Surgical quality assessment for the prospective study of oncologic outcomes after laparoscopic modified complete mesocolic excision for nonmetastatic right colon cancer (PIONEER study).

BACKGROUND: The modified complete mesocolic excision (mCME) procedure for right-sided colon cancer is a tailored approach based on the original complete mesocolic excision (CME) methodology. Limited studies evaluated the safety and feasibility of laparoscopic mCME using objective surgical quality assessments in patients with right colon cancer. The objectives of the PIONEER study were to evaluate oncologic outcomes after laparoscopic mCME and to identify optimal clinically relevant endpoints and values for standardizing laparoscopic right colon cancer surgery based on short-term outcomes of procedures performed by expert laparoscopic surgeons. MATERIALS AND METHODS: This is an ongoing prospective, multi-institutional, single-arm study conducted at five tertiary colorectal cancer centers in South Korea. Study registrants included 250 patients scheduled for laparoscopic mCME with right-sided colon adenocarcinoma (from the appendix to the proximal half of the transverse colon). The primary endpoint was 3-year disease-free survival. Secondary outcomes included 3-year overall survival, incidence of morbidity in the first 4 weeks postoperatively, completeness of mCME, central radicality, and distribution of metastatic lymph nodes. Survival data will be available after the final follow-up date (June 2024). RESULTS: The postoperative complication rate was 12.9%, with a major complication rate of 2.7%. In 87% of patients, central radicality was achieved with dissection at or beyond the level of complete exposure of the superior mesenteric vein. Mesocolic plane resection with an intact mesocolon was achieved in 75.9% of patients, as assessed through photographs. Metastatic lymph node distribution varied by tumor location and extent. Seven optimal clinically relevant endpoints and values were identified based on the analysis of complications in low-risk patients. CONCLUSIONS: Laparoscopic mCME for right-sided colon cancer produced favorable short-term postoperative outcomes. The identified optimal clinically relevant endpoints and values can serve as a reference for evaluating surgical performance of this procedure.

Long-term Complications of Laparoscopic or Robotic Lateral Pelvic Node Dissection After Preoperative Chemoradiotherapy for Locally Advanced Rectal Cancer.

BACKGROUND: Patients with rectal cancer who underwent lateral pelvic node dissection might be at a higher risk of postoperative complications derived from technical complexity. However, little is known regarding the long-term complications after lateral pelvic node dissection. OBJECTIVES: The study aimed to investigate the long-term complications of preoperative chemoradiotherapy, followed by total mesorectal excision with lateral pelvic node dissection for locally advanced rectal cancers. DESIGN: A retrospective analysis of a prospectively collected database. SETTINGS: This study was conducted in a tertiary cancer center. PATIENTS: Patients with rectal cancer who underwent total mesorectal excision with lateral pelvic node dissection after preoperative chemoradiotherapy between 2011 and 2019 were analyzed. All operations were performed via a laparoscopic or robotic approach. MAIN OUTCOME MEASURES: Long-term complications were defined as adverse events that persisted or newly appeared ≥90 days after surgery and could be related to the surgery. RESULTS: A total of 164 patients underwent total mesorectal excision with lateral pelvic node dissection after preoperative chemoradiotherapy. Short-term and long-term complication rates were 36.0% and 36.6%, respectively. Lymphocele was the most common long-term complication (17.7% of patients), and 11.6% had anastomotic leakage with chronic sinus. Of the patients with long-term complications, 20.7% of patients needed readmission for treatment. Of the 29 patients with lymphocele, 13 (41.0%) experienced spontaneous absorption and 11 (37.9%) required surgical or percutaneous catheter drainage or antibiotics use. Multivariate analysis showed pathologic pelvic node metastases ( p = 0.008), and a higher number of unilateral harvested pelvic nodes ( p = 0.001) were significantly associated with long-term complications. At the last follow-up (median duration of 43 months), 15.9% of patients had unresolved complications. LIMITATIONS: The retrospective design. CONCLUSIONS: Patients undergoing lateral pelvic node dissection experienced a higher frequency of long-term complications, but half of them had asymptomatic lymphoceles, most of which resolved spontaneously. However, further efforts should be paid to reduce anticipated complications related to lateral pelvic node dissection. See Video Abstract . COMPLICACIONES A LARGO PLAZO DE LA DISECCIN DE LOS GANGLIOS LIFTICOS PLVICOS LATERALES LAPAROSCPICA O ROBTICA DESPUS DE LA QUIMIORRADIOTERAPIA PREOPERATORIA CONTRA EL CNCER DEL RECTO LOCALMENTE AVANZADO: ANTECEDENTES:Los pacientes con cáncer del recto sometidos a disección ganglionar linfática pélvica lateral podrían tener mayor riesgo de complicaciones postoperatorias derivadas de la complejidad técnica. Sin embargo, se sabe poco sobre las complicaciones a largo plazo después de la disección de los ganglios linfáticos pélvicos laterales.OBJETIVOS:Investigar las complicaciones a largo plazo de la quimiorradioterapia preoperatoria, seguida de escisión mesorrectal total con disección de los ganglios linfáticos pélvicos laterales contra el cáncer de recto localmente avanzado.DISEÑO:Un análisis retrospectivo de una base de datos recopilada prospectivamente.AJUSTES:Este estudio se llevó a cabo en un centro oncológico terciario.PACIENTES:Se analizaron pacientes con cáncer de recto que se sometieron a escisión mesorrectal total con disección de ganglios linfáticos pélvicos laterales después de quimiorradioterapia preoperatoria entre 2011 y 2019. Todas las operaciones se realizaron mediante abordaje laparoscópico o robótico.PRINCIPALES MEDIDAS DE RESULTADO:Las complicaciones a largo plazo se definieron como eventos adversos que persistieron o aparecieron recientemente ≥ 90 días después de la cirugía y podrían estar relacionados con la cirugía.RESULTADOS:Un total de 164 pacientes se sometieron a escisión mesorrectal total con disección de los ganglios linfáticos pélvicos laterales después de quimiorradioterapia preoperatoria. Las tasas de complicaciones a corto y largo plazo fueron del 36,0% y 36,6%, respectivamente. El linfocele fue la complicación a largo plazo más común (17,7% de los pacientes) y el 11,6% tuvo fuga anastomótica con seno crónico. De los pacientes con complicaciones a largo plazo, el 20,7% de los pacientes necesitaron reingreso para recibir tratamiento. De 29 pacientes con linfocele, 13 (41,0%) experimentaron absorción espontánea y 11 (37,9%) requirieron drenaje quirúrgico o percutáneo con catéter o uso de antibióticos. El análisis multivariado mostró metástasis patológicas en los ganglios linfáticos pélvicos ( p = 0,008) y un mayor número de ganglios pélvicos extraídos unilateralmente ( p = 0,001) se asociaron significativamente con complicaciones a largo plazo. En el último seguimiento (mediana de 43 meses), el 15,9% de los pacientes tuvieron complicaciones no resueltas.LIMITACIÓN:El diseño retrospectivo.CONCLUSIONES:Los pacientes sometidos a disección de ganglios pélvicos linfáticos laterales experimentaron una mayor frecuencia de complicaciones a largo plazo, pero la mitad de ellos tuvieron linfoceles asintomáticos, la mayoría de los cuales se resolvieron espontáneamente. Sin embargo, se deben realizar mayores esfuerzos para reