131I标记重组人表皮生长因子体内抑制乳腺癌生长的实验研究

研究 1 31 I标记重组人表皮生长因子 (1 31 I- Recombinant hum an epiderm al growth factor,1 31 I- rh EGF)对荷人乳腺癌裸鼠肿瘤生长的抑制作用。1 31 I- rh EGF在荷人乳腺癌裸鼠体内的组织分布实验证实 1 31 I- rh EGF的生物活性及乳腺癌组织对 1 31 I- rh EGF的摄取 ,通过给药后荷人乳腺癌裸鼠肿瘤的生长实验观察 1 31 I- rh EGF对肿瘤生长的影响 ,用透射电镜和病理组织学检查分别观察 1 31 I- rh EGF治疗后肿瘤细胞的超微结构变化和组织病理学变化。1 31 I-rh EGF的组织分布显示 ,荷人乳腺癌裸鼠的肿瘤组织对 1 31 I- rh EGF有明显摄取。肿瘤生长观察结果显示 ,静脉注射和瘤体内注射 1 31 I- rh EGF均能明显抑制肿瘤的生长 ,抑瘤率 (82 .0 0 %和 80 .70 % )显著大于 1 31 I(7.4 9% )和 1 31 I- HSA(6 .91% ) (P<0 .0 5 )。透射电镜和病理学观察均显示 ,静脉注射和瘤体内注射 1 31 I- rh EGF均能明显杀伤、杀死肿瘤组织细胞。实验表明 ,1 31 I- rh EGF能抑制裸鼠体内的人乳腺癌细胞生长 ,可望成为受体介导放射性靶向治疗乳腺癌的新药物     

microPET-CT显像监测叶酸受体靶向放射性药物药代动力学的实验研究

目的制备叶酸受体靶向的~(68)Ga-1,4,7,10-四氮杂环十二烷-1,4,7,10-四乙酸-赖氨酸-叶酸(~(68)Ga-DOTA-lysFA),用小动物正电子发射计算机体层摄影术(microPET)-CT动态显像考察其间质给药后体内药代动力学。方法合成~(68)Ga-DOTA-lys-FA,考察其理化特性。用人卵巢癌细胞(SKOV3)和人肺癌细胞(A549)测定受体结合实验。荷人卵巢癌细胞裸鼠模型33只,雌性,体质量18~20 g,鼠龄8~10周;瘤体直径0.6~0.8 cm;荷人肺癌细胞裸鼠模型4只,雌性,体质量18~20 g,鼠龄8~10周。通过尾静脉注射~(68)Ga-DOTA-lys-FA后不同时间点处死荷瘤鼠,解剖分离重要脏器称质量和用γ计数仪进行放射性测定,分析其体内生物学分布。抽签法随机分为~(68)Ga-DOTA-lys-FA尾静脉注射组(Ⅳ组)、肿瘤间质注射组(IT组),荷人肺癌细胞模型(A549)作为阴性对照组(ITC组),在给药后不同时间点行microPET-CT显像,勾画肿瘤及脏器感兴趣区并计算其放射性摄取(%ID和%ID/cm~3),对比分析~(68)Ga-DOTA-lys-FA给药后不同时间体内生物学分布。结果 ~(68)Ga-DOTA-lys-FA标记率为(97.80±2.11)%。3 h内体外稳定性好,尾静脉注射后microPET-CT获得的60 min肿瘤/肺部放射性摄取比值为5.36±1.03,明显高于生物学分布结果 (4.13±1.25,t=4.97,P=0.001)。基于microPET-CT定量,IT组60 min、180 min肿瘤放射摄取量分别为(125.60±18.40)%ID/cm~3、(91.80±14.50)%ID/cm~3,明显高于ITC组[(42.30±11.46)%ID/cm~3、(12.82±3.86)%ID/cm~3](P0.001、0.001),也明显高于IV组。结论 ~(68)Ga-DOTAlys-FA microPET-CT动态显像可更有效评价其体内生物学分布,瘤内注射可明显增加其瘤内生物半减期,为治疗性核素标记叶酸靶向治疗提供数据支持。     

