Meme Kanserinde Tc-99M V-Dmsa (Pentavalan-Dimerkaptosüksinik Asid) Sintigrafisi ile F-18 Fdg Pet BT Çalışmalarının Karşılaştırılması ve Sintigrafik Çekimler Esnasında Meme Yastığı ile Pozisyonlanmış ve Pozisyonlanmamış Görüntülerin Karşılaştırılmalı Değerlendirilmesi

Abstract

Breast cancer is one of the most common cancers among women. F-18 FDG PET/CT (Fluorine -18FluorodeoxyglucosePositron Emission Tomography) is a metabolic and functional imaging modality which is used for staging, restaging and determining the therapy responsein breast cancer. Tc-99m V-DMSA is an oncofilic tumor imaging agent. Tc-99m V-DMSA uptake has been shown in many types of cancers especially in thyroid medullary carcinoma. Researchs about Tc-99m V-DMSA in breast cancer are limited. In our study, we aimed to compare Tc-99m V-DMSA scintigraphyand F-18 FDG PET/CT in breast cancer. Tc- 99m V-DMSA studies obtained with and without breast positioning have been compared to F-18 FDG PET/CT images to reveal imaging differences and quality.Tc-99m V-DMSA planar and SPECT images versus F-18 FDG PET/CT were compared in 23 breast cancer patients. Qualitative and quantitative evaluation were performed. Uptake activities in tumor were classified from 0 to 3 (VUS; visual uptake score) visually within both of two techniques. For quantitative evaluation SUVmax values of F-18 FDG PET/CT and V-DMSA uptake ratio (DUR) were used.V-DMSA uptake ratio (DUR)was calculated by the following formulation: "DUR=ROItumor/ROIbackground X 100". Nocorrelation was determined between planar Tc-99m V-DMSA and F-18 FDG PET/CT images. In bone metastases, VUS of Tc-99m V-DMSA and F-18 FDG PET/CT showed statically significant, but low correlation (intraclass corelation (ICC)=0.365).Low number of primary breast lesions (8) were detected and statically no significant correlation was found between the studies. In axillary metastatic lesions; 30,33% of FDG positive focishowed Tc-99m V-DMSA positivity. In mediastinal-parasternal-abdominopelvic- other lymph nodes, no statically significant correlation was obtained between the two imaging modalities. Among 43FDG positive lung metastases, only one showed Tc-99m V-DMSA avidity. In liver metastases, 37,5% of FDG positive liver foci were detected by Tc-99m V-DMSA SPECT. Among brain metastases 2 of them showed Tc-99m V-DMSA uptake, while one of them did not show FDG uptake. When the total of primary breast and axillary metastatic foci were considered,no statistically significant correlation was obtained between the Tc- 99m V DMSA SPECT obtained with/without breast positioning and F-18FDG PET/CT. However, there was a tendency of increase in intraclass correlation when breast was positioned (without breast positioning: ICC=0.212;with breast positioning: ICC=0.319).Additional Tc-99m V-DMSA avid metastatic and benign foci were classified. In conclusion, our study is the first clinical research which compares Tc-99m V-DMSAscintigraphy andF-18FDG PET/CT in breast carcinoma. For the evaluation of breast metastasis, we advocate to prefer F-18 FDG PET/CT. In bone metastasis, Tc-99m V-DMSA has low, but statically significant correlation with F-18 FDG PET/CT. Studies with high number of breast lesions are needed to compare Tc-99m V-DMSA scintigraphy and F-18FDG PET/CT in primary breast tumors. SPECT/CT should be applied to all patients for the detection of deeply located foci in the body and to distinguish physiological uptake from pathologic uptake.