~（18）FDG-PET显像对胃肠道肿瘤化疗反应的监测

目的探讨18-氟脱氧葡萄糖-正电子发射计算机断层扫描（18FDG-PET）的早期代谢疗效与RECIST标准评价的胃肠道肿瘤化疗最佳客观疗效的关系,评价其在化疗反应监测中的临床价值。方法不可切除的局部晚期和晚期胃肠道肿瘤患者入组,行全身化疗。按RECIST标准和SUV值标准（2疗程化疗后SUV值下降〉30%）分别评价肿瘤客观疗效。用计数资料的χ2检验和相关分析检验比较2疗程后18FDG-PET代谢缓解与RECIST标准的最佳客观疗效是否具有一致性（SPSS10.0）。结果不可切除的局部晚期胃肠道肿瘤3例,晚期胃肠道肿瘤27例。18FDG-PET代谢缓解与按RECIST标准评价的最佳客观疗效具有明显的一致性（P=0.004）。18FDG-PET预测胃肠道肿瘤化疗最佳客观疗效的敏感性、特异性、阳性预测值和阴性预测值分别是91.7%、66.7%、64.7%和92.3%。结论 18FDG-PET可以预测局部晚期和晚期胃肠道肿瘤化疗的最佳客观疗效,在化疗反应监测中具有一定的临床价值。     

18F-FDG PET/CT 与常规CT评价非小细胞肺癌早期化疗疗效的对照研究*

目的:探讨18F-FDGPET/CT 的早期肿瘤代谢疗效与常规CT依据R ECIST 标准（实体瘤疗效评价标准）,评价非小细胞肺癌（non-smallcelllungcancer ,NSCLC ）化疗最佳客观疗效之间的关系。方法:收集2009年9 月至2014年12月山西省肿瘤医院经病理学确诊初治不可切除的局部晚期和晚期非小细胞肺癌（NSCLC ）患者40例,行含铂双药方案全身化疗。PET/CT按SUV 标准（化疗1 个周期后肺部原发癌灶的最高SUV 值下降> 30%）评价肿瘤客观疗效,CT采用RECIST标准评价。配对计数资料采用χ2检验和κ 系数检验,将第1 个周期化疗后的代谢缓解率分别与第1 周期及第2 周期化疗后的最佳客观疗效进行比较,判断两者之间是否具有差异性及一致性。结果:第1 个周期化疗后按SUV 值评价的代谢缓解率与化疗后RECIST评价标准之间差异具有统计学意义（χ2= 5.063,P < 0.05）,并且具有较差的一致性（κ = 0.240,P = 0.085）,与2 个周期化疗后RECIST评价标准差异无统计学意义（χ2=2.083,P > 0.05）,并且具有较好的一致性（κ = 0.413,P = 0.006）;18F-FDGPET/CT 预测NSCLC 2 个周期化疗后最佳客观疗效的灵敏度、特异度、准确度、阳性预测值和阴性预测值分别为 82.4%（14/ 17）、60.9%（14/ 23）、70.0%（28/ 40）、60.9%（14/ 23）和82.4（14/17）% 。结论:18F-FDGPET/CT 能够预测局部晚期和晚期NSCLC 化疗后按RECIST标准评价的最佳客观疗效;18F-FDGPET/CT 相对于常规CT可以更早并准确的评价NSCLC 的化疗疗效。      

18F-FDG PET-CT及实体瘤疗效评价标准评价肺癌早期化疗效果的临床研究

目的：探讨18氟-脱氧葡萄糖正电子发射型计算机断层显像（18F-FDG PET-CT）及胸部CT实体瘤疗效评价标准（RECIST）评价晚期非小细胞肺癌（NSCLC）患者早期化疗效果的临床价值,并根据肿瘤治疗反应调整临床治疗方案。方法回顾性分析经临床诊断不能手术治疗的40例ⅢB和Ⅳ期NSCLC患者的临床资料。分析肿瘤葡萄糖代谢率的改变[最大标准摄取值（SUVmax）变化率]及RECIST预测NSCLC早期化疗疗效情况。结果 PET-CT评价NSCLC患者化疗1个周期结束后有治疗反应者32例（△SUVmax≥20%）,无治疗反应者8例（△SUVmax ＜20%）。2个周期化疗结束后,胸部CT评价有反应者28例,无反应者12例。以RECIST评价疾病进展情况,部分缓解28例,无进展6例,进展6例。其中PET-CT评价有治疗反应者中部分缓解27例,无进展4例,进展1例;PET-CT评价无治疗反应者中部分缓解1例,无进展2例,进展5例。PET-CT在化疗1个周期结束后即可观察到疗效,与RECIST（≥2个周期）相比,差异有统计学意义（χ2＝12.51,P＜0.05）。结论18F-FDG PET-CT在NSCLC患者化疗1个周期后即能反映化疗的敏感性,可为肿瘤再分期、合理选择药物及临床治疗方案的更改提供更可靠的依据。     

