血清CEA、CA125、CYFRA21-1、CT联检对肺癌诊断的意义

目的 探讨血清CEA、CA125、CYFRA21-1、CT联检与肺癌临床诊断的相关性.方法 采用放射免疫分析法与电化学发光法对58例肺癌患者和30例正常健康人进行血清标本测定.结果 肺癌组CEA、CA125、CYFRA21-1、CT均高于正常对照组(P<0.01),CEA腺癌组的阳性率明显高于鳞癌组和小细胞癌组(P<0.01),CA125腺癌组、小细胞癌组阳性率明显高于鳞癌组(P<0.01),CYFRA21-1在鳞癌中的阳性率高于腺癌组和小细胞癌组(P<0.01),CT在鳞癌、腺癌、小细胞癌的阳性率,无明显差异(P>0.05).肺癌患者血清CEA、CA125、CYFRA21-1、与CT水平成正相关.结论 CEA、CA125、CYFRA21-1、与CT联检可互补,提高肺癌诊断阳性率.     

肿瘤标志物联检在肺癌诊断中的意义

目的 探讨联合检测血清多项肿瘤标志物在肺癌诊断中的意义.方法 检测96例肺癌,46例良性肺病和58例健康人血清CEA、CA125、NSE和CYFRA21-1的水平.结果 肺癌组血清CEA、CA125、NSE和CYFRA21-1水平显著高于良性肺病组及健康对照组(P<0.01),肺腺癌血清CEA、CA125明显高于肺鳞癌和小细胞肺癌(P<0.05);小细胞肺癌血清NSE明显高于肺腺癌和肺鳞癌(P<0.01);肺鳞癌血清CYFRA21-1明显高于肺腺癌和小细胞肺癌(P<0.05);4项联合检测的灵敏性、准确性均高于单项检测结果.结论 联合检测患者血清CEA、CA1205、NSE和CYFRA21-1有利于肺癌的诊断.     

4种肿瘤标志物在肺癌病理分型、分期中的临床价值

目的：探讨CEA、SCC-Ag、NSE、CA125与肺癌病理分型以及临床特征之间的关系。方法：应用电化学发光方法检测109例肺癌患者血清中4种肿瘤标志物水平。结果：CEA在腺癌中的水平明显高于其他类型的肺癌（P＝0．003）;SCC-Ag在鳞癌中的水平明显高于其他类型的肺癌（P＝0．006）;NSE 在小细胞肺癌中的水平明显高于其他类型的肺癌（P＝0．001）。CEA在T3、T4分期表达的水平明显高于T1和T2分期（P＝0．041）。NSE和CA125在N2和N3期患者中表达水平明显高于N0和N1期患者（P＜0．05）。CEA在有远处转移的患者中表达水平明显高于无转移的患者（P＝0．038）。CEA和SCC-Ag转移部位越多,其表达越高（P＜0．05）。CEA在Ⅳb 期患者中表达水平明显高于Ⅰ＋Ⅱ＋Ⅲ和Ⅳa 期患者（P＝0．037）。CA125在有胸腔积液的患者中表达水平明显高于无胸腔积液的患者（P＝0．001）。结论：CEA对晚期腺癌的诊断价值较高, SCC-Ag是诊断鳞癌有价值的标志物,NSE对小细胞肺癌有较高的诊断价值。CEA与临床分期正相关,高表达预示分期晚,低表达则对分期参考作用小。CEA及SCC-Ag高浓度应高度警惕有无多部位转移,CA125水平高提示可能存在胸膜转移。     