冰片对MnTBAP透过大鼠血脑屏障的影响

目的探讨冰片对锰卟啉(MnTBAP)通过大鼠血脑屏障的影响。方法 SD大鼠分为对照组、131冰片组。对照组以75%乙醇灌胃,冰片组给予冰片0.7g/kg(75%乙醇溶解)灌胃,1h后尾静脉注射I-MnTBAP(1.85MBq/只),分别于注射后5、10、30、60、120、240、1440min取血液和脑脊液,用同位素示踪法测定大鼠血液和脑131-1脊液中I-MnTBAP的放射性计数,计算每克组织摄取注射剂量的百分率(%ID·g)。结果在给药后5¹440131-1 131min时间内,血液中I-MnTBAP的(%ID·g),冰片组和对照组相比无显著差异;而脑脊液中I-MnTBAP的-1(%ID·g),冰片组比对照组明显增加(<0.01)。结论冰片可促进MnTBAP透过血脑屏障,增加其在脑脊液中的浓度,而不改变其血药浓度。     

99Tcm标记抗PSMA单克隆抗体在荷瘤裸鼠体内的生物分布

目的研究99Tcm-抗前列腺特异性膜抗原(PSMA)抗体(J591)对前列腺癌细胞体外结合性能、在荷人前列腺癌裸鼠体内生物分布。方法用改进的Schwarz方法进行99Tcm标记,经Sephadex G-50柱分离纯化;用纸层析法和三氯醋酸法测定标记率与放化纯;用流式细胞术测定抗体与肿瘤细胞在体外的结合性能;PSMA阳性的C4-2前列腺癌裸鼠为实验组,PSMA阴性的PC3前列腺癌裸鼠为对照组,裸鼠静脉注射7.5 MBq(25μg/只)99Tcm-J591,分别于2、6、12及24h测定体内放射性分布,计算每克组织百分注射剂量率(%ID/g)及T/NT比值。结果表明99Tcm–J591标记率为(78.9±6.2)%,放化纯90%。J591与99Tcm–J591在体外能结合PSMA阳性的C4-2细胞,与PSMA阴性的PC3细胞不结合,显示出J591具有良好的特异性。生物分布实验显示:实验组裸鼠肿瘤部位出现99Tcm浓聚,对照组则没有。肿瘤组织百分注射剂量率(%ID/g)在12h达高峰,为(15.91±5.16)%ID/g,与对照组(3.22±1.33)%ID/g相比差异有统计学意义(P0.05),其余组织和器官的百分注射剂量率在两组间差异无统计学意义(P0.05)。结论 J591具有良好的免疫活性和对前列腺癌的靶向定位性能,可望用于前列腺癌的导向诊断及导向治疗。     

抗人黑色素瘤单克隆抗体在荷瘤裸鼠体内的分布及其定位显像

本文观察了~(131)I 标记的黑色素瘤 McAb HB8759在荷瘤裸鼠体内的生物学分布及放射免疫显像。静脉注射 ~(131)I—McAb48h 和72h 后肿瘤与非肿瘤在5种主要脏器比活性比值(T/NT)分别平均为6.6和9.6,~(131)I—McAb 注射24h 后在移植瘤中明显定位浓集,48～72h 是放射免疫显像的最佳时间。     

放射性碘标记特异性溶瘤重组腺病毒KH901在荷人肝癌裸鼠体内的抑瘤作用

研究131I标记的特异性溶瘤重组腺病毒KH901的生物活性及131I-KH901对荷人肝细胞肝癌裸鼠肿瘤的抑制作用。采用N-溴代琥珀酰亚胺(NBS)法用131I标记KH901,并采用ELISA法测定粒细胞-巨噬细胞集落刺激因子(GM-CSF)的生物活性;通过给药后荷人肝细胞肝癌裸鼠肿瘤的生长实验观察131I-KH901对肿瘤生长的影响,组织切片观察肿瘤组织形态学变化。结果显示:131I-KH901在肿瘤细胞中表达大量的GM-CSF因子,24 h后,在肿瘤细胞和正常细胞中产生的GM-CSF因子分别为183.27±6.90 pg/ml和20.44±0.77 pg/ml;肿瘤生长观察结果显示,131I-KH901瘤内给药能明显抑制肿瘤生长,抑瘤率为71.3%,显著大于131I组(22.7%)及KH901瘤内给药组(52.7%)(P<0.05),组织形态学观察示,注射131I-KH901后,肿瘤出现大片坏死区。因此,131I-KH901能明显抑制裸鼠体内人肝癌细胞的生长,可望成为腺病毒溶瘤和放射性核素联合治疗肿瘤的新型药物。     

