The accuracy of endoscopic ultrasonography with fine-needle aspiration, integrated positron emission tomography with computed tomography, and computed tomography in restaging patients with esophageal cancer after neoadjuvant chemoradiotherapy

BACKGROUND: Patients with esophageal cancer who receive neoadjuvant chemoradiotherapy are restaged with computed tomography (CT), endoscopic ultrasound with fine needle aspiration (EUS-FNA), and integrated positron emission computed tomography (FDG-PET/CT), and the results affect treatment. METHODS: This is a prospective trial on a consecutive series of patients who had initial chest, abdomen, and pelvis CT scan; EUS-FNA; and fluoro-2-deoxy- d -glucose (FDG)-integrated PET/CT; neoadjuvant chemoradiotherapy; repeat staging tests; pathologic staging; and, if appropriate, resection with lymphadenectomy. The primary objective was to assess the accuracy of these 3 tests in restaging patients after neoadjuvant therapy. RESULTS: There were 48 patients (41 men), and 41 underwent Ivor Lewis esophagogastrectomy with lymphadenectomy. The accuracy of each test for distinguishing pathologic T4 from T1 to T3 disease is 76%, 80%, and 80% for CT scan, EUS-FNA and FDG-PET/CT, respectively. The accuracy for nodal disease was 78%, 78%, and 93% for CT scan, EUS-FNA and FDG-PET/CT, respectively ( P = .04). FDG-PET/CT correctly identified M1b disease in 4 patients, falsely suggested it in 4 patients, and missed it in 2 patients, whereas for CT, it was 3, 3, and 3 patients. Fifteen (31%) patients were complete responders, and FDG-PET/CT accurately predicted complete response in 89% compared with 67% for EUS-FNA ( P = .045) and 71% for CT ( P = .05). CONCLUSIONS: FDG-PET/CT is more accurate than EUS-FNA and CT scan for predicting nodal status and complete responders after neoadjuvant therapy in patients with esophageal cancer. FDG-PET/CT and CT alone provide targets for biopsy, but results are often falsely positive.     

Neoadjuvant therapy of esophageal squamous cell carcinoma: response evaluation by positron emission tomography

OBJECTIVE: To evaluate the use of positron emission tomography using [(18)F]-fluorodeoxyglucose (FDG-PET) to assess the response to neoadjuvant radiotherapy and chemotherapy in patients with locally advanced esophageal cancer. SUMMARY BACKGROUND DATA: Imaging modalities, including endoscopy, endoscopic ultrasound, computed tomography, and magnetic resonance imaging, currently used to evaluate response to neoadjuvant treatment in esophageal cancer do not reliably differentiate between responders and nonresponders. METHODS: Twenty-seven patients with histopathologically proven squamous cell carcinoma of the esophagus, located at or above the tracheal bifurcation, underwent neoadjuvant therapy consisting of external-beam radiotherapy and 5-fluorouracil as a continuous infusion. FDG-PET was performed before and 3 weeks after the end of radiotherapy and chemotherapy (before surgery). Quantitative measurements of tumor FDG uptake were correlated with histopathologic response and patient survival. RESULTS: After neoadjuvant therapy, 24 patients underwent surgery. Histopathologic evaluation revealed less than 10% viable tumor cells in 13 patients (responders) and more than 10% viable tumor cells in 11 patients (nonresponders). In responders, FDG uptake decreased by 72% +/- 11%; in nonresponders, it decreased by only 42% +/- 22%. At a threshold of 52% decrease of FDG uptake compared with baseline, sensitivity to detect response was 100%, with a corresponding specificity of 55%. The positive and negative predictive values were 72% and 100%. Nonresponders to PET scanning had a significantly worse survival after resection than responders. CONCLUSION: FDG-PET is a valuable tool for the noninvasive assessment of histopathologic tumor response after neoadjuvant radiotherapy and chemotherapy.     

FDG-PET imaging for lymph node staging and pathologic tumor response after neoadjuvant treatment of non-small cell lung cancer.

