Megavoltage external beam irradiation of craniopharyngiomas: analysis of tumor control and morbidity

From 1971 to 1985, 21 patients received megavoltage external beam radiation therapy at the University of Pittsburgh for control of craniopharyngioma. Minimum tumor doses prescribed to the 95% isodose volume ranged between 51.3 to 70.0 Gy. Median total dose was 60.00 Gy and median dose per fraction was 1.83 Gy. Three deaths occurred from intercurrent disease and no deaths from tumor progression. Actuarial overall survival was 89% and 82% at 5 and 10 years. Actuarial local control was 95% at 5 and 10 years. Radiation related complications included one patient with optic neuropathy, one with brain necrosis, and one that developed optic neuropathy followed by brain necrosis. The high dose group of patients who received a NSD or Neuret equivalent of greater than 60 Gy at 1.8 Gy per fraction had a significantly greater risk of radiation complications (p = .024). The actuarial risk at 5 years for optic neuropathy was 30% and brain necrosis was 12.5% in the high dose group. Tumor control in the high dose group was not shown to be significantly better. Any possible benefit in tumor control in treating patients with craniopharyngioma with doses above 60 Gy at 1.8 Gy per fraction appears to be offset by the increased risk of radiation injury.     

Neurocognitive effects of therapeutic irradiation for base of skull tumors

PURPOSE: To determine whether radiation therapy delivered to the paranasal sinuses causes any long-term impairment in neurocognitive function as a result of incidental brain irradiation. METHODS AND MATERIALS: Nineteen patients who received paranasal sinus irradiation at least 20 months and up to 20 years before assessment were given a battery of neuropsychologic tests of cognitive function. Radiation was delivered by a three-field (one anteroposterior and two lateral) technique. The median radiation dose was 60 Gy (range 50-68 Gy) in fractions of 1.8 to 2 Gy. The volume of irradiated brain was calculated from planning computed tomography slices or simulation films. The results of the neuropsychologic tests were compared to normative control values. RESULTS: Memory impairment was found in 80% of the patients, and one-third manifested difficulty with visual-motor speed, frontal lobe executive functions, and fine motor coordination. Two of the patients had frank brain necrosis with resultant dementia and blindness, and three had evidence of brain atrophy. Three of the fourteen patients without documented cerebral atrophy or necrosis were disabled from their normal activities. Three patients also developed pituitary dysfunction. Neurocognitive symptoms were related to the total dose of radiation delivered but not to the volume of brain irradiated, side of radiation boost, or chemotherapy treatment. The pattern of test findings was consistent with radiation injury to subcortical white matter. CONCLUSIONS: Radiation therapy for paranasal sinus cancer may cause delayed neurocognitive side effects. Currently, however, the development of severe adverse effects appears to be decreasing because of improvements in the techniques used to deliver radiation. Lowering the total dose and improving dose distributions should further decrease the incidence of delayed brain injury due to radiation.     

Development of a novel animal model to differentiate radiation necrosis from tumor recurrence

Distinguishing tumor progression from radiation necrosis after treatment in patients with brain tumors presents a clinical dilemma. A well-characterized, orthotopic rodent model of radiation-induced brain necrosis including a tumor is not currently available The objective of the study was to create focal radiation necrosis in rat brain bearing human glioblastoma (GBM) using stereotactic radiosurgery and confirm it by immuno-histological analysis. Nude rats implanted with primary GBM cells were irradiated using a stereotactic setup (n = 3) or received no radiation (n = 3). Ten weeks after the implantation, growth of the tumor was confirmed by magnetic resonance imaging (MRI). For each animal, MRI and contrast-enhanced CT images were obtained and fused using registration software. The tumor was identified and delineated using the fused CT/MR images. A treatment plan was generated using a 4 mm radiosurgery cone such that one portion of the tumor receives 100% dose of 60 Gy sufficient to cause necrosis, whereas the tumor edge at depth receives only 50% or less dose, allowing for regrowth of the tumor. The brains were collected 10 weeks after irradiation and immuno-histological analysis was performed. Hematoxylin and eosin staining showed central liquefaction necrosis in the high dose region consistent with necrosis and viable tumor in the peripheral low dose region. Ki-67 staining showed highly proliferative tumor cells surrounding the necrotic parts of the tumor. Luxol fast blue and lectin staining showed demyelination and vascular injury in brain tissue consistent with radiation necrosis. We have developed a novel model of radiation necrosis in rats bearing glioma.     