荷淋巴瘤裸鼠放射免疫治疗99mTc-Annexin V凋亡显像的研究

探讨99mTc-Annexin Ⅴ凋亡显像在评价淋巴瘤131I-Rituximab放射免疫治疗疗效中的价值及其最佳显像时间。荷淋巴瘤裸鼠经肿瘤间质、尾静脉注射131I-Rituximab治疗后不同时间点进行99mTc-Annexin Ⅴ凋亡显像,并分离解剖肿瘤组织进行流式细胞术和免疫组织化学检查,根据其与凋亡显像的吻合程度确定显像最佳时间。结果显示：131I-Rituximab经肿瘤间质注射后24h、36h、48h、96h99mTc-Annexin Ⅴ凋亡显像肿瘤/非肿瘤组织摄取比（T/NT）分别为6.0±1.08、8.4±1.68、8.1±1.89、7.0±0.95,高于相同时间点静脉注射组（3.4±0.27、5.1±0.82、6.7±0.58、5.8±0.91）,且均与相同时间点细胞凋亡率、bax/bcl-2变化基本一致。结论：99mTc-Annexin Ⅴ凋亡显像作为无创性手段,能有效监测淋巴瘤131I-Rituximab放射免疫治疗后细胞凋亡情况,且放射免疫治疗后36h~48h是凋亡显像较佳时间。     

~(131)I标记单克隆抗体瘤内注射对结肠癌裸鼠移植瘤的放射免疫治疗

~(131)I标记抗结肠癌单克隆抗体CL3经两种途径给药治疗LS174t结肠癌细胞系裸鼠移植瘤。大剂量治疗组(18.5MBq/鼠)观察33d,瘤内和腹腔注射两种途径均具有明显的肿瘤抑制作用,与非治疗组、单纯CL3组和单纯~(131)I组有显著差异(P<0.05),两途径之间差距不大;瘤内注射两     

抗乳腺癌单克隆抗体放射免疫显像及治疗的实验研究

本实验用~(131)I标记HDI,用正常小鼠IgG(NMIgG)做对照,在荷人乳腺癌裸鼠模型上,进行组织分布、肿瘤定位显像和治疗的实验研究。结果表明,~(131)I-HDI对肿瘤有明显的特异性浓聚。注射后72、96h,     

HCV NS3 N端多肽诱导人肝细胞系转化及成瘤实验

目的 研究丙型肝炎病毒(HCV)非结构区3N端多肽(HCV NS3-5′)对人肝细胞株QSG7701的转化作用及致癌性。方法 通过脂质体介导将含有HCV NS3 N端cDNA的真核表达质粒(pRcHCNS3-5′)导入人源性肝细胞株QSG7701,G418筛选目的基因表达的细胞;聚合酶链反应(PCR)及免疫组织化学SP法检测细胞中HCV NS3基因及蛋白的表达;细胞计数,锚着非依赖性生长实验,成瘤性检测等鉴定其生物学行为变化,免疫组织化学S-P法检测所致肿瘤中HCV NS3及c-myc蛋白表达。结果 HCV NS3-5′转染的QSG7701细胞中NS3蛋白过度表达于胞质,质粒pRcHCNS3-5′转染细胞的倍增时间较pRcCMV转染细胞和未转染QSG7701细胞明显缩短(分别为12h,26h,28h)。pRcHCNS3-5′和pRcCMV转染细胞及未转染QSG7701在软琼脂中的克隆形成率分别为33.0％、1.5％、1.1％。pRcHCNS3-5′转染细胞的克隆率高于其他两种转染细胞(P<0.01)。三种细胞接种探鼠后,pRcHCNS3-5′转染细胞注射组出现肿瘤,为肝细胞癌,肿瘤组织有HCV NS3蛋白和c-myc蛋白的表达。阳性对照组亦出现肿瘤,而pRcCMV转染细胞及未转染QSG7701细胞注射组在注射40d后仍未见肿瘤发生。结论 HCV NS3 N端蛋白具有转化细胞和促进肿瘤发生的作用。     

Study of common functional genetic polymorphisms of FCGR2A, 3A and 3B genes and the risk for cryptococcosis in HIV-uninfected patients.

