Radiotherapy-induced lymphocytopenia: changes in total lymphocyte count and in lymphocyte subpopulations under pelvic irradiation in gynecologic neoplasms

Lymphocytopenia is one of the most negative biological prognostic factors in cancer patients. Lymphocytopenia may depend on tumor progression, or on various anticancer therapies. In particular, radiotherapy (RT) may induce direct lymphocyte damage. The present study was carried out to evaluate the influence of pelvic irradiation on lymphocyte number and lymphocyte subpopulations in patients with gynecologic tumors. The study included 40 patients affected by locally limited or advanced uterine tumors, who underwent pelvic irradiation for a total dose of 50.4 Gy. RT induced a significant decline in total lymphocyte number, with values lower than 500/mm3 in 29/40 (73%) patients and with a mean decrease of 71 +/- 4%. In the same way, T lymphocyte, CD4, CD8 and NK cell mean numbers significantly decreased under RT. The decline in NK and CD8 cells was limited to the first 2-3 weeks of irradiation, whereas that involving T lymphocytes and CD4 cells was progressive and persistent until the end of RT. Finally, the decline in total lymphocyte number was significantly greater in patients who had no tumor regression in response to RT. This study confirms that pelvic RT may induce severe lymphocytopenia which could negatively influence the efficacy of RT itself.     

Prolonged low dose IL-2 and thalidomide in progressive metastatic renal cell carcinoma with concurrent radiotherapy to bone and/or soft tissue metastasis: a phase II study

Metastatic renal cell cancer is one of the immuno-sensitive tumors. Apart from the immuno-modulating agents IFN and IL-2, thalidomide has been reported to be effective in this type of cancer. However, bone metastases and bulky metastases, show limited response to immunotherapy, are often site of recurrent disease and are therefore often treated later with radiotherapy. In this phase II study, we evaluated toxicity and efficacy of the combination of continuous low dose (1 mIU/m²) s.c. IL-2 and thalidomide (200 mg once daily) in 22 patients with progressive metastatic renal cell cancer. In addition, 13 soft tissue lesions and two bone metastases in 13 patients were concurrently treated with fractionated radiotherapy. T cell number and activation in blood was measured by immunoflowcytometry. Nearly all patients developed grade 1–2 toxicity consisting of fatigue, sensory neuropathy, constipation and dizziness. Five patients had a grade 3–4 toxic event: four patients with deep venous thrombosis requiring anticoagulant therapy, and one patient who developed radiation myelopathy. On systemic response evaluation ten patients showed ongoing SD with a mean progression free survival of 9 months. One patient showed a PR (at an irradiated site). Regarding local response to irradiation, seven lesions showed a PR for a mean time period of 8.7 months, whereas seven were stable for 6 months. The radiation response of one lesion was not evaluable. Immunoflowcytometry showed an increase in number and activation of lymphocytes (mainly Natural Killer—NK-cells), which was absent or even decreased in irradiated patients. The combination of sc. low dose IL-2, thalidomide and radiotherapy is feasible, but relatively toxic and does not lead to higher responses at non-irradiated sites. The combination of immunotherapy and concurrent radiotherapy is effective at 60% of the relatively large evaluable sites. Progressive myelopathy developed in one patient, possibly due to radiotherapy in combination with thalidomide.     

Pituitary Hormone Dysfunction After Proton Beam Radiation Therapy in Children with Brain Tumors

Objectiveo characterize endocrine dysfunction in pediatric patients with brain tumors who received proton beam (PB) radiation therapy and to compare those treated with PB radiotherapy only versus combined conventional and PB irradiation.MethodsA retrospective review of medical records of patients ≤ 18 years of age who received PB radiation therapy for a brain tumor between 2000 and 2008 was performed. Variables analyzed included patient demographics, tumor type, therapeutic modalities, radiation doses, and types and timing of endocrine dysfunction.ResultsThirty-eight patients were identified, of whom 31 (19 boys and 12 girls; mean age, 11.9 ± 3.3 years) had undergone endocrine evaluation. Of these patients, 19 received PB radiotherapy only and 12 received conventional plus PB irradiation. Before irradiation, a cranial surgical procedure was performed in 28 study subjects, and 22 received chemotherapy. The mean duration of follow-up after radiation therapy was 1.8 ± 0.8 years. Nine patients (47%) in the PB only group and 4 (33%) in the conventional plus PB group developed endocrine dysfunction (no significant difference) after cranial irradiation. Children with endocrine sequelae treated with PB irradiation alone received fewer cobalt gray equivalents than those treated with conventional plus PB irradiation (5,384 ± 268 versus 5,775 ± 226, respectively; P < .02), and pituitary hormone deficiencies were detected later during follow-up in those who received PB radiotherapy only versus conventional plus PB irradiation (1.17 ± 0.4 years versus 0.33 ± 0.11 year, respectively; P < .01).ConclusionA high rate of endocrine sequelae was seen in our study. Children with brain tumors treated with conventional plus PB irradiation developed endocrine dysfunction faster and received a higher radiation dose than those receiving PB radiotherapy only. Prior surgical treatment and chemotherapy were additional risk factors. Large prospective studies are needed to evaluate further the incidence of endocrine sequelae after PB irradiation in children. (Endocr Pract. 2011;17:891-896)     

