人胃腺癌组织的自体荧光光谱特性

目的:探讨人胃腺癌组织的自体荧光光谱特性.方法:测定26例胃腺癌标本肿瘤及非肿瘤区域的组织自体荧光光谱.结果:人胃腺癌组织自体荧光光谱与非肿瘤胃壁组织自体荧光光谱明显不同,人胃腺癌组织自体荧光光谱的峰值明显低于非肿瘤胃壁组织;用波长为360nm、390nm激光激发的人胃腺癌组织自体荧光光谱出现双峰.结论:用激光激发的自体荧光光谱可有效识别人胃腺癌组织与非肿瘤胃壁组织.     

人胃腺癌组织的自体荧光光谱特性

目的：探讨人胃腺癌组织的自体荧光光谱特性。方法：测定26例胃腺癌标本肿瘤及非肿瘤区域的组织自体荧光光谱。结果：人胃腺癌组织自体荧光光谱与非肿瘤胃壁组织自体荧光光谱明显不同，人胃腺癌组织自体荧光光谱的峰值明显低于非肿瘤胃壁组织；用波长为360nm、390nm激光激发的人胃腺癌组织自体荧光光谱出现双峰。结论：用激光激发的自体荧光光谱可有效识别人胃腺癌组织与非肿瘤胃壁组织。     

利用组织芯片技术检测硒蛋白P在胃癌组织中的表达

目的:研究胃腺癌组织芯片中硒蛋白P的表达。方法:选用胃腺癌组织30例制备组织芯片,30例正常胃组织作为对照,用免疫组化的方法观察硒蛋白P在胃腺癌组织中的表达。结果:硒蛋白P在胃腺癌组织中的表达(17/30,56·7%)低于在正常胃组织中的表达(25/30,83·3%),二者差异有统计学意义,P=0·030;硒蛋白P在高、中分化病例中的阳性表达率为76·5%(13/17),高于低分化病例中表达率30·8%(4/13),二者差异有统计学意义,P=0·004;硒蛋白P在Ⅰ~Ⅱ期病例中表达为57·9%(11/19),Ⅲ期病例中表达为54·5%(6/11),二者差异无统计学意义,P=0·672。结论:硒蛋白P在胃腺癌组织中为低表达,与肿瘤的分化程度呈负相关,与肿瘤的TNM分期无关。     

KiSS-1基因和基质金属蛋白酶-9在妊娠滋养细胞疾病组织中的表达及其意义

目的探讨浸润相关基因KiSS-1和基质金属蛋白酶-9(matrix metalloproteinase,MMP-9)在妊娠滋养细胞疾病中的表达。方法用RT-PCR和Western blot法检测30例正常早期妊娠绒毛、30例葡萄胎、9例侵蚀性葡萄胎和8例绒毛膜癌中KiSS-1和MMP-9mRNA及其蛋白的表达。结果正常妊娠早期绒毛、葡萄胎和侵蚀性葡萄胎组织中均有MMP-9和KiSS-1表达,而在绒毛膜癌组织中仅有MMP-9基因和蛋白的表达,无KiSS-1基因和其蛋白肽metas-tin的表达。妊娠滋养细胞疾病组织[包括葡萄胎、侵蚀性葡萄胎及绒毛膜癌]中MMP-9的基因和蛋白表达均显著高于早期妊娠绒毛组织(P=0·039、0·001、0·000),其中侵蚀性葡萄胎及绒毛膜癌组织中显著高于葡萄胎(P=0·000),绒毛膜癌中MMP-9基因表达水平最高(分别为0·705±0·141和78·403±7·124)。而KiSS-1基因的表达正相反葡萄胎组织的KiSS-1mRNA(0·433±0·193)和metastin表达(23·831±7·522)显著低于早期妊娠绒毛组织(P=0·049、0·049),侵蚀性葡萄胎组织中KiSS-1mRNA和metastin表达水平更低(分别为0·113±0·121和10·814±3·431)。结论促浸润基因MMP-9的表达变化与滋养细胞浸润活性呈正相关,而抑浸润基因KiSS-1的表达变化则与滋养细胞浸润活性呈负相关。这两种基因相互作用在滋养细胞浸润活性调控中起重要作用。     

