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Objective:. We explored the oncological impact of tumor deposits (TDs) on colon cancer and proposed optimal modifications to the current staging system. Background:. In the existing American Joint Committee on Cancer colon cancer staging system, TDs are incorporated into the N category as N1c. When lymph node metastases (LNMs) are present, their number is considered to determine nodal stages, such as N1a/b or N2a/b, regardless of TDs. Methods:. 4212 patients with primary colon cancer who underwent surgical resection in the Seoul Colorectal Group (2010–2020) and 93,057 patients from the Surveillance, Epidemiology, and End Results*Stat database (2000–2017) were included in this study. Patients were classified according to the number of metastatic lymph nodes (LNs) (0/1–3/≥4) and the presence of TDs. Results:. TDs were significantly associated with left colon cancer, a higher T category, and vascular/perineural invasion. Patients with TDs had higher recurrence rates (23.1 vs 7.5%, P < 0.001). The TD-positive patients had notably worse overall survival (OS) and recurrence-free survival rates. The survival outcomes of TD-positive patients without LNM were inferior to those of TD-negative patients with LN1–3 (5-year OS: 78.9 vs 87.8%, P = 0.04). The survival outcomes of TD-positive patients with LN1–3 were similar to those of TD-negative patients with LN ≥4 (5-year OS: 87.0 vs 77.1%, P = 0.11). Survival outcomes obtained using the Surveillance, Epidemiology, and End Results *Stat database yielded consistent results. Conclusions:. TDs were associated with poor prognostic factors and had a significant impact on survival outcomes. The incorporation of tumor deposits into nodal classifications beyond the current N1c criteria may improve the staging system and more accurately reflect the recurrence and survival rates among patients with colon cancer. TD-positive in N1a or N1b could be categorized as N2.

Identification of Helicotylenchus species is very challenging due to phenotypic plasticity and existence of cryptic species complexes. Recently, the use of rDNA barcodes has proven to be useful for identification of Helicotylenchus. Molecular markers are a quick diagnostic tool and are crucial for discriminating related species and resolving cryptic species complexes within this speciose genus. However, DNA barcoding is not an error-free approach. The public databases appear to be marred by incorrect sequences, arising from sequencing errors, mislabeling, and misidentifications. Herein, we provide a comprehensive analysis of the newly obtained, and published DNA sequences of Helicotylenchus, revealing the potential faults in the available DNA barcodes. A total of 97 sequences (25 nearly full-length 18S-rRNA, 12 partial 28S-rRNA, 16 partial internal transcribed spacer [ITS]-rRNA, and 44 partial cytochrome c oxidase subunit I [COI] gene sequences) were newly obtained in the present study. Phylogenetic relationships between species are given as inferred from the analyses of 103 sequences of 18S-rRNA, 469 sequences of 28S-rRNA, 183 sequences of ITS-rRNA, and 63 sequences of COI. Remarks on suggested corrections of published accessions in GenBank database are given. Additionally, COI gene sequences of H. dihystera, H. asiaticus and the contentious H. microlobus are provided herein for the first time. Similar to rDNA gene analyses, the COI sequences support the genetic distinctness and validity of H. microlobus. DNA barcodes from type material are needed for resolving the taxonomic status of the unresolved taxonomic groups within the genus.

