids represent the main treatment, prognosis is generally favorable. We described a case of bronchiolitis obliterans organizing pneumonia after stereotactic ablative radiation therapy for a recurrent lung cancer. Antibiotics and steroids were administered to solve the clinical picture. After three years, a new lesion at the right lung was found and treated with stereotactic ablative radiation therapy and concomitant long course of steroids with no recurrence of bronchiolitis obliterans organizing pneumonia. Bronchiolitis obliterans organizing pneumonia is a rare event after radiotherapy with undefined risk factors. In our case, steroids played an important role in management and, maybe, in preventing bronchiolitis obliterans organizing pneumonia recurrence after second course of stereotactic ablative radiation therapy.     

Radiation-induced osteosarcoma in dogs after external beam or intraoperative radiation therapy

This report describes radiation-induced osteosarcomas in two groups of dogs. One group was given radiation therapy for spontaneous tumors and the second group of normal adult beagle dogs was given experimental intraoperative radiation therapy. Secondary tumors developed between 1.7 to 5 years after irradiation. Three of 87 spontaneous tumor-bearing dogs or 3.4% of dogs treated for soft tissue sarcomas developed osteosarcoma within the field of irradiation. Twenty-two dogs or 25% of dogs treated for soft tissue sarcomas survived 20 months. This high incidence may be due to the use of fractions in excess of 3.5 Gy. These dogs received 10 fractions in 3 weeks with fractions ranging from 3.5 to 5.0 Gy. Tumor induction may be included in the late effects of irradiation which are worsened by the use of coarse fractionation. There appeared to be a dose relationship for tumors induced after single intraoperative radiation doses combined with fractionated external beam irradiation. Seven of 27 dogs given this treatment and surviving at least 4 years developed osteosarcomas in the field of irradiation. One of 26 dogs given intraoperative radiation alone developed a tumor between 4 and 5 years. The lower incidence after intraoperative radiation alone may have been due to the lower total dose. However, the sequence of a course of fractionated irradiation followed by a large single dose seemed to enhance carcinogenicity.     

Gamma Knife radiosurgery after radiation therapy as an adjunctive treatment for glioblastoma

Despite a randomized trial showing no benefit of stereotactic radiosurgery (SRS) prior to radiation therapy (RT), the benefits of SRS after RT and at the time of progression require further characterization. We retrospectively reviewed 48 patients with histopathological diagnoses of glioblastoma (GBM) that were treated with SRS over a 16-year period (1991–2007). Twenty-two were treated as part of their initial treatment paradigm and 26 were treated at the time of progression. The primary endpoints studied were overall survival (OS), survival after SRS and time-to-progression (TTP). Patients treated at the time of progression had significantly longer OS than those treated on initial presentation (17.4 vs. 15.1 months, P = 0.003). On multivariate analysis, Radiation Therapy Oncology Group (RTOG) class III patients, those with more extensive resections, and those who were not on steroids at the time of SRS had significantly improved OS. SRS margin dose was a significant prognostic factor for TTP on multivariate analysis (HR = 0.78, 95% CI: 0.62–0.98). In the subgroup of patients treated with GKS as part of their initial treatment, an increasing number of weeks between surgical resection and GKS was a poor prognostic factor on multivariate analysis (HR = 1.11, 95% CI: 1.01–1.23). In patients who were treated with SRS at the time of progression, chemotherapy was associated with a longer TTP (P = 0.028). Our results suggest that SRS provides a survival advantage when delivered after RT. This benefit may be best appreciated in RTOG class III patients. Moreover, SRS may be a viable alternative to open surgery for aggressive management of GBM at the time of recurrence. Prospective studies of SRS for GBM should focus on these two groups of patients. Portions of this work were presented as proceedings at the Annual Meeting of the Neurosurgical Society of the Virginias, Hot Springs, Virginia, January 2006.     

Epithelioid glioblastoma: a case report

A 43-year-old woman who had undergone breast cancer surgery 1 year previously complained of headache and nausea. Her brain computed tomography (CT) scan and magnetic resonance imaging (MRI) showed a well-circumscribed, heterogeneously enhanced tumor in the right thalamus. She underwent gross total resection of the tumor followed by radiochemotherapy, and her clinical course was uneventful after surgery. Histological examination revealed a moderate number of tumor cells with fine bipolar processes in a mucoid matrix, which suggested pilocytic astrocytoma. The tumor was associated with microvascular proliferation but did not show significant mitosis or necrosis. In some areas, it had an epithelioid appearance, with ribbon-like, cribriform, and pseudoglandular patterns involving cuboid-shaped cells showing nuclear atypia and mitotic figures. Immunohistochemically, the tumor cells were positive for glial fibrillary acidic protein (GFAP) and vimentin in the area resembling pilocytic astrocytoma, but in the epithelioid area they were negative for GFAP and vimentin as well as for breast cancer markers, including AE1/AE3. The proliferating potential, represented by the MIB-1 labeling index, was high (82.5%) in the area of epithelioid appearance, compared to only 3% in the area of pilocytic astrocytoma-like appearance. As a rare histoarchitectural variant of glioblastoma, the epithelioid pattern may represent a very primitive tumor cell phenotype. Typically, this pattern is characterized by well-circumscribed masses, although its clinical significance is unknown.     

Acute hepatic vein thrombosis occurring during therapy for Hodgkin's disease: a case report

A case of fatal acute hepatic vein thrombosis occurred during treatment for Hodgkin's disease. At necropsy no evidence of Hodgkin's disease or obliterative venoocclusive disease of the liver was found. We speculate that Adriamycin, DTIC and/or vinblastine may have been responsible for this unusual disorder.     

Radiation induced adult medulloblastoma: a case report

Adult medulloblastoma is a rare intracranial tumor. Our patient is a 61 year old woman treated with cranial irradiation 15 years previously for a low grade astrocytoma in the left posterior temporal lobe that was recently diagnosed with medulloblastoma in the right cerebellum. This is the first reported case of radiation induced adult medulloblastoma.