血卟啉单甲醚激光诱发荧光光谱区分肺癌组织和正常支气管组织

目的　探讨应用国产新型光敏剂血卟啉单甲醚 (HMME)激光诱发荧光光谱分析方法诊断肺癌的可行性。方法　 15例肺癌患者肺切除前 3小时静脉注射HMME 2 .5mg/kg ,使用三倍频YAG激光 (波长 35 5nm)和光学多道分析仪 (OMA)对切除的癌组织和正常支气管组织行激光诱发荧光光谱测定。 43个检测点均行病理检查。结果　 15例患者术后 48小时后接受阳光照射 ,无一例发生皮肤光过敏副作用。肺癌组织的荧光强度 ( 314 4 6± 5 0 17)显著低于正常支气管组织 ( 75 430± 890 8) (P <0 .0 0 1)。正常支气管组织光谱在长波区5 80～ 6 0 0nm处有一个小坪 (I580nm/I6 0 0nm =1.0 81± 0 .0 90 ) ,而肺癌组织则平滑下降 (I580nm/I6 0 0nm=1.2 6 0± 0 .15 7)。肺癌组织于 6 2 3 .4nm± 1.6nm处有一明显的特征峰 (即药物峰 )。以I580nm/I6 0 0nm比值为判据 ,诊断肺癌的敏感性、特异性和符合率分别为 80 .0 %、73 .9%和 76 .7% ;以药物峰斜率为判据 ,诊断肺癌的敏感性、特异性和诊断符合率分别为 95 .0 %、91.3 %和 93 .0 %。结论　新型光敏剂血卟啉单甲醚 (HMME)激光诱发荧光光谱能够区分肺癌和正常支气管组织 ,与激光诱发自体荧光相比 ,能够提高诊断肺癌的敏感性、特异性和符合率     

贲门癌FasL上调与肿瘤浸润性淋巴细胞凋亡

目的 :探讨老年贲门癌FasL表达上调与肿瘤浸润性淋巴细胞 (TIL)凋亡的关系。方法 :采用免疫组织化学S P法 ,检测 5 0例老年贲门癌组织中FasL表达及TIL的数量。采用脱氧核糖核酸末端转移酶介导的缺口末端标记技术 (TUNEL) ,对其中 4 0例贲门癌组织中凋亡的TIL及肿瘤细胞进行观察。结果 :5 0例贲门癌组织FasL蛋白表达程度不等。FasL表达程度高的组织TIL计数低于FasL表达低的组织 ,同时其TIL凋亡指数高于FasL表达低的组织 ,P <0 0 5 ;而贲门癌细胞的凋亡指数低于FasL表达程度低的组织 ,P <0 0 1;TIL凋亡指数与贲门癌细胞的凋亡指数呈负相关 ,γ =- 0 5 1,P <0 0 1。结论 :老年贲门腺癌有不同程度的FasL表达 ,其表达程度与TIL的浸润程度和凋亡相关 ,可能是老年贲门癌免疫逃逸的重要机制之一。     

河南贲门癌高发区癌组织浸润淋巴细胞CD4和CD8及δγT的表达及意义

目的:探讨河南高发区贲门癌组织浸润淋巴细胞CD4、CD8和δγT的表达变化特征及其意义。方法:采用ABC和组织病理学方法,分析20例贲门癌组织和20例正常贲门对照组淋巴细胞CD4、CD8和δγT的表达状况。结果:贲门癌组织比正常组织CD8(68·05±29·85vs51·85±18·20,P=0·045)和δγT免疫阳性细胞数(7·50±4·24vs4·90±2·65,P=0·025)升高;贲门癌组织CD4免疫阳性细胞数比正常组织降低(68·35±28·73vs89·75±35·34,P=0·042);但是,正常组织CD4 /CD8 细胞比值明显高于贲门癌组织(1·88±0·76vs1·01±0·06,P=0·000)。结论:贲门癌患者免疫功能异常,可能与贲门癌变有关。     