Purpose This study aimed to evaluate the long-term clinical outcomes based on the ligation level of the inferior mesenteric artery (IMA) in patients with rectal cancer. Methods This was a retrospective analysis of a prospectively collected database that included all patients who underwent elective low anterior resection for rectal cancer between January 2013 and December 2019. The clinical outcomes included oncological outcomes, postoperative complications, and functional outcomes. The oncological outcomes included overall survival (OS) and relapse-free survival (RFS). The functional outcomes, including defecatory and urogenital functions, were analyzed using the Fecal Incontinence Severity Index, International Prostate Symptom Score, and International Index of Erectile Function questionnaires. Results In total, 545 patients were included in the analysis. Of these, 244 patients underwent high ligation (HL), whereas 301 underwent low ligation (LL). The tumor size was larger in the HL group than in the LL group. The number of harvested lymph nodes (LNs) was higher in the HL group than in the LL group. There were no significant differences in complication rates and recurrence patterns between the groups. There were no significant differences in 5-year RFS and OS between the groups. Cox regression analysis revealed that the ligation level (HL vs. LL) was not a significant risk factor for oncological outcomes. Regarding functional outcomes, the LL group showed a significant recovery in defecatory function 1 year postoperatively compared with the HL group. Conclusion LL with LNs dissection around the root of the IMA might not affect the oncologic outcomes comparing to HL; however, it has minimal benefit for defecatory function.

Purpose Most predictive factors for lymph node metastasis in rectal neuroendocrine tumors (NETs) have been based on local and endoscopic resection. We aimed to evaluate the risk factors for lymph node metastasis in patients who underwent radical resection for rectal NETs and stratify the risk of lymph node metastasis. Methods Sixty-four patients who underwent radical resection for rectal NETs between January 2001 and January 2018 were included. We investigated the risk factors of lymph node metastasis using clinicopathologic data. We also performed a risk stratification for lymph node metastases using the number of previously known risk factors. For oncologic outcomes, the 5-year overall survival and recurrence-free survival were evaluated in both groups. Results Among the patients who underwent radical surgery, 32 (50.0%) had lymph node metastasis and 32 (50.0%) had non–lymph node metastasis. In the multivariable analysis, only the male sex was identified as a risk factor for lymph node metastasis (odds ratio, 3.695; 95% confidence interval, 1.128–12.105; P=0.031). When there were 2 or more known risk factors, the lymph node metastasis rate was significantly higher than when there were one or no risk factors (odds ratio, 3.667; 95% confidence interval, 1.023–13.143; P=0.046). There was also no statistical difference between the 2 groups in 5-year overall survival (P=0.431) and 5-year recurrence-free survival (P=0.144). Conclusion We found that the rate of lymph node metastasis increased significantly when the number of known risk factors is 2 or more.

Purpose Minimally invasive surgery (MIS) is currently the standard treatment for rectal cancer. However, its limitations include complications and incomplete total mesorectal excision (TME) due to anatomical features and technical difficulties. Transanal TME (TaTME) has been practiced since 2010 to improve this, but there is a risk of local recurrence and intra-abdominal contamination. We aimed to analyze samples obtained through lavage to compare laparoscopic TME (LapTME) and TaTME. Methods From June 2020 to January 2021, 20 patients with rectal cancer undergoing MIS were consecutively and prospectively recruited. Samples were collected at the start of surgery, immediately after TME, and after irrigation. The samples were analyzed for carcinoembryonic antigen (CEA) and cytokeratin 20 (CK20) through a quantitative real-time polymerase chain reaction. The primary outcome was to compare the detected amounts of CEA and CK20 immediately after TME between the surgical methods. Results Among the 20 patients, 13 underwent LapTME and 7 underwent TaTME. Tumor location was lower in TaTME (7.3 cm vs. 4.6 cm, P=0.012), and negative mesorectal fascia (MRF) was more in LapTME (76.9% vs. 28.6%, P=0.044). CEA and CK20 levels were high in 3 patients (42.9%) only in TaTME. There was 1 case of T4 with incomplete purse-string suture and 1 case of positive MRF with dissection failure. All patients were followed up for an average of 32.5 months without local recurrence. Conclusion CEA and CK20 levels were high only in TaTME and were related to tumor factors or intraoperative events. However, whether the detection amount is clinically related to local recurrence remains unclear.

Abamectin offers great protection against Bursaphelenchus xylophilus, a well-known devastating pathogen of pine tree stands. Trunk injection of nematicides is currently the most preferred method of control. This study aimed to evaluate the potency of the commonly used formulations of abamectin against B. xylophilus. Twenty-one formulations of abamectin were evaluated by comparing their sublethal toxicities and reproduction inhibition potentials against B. xylophilus. Nematodes were treated with diluted formulation concentrations in multi-well culture plates. And, populations pre-exposed to pre-determined concentrations of the formulations were inoculated onto Botrytis cinerea culture, and in pine twig cuttings. Potency was contrastingly different among formulations, with LC95 of 0.00285 and 0.39462 mg/ml for the most, and the least potent formulation, respectively. Paralysis generally occurred at an application dose of 0.06 μg/ml or higher, and formulations with high sublethal toxicities caused significant paralysis levels at the tested doses, albeit the variations. Nematode reproduction was evident at lower doses of 0.00053–0.0006 μg/ml both on Botrytis cinerea and pine twigs, with significant variations among formulations. Thus, the study highlighted the inconsistencies in the potency of similar product formulations with the same active ingredient concentration against the target organism, and the need to analyze the potential antagonistic effects of the additives used in formulations.

Abstract Background The aim of the study is to evaluate the risk factors of anastomotic leakage (AL) and develop a nomogram to predict the risk of AL in surgical management of primary ovarian cancer. Methods We retrospectively reviewed 770 patients with primary ovarian cancer who underwent surgical resection of the rectosigmoid colon as part of cytoreductive surgery between January 2000 to December 2020. AL was defined based on radiologic studies or sigmoidoscopy with relevant clinical findings. Logistic regression analyses were performed to identify the risk factor of AL, and a nomogram was developed based on the multivariable analysis. The bootstrapped-concordance index was used for internal validation of the nomogram, and calibration plots were constructed. Results The incidence of AL after resection of the rectosigmoid colon was 4.2% (32/770). Diabetes (OR 3.79; 95% CI, 1.31–12.69; p = 0.031), co-operation with distal pancreatectomy (OR, 4.8150; 95% CI, 1.35–17.10; p = 0.015), macroscopic residual tumor (OR, 7.43; 95% CI, 3.24–17.07; p = 0

The pine wood nematode (PWN), Bursaphelenchus xylophilus is a well-known devastating pathogen of economic importance in the Republic of Korea and other countries. In the Republic of Korea, trunk injection of nematicides is the preferred method of control. In this study, the efficacy of 16 locally produced formulations of emamectin benzoate against the PWN are compared through determining their sublethal toxicities and reproduction inhibition potentials. Nematodes were treated with varying concentrations of the tested chemicals in multi-well culture plates, and rates of paralysis and mortality were determined after 24 h. Reproduction inhibition potential was tested by inoculating pre-treated nematodes onto Botrytis cinerea, and in pine twig cuttings. Despite the uniformity in the concentration of the active ingredient, efficacy was contrastingly different among formulations. The formulations evidently conformed to three distinct groups based on similarities in sublethal activity (group 1: LC95 of 0.00768–0.01443 mg/ml; group 2: LC95 of 0.03202–0.07236 mg/ml, and group 3: LC95 of as high as 0.30643–0.40811 mg/ml). Nematode paralysis generally occurred at the application dose of 0.0134–0.1075 μg/ml, and there were significant differences in nematode paralysis rates among the products. Nematode reproduction was only evident at lower doses both on B. cinerea and pine twigs, albeit the variations among formulations. Group 1 formulations significantly reduced nematode reproduction even at a lower dose of 0.001075 μg/ml. The variations in efficacy might be attributed to differences in inert ingredients. Therefore, there is need to analyze the potential antagonistic effects of the large number of additives used in formulations.