Radiation-induced micronucleus frequency in peripheral blood lymphocytes is correlated with normal tissue damage in patients with cervical carcinoma undergoing radiotherapy

In an effort to find a test to predict the response of normal tissue to radiotherapy, the lymphocyte micronucleus assay was used on blood samples from patients with cervical carcinoma. Peripheral blood samples from 55 patients with advanced-stage (II B-IV B) cervical carcinoma were obtained before radiotherapy. The patients were treated with external-beam radiotherapy followed by high-dose-rate brachytherapy. Acute and late normal tissue reactions were scored and correlated with the micronucleus frequency in lymphocytes after irradiation with 4 Gy in vitro. Great interindividual variability was observed in the radiation-induced lymphocyte micronucleus frequency, especially at 4 Gy. The mean number of micronuclei per 100 binucleated cells in cells irradiated with 4 Gy in vitro was significantly higher in samples from patients who suffered from acute and/or late normal tissue reactions than in those from patients with no reactions (51.0 +/- 17.7 and 29.6 +/- 10.1, respectively). A significant correlation was also found between the micronucleus frequency at 4 Gy and the severity of acute reactions and late reactions. However, the overlap between the micronucleus frequencies of patients with high-grade late normal tissue reactions and low-grade reactions is too great to recommend the micronucleus assay in its present form for routine clinical application.     

Induction of micronuclei by 153Sm-EDTMP in peripheral blood lymphocytes of patients with bone metastases.

The purpose of this study was to evaluate the degree of cytological radiation damage to peripheral blood lymphocytes induced by 153Sm-EDTMP applied for palliation of metastatic bone pain. Blood samples from 16 patients (46-82 years old), 10 without previous radiotherapy and 6 with previous radiotherapy, were collected before and one hour after the administration of a mean activity of 41.7+/-5.8 MBq/kg of 153Sm-EDTMP. Then the lymphocytes were cultured for cytokinesis block micronucleus (MN) assay. The number of MNper binucleated cells (BC) in patients without previous radiotherapy before the treatment was of 0.030 (+/- 0.016) and after one hour 0.035 (+/- 0.013), although we could find inter individual differences. The basal MN/BC of the patients with no previous radiotherapy was similar to the controls. The increment in the percentage of BC with MN was similar in patients with and without previous radiotherapy. The observed mean of MN/BC is equivalent to a dose range of 0.05 to 0.10 Gy of 153Sm-EDTMP in vitro. The relatively low frequency of lymphocyte with micronuclei after the exposure to 153Sm-EDTMP supported the contention that radiation damage in lymphocytes of patients with painful bone metastases is minimal.     

