Role of subcutaneous closed suction drain in the prevention of incisional surgical site infection after loop ileostomy reversal with purse-string skin closure: a retrospective observational study.

BACKGROUND: Surgical site infection (SSI) is not rare after loop ileostomy reversal. This study assessed the effects of a subcutaneous closed suction drain on reducing SSIs after loop ileostomy reversal with purse-string skin closure. METHODS: This retrospective study included 229 patients who underwent loop ileostomy reversal with purse-string closure at the Pusan National University Yangsan Hospital between January 2017 and December 2021. We divided the patients into those with a subcutaneous drain (SD group) and those without it (ND group). We analyzed variables that affected SSI occurrence in both groups. RESULTS: The SD and ND groups included 109 and 120 patients, respectively. The number of incisional SSIs was significantly lower in the SD than in the ND group (0 vs. 7 events). An average of 35.7 mL of fluid was collected in the drainage bulb during hospitalization. The C-reactive protein level on postoperative day 4 was significantly lower in the SD group than in the ND group. The insertion of a subcutaneous drain was the only factor associated with a reduced incidence of SSIs (p = 0.015). CONCLUSIONS: Subcutaneous closed suction drain with purse-string skin closure in loop ileostomy reversal can reduce incisional SSI occurrence.

Laparoscopic versus open surgery for left flexure colon cancer: A propensity score matched analysis from an international cohort.

AIM: Surgical treatment of splenic flexure cancer (SFC) still presents some debated issues, including the role of laparoscopic surgery. The literature is based on small single-centre series, while randomized controlled studies comparing open and laparoscopic treatment for colon cancer exclude SFC. This study aimed to determine the role of laparoscopic surgery in the treatment of SFC, comparing short- and long-term outcomes with open surgery. METHOD: This was an international multicentre retrospective cohort study that analysed patients from 10 tertiary referral centres. From a cohort of 641 cases, 484 patients with Stage I-III SFC submitted to elective surgery with curative intent were selected. After 1:1 propensity score matching, 130 patients in the laparoscopic group (LapGroup) were compared with 130 patients in the open surgery group (OpenGroup). RESULTS: After propensity score matching, the two groups were comparable for demographic and clinical parameters. OpenGroup presented a higher incidence of overall (P = 0.02) and surgery-related complications (P = 0.05) but a similar rate of severe complications (P = 0.75). Length of stay was notably shorter in the LapGroup (P = 0.001). Overall (P = 0.793) as well as cancer-specific survival (P = 0.63) did not differ between the two groups. CONCLUSIONS: Elective laparoscopic surgery for Stage I-III SFC is feasible and associated with improved short-term postoperative outcomes compared to open surgery. Moreover, laparoscopic surgery appears to provide excellent long-term cancer outcomes.

Optimal ICG dosage of preoperative colonoscopic tattooing for fluorescence-guided laparoscopic colorectal surgery.

BACKGROUND: Indocyanine green (ICG) is a multifunctional dye used in tumor localization, tissue perfusion, and lymph node (LN) mapping during fluorescence-guided laparoscopic colorectal surgery. PURPOSE: This study aimed to establish the optimal protocol for preoperative endoscopic submucosal ICG injection to perform fluorescence lymph node mapping (FLNM), along with undisturbed fluorescent tumor localization and ICG angiography during a single surgery. METHODS: Colorectal cancer patients (n = 192) were enrolled from May 2017 to December 2019. Colonoscopic submucosal ICG injection was performed 12 to 18 h before surgery. ICG injection protocols were modified based on the total injected ICG (mg) and tattooing site number. The concentrations of ICG were gradually decreased from the standard dose (2.5 mg/ml) to the minimum dose (0.2 mg/ml). Successful FLNM (FLNM-s) was defined as distinct fluorescent LNs observed under NIR camera. The patient's age, sex, body mass index (BMI), stage, cancer location, obstruction, and laboratory findings were compared between the FLNM-s and failed FLNM (FLNM-f) groups to identify clinical and pathological factors that affect FLNM. RESULTS: In the ICG dose section of 0.5 to 1 mg, the success rate was highest within all functions including FLNM, fluorescent tumor localization, and ICG angiography. FLNM-s was related to ICG dose (0.5-1 mg), multiple submucosal injections, location of cancer, camera light source, and lower BMI. In the multivariate analysis, camera light source, non-obesity, and multiple injections were independent factors for FLNM-s). The mean total number of harvested LNs was significantly higher in the FLNM-s group than that in the FLNM-f group (p < 0.001). The number of metastatic lymph nodes was comparable between the two groups (p = 0.859). CONCLUSIONS: Preoperative, endoscopic submucosal ICG injection with dose range 0.5 to 1 mg would be optimal protocol for multifunctional ICG applications during fluorescence-guided laparoscopic colorectal surgery.

