PT - JOURNAL ARTICLE AU - Cobben, David C.P. AU - Jager, Piet L. AU - Elsinga, Philip H. AU - Maas, Bram AU - Suurmeijer, Albert J.H. AU - Hoekstra, Harald J. TI - 3′-<sup>18</sup>F-Fluoro-3′-Deoxy-<span class="sc">l</span>-Thymidine: A New Tracer for Staging Metastatic Melanoma? DP - 2003 Dec 01 TA - Journal of Nuclear Medicine PG - 1927--1932 VI - 44 IP - 12 4099 - http://jnm.snmjournals.org/content/44/12/1927.short 4100 - http://jnm.snmjournals.org/content/44/12/1927.full SO - J Nucl Med2003 Dec 01; 44 AB - In this study, the feasibility of 3′-18F-fluoro-3′-deoxy-l-thymidine PET (18F-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 18F-FLT PET scan 1 h after injection of a median 400-MBq dose (range, 185–430 MBq) of 18F-FLT. All 18F-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 18F-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 mm2. Two patients were upstaged by 18F-FLT PET, which was confirmed by CT. In 3 patients, 18F-FLT PET detected a total of 3 additional lesions with therapeutic consequences, without influencing staging. These lesions were initially missed by clinical staging. Conclusion: 18F-FLT PET seems promising for (re)staging purposes in clinical stage III melanoma. Further research is needed, in which 18F-FLT PET should be compared with 18F-FDG PET.