PURPOSE: A number of studies have demonstrated that 18F-fluorodeoxyglucose positron emission tomography (FDG-PET) is effective for staging of lung cancer. However, the efficacy of FDG-PET for staging lung cancer after neoadjuvant treatment is still controversial. This study compared FDG-PET and computed tomography (CT) for lung cancer staging, and evaluated the ability of the two methods to predict the pathologic response of the primary tumor to neoadjuvant treatment. PATIENTS AND METHODS: Twenty-two patients who underwent neoadjuvant treatment followed by surgery were investigated. Eighteen patients received chemoradiotherapy and four patients received chemotherapy only. One hundred and three lymph node stations in the 22 patients were evaluated by FDG-PET and CT. The pathologic responses of the tumors were compared by FDG-uptake and tumor size on CT for the 15 patients who underwent FDG-PET and CT both before and after neoadjuvant treatment. RESULTS: There was no significant difference in the ability of FDG-PET or CT to predict residual viable tumor. Although positive predictive value by FDG-PET (0.29) was lower than that by CT (0.64) (p=0.04) in the mediastinal lymph nodes, there were no statistically significant differences in the other results of lymph nodes by FDG-PET and CT. Both decrease in FDG-uptake and decrease in tumor size by CT after neoadjuvant treatment correlated significantly with pathologic response in the 15 patients (p=0.003 and 0.009, respectively). CONCLUSION: FDG-PET did not appear to offer any advantages over CT for lymph node staging or for predicting the pathologic response after neoadjuvant treatment of non-small cell lung cancer.     

FDG-PET Parameters as Prognostic Factor in Esophageal Cancer Patients: A Review

Background  

¹⁸F-fluorodeoxyglucose positron emission tomography (FDG-PET) has been used extensively to explore whether FDG Uptake can be used to provide prognostic information for esophageal cancer patients. The aim of the present review is to evaluate the literature available to date concerning the potential prognostic value of FDG uptake in esophageal cancer patients, in terms of absolute pretreatment values and of decrease in FDG uptake during or after neoadjuvant therapy.     

三种类型肺癌18氟脱氧葡萄糖摄取量的初步研究

目的探讨肺鳞癌、腺癌、细支气管肺泡癌对18氟脱氧葡萄糖(fluorine -18 fluorode～oxyglucose,FDG)摄取的差异以及影响肺癌摄取FDG的常见因素. 方法对82例肺癌患者行全身或肺部正电子发射体层显像(positron emission tomography,PET)检查,测定肿瘤组织FDG的标准摄取值(standard uptake value,SUV)、最大与平均标准摄取值(SUVmax、SUVmean)、正常肺组织的SUV(SUVlung). 结果 82例患者中,肿瘤组织对FDG的摄取能力均高于相应的正常肺组织(P＜0.01).肺鳞癌、腺癌、细支气管肺泡癌的SUVmax分别为8.42±4.05,5.91±3.91和 2.97±1.10;SUVmean 分别为6.12±2.90,4.35±3.10和 2.25±0.99,三者差异有显著性意义(P＜0.01).SUV与肿瘤的大小呈正相关(P＜0.01).血糖水平与正常肺组织的SUV对肿瘤的SUV有影响(P＜0.05).结论 (1)肺癌组织对FDG的摄取能力高于正常肺组织,而且不同组织类型的肺癌之间SUV值差异有显著性意义.(2)肿瘤的大小与FDG摄取量存在着正相关性.(3)临床上解释肺癌患者PET检查结果时应考虑到血糖等因素的影响.     

Evaluation of 18F-2-deoxy-2-fluoro-<Emphasis Type="SmallCaps">d</Emphasis>-glucose Positron Emission Tomography for Gastric Cancer

Positron emission tomography (PET) with ¹⁸F-2-deoxy-2-fluoro-d-glucose (FDG) has been investigated as a means of detecting certain primary tumors and their metastatic disease in recent years. The aim of this study was to compare the performance of FDG-PET and operative assessment with formal pathologic staging. Altogether, 85 patients had undergone surgical treatment for gastric cancer with curative intent, with FDG-PET preoperatively. The results using FDG-PET were compared with those using computed tomography (CT); they were also correlated with the pathologic findings. For quantitative analysis, the regional tumor uptake was measured by the standard uptake value (SUV) using a region of interest technique. Using FDG-PET, the primary tumor was visualized in 75.2% of patients. A comparison of the FDG uptake and the clinicopathologic findings showed that there was a significant association between FDG uptake and the depth of invasion, the size of the tumor, and lymph node metastasis. FDG-PET scans had less accuracy for diagnosing locoregional lymph nodes than CT because of a significant lack of sensitivity (23.3% vs. 65.0%). The survival rate for patients with high FDG uptake (SUV > 4) was significantly lower than that for those with low FDG uptake (SUV < 4) (p < 0.05). FDG-PET was successful in detecting the primary gastric cancer lesion but not for finding early-stage gastric cancers. Detection of nodal metastasis also was not possible by FDG-PET. However, FDG-PET appears to provide important additional information concerning the aggressiveness of the tumor and the prognosis in patients with gastric cancer.     