Absent or impaired rectoanal inhibitory reflex as a diagnostic factor for high-grade (grade III-V) rectal prolapse: a retrospective study.

BACKGROUND: Clinically diagnosing high-grade (III-V) rectal prolapse might be difficult, and the prolapse can often be overlooked. Even though defecography is the significant diagnostic tool for rectal prolapse, it is noticed that rectoanal inhibitory reflex (RAIR) can be associated with rectal prolapse. This study investigated whether RAIR can be used as a diagnostic factor for rectal prolapse. METHODS: In this retrospective study, we evaluated 107 patients who underwent both anorectal manometry and defecography between July 2012 and December 2019. Rectal prolapse was classified in accordance with the Oxford Rectal Prolapse Grading System. Patients in the high-grade (III-V) rectal prolapse (high-grade group, n = 30), and patients with no rectal prolapse or low-grade (I, II) rectal prolapse (low-grade group, n = 77) were analyzed. Clinical variables, including symptoms such as fecal incontinence, feeling of prolapse, and history were collected. Symptoms were assessed using yes/no surveys answered by the patients. The manometric results were also evaluated. RESULTS: Frequencies of fecal incontinence (p = 0.002) and feeling of prolapse (p < 0.001) were significantly higher in the high-grade group. The maximum resting (77.5 vs. 96 mmHg, p = 0.011) and squeezing (128.7 vs. 165 mmHg, p = 0.010) anal pressures were significantly lower in the high-grade group. The frequency of absent or impaired RAIR was significantly higher in the high-grade group (19 cases, 63% vs. 20 cases, 26%, p < 0.001). In a multivariate analysis, the feeling of prolapse (odds ratio [OR], 23.88; 95% confidence interval [CI], 4.43-128.78; p < 0.001) and absent or impaired RAIR (OR, 5.36; 95% CI, 1.91-15.04, p = 0.001) were independent factors of high-grade (III-V) rectal prolapse. In addition, the percentage of the absent or impaired RAIR significantly increased with grading increase of rectal prolapse (p < 0.001). The sensitivity of absent or impaired RAIR as a predictor of high-grade prolapse was 63.3% and specificity 74.0%. CONCLUSIONS: Absent or impaired RAIR was a meaningful diagnostic factor of high-grade (III-V) rectal prolapse. Furthermore, the absent or impaired reflex had a positive linear trend according to the increase of rectal prolapse grading.

Optimization of indocyanine green angiography for colon perfusion during laparoscopic colorectal surgery.

AIM: This study aims to evaluate the extrinsic effects of conditional factors affecting quantitative parameters and to establish the optimization of indocyanine green (ICG) angiography using in vitro experiments and a prospective observational study. METHOD: In vitro experiments were performed to evaluate the correlation between conditional factors such as camera distance, surrounding lighting, fluorescence emission sources and ICG doses. The fluorescence intensity was measured from the ICG-containing test tube in each condition. In the clinical study, ICG angiography was applied to patients with colorectal cancer (n = 164). The quantitative perfusion parameters were the maximal fluorescence intensity (FMAX ), slope, T1/2MAX and perfusion time ratio (TR). Camera position, distance to colon, fluorescence emission source, surrounding lighting, site of angiography and ICG specific mode were considered as conditional factors and compared with the quantitative parameters to identify the optimal condition of ICG angiography. RESULTS: The fluorescence intensity had an inverse correlation with distance, and the transitional zone was shown at a distance of 4-5 cm by slope differential. FMAX , T1/2MAX and slope were affected significantly by camera distance, site of angiography, fluorescence emission source and ICG mode as conditional factors. On multivariate analysis, FMAX was independently associated with spectral ICG mode with red inversion, laser mode and camera distance. Conversely, TR was not related to any conditional factors. CONCLUSION: Since quantitative parameters of ICG angiography are influenced by various conditions, a standardized protocol is required. The application of ICG specific modes with a constant distance of 4-5 cm can provide optimized fluorescence images.