49例复发鼻咽癌的调强适形放射治疗

目的 评价调强适形放射治疗(IMRT)对复发性鼻咽癌的疗效、放射反应以及对肿瘤的控制。方法 49例鼻咽局部复发的鼻咽癌患者(KPS≥80)均采用全程IMRT,其中伴有颈淋巴结转移的3例患者(N12例,N3l例)在IMRT后,给予PDD 5-Fu方案5～6个疗程化疗。结果 治疗计划结果显示,覆盖鼻咽GTV D95的平均剂量为68．09Gy,GTV V95的平均体积为98．46％,靶区内GTV、CTV1和CTV2的平均剂量分别为71．40Gy、63．63Gy和59．81Gy。49例患者的中位随访时间为9个月(3～16个月)。局部无进展生存率100％,IMRT结束时有3例(6．1％)出现局部残留,14例(28．6％)出现鼻咽腔黏膜坏死。结论 IMRT能有利覆盖肿瘤靶区而使邻近敏感器官获得有效分隔,对复发性鼻咽癌的再程放疗不失为一种有效方法。值得注意的是高剂量的鼻咽局部IMRT治疗对于复发性鼻咽癌容易导致鼻咽黏膜坏死,故应适当减少GTV的处方剂量以60～65Gv为宜。     

Ewing's sarcoma: local tumor control and patterns of failure following limited-volume radiation therapy

Sixty children with localized osseous Ewing's sarcoma were treated between 1978 and 1988 with induction chemotherapy (cyclophosphamide, adriamycin), irradiation and/or surgery, and 10 months of maintenance chemotherapy (cyclophosphamide, adriamycin, dactinomycin, vincristine). Following induction chemotherapy, 43 patients received primary radiation therapy to limited radiation volumes defined by post-chemotherapy residual soft tissue tumor extension and initial osseous tumor extent. Irradiation was defined as low dose at 30-36 Gy (median 35 Gy) for 31 cases with objective response to induction chemotherapy and high dose at 50-60 Gy (median 50.4 Gy) for 12 patients with poor response to induction chemotherapy or with tumors greater than or equal to 8 cm. Overall event-free survival at 5 years is 59% and local tumor control is 68%. Initial failures have been local (12), simultaneous local and distant failures (7), and distant (6). In the surgical resection group, 14 patients had complete resection without radiation therapy, and 3 patients had microscopic residual plus 35-41 Gy; 100% local control has been maintained. In 43 patients with primary radiation therapy group, local tumor control is 58% (p = .004). Despite limited radiation volume, 18/19 local failures occurred centrally within the bone, well within the radiation volume. Imaging response to induction chemotherapy predicted local tumor control in the radiation therapy group: 62% with complete response/partial response versus 17% with no response/progressive disease (p less than 0.01). Local tumor control related strongly to primary tumor size in the radiation therapy group; among 31 cases receiving 35 Gy, local tumor control is 90% for lesions less than 8 cm versus 52% for tumors greater than or equal to 8 cm (p = .054). The central pattern of local failure in this experience suggests the effectiveness of limited radiation volume. The overall local tumor control rate following the tested dose level of 35 Gy appears to be inadequate, although results in selected cases with tumors less than 8 cm in greatest tumor dimension indicate potential efficacy in a yet limited experience.     

