Purpose: This study aims to evaluate the treatment approaches and locoregional patterns for adenoid cystic carcinoma (ACC) in the breast, which is an uncommon malignant tumor with limited clinical data. Materials and Methods: A total of 93 patients diagnosed with primary ACC in the breast between 1992 and 2022 were collected from multi-institutions. All patients underwent surgical resection, including breast-conserving surgery (BCS) or total mastectomy (TM). Recurrence patterns and locoregional recurrence-free survival (LRFS) were assessed. Results: Seventy-five patients (80.7%) underwent BCS, and 71 of them (94.7%) received post-operative radiation therapy (PORT). Eighteen patients (19.3%) underwent TM, with five of them (27.8%) also receiving PORT. With a median follow-up of 50 months, the LRFS rate was 84.2% at 5 years. Local recurrence (LR) was observed in five patients (5.4%) and four cases (80%) of the LR occurred in the tumor bed. Three of LR (3/75, 4.0%) had a history of BCS and PORT, meanwhile, two of LR (2/18, 11.1%) had a history of mastectomy. Regional recurrence occurred in two patients (2.2%), and both cases had a history of PORT with (n=1) and without (n=1) irradiation of the regional lymph nodes. Partial breast irradiation (p=0.35), BCS (p=0.96) and PORT in BCS group (p=0.33) had no significant association with LRFS. Conclusion BCS followed by PORT was the predominant treatment approach for ACC of the breast and LR mostly occurred in the tumor bed. The findings of this study suggest that partial breast irradiation might be considered for PORT in primary breast ACC.

Purpose: This study aims to evaluate the treatment approaches and locoregional patterns for adenoid cystic carcinoma (ACC) in the breast, which is an uncommon malignant tumor with limited clinical data. Materials and Methods: A total of 93 patients diagnosed with primary ACC in the breast between 1992 and 2022 were collected from multi-institutions. All patients underwent surgical resection, including breast-conserving surgery (BCS) or total mastectomy (TM). Recurrence patterns and locoregional recurrence-free survival (LRFS) were assessed. Results: Seventy-five patients (80.7%) underwent BCS, and 71 of them (94.7%) received post-operative radiation therapy (PORT). Eighteen patients (19.3%) underwent TM, with five of them (27.8%) also receiving PORT. With a median follow-up of 50 months, the LRFS rate was 84.2% at 5 years. Local recurrence (LR) was observed in five patients (5.4%) and four cases (80%) of the LR occurred in the tumor bed. Three of LR (3/75, 4.0%) had a history of BCS and PORT, meanwhile, two of LR (2/18, 11.1%) had a history of mastectomy. Regional recurrence occurred in two patients (2.2%), and both cases had a history of PORT with (n=1) and without (n=1) irradiation of the regional lymph nodes. Partial breast irradiation (p=0.35), BCS (p=0.96) and PORT in BCS group (p=0.33) had no significant association with LRFS. Conclusion BCS followed by PORT was the predominant treatment approach for ACC of the breast and LR mostly occurred in the tumor bed. The findings of this study suggest that partial breast irradiation might be considered for PORT in primary breast ACC.

Purpose: This study aims to evaluate the treatment approaches and locoregional patterns for adenoid cystic carcinoma (ACC) in the breast, which is an uncommon malignant tumor with limited clinical data. Materials and Methods: A total of 93 patients diagnosed with primary ACC in the breast between 1992 and 2022 were collected from multi-institutions. All patients underwent surgical resection, including breast-conserving surgery (BCS) or total mastectomy (TM). Recurrence patterns and locoregional recurrence-free survival (LRFS) were assessed. Results: Seventy-five patients (80.7%) underwent BCS, and 71 of them (94.7%) received post-operative radiation therapy (PORT). Eighteen patients (19.3%) underwent TM, with five of them (27.8%) also receiving PORT. With a median follow-up of 50 months, the LRFS rate was 84.2% at 5 years. Local recurrence (LR) was observed in five patients (5.4%) and four cases (80%) of the LR occurred in the tumor bed. Three of LR (3/75, 4.0%) had a history of BCS and PORT, meanwhile, two of LR (2/18, 11.1%) had a history of mastectomy. Regional recurrence occurred in two patients (2.2%), and both cases had a history of PORT with (n=1) and without (n=1) irradiation of the regional lymph nodes. Partial breast irradiation (p=0.35), BCS (p=0.96) and PORT in BCS group (p=0.33) had no significant association with LRFS. Conclusion BCS followed by PORT was the predominant treatment approach for ACC of the breast and LR mostly occurred in the tumor bed. The findings of this study suggest that partial breast irradiation might be considered for PORT in primary breast ACC.