Clinical-Pathologic Characteristics and Long-term Outcomes of Left Flexure Colonic Cancer: A Retrospective Analysis of an International Multicenter Cohort.

BACKGROUND: Colorectal cancer seldom presents at the splenic flexure. Small series on left flexure tumors reported a high occurrence of negative prognostic factors called into question as causes of poor prognosis. However, because of the small number of cases, no definite conclusions can be drawn. OBJECTIVE: The aim of this study was to compare clinical-pathologic characteristics and short- and long-term outcomes of left flexure tumors with other colonic locations. DESIGN: This was a retrospective analysis of consecutive patients who underwent surgery for tumors at the splenic flexure. Each tumor was paired in a 1 to 1 fashion with a right-sided and sigmoid tumor. SETTINGS: The study was conducted in 10 international centers. PATIENTS: A total of 641 patients with left flexure tumors were included in the study. MAIN OUTCOME MEASURES: Overall survival and cancer-specific survival were measured. RESULTS: Left flexure tumors presented more frequently with stenosis (30.5%; p < 0.001), with lesions infiltrating beyond the serosa (21.9%; p = 0.001) and with a high rate of mucinous histology (8.8%; p = 0.001). Looking at long-term prognosis, no differences were observed among the 3 groups, both considering overall and cancer-specific survival. However, left flexure tumors recurred more frequently as peritoneal carcinomatosis (20.6%; p < 0.001). LIMITATIONS: This study was limited because of its retrospective nature. CONCLUSIONS: Although left flexure tumors display several negative prognostic factors, they are not characterized by a worse prognosis compared with other colon cancer locations. See Video Abstract at http://links.lww.com/DCR/B395. CARACTERÍSTICAS CLÍNICO-PATOLÓGICAS Y RESULTADOS A LARGO PLAZO DEL CÁNCER DE COLON DE ÁNGULO IZQUIERDO: UN ANÁLISIS RETROSPECTIVO DE UNA COHORTE MULTICÉNTRICA INTERNACIONAL: El cáncer colorrectal rara vez se presenta en el ángulo esplénico. Pequeñas series sobre tumores de ángulo izquierdo informaron una alta incidencia de factores pronósticos negativos cuestionados como causas de mal pronóstico. Sin embargo, debido al pequeño número de casos, no se pueden sacar conclusiones definitivas.El objetivo de este estudio fue comparar las características clínico-patológicas, los resultados a corto y largo plazo de los tumores de ángulo izquierdo con otras ubicaciones de colon.Análisis retrospectivo de pacientes consecutivos que se sometieron a cirugía por tumores en el ángulo esplénico. Cada tumor se emparejó de forma individual con un tumor del lado derecho y sigmoide.El estudio se realizó en 10 centros internacionales.Se incluyeron en el estudio un total de 641 pacientes con tumores del ángulo izquierdo.Supervivencia general y específica del cáncerLos tumores de ángulo izquierda se presentaron con mayor frecuencia con estenosis (30.5%, p <0.001), con lesiones infiltradas más allá de la serosa (21.9%, p = 0.001), y con una alta tasa de histología mucinosa (8.8%, p = 0.001). En cuanto al pronóstico a largo plazo, no se observaron diferencias entre los tres grupos, considerando la supervivencia general y específica del cáncer. Sin embargo, los tumores de ángulo izquierdo recurrieron con mayor frecuencia como carcinomatosis peritoneal (20,6%; p <0,001).Este estudio fue limitado debido a su naturaleza retrospectiva.Aunque los tumores de ángulo izquierdo muestran varios factores pronósticos negativos, no se caracterizan por un peor pronóstico en comparación con otras ubicaciones de cáncer de colon. Consulte Video Resumen en http://links.lww.com/DCR/B395.

Efficacy of preoperative colonoscopic tattooing with indocyanine green on lymph node harvest and factors associated with inadequate lymph node harvest in colorectal cancer.