Impact of the time interval between surgery and postoperative radiation therapy on locoregional control in advanced head and neck cancer

Between January 1975 and December 1980, 111 patients with AJCC stages III and IV squamous cell carcinoma of the head and neck were treated with surgery followed by planned postoperative radiation therapy. A previous analysis of a subgroup of these patients showed that, when radiation was delayed more than 6 weeks from surgery, a higher incidence of regional failure occurred compared with the incidence observed when therapy began within a 6 week period. We have looked back at this group of patients plus others in an attempt to determine whether other factors played a role in the results obtained. In the current study, 50 patients had a delay of 6 weeks or more and, of these, 11 (22%) suffered a locoregional recurrence. However, 8 of these 11 patients received suboptimal radiation doses (less than 56 Gy) for permanent control of the disease. In fact, of 17 patients who received at least 60 Gy and had more than a 6 week delay, only 2 (12%) had locoregional failure. This was similar to the incidence of failure in the patients who received at least 60 Gy and who started radiation within the first 6 weeks from surgery (3/20 [15%]). The effect of delay was apparent only in those who received less than 60 Gy (27% vs. 7%, P less than 0.05). Therefore, we cannot validate the previous conclusion that a greater than 6 week delay in the delivery of postoperative radiation therapy in advanced head and neck cancers produces poorer results. The current analysis suggests that a prolonged delay in postoperative radiation therapy in itself does not have a negative impact on locoregional control as long as appropriate tumorcidal doses of more than 60 Gy are employed.     

Long-term radiation complications following conservative surgery (CS) and radiation therapy (RT) in patients with early stage breast cancer.

The frequency of brachial plexopathy, rib fracture, tissue necrosis, pericarditis, and second non-breast malignancies occurring in the treatment field among 1624 patients with early stage breast cancer treated with conservative surgery and radiation therapy at the Joint Center for Radiation Therapy between 1968 and 1985 is reported. The median follow-up time for survivors was 79 months (range 5-233 months). Brachial plexopathy was related to the use of a third field, the use of chemotherapy and the total dose to the axilla. Brachial plexopathy developed in 20 of 1117 women (1.8%) who received supraclavicular irradiation with or without axillary irradiation. The median time to its occurrence was 10.5 months (range 1.5-77 mo), and the majority (80%) of cases completely resolved. Among patients treated with a three-field technique, the incidence of brachial plexopathy was 1.3% (13/991) in patients treated with a dose to the axilla of less than or equal to 50 Gy, compared with 5.6% (7/126) in women treated with an axillary dose of greater than 50 Gy. The incidence of brachial plexopathy was 4.5% (15/330) among patients receiving chemotherapy, compared with 0.6% (5/787) when chemotherapy was not used (p less than 0.0001). Rib fracture was seen in 29 patients (1.8%), at a median time of 12 months following treatment (range 1-57). In all cases, the rib fracture healed without intervention. The incidence of rib fracture was 2.2% (28/1300) among patients treated on a 4 MV linear accelerator, compared with 0.4% (1/276) for patients treated on a 6 or 8 MV machine (p = 0.05). Of patients treated on a 4 MV machine, 0.4% (1/279) developed a rib fracture when a whole breast dose of 45 Gy or less was given, 1.4% (10/725) after receiving between 45 and 50 Gy, and 5.7% (17/296) following 50 Gy or higher. Tissue necrosis requiring surgical correction developed in three patients (0.18%) 22, 25, and 114 months after treatment. Presumed pericarditis (requiring hospitalization) was seen in 0.4% of women (3/831) who received radiation therapy to the left breast 2, 2, and 11 months after the start of treatment. Three women (0.18%) developed sarcomas in the treatments field at 72, 107, and 110 months, for a 10-year actuarial rate of 0.8%. Two of these sarcomas developed in areas of probable match-line overlap. One patient (0.06%) developed an in-field basal cell carcinoma at 42 months. In conclusion, the risk of significant complications following conservative surgery and radiation therapy for early stage breast cancer is low.(ABSTRACT TRUNCATED AT 400 WORDS)     