食管癌患者放射治疗中照射体积和时间与外周血淋巴细胞绝对值的相关性研究

摘要 目的：探究照射体积和时间与食管癌患者外周血淋巴细胞绝对值的相关性。方法：本研究方案将纳入2019年1月~2019年12月蚌埠医学院第一附属医院放疗科收治的放疗或同步放化疗食管癌患者84例,其中单独放疗患者24例,同步放化疗患者60例,采用血液细胞分析仪测定患者放疗期间每周复查外周血白细胞（WBC）、中性粒细胞（N）、淋巴细胞（L）、血红蛋白（HB）及血小板（PLT）计数等指标。Pearson相关性分析照射时间、剂量及体积与外周血指标之间的相关性。结果：食管癌放疗患者,包括同步放化疗及单纯放疗亚组,在治疗1-6周,照射时间与外周血指标均无相关性（P>0.05）。但在放疗第5-6周,患者放疗剂量与WBC、N、L、HB呈负相关（P<0.05）,同步放化疗亚组患者照射剂量与WBC、N、L、HB呈负相关（P<0.05）。在治疗1-4周,不同照射剂量下各梯度照射剂量对应照射体积与外周血指标均无相关性（P>0.05）。但在第5-6周时,患者不同梯度照射剂量下各照射体积与WBC、N呈负相关（P<0.05）,同时在20Gy-60Gy照射剂量,尤其20Gy和30Gy照射剂量下照射体积与L呈负相关（P<0.05）。同步放化疗亚组患者不同照射剂量下各照射体积与WBC、N呈负相关（P<0.05）,同时在20Gy-60Gy照射剂量下照射体积与L呈负相关（P<0.05）,而且在60Gy照射剂量下照射体积与HB呈负相关（P<0.05）。结论：放疗患者特别是同步放化疗亚组患者照射体积、照射剂量与食管癌患者外周血淋巴细胞计数成负相关,基线淋巴细胞与食管癌患者外周血淋巴细胞计数成正相关,而照射时间与食管癌患者外周血淋巴细胞计数无相关性。     

External beam radiation therapy (EBRT) for patients with malignant pheochromocytoma and non-head and -neck paraganglioma: combination with 131I-MIBG

In patients with malignant pheochromocytoma and paraganglioma, 131I-MIBG radiotherapy can achieve an objective response rate of 30-50% with the dose limiting toxicity being hematologic. Patients with disseminated disease, who also have a few index bulky or symptomatic lesions, may benefit from the addition of targeted external beam radiotherapy alone or in combination with systemic 131I-MIBG. The records of patients with malignant paraganglioma who were treated with external beam radiotherapy at the University of Pennsylvania from February 1973 to February 2011 were reviewed in an institutional review board approved retrospective study. Of the 17 patients with tumors in the thorax, abdomen, or pelvis, 76% had local control or clinically significant symptomatic relief for at least 1 year or until death. As expected, the predominant toxicity was due to irradiation of tumor-adjacent normal tissues without clinically significant hematologic toxicity. Due to widespread systemic metastases with areas of bulky, symptomatic tumor, 5 of the 17 patients were treated with sequential 131I-MIBG (2 mCi/kg per treatment) and external beam radiotherapy to 9 sites. In these patients, all areas that were irradiated with external beam radiotherapy showed durable objective response despite all patients eventually experiencing out-of-field systemic progression requiring other treatment. Four of these patients remain alive with excellent performance status 16, 18, 23, and 24 months after external beam radiotherapy. External beam radiotherapy can be highly effective in local management of malignant paraganglioma and can be used in conjunction with 131I-MIBG due to nonoverlapping toxicities with excellent control of locally bulky tumors.     

Napromienianie dwa razy dziennie podwyższoną dawką frakcyjną chorych z przerzutami nowotworów złośliwych do mózgu. Wyniki końcowe prospektywnego badania klinicznego w nierandomizowanej grupie chorych

AimTo evaluate the morbidity and effectivness of twice a day hypofractionation in patients with brain metastases.Material / methodsBetween 1992 and 2000, 116 patients with brain metastases have been treated with whole brain radiotherapy alone and only in 33 patients radiotherapy was applied as adjuvant treatment after surgery. Radiotherapy was given in two of 3 Gy fractions daily with minimum 6 hours intervals between fractions to total dose of 39 Gy. Mean age of treated patients was 55 years. All patients were in general performance status evaluated according to the Karnofsky Performance Scale of at least 50.ResultsEarly tolerance of treatment was acceptable. Of 116 patients only 20 patients were treated with supportive treatment (anti-oedema drugs). Improvement of the neurological status was obtained in 26 patients (22%). The one-year overall survival was 21%. The one–year survival without clinical progression of disease was observed in 10% of all treated patients. Patients with solitary brain metastases treated with surgery and radiotherapy showed the best results.ConclusionsOur results showed that twice a day hypo-fractionation radiotherapy for patients with brain metastases is well tolerated and may provides benefit.     