Objective: Adequate lymph node harvest (LNH) in colorectal cancer is closely related to survival. This study aimed to evaluate the effect of preoperative colonoscopic tattooing (PCT) with indocyanine green (ICG) on adequate LNH in colorectal cancer. Materials and methods: A total of 1079 patients who underwent surgical resection for colorectal cancer were divided into two groups: a tattooing group and a non-tattooing group. The patients were retrospectively analyzed for the number and adequacy of LNH according to tumor locations and stages. Univariate and multivariate analysis for factors associated with adequate LNH were done. Results: There was no significant difference between the two groups in the number and adequacy of LNH according to tumor locations. However, T1 colorectal cancer in the tattooing group had significantly higher adequate LNH (91.6% vs 82.1%, OR 2.370, p = .048) and T1 and N0 rectal cancer in the tattooing group also had higher adequate LNH although there was no statistical significance (100% vs 82.4%, OR 12.088, p = .095; 96.9% vs 84.8%, OR 5.570, p = .099) when compared to the non-tattooing group. Male sex and T1 stage were significantly associated with inadequate LNH in multivariate analysis (OR 0.556 (95% CI 0.340-0.909), p = .019; OR 0.555 (95% CI 0.339-0.910), p = .019, respectively). Conclusion: PCT with ICG did not improve adequate LNH in colorectal cancer but effectively improved adequate LNH in early colorectal cancer. Male sex and early cancer were risk factors for inadequate LNH in colorectal cancer, so PCT is needed for adequate LNH in these patients.

Quantitative analysis of colon perfusion pattern using indocyanine green (ICG) angiography in laparoscopic colorectal surgery.

PURPOSE: This study aimed to quantitatively evaluate colon perfusion patterns using indocyanine green (ICG) angiography to find the most reliable predictive factor of anastomotic complications after laparoscopic colorectal surgery. METHODS: Laparoscopic fluorescence imaging was applied to colorectal cancer patients (n = 86) from July 2015 to December 2017. ICG (0.25 mg/kg) was slowly injected into peripheral blood vessels, and the fluorescence intensity of colonic flow was measured sequentially, producing perfusion graphs using a video analysis and modeling tool. Colon perfusion patterns were categorized as either fast, moderate, or slow based on their fluorescence slope, T1/2MAX and time ratio (TR = T1/2MAX/TMAX). Clinical factors and quantitative perfusion factors were analyzed to identify predictors for anastomotic complications. RESULTS: The mean age of patients was 65.4 years, and the male-to-female ratio was 63:23. Their operations were laparoscopic low anterior resection (55 cases) and anterior resection (31 cases). The incidence of anastomotic complication was 7%, including colonic necrosis (n = 1), anastomotic leak (n = 3), delayed pelvic abscess (n = 1), and delayed anastomotic dehiscence (n = 1). Based on quantitative analysis, the fluorescence slope, T1/2MAX, and TR were related with anastomotic complications. The cut-off value of TR to categorize the perfusion pattern was determined to be 0.6, as shown by ROC curve analysis (AUC 0.929, P < 0.001). Slow perfusion (TR > 0.6) was independent factor for anastomotic complications in a logistic regression model (OR 130.84; 95% CI 6.45-2654.75; P = 0.002). Anastomotic complications were significantly correlated with the novel factor TR (> 0.6) as the most reliable predictor of perfusion and anastomotic complications. CONCLUSIONS: Quantitative analysis of ICG perfusion patterns using T1/2MAX and TR can be applied to detect segments with poor perfusion, thereby reducing anastomotic complications during laparoscopic colorectal surgery.

Korean Society of Coloproctology (KSCP) trial of cONsolidation Chemotherapy for Locally advanced mid or low rectal cancer after neoadjUvant concurrent chemoraDiothErapy: a multicenter, randomized controlled trial (KONCLUDE).

