A Pilot Study for the Feasibility of F-18 FLT-PET in Locally Advanced Breast Cancer: Comparison with F-18 FDG-PET / 핵의학분자영상

PURPOSE: The aim of this study was to investigate the feasibility of 3'-[F-18]fluoro-3'-deoxythymidine positron emission tomography(FLT-PET) for the detection of locally advanced breast cancer and to compare the degree of FLT and 2'-deoxy-2'-[F-18]fluoro-d-glucose(FDG) uptake in primary tumor, lymph nodes and other normal organs. MATERIAL AND METHODS: The study subjects consisted of 22 female patients (mean age; 42+/-6 years) with biopsy-confirmed infiltrating ductal carcinoma between Aug 2005 and Nov 2006. We perfomed conventional imaging workup, FDG-PET and FLT PET/CT. Average tumor size measured by MRI was 7.2+/-3.4 cm. With visual analysis, Tumor and Lymph node uptakes of FLT and FDG were determined by calculation of standardized uptake value (SUV) and tumor to background (TB) ratio. We compared FLT tumor uptake with FDG tumor uptake. We also investigated the correlation between FLT tumor uptake and FDG tumor uptake and the concordant rate with lymph node uptakes of FLT and FDG. FLT and FDG uptakes of bone marrow and liver were measured to compare the biodistribution of each other. RESULTS: All tumor lesions were visually detected in both FLT-PET and FDG-PET. There was no significant correlation between maximal tumor size by MRI and SUVmax of FLT-PET or FDG-PET (p>0.05). SUVmax and SUV75 (average SUV within volume of interest using 75% isocontour) of FLT-PET were significantly lower than those of FDG-PET in primary tumor (SUVmax; 6.3+/-5.2 vs 8.3+/-4.9, p=0.02 / SUV75; 5.3+/-4.3 vs 6.9+/-4.2, p=0.02). There is significant moderate correlation between uptake of FLT and FDG in primary tumor (SUVmax; rho=0.450, p=0.04 / SUV75; rho=0.472, p=0.03). But, TB ratio of FLT-PET was higher than that of FDG-PET(11.7+/-7.7 vs 6.3+/-3.8, p=0.001). The concordant rate between FLT and FDG uptake of lymph node was reasonably good (33/34). The FLT SUVs of liver and bone marrow were 4.2+/-1.2 and 8.3+/-4.9. The FDG SUVs of liver and bone marrow were 1.8+/-0.4 and 1.6+/-0.4. CONCLUSION: The uptakes of FLT were lower than those of FDG, but all patients of this study revealed good FLT uptakes of tumor and lymph node. Because FLT-PET revealed high TB ratio and concordant rate with lymph node uptakes of FDG-PET, FLT-PET could be a useful diagnostic tool in locally advanced breast cancer. But, physiological uptake and individual variation of FLT in bone marrow and liver will limit the diagnosis of bone and liver metastases.

Clinical Significance of Human Sodium Iodide Symporter mRNA Expressions in Primary and Metastatic Papillary Thyroid Carcinoma / 대한내분비학회지

BACKGROUND: The iodide transport into thyroid cells is an essential step in the biosynthesis of thyroid hormones. The sodium iodide symporter (NIS) which is responsible for iodide transport was cloned recently and identified as a plasma membrane glycoprotein. Recent report suggested the absence of human NIS (hNIS) mRNA expression of papillary carcinoma in thyroid indicates absence of response on radioiodine therapy for distant metastasis. To understand the change of hNIS expression at the stage of metastasis in papillary thyroid carcinomas, we evaluated the expression levels of hNIS mRNA in primary and lymph node metastatic papillary carcinoma tissues. METHODS: Seven pairs of primary and lymph node metastatic tissues were included in this study. The level of hNIS mRNA in lymph node metastatic tissues and primary tissues were evaluated by reverse transcriptase-polymerase chain reaction (RT-PCR). The level of GAPDH mRNA was used as internal control. RESULTS: Two among 6 lymph node metastatic tissues did not show hNIS mRNA even with significant hNIS expressions in papillary carcinoma tissues in thyroid. The levels of hNIS expression of remaining 4 lymph node metastatic tissues were lower than those of corresponding primary tissues. Interestingly, one case showed no hNIS expression in primary tissue, but significant hNIS expression in lymph node metastatic tissue. There was no correlation in hNIS mRNA expression between primary and lymph node metastatic tissues. CONCLUSION: No correlation was found in hNIS mRNA expression between primary and lymph node metastatic tissues, suggesting the measurements of hNIS mRNA level in primary tissues may not predict therapeutic response to radioactive iodine.

Clinicopathological Analysis of Laryngeal Leukoplakia: Clinical Follow-up and Immunohistochemical Expression of p53 and PCNA

Laryngeal leukoplakia is seen in a number of pathologic settings such as keratosis without atypia(KWOA), keratosis with atypia(KWA), squamous cell carcinoma in situ(CIS) and invasive squamous cell carcinoma, and it continues to be a confusing and controversial topic for both otolaryngologist and pathologist. This is largely due to the use of ambiguous and inconsistent terminology, the lack of unanimous agreement on the definition of these terms, failure of the clinician to obtain a representative biopsy, and the subjectivity of the pathologist interpreting the biopsy. To evaluate the applicability of the expression pattern of p53 and PCNA in borderline cases of histopathologic classification, we performed a histopathologic analysis of leukoplakia to includ clinical follow-up, correlation of disease progression and degree of atypia, and expression of p53 and PCNA according to the degree of atypia. Histologically, laryngeal leukoplakia included seven cases of KWOA, fourteen cases of KWA (mild-2, moderate-8, severe-4), three cases of CIS, and one case of invasive squamous cell carcinoma. Keratosis with atypia, a moderate degree or more, showed a strong tendency to progress to invasive carcinoma(p<0.05). The degree of p53 and PCNA expression correlated with the degree of atypia(p<0.05). p53-positive cases at the initial biopsy clearly tended to recur and develop into invasive carcinoma(p<0.01).