18F-FDG-PET/CT在小细胞肺癌化疗疗效中的评估价值

摘 要：［目的］ 探讨18氟脱氧葡萄糖—正电子发射计算机断层扫描(18fluorodeoxyglucose positron emission computed tomography,18F-FDG-PET) 在检测小细胞肺癌(small cell lung cancer,SCLC)化疗客观疗效中的临床价值。 ［方法］ 68例小细胞肺癌患者入组（广泛期35例、局限期33例）,所有患者均行全身化疗,化疗2个周期后根据SUV值及RECIST 标准分别评价疗效,比较两者是否具有一致性,Kaplan-Meier生存分析SUVmax值与患者的生存时间的相关性。［结果］ 18F-FDG-PET代谢缓解与RECIST标准评价的疗效具有明显的一致性(P<0.001)。 ROC曲线分析示SUVmax曲线下面积为0.855,SUVmax值下降>30%患者2年生存率为42.05%,高于SUVmax值下降≤30%者的8.83%(P<0.05);代谢缓解者（SUVmax值下降>30%）的中位生存时间为21.86个月,明显长于代谢无缓解者（SUVmax值下降≤30%）的9.35个月（χ2=11.928,P=0.001）。［结论］ 18F-FDG-PET能够预测小细胞肺癌化疗的疗效,在小细胞肺癌化疗反应监测中具有一定的临床价值。     

调强放疗联合吉西他滨治疗局部晚期非小细胞肺癌近期效果分析

目的 观察调强放疗联合吉西他滨在局部晚期非小细胞肺癌（NSCLC）患者中的近期疗效。方法 回顾性分析局部晚期NSCLC患者45例临床资料。予吉西他滨加顺铂方案诱导化疗2个周期后,分为调强放疗序贯吉西他滨加顺铂方案化疗组和吉西他滨加顺铂方案单纯化疗组。结果 序贯组客观缓解率为65.2 %（15／23）,单独化疗组客观缓解率为31.8 %（7／22）,差异有统计学意义（P＜0.05）;序贯组和单纯化疗组1年生存率分别为66.4 %和45.0 %,两组间差异有统计学意义（P＜0.05）。结论 调强放疗序贯吉西他滨加顺铂方案化疗治疗局部晚期NSCLC较吉西他滨加顺铂方案化疗的近期疗效好,不良反应可以耐受。     

厄罗替尼治疗晚期非小细胞肺癌19例临床疗效

目的评价厄罗替尼治疗ⅢB～Ⅳ期非小细胞肺癌（NSCLC）的疗效和患者不良反应。方法19例患者均为经病理证实的、至少接受过一种方案全身化疗的晚期NSCLC患者。厄罗替尼150mg／次,1次／d,口服,直至病情进展或出现不能耐受的不良反应。采用实体瘤疗效评价标准（RECIST）评价疗效,美国国立癌症研究所毒性评价标准（CTCAE）评价不良反应。结果19例患者客观缓解率（ORR）为21．1％（4／19）。疾病控制率（完全缓解＋部分缓解＋稳定）为84．2％（16／19）,疾病无进展生存时间（PFS）3～36个月,中位PFS7．5个月;生存时间9～39个月,中位生存时间15．9个月。不良反应主要是皮疹16例（84．2％）,腹泻11例（57．9％）,多为Ⅰ～Ⅱ度;Ⅲ度丙氨酸氨基转移酶升高1例;未出现Ⅳ度药物相关不良反应。结论厄罗替尼对既往化疗失败的局部晚期或转移性NSCLC患者有较好的疗效和安全性。     