BACKGROUND: Neoadjuvant chemoradiotherapy (CRT) followed by total mesorectal excision (TME) has been a standard treatment option for locally advanced rectal cancer with improved local control. However, systemic recurrence despite neoadjuvant CRT remained unchanged. The only significant prognostic factor proven to be important was pathologic complete response (pCR) after neoadjuvant CRT. Several efforts have been tried to improve survival of patients who treated with neoadjuvant CRT and to achieve more pCR including adding cytotoxic chemotherapeutic agents, chronologic modification of chemotherapy schedule or adding chemotherapy during the perioperative period. Consolidation chemotherapy is adding several cycles of chemotherapy between neoadjuvant CRT and TME. It could increase pCR rate, subsequently could show better oncologic outcomes. METHODS: Patients with advanced mid or low rectal cancer who received neoadjuvant CRT will be included after screening. They will be randomized and assigned to undergo TME followed by 8 cycles of adjuvant chemotherapy (control arm) or receive 3 cycles of consolidation chemotherapy before TME, and receive 5 cycles of adjuvant chemotherapy (experimental arm). The primary endpoints are pCR and 3-year disease-free survival (DFS), and the secondary endpoints are radiotherapy-related complications, R0 resection rate, tumor response rate, surgery-related morbidity, and peripheral neuropathy at 3 year after the surgery. The authors hypothesize that the experimental arm would show a 15% improvement in pCR (15 to 30%) and in 3-year DFS (65 to 80%), compared with the control arm. The accrual period is 2 years and the follow-up period is 3 years. Based on the superiority design, one-sided log-rank test with α-error of 0.025 and a power of 80% was conducted. Allowing for a drop-out rate of 10%, 358 patients (179 per arm) will need to be recruited. Patients will be followed up at every 3 months for 2 years and then every 6 months for 3 years after the last patient has been randomized. DISCUSSION: KONCLUDE trial aims to investigate whether consolidation chemotherapy shows better pCR and 3-year DFS than adjuvant chemotherapy alone for the patients who received neoadjuvant CRT for locally advanced rectal cancer. This trial is expected to provide evidence to support clear treatment guidelines for patients with locally advanced rectal cancer. TRIAL REGISTRATION: Clinicaltrials.gov NCT02843191 (First posted on July 25, 2016).

Enhanced Photosensing and Photodynamic Treatment of Colon Cancer Cells Using Methoxy Poly(ethylene glycol)-Conjugated Chlorin e6.

Nanophotosensitizer composed of methoxy poly(ethylene glycol) (MePEG) and chlorin e6 (Ce6) (abbreviated as Pe6) was synthesized for efficient delivery of Ce6 to the colon cancer cells. Pe6 nanophotosensitizer has small diameter less than 100 nm with spherical shape and core-shell structure. They were activated in aqueous solution while Ce6 was quenched due to its poor aqueous solubility. They showed no intrinsic cytotoxicity against normal cells and colon cancer cells. Pe6 nanophotosensitizers showed enhanced cellular uptake, phototoxicity, and reactive oxygen species (ROS) generation at in vitro cell culture experiment. Furthermore, they showed improved tumor tissue penetration and accumulation in vivo animal studies. We suggested Pe6 nanophotosensitizers as an ideal candidate for PDT of colon cancer.

Perineal squamous cell carcinoma arising from an epidermal cyst: a case report.

BACKGROUND: Epidermal cysts and squamous cell carcinomas (SCCs) are common skin lesions. However, a malignant change in an epidermal cyst is very rare. The incidence of a malignant change from an epidermal cyst to cutaneous SCC is 0.011-0.045%. In particular, malignant transformation of an epidermal cyst in the perineum is extremely rare. To date, three cases have been reported in the English literature. CASE PRESENTATION: We report a case of 51-year-old male with an approximately 15-cm perineal mass. This mass started to grow suddenly 4 months previously and caused great discomfort in the perineum due to the large size. The patient underwent excision of the mass with a negative margin. Histopathological analysis confirmed a microinvasive SCC arising from a proliferating epidermoid cyst. CONCLUSIONS: Even if benign tumors are suspected, a change in size, pain, ulceration, or discharge should indicate the need for surgical resection due to the possibility of a malignant change.

Appendiceal intussusception requiring an ileocecectomy: a case report and comment on the optimal surgery.