保留迷走神经加胃底重建预防食管贲门癌术后胃食管返流的研究

目的:通过测定保留迷走神经加胃底重建术后胃和食管的功能变化,探讨减少食管、贲门癌切除术后反流性食管炎的方法。方法: 对 68 例无外侵食管、贲门癌患者施行根治性切除,术中保留迷走神经加胃底重建,通过患者的自觉症状、上消化道压力、胃镜等多项指标对患者手术前后进行定量观察。结果:与切断组患者相比,保留组患者术后嗳气、返流、烧心、吞咽疼痛等症状明显改善,P= 0 001;术后 1 年体质量(62 .9±4 .4) kg,与术前(62 5±4. 3) kg比较,差异无统计学意义,P=0. 579;反流性食管炎的发生率为 20 .58%(14/68),低于切断组80 .88%(55/68)且程度较轻,P=0 002;术后1个月及1年食管体部静息压分别为(1. 59±1. 28)kPa及(1. 43±1. 15) kPa,显著高于正常人食管体部静息压(0. 26±0 .68) kPa和胃静息压(0 .57±0. 43) kPa,P=0 .001;术后1个月及1年的食管体部收缩压分别为(5. 73±3. 65) kPa及(5. 17±2. 11)kPa,高于切断组术后1个月及1年的收缩压(3. 51±2. 61) kPa及(3. 21±2 .46)kPa,P=0 .034;吻合口上方食管静息压及收缩压增加,具有减轻或防止术后返流的作用,而切断组则没有。结论:无周围组织外侵的食管贲门癌患者切除术中保留迷走神经加胃底重建术,对于防止患者术后反流性食管炎的发生有重要的临床意义。     

IL-1B基因多态性对胃黏膜组织中IL-1β表达的影响

目的:探讨IL-1B基因多态性影响幽门螺旋杆菌(helicobacter pylori,H.pylori或Hp)感染后胃黏膜IL-1β的表达。方法:采用PCR-限制性长度片段多态性(restriction frag-ment length polymorphism,RFLP)分析法检测胃癌低发区117名普通人群IL-1基因多态性。同时比较不同基因型普通人胃黏膜H.pylori阳性和阴性者的IL-1β表达的差异。结果:在胃窦组织中,H.pylori阴性个体的IL-1βmRNA的表达量极少,而H.pylori阳性个体有明显的表达;但在IL-1B-511T/T、C/C和C/T基因型之间差异无统计学意义,P=0·066。在胃体组织中,H.pylori阴性者IL-1βmRNA无明显表达;而在H.pylori阳性者中,IL-1βmRNA表达显著增加(0·44±0·11和0·76±0·14,t=3·2,P=0·02)。而且H.pylori阳性IL-1B-511T/T基因型个体IL-1βmRNA表达比C/T和C/C基因型明显增加(分别为0·86±0·15、0·70±0·16和0·67±0·16,q=2·4和2·7,P=0·043和0·036)。结论:IL-1B基因多态性(-511位点)可促进H.pylori感染后胃体黏膜IL-1βmRNA的表达。肿瘤防治杂志,2005,12(19):1449-1452     

活性碳吸附丝裂霉素局部给药治疗腋淋巴结阳性乳腺癌模型的疗效研究

目的:研究丝裂霉素-活性碳混悬液(MMC-CH)局部注射给药对腋淋巴结阳性的兔乳腺癌模型的治疗效果。方法:30只雌性新西兰兔随机分为三组,每组10只,VX2肿瘤组织块悬液注射法建立乳腺癌模型,腋淋巴结最大径达到5mm时开始治疗。A组:肿瘤周围皮下注射MMC-CH;B组:肿瘤周围皮下注射丝裂霉素水溶剂(MMC-Sol);C组:注射生理盐水。A、B组单次药物剂量0·2mg/kg,每48h重复给药1次,3次治疗后切除淋巴结。比较治疗前后淋巴结体积变化,病理切片观察转移灶癌组织坏死,dTUP末端标记技术(TUNEL)检测癌细胞凋亡指数(AI),组间差异比较采用ANOVA-Dunnett检验。结果:与MMC-Sol相比,局部注射MMC-CH对腋淋巴结癌转移灶表现出更为显著的疗效。治疗后A、B、C组淋巴结平均生长率分别为2·645、3·175和3·518,A组显著低于B、C组(P值分别为0·012和0·000)。A、B、C组平均AI值分别为15·94%、5·18%和4·60%,A组显著高于B组(P=0·000),B组又显著高于C组(P=0·020)。病理检查发现,A组淋巴结转移癌细胞大量坏死。结论:局部注射MMC-CH可有效治疗兔VX2乳腺癌区域淋巴组织转移。     

Laser-induced autofluorescence microscopy of normal and tumor human colonic tissue