GC方案作为诱导方案治疗老年局部晚期非小细胞肺癌的临床观察

目的：评价吉西他滨联合卡铂在老年不可手术的局部晚期非小细胞肺癌（non-small cell lung canc-er,NSCLC）作为诱导方案的疗效和安全性。方法：对于有明确的病理或细胞学诊断,年龄在65-75岁的晚期不可手术的NSCLC患者78例,应用GEM联合CBP化疗,GEM1000mg/m2静脉滴入第1、8天,CBP AUC为4,在第1天给药。21d为1个周期,共2个周期。并按RECIST标准评价疗效和WHO不良反应分级标准记录不良反应。结果：可评价的78例患者,共完成156个周期化疗,CR 0例,PR 32例,NC 37例,PD 9例,总有效率为41.0%。主要不良反应为骨髓抑制和消化道反应。结论：GEM联合CBP作为老年不可手术的晚期NSCLC诱导治疗是安全有效的,不良反应可以接受。     

三维适形放疗同步单药化疗治疗老年局部晚期非小细胞肺癌的疗效观察

目的观察三维适形放疗同步单药化疗治疗老年局部晚期非小细胞肺癌（NSCLC）的临床疗效和毒副反应。方法放疗选用三维适形放疗（3D-CRT）,化疗选用长春瑞滨（盖诺）单药,25mg/m2,静脉推注,d1,8,3周重复。于放疗第1天开始化疗,放疗期间共行2个周期化疗,放疗结束后再化疗2个周期。结果完全缓解（CR）21.2%,部分缓解（PR）54.5%,总有效率（RR）75.8%。Ⅲ～Ⅳ度不良反应发生率比较低。结论 3D-CRT同步单药化疗治疗老年局部晚期NSCLC疗效较好,毒副反应能耐受,安全可行。     

以培美曲塞为基础的联合化疗方案治疗老年人晚期非鳞非小细胞肺癌的临床研究

目的 评估以培美曲塞为基础的联合化疗方案一线治疗老年晚期非鳞非小细胞肺癌（NSCLC）患者的临床效果和安全性。方法 回顾性分析经病理学确诊的老年晚期非鳞NSCLC患者40例,采用培美曲塞联合顺铂或卡铂方案全身化疗,其中培美曲塞联合顺铂组（A组）18例,培美曲塞联合卡铂组（B组）22例,根据实体瘤疗效评价标准（RECIST）和美国国家癌症研究所化疗毒性分级标准（NCI-CTC AE）对疗效和不良反应进行评估。结果 40例老年晚期非鳞NSCLC患者经培美曲塞为基础的化疗方案治疗后,部分缓解 17例,稳定16例,进展7例,客观有效率（ORR）42.5 %（17／40）,疾病控制率（DCR）82.5 %（33／40）,中位无进展生存（PFS）5.3个月,1年生存率63.2 %（24／38）。亚组分析A组与B组相比,ORR分别为44.4 %（8／18）、40.9 %（9／22）,DCR分别为83.3 %（15／18）、81.8 %（18／22）,PFS分别为5.5、5.1个月,1年生存率分别为64.7 %（11／17）、 61.9 %（13／21）,前者均高于后者,但差异均无统计学意义（均P＞0.05）。全组患者不良反应较轻,主要为骨髓抑制和胃肠道反应,多为1、2级。结论 在老年患者中,应用以培美曲塞为基础的方案治疗晚期非鳞NSCLC具有良好效果,且不良反应较小,能耐受,可推荐作为体力状况（PS）评分较好的老年晚期非鳞NSCLC的一线化疗方案。     

吉西他滨联合顺铂治疗晚期非小细胞肺癌的临床研究

 目的 研究吉西他滨（GEM）、顺铂（DDP）二药联合（GP方案）化疗对晚期非小细胞肺癌（NSCLC）的客观疗效和毒副反应。方法 GEM 1000 mg／m2，第1、8天，DDP 75 mg／m2，总剂量分为3 d使用，第1～3天，21 d为1周期。按WHO标准评价疗效，采用美国国立癌症研究中心（NCI）CTC标准评价毒副反应，同时评估临床受益（CBR）率。结果 46例均可评价疗效，其中完全缓解（CR）1例，部分缓解（PR） 21例，有效率（RR）47.8 %，中位生存期10.3个月，CBR 78.3 %。毒副反应为骨髓抑制、恶心、呕吐等。结论 GP方案治疗晚期NSCLC疗效较高，毒副反应可耐受。     

Positron emission tomography in non-small-cell lung cancer: prediction of response to chemotherapy by quantitative assessment of glucose use.