BACKGROUND: Appendiceal intussusception is very rare condition with an estimated incidence of 0.01%. Therefore, it is likely to be overlooked. In addition, making the diagnosis before or during surgery is very difficult. CASE PRESENTATION: A 60-year-old male who was referred to our gastroenterology center with cecal inflammation found during a colonoscopy. An abdominal computed tomography (CT) following endoscopy revealed a 5 × 2.5 × 4 cm mass-like lesion in the cecum around the ileocolic (IC) valve and appendiceal orifice. The main lesion seemed to be an inflammatory mass rather than a malignancy because it appeared to be an extraluminal or extramucosal lesion. Ultrasonography revealed diffuse wall thickening of the cecum around the appendiceal orifice that was suspicious for an inflammatory mass or a benign mass. A diagnosis was uncertain. The differential diagnosis included chronic appendicitis, appendiceal neoplasm such as appendiceal mucocele, low grade appendiceal mucinous neoplasm. The patient underwent a laparoscopic partial cecectomy. In the surgical field, there was a large mass in the appendiceal orifice. The cecum was partially resected, with care taken to preserve the IC valve. Final histopathological analysis of the surgical specimen revealed an appendiceal intussusception without any mucosal lesion of the appendix. Narrowing of the terminal ileum with a small bowel obstruction and stenosis of the IC valve occurred postoperatively. Therefore, ileocecectomy was performed via a laparoscopic approach. The patient was discharged 11 days after the second surgery without another significant postoperative complication. CONCLUSIONS: We report a rare case of appendiceal intussusception that required reoperation due to ileocolic valve stenosis. If the correct diagnosis of appendiceal intussusception is made, we can select an appropriate surgical treatment based on the classification of appendiceal intussusceptions.

Colonic perforation either during or after stent insertion as a bridge to surgery for malignant colorectal obstruction increases the risk of peritoneal seeding.

BACKGROUND: Endoscopic colorectal stenting may be performed as a bridge to surgery in patients with malignant colorectal obstruction, and has been reported to be associated with a high rate of successful primary anastomosis, low rate of stoma formation, and shorter hospital stay. However, the results of recent studies suggest that colorectal stenting could potentially worsen the prognosis. This study aimed to compare outcomes between patients who underwent colorectal stenting as a bridge to surgery and patients who underwent curative surgery only for malignant colorectal obstruction. METHODS: This study included patients with malignant colorectal obstruction and symptomatic bowel dilatation who were treated by stenting as a bridge to surgery (stent group, n = 27) or surgical resection only (surgery-only group, n = 29) between May 2009 and May 2012. The short-term outcomes evaluated were the primary anastomosis rate, length of hospital stay, and rates of emergency and open surgery. The long-term outcomes evaluated were overall survival (OS) and recurrence-free survival (RFS). RESULTS: The primary outcomes were similar in the two groups. There were no significant differences between the stent and surgery-only groups in 3-year OS (85.2 vs. 82.8%; p = 0.655) or 3-year RFS (80.7 vs. 78.6%; p = 0.916). The odds ratio for seeded metastasis after perforation either during or after stent placement was 46.0 (95% CI, 2.0-1,047.8; p = 0.016). CONCLUSIONS: Colorectal stenting as a bridge to surgery showed no significant short- or long-term benefits compared with surgery only, and was associated with peritoneal seeding after perforation. Stenting before surgery should therefore only be considered in patients with a high risk of complications associated with emergency surgery.

Risk factors for delayed gastric emptying caused by anastomosis edema after subtotal gastrectomy for gastric cancer.

BACKGROUND/AIMS: Delayed gastric emptying (DGE) is one of the most troublesome complications after subtotal gastrectomy for gastric cancer. We evaluated operative and perioperative variables to assess for independent risk factors of DGE caused by anastomosis edema. METHODOLOGY: The study retrospectively reviewed clinical data of 382 consecutive patients who underwent subtotal gastrectomy for gastric cancer between 2009 and 2011 at a single institution. RESULTS: Delayed gastric emptying had occurred in twelve patients (3.1%). Univariate analysis revealed high body mass index (>25kg/m2), open gastrectomy, and Billroth II or Roux-en Y reconstructions to be significant factors for delayed gastric emptying. Multivariate analysis identified high body mass index and open gastrectomy as predictors of delayed gastric emptying. CONCLUSIONS: To avoid delayed gastric emptying, surgeons should take care in creating the gastrointestinal anastomosis, particularly in patients with high BMI or in cases of open gastrectomy.

Self-assembled polymeric micelles based on hyaluronic acid-g-poly(D,L-lactide-co-glycolide) copolymer for tumor targeting.