A pilot candidate gene association study was conducted to investigate the role of three common functional genetic polymorphisms of the low-affinity Fc gamma receptors, FCGR2A (131H/R), FCGR3A (158F/V) and FCGR3B (NA1/NA2) in Cryptococcus neoformans infections in individuals not infected with HIV. The FCGR2A 131RR and FCGR3A 158VV genotypes were over-represented [OR: 1.67 (1.05-2.63) and 2.04 (1.06-4.00), respectively] whereas the FCGR3B NA2NA2 was under-represented in patients with cryptococcosis (28% vs. 40% in controls). An analysis of haplotypes showed a significant difference in distribution between cases and controls overall and in Caucasians.     

Evaluation of human FcgammaRIIA (CD32) and FcgammaRIIIB (CD16) polymorphisms in Caucasians and African-Americans using salivary DNA

Two classes of low-affinity receptors for the Fc region of immunoglobulin G (IgG) (FcgammaR) are constitutively expressed on resting human neutrophils. These receptors, termed FcgammaRIIa (CD32) and FcgammaRIIIb (CD16), display biallelic polymorphisms which have functional consequences with respect to binding and/or ingestion of targets opsonized by human IgG subclass antibodies. The H131-R131 polymorphism of CD32 influences binding of human IgG2 and, to a lesser extent, human IgG3 to neutrophils. The neutrophil antigen (NA1-NA2) polymorphism of CD16 influences the efficiency of phagocytosis of bacteria opsonized by human IgG1 and IgG3. These polymorphisms may influence host susceptibility to certain infectious and/or autoimmune diseases, prompting interest in the development of facile methods for determination of CD32 and CD16 genotype in various clinical settings. We previously reported that genomic DNA from saliva is a suitable alternative to DNA from blood in PCR-based analyses of CD32 and CD16 polymorphisms. In the present study, we utilized for the first time this salivary DNA-based methodology to define CD32 and CD16 genotypes in 271 Caucasian and 118 African-American subjects and to investigate possible linkage disequilibrium between certain CD32 and CD16 genotypes in these two ethnic groups. H131 and R131 gene frequencies were 0.45 and 0.55, respectively, among Caucasians and 0.59 among African-Americans. NA1 and NA2 gene frequencies were 0.38 and 0.62 among Caucasians and 0. 39 and 0.61 among African-Americans. Since FcgammaRIIa and FcgammaRIIIb synergize in triggering neutrophils, we also assessed the frequency of different CD32 and CD16 genotype combinations in these two groups. In both groups, the R/R131-NA2/NA2 genotype combination was more common than the H/H131-NA1/NA1 combination (threefold for Caucasians versus sevenfold for African-Americans). Whether individuals with the combined R/R131-NA2/NA2 genotype are at greater risk for development of infectious and/or autoimmune diseases requires further investigation, which can be conveniently performed using DNA from saliva rather than blood.     

Fc gamma RIIa, IIIa and IIIb polymorphisms in Turkish children susceptible to recurrent infectious diseases

Abstract The efficacy of IgG-induced Fc gamma receptor (FcγR) function displays interindividual heterogeneity due to genetic polymorphisms of three FcγR subclasses: FcγRIIa, FcγRIIIa and FcγRIIIb. FcγR polymorphisms may contribute to disease susceptibility or may alter disease course. The aim of this study is to examine FcγR gene polymorphisms in Turkish children with recurrent respiratory tract infections and without well known humoral immunodeficiencies. For the patients in the study group (n=52), recurrent infection was defined as the presence of at least six infection episodes a year. Seventy-one healthy children with a maximum of two infections in a year were enrolled as the control group. Subjects in both groups had no abnormalities in serum immunoglobulins, IgG subsets and specific antibody levels. For FcγRIIa: H131H, H131R, R131R genotypes and 131R, 131H alleles; for FcγRIIIa: F158F, F158V, V158V genotypes and 158F, 158V alleles; and for FcγRIIIb: –NA1/NA1, NA1/NA2, NA2/NA2 genotypes and NA1, NA2 alleles were determined by using amplification refractory mutation system polymerase chain reaction (ARMS-PCR). Compared with the control group, the FcγRIIa-R131R genotype and 131R allele were found to be significantly elevated in the study group, and FcγRIIa-H131H genotype and 131H allele in the study group were significantly lower than in the control group. Genotypes and alleles related with FcγRIIIa and FcγRIIIb gene polymorphisms did not show any significant difference between the study and control groups. FcγRIIa gene polymorphism (R131R) may increase the risk and susceptibility for recurrent infectious diseases in children.     