The clinical effect study on malignant tumors with chronoradiotherapy

Like normal cells, tumor cells are also rhythmic. Chronochemotherapy has been proven to be effective in clinic, yet there are still some controversies about the efficacy and radiotherapy-related toxicity of chronoradiotherapy. This study was designed to investigate the therapy-related toxicity and short-term effect of four types of malignant tumor patients who were treated with radiotherapy at two different times. 121 cases of malignant tumor patients with radiotherapy indications were randomly divided into morning radiotherapy (MR) group and evening radiotherapy (ER) group, who received an identical procedure of radiotherapy at 9?am or 9 pm, respectively. The effects of radiotherapy were evaluated by short-term effect and therapy-related toxicity in this study. The efficacy rates of radiotherapy of lung cancer and nasopharyngeal carcinoma in ER groups were higher than those in MR groups, but the difference was not statistically significant (P > 0.05); the efficacy rates of radiotherapy of cervical and esophageal cancers in ER groups were significantly higher than those in MR groups (P < 0.05). The incidences of radiotherapy-related toxicity in these 4 types of malignant tumor patients were significantly lower in ER groups (P < 0.05), compared with MR groups. It suggests that irradiation in the evening could increase the efficacy in cervical and esophageal cancer patients and reduce the incidence of radiotherapy-related toxicity in these four malignant tumor patients.     

Electroacupuncture Prevents Cognitive Impairments by Regulating the Early Changes after Brain Irradiation in Rats

Cognitive impairments severely affect the quality of life of patients who undergo brain irradiation, and there are no effective preventive strategies. In this study, we examined the therapeutic potential of electroacupuncture (EA) administered immediately after brain irradiation in rats. We detected changes in cognitive function, neurogenesis, and synaptic density at different time points after irradiation, but found that EA could protect the blood-brain barrier (BBB), inhibit neuroinflammatory cytokine expression, upregulate angiogenic cytokine expression, and modulate the levels of neurotransmitter receptors and neuropeptides in the early phase. Moreover, EA protected spatial memory and recognition in the delayed phase. At the cellular/molecular level, the preventative effect of EA on cognitive dysfunction was not dependent on hippocampal neurogenesis; rather, it was related to synaptophysin expression. Our results suggest that EA applied immediately after brain irradiation can prevent cognitive impairments by protecting against the early changes induced by irradiation and may be a novel approach for preventing or ameliorating cognitive impairments in patients with brain tumors who require radiotherapy.     

EGFR突变与替莫唑胺联合IGRT大分割放射治疗非小细胞肺癌脑转移瘤疗效的相关性

摘要 目的：研究表皮生长因子受体（EGFR）突变对替莫唑胺联合图像引导大分割放射（IGRT）治疗非小细胞肺癌脑转移瘤临床疗效的影响。方法：选择2015年1月到2018年12月在我院接受治疗的非小细胞肺癌脑转移患者86例,根据是否出现EGFR突变分为对照组（EGFR未突变组）和研究组（EGFR突变组）,每组43人,两组患者均接受替莫唑胺联合IGRT大分割放射治疗。比较两组患者临床治疗疗效、不良反应发生情况、复发时间、生存时间和生活质量。结果：研究组患者临床治疗总有效率较对照组患者高（P<0.05）。研究组患者治疗后复发时间和生存时间均显著高于对照组患者（P<0.05）。两组患者治疗期间头痛、恶心、疲乏以及神经毒性等不良反应的发生情况比较无显著差异（P>0.05）。两组患者治疗前生活质量KarnofSky活动状态评分（KPS）和肺癌相关症状量表（LCSS评分）无显著差异（P>0.05）;治疗后,研究组患者KPS评分显著高于对照组（P<0.05）,而LCSS评分显著低于对照组患者（P<0.05）。结论：替莫唑胺联合IGRT大分割放射治疗EGFR突变的非小细胞肺癌脑转移瘤临床疗效更好,并且治疗后患者生活质量更优。     

Regionally Distinct Responses of Microglia and Glial Progenitor Cells to Whole Brain Irradiation in Adult and Aging Rats

Radiation therapy has proven efficacy for treating brain tumors and metastases. Higher doses and larger treatment fields increase the probability of eliminating neoplasms and preventing reoccurrence, but dose and field are limited by damage to normal tissues. Normal tissue injury is greatest during development and in populations of proliferating cells but also occurs in adults and older individuals and in non-proliferative cell populations. To better understand radiation-induced normal tissue injury and how it may be affected by aging, we exposed young adult, middle-aged, and old rats to 10 Gy of whole brain irradiation and assessed in gray- and white matter the responses of microglia, the primary cellular mediators of radiation-induced neuroinflammation, and oligodendrocyte precursor cells, the largest population of proliferating cells in the adult brain. We found that aging and/or irradiation caused only a few microglia to transition to the classically “activated” phenotype, e.g., enlarged cell body, few processes, and markers of phagocytosis, that is seen following more damaging neural insults. Microglial changes in response to aging and irradiation were relatively modest and three markers of reactivity - morphology, proliferation, and expression of the lysosomal marker CD68- were regulated largely independently within individual cells. Proliferation of oligodendrocyte precursors did not appear to be altered during normal aging but increased following irradiation. The impacts of irradiation and aging on both microglia and oligodendrocyte precursors were heterogeneous between white- and gray matter and among regions of gray matter, indicating that there are regional regulators of the neural response to brain irradiation. By several measures, the CA3 region of the hippocampus appeared to be differentially sensitive to effects of aging and irradiation. The changes assessed here likely contribute to injury following inflammatory challenges like brain irradiation and represent important end-points for analysis in studies of therapeutic strategies to protect patients from neural dysfunction.     