Graft copolymer composed hyaluronic acid (HA) and poly(D,L-lactide-co-glycolide) (PLGA) (HAgLG) was synthesized for antitumor targeting via CD44 receptor of tumor cells. The carboxylic end of PLGA was conjugated with hexamethylenediamine (HMDA) to have amine end group in the end of chain (PLGA-amine). PLGA-amine was coupled with carboxylic acid of HA. Self-assembled polymeric micelles of HAgLG have spherical morphologies and their sizes were around 50-200 nm. Doxorubicin (DOX)-incorporated polymeric micelles were prepared by dialysis procedure. DOX was released over 4 days and its release rate was accelerated by the tumoric enzyme hyaluronidase. To assess targetability of polymeric micelles, CD44-positive HepG2 cells were employed treated with fluorescein isothiocyanate (FITC)-labeled polymeric micelles. HepG2 cells strongly expressed green fluorescence at the cell membrane and cytosol. However, internalization of polymeric micelles were significantly decreased when free HA was pretreated to block the CD44 receptor. Furthermore, the CD44-specific anticancer activity of HAgLG polymeric micelles was confirmed using CD44-negative CT26 cells and CD44-positive HepG2 cells. These results indicated that polymeric micelles of HaLG polymeric micelles have targetability against CD44 receptor of tumor cells. We suggest HAgLG polymeric micelles as a promising candidate for specific drug targeting.

AI-driven automatic compression system for colorectal anastomosis.

Although circular staplers offer technical advancements over traditional hand-sewn techniques, their use remains challenging for unskilled users, necessitating substantial time and experience for mastery. In particular, it is challenging to apply a consistent pressure of an appropriate magnitude. We developed an automated circular anastomosis device using artificial intelligence (AI) to solve this problem. Automation through AI reduces experiential factors during the anastomosis process. We defined damage occurring during the anastomosis process, noting that a greater depth of damage indicated a more severe injury. For automated anastomosis, data at a tissue strain of 40% were used for the AI model, as this strain level showed optimal performance based on the accuracy and cost matrix. We compared the outcomes of automated anastomosis using a trained AI with those of unskilled users. The results were validated using the Shapiro-Wilk test and t tests. Compression damage was verified on collagen sheets. The AI-driven automatic compression system resulted in less damage compared to unskilled users. In particular, a more significant difference in damage was observed in poor-condition collagen than in good-condition collagen. Damage to the collagen under poor conditions was 54.8% when handled by unskilled users, while the AI-driven automatic compression system resulted in 38.9% damage. This study confirmed that novices' use of AI for automated anastomosis reduces the risk of damage, especially for tissues in poor condition.

Effect of Fluorescence Lymph Node Mapping on Improving Diagnostic Values of CT D3 Lymph Node Staging for Right-Sided Colon Cancer.

BACKGROUND/OBJECTIVES: This study evaluated the impact of fluorescence lymph node mapping (FLNM) using indocyanine green (ICG) on the diagnostic accuracy of preoperative computed tomography (CT) in right-sided colon cancer. METHODS: A total of 218 patients who underwent laparoscopic right hemicolectomy with D3 lymph node dissection (LND) were analyzed: 86 patients in the FLNM group and 132 in the conventional surgery group. The FLNM technique allowed for enhanced intraoperative visualization of lymph node (LN) and more precise dissection, improving the identification of metastatic LNs. The diagnostic value of preoperative CT staging was assessed in both the FLNM and control groups by calculating the apparent prevalence, true prevalence, sensitivity, specificity, positive predictive value (PPV), negative predictive value, positive likelihood ratio (PLR), negative likelihood ratio, false positive and false negative proportions, and accuracy. RESULTS: FLNM increased the accuracy of CT staging for detecting D3 LN metastasis in advanced cancer cases, with a higher PPV, PLR, and accuracy. In the FLNM group, the false-positive rate was significantly reduced, and the specificity was higher compared to the control group. Multivariate analysis identified FLNM as an independent factor associated with improved D3 LN metastasis detection. These findings suggest that incorporating FLNM into surgical procedures enhances the diagnostic value of preoperative CT by improving the precision of LND, particularly in patients with advanced colon cancer. CONCLUSIONS: The use of FLNM for D3 LND enhances the diagnostic accuracy of cN staging in right-sided colon cancer by improving surgical precision.