Laser-induced autofluorescence (LIAF) spectroscopy has been found to be a promising tool for early cancer diagnosis in various organs, but the reasons responsible for the spectral differences between normal and diseased tissue are still not well understood. In this study, a microspectrophotometer (MSP) system was used to identify the microscopic origins of tissue autofluorescence in the colon under the excitation of a helium-cadmium laser at 442 nm. Colonic tissue samples (normal: n=8, adenocarcinoma: n=10) were obtained from 12 patients with known or suspected malignancies of the colon. The intrinsic fluorescence spectra and images of fresh tissue sections prepared from normal and tumor colonic tissue were measured by the MSP system. Three distinct tissue layers of the colon were found for fluorescence, the mucosa, the submucosa and the muscularis propria, with submucosa being the most fluorescent. Differences in the spectral shape and intensity of the intrinsic fluorescence originating from different colonic layers indicate that fundamentally different fluorophores may be present in the respective tissue layers. There was no significant difference in the intrinsic fluorescence features of the submucosa between normal and tumor colonic tissue, but the fluorescence intensity of the submucosa in tumor tissue was significantly reduced due to the infiltration of tumor cells into the submucosa. The intrinsic fluorescence spectrum peaking at about 520 nm for tumor stroma appeared more evident than that of normal lamina propria. Limited areas of the lamina propria layer in some adenocarcinoma colon exhibited an emission band at about 635 nm, which was attributed to endogenous porphyrins in tumor. Autofluorescence microscopy revealed that differences in the clinically measured autofluorescence spectra between normal and tumor tissue were mainly due to thickening of the tumor mucosa resulting in a reduced submucosa fluorescence contribution, as well as the increased hemoglobin absorption in tumor tissue. Therefore, investigation of the microscopic origins of tissue autofluorescence and images can provide new insights into morphological structures and biochemical components of tissues, which are vital to improve the implementation of the LIAF technique for non-invasive in vivo tissue diagnostics.     

Optimal excitation-emission wavelengths for autofluorescence diagnosis of bladder tumors

Tissue autofluorescence depends on endogenous fluorophores in the tissue, which undergo a change associated with malignant transformation. This change can be detected as an alteration in the spectral profile and intensity of autofluorescence. Our purpose was to determine the optimal excitation and emission wavelengths for autofluorescence diagnosis of bladder cancer. A total of 52 bladder tissue specimens were obtained from 25 patients undergoing mucosal biopsies or surgical resections of bladder tumors. Light-induced autofluorescence measurements were performed to study the spectroscopic differences between normal and malignant bladder tissue. Fluorescence excitation wavelengths varying from 220 to 500 nm were used to induce tissue autofluorescence, and emission spectra were measured in the 280-700 nm range. These spectra were then combined to construct 2-dimensional fluorescence excitation-emission matrices (EEMs). Significant changes in fluorescence intensity of EEMs were observed between normal and tumor bladder tissues, the most marked differences being at the excitation wavelengths of 280 and 330 nm. The diagnostic algorithm based on the combination of the fluorescence peak intensity ratios of I(350)/I(470) at 280 nm excitation and I(390)/I(470) at 330 nm excitation yielded a sensitivity of 100% [95% confidence interval (CI) 0.95-1.0] and specificity of 100% (95% CI 0.90-1.0). The results of the present fluorescence EEM study demonstrate that autofluorescence spectroscopy can distinguish malignant from normal bladder tissue and that excitation wavelengths of 280 and 330 nm are the most significant for differentiation between normal and malignant bladder mucosae with a high degree of diagnostic accuracy.     

Laser-induced autofluorescence spectral ratio reference standard for early discrimination of oral cancer