Whole brain radiotherapy: Consequences for personalized medicine

Several studies focusing on brain irradiation are in progress. Reflecting updates of relevant outcomes in palliative treatment of patients suffering from brain metastases, the primary objective of these studies is the evaluation of neurocognitive function and quality of life. Improvements of technology in radiation oncology allows us to spare the hippocampal region while appropriately irradiating other parts of brain tissue. Irradiation of the hippocampus region is likely to lead to manifestations of adverse events with a subsequent impact on patient''s quality of life, which is in fact an improper approach in palliative medicine. Ongoing studies evaluate results of hippocampus avoiding radiotherapy compared to standard whole brain radiotherapy. Incorporation of neurocognitive function assessment may result in the confirmation of superiority of sparing the region of hippocampus and thus change current style of providing brain irradiation.     

Multimodality Treatment May Improve the Survival Rate of Patients with Metastatic Nasopharyngeal Carcinoma with Good Performance Status

The aim of the present study was to evaluate the benefit of chemotherapy, combined with palliative radiotherapy (PRT) and other local treatments to the metastatic sites, for patients with metastatic nasopharyngeal carcinoma (NPC) who had a performance status 0–2. We conducted a retrospective review of available data from 197 biopsy-proven NPC patients who developed metastasis after their initial definitive treatment. These patients were grouped into three categories according to the different treatment paths that were followed: the best supportive care (64 patients), chemotherapy alone (55 patients), and multimodality treatment with chemotherapy combined with PRT and other local treatments to metastatic sites (78 patients). The 2-year metastatic survival rate of patients in the multimodality treatment group was 57.7%, which was significantly better than that of the patients in both the chemotherapy alone group and the best supportive care group (32.7% and 1.6%, respectively). The independent significant factors affecting survival were the disease-free interval prior to the detection of metastatic disease, the number of metastases, the number of chemotherapy cycles and the biological effective dose of PRT. In conclusion, multimodality treatment may improve survival of select patients with recurrent NPC with distant metastases.     

Hypofractionated radiotherapy for early breast cancer: Review of phase III studies

Breast-conserving surgery including whole breast irradiation has long been a recommended procedure for early breast cancer. However, conventionally fractionated radiotherapy requires a lengthy hospitalisation or prolonged commuting to a hospital for radiotherapy. In recent years, hypofractionated radiotherapy has increasingly been used. This method involves higher fraction doses (above 2 Gy) as compared to conventional radiotherapy, so the total dose can be delivered in fewer fractions and in a shorter overall treatment time. This review aims at presenting most important outcomes of four randomised studies comparing conventional and hypofractionated radiotherapy schemes including a total of 7000 patients. These studies have not shown apparent differences in treatment efficacy, incidence of late post-radiotherapy complications or cosmetic effects during a 5–10 year follow-up, but longer observation is warranted to fully evaluate the safety of this method. Currently, major societies consider modestly hypofractionated radiotherapy schemes as a routine management in selected groups of patients undergoing breast-conserving surgery. However, this method should be used cautiously in patients with lymph node metastases, big breasts, receiving chemotherapy or trastuzumab, or those under 50 years of age.     