胸水和血清CEA、CA125、CYFRA21-1、NSE和Pro-GRP联合检测对肺癌的诊断价值

目的:探讨联合检测肺癌胸水和血清中癌胚抗原(CEA)、癌抗原125(CA125)、细胞角蛋白19片段(CYFRA21-1)、神经原特异性烯醇化酶(NSE)和胃泌素释放肽前体(Pro-GRP)5 种肿瘤标志物水平在肺癌临床诊断中的应用价值,以期提高鉴别良恶性胸水的能力。方法:用电化学发光法检测93例肺癌患者和54例肺炎性疾病患者的血清及胸水标本CEA、CA125、CYFRA21-1、NSE和Pro-GRP水平。结果:癌性胸水组中CEA、CA125、CYFRA21-1、NSE和Pro-GRP 5种肿瘤标志物平均水平与炎性胸水组比较,差别均有统计学意义(P<0.05);癌性胸水组中CEA、CYFRA21-1、CA125的含量远远高于炎性胸水组（20~600倍）(P<0.01)。肺癌胸水组中CEA、CA125、CYFRA21-1、NSE和Pro-GRP 5种肿瘤标志物水平与肺癌血清组比较,差别均有统计学意义(P<0.05)。肺癌胸水组中CEA、CYFRA21-1、CA125的含量远远高于肺癌血清组（7~80倍）(P<0.01),相比与正常对照组更是有200倍以上的增高(P<0.01),因此胸水中CEA、CYFRA21-1、CA125百倍左右的升高提示恶性肿瘤的存在。将93例癌性胸水和血清分为腺癌、鳞癌和小细胞癌。腺癌、鳞癌和小细胞癌胸水组中CEA、CA125、CYFRA21-1、NSE和Pro-GRP 5种肿瘤标志物含量明显高于炎性胸水组(P<0.01);腺癌胸水组中CEA含量明显高于鳞癌和小细胞癌(P<0.01);鳞癌胸水组中CYFRA21-1含量明显高于腺癌和小细胞癌(P<0.01);小细胞癌胸水组中NSE和Pro-GRP含量明显高于腺癌和鳞癌(P<0.01)。CA125含量在胸水组中腺癌、鳞癌含量明显高于小细胞癌(P<0.01)。5 种标志物单项及联合检测的灵敏度肺癌胸水组均高于肺癌血清组,肺癌胸水中5项联合检测后灵敏度可达99.11%。结论:肺癌组胸水中CEA、CA125、CYFRA21-1、NSE和Pro-GRP 5种肿瘤标志物联合检测有利于良恶性胸水的鉴别诊断,联合检测可以提高肺癌诊断的灵敏度,当肿瘤标志物显著升高时,CEA可作为肺腺癌的肿瘤标志物;CYFRA21-1可作为肺鳞癌的肿瘤标志物;NSE和Pro-GRP可作为小细胞癌的肿瘤标志物;CA125可作为非小细胞肺癌的肿瘤标志物。     

非小细胞肺癌血清中CA125、CEA的浓度及意义

背景与目的CA125、CEA是最早被应用的肿瘤标志物,目前认为CEA在腺癌中有较高的表达,对近3年住院的非小细胞肺癌患者病历进行回顾性分析,发现CA125在非小细胞肺癌中的阳性率远高于以往文献报道。本文旨在讨论非小细胞肺癌血清中CA125、CEA的浓度及意义。方法应用化学发光法检测136例非小细胞肺癌患者,46例肺部良性病变患者及50例健康体检者血清中CA125、CEA含量。结果非小细胞肺癌患者血清CA125含量明显高于肺部良性病变(混合细胞癌除外),差异有统计学意义(P<0.0001),CEA在腺癌及鳞癌患者血清中的含量明显高于肺部良性病变,差异有统计学意义(P<0.0001),CA125、CEA含量在肺部良性病变患者与健康体检者之间无明显差异。CA125在大细胞癌、腺癌、鳞癌、混合细胞癌中的阳性率分别为92.3%、80.2%、54.8%、50%,CEA在腺癌、大细胞癌、鳞癌、混合细胞癌中的阳性率分别为67.4%、0、25.8%、0,CA125/CEA联合检测能提高腺癌的阳性率(90.7%)。进展期非小细胞肺癌CA125、CEA阳性率分别为86.9%、63.6%,CA125在进展期腺癌阳性率达90.9%。结论CA125在非小细胞肺癌中的阳性率较CEA高,在进展期大细胞癌和腺癌中敏感性在90%以上,在协助非小细胞肺癌的诊断中,检测CA125比CEA更有意义。     