Purpose: Perspectives of radiation oncologists on oligometastatic disease was investigated using multi-layered survey. Materials and Methods: Online survey on the oligometastatic disease was distributed to the board-certified regular members of the Korean Society for Radiation Oncology. The questionnaire consisted of four domains: five questions on demographics; five on the definition of oligometastatic disease; four on the role of local therapy; and three on the oligometastatic disease classification, respectively. Results: A total of 135 radiation oncologists participated in the survey. The median length of practice after board certification was 22.5 years (range, 1 to 44 years), and the vast majority (94.1%) answered affirmatively to the clinical experience in oligometastatic disease management. Nearly two-thirds of the respondents considered the number of involved organs as an independent factor in defining oligometastasis. Most frequently perceived upper limit on the numerical definition of oligometastasis was 5 (64.2%), followed by 3 (26.0%), respectively. Peritoneal and brain metastasis were nominated as the sites to be excluded from oligometastastic disease by 56.3% and 12.6% of the participants, respectively. Vast majority (82.1%) agreed on the role of local treatment in the management of oligometastatic disease. Majority (72%) of the participants acknowledged the European Society for Radiotherapy and Oncology (ESTRO)–European Organisation for Research and Treatment of Cancer (EORTC) classification of oligometastatic disease, however, only 43.3% answered that they applied this classification in their clinical practice. Underlying reasons against the clinical use were ‘too complicated’ (66.0%), followed by ‘insufficient supporting evidence’ (30.0%), respectively. Conclusion While most radiation oncologists supported the role of local therapy in oligometastatic disease, there were several inconsistencies in defining and categorizing oligometastatic disease. Continued education and training on oligometastatic disease would be also required to build consensus among participating caregivers.

Purpose: Risk factors predicting distant metastasis (DM) in extrahepatic bile duct cancer (EHBDC) patients treated with curative resection were investigated. Materials and Methods: Medical records of 1,418 EHBDC patients undergoing curative resection between Jan 2000 and Dec 2015 from 14 institutions were reviewed. After resection, 924 patients (67.6%) were surveilled without adjuvant therapy, 297 (21.7%) were treated with concurrent chemoradiotherapy (CCRT) and 148 (10.8%) with CCRT followed by chemotherapy. To exclude the treatment effect from innate confounders, patients not treated with adjuvant therapy were evaluated. Results: After a median follow-up of 36.7 months (range, 2.7 to 213.2 months), the 5-year distant metastasis-free survival (DMFS) rate was 57.7%. On multivariate analysis, perihilar or diffuse tumor (hazard ratio [HR], 1.391; p=0.004), poorly differentiated histology (HR, 2.014; p < 0.001), presence of perineural invasion (HR, 1.768; p < 0.001), positive nodal metastasis (HR, 2.670; p < 0.001) and preoperative carbohydrate antigen (CA) 19-9 ≥ 37 U/mL (HR, 1.353; p < 0.001) were significantly associated with inferior DMFS. The DMFS rates significantly differed according to the number of these risk factors. For validation, patients who underwent adjuvant therapy were evaluated. In patients with ≥ 3 factors, additional chemotherapy after CCRT resulted in a superior DMFS compared with CCRT alone (5-year rate, 47.6% vs. 27.7%; p=0.001), but the benefit of additional chemotherapy was not observed in patients with 0-2 risk factors. Conclusion Tumor location, histologic differentiation, perineural invasion, lymph node metastasis, and preoperative CA 19-9 level predicted DM risk in resected EHBDC. These risk factors might help identifying a subset of patients who could benefit from additional chemotherapy after resection.

Differentiated thyroid cancer demonstrates a wide range of clinical presentations, from very indolent cases to those with an aggressive prognosis. Therefore, diagnosing and treating each cancer appropriately based on its risk status is important. The Korean Thyroid Association (KTA) has provided and amended the clinical guidelines for thyroid cancer management since 2007. The main changes in this revised 2024 guideline include 1) individualization of surgical extent according to pathological tests and clinical findings, 2) application of active surveillance in low-risk papillary thyroid microcarcinoma, 3) indications for minimally invasive surgery, 4) adoption of World Health Organization pathological diagnostic criteria and definition of terminology in Korean, 5) update on literature evidence of recurrence risk for initial risk stratification, 6) addition of the role of molecular testing, 7) addition of definition of initial risk stratification and targeting thyroid stimulating hormone (TSH) concentrations according to ongoing risk stratification (ORS), 8) addition of treatment of perioperative hypoparathyroidism, 9) update on systemic chemotherapy, and 10) addition of treatment for pediatric patients with thyroid cancer.

