Purpose: Although partial mesorectal excision (PME) and total mesorectal excision (TME) is primarily indicated for the upper and lower rectal cancer, respectively, few studies have evaluated whether PME or TME is more optimal for middle rectal cancer. Methods: This study included 671 patients with middle and upper rectal cancer who underwent robot-assisted PME or TME. The 2 groups were optimized by propensity score matching of sex, age, clinical stage, tumor location, and neoadjuvant treatment. Results: Complete mesorectal excision was achieved in 617 of 671 patients (92.0%), without showing a difference between the PME and TME groups. Local recurrence rate (5.3% vs. 4.3%, P>0.999) and systemic recurrence rate (8.5% vs. 16.0%, P=0.181) also did not differ between the 2 groups, in patients with middle and upper rectal cancer. The 5-year disease-free survival (81.4% vs. 74.0%, P=0.537) and overall survival (88.0% vs. 81.1%, P=0.847) also did not differ between the PME and TME groups, confined to middle rectal cancer. Moreover, 5-year recurrence and survival rates were not affected by distal resection margins of 2 cm (P=0.112) to 4 cm (P>0.999), regardless of pathological stages. Postoperative complication rate was higher in the TME than in the PME group (21.4% vs. 14.5%, P=0.027). Incontinence was independently associated with TME (odds ratio [OR], 2.009; 95% confidence interval, 1.015–3.975; P=0.045), along with older age (OR, 4.366, P<0.001) and prolonged operation time (OR, 2.196; P=0.500). Conclusion PME can be primarily recommended for patients with middle rectal cancer with lower margin of >5 cm from the anal verge.

Purpose: The use of gallium-68 prostate-specific membrane antigen-11 positron emission tomography/computed tomography (Ga-68 PSMA-11 PET/CT) is becoming increasingly common among men with prostate cancer (PCa). However, it remains uncertain which patients will derive the most benefit, and there is a scarcity of real-world data regarding its impact on altering treatment plans. This study investigated which patients would most benefit from Ga-68 PSMA-11 PET/CT, focusing on detection rates and changes in treatment strategies, drawing from a single-center experience. Materials and Methods: In total, 230 men with PCa who underwent Ga-68 PSMA-11 PET/CT between November 2021 and August 2022 were included in this retrospective study. The patients were classified into 5 groups based on their disease status: group 1, further work-up for high-risk localized PCa; group 2, de novo metastatic PCa; group 3, biochemical recurrence after definitive treatment; group 4, castration-resistant PCa; group 5, others. The positivity rate, positive lesions, predictive value of lymph node metastases, comparison with conventional images, and treatment changes after Ga-68 PSMA-11 PET/CT were analyzed in each group. Results: Of the 230 patients, 40 (17.4%), 20 (8.7%), 77 (33.5%), 76 (33.0%), and 17 (7.4%) were classified into groups 1–5, respectively. Ga-68 PSMA-11 PET/CT showed lesions in 74.8% of patients, and the optimal cutoff value for PSA was 1.99 ng/mL. Lesions not observed on conventional imaging were found in 62 patients (33.2%). In 38 patients (13.5%), treatment was changed due to Ga-68 PSMA-11 PET/CT. Conclusions These real-world data suggest that Ga-68 PSMA-11 PET/CT may be clinically useful for various disease conditions, as substantial stage migration and subsequent treatment changes occur in men with PCa. However, the prognostic impact of this modality remains unclear; thus, a well-designed prospective study is needed to address this issue.

Purpose: This study was designed to determine the feasibility of preoperative chemoradiotherapy (PCRT) in patients with clinical T2N0 distal rectal cancer. Methods: Patients who underwent surgery for clinical T2N0 distal rectal cancer between January 2008 and December 2016 were included. Patients were divided into PCRT and non-PCRT groups. Non-PCRT patients underwent radical resection or local excision (LE) according to the surgeon’s decision, and PCRT patients underwent surgery according to the response to PCRT. Patients received 50.0 to 50.4 gray of preoperative radiotherapy with concurrent chemotherapy. Results: Of 127 patients enrolled, 46 underwent PCRT and 81 did not. The mean distance of lesions from the anal verge was lower in the PCRT group (P=0.004). The most frequent operation was transanal excision and ultralow anterior resection in the PCRT and non-PCRT groups, respectively. Of the 46 patients who underwent PCRT, 21 (45.7%) achieved pathologic complete response, including 15 of the 24 (62.5%) who underwent LE. Rectal sparing rate was significantly higher in the PCRT group (11.1% vs. 52.2%, P<0.001). There were no significant differences in 3- and 5-year overall survival and recurrence-free survival regardless of PCRT or surgical procedures. Conclusion PCRT in clinical T2N0 distal rectal cancer patients increased the rectal sparing rate via LE and showed acceptable oncologic outcomes. PCRT may be a feasible therapeutic option to avoid abdominoperineal resection in clinical T2N0 distal rectal cancer.