131I标记重组人表皮生长因子在裸鼠体内的辐射生物学效应研究

研究131I标记的重组人表皮生长因子(131I-rhEGF)对荷人乳腺癌裸鼠的辐射生物学效应。通过131I-rhEGF在小鼠体内的分布实验找寻131I-rhEGF的主要浓聚组织,再通过生化检查和活组织病理检查检测131I-rhEGF对荷人乳腺癌裸鼠主要浓聚131I-rhEGF的组织的辐射损伤。131I-rhEGF在小鼠体内的分布实验显示,131I-rhEGF主要浓聚在肾、肝、脾、血。生化检查和活组织病理检查结果显示,注射131I-rhEGF2次(每次注射量相当于50kg人体注射14.58GBq,间隔为14d)对荷人乳腺癌裸鼠的肿瘤有较强的杀伤作用,而对肾、肝、脾和造血组织均无辐射损伤。因此,131I-rhEGF在受体介导放射性靶向治疗乳腺癌的过程中对正常组织是安全的药物。     

FcgammaRIIA, FcgammaRIIIA and FcgammaRIIIB polymorphisms in Spanish patients with systemic lupus erythematosus.

Linkage studies on human families suggest that receptors for the Fc fragments of immunoglobulin G (IgG) (FcgammaRs) could be implicated in the susceptibility to, or the progression of, some autoimmune diseases. In this work we analyse the possible role of polymorphic variants of FcgammaRIIA, FcgammaRIIIA and FcgammaRIIIB genes in the susceptibility to systemic lupus erythematosus, the prototype systemic autoimmune disease. A total of 276 Spanish patients (34 male and 242 female) with systemic lupus erythematosus were included in this cross-sectional study. The FcgammaRIIA-131, FcgammaRIIIA-176 and FcgammaRIIIB-NA1/NA2 polymorphisms were investigated in the patient group as well as in 194 ethnically matched controls using polymerase chain reaction-amplification refractory mutation system (PCR-ARMS). Statistical comparisons of genotype frequencies were performed using the chi2 test. In the case of the FcgammaRIIIB-NA1/NA2 polymorphism, an increase in the frequency of homozygous NA2/NA2 in patients was found (61.2 vs. 51.0%; P = 0.03; OR = 1.5; 95% CI = 1.03-2.24), as well as a decrease in the frequency of the NA1/NA2 genotype (28 vs. 38.7%; P = 0.02; OR = 0.6; 95% CI = 0.41-0.92). These associations were independent of patient gender and HLA-DRB1 specificities. With respect to the FcgammaRIIA-131 and FcgammaRIIIA-176 polymorphisms, no differences were found between patients and controls. Patient stratification according to their lupus-related nephritis status gave similar genotypic distribution patterns in both disease categories in all the cases.     

Association of Fcgamma receptor IIb and IIIb polymorphisms with susceptibility to systemic lupus erythematosus in Thais

We recently reported association of a newly identified polymorphism of Fcgamma receptor (FcgammaR) IIb, I232T, with systemic lupus erythematosus (SLE) in Japanese. To date, information on FcgammaR genotypes and their association with SLE is limited in South-east Asian populations. To gain further insight into the role of FcgammaR polymorphisms in the genetic predisposition of SLE, association of FcgammaRIIa-H131R, IIb-I232T, IIIa-F176V and IIIb-NA1/NA2 (HNA-1a/1b) polymorphisms with SLE was analyzed in the Thai population, using case-control association analysis. FcgammaRIIb-232T/T and IIIb-NA2/NA2 genotypes were associated with SLE with the odds ratio of 2.55. Genotype relative risk analysis revealed significant association of IIb-232T/T and IIIb-NA2/NA2, and a tendency of association of the IIIa-176F/F genotype. Moreover, carriers of FcgammaRIIa-131R were significantly increased in patients with lupus nephritis. Significant linkage disequilibrium was present among FcgammaRIIb, IIIa and IIIb, and two-locus analyses suggested that the tendency of association of FcgammaRIIIa could derive from linkage disequilibrium with IIb and IIIb. These results provided evidence that FcgammaR polymorphisms may be an important predisposing factor also in Thais in a complex manner.     

