Gastric cancer is one of the most common cancers in Korea and the world. Since 2004, this is the 4th gastric cancer guideline published in Korea which is the revised version of previous evidence-based approach in 2018. Current guideline is a collaborative work of the interdisciplinary working group including experts in the field of gastric surgery, gastroenterology, endoscopy, medical oncology, abdominal radiology, pathology, nuclear medicine, radiation oncology and guideline development methodology. Total of 33 key questions were updated or proposed after a collaborative review by the working group and 40 statements were developed according to the systematic review using the MEDLINE, Embase, Cochrane Library and KoreaMed database. The level of evidence and the grading of recommendations were categorized according to the Grading of Recommendations, Assessment, Development and Evaluation proposition. Evidence level, benefit, harm, and clinical applicability was considered as the significant factors for recommendation. The working group reviewed recommendations and discussed for consensus. In the earlier part, general consideration discusses screening, diagnosis and staging of endoscopy, pathology, radiology, and nuclear medicine. Flowchart is depicted with statements which is supported by meta-analysis and references. Since clinical trial and systematic review was not suitable for postoperative oncologic and nutritional follow-up, working group agreed to conduct a nationwide survey investigating the clinical practice of all tertiary or general hospitals in Korea. The purpose of this survey was to provide baseline information on follow up. Herein we present a multidisciplinary-evidence based gastric cancer guideline.

Background/Aims: Although the use of surveillance 18F-fluorodeoxyglucose (FDG) positron emission tomography/computed tomography (PET/CT) is discouraged in patients with diffuse large B-cell lymphoma, its usefulness in different subtypes has not been thoroughly investigated. Methods: We retrospectively evaluated 157 patients who showed positive results on surveillance FDG-PET/CT every 6 months following complete response for up to 5 years. All of the patients also underwent biopsies. Results: Seventy-eight (49.6%) of 157 patients had true positive results; the remaining 79 (50.3%), including eight (5.1%) with secondary malignancies, were confirmed to yield false positive results. Among the 78 patients with true positive results, the disease in seven (8.9%) had transformed to a different subtype. The positive predictive value (PPV) of FDG-PET/CT for aggressive B-cell non-Hodgkin’s lymphoma (NHL) was lower than that for indolent B-cell or aggressive T-cell NHL (p = 0.003 and p = 0.018, respectively), especially in patients with a low/low-intermediate international prognostic index (IPI) upon a positive PET/CT finding. On the other hand, indolent B-cell and aggressive T-cell NHL patients showed PPVs of > 60%, including those with low/low-intermediate secondary IPIs. Conclusions The role of FDG-PET/CT surveillance is limited, and differs according to the lymphoma subtype. FDG-PET/CT may be useful in detecting early relapse in patients with aggressive T-cell NHL, including those with low/low-intermediate risk secondary IPI; as already known, FDG-PET/CT has no role in aggressive B-cell NHL. Repeat biopsy should be performed to discriminate relapse or transformation from false positive findings in patients with positive surveillance FDG-PET/CT results.

Purpose: We aimed to compare different reference regions and select one with the most clinical relevance on C11-acetate (ACE) positron emission tomography/computed tomography (PET/CT) in patients with cerebral glioma. Methods: We retrospectively reviewed 51 patients with cerebral glioma who underwent baseline ACE PET/CT at diagnosis.Other than the standardized uptake value (SUV) of the primary tumor, SUVs of the reference regions including the normal gray matter, white matter, choroid plexus, and cerebellum were measured. Then, the SUV ratio (SUVR = tumor SUV max /reference region SUV mean ) was calculated. The effect of patient age on the SUV mean of each reference was examined and the SUVRs of each reference region were compared between grades. age, sex, tumor size, histological grades, SUVR , and the presence of isocitrate dehydrogenase (IDH) mutation were included for survival analyses. Results: Except for the cerebellum showing a mild negative correlation, we found no correlations between age and SUV mean using the gray matter, white matter, and choroid plexus (r = − 0.280, P < = 0.047). Only the SUVR -choroid plexus was able to differentiate between the WHO grades (Grade II vs. III, P < = 0.035; grade III vs. IV, P < < 0.001; grade II vs. IV, P < 0.001). Multivariate Cox proportional hazards models found that the SUVR-choroid plexus and IDH mutation were statistically significant for predicting OS. Conclusion Of the different reference regions used for grading cerebral gliomas, the choroid plexus was found to be the most optimal.In addition, the SUV ratio is useful to predict the overall survival in the model with the choroid plexus as a reference region.

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.
Electrons ; Follow-Up Studies ; Glycolysis ; Humans ; Lymph Nodes ; Melanoma ; Neoplasm Metastasis ; Positron-Emission Tomography and Computed Tomography ; Recurrence ; ROC Curve ; Sensitivity and Specificity

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.