BACKGROUND: Laser-induced autofluorescence (LIAF) is an emerging noninvasive technique in the biomedical field, especially for cancer detection. The goal of the study was to develop a spectral ratio reference standard (SRRS) to discriminate different grades of oral cancer. METHODS: LIAF emission spectra from oral mucosa were recorded in the 420-720 nm spectral range on a miniature fiberoptic spectrometer from 14 anatomical sites of 35 healthy volunteers and 91 sites of 44 patients, with excitation at 404 nm from a diode laser. RESULTS: Histopathologic analysis of biopsy samples showed that oral mucosa of adjoining malignant sites in patients are not usually normal, but showed various degrees of epithelial dysplasia and hyperplasia. Therefore, instead of using LIAF data from apparently normal lesions of patients as control, spectral data values of the oral mucosa of healthy volunteers were used as control. The autofluorescence emission at 500 nm is characteristic of oral mucosa, whereas in malignant lesions a new peak is seen at 685 nm in addition to the previously reported peaks at 635 and 705 nm. Three spectral ratio reference standard (SRRS) scatterplots were created to differentiate the normal mucosa from hyperplasia, hyperplasia from dysplasia, and dysplasia from squamous cell carcinoma (SCC) using the mean fluorescence intensity ratios (F500/F635, F500/705 and F500/F685) measured from 40 sites in 20 patients and 11 sites in 35 healthy volunteers. During blind tests at 21 sites in 17 patients all 3 SRRS plots showed 100% sensitivity and specificity to discriminate hyperplasia from dysplastic and normal tissues, whereas only the F500/F685 SRRS showed the same sensitivity and specificity to differentiate dysplasia from SCC. CONCLUSIONS: An SRRS criteria based on scatterplots of autofluorescence spectral intensity ratios is described to discriminate oral mucosal variations and screen early stages of tissue progression toward malignancy.     

Analysis of fluorescence in oral squamous cell carcinoma

This study was carried out to examine the spectral properties of the red fluorescence emitted from oral squamous cell carcinoma (SCC). Fluorescent samples obtained from oral cancers induced in hamsters, human oral SCCs, and the medium from cultured oral cancer cell lines were analyzed with a spectrofluorometer with excitation at 404 nm. The spectral profile of the experimentally induced cancers changed with increasing malignancy: peaks at 634 and 672 nm increased and peaks at 520 and 582 nm decreased. A reduction in fluorescence intensity at 582 nm and a rise of intensity at 634 nm were commonly observed in the experimental, clinical, and cell line samples, and the ratio of the fluorescence intensity at 582 nm over that at 634 nm was consistent in all samples. These results suggested that the red fluorescence was emitted by porphyrin, which we believe to be produced by oral SCCs and to accumulate inside or on the surface of cancer tissues in greater amounts with progressing malignancy.     

CD87-positive tumor cells in bone marrow aspirates identified by confocal laser scanning fluorescence microscopy.

Dissemination of single tumor cells to the bone marrow is a common event in cancer. The clinical significance of cytokeratin-positive cells detected in the bone marrow of cancer patients is still a matter of debate. In gastric cancer, overexpression of the receptor (uPAR or CD87) for the serine protease urokinase-type plasminogen activator (uPA) in disseminated cancer cells indicates shorter survival of cancer patients. A new immunofluorescence approach, applying confocal laser scanning microscopy, is introduced to locate CD87 antigen in cytokeratin-positive tumor cells and to quantify the CD87 antigen by consecutive scanning. At first, cytokeratin 8/18/19-positive carcinoma cells are identified at excitation wavelength 488 nm using monoclonal antibody A45B/B3 to the cytokeratins and goat anti-mouse IgG labeled with the fluorochrome Alexa488. Next, CD87 in tumor cells is identified by chicken antibody HU277 to the uPA-receptor and goat anti-chicken IgY labeled with fluorochrome Alexa568 (excitation wavelength 568 nm) and the fluorescence signal quantified on a single cell basis using fluorescently labeled latex beads as the fluorescence reference. From 16 patients with gastric or esophageal carcinoma, bone marrow aspirates were obtained, stained for cytokeratins and CD87 and then subjected to laser scanning fluorescence microscopy. Three of six gastric cancer patients had tumor cells present in the bone marrow of which 2 stained for CD87. Three of ten esophageal carcinoma patients had tumor cells in the bone marrow, all three samples stained for CD87. CD87-positive tumor cells were also dissected from stained bone marrow aspirates by laser microdissection microscope to allow analysis of single cells at the gene level.     

大肠癌体内激光诱发荧光光谱分析

目的 研究体内大肠癌、腺瘤性息肉、慢性炎症与正常组织的激光诱发荧光（ＬＩＦ）光谱，重点探讨癌前病变的特征性光谱规律。方法 将与氮分子激光器（激发波长３３７ｎｍ）耦合的光纤经纤维结肠镜活检孔插入，激光由光纤导入，分别检测８３例患体内病变组织（包括大肠癌３９例，腺瘤性息肉３３例，慢性炎症２３例）与正常组织的ＬＩＦ光谱，所得光谱由同根光纤导出，由ＯＭＡ Ⅲ进行记录、分析处理。结果 癌与正常组织的光谱强     

Understanding the biological basis of autofluorescence imaging for oral cancer detection: high-resolution fluorescence microscopy in viable tissue.