18氟脱氧葡萄糖-正电子发射体层显像在贲门癌定性诊断中的价值

目的　探讨18氟脱氧葡萄糖 (FDG) 正电子发射体层显像 (PET)检查在贲门癌定性诊断中的价值。方法　对 1998年 12月至 2 0 0 2年 4月我院收治的 2 7例全身FDG PET检查时贲门部有异常FDG高摄取区域患者的临床资料进行回顾性分析 ,PET结果采用目测法与半定量分析方法进行判断 ,同病理诊断以及随访结果对照。结果　 16例贲门癌患者显影与 11例非特异性显影均被目测法判断为恶性肿瘤 ;半定量分析中 16例贲门癌的最大与平均标准摄取值 (SUVmax与SUVmean)分别为 6 71± 2 75与 5 4 6± 2 31,11例胃底贲门非特异性显影的SUVmax与SUVmean分别为2 99± 0 6 7与 2 38± 0 5 1,贲门癌高于胃底贲门非特异性显影 (Z =- 4 171,Z =- 4 195 ,P均 <0 0 1)。结论　FDG PET检查目测法对于贲门癌肿瘤的定性价值有限 ,半定量分析方法区分良恶性的阈值有待于病例数的积累     

Evaluation of prostate cancer using FDG-PET

The clinical usefulness of 18F-fluorodeoxyglucose positron emission tomography (FDG-PET) was examined in 54 patients with prostate cancer. FDG accumulation was positive in 38 of 54 the prostates (70%), 3 of 8 the lymph node metastases (38%) and 10 of 16 the bone metastases (63%), which suggested that FDG-PET is not superior to other conventional imaging methods as a tool for tumor detection. On the other hand, a quantitative value for FDG uptake in the prostate, expressed as a standardized uptake value (SUV), significantly correlated to the histological grade, clinical stage and serum PSA of the patients. A decrease of SUV was observed in all the patients who responded to endocrine treatment, and the patients with high pre-treatment SUV were shown to be at the risk for disease progression after initial treatment. The present results indicated that FDG-PET could provide us with useful prognostic information for the patients with prostate cancer by evaluating the malignant potential of the tumor.     

18F-Fluorodeoxyglucose Positron Emission Tomography versus Computed Tomography in Predicting Histopathological Response to Epidermal Growth Factor Receptor–Tyrosine Kinase Inhibitor Treatment in Resectable Non-Small Cell Lung Cancer

Purpose

To prospectively evaluate diagnostic computed tomography (CT) and ¹⁸F-fluorodeoxyglucose positron emission tomography/computed tomography (FDG-PET/CT) for identification of histopathologic response to neoadjuvant erlotinib, an epidermal growth factor receptor–tyrosine kinase inhibitor in patients with resectable non-small cell lung cancer (NSCLC).

Methods

This study was designed as an open-label phase 2 trial, performed in four hospitals in the Netherlands. Patients received preoperative erlotinib 150 mg once daily for 3 weeks. CT and FDG-PET/CT were performed at baseline and after 3 weeks of treatment. CT was assessed according to the Response Evaluation Criteria in Solid Tumors (RECIST) version 1.1. FDG-PET/CT, tumor FDG uptake, and changes were measured by standardized uptake values (SUV). Radiologic and metabolic responses were compared to the histopathological response.

Results

Sixty patients were enrolled onto this study. In 53 patients (22 men, 31 women), the combination of CT, FDG-PET/CT, and histopathological evaluation was available for analysis. Three patients (6 %) had radiologic response. According to European Organisation for Research and Treatment of Cancer (EORTC) criteria, 15 patients (28 %) showed metabolic response. In 11 patients, histopathologic response (≥50 % necrosis) was seen. In predicting histopathologic response, relative FDG change in SUV_max showed more SUV_max decrease in the histopathologic response group (?32 %) versus the group with no pathologic response (?4 %) (p = 0.0132). Relative change in tumor size on diagnostic CT was similar in these groups with means close to 0.