Purpose: Despite numerous studies on the optimal treatments for oligometastatic disease (OMD), there is no established interdisciplinary consensus on its diagnosis or classification. This survey-based study aimed to analyze the differential opinions of colorectal surgeons and radiation oncologists regarding the definition and treatment of OMD from the colorectal primary. Materials and Methods: A total of 141 participants were included in this study, consisting of 63 radiation oncologists (44.7%) and 78 colorectal surgeons (55.3%). The survey consisted of 19 questions related to OMD, and the responses were analyzed using the chi-square test to determine statistical differences between the specialties. Results: The radiation oncologists chose “bone” more frequently compared to the colorectal surgeons (19.2% vs. 36.5%, p=0.022), while colorectal surgeons favored “peritoneal seeding” (26.9% vs. 9.5%, p=0.009). Regarding the number of metastatic tumors, 48.3% of colorectal surgeons responded that “irrelevant, if all metastatic lesions are amendable to local therapy”, while only 21.8% of radiation oncologist chose same answer. When asked about molecular diagnosis, most surgeons (74.8%) said it was important, but only 35.8% of radiation oncologists agreed. Conclusion This study demonstrates that although radiation oncologists and colorectal surgeons agreed on a majority of aspects such as diagnostic imaging, biomarker, systemic therapy, and optimal timing of OMD, they also had quite different perspectives on several aspects of OMD. Understanding these differences is crucial to achieving multidisciplinary consensus on the definition and optimal management of OMD.

Purpose: To investigate the prognostic value of the neutrophil to lymphocyte ratio (NLR) and platelet to lymphocyte ratio (PLR) in patients with hepatocellular carcinoma (HCC) treated with stereotactic body radiotherapy (SBRT). Methods: The medical records of HCC patients treated with SBRT between 2008 and 2019 were reviewed retrospectively. The NLR and PLR were calculated from the serum complete blood count before and after SBRT, and the prognostic values of the NLR and PLR for the treatment outcomes were evaluated. Results: Thirty-nine patients with 49 HCC lesions were included. After a median follow-up of 26.8 months (range, 8.4-80.0 months), three-year local control, overall survival (OS), and progression-free survival (PFS) rate were 97.4%, 78.3%, and 35.2%, respectively.Both NLR and PLR increased significantly after SBRT and decreased slowly to the pre-SBRT value at 6 months. Univariable analysis showed that gross tumor volume (GTV) >14 cc, post-SBRT PLR >90, and PLR change >30 were associated with a poorer OS (p=0.002, p=0.011, and p=0.001, respectively), and the PLR change was significant in multivariable analysis (hazard ratio [HR], 10.09; 95% CI, 1.15-88.40; p=0.037). For PFS, GTV >14 cc, post-SBRT NLR >2.5 and post-SBRT PLR >90 were predictive of a poorer PFS in univariable analysis (p=0.011, p=0.004 and p=0.041, respectively) and only post-SBRT NLR >2.5 remained significant in multivariable analysis (HR, 2.44; 95% CI, 1.03-5.76; p=0.042, respectively). Conclusions The NLR and PLR increased transiently after SBRT, and the post-SBRT NLR and PLR were associated with the clinical outcomes of HCC patients.

Background: Conventional diagnostic approaches for adrenal tumors require multi-step processes, including imaging studies and dynamic hormone tests. Therefore, this study aimed to discriminate adrenal tumors from a single blood sample based on the combination of liquid chromatography-mass spectrometry (LC-MS) and machine learning algorithms in serum profiling of adrenal steroids. Methods: The LC-MS-based steroid profiling was applied to serum samples obtained from patients with nonfunctioning adenoma (NFA, n=73), Cushing’s syndrome (CS, n=30), and primary aldosteronism (PA, n=40) in a prospective multicenter study of adrenal disease. The decision tree (DT), random forest (RF), and extreme gradient boost (XGBoost) were performed to categorize the subtypes of adrenal tumors. Results: The CS group showed higher serum levels of 11-deoxycortisol than the NFA group, and increased levels of tetrahydrocortisone (THE), 20α-dihydrocortisol, and 6β-hydroxycortisol were found in the PA group. However, the CS group showed lower levels of dehydroepiandrosterone (DHEA) and its sulfate derivative (DHEA-S) than both the NFA and PA groups. Patients with PA expressed higher serum 18-hydroxycortisol and DHEA but lower THE than NFA patients. The balanced accuracies of DT, RF, and XGBoost for classifying each type were 78%, 96%, and 97%, respectively. In receiver operating characteristics (ROC) analysis for CS, XGBoost, and RF showed a significantly greater diagnostic power than the DT. However, in ROC analysis for PA, only RF exhibited better diagnostic performance than DT. Conclusion The combination of LC-MS-based steroid profiling with machine learning algorithms could be a promising one-step diagnostic approach for the classification of adrenal tumor subtypes.

Ceramides are associated with metabolic complications including diabetic nephropathy in patients with diabetes. Recent studies have reported that podocytes play a pivotal role in the progression of diabetic nephropathy. Also, mitochondrial dysfunction is known to be an early event in podocyte injury. Thus, we tested the hypothesis that ceramide accumulation in podocytes induces mitochondrial damage through reactive oxygen species (ROS) production in patients with diabetic nephropathy.