Filenchus cylindricus (Thorne & Malek, 1968) Niblack & Bernard, 1985 was reported from the sandy rhizospheric soils of Poa pratensis and for the first time in Korea. Females and males are molecularly characterized and morphological and morphometric data supplied. Identification was made using an integrative approach considering morphological characteristics and inferences drawn from the analyses of the D2-D3 expansion segment of 28S rRNA and ITS1-5.8S-ITS2 of rRNA partial sequences. Females and males from Korea conform to the type descriptions and also to subsequent species descriptions from Iowa and Colorado USA, Sudan and Pakistan. Despite the close morphological and morphometric similarities with F. thornei (Andrássy, 1954) Andrássy, 1963, the two species can be adequately differentiated based on molecular data inference.

Plant-parasitic nematodes are not only an important constraint on agricultural crop production, but also cause both direct and indirect damage to turfgrass, which is a ground cover plant. However, studies on plant-parasitic nematodes of turfgrass in Korea are scarce. A survey for plant-parasitic nematodes was carried out on 13 golf courses in Korea. The results yielded 28 species/taxa belonging to 16 genera and 12 families of plant-parasitic nematodes. Among the isolated species, Helicotylenchus microlobus, Mesocriconema nebraskense, Tylenchorhynchus claytoni, Mesocriconema sp., and Meloidogyne graminicola were the most prevalent species in all management zones. Twelve species were new records of plant-parasitic nematodes in Korea. Highest maximum densities were showed by T. claytoni, Paratylenchus nanus, M. nebraskense, M. graminicola, and H. microlobus. Diversity (H′), was significantly higher in fairways compared to tees and greens, though species evenness (J′) and dominance (D) showed no statistically significant differences. This information is crucial in nematode problem diagnosis, and the subsequent formulation of management strategies.

Purpose This study aimed to assess the evaluation of clinical outcomes and consequences of complications after cytoreductive surgery (CRS) and hyperthermic intraperitoneal chemotherapy (HIPEC) for the peritoneal carcinomatosis (PC) from colorectal cancer. Methods A total 26 patients underwent CRS and HIPEC for PC from colorectal cancer between March 2009 and April 2018. All the patients underwent CRS with the purpose of complete or near-complete cytoreduction. Intraoperative HIPEC was performed simultaneously after the CRS. Mitomycin C was used as chemotherapeutic agent for HIPEC. Results Median disease-free survival was 27.8 months (range, 13.4–42.2 months). Median overall survival was 56.0 months (range, 28.6–83.5 months). The mean peritoneal cancer index (PCI) was 8.73 ± 5.54. The distributions thereof were as follows: PCI

The sugar beet cyst nematode, Heterodera schachtii is a well known pathogen on Chinese cabbage in the highland fields of Korea. However, a race of cyst forming nematode with close morphological resemblance to H. trifolii was recently isolated from the same Chinese cabbage fields. Morphological species differentiation between the two cyst nematodes is challenging, with only minor differences between them. Thus, this study described the newly intercepted H. trifolii population, and reviewed morphological and molecular characteristics conceivably essential in differentiating the two nematode species. A comparison of morphometric measurements of both infective juveniles and vulval cones of cysts showed significant differences between the two cyst nematodes. When total RNA and genomic DNA were extracted from a mixed field population, COI genes and ITS regions were clearly amplified with primers of the two Heterodera species, suggesting that Heterodera population collected from the Chinese cabbage field consisted of a mixture of two species. COI and ITS of H. trifolii were predominantly amplified from nucleotides prepared from H. trifolii monoxenic population whereas those of H. schachtii were strongly detected in H. schachtii monoxenic cultures. Thus, this study confirms the coexistence of the two species in some Chinese cabbage fields; and the presence of H. trifolii in Korea is reported here for the first time.