Association of rheumatoid factor production with FcgammaRIIIa polymorphism in Taiwanese rheumatoid arthritis

Fcgamma receptors (FcgammaR) impact upon the development of inflammatory arthritis through immune complex stimulation and proinflammatory cytokine production. FcgammaRIIa, FcgammaRIotaIotaIotaa and FcRgammaIIIb polymorphisms were genotyped in 212 rheumatoid arthritis (RA) patients and 371 healthy control subjects using an allelic-specific polymerase chain reaction (PCR). No significant skewing in the distribution of FcgammaRIIa H/R131, FcgammaRIIIa F/V158 and FcgammaRIIIb NA1/NA2 was found between RA patients and healthy control subjects. However, a significant skewing distribution of the FcgammaRIIIa F/V158 polymorphism was observed between rheumatoid factor (RF)-positive versus RF-negative RA patients (P = 0.01). The low-affinity FcgammaRIIIa F158 allele seems to have a protective role in RF production, in comparison with the FcgammaRIIIa V158 allele (P = 0.004; OR = 0.485; 95% CI: 0.293-0.803). A high frequency of FcgammaRIIIa F/F158 was identified in RA patients with negative RF compared with RF-positive patients (for FF158 versus FV158 + VV158; P = 0.002; OR = 0.372; 95% CI: 0.194-0.713). In addition, no association was found between FcgammaRIIa H/R131, FcgammaRhoIIIa F/V158 and FcgammaRIIIb NA1/NA2 polymorphisms and other clinical parameters. The results of this study suggest that three activating FcgammaRs polymorphisms lack association with RA but FcgammaIIIa F/V158 polymorphism may influence RF production and IgG RF immune complex handling in Taiwanese RA patients.     

Genetic risk factors for infection in patients with early rheumatoid arthritis

We analyzed clinical and genetic factors contributing to infections in 457 subjects with early rheumatoid arthritis (RA) enrolled in a prospective, 1-year clinical trial of methotrexate and the TNF inhibitor etanercept. Subjects were genotyped for the following single nucleotide polymorphisms (SNPs): (TNF -308, -238, and + 488); lymphotoxin-alpha (LTA) (LTA + 249, + 365, and + 720); and Fc gamma receptors FCGR2A 131 H/R; FCGR3A 176 F/V; and FCGR3B NA 1/2 and genotypes were correlated with infections. At least one URI was noted in 52% of subjects (99/191) with the NA2/NA2 genotype of the neutrophil-specific FCGR3B gene, compared to 42% (77/181) of those with the NA1/NA2 genotype and 39% (23/59) of those with the NA1/NA1 genotype (P = 0.038). Urinary tract infection (UTI) was associated with the TNF -238 A (odds ratio(OR) 2.56, 95% confidence interval (CI) 1.05-6.25) and LTA +365 C (OR 1.73, 95% CI 1.07-2.79) alleles, and marginally with the FCGR3A F allele (OR 1.72, 95% CI 0.99-3.00). There was a striking linear correlation between UTI and the number of risk alleles defined by these three SNPs (P < 0.001), suggesting an additive effect on susceptibility. These findings have important implications for the role of genetics in susceptibility to bacterial and viral infections.     

I-131-Lipiodol therapy in liver neoplasms

Twelve patients with liver neoplasms [10 HCC, 1 CCC, 1 multiple breast cancer metastases (BCM)] were treated by transarterial I-131-Lipiodol. Computed tomography (CT) and single photon emission CT (SPECT) showed pronounced I-131-Lipiodol accumulation in the tumor tissue in all cases. In three patients with HCC a reduction of tumor size was achieved after the first treatment. The remaining patients had big tumor masses; 5 of these (4 HCC, 1 CCC) had stable disease after the first treatment, and 2 HCC were progressive. One patient died immediately after therapy due to other reasons. The BCM proved significant reduction in number and size. Eighteen-FDG-PET (positron emission tomography with fluor-18-deoxy-glucose) and CT controls showed in part different results with pretherapeutic PET proving high interindividual variability in tumor activity. Side effects were tolerable. In summary, the therapy procedure with transarterial I-131-Lipiodol is safe and effective in tumors with moderate tumor mass.