Purpose: This study aimed to evaluate the predictive value of lymph node yield (LNY) for survival outcomes according to tumor response after preoperative chemoradiotherapy (PCRT) in patients with rectal cancer. Methods: This study was a retrospective study conducted in a tertiary center. A total of 1,240 patients with clinical stage II or III rectal cancer who underwent curative resection after PCRT between 2007 and 2016 were included. Patients were categorized into the good response group (tumor regression grade [TRG], 0–1) or poor response group (TRG, 2–3). Propensity score matching was performed for age, sex, and pathologic stage between LNY of ≥12 and LNY of <12 within tumor response group. The primary outcome was 5-year disease-free survival (DFS) and overall survival (OS). Results: LNY and positive lymph nodes were inversely correlated with TRG. In good responders, 5-year DFS and 5-year OS of patients with LNY of <12 were better than those with LNY of ≥12, but there was no statistical significance. In poor responders, the LNY of <12 group had worse survival outcomes than the LNY of ≥12 group, but there was also no statistical significance. LNY of ≥12 was not associated with DFS and OS in multivariate analysis. Conclusion LNY of <12 showed contrasting outcomes between the good and poor responders in 5-year DFS and OS. LNY of 12 may not imply adequate oncologic surgery or proper staging in rectal cancer patients treated by PCRT. Furthermore, a decrease in LNY should be comprehended differently according to tumor response.

Yolk sac tumors (YSTs), which are also called endodermal sinus tumors, are malignant tumors of germ cell origin. These tumors usually occur in the gonads, but 20% of cases have been reported at extragonadal sites. The head and neck is a rarely affected region that accounts for just 1% of all malignant tumors of germ cell origin. In addition, YSTs arise mostly in childhood. We present a rare pathologically pure case of primary adult YST in the sinonasal area. A 45-year-old male patient presented with a rapidly growing mass in the nasal cavity, which caused nasal obstruction and bloody post-nasal drip. The histopathologic features indicated pure YST, and immunohistochemical analysis revealed positive reactivity for Sal-like protein 4 and alpha-fetoprotein. Herein, we discuss the clinical, radiologic, and histologic features of this YST and review other cases of sinonasal YST in adults.

Purpose: This study aims to oncologic outcomes of the watch-and-wait (WW) strategy compared with radical resection (RR). Methods: Patients with rectal cancer who received neoadjuvant chemoradiotherapy (nCRT) and achieved ≤ycT2 between 2008 and 2016 were included. The mean follow-up time was 61 months (range, 0–168 months). Recurrence-free survival (RFS), local recurrence-free survival (LRFS), distant metastasis-free survival (DMFS), and overall survival (OS) were compared. A total of 446 patients were included, and WW was adopted for 34 patients. Results: WW patients were older (P = 0.022) and less advanced initial cT stage (P = 0.004). Ten patients in the WW group (29.4%) experienced local regrowth. Later, distant metastases occurred in 7 of these patients. The 5-year RFS (74.1% vs. 79.5%), DMFS (74.1% vs. 81.6%), and OS (90.4% vs. 87.7%) for the WW and RR groups were not statistically different.However, LRFS in the WW group was significantly lower (65.1% vs. 97.0%, P < 0.001). The initial cT stage was associated with RFS (P = 0.019) and LRFS (P = 0.037). WW was an independent risk factor for LRFS (P < 0.001) and DMFS (P = 0.024).After 1:4 propensity score matching between the WW and RR groups, there was no difference in RFS and OS. However, the 5-year LRFS (67.5% vs. 96.5%) and DMFS (73.2% vs. 86.4%) demonstrated a statistically significant difference between the groups. Conclusion By appointing the WW strategy, oncologic safety was not ensured. The WW strategy must be implemented with caution in patients with ≤ycT2 stage, particularly those with advanced initial cT stage.