放射加博宁治疗骨转移癌的病例分析

目的:观察放疗和博宁对骨转移癌的止痛效果。方法:对100例骨转移癌患者进行回顾性分析,单纯放疗30例,博宁加放疗14例,博宁加放化疗56例。结果:全组总有效率为89%,显效率达51%。各组有效率:单放组为83-3%,博宁加放疗组为92.9%,博宁加放化组为91.1%。三组间止痛效果无显著性差异(P>0.05)。在应用博宁治疗组中有一例出现类似过敏反应症状,其他无明显毒副反应发生。结论:放射治疗骨转移癌止痛迅速而有效。博宁治疗骨转移癌止痛效果明显,尤其适合应用于多发性骨转移癌患者。二者联合应用效果更加。     

Changes in circulating dendritic cells and IL-12 in relation to the angiogenic factor VEGF during IL-2 immunotherapy of metastatic renal cell cancer

Angiogenesis and immunosuppression are the main biological mechanisms responsible for cancer progression. Moreover, recent observations suggesting a negative influence of angiogenesis on anticancer immunity have shown that some angiogenic factors, such as VEGF, may induce immunosuppression. In addition, the evidence of abnormally high blood levels of VEGF has been proven to be associated with resistance to IL-2 immunotherapy. The present study was performed to establish a possible relation ship between the efficacy of IL-2 cancer immunotherapy and changes in circulating levels of VEGF, IL-12, mature and immature dendritic cells (DC). The study included 25 metastatic renal cell cancer patients who underwent subcutaneous low-dose IL-2 immunotherapy (6 MIU/day for 6 days/week for 4 weeks). Immature and mature DCs were identified as CD123+ and CD11c+ cells, respectively. The clinical response consisted of partial response (PR) in five, stable disease (SD) in 11 and progressive disease (PD) in the remaining nine patients. The mean IL-12 levels observed during IL-2 immunotherapy were significantly higher in patients with PR or SD than in those with PD, whereas the mean VEGF concentrations were significantly higher in patients who had PD than in those with PR or SD. Finally, a significant increase in the mean number of circulating mature DCs occurred only in patients with PR or SD, whereas no significant change was seen in patients with PD. By contrast, no significant change was observed in the mean number of immature DCs. This study shows that the efficacy of IL-2 immunotherapy is associated with a significant increase in circulating mature DCs and IL-12, without any concomitant increase in VEGF concentrations. Further studies will be required to better define the relationship between activation of anticancer immunity and control of angiogenesis-related mechanisms.     

Micronuclei in lymphocytes of young patients under antileukemic therapy.

The micronucleus test in peripheral blood lymphocytes was employed in the cytogenetic monitoring of children with acute lymphocytic leukemia (ALL), who had undergone chemotherapy and radiotherapy. Patients were treated with a variety of drugs, which included vincristine, methotrexate, daunomycin and prednisone; they also underwent cranial irradiation at the end of the first intensive phase of therapy. The first group under study consisted of 15 subjects on therapy, who showed a marked increase in micronucleated lymphocytes (mean: 19.96 +/- 12.96%) as a consequence of treatment compared with the control group (mean: 3.67 +/- 1.55%), while lower average values were obtained from 15 other subjects at the end of treatment (mean: 13.16 +/- 8.44%). A group of 6 patients was monitored during the entire period of therapy, namely at diagnosis, after 3 months of therapy, throughout maintenance therapy and at the end of it. The whole treatment lasted about 2 years. The results revealed a marked increase in basal micronucleus frequency, due to therapy: the micronucleated lymphocyte frequency remained significantly high throughout the treatment for almost all patients. These data clearly suggest the validity of the methodology in pointing out the role played by antileukemic agents in inducing somatic genetic damage.     

The role of radiotherapy in the prevention of recurrence and central nervous system metastases in childhood medulloblastoma

PURPOSE: To present the postoperative radiotherapy technique in children with medulloblastoma, and analyse the effectiveness of radiotherapy and the survival data. MATERIALS AND METHODS: 66 consecutive children (45 male and 21 female) received postoperative chemotherapy and radiotherapy between 1986 and 1998. The mean age was 8.3 years. The radiotherapy was performed with linear accelerator 9MV X-ray irradiation. The high risk patients received 36 Gy craniospinal irradiation, the low risk patients recived 30 Gy. The boost irradiation to the posterior fossa was 20 Gy in both patient groups. The patients received multi-drug chemotherapy immediately after the tumor resection. The radiotherapy started 6-8 weeks after the operation. RESULTS: All 66 patients were evaluated. The mean follow-up time was 45.4 months. The chance of cure is higher at age 8 or more, and less favorable under age 8. After 60 months 68.6% of children under age 8 and 75.9% older than 8 are alive. 20 children (64.5%) are alive after radical tumorectomy and 11 died. The 5 year overall survival was 71%. Recurrence was observed in 23/66 cases, it was the most frequent cause of death. Local failure was in posterior fossa in 15 patients (68.2%). CONCLUSION: The radicality of operation had no significant influence to the overall survival. The tumor stage, age of patients, risk group and metastases are important prognostic factors.