Multicenter analysis of risk factors for anastomotic leakage after laparoscopic rectal cancer excision: the Korean laparoscopic colorectal surgery study group.

OBJECTIVE: To assess the risk factors for clinical anastomotic leakage (AL) in patients undergoing laparoscopic surgery for rectal cancer. BACKGROUND: Little data are available about risk factors for AL after laparoscopic rectal cancer resection. METHODS: This was a retrospective analysis of 1609 patients with rectal cancer who had undergone laparoscopic surgery for rectal cancer with sphincter preservation. Clinical data related to AL were collected from 11 institutions. Univariate and multivariate analyses were performed to determine the risk factors for AL. RESULTS: AL was noted in 101 (6.3%) of the patients. The leakage rate ranged from 2.0% to 10.3% for each hospital (P = 0.04). In patients without protective stomas (n = 1187), male sex [hazard ratio (HR), 3.468], advanced tumor stage (HR, 2.520), lower tumor level (HR, 2.418), preoperative chemoradiation (HR, 6.284), perioperative transfusion (HR, 10.705), and multiple firings of the linear stapler (HR, 6.181) were significantly associated with AL. Our theoretical model suggested that the HR for patients with 2 risk factors was significantly higher than that the HR for patients with no or only 1 risk factor. CONCLUSIONS: Male sex, low anastomosis, preoperative chemoradiation, advanced tumor stage, perioperative bleeding, and multiple firings of the linear stapler increased the risk of AL after laparoscopic surgery for rectal cancer. A diverting stoma might be mandatory in patients with 2 or more of the risk factors identified in this analysis.

Fluorescence-guided colorectal surgery: applications, clinical results, and protocols.

In recent years, the rise of minimally invasive surgery has driven the development of surgical devices. Indocyanine green (ICG) fluorescence imaging is receiving increased attention in colorectal surgery for improved intraoperative visualization and decision-making. ICG, approved by the U.S. Food and Drug Administration in 1959, rapidly binds to plasma proteins and is primarily intravascular. ICG absorption of near-infrared light (750-800 nm) and emission as fluorescence (830 nm) when bound to tissue proteins enhances deep tissue visualization. Applications include assessing anastomotic perfusion, identifying sentinel lymph nodes, and detecting colorectal cancer metastasis. However, standardized protocols and research on clinical outcomes remain limited. This study explores ICG's role, advantages, disadvantages, and potential clinical impact in colorectal surgery.

Impact of non-muscle cutting periumbilical transverse incision on the risk of incisional hernia as compared to midline incision during laparoscopic colon cancer surgery: a study protocol for a multi-centre randomised controlled trial.

BACKGROUND: Minimally invasive surgery has become popular as a surgical approach for colorectal cancer because it has fewer complications related to the abdominal incision and perioperative complications. However, the incidence of incisional hernias in laparoscopic surgery has been reported to be similar to that in open surgery. We developed a new method, the non-muscle-cutting periumbilical transverse incision, for a small incision in laparoscopic colon cancer surgery. This study aims to evaluate the effectiveness of the non-muscle-cutting periumbilical transverse incision in comparison with the midline incision in reducing the incidence of an incisional hernia in patients undergoing laparoscopic colon cancer surgery. METHODS: This is an open-label, multi-centre, parallel, superiority, and randomised trial. Altogether, 174 patients will be allocated in a 1:1 ratio to either the midline incision or the non-muscle-cutting periumbilical transverse incision group, after stratifying by the location of the tumour (right- or left-sided). The primary outcome of this study is the incidence of incisional hernias (both symptomatic and radiologic hernias) at 12 months after surgery. The secondary outcomes include operative outcomes, 30-day postoperative complications, pathological results, and patient-reported outcomes (short form-12 health survey questionnaire and body image questionnaire). Both primary (intention-to-treat) and secondary (as-treated principles) analyses will be performed for all outcomes. The statistical significance level was set at p < 0.05 (two-sided testing). DISCUSSION: This trial may show that the non-muscle-cutting periumbilical transverse incision will reduce the incidence of incisional hernias compared to the midline incision. TRIAL REGISTRATION: Clinical Research Information Service (CRiS) of Republic of Korea, KCT0006082 . Registered on April 12, 2021.