Prognostic Value of Bone Marrow F-18 FDG Uptake in Patients with Advanced-Stage Diffuse Large B-Cell Lymphoma / 대한핵의학회잡지

Purpose@#We assessed prognostic implication of bone marrow uptake on baseline F-18 fluorodeoxyglucose positron emission tomography/computed tomography (FDG PET/CT) in patients with advanced-stage diffuse large B-cell lymphoma (DLBCL). @*Methods@#We retrospectively reviewed 140 patients with stage III and IV DLBCL, who underwent baseline F-18 FDG PET/CT at diagnosis. Bone marrow uptake on F-18 FDG PET/CT (BM FDG) was compared with findings on bone marrow biopsy (BMB), and patients were grouped based on these results: BMB-positive and BM FDG-positive (group 1), BMB-positive and BM FDG-negative (group 2), BMB-negative and BM FDG-positive (group 3), and BMB-negative and BM FDG-negative (group 4). The prognostic value of clinicopathologic factors and BM FDG for predicting progression-free survival (PFS) and overall survival (OS) was assessed using a Cox proportional hazards model. Differences in PFS and OS were examined by the Kaplan-Meier method. @*Results@#BMB was the only significant indicator in predicting PFS, and age, IPI score higher than 3, and BM FDG significantly predicted OS. Group 1 showed inferior PFS than group 2 (median PFS, 7.4 vs. 13.9 months; p = 0.04). In contrast, there was no significant difference either in PFS or OS between group 2 and group 3. @*Conclusion@#We showed that BM FDG-positive predicted a poorer survival in patients with advanced stage DBLCL. We also found that BMB-negative and BM FDG-positive patients had similar PFS or OS to BMB-positive and BM FDG-negative patients. Further study in a larger population is needed to clarify clinical significance of BM FDG in these patients.

Malignant Transformation of an Epidermoid Cyst in an Intrapancreatic Accessory Spleen: A Case Report / 대한핵의학회잡지

A 33-year-old man was evaluated because of an incidentally found cyst in the pancreatic tail, which was first seen 6 years ago. The cyst was a unilocular cystic mass, 13.0 cm in diameter, and had increased in size in last 2 months. On F-18 fluorodeoxyglucose positron emission tomography/computed tomography (FDG PET/CT), the cystic wall showed increased FDG uptake. The patient underwent distal pancreatectomy with suspicion of mucinous cystic neoplasm of the pancreas. The mass turned out to be a squamous carcinoma arising from an epidermoid cyst in an intrapancreatic accessory spleen (ECIPAS). FDG PET/CT may assist recognition of a potential malignant lesion arising from an ECIPAS.

Evaluation of ¹⁸F-FDG PET/CT Parameters for Detection of Lymph Node Metastasis in Cutaneous Melanoma / 대한핵의학회잡지

PURPOSE: The purpose of this study was to investigate the value of ¹⁸F-fluorodeoxyglucose positron emission tomography/computed tomography (FDG PET/CT) parameters in the detection of regional lymph node (LN) metastasis in patients with cutaneous melanoma.METHODS: We evaluated patients with cutaneous melanoma who underwent FDG PET/CT for initial staging or recurrence evaluation. A total of 103 patients were enrolled, and 165 LNs were evaluated. LNs that were confirmed pathologically or by follow-up imaging were included in this study. PET parameters, including maximum standardized uptake value (SUVmax), total lesion glycolysis and tumour-to-liver ratio, were used to determine the presence of metastases, and the results were compared with CT-determined LN metastasis. Receiver operating characteristic (ROC) curve analysis was used to determine the optimal cut-off values of the FDG PET parameters.RESULTS: A total of 93 LNs were malignant, and 84 LNs were smaller than 10 mm. In all 165 LNs, an SUVmax of >2.51 showed a sensitivity of 73.1%, a specificity of 88.9%, and an accuracy of 80.0% in detecting metastatic LNs. CT showed a higher specificity (87.3%) and lower accuracy (65.5%). For non-enlarged regional LNs ( < 10 mm), an SUVmax cut-off value of 1.4 showed the highest negative predictive value (81.3%). For enlarged LNs (≥10 mm), an SUVmax cut-off value of 2.4 showed the highest sensitivity (90.7%) and accuracy (88.9%) in detecting metastatic LNs.CONCLUSIONS: In patients with cutaneous melanoma, an SUVmax of >2.4 showed a high sensitivity (91%) and accuracy (89%) in detecting metastasis in LNs ≥1 cm, and LNs < 1 cm with an SUVmax < 1.4 were likely to be benign.

Evaluation of ¹⁸F-FDG PET/CT Parameters for Detection of Lymph Node Metastasis in Cutaneous Melanoma / 대한핵의학회잡지

PURPOSE@#The purpose of this study was to investigate the value of ¹⁸F-fluorodeoxyglucose positron emission tomography/computed tomography (FDG PET/CT) parameters in the detection of regional lymph node (LN) metastasis in patients with cutaneous melanoma.@*METHODS@#We evaluated patients with cutaneous melanoma who underwent FDG PET/CT for initial staging or recurrence evaluation. A total of 103 patients were enrolled, and 165 LNs were evaluated. LNs that were confirmed pathologically or by follow-up imaging were included in this study. PET parameters, including maximum standardized uptake value (SUVmax), total lesion glycolysis and tumour-to-liver ratio, were used to determine the presence of metastases, and the results were compared with CT-determined LN metastasis. Receiver operating characteristic (ROC) curve analysis was used to determine the optimal cut-off values of the FDG PET parameters.@*RESULTS@#A total of 93 LNs were malignant, and 84 LNs were smaller than 10 mm. In all 165 LNs, an SUVmax of >2.51 showed a sensitivity of 73.1%, a specificity of 88.9%, and an accuracy of 80.0% in detecting metastatic LNs. CT showed a higher specificity (87.3%) and lower accuracy (65.5%). For non-enlarged regional LNs ( 2.4 showed a high sensitivity (91%) and accuracy (89%) in detecting metastasis in LNs ≥1 cm, and LNs < 1 cm with an SUVmax < 1.4 were likely to be benign.