PURPOSE: To prospectively evaluate the use of positron emission tomography with the glucose analog fluorodeoxyglucose (FDG-PET) to predict response to chemotherapy in patients with advanced non-small-cell lung cancer (NSCLC). PATIENTS AND METHODS: Patients with stage IIIB or IV NSCLC scheduled to undergo platinum-based chemotherapy were eligible for this study. Patients were studied by FDG-PET before and after the first cycle of therapy. Based on previous studies, a reduction of tumor FDG uptake by more than 20% as assessed by standardized uptake values (SUV) was used as a criterion for a metabolic response. Furthermore, changes in tumor SUVs were compared with changes in FDG net-influx constants (Ki) and tumor/muscle ratios (t/m). RESULTS: Fifty-seven patients were included in the study. There was a close correlation between metabolic response and best response to therapy according to Response Evaluation Criteria in Solid Tumors (P <.0001; sensitivity and specificity for prediction of best response, 95% and 74%, respectively). Median time to progression and overall survival were significantly longer for metabolic responders than for metabolic nonresponders (163 v 54 days and 252 days v 151 days, respectively). Similar results were obtained when Ki was used to assess tumor glucose use, whereas changes in t/m showed considerable overlap between responding and nonresponding tumors. CONCLUSION: In NSCLC, reduction of metabolic activity after one cycle of chemotherapy is closely correlated with final outcome of therapy. Using metabolic response as an end point may shorten the duration of phase II studies evaluating new cytotoxic drugs and may decrease the morbidity and costs of therapy in nonresponding patients.     

Repeat 18F-FDG PET for monitoring neoadjuvant chemotherapy in patients with stage III non-small cell lung cancer

PURPOSE: The relevance of (18)F-FDG PET for staging non-small cell lung cancer (NSCLC), in particular for the detection of lymph node or distant metastases, has been shown in several studies. The value of FDG-PET for therapy monitoring in NSCLC, in contrast, has not yet been sufficiently analysed. Aim of this study was to evaluate FDG-PET for monitoring treatment response during and after neoadjuvant radiochemotherapy (NARCT) in advanced NSCLC. METHODS: Sixty-five patients with histologically proven NSCLC stage III initially underwent three FDG-PET investigations, during NARCT prior to initiating radiation, and post-NARCT. Changes of FDG-uptake in the primary tumour at two time-points during NARCT were analysed concerning their impact on long-term survival. RESULTS: The mean maximum FDG uptake (standardized uptake value, SUVmax) of the whole group decreased significantly during NARCT (SUVmax PET 1: 14.9+/-4.0, SUVmax PET 3: 5.5+/-2.4, p=0.004). The difference between initial FDG uptake (PET 1) and uptake after induction chemotherapy (PET 2) was found to be highly predictive for long-term survival patients which had a greater than 60% decreases in their SUV change had a significantly longer survival than those below this threshold (5-year-survival 60% versus 15%, p=0.0007). Patients who had a lower than 25% decrease in their SUV change had a 5-years-survival lower than 5%. Furthermore, the difference between initial FDG uptake (PET 1) and uptake after completion of the whole NARCT (PET 3) was predictive for survival when 75% was applied as cut-off (p=0.02). However, the level of significance was considerably lower. CONCLUSION: FDG-PET is suitable for therapy monitoring in patients with stage III NSCLC. The decrease of FDG uptake during induction chemotherapy is highly predictive for patient outcome.     

Prediction of response to preoperative chemotherapy in gastric carcinoma by metabolic imaging: results of a prospective trial.

PURPOSE: We prospectively evaluated the predictive value of therapy-induced reduction of tumor glucose use for subsequent response and patient survival in patients with gastric cancer treated by preoperative chemotherapy. PATIENTS AND METHODS: Forty-four consecutive patients with locally advanced gastric carcinomas were studied by positron emission tomography with the glucose analog fluorine-18 fluorodeoxyglucose (FDG-PET) at baseline and 14 days after initiation of cisplatin-based polychemotherapy. On the basis of a previous study, a reduction of tumor FDG uptake by more than 35% was used as a criterion for a metabolic response. The metabolic response in FDG-PET was correlated with histopathologic response after completion of therapy (< 10% viable tumor cells in the resected specimen) and patient survival. RESULTS: Thirty-five (80%) of the 44 tumors were visualized with sufficient contrast for quantitative analysis (two of 19 intestinal and seven of 25 nonintestinal tumors showed only low FDG uptake). In the 35 assessable patients, PET imaging after 14 days of therapy correctly predicted histopathologic response after 3 months of therapy in 10 (77%) of 13 responders and 19 (86%) of 22 nonresponders. Median overall survival for patients with a metabolic response has not been reached (2-year survival rate, 90%); for patients without a metabolic response, median survival was only 18.9 months (2-year survival rate, 25%; P =.002) CONCLUSION: This study prospectively demonstrates that in patients with gastric cancer, response to preoperative chemotherapy can be predicted by FDG-PET early during the course of therapy. By avoiding the morbidity and costs of ineffective therapy, FDG-PET imaging may markedly facilitate the use of preoperative chemotherapy.     