血清肿瘤标志物联合检测在肺癌诊断中的价值研究

目的探讨血清肿瘤标志物联合检测在肺癌诊断中的价值。方法采用电化学发光免疫分析法检测86例肺癌患者(肺癌组)、92例肺部良性病变患者(肺良性病变组)和96例健康体检者(健康对照组)的血清神经元特异性烯醇化酶(NSE)、癌胚抗原(CEA)、鳞状细胞癌抗原(SCCAg)、糖类抗原125(CA125)及细胞角质蛋白19片段抗原21-1(CYFRA21-1)水平。对比3组受试者血清肿瘤标志物水平,并比较不同病理类型肺癌患者的血清肿瘤标志物水平及阳性率、不同临床分期肺癌患者的血清肿瘤标志物水平、各种血清肿瘤标志物单项或5项联合检测在肺癌诊断中的价值。结果肺癌组患者的血清NSE、CEA、SCCAg、CA125、CYFRA21-1水平均高于肺良性病变组和健康对照组(P﹤0.05);小细胞肺癌患者的NSE水平及阳性率均高于腺癌患者和鳞癌患者(P﹤0.05),腺癌患者的CEA、CA125水平及CEA阳性率均高于鳞癌患者和小细胞肺癌患者(P﹤0.05),鳞癌患者的SCCAg、CYFRA21-1水平及SCCAg、CYFRA21-1、CA125阳性率均高于腺癌患者和小细胞肺癌患者(P﹤0.05);T3期肺癌患者的NSE、CEA、SCCAg、CA125、CYFRA21-1水平均高于T1期(P﹤0.05),T2期肺癌患者的NSE、CEA、CYFRA21-1水平均高于T1期(P﹤0.05);5项肿瘤标志物联合诊断肺癌的灵敏度、阴性预测值均高于单项诊断,但其特异度仅为81.52%,阳性预测值仅为81.91%。结论不同病理类型及临床分期的肺癌患者肿瘤标志物水平存在较大差异;在肺癌诊断中单项血清肿瘤标志物检测存在一定的局限性,联合检测可提高肺癌诊断的灵敏度和准确度。     

癌胚抗原、鳞状细胞癌抗原、细胞角质蛋白19片段抗原21-1联合检测对肺癌的诊断价值

目的 探讨癌胚抗原（CEA）、鳞状细胞癌抗原（SCC-Ag）、细胞角质蛋白19片段抗原21-1(CYFRA21-1)联合检测对肺癌的诊断价值。方法 选取102例肺癌患者、100例肺部良性疾病患者及80例健康体检者,分别作为恶性组、良性组及对照组。比较3组研究对象的血清CEA、SCC-Ag、CYFRA21-1水平,比较不同病理类型肺癌患者的血清CEA、SCC-Ag、CYFRA21-1水平,分析CEA、SCC-Ag、CYFRA21-1单独及联合检测对肺癌的诊断价值。结果 恶性组患者的血清CEA、SCC-Ag、CYFRA21-1水平均高于良性组和对照组,差异均有统计学意义（P﹤0.05）。102例肺癌患者中,34例腺癌,50例鳞状细胞癌,18例小细胞癌。腺癌患者的血清CEA水平高于鳞状细胞癌和小细胞癌患者,血清SCC-Ag水平低于鳞状细胞癌患者,血清SCC-Ag、CYFRA21-1水平均高于小细胞癌患者,差异均有统计学意义（P﹤0.05）;鳞状细胞癌患者的血清CEA、SCC-Ag、CYFRA21-1水平均高于小细胞癌患者,差异均有统计学意义（P﹤0.05）。CEA、SCC-Ag、CYFRA2...     

血清CYFRA21 1、NSE、CEA、CA125及SCCA联合检测在肺癌诊断中的价值研究

目的探讨联合检测血清细胞角蛋白19片段(CYFRA21 1)、神经元特异性烯醇化酶(NSE)、癌胚抗原(CEA)、糖类抗原125(CA125)、鳞状上皮细胞癌抗原(SCCA)对肺癌的临床诊断价值。方法选取2018年8月至2019年9月在安徽省胸科医院确诊的肺癌患者109例为肺癌组（腺癌61例,鳞癌30例,小细胞癌18例）,肺部良性疾病患者75例为良性肺病组,健康体检者49例为对照组。采用电化学发光法检测各组患者血清中CYFRA21 1、NSE、CEA、CA125及SCCA的表达水平。采用Kruskal Wallis检验、χ2检验比较各组血清CYFRA21 1、NSE、CEA、CA125、SCCA水平和阳性率,采用受试者操作特性曲线（ROC）分析上述5种肿瘤标志物对肺癌的联合诊断价值。结果肺癌组的血清CYFRA21 1、NSE、CEA、CA125、SCCA水平和阳性率明显高于良性肺病组和对照组;腺癌组血清CEA水平高于鳞癌组和小细胞癌组;腺癌组CEA阳性率高于鳞癌组;腺癌组SCCA阳性率高于小细胞癌组;鳞癌组SCCA水平和阳性率高于腺癌组和小细胞癌组;鳞癌组CYFRA21 1水平高于小细胞癌组（P<005）;小细胞癌组NSE水平和阳性率高于腺癌组和鳞癌组,差异均有统计学意义（P<005）。ROC曲线显示5种肿瘤标志物联合检测肺癌及不同病理分型肺癌的ROC曲线下面积（AUC）最大。结论肿瘤标志物CYFRA21 1、NSE、CEA、CA125、SCCA在不同病理分型肺癌中的表达各不相同,联合检测对不同病理分型肺癌的临床诊断价值更大。     