Background/Aims: The prospective Crohn’s Disease Clinical Network and Cohort Study is a nationwide multicenter cohort study of patients with Crohn’s disease (CD) in Korea, aiming to prospectively investigate the clinical features and long-term prognosis associated with CD. Methods: Patients diagnosed with CD between January 2009 and September 2019 were prospectively enrolled. They were divided into two cohorts according to the year of diagnosis: cohort 1 (diagnosed between 2009 and 2011) versus cohort 2 (between 2012 and 2019). Results: A total of 1,175 patients were included, and the median follow-up duration was 68 months (interquartile range, 39.0 to 91.0 months). The treatment-free durations for thiopurines (p<0.001) and anti-tumor necrosis factor agents (p=0.018) of cohort 2 were shorter than those of cohort 1. Among 887 patients with B1 behavior at diagnosis, 149 patients (16.8%) progressed to either B2 or B3 behavior during follow-up. Early use of thiopurine was associated with a reduced risk of behavioral progression (adjusted hazard ratio [aHR], 0.69; 95% confidence interval [CI], 0.50 to 0.90), and family history of inflammatory bowel disease was associated with an increased risk of behavioral progression (aHR, 2.29; 95% CI, 1.16 to 4.50). One hundred forty-one patients (12.0%) underwent intestinal resection, and the intestinal resection-free survival time was significantly longer in cohort 2 than in cohort 1 (p=0.003). The early use of thiopurines (aHR, 0.35;95% CI, 0.23 to 0.51) was independently associated with a reduced risk of intestinal resection. Conclusions The prognosis of CD in Korea appears to have improved over time, as evidenced by the decreasing intestinal resection rate. Early use of thiopurines was associated with an improved prognosis represented by a reduced risk of intestinal resection.

Purpose: The purpose of this study was to evaluate the effects of mouthwash containing sodium chloride on dental plaque, gingival inflammation index, and bad breath through clinical trials. Materials and Methods: This trial was designed as 12 weeks and subjects were instructed to put an appropriate amount of the provided standard detergent on a toothbrush and brush their teeth 3 times a day. They were instructed to gargle a mouthwash provided to each group after brushiung. Efficacy was evaluated by performing gingival and periodontal-related index tests, dental plaque changes, and bad breath tests a total of 5 times. All data were statistically analyzed using 2-sample t-test, paired t-test to compare between groups at 95% significance level using IBM SPSS Statistics 24.0. Results: As a result of the PMA index measurement, the gingivitis improvement effect rate of the experimental group compared to the control group was 107.63% after 8 weeks and 73.08% after 12 weeks. As a result of the PHP index measurement, the plaque improvement effect rate of the experimental group compared to the control group was 79.37% after 8 weeks and 74.06% after 12weeks. As a result of measuring volatile sulfur compounds using Oral Chroma, the effectiveness of improvement in bad breath in the experimental group was 65.06% after 8 weeks and 99.33% after 12 weeks, compared to the control group. Conclusion As a result of this study, it was confirmed that effective gingivitis alleviation, plaque removal effect and bad breath removal effect can be expected when a mouthwash containing sodium chloride, green tea extract, and sodium monofluorophosphate is used.

Purpose: Carcinoma arising from Crohn disease (CD) is rare, and there is no clear guidance on how to properly screen for at-risk patients and choose appropriate care. This study aimed to evaluate the clinicopathological characteristics, treatment, and oncologic outcomes of CD patients diagnosed with colorectal cancer (CRC). Methods: Using medical records, we retrospectively enrolled a single-center cohort of 823 patients who underwent abdominal surgery for CD between January 2006 and December 2015. CD-associated CRC patients included those with adenocarcinoma, lymphoma, or neuroendocrine tumors of the colon and rectum. Results: Nineteen patients (2.3%) underwent abdominal surgery to treat CD-associated CRC. The mean duration of CD in the CD-associated CRC group was significantly longer than that in the benign CD group (124.7 ± 77.7 months vs. 68.9 ± 60.2 months, P = 0.006). The CD-associated CRC group included a higher proportion of patients with a history of perianal disease (73.7% vs. 50.2%, P = 0.035) and colonic location (47.4% vs. 6.5%, P = 0.001). Among 19 CD-associated CRC patients, 17 (89.5%) were diagnosed with adenocarcinoma, and of the 17 cases, 15 (88.2%) were rectal adenocarcinoma. On multivariable analyses for developing CRC, only colonic location was a risk factor (relative risk, 7.735; 95% confidence interval, 2.862–20.903; P = 0.001). Conclusion Colorectal malignancy is rare among CD patients, even among patients who undergo abdominal surgery. Rectal adenocarcinoma accounted for most of the CRC, and colonic location was a risk factor for developing CRC.