Early metabolic response evaluation by fluorine-18 fluorodeoxyglucose positron emission tomography allows in vivo testing of chemosensitivity in gastric cancer: long-term results of a prospective study.

PURPOSE: We prospectively evaluated the predictive value of positron emission tomography using fluorine-18 fluorodeoxyglucose (FDG-PET) for in vivo testing of chemosensitivity in locally advanced gastric cancer using an a priori definition of metabolic response (a decrease of >35% of the standard uptake value). The goal of the study was the definition of biologically different groups of patients prior to or early during induction therapy, with special emphasis on FDG non-avid tumors. EXPERIMENTAL DESIGN: Based on our data, which was published in 2003, at least 36 patients with metabolic response or FDG non-avid tumors had to be recruited for an analysis of the group of FDG non-avid tumors with sufficient statistical power. Seventy-one patients (32 metabolic nonresponders, 17 metabolic responders, and 22 patients with FDG non-avid tumors) underwent FDG-PET at baseline. In FDG-avid tumors, FDG-PET was repeated 14 days after the initiation of chemotherapy. RESULTS: Metabolic responders (17 of 49) showed a high histopathologic response rate (69%) and a favorable prognosis (median survival not reached), whereas metabolic nonresponders (32 of 49) had a poor prognosis (median survival, 24.1 months) and showed a histopathologic response in 17%. The histopathologic response rate (24%) for FDG-PET non-avid patients showed no significant difference compared with FDG-avid nonresponders (P=0.72). Survival of FDG non-avid patients was 36.7 months (not significantly different from FDG-avid nonresponders, 24.1 months, P=0.46). CONCLUSION: In locally advanced gastric cancer, three different metabolic groups exist. Response and survival was predicted by PET in FDG-avid tumors. Metabolic response assessment was not possible in FDG non-avid tumors; however, due to unfavorable outcome, therapy modification might also be considered in FDG non-avid tumors.     

Prediction of response to neoadjuvant chemotherapy by sequential F-18-fluorodeoxyglucose positron emission tomography in patients with advanced-stage ovarian cancer.

PURPOSE: The aim of this study was to evaluate sequential F-18-fluorodeoxyglucose positron emission tomography (FDG-PET) to predict patient outcome after the first and third cycle of neoadjuvant chemotherapy in advanced-stage (International Federation of Gynecology and Obstetrics stages IIIC and IV) ovarian cancer. PATIENTS AND METHODS: Thirty-three patients received three cycles of carboplatin-based chemotherapy, followed by cytoreductive surgery. Quantitative FDG-PET of the abdomen and pelvis was acquired before treatment and after the first and third cycle of chemotherapy. Changes in tumoral FDG uptake, expressed as standardized uptake values (SUV), were compared with clinical and histopathologic response; overall survival served as a reference. RESULTS: A significant correlation was observed between FDG-PET metabolic response after the first (P = .008) and third (P = .005) cycle of chemotherapy and overall survival. By using a threshold for decrease in SUV from baseline of 20% after the first cycle, median overall survival was 38.3 months in metabolic responders compared with 23.1 months in metabolic nonresponders. At a threshold of 55% decrease in SUV after the third cycle median overall survival was 38.9 months in metabolic responders compared with 19.7 months in nonresponders. There was no correlation between clinical response criteria (P = .7) or CA125 response criteria (P = .5) and overall survival. There was only a weak correlation (P = .09) between histopathologic response criteria and overall survival. CONCLUSION: Sequential FDG-PET predicted patient outcome as early as after the first cycle of neoadjuvant chemotherapy and was more accurate than clinical or histopathologic response criteria including changes in tumor marker CA125. FDG-PET appears to be a promising tool for early prediction of response to chemotherapy.     