Effect of ionizing radiation on the human brain: white matter and gray matter T1 in pediatric brain tumor patients treated with conformal radiation therapy

OBJECTIVE: To test a hypothesis that fractionated radiation therapy (RT) to less than 60 Gy is associated with a dose-related change in the spin-lattice relaxation time (T1) of normal brain tissue, and that such changes are detectable by quantitative MRI (qMRI). METHODS: Each of 21 patients received a qMRI examination before treatment, and at several time points during and after RT. A map of brain T1 was calculated and segmented into white matter and gray matter at each time point. The RT isodose contours were then superimposed upon the T1 map, and changes in brain tissue T1 were analyzed as a function of radiation dose and time following treatment. We used a mixed-model analysis to analyze the longitudinal trend in brain T1 from the start of RT to 1 year later. Predictive factors evaluated included patient age and clinical variables, such as RT dose, time since treatment, and the use of an imaging contrast agent. RESULTS: In white matter (WM), a dose level of greater than 20 Gy was associated with a dose-dependent decrease in T1 over time, which became significant about 3 months following treatment. In gray matter (GM), there was no significant change in T1 over time, as a function of RT doses < 60 Gy. However, GM in close proximity to the tumor had an inherently lower T1 before therapy. Neither use of a contrast agent nor a combination of chemotherapy plus steroids had a significant effect on brain T1. CONCLUSION: Results suggest that T1 mapping may be sensitive to radiation-related changes in human brain tissue T1. WM T1 appears to be unaffected by RT at doses less than approximately 20 Gy; GM T1 does not change at doses less than 60 Gy. However, tumor appears to have an effect upon adjacent GM, even before treatment. Conformal RT may offer a substantial benefit to the patient, by minimizing the volume of normal brain exposed to greater than 20 Gy.     

Treatment of recurrent malignant gliomas with stereotactic intensity modulated radiation therapy

Malignant gliomas are usually refractory to aggressive combined-modality therapy, and the incidence of recurrence and death after treatment is very high. State-of-the-art techniques such as stereotactic intensity-modulated radiation therapy (IMRT) are now available to deliver a high dose of radiation to the tumor with relative preservation of surrounding tissues to achieve optimal tumor coverage with minimal toxicity. We report 10 patients (median age 48 years) with recurrent malignant gliomas that were treated with stereotactic directed IMRT. Initial tumor histologies included one low grade glioma (upgraded to anaplastic astrocytoma at recurrence), four anaplastic astrocytomas, and four glioblastomas multiforme. One patient was originally presumed to have a brain metastasis secondary to renal cell carcinoma but was pathologically confirmed as having glioblastoma multiforme at the time of recurrence. Before recurrence, all patients had been treated with external beam radiation therapy (median 59.7 Gy). All recurrences were confirmed by a subtotal resection (5/10) or by imaging (5/10). The median Karnofsky performance score at the time of IMRT was 80. The median tumor volume was 34.69 cm. Treatment was delivered on a 10-MV linear accelerator with a mini-multileaf collimator, MIMiC, and planned with Peacock/Corvus software. Radiation was delivered in daily fractions of 5 Gy, to a total median dose of 30 Gy at the 71% to 93% median isodose line. Median overall survival time was 10.1 months from the date of stereotactic treatment, with 1- and 2-year survival rates of 50% and 33.3%, respectively. Fractionated stereotactic intensity modulated radiation therapy is a novel technique used in the treatment of recurrent malignant gliomas, which produces results comparable to other currently used stereotactic techniques.     