Conclusions

FDG-PET/CT has an advantage over CT as a predictive tool to identify histopathologic response after 3 weeks of EGFR–TKI treatment in NSCLC patients.     

Prognostic significance of preoperative [18-F] fluorodeoxyglucose (FDG) positron emission tomography (PET) imaging in patients with resectable soft tissue sarcomas

OBJECTIVE: The objective of this study was to evaluate the prognostic significance of preoperative positron emission tomography (PET) using 2-fluoro-2-deoxy-D-glucose (FDG) by calculating the mean standardized uptake values (SUV) in patients with resectable soft tissue sarcomas (STS). SUMMARY AND BACKGROUND DATA: FDG-PET might be used as an adjunctive tool (in addition to biopsy and radiologic tomography) in the preoperative prognostic assessment of resectable STS. METHODS: A total of 74 adult patients with STS underwent preoperative FDG-PET imaging with calculation of the SUV. Clinicopathologic data and the SUV were analyzed for an association with the clinical outcome. The first and the third quartiles of the SUV distribution function were used as cutoff values (1.59 and 3.6). Survival was estimated by the Kaplan-Meier method. Univariate and multivariate analyses were performed using log-rank test and the Cox proportional hazards regression model. RESULTS: In 55 cases, STS were completely resected (follow up 40 months): 5-year recurrence-free survival rates in patients with SUV <1.59, 1.59 to <3.6, and > or =3.6 were 66%, 24%, and 11%, respectively (P = 0.0034). SUV was a predictor for overall survival (5-year rates: 84% [SUV <1.59], 45% [SUV 1.59 to <3.6], and 38% [SUV > or =3.6]; P = 0.057) and local tumor control (5-year rates: 93% [SUV <1.59], 43% [SUV 1.59 to <3.6], and 15% [SUV > or =3.6]; P = 0.0017). By multivariate analysis, SUV was found to be predictive for recurrence-free survival. The prognostic differences with respect to the SUV were associated with tumor grade (P = 0.002). CONCLUSION: The semiquantitative FDG uptake, as measured by the mean SUV on preoperative PET images in patients with resectable STS, is a useful prognostic parameter. SUV with cutoff values at the first and the third quartiles of the SUV distribution predicted overall survival, recurrence-free survival, and local tumor control. Therefore, FDG-PET can be used to improve the preoperative prognostic assessment in patients with resectable STS.     

Diagnosis of esophageal cancer using positron emission tomography

Fluorodeoxyglucose positron emission tomography (FDG-PET) is more accurate than computed tomography (CT) for evaluating lymph node metastases and for N staging, but less accurate than combined CT and endoscopic ultrasonography (EUS). Lymph nodes located adjacent to the primary lesion tend to be false negatives. We consider that combined FDG-PET and EUS is the most accurate for the detection of lymph node metastasis in esophageal cancer. FDG-PET is also more accurate than CT for detecting distant metastases and improves the detection of stage IV disease compared with the conventional staging modalities. For the diagnosis of recurrence except for perianastomotic recurrence, FDG-PET provides additional information and is more sensitive than conventional work-ups. FDGPET is a valuable tool for the noninvasive assessment of tumor response after neoadjuvant therapy. 11C-methionine (MET) is another tracer for PET that can be used to assess the metabolism of amino acids, since MET accumulates in esophageal malignant tumors. Choline-PET is more accurate than FDG-PET for the detection of mediastinal lymph node metastases.     

Abdominal positron-emission tomography lesions with increased standardized uptake values correlate with intraoperative findings

BACKGROUND: The reporting of standardized uptake value (SUV) on fluoro-2-deoxy-D-glucose positron-emission tomography (FDG-PET) in colorectal cancer is becoming common practice, but its clinical utility remains to be determined. This study was designed to compare FDG-PET uptake as measured by SUV with operative findings. METHODS: A colorectal cancer database was queried to identify patients who underwent FDG-PET scans with reported SUVs followed by exploratory laparotomy within 3 months and compare these results to determine FDG-PET sensitivity. RESULTS: Of 46 patients, 16 (34.8%) were found to be have increased extent of disease intraoperatively than seen on FDG-PET scan. This patient population had a statistically significant decreased mean maximal SUV than the patients whose FDG-PET scan equaled intraoperative findings (P < .025). CONCLUSIONS: This initial study indicates patients with potentially resectable disease by PET scan but decreased FDG uptake should undergo laparoscopic evaluation before performing laparotomy.     

