3'-F-18-fluoro-3'-deoxy-L-thymidine:A new tracer for staging metastatic melanoma?

In this study, the feasibility of 3'-F-18-fluoro-3'-deoxy-L-thymidine PET (F-18-FLT PET) for staging patients with clinical stage III melanoma was investigated. Methods: Ten patients with melanoma and metastases to the locoregional draining lymph nodes, clinical stage III-based on physical examination, chest radiography, lactate dehydrogenase, and histopathologic confirmation-underwent a whole-body F-18-FLT PET scan 1 h after injection of a median 400-MBq dose (range, 185-430 MBq) of F-18-FLT. All F-18-FLT PET lesions were verified using the American Joint Committee on Cancer Staging System, which includes physical examination, spiral CT, ultrasound, chest radiography, and histopathologic examinations. Size and mitotic rate of metastatic lymph nodes and skin metastases; were determined. Results: All histopathologic samples and 18F-FLT PET lesions were categorized over anatomic regions and correlated. All locoregional metastases were correctly visualized by F-18-FLT PET. Region-based sensitivity for detection of lymph node metastatic disease was 88%. There were 3 true-negative and 2 false-positive lesions. The detection limit for lymph node metastases appeared to be approximately 6 mm or a mitotic rate of 9 mitoses per 2 mm(2). Two patients were upstaged by F-18-FLT PET, which was confirmed by CT. In 3 patients, F-18-FLT PET detected a total of 3 additional lesions with therapeutic consequences, without influencing staging. These lesions were initially missed by clinical staging. Conclusion: F-18-FLT PET seems promising for (re)staging purposes in clinical stage III melanoma. Further research is needed, in which F-18-FLT PET should be compared with F-18-FDG PET

Prognostic value of the standardized uptake value in esophageal cancer

OBJECTIVE. On PET, the level of tissue glycolysis can be quantified by the accumulation of fluorine-18-fluorodeoxyglucose expressed as the standardized uptake value (SUV). The aims of this study were to investigate the relation between SUV and the stage of disease and whether SUV can be used to predict resectability and survival in patients with esophageal cancer. CONCLUSION. SUV can be used to predict resectability; however, SUV is not an independent factor that can be used to assess survival in patients with esophageal cancer

Detection and grading of soft tissue sarcomas of the extremities with F-18-3 '-fluoro-3 '-deoxy-L-thymidine

Purpose: The aim of the study was to investigate the feasibility of F-18-3'-fluoro-3'-deoxy-L-thymidine positron emission tomography (FLT-PET) for the detection and grading of soft tissue sarcoma (STS). Experimental Design: Nineteen patients with 20 STSs of the extremities were scanned, using attenuation corrected whole-body FLT-PET. Standardized uptake values (SUVs) and tumor:nontumor ratios (TNTs) were compared with histopathological parameters using French and Japanese grading systems. Results: Mean SUV, maximal SUV, and TNT could differentiate between low- grade (grade 1; n = 6) STS and high-grade (grade 2 and 3; n = 14) STS according to the French grading system (P = 0.001). Mean SUV, maximal SUV, and TNT correlated with mitotic score, MIB-1 score, the French and Japanese grading system (e = 0.550-0.747). Conclusions: FLT-PET is able to visualize STS and differentiate between low-grade and high-grade STS. The uptake of FLT correlates with the proliferation of STS

New diagnostic techniques in staging in the surgical treatment of cutaneous malignant melanoma

The emphasis of the research on the surgical treatment of melanoma has been on the resection margins, the role of elective lymph node dissection. in high risk patients and the value of adjuvant regional treatment with hyperthermic isolated lymph perfusion with melphalan. Parallel to this research, new diagnostic techniques, such as Positron Emission Tomography and the introduction of the sentinel lymph node biopsy with advanced laboratory methods such as immuno-histochemical markers, and reverse transcriptase polymerase chain reaction, have been developed to facilitate early detection of metastatic melanoma. The role of these new techniques on the staging and surgical treatment of melanoma is discussed in this paper. (C) 2002 Elsevier Science Ltd. All rights reserved

The value of FDG-PET in the detection, grading and response to therapy of soft tissue and bone sarcomas; a systematic review and meta-analysis

Background: Sarcomas represent a significant diagnostic and therapeutic challenge that requires techniques to provide better assessment of the disease than provided by traditional means. FDG-PET depicts the increased metabolism in abnormal tissues, enabling visualisation and quantification in vivo. The objective of this review was to assess the diagnostic value of FDG-PET in the detection, grading and therapy response of soft tissue and bone sarcomas. Methods: A systematic review and meta-analysis of clinical studies on FDG-PET and sarcomas was conducted. Databases of PubMed, Embase and Cochrane were searched for studies. Besides that, the references of identified studies were reviewed. Three reviewers independently assessed the methodological quality. Statistical pooling was possible for studies concerning detection and grading of studies with mixed sarcomas (soft tissue and bone) and studies with soft tissue sarcomas only. Results: Twenty-nine studies met the inclusion criteria. There was disagreement between the reviewers in 21.5% of the questions from the criteria list. The methodological quality of most of the included studies was poor. Pooled sensitivity, specificity and accuracy of PET for the detection of sarcomas were 0.91, 0.85 and 0.88, respectively. The difference between the mean Standard Uptake Value (SUV) in malignant and benign tumours for the studies concerning mixed and soft tissue sarcomas was statistically significant, as well as the difference in FDG uptake between low and high grade mixed sarcomas. Conclusions: The meta-analysis in this study was limited by the fact that only a few studies had mutual comparable outcome parameters. Moreover, the methodological quality of the studies was generally poor. Nevertheless, our results indicate that FDG-PET can discriminate between sarcomas and benign tumours and low and high grade sarcomas based on the mean SUV. The diagnostic implications of these results have to be investigated, especially the discrimination between benign tumours and low grade sarcomas. Based on this meta-analysis, there is no indication to use FDG-PET in the standard treatment of sarcomas. In the future PET imaging in bone and soft tissue sarcomas should be directed to the clinical implication for the detection and grading of sarcomas and the treatment evaluation of locally advanced sarcomas. (C) 2003 Elsevier Ltd. All rights reserved