Usefulness of FDG-PET for early prediction of the response to gefitinib in non-small cell lung cancer

Increased tumor uptake of (18)F-fluorodeoxyglucose (FDG) measured by positron emission tomography (PET) reflects glucose metabolism and proliferative activity of tumor cells. We conducted a study to assess the usefulness of FDG-PET for early prediction of the response to gefitinib, an epidermal growth factor receptor (EGFR) tyrosine kinase inhibitor (TKI), in advanced non-small cell lung cancer (NSCLC). Five NSCLC patients underwent FDG-PET to evaluate changes in FDG uptake at day 2 and 4 weeks after the initiation of gefitinib therapy compared with FDG-PET prior to therapy. FDG uptake was evaluated as the maximum standardized uptake value (SUVmax) of the target lesions, which were assessable by conventional CT. Based on the CT evaluation, two patients exhibited a partial response (PR), two patients had stable disease (SD) with a minor response, and one patient had progressive disease (PD). In patients with PR and SD, SUVmax decreased by 61+/-18% (standard deviation) and 59+/-12%, respectively, on day 2, and by 26+/-6 and 43+/-10%, respectively, at 4 weeks after the initiation of gefitinib. Two patients with SD had decreased FDG uptake within 2 days of initiation of therapy, and achieved progression-free survival (PFS) of more than 12 months. In contrast, SUVmax increased up to 153+/-21% at 2 days and 232+/-73% at 4 weeks in a patient with PD. The present preliminary study suggests that FDG-PET may be able to predict response to gefitinib in the early stage of therapy in patients with advanced NSCLC and may have a potential prognostic role.     

FDG-PET in the prediction of pathologic response after neoadjuvant chemoradiotherapy in locally advanced, resectable esophageal cancer

PURPOSE: To assess the efficacy of 18Fluorodeoxyglucose-positron emission tomography (FDG-PET) for predicting a pathologic response in locally advanced esophageal cancer after neoadjuvant chemoradiotherapy. METHODS AND MATERIALS: All enrolled patients were treated with neoadjuvant chemoradiotherapy followed by esophagectomy and underwent two FDG-PET scans, before and after neoadjuvant chemoradiotherapy. We compared the results of the preoperative FDG-PET scans with the pathologic results. RESULTS: From July 2001 to July 2004, 32 patients (29 men and 3 women) were enrolled in this study. Pathologic complete response (pCR) in the esophagus was achieved in 21 of 32 patients (66%). The sensitivity, specificity, positive predictive value (PPV), and negative predictive value (NPV) in the primary tumors of the preoperative FDG-PET were 27%, 95%, 75%, and 71%, respectively. In regional lymph nodes, these values were 16%, 98%, 36%, and 93%, respectively. The mean standardized uptake value (SUV) of primary tumors was initially 5.6 +/- 3.6 and changed to 1.5 +/- 1.3 after neoadjuvant chemoradiotherapy (p < 0.05). If analysis of metabolic response (SUV decrease, DeltaSUV) was limited to initially highly metabolic primary tumors (SUV > or =4.0), pathologic response was correlated with metabolic response (p = 0.006). CONCLUSIONS: This study suggested that the pathologic response of an initially highly metabolic tumor after neoadjuvant chemoradiotherapy could be correlated with the metabolic response, and FDG-PET can provide additional information on tumor response to chemoradiotherapy.     

Early evaluation of the response to radiotherapy of patients with squamous cell carcinoma of the head and neck using 18FDG-PET

The aim was to evaluate the efficacy of positron emission tomography (PET) with 2-[F-18]fluoro-2-deoxy-d-glucose (FDG) in early discrimination of response to definitive radiotherapy (RT) in patients with squamous cell carcinoma of the head and neck (SCCHN). Twenty-four patients who underwent FDG-PET scans before and after radiotherapy for nondisseminated SCCHN at the Asan Medical Center between August 2001 and September 2002 were prospectively evaluated. Initial FDG-PET scans were performed within 1 month before RT, and follow-up FDG-PET scans were performed 1 month after completion of RT. FDG-PET images were analyzed by standard uptake value (SUV). All patients were followed for more than 6 months. Pretreatment SUV ranged from 3.4 to 14.0 (median, 6.0), while posttreatment SUV ranged from ground level to 7.7 (median, 2.0). In evaluating residual tumors in these SCCHN patients, the overall sensitivity of FDG-PET was 100%, while its overall specificity was 87%. FDG-PET is effective in evaluating the response to radiation in patients with SCCHN. Timing the follow-up FDG-PET scan 1 month after completion of RT was not too rapid for evaluating the response to radiation.