Efficacy of Preoperative Combined 18-Fluorodeoxyglucose Positron Emission Tomography and Computed Tomography for Assessing Primary Rectal Cancer Response to Neoadjuvant Therapy

Purpose Efficacy of F-18 fluorodeoxyglucose positron emission tomography combined with computed tomography (FDG-PET/CT) for determining neoadjuvant therapy response in rectal cancer is not well established. We sought to evaluate serial FDG-PET/CT for assessing tumor down-staging, percentage residual tumor, and complete response or microscopic disease with rectal cancer neoadjuvant therapy. Methods Patients with rectal cancer undergoing neoadjuvant therapy, definitive surgical resection, and FDG-PET/CT before and 4–6 weeks after neoadjuvant treatment were included. Tumors were evaluated pretreatment and on final pathology for size and stage. FDG-PET/CT parameters assessed were visual response score (VRS), standardized uptake value (SUV), PET-derived tumor volume (PETvol), CT-derived tumor volume (CTvol), and total lesion glycolysis (δTLG). Results Twenty-one rectal cancer patients over 3 years underwent neoadjuvant treatment, serial FDG-PET/CT, and resection. Complete response or microscopic disease (n = 7, 33%) was associated with higher ΔCTvol (AUC = 0.82, p = 0.004) and ΔSUV (AUC = 0.79, p = 0.01). Tumor down-staging (n = 14, 67%) was associated with greater ΔPETvol (AUC = 0.82, p < 0.001) and ΔSUV (AUC = 0.82, p < 0.001). Pathologic lymph node disease (n = 7, 33%) correlated with ΔCTvol (AUC = 0.75, p = 0.03) and ΔPETvol (AUC = 0.70, p = 0.08). Conclusion FDG-PET/CT parameters were best for assessing tumor down-staging and percentage of residual tumor after neoadjuvant treatment of rectal cancer and can potentially assist in treatment planning. This work was presented in the plenary session of the 47th Annual Meeting of the Society for Surgery of the Alimentary Tract at the Digestive Disease Week in Los Angeles, CA on 24 May 2006.     

肺部良性结节性病变18F-脱氧葡萄糖正电子发射体层摄影术检查

目的探讨肺部良性结节性病变18F-脱氧葡萄糖(FDG)正电子发射体层摄影术(PET)检查的显像特点.方法回顾分析1998年10月-2004年7月间的47例肺部良性结节性病变患者的FDG-PET检查资料,PET结果采用目测法判读,半定量分析法测量显影病灶的最大与平均标准摄取值(SUVmax与SUVmean)、正常肺组织的标准摄取值(SUVlung).所有患者的病变均手术切除明确诊断,其中17例结核性干酪样坏死、17例钙化及纤维化结节、6例炎性假瘤、3例新型隐球菌性肉芽肿、2例硬化性血管瘤、2例错构瘤.结果 21例病变FDG-PET检查未显影,包括钙化及纤维化结节、错构瘤以及硬化性血管瘤.26例病变或浓或淡显影,半定量分析病变组织的FDG摄取高于相应的正常肺组织(P＜0.001),SUVmax、SUVmean和SUVlung分别为3.04±1.65,2.48±1.35和0.40±0.07,其中9例(35%)患者的SUVmean与11例患者的SUVmax高于2.5;SUV与病变大小无相关性(P＞0.05).结论肺部良性结节性病变中一部分炎性结节表现为高代谢.     

Detection of aortic graft infection by fluorodeoxyglucose positron emission tomography: comparison with computed tomographic findings