血清CEA、CA125、CYFRA21-1、CT联检对肺癌诊断的意义

目的：探讨血清CEA、CA125、CYFRA21-1、CT联检与肺癌临床诊断的相关性。方法：采用放射免疫分析法与电化学发光法对58例肺癌患者和30例正常健康人进行血清标本测定。结果：肺癌组CEA、CA125、CYFRA21-1、CT均高于正常对照组（P〈0.01）,CEA腺癌组的阳性率明显高于鳞癌组和小细胞癌组（P〈0.01）,CA125腺癌组、小细胞癌组阳性率明显高于鳞癌组（P〈0.01）,CYFRA21-1在鳞癌中的阳性率高于腺癌组和小细胞癌组（P〈0.01）,CT在鳞癌、腺癌、小细胞癌的阳性率,无明显差异（P〉0.05）。肺癌患者血清CEA、CA125、CYFRA21-1、与CT水平成正相关。结论：CEA、CA125、CYFRA21-1、与CT联检可互补,提高肺癌诊断阳性率。     

肺癌患者血清CA125检测的临床应用

目的:探讨CA125对肺癌鉴别诊断和观察疗效的临床意义。方法:采用免疫放射分析法测定健康人和按组织学分类的各类肺癌患者血清CA125水平及阳性率,同时检测各样品的血清CEA水平,进行统计分析。结果:患者组较健康对照组CA125水平显著增高(P<0.01)。肺鳞癌组CA125阳性率为84％,腺癌为65％,腺鳞癌为56％,小细胞肺癌为40％;1例大细胞肺癌CA125检测值为230U/ml、CEA值为18ng/mL。肺鳞癌阳性率较其它组x~2检验有显著意义(p<0.01),CA125与CEA呈正相关(R=0.852)。结论:血清CA125可作为对肺癌早期诊断、鉴别诊断及观察疗效的较好参考指标。     

Tumor markers carcinoembryonic antigen, tissue polypeptide antigen, and carbohydrate antigen 19/9 in liver diseases

The tumor markers carcinoembryonic antigen (CEA), tissue polypeptide antigen (TPA), and carbohydrate antigen 19/9 (CA19/9) have been compared with regard to their sensitivity to liver diseases. All three markers have been found to be sensitive to liver diseases, but to a different degree: TPA rises the most; CEA the least. The sensitivities of TPA and CA19/9 are higher in a group of liver diseases than, for comparison, in a group of colorectal carcinomas.     

Cancer antigen 125, tissue polypeptide antigen, carcinoembryonic antigen, and beta-chain human chorionic gonadotropin as serum markers of epithelial ovarian carcinoma

Cancer antigen 125 (CA 125) is common to most epithelial ovarian tumors. Therefore, it is potentially a good marker of this disease. This hypothesis was evaluated by measuring the serum levels of CA 125 in 81 patients with ovarian cancer (25 with nonactive and 56 with active disease), in 105 patients of both sexes with nonovarian tumors, and in 171 healthy controls of both sexes. The serum levels of three other markers, tissue polypeptide antigen (TPA), carcinoembryonic antigen (CEA), and human chorionic gonadotropin, beta subunit (beta-hCG), were also measured in the same 357 subjects. The results of this study clearly indicate the clinical irrelevance of both CEA and beta-hCG as tumor markers in ovarian carcinomas. Conversely, the clinical usefulness of CA 125 and TPA was confirmed. In particular, CA 125 and TPA showed comparable sensitivity, while CA 125 showed a higher specificity for ovarian cancer than TPA. The association of CA 125 with TPA was very useful in continuous observation of patients with active disease in order to evaluate the clinical effectiveness of the therapy. Moreover, for patients in clinical remission, the markers allowed early detection of a recurrence of the disease.     