Purpose Studies investigating the appropriate post-surgery follow-up method for elderly patients with colorectal cancer are limited. Thus, the purpose of this study was to compare survival rates between two follow-up methods in patients aged 80 years or older who underwent surgery for colorectal cancer. Methods Between January 1, 2002 and December 31, 2010, 165 patients aged 80 years or older underwent curative resection for non-metastatic colorectal cancer at the Department of Surgery, Seoul National University Hospital. Sixty-six of these patients were excluded due to the lack of follow-up, while the remaining 99 were included in our study. These 99 patients were divided into the following two groups depending on their post-surgery follow-up method. Patients who underwent follow-up on a regular basis, which was defined as once every six months to one year, with carcinoembryonic antigen (CEA) and computed tomography (CT) comprised the Regular group, and those who received follow-up with CEA alone or underwent CT procedures once every two years or more comprised the Minimal group. Overall survival was analyzed with the log-rank test and Cox regression analysis. Results Of the 99 patients, 62 were in Regular group and 37 were in Minimal group. There was no difference in overall survival rate between the two post-surgery follow-up methods (regular group vs. minimal group: 51.6% vs. 50.9% [5-year overall survival rate], P=0.819). Additionally, no significant differences was detected between the groups following multivariate analysis (harzard ratio=0.907; 95% confidence interval=0.460–1.788, P=0.777). Conclusion A significant survival gain was not observed between Regular and Minimal group. To draw a more definite conclusion, a multi-center randomized research study should be conducted.

Purpose To evaluate the effect of repeated debulking surgery for high-grade pseudomyxoma peritonei (PMP) originating from the appendix. Methods Between January 1998 and December 2014, fifty patients, who underwent debulking surgery for high-grade PMP originating from the appendix, were obtained from a prospectively collected database and retrospectively analyzed. Two groups according to the number of operations were divided and analyzed. Results A total of 118 operations were performed. Thirty-one patients received more than two operations. The median interval between operations was 18.2 months (range, 2–170 months). Complications developed after 26 operations (22.0%), including ileus (n=10), intra-ab-dominal fluid collection (n=7), surgical site infection (n=5), and others. There were two mortalities within 30 days after operation. Between two groups of patients who received one operation only and patients who received more than two operations, transfusion, diversion operation, and postoperative complication rate showed statistically significant differences. Two groups of patients had no differences in overall survival rates. Conclusion Our results indicate that the number of operations does not affect the survival rate of high-grade appendiceal PMP, in which repeated debulking surgery is vital to relieve symptoms of the tumor burden.

Purpose Neuroendocrine tumor is a rare tumor in the rectum, but incidence has been increasing. Local excision is an option for treatment of small tumors, and transanal excision or endoscopic resection can be undergone. But indications for local excision have not been established yet. This study was to compare the long-term oncologic outcomes between transanal excision and endoscopic resection for rectal neuroendocrine tumor. Methods Patients diagnosed and treated with rectal neuroendocrine tumor from 2000 to 2015 were collected prospectively, and medical records were analyzed retrospectively. Results Forty patients were included, mean age was 50.20±13.35 years (male:female=23:17). Transanal excision and endoscopic resection were performed in 28 (70%) and 12 (30%) patients, respectively. Mean tumor size was 0.63±0.37 cm, and tumor location was 5.45±1.89 cm from anal verge. Tumor location was more distal rectum in transanal excision (5.04±1.73 cm vs. 6.42±1.98 cm, P=0.049). Pathologic T stage was T1 in all patients. Most of the patients (90%) showed tumor grade 1. After median 24 months (range, 0–86 months) follow-up, one patient (2.5%) experienced local recurrence. The patient underwent further transanal excision. There was no mortality after local excision. Conclusion Local excision is a safe and effective treatment for small-sized neuroendocrine tumors in rectum.

Two buprestid species, Paracylindromorphus japanensis (Saunders 1873) and Paracylindromorphus richteri Théry, 1937, of the tribe Aphanisticini Jacquelin du Val, 1863 are known from Korea to date. As the first species of the genus Aphanisticus of this tribe, Aphanisticus congener Saunders, 1873 is recorded from Korea herein. A key of the Korean Aphanisticini species, and a redescription and photographs of the first Korean recorded species are provided.