Cerebral radiation necrosis: incidence, outcomes, and risk factors with emphasis on radiation parameters and chemotherapy

PURPOSE: To investigate radiation necrosis in patients treated for glioma in terms of incidence, outcomes, predictive and prognostic factors. METHODS AND MATERIALS: Records were reviewed for 426 patients followed up until death or for at least 3 years. Logistic regression analysis was performed to identify predictive and prognostic factors. Multivariate survival analysis was conducted using Cox proportional hazards regression. Separate analyses were performed for the subset of 352 patients who received a biologically effective dose (BED) > or =85.5 Gy2 (> or =45 Gy/25 fractions) who were at highest risk for radionecrosis. RESULTS: Twenty-one patients developed radionecrosis (4.9%). Actuarial incidence plateaued at 13.3% after 3 years. In the high-risk subset, radiation parameters confirmed as risk factors included total dose (p < 0.001), BED (p < 0.005), neuret (p < 0.001), fraction size (p = 0.028), and the product of total dose and fraction size (p = 0.001). No patient receiving a BED <96 Gy2 developed radionecrosis. Subsequent chemotherapy significantly increased the risk of cerebral necrosis (p = 0.001) even when adjusted for BED (odds ratio [OR], 5.8; 95% confidence interval [CI], 1.6-20.3) or length of follow-up (OR, 5.4; 95% CI, 1.5-19.3). Concurrent use of valproate appeared to delay the onset of necrosis (p = 0.013). The development of radionecrosis did not affect survival (p = 0.09). CONCLUSIONS: Cerebral necrosis is unlikely at doses below 50 Gy in 25 fractions. The risk increases significantly with increasing radiation dose, fraction size, and the subsequent administration of chemotherapy.     

130例脑转移瘤常规放疗和调强放疗的疗效分析

目的 评价调强放射治疗在脑转移瘤治疗中的疗效.方法 将130例脑转移瘤患者随机分成常规放疗组和调强放射治疗组.常规放疗组64例,先行全脑放射治疗(WBRT)36～40 Gy后,局部缩野加量,总剂量到50～60 Gy,每次2 Gy,5次/周.调强放射治疗组66例,全脑放射治疗剂量39.2～39.6Gy,脑转移灶剂量54～60 Gy,5次周,共23次.结果 治疗结束后3月、6月复查,对1～3个脑转移灶患者,常规放疗组和调强放疗组的中位生存期、有效率(CR+ PR)和1年生存率分别为13月、82％、59％和14月、88％、61％.对于脑转移灶数目大于3个的患者,常规放疗组和调强放疗组的中位生存期、有效率(CR+ PR)和1年生存率分别为9月、73％、47％和13月、87.5％、59％.结论 调强放射治疗可能是多发脑转移瘤患者的一种较常规全脑放疗更有效的治疗手段.     

FDG PET-CT标准摄取值在预测放射性肺炎发生中的作用

目的 探讨肺癌患者放射治疗前后FDG PET-CT标准摄取值(SUV)及其变化在预测放射性肺炎发生中的作用.方法 40例未经手术的非小细胞肺癌(NSCLC)患者在放射治疗前后均行PET-CT检查,分别测量出受照≤5 Gy、5.1～15 Gy、15.1～35 Gy、35.1～60 Gy以及>60 Gy肺组织放射治疗前后的平均SUV,比较发生放射性肺炎组与未发生放射性肺炎组SUV的变化情况,以及受照肺组织的SUV与未受照射肺组织SUV值之比(L/B).结果 40例患者中,有8例在治疗后发生放射性肺炎,其中2级6例,3级2例.受照剂量35.1～60 Gy肺组织的SUV与放射性肺炎的发生明显相关,当SUV≥1时,放射性肺炎的发生率为41.7%,明显高于全组放射性肺炎的发生率(20.0%;X2=3.96,P<0.05),SUV预测放射性肺炎的敏感度和特异度分别为62.5%和78.1%.L/B≥2.5时,放射性肺炎的发生率为40.7%,亦明显高于全组放射性肺炎的发生率(20.0%;X2=4.92,P<0.05).以L/B≥2.5为标准预测放射性肺炎的敏感度和特异度分别为72.7%和90.9%.SUV≥1与L/B≥2.5在预测放射性肺炎发生率之间的差异无统计学意义(X2=0.002,P>0.05).结论 SUV和L/B的大小与放射性肺炎的发生呈正相关,临床医生可根据FDG PET-CT提供的SUV和L/B来预测放射性肺炎的发生.     