PURPOSE: Autofluorescence imaging is increasingly used to noninvasively identify neoplastic oral cavity lesions. Improving the diagnostic accuracy of these techniques requires a better understanding of the biological basis for optical changes associated with neoplastic transformation in oral tissue. EXPERIMENTAL DESIGN: A total of 49 oral biopsies were considered in this study. The autofluorescence patterns of viable normal, benign, and neoplastic oral tissue were imaged using high-resolution confocal fluorescence microscopy. RESULTS: The autofluorescence properties of oral tissue vary significantly based on anatomic site and pathologic diagnosis. In normal oral tissue, most of the epithelial autofluorescence originates from the cytoplasm of cells in the basal and intermediate regions, whereas structural fibers are responsible for most of the stromal fluorescence. A strongly fluorescent superficial layer was observed in tissues from the palate and the gingiva, which contrasts with the weakly fluorescent superficial layer found in other oral sites. Upon UV excitation, benign inflammation shows decreased epithelial fluorescence, whereas dysplasia displays increased epithelial fluorescence compared with normal oral tissue. Stromal fluorescence in both benign inflammation and dysplasia drops significantly at UV and 488 nm excitation. CONCLUSION: Imaging oral lesions with optical devices/probes that sample mostly stromal fluorescence may result in a similar loss of fluorescence intensity and may fail to distinguish benign from precancerous lesions. Improved diagnostic accuracy may be achieved by designing optical probes/devices that distinguish epithelial fluorescence from stromal fluorescence and by using excitation wavelengths in the UV range.     

A comparative study of normal inspection, autofluorescence and 5-ALA-induced PPIX fluorescence for oral cancer diagnosis.

Fluorescence diagnosis aims to improve the management of oral cancer via early detection of the malignant lesions and better delimitation of the tumor margins. This paper presents a comparative study of normal inspection, combined fluorescence diagnosis (CFD) and its 2 main components, autofluorescence and 5-aminolevulinic acid (5-ALA)-induced protoporphyrin IX (PPIX) fluorescence. Biopsy-controlled fluorescence imaging and spectral analysis were performed on a total of 85 patients with suspected or histologically proven oral carcinoma both before and after topical administration of 5-ALA (200 mg 5-ALA dissolved in 50 ml of H(2)0). Fluorescence excitation was accomplished using filtered light of a xenon short arc lamp (lambda = 375-440 nm). As for CFD, a "streetlight" contrast (red to green) was readily found between malignant and healthy tissue on the acquired images. In terms of tumor localization and delimitation properties, CFD was clearly favorable over either normal inspection or its 2 components in fluorescence imaging. The performance of CFD was found to be impeded by tumor keratinization but to be independent of either tumor staging, grading or localization. In spectral analysis, cancerous tissue showed significantly higher PPIX fluorescence intensities and lower autofluorescence intensities than normal mucosa. There is a great potential for CFD in early detection of oral neoplasms and exact delimitation of the tumors' superficial margins and an advantage over white light inspection and each of its 2 main components. The method is noninvasive, safe and easily reproducible.     

Study of cellular autofluorescence of cultured human cancer cell lines using a fluorescence-activated cell sorter (FACS-IV)

Quantitative cellular autofluorescence measurement of viable cultured human cancer cells and freshly prepared peripheral blood lymphocytes (PBL) obtained from gastric cancer patients and their cultured PBL with T-cell growth factor (CTC) was undertaken on a FACS-IV. The number of cells with fluorescence and its intensity were significantly higher in CTC than in PBL (p less than 0.001). It can be seen that cancer cell lines have different amounts of autofluorescence in values of individual cells. Although the autofluorescence intensity in cancer cells was generally low, one cell line (SC-1) displayed a higher autofluorescence (7.2%) than the others. Our preliminary results suggest that autofluorescence measurement of cells excited by laser beam for early detection of cancer may be limited, and further induction of highly advanced biological techniques will be needed.