Specificity of carcinoembryonic antigen, gastrointestinal cancer-associated antigen, tissue polypeptide antigen, fibrinopeptide A and gamma-glutamyltransferase in the diagnosis and follow-up of gastric cancer

The usefulness and specificity of the main tumor markers (carcinoembryonic antigen, CEA; gastrointestinal cancer-associated antigen, GICA; tissue polypeptide antigen, TPA; fibrinopeptide A, FpA; gamma-glutamyltransferase, gamma-GT) have been investigated in the diagnosis and follow-up of the circumscribed and disseminated gastric cancers (GCs). The comprehensive evaluation of all of these markers has given the most reliable results. For the diagnosis and follow-up of GCs, the present study has shown that the sensitivity and specificity of the above markers have the following decreasing order: FpA, TPA, GICA, CEA, gamma-GT. However gamma-GT has proved to be a reliable index of the presence of hepatic metastases.     

A monkey antigen crossreacting with carcinoembryonic antigen, CEA.

Normal monkey tissues were found to contain an antigen which crossreacts immunologically with the carcinoembryonic antigen (CEA) of the human digestive tract. The monkey antigen reacted with complete or partial identity to the normal crossreacting antigen (NCA) in humans when tested in immunodiffusion against anti-CEA or anti-NCA. Extracts of monkey tissues inhibited in radioimmunoassays measuring human NCA. It is possible that monkey foetuses and colonic tumours contain CEA.     

Biosynthesis, glycosylation and intracellular processing of the neuroglandular antigen, a human melanoma-associated antigen

Neuroglandular antigen (NGA) was identified as a human melanoma-associated antigen by a panel of murine monoclonal antibodies of both IgG2a (LS62, LS76, LS159) and IgG1 (LS113, LS140, LS152) subclasses, developed in this laboratory (L. Sikora, A. Pinto, D. Demetrick, W. Dixon, S. Urbanski, and L. M. Jerry, Int. J. Cancer, 39: 138-145, 1987). Monoclonal antibody LS62 was used to immunoprecipitate NGA from radiolabeled cultured melanoma cells, and it behaved as a heterogeneous glycoprotein "smear" on sodium dodecyl sulfate-polyacrylamide gel electrophoresis analysis (Mr 29,000-70,000). Radioactive pulse-chase time course experiments using human melanoma cells cultured in the presence or absence of inhibitors of protein glycosylation showed that the antigen consisted of a core protein with a molecular weight of 22,000 on sodium dodecyl sulfate-polyacrylamide gel electrophoresis. This molecule was modified by the addition of at least three N-linked oligosaccharide side chains (as revealed by limited N-glycanase digestion) to give a precursor form with a molecular weight of approximately 34,000. Subsequent processing steps yielded a heterogeneous family of glycoproteins with varying amounts of covalently attached carbohydrate. Much of this heterogeneity in both molecular weight and pI (as revealed by two-dimensional electrophoresis) could be removed by treatment of the antigen with neuraminidase, suggesting heavy sialylation of the glycoprotein. NGA could be detected on the surface of melanoma cells by fluorescence-activated cell sorter analysis, surface radioiodination, and, as previously shown, immunoperoxidase staining. However, there was a larger intracellular pool of the molecule and the antigen was rapidly released into the culture supernatant. The function of NGA remains unknown but its elevated expression in transformed melanocytes have prompted this characterization to understand its biochemical nature and relation to other melanoma-associated antigens.     

Coexpression of ganglioside antigen Fuc-GM1, neural-cell adhesion molecule, carcinoembryonic antigen, and carbohydrate tumor-associated antigen CA 50 in lung cancer.