Dose-response for local control with hyperfractionated radiation therapy in advanced carcinomas of the upper aerodigestive tracts: preliminary report of radiation therapy oncology group protocol 83-13

A prospective, randomized Phase Ilate/II trial of hyperfractionated radiation therapy was conducted: 1.2 Gy minimum tumor dose was administered twice daily with a minimum interval of 4 hr, 5 days per week. Patients with Stage III and IV carcinomas of the oral cavity, oropharynx, nasopharynx, hypopharynx, and supraglottic larynx were stratified by site, presence or absence of nodal metastases, and performance status. They were assigned to four total doses between 67.2 Gy and 81.6 Gy to all known tumors. The highest dose arm was opened after preliminary assessment indicated acceptable late morbidity rates with the three lower doses. Of 479 patients entered, 260 patients were randomized to the three lower total doses and 237 were analyzed for this preliminary report: 63 were assigned to receive 67.2 Gy, 58 to 72.0 Gy, and 116 to 76.8 Gy. Estimates of grade 4 necrosis at 2 years were 10.0%, 5.1%, and 13.9%, respectively, for patients who received total doses of 67.2 Gy, 72.0 Gy, and 76.8 Gy. There was a suggestion of a trend toward increased local control at 24 months (Kaplan-Meier estimates of 25% for 67.2 Gy, 37% for 72.0 Gy, and 42% for 76.8 Gy) (p = .08). No difference was observed in survival. Assessment of the results using Cox regression models to correct for slight inequalities of pretreatment prognostic variables supported a total dose-tumor control relationship (p = .054). Results for the lowest dose arm were comparable to previous RTOG studies of common fractionation with similar total doses. The higher local control rates with 72.0 and 76.8 Gy using hyperfractionated radiation therapy suggest an improvement in outcome with radiation therapy for advanced carcinomas of the upper aerodigestive tracts. These preliminary findings have led to a Phase III comparison of hyperfractionated radiation therapy with 1.2 Gy b.i.d. with standard fractionation.     

Acute radiation-induced pulmonary damage: a clinical study on the response to fractionated radiation therapy

Acute radiation-induced pulmonary damage can be a significant cause of morbidity in radiation therapy of the thorax. A prospective, clinical study was conducted to obtain dose-response data on acute pulmonary damage caused by fractionated radiation therapy. The endpoint was a visible increase in lung density within the irradiated volume on a computed tomographic (CT) examination as observed independently by three diagnostic radiologists. Fifty-four patients with various malignancies of the thorax completed the study. CT chest scans were taken before and at preselected times following radiotherapy. To represent different fractionation schedules of equivalent biological effect, the estimated single dose (ED) model, ED = D X N-0.377 X T-0.058 was used in which D was the average lung dose within the high dose region in cGy, N was the number of fractions, and T was the overall treatment time in days. Patients were grouped according to ED and the percent incidence of pulmonary damage for each group was determined. Total average lung doses ranged from 29.8 Gy to 53.6 Gy given in 10 to 30 fractions over a range of 12 to 60 days. Five patient groups with incidence ranging from 30% (ED of 930) to 90% (ED of 1150) were obtained. The resulting dose-response curve predicted a 50% incidence level at an ED value (ED50) of 1000 +/- 40 ED units. This value represents fractionation schedules equivalent to a total average lung dose of 32.9 Gy given in 15 fractions over 19 days. Over the linear portion of the dose-response curve, a 5% increase in ED (or total dose if N and T remain constant), predicts a 12% increase in the incidence of acute radiation-induced pulmonary damage.     

