S-100B and FDG-PET/CT in Therapy Response Assessment of Melanoma Patients

Abstract

Objective: To compare the value of the tumor marker S-100B protein and fluorodeoxyglucose positron emission tomography/computed tomography (FDG-PET/CT) in patients treated for melanoma metastases. Methods: In 41 patients with proven melanoma metastases, S-100B measurements and FDG-PET/CT were performed before and after therapy. The change of S-100B levels (ΔS-100B) was assessed. In all patients, therapy response was assessed with PET/CT using visual criteria and change of maximal standard uptake value (ΔSUV_max.) or total lesion glycolysis (ΔTLG). Results: In 15 of 41 patients (37%), S-100B values were not suitable because they were normal before and after therapy. In 26 patients, S-100B was suitable for therapy response assessment. PET/CT was suitable for response assessment in all patients. Correlations between ΔS-100B and ΔTLG (r = 0.850, p < 0.001) and between ΔS-100B and ΔSUV_max. (r = 0.818, p < 0.001) were both excellent. A complete agreement between S-100B and PET/CT response assessment was achieved in 22 of 26 patients. In 4 patients, therapy response differed between the S-100B and PET/CT findings, but subsequent S-100B measurements realigned the S-100B results with the later PET/CT findings. Conclusion: In a third of our patients with metastases, the S-100B tumor marker was not suitable for therapy assessment. In these patients, imaging techniques remain necessary, and FDG-PET/CT can be used for response assessment.

Chemotherapy response assessment in stage IV melanoma patients—comparison of 18F-FDG-PET/CT, CT, brain MRI, and tumormarker S-100B

“…In the present study 36% patients failed to show elevated S-100B values despite the presence of proven distant metastases. This is in keeping with a previous study where 15 of 41 patients (37%) showed a false-negative S-100B before therapy of metastases (16).…”

“…Current data regarding therapy assessment of melanoma patients with PET or PET/CT is limited to case reports showing the effect of limb perfusion therapy and one study comparing change of PET/CT findings to change of S-100B values in a mixed population of stage III and stage IV melanoma patients during different therapies (surgery or chemotherapy) (16,17). To our knowledge, this is the first study comparing S-100B, FDG-PET/CT and CT alone for therapy response assessment by using outcome data.…”

“…Preliminary studies showed that PET imaging may help to select the patients for surgery and has influence on the survival (8). 18 F-FDG-PET and -PET/CT is increasingly used for neoadjuvant, adjuvant, curative or palliative chemotherapy response assessment in different malignant tumors such as lymphoma (9-11), oesophageal cancer (12,13), lung cancer (14) and breast cancer (15), but publications regarding PET or PET/CT for therapy response assessment in melanoma patients are still very limited (16,17). Serum S-100B is a useful tumormarker in melanoma patients, indicating the presence of distant metastases and reflecting the tumor burden.…”

18F-FDG PET and PET/CT in the Evaluation of Cancer Treatment Response

“…There are a few reports on the use of 18 F-FDG PET for the assessment of early prediction of response to therapy and outcome in patients with other malignancies, such as ovarian cancer (72,73), uterine cancer (73), head and neck squamous cell carcinoma (74,75), sarcoma (76), mesothelioma (77), and melanoma (78).…”

The value of 18F-FDG-PET/CT imaging for sinonasal malignant melanoma

“…Coregistred 18 F-FDG-PET/CT has been available for a few years and provides such anatometabolic datasets in a single examination. 18 F-FDG-PET/CT has been found to be superior to CT alone and PET alone in staging and evaluation of therapy response in several oncological diseases including malignant melanoma [11][12][13]. 18 F-FDG-PET/CT as a functional and anatomical imaging method provides additional information for surgical therapy planning.…”