With the aid of specific monoclonal antibodies, tumor tissues from 68 patients with lung cancer were examined for their expression of two small cell lung carcinoma (SCLC) antigens, Fuc-GM1 (fucosyl GM1; IV2FucII3NeuAc GgOse4) and neural-cell adhesion molecule (NCAM), and two broader tumor antigens, carcinoembryonic antigen (CEA) and carbohydrate cancer-associated antigen CA 50. Expression of Fuc-GM1 was seen in 75% and NCAM in 78% of the SCLC specimens, but also in 12 and 20% of non-SCLC. Either or both of these antigens were expressed in more than 90% of SCLC and in 25% of non-SCLC. CEA was found in more than 80% of SCLC and non-SCLC. Expression of CA 50 was seen in 65-68% of non-SCLC and SCLC, showing preference for SCLC and lung adenocarcinoma. In SCLC, cellular expression of Fuc-GM1 was generally seen together with NCAM and CA 50, but rarely with CEA. There was considerable inter- and intratumor heterogeneity in the expression of all four antigens. The results suggest that CEA is the antigen of choice for the detection of lung cancer regardless of histotype. In combined analysis of CEA, CA 50, Fuc-GM1 and NCAM, two patterns of antigen expression were recognized that appear to discriminate between SCLC and non-SCLC tumors, respectively. A considerable fraction of SCLC and non-SCLC tumors, however, exhibited similar patterns of antigen expression. The biological and clinical significance of these observations remains to be investigated.     

Expression of a carbohydrate differentiation antigen, stage-specific embryonic antigen 1, in human colonic adenocarcinoma

The expression of the carbohydrate structure defined by monoclonal antibody to murine stage-specific embryonic antigen 1 (SSEA-1) was examined, using immunofluorescence, in formalin-fixed, paraffin-embedded sections of normal fetal and adult human colon and human colonic adenocarcinoma. SSEA-1 was expressed in all human colonic adenocarcinoma tissues examined, although in some cases the staining was heterogeneous. In normal human colonic mucosa, under the conditions used, faint staining was seen in the lower crypts and in only 26% of the crypts examined. When human fetal colon was tested, SSEA-1 was expressed in much larger amounts and in over 50% of all crypts. Transitional mucosa, immediately adjacent to human colonic adenocarcinomas, was also tested, and in this case, increased SSEA-1 expression was seen not only in the lower crypts but also in the upper crypts and surface epithelium. These results show that the increased expression of SSEA-1 in human colonic adenocarcinoma is an oncodevelopmental marker for this cancer. In addition, the results suggest that increased expression of SSEA-1 may be a preneoplastic change in human colon.     

Moderate expression of prostate-specific membrane antigen, a tissue differentiation antigen and folate hydrolase, facilitates prostate carcinogenesis

Increased expression of PSMA, a differentiation antigen with folate hydrolase activity, is an independent marker of prostate cancer progression. Mice expressing moderate levels of human PSMA in their prostate develop PIN-like lesions by 9 months. The aim of this study was to determine whether PSMA is involved in prostate carcinogenesis and progression and, if so, the possible mechanism by which PSMA may exert its effects. Using prostates from PSMA-transgenic mice, we developed a tissue recombinant model that exhibits small atypical glands with features of adenocarcinoma. This was not observed in tissue recombinants that were composed of prostate tissues from the wild-type siblings. Cells from PSMA-transgenic tissue recombinants have the ability to form colonies in semisolid agar. PSMA may facilitate this phenotype by increasing the invasive ability of cells. Ectopic PSMA expression on PC-3 cells increased the invasive capacity of cells in in vitro invasion assays, which could be competed out by folic acid. These results suggest PSMA facilitates the development of prostate cancer, and the invasive ability of these cells may be modulated by folate levels. These findings show a novel mechanism that may contribute to the known role of folate in cancer prevention, and may lead to the use of PSMA inhibitors as novel chemopreventive agents for prostate cancer. Moreover, our model should prove useful for further dissecting pathways involved in prostate carcinogenesis and progression.     

Cancer antigen 125, carcinoembryonic antigen, and carbohydrate determinant 19-9 in ovarian tumors

The authors studied data of combination assays of tumor markers, because simultaneous elevation of different types of tumor markers in the serum was puzzling. They interpreted such phenomena regarding cancer antigen 125, carcinoembryonic antigen, and carbohydrate determinant 19-9 in ovarian tumors. The tissue expression of the antigens was compared with preoperative serum levels. Several different factors were found to cause the simultaneous elevation of two or three of these markers in the serum. Furthermore, even when the levels of some of the tumor markers were raised in the serum, the ovarian tumor did not always produce the marker by itself. This study indicates that immunohistochemical identification of a marker in tumor tissue is prerequisite to the use of that marker in the serum to monitor disease status.