Clinical dose-volume histogram analysis in predicting radiation pneumonitis in Hodgkin's lymphoma

PURPOSE: To quantify the incidence of radiation pneumonitis (RP) in a modern Hodgkin's lymphoma (HL) cohort, and to identify any clinically relevant parameters that may influence the risk of RP. METHODS AND MATERIALS: Between January 2003 and February 2005, 64 consecutive HL patients aged 18 years or older receiving radical mediastinal radiation therapy (RT) were retrospectively reviewed. Symptomatic cases of radiation pneumonitis were identified. Dose-volume histogram parameters, including V(13), V(20), V(30), and mean lung dose (MLD), were quantified. RESULTS: At a median follow-up of 2.1 years, the actuarial survival for all patients was 91% at 3 years. There were 2 (2/64) cases of Radiation Therapy Oncology Group (RTOG) Grade 2 RP (incidence 3.1%). Both index cases with corresponding V(20) values of 47.0% and 40.7% were located in the upper quartile (2/16 cases), defined by a V(20) value of > or =36%, an incidence of 12.5% (p = 0.03). Similarly for total MLD, both index cases with values of 17.6 Gy and 16.4 Gy, respectively, were located in the upper quartile defined by MLD > or =14.2 Gy, an incidence of 11.8% (2/17 cases, p = 0.02). CONCLUSIONS: Despite relatively high V(20) values in this study of HL patients, the incidence of RP was only 3%, lower compared with the lung cancer literature. We suggest the following clinically relevant parameters be considered in treatment plan assessment: a V(20) greater than 36% and an MLD greater than 14 Gy, over and above which the risk of RTOG Grade 2 or greater RP would be considered clinically significant.     

Once-a-week vs conventional daily radiation treatment for lung cancer: final report

This is the final report of a prospective randomized clinical trial which began in 1982 and explored once-a-week hypofractionation in lung cancer patients with unresectable, non-metastatic, measurable, loco-regionally advanced disease. Stratification to this protocol has been done by histology, stage, and performance status categories. Patients with ipsilateral supraclavicular and/or brain metastases as the only evidence of distant spread, have been included in the study, but were stratified and analyzed separately. The two protocol arms were: (I) Conventional daily radiation [5 x W]-5 daily fractions of 2 Gy each to a total dose of 60 Gy in 6 weeks, protecting the spinal (SC) at 45 Gy and (II) Once-a-week radiation [1 x W]-one weekly fraction of 5 Gy each to a total tumor dose of 60 Gy in 12 weeks protecting the SC at 30 Gy. A total of 150 patients have been entered. Of these, 30 pts. are inevaluable, but the reasons of non-compliance, progression of disease or death due to intercurrent disease were of equal incidence in both groups. Of the 120 evaluable patients, 63 were treated 5 x W and 57 with 1 x W therapy. Complete tumor responses are similar in both arms with 1 x W pts demonstrating a numerical advantage (26% vs 17%). The average follow-up of the entire series is 3 yrs with a range of 12-66 months. Survival data is comparable in both groups with the 12 and 24 month actuarial survival of 49% and 23% for the 5 x W arm and 59% and 29% for the 1 x W arm. 1 x W patients continue to show a better tolerance than 5 x W pts. There are sufficient long-term survivors in both arms to assess chronic toxicity. The number of patients alive at 12, 18, and 24 months were 25, 11, and 5 for the 5 x W arm and 29, 16, and 7 for the 1 x W arm. No significant differences in late reactions have been noted. The longest surviving patient in the 1 x W arm is now 48 months after treatment.     