Two-component systems (TCSs) are critical to the pathogenesis of Xanthomonas oryzae pv. oryzae (Xoo). We mutated 55 of 62 genes annotated as responsive regulators (RRs) of TCSs in the genome of Xoo strain PXO99A and identified 9 genes involved in Xoo virulence. Four (rpfG, hrpG, stoS, and detR) of the 9 genes were previously reported as key regulators of Xoo virulence and the other 5 have not been characterized. Lesion lengths on rice leaves inoculated with the mutants were shorter than those of the wild type and were significantly restored with gene complementation. The population density of the 5 mutants in planta was smaller than that of PXO99A at 14 days after inoculation, but the growth curves of the mutants in rich medium were similar to those of the wild type. These newly reported RR genes will facilitate studies on the function of TCSs and of the integrated regulation of TCSs for Xoo pathogenesis.

Purpose: To evaluate the usefulness of ridge augmentation using a customized titanium mesh (CTM) that was preformed by trimming and bending the commercial titanium mesh on a virtually reconstructed 3D acrylic resin model using clinical, radiologic, histologic, and histomorphometric analyses. Materials and Methods: This study was designed prospectively for patients who required vertical ridge augmentation using a staged approach before implant surgery. After installation of the CTM, grafting was performed using deproteinized porcine bone mineral covered with an absorbable membrane. Computed tomography was performed preoperatively and 6 months after simultaneous/staged guided bone regeneration to measure planned, reconstructed, and lacking bone volume, and the reconstruction rate was calculated based on these values. Clinical complications were also recorded, particularly the mesh exposure rate. At re-entry, the bone core was obtained using a trephine bur, and histologic and histomorphometric analyses were performed. Results: A total of 10 sites in eight patients were used for the study analysis. The mean planned bone volume was 1.15 cm3 (range: 0.78 to 1.56 cm3), mean lacking bone volume was 0.13 cm3 (range: 0 to 0.59 cm3), and mean reconstructed bone volume was 1.02 cm3 (range: 0.56 to 1.43 cm3). The exposure rate was 30% (3 out of 10 sites). The reconstruction rate was over 80%, except for one case that showed suppuration. From histomorphometric analysis, 27.52% ± 16.87% of new bone, 7.62% ± 5.19% of residual graft, and 64.86% ± 23.76% of connective tissue were observed. The core biopsy samples demonstrated different pseudoperiosteum layer appearances based on the healing stage of the augmented sites. In the premature bone, the inner osteogenic layer consisted of multiple layers of osteoblast cells with adjacent large blood vessels. However, in the mature augmented site, there was no specific inner osteogenic layer, and the outer fibrous layer was dominant. Conclusions: The fabrication of CTM based on the application of the 3D-printing technique makes vertical ridge augmentation easier and can reduce complications and achieve target bone acquisition. In addition, it is expected that quantitative analysis of the pseudoperiosteum layer will be facilitated using the CTM. [ABSTRACT FROM AUTHOR]

The aim of this case report was to present clinical, radiologic, and histologic healing outcomes following functional endoscopic sinus surgery (FESS) to manage maxillary sinusitis after lateral sinus augmentation. Three patients who underwent lateral sinus augmentation developed maxillary sinusitis after 3 to 4 weeks. Pharmacologic interventions were performed, but the patients' symptoms did not resolve. The patients were referred to an otorhinolaryngologist and underwent FESS without the removal of bone substitute material or implants. The patients' symptoms disappeared completely after FESS. The implants were osseointegrated successfully and have functioned well to date (between 4 months and 7 years after definitive prosthesis delivery). No pathologic change was noted clinically or radiologically after FESS. However, biopsy specimens demonstrated some new bone formation with varying degrees of fibrotic change and tissue density, which is not compatible with the clinical and radiologic observations. FESS without intraoral debridement may be sufficient to resolve maxillary sinusitis after lateral sinus augmentation; this may not lead to favorable histologic healing in the augmented sinus. [ABSTRACT FROM AUTHOR]