OBJECTIVE: Radionuclide imaging with fluorodeoxyglucose (FDG) and positron emission tomography (PET) has been proposed for the identification of vascular graft infection; however, its accuracy has not been determined. We performed this prospective study to compare the usefulness of FDG-PET in the assessment of vascular graft infection relative to computed tomography (CT). METHODS: FDG-PET was performed for 33 consecutive patients with a suspected arterial prosthetic graft infection. The PET images were then assessed visually in terms of the density of uptake. In cases with positive uptake, the pattern of accumulation was also defined, such as focal or diffuse uptake. We compared the diagnostic efficiency of PET with contemporaneous CT in detection of infection of the arterial prosthetic graft. RESULTS: On the basis of the surgical, microbiological, and clinical follow-up findings, the aortic grafts were considered infected in 11 patients and not infected in 22 patients. Although the sensitivity of PET (91%) was higher than that of CT (64%), its specificity (64%) was lower than that of CT (86%). When focal uptake was set as the positive criterion in FDG, the specificity and positive predictive value of PET for the diagnosis of aortic graft infection improved significantly to 95% (P < .05 for both). CONCLUSIONS: Although both techniques are useful in evaluation of patients with suspected aortic graft infection, using the characteristic FDG uptake pattern described previously as a diagnostic criterion made the efficacy of FDG superior to that of CT in the diagnostic assessment of patients with suspected aortic graft infection.     

Pretreatment Gene Expression Profiles Can Be Used to Predict Response to Neoadjuvant Chemoradiotherapy in Esophageal Cancer

BACKGROUND: The use of neoadjuvant therapy, in particular chemoradiotherapy (CRT), in the treatment of esophageal cancer (EC) remains controversial. The ability to predict treatment response in an individual EC patient would greatly aid therapeutic planning. Gene expression profiles of EC were measured and relationship to therapeutic response assessed. METHODS: Tumor biopsy samples taken from 46 EC patients before neoadjuvant CRT were analyzed on 10.5K cDNA microarrays. Response to treatment was assessed and correlated to gene expression patterns by using a support vector machine learning algorithm. RESULTS: Complete clinical response at conclusion of CRT was achieved in 6 of 21 squamous cell carcinoma (SCC) and 11 of 25 adenocarcinoma (AC) patients. CRT response was an independent prognostic factor for survival (P < .001). A range of support vector machine models incorporating 10 to 1000 genes produced a predictive performance of tumor response to CRT peaking at 87% in SCC, but a distinct positive prediction profile was unobtainable for AC. A 32-gene classifier was produced, and by means of this classifier, 10 of 21 SCC patients could be accurately identified as having disease with an incomplete response to therapy, and thus unlikely to benefit from neoadjuvant CRT. CONCLUSIONS: Our study identifies a 32-gene classifier that can be used to predict response to neoadjuvant CRT in SCC. However, because of the molecular diversity between the two histological subtypes of EC, when considering the AC and SCC samples as a single cohort, a predictive profile could not be resolved, and a negative predictive profile was observed for AC.     

Value of positron emission tomography in the diagnosis of recurrent oesophageal carcinoma

BACKGROUND: Positron emission tomography (PET) with [18F]fluorodeoxyglucose (FDG) might be useful for staging oesophageal squamous cell carcinoma (SCC). FDG-PET may be more accurate than computed tomography (CT) in diagnosing lymph node metastasis. This retrospective study compared the ability of FDG-PET and CT to diagnose recurrent oesophageal carcinoma. METHODS: Fifty-five patients with thoracic oesophageal SCC who had undergone radical oesophagectomy were studied. The accuracy of FDG-PET and CT in detecting recurrence during follow-up was calculated using data from the first images generated by either modality that suggested the presence of recurrent disease. Lesions deemed to be equivocal on these scans were considered as positive for recurrence. RESULTS: Twenty-seven of the 55 patients had recurrent disease in a total of 37 organs. Locoregional recurrence was observed in 19 patients (35 per cent). Distant recurrent disease occurred in 15 patients (27 per cent) in 18 organs. Six patients had recurrence in the liver, four in the lung, six in bone and two in distant lymph nodes. FDG-PET showed 96 per cent sensitivity, 68 per cent specificity and 82 per cent accuracy in demonstrating recurrent disease. The corresponding values for CT were 89, 79 and 84 per cent. The sensitivity of FDG-PET was higher than that of CT in detecting locoregional recurrence, but its specificity was lower because of FDG uptake in the gastric tube and thoracic lymph nodes. In distant organs the sensitivity of PET in detecting lung metastasis was lower than that of CT, but its sensitivity for bone metastasis was higher. CONCLUSION: FDG-PET has a larger field than CT. Combined PET-CT would appear to be an appropriate modality for the detection of recurrent oesophageal cancer.     