造血干细胞移植前全身照射急性放射性反应与照射剂量的关系

目的探讨造血干细胞移植前全身照射急性放射性反应与照射不同总剂量及分次剂量的关系。方法回顾性分析2015年5月至2019年12月于石家庄平安医院造血干细胞移植前接受6 MV X线全身照射预处理的48例患者的临床资料。将患者按照射总剂量分为8 Gy组(12例)、10 Gy组(31例)和12 Gy组(5例),按分次照射剂量分为4 Gy/次组(17例)和5 Gy/次组(31例),总结比较各组患者放疗后的口腔黏膜、咽部、涎腺、上消化道、下消化道及肺的急性放射性反应发生情况。结果照射总剂量8 Gy组咽部急性放射性反应0级11例(91.7%),1级1例(8.3%);10 Gy组0级10例(32.3%),1级13例(41.9%),2级4例(12.9%),3级3例(9.7%),4级1例(3.2%);12 Gy组0级2例(40.0%),1级、2级、3级各1例(20.0%);照射总剂量8 Gy组咽部急性放射性反应较10 Gy组和12 Gy组轻,差异有统计学意义(χ2=11.338,P=0.003);其他部位急性放射性反应发生率差异均无统计学意义(均P>0.05)。分次照射剂量4 Gy/次组咽部急性放射性反应0级13例(76.5%),1级2例(11.8%),2级、3级各1例(5.9%);5 Gy/次组0级10例(32.3%),1级13例(41.9%),2级4例(12.9%),3级3例(9.7%),4级1例(3.2%);分次照射剂量4 Gy/次组咽部急性放射性反应较5 Gy/次组轻,差异有统计学意义(Z=-2.606,P=0.009);其他部位急性放射性反应发生率差异均无统计学意义(均P>0.05)。结论造血干细胞移植前全身照射总剂量8 Gy及分次剂量4 Gy/次能减轻咽部急性放射性反应。     

Preoperative radiation therapy with selective dose escalation to the margin at risk for retroperitoneal sarcoma

BACKGROUND: Retroperitoneal sarcomas (RPSs) are rare tumors with poor survival rates due to difficult resectability and high local and distant recurrence rates. Preoperative radiation therapy appears to have dosimetric advantages to utilize the tumor as a tissue expander to limit exposure of small bowel to higher radiation doses. METHODS: Between June 1999 and December 2003, 16 consecutive patients with biopsy-proven RPS were treated with preoperative radiation with selective dose escalation. This included 45 grays (Gy) in 25 fractions to the entire tumor plus margin and a boost dose of 57.5 Gy to the volume predicted as high risk for positive surgical margins. Treatment toxicity and local control were evaluated prospectively as primary endpoints. The secondary goal was the theoretical calculation of future dose escalation and feasibility. Each patient underwent laparotomy. Tumor response was judged using computed tomography (CT) scan and by necrosis on final pathology. Theoretical treatment plans evaluated the potential for additional radiation dose escalation. RESULTS: All patients completed the radiation protocol. The most common acute side effects were nausea/vomiting, which affected 4 patients (25%), with only 1 patient requiring inpatient intravenous hydration. There was no severe late postoperative morbidity or mortality. Twelve tumors (75%) decreased in maximum dimension, with a median decrease of 9.4%. Fourteen of 16 patients (88%) underwent complete macroscopic resection. With a median follow-up of 28 months (range, 7-52 months), there were only 2 local recurrences. The actuarial 2-year local control rate was 80%. Theoretical treatment plans suggest that significant dose escalation (up to 80 Gy) may be possible. CONCLUSIONS: Preoperative radiation therapy with selective dose escalation to the margin at risk is tolerable and allows higher radiation dose to the volume judged to be at greatest risk for local tumor recurrence.     

Role of radiation therapy and radiosurgery in glioblastoma multiforme

Randomized trials have supported a role for radiation therapy in the initial management of Glioblastoma Multiforme (GBM) for over twenty-five years. Although technological advances in imaging and three-dimensional treatment planning have reduced the toxicity for patients and have allowed safe radiation dose escalation, unfortunately they have not produced a correspondingly dramatic improvement in overall survival. The dose of 60 Gy partial brain RT remains the standard of care for patients with newly diagnosed GBM. Recently completed randomized trials of brachytherapy and radiosurgery do not support these modalities in the initial management of GBM, but these and other focal RT techniques such as intensity modulated radiation therapy enable safe retreatment in selected patients. Future studies will need to explore radiation biologic response modification and radiosensitization through targeted therapies.