Lung cancer is one of the leading causes of death worldwide. There are 2 major subtypes of lung cancer, non-small-cell lung cancer (NSCLC) and small-cell lung cancer (SCLC). Studies show that NSCLC is the more prevalent type of lung cancer that accounts for approximately 80%–85% of cases. Although, various treatment methods, such as chemotherapy, surgery, and radiation therapy have been used to treat lung cancer patients, there is an emergent need to develop more effective approaches to deal with advanced stages of tumors. Recently, immunotherapy has emerged as a new approach to combat with such tumors. The development and success of programmed cell death 1 (PD-1)/program death-ligand 1 (PD-L1) inhibitors and cytotoxic T-lymphocyte antigen 4 (CTLA-4) blockades in treating metastatic cancers opens a new pavement for the future research. The current mini review discusses the significance of immune checkpoint inhibitors in promoting the death of tumor cells. Additionally, this review also addresses the importance of tumor-specific antigens (neoantigens) in the development of cancer vaccines and major challenges associated with this therapy. Immunotherapy can be a promising approach to treat NSCLC because it stimulates host's own immune system to recognize cancer cells. Therefore, future research should focus on the development of new methodologies to identify novel checkpoint inhibitors and potential neoantigens.
Cancer Vaccines ; Cause of Death ; Cell Death ; CTLA-4 Antigen ; Drug Therapy ; Humans ; Immune System ; Immunotherapy* ; Lung Neoplasms* ; Lung*

PURPOSE: Parathyroid adenoma detection with dual-phase (99m)Tc-sestamibi (MIBI) scintigraphy depends on differential MIBI washout from thyroid. However, autoimmune thyroid disease (AITD) may cause MIBI to be retained in the thyroid gland and reduce parathyroid detection.We evaluated the impact of AITD on MIBI thyroid retention and additional benefit of SPECT/CT in these patients.METHODS: Dual phase planar MIBI and SPECT/CT was performed on 82 patients. SPECT/CTwas performed immediatelyafter delayed planar scan. Thyroid density (Hounsfield unit, CT-HU) and size were measured on CT component of SPECT/CT. MIBI uptake in early scans and retention in delayed scans were visually graded and correlated with clinical factors and CT findings. Finally, planar and SPECT/CT findings were compared for parathyroid lesion visualization according to thyroid MIBI retention.RESULTS: In early scan, multivariate analysis showed only thyroid size predicted early uptake. In delayed scan, multivariate analysis showed higher visual grade in early scan, lower CTHU or AITD were significant predictors for delayed thyroid parenchymal retention. Overall, ten more parathyroid lesions were visualized on SPECT/CT compared to planar scans (57 vs. 47, p = 0.002). SPECT/CT was especially more useful in patients with thyroidal MIBI retention, as eight out of the ten additional lesions detected were found in patients with thyroid MIBI retention.CONCLUSION: AITD is an important factor for MIBI thyroid parenchymal retention on delayed scans, and may impede parathyroid lesion detection. Patients with MIBI retention in the thyroid parenchyma on delayed scans are likely to benefit from an additional SPECT/CT.
Humans ; Multivariate Analysis ; Parathyroid Neoplasms ; Radionuclide Imaging ; Thyroid Diseases ; Thyroid Gland

OBJECTIVES: To evaluate the prognostic impact of ultrasonography (US) features and 18F-fluorodeoxyglucose (18F-FDG) uptake in patients with papillary thyroid microcarcinoma (PTMC). METHODS: This study included 74 patients with a single PTMC diagnosed pathologically. Patients underwent total thyroidectomy, or near-total thyroidectomy and staging thyroid US and positron emission tomography (PET) were performed prior to surgery. US features of thyroid nodules were reviewed retrospectively and the maximum standard uptake value (SUV) of nodules was semiquantitatively analyzed on 18F-FDG PET/computed tomography (CT). Patients were followed-up for recurrence, which was defined as PTC on cytology results, elevated serum thyroglobulin (Tg) or anti-Tg antibody levels, or uptake on whole-body scintigraphy. We used univariate and multivariate analyses to evaluate whether poor prognostic outcomes were associated with US features or SUV values derived from PET/CT of nodules. In addition, subjects were divided into 2 groups for subgroup analyses: one with nodules equal to or larger than 5 mm and one with nodules smaller than 5 mm. RESULTS: Among the 74 patients, there was no recurrence. Thus we evaluated the correlation between SUV value and US features with poor prognostic factors of PTMC which included extrathyroid extension, central and lateral lymph node (LN) metastasis. However no clinicopathologic factors were associated with extrathyroid extension, central LN metastasis, or lateral LN metastasis. CONCLUSION: In patients with PTMC, US features and SUV values on FDG-PET were not related to extrathyroid extension or LN metastasis. However, future studies with a larger sample size and longer follow-up should be performed to verify the results of this study.
Fluorodeoxyglucose F18 ; Follow-Up Studies ; Humans ; Lymph Nodes ; Multivariate Analysis ; Neoplasm Metastasis ; Positron-Emission Tomography ; Positron-Emission Tomography and Computed Tomography ; Radionuclide Imaging ; Recurrence ; Retrospective Studies ; Sample Size ; Thyroglobulin ; Thyroid Gland* ; Thyroid Nodule ; Thyroidectomy ; Ultrasonography*

von Hippel-Lindau (VHL) disease is an autosomal dominant inherited tumor syndrome associated with mutations of the VHL tumor suppressor gene located on chromosome 3p25. The loss of functional VHL protein contributes to tumorigenesis. This condition is characterized by development of benign and malignant tumors in the central nervous system (CNS) and the internal organs, including kidney, adrenal gland, and pancreas. We herein describe the case of a 74-year-old man carrying the VHL gene mutation who was affected by simultaneous colorectal adenocarcinoma, renal clear cell carcinoma, and hemangioblastomas of CNS.
Adenocarcinoma* ; Adrenal Glands ; Aged ; Carcinogenesis ; Carcinoma, Renal Cell* ; Central Nervous System ; Colorectal Neoplasms ; Genes, Tumor Suppressor ; Hemangioblastoma* ; Humans ; Kidney ; Pancreas ; von Hippel-Lindau Disease*