Preoperative FDG-PET for axillary metastases in patients with breast cancer

HYPOTHESIS: Fludeoxyglucose F 18 (FDG) positron emission tomography (PET) can be used to predict axillary node metastases. DESIGN: Case series. SETTING: Comprehensive breast care center. PATIENTS: Fifty-one women with 54 biopsy-proven invasive breast cancers. INTERVENTION: Whole-body FDG-PET performed before axillary surgery and interpreted blindly. MAIN OUTCOME MEASURES: Axillary FDG activity, quantified by standardized uptake value (SUV); axillary metastases, quantified histologically; and tumor characteristics. RESULTS: There was PET activity in 32 axillae (59%). The SUVs ranged from 0.7 to 11.0. Twenty tumors had an SUV of 2.3 or greater, and 34 had an SUV of less than 2.3. There were no significant differences between these 2 groups except in axillary metastasis size (SUV /=2.3): mean age, 53 vs 58 years (P = .90); mean modified Bloom-Richardson score, 7.7 vs 7.6 (P = .20); lymphovascular invasion present, 25% vs 36% (P = .40); mean Ki-67 level, 25% vs 32% (P = .20); mean tumor size, 2.9 vs 3.2 cm (P = .05); and axillary metastasis size, 0.9 vs 1.7 (P = .001). By adopting an SUV threshold of 2.3, FDG-PET had a sensitivity of 60%, a specificity of 100%, and a positive predictive value of 100%. CONCLUSIONS: Patients with an SUV greater than 2.3 had axillary metastases. This finding obviates the need for sentinel lymph node biopsy or needle biopsy to diagnose axillary involvement. Surgeons can proceed to axillary node dissection to assess the number of nodes involved, eliminate axillary disease, or perhaps provide a survival benefit if preoperative FDG-PET has an SUV greater than 2.3.     

Computed tomography (CT) and positron emission tomography with [F]fluoro-2-deoxy-d-glucose (FDG-PET) images of pulmonary cryptococcosis mimicking lung cancer

BACKGROUND: The objective of this study was to clarify the clinical features of pulmonary cryptococcosis using chest computed tomography (CT) and positron emission tomography with [18F]fluoro-2-deoxy-D-glucose (FDG-PET), with a view to developing appropriate treatment. METHODS: We analyzed the clinical features, and chest CT and FDG-PET characteristics of six cases of pulmonary cryptococcosis that were treated by surgery. The patients comprised four males and two females, ranging in age from 28 to 79 years. RESULTS: All the patients were asymptomatic and had no extrapulmonary involvement. In all cases, chest CT showed nodular shadows. Spiculation and convergence of peripheral vessels were demonstrated in three cases, and pleural indentation in two cases. FDG-PET was performed in four of the cases, and showed accumulation of FDG in all of them. The standard uptake value (SUV) ranged from 0.93 to 4.85. Chest CT findings and accumulation of FDG made it difficult to distinguish pulmonary cryptococcosis from malignancies. Segmentectomy or wedge resection was performed in all cases for pathological diagnosis, and this revealed Cryptococcus fungal bodies. After surgical resection, no sign of relapse has been seen in any of the patients. CONCLUSIONS: Surgical resection is recommended for both diagnosis and treatment of pulmonary cryptococcosis.     

Clinical usefulness of FDG-PET/CT scan imaging in the management of posttransplant lymphoproliferative disease

BACKGROUND: Posttransplant lymphoproliferative disease (PTLD) is, aside skin cancer, the most common malignancy occurring after solid organ transplant in adults. Fluorodeoxyglucose (FDG) positron emission tomography (PET) has proved useful in the management of lymphomas. METHODS: We report our experience with the use of FDG-PET inline with computed tomography (CT) scanning in the management of four transplant recipients with histologically confirmed PTLD, including three monomorphic PTLDs and one polymorphic PTLD. RESULTS: FDG-PET/CT scan at diagnosis showed increased FDG uptake in all examined PTLD lesions, and the disease was upstaged on the basis of FDG-PET/CT scan results over conventional CT scanning in one patient. At the end of treatment, PET/CT scans no longer demonstrated FDG uptake in the original PTLD lesions in all patients. Complete remission of disease persisted for at least 1 year after diagnosis in all. CONCLUSIONS: Our results strongly support that FDG-PET scanning is highly specific for diagnosis and follow-up of PTLD. The clinical relevance of including FDG-PET/CT scanning in the management of PTLD should be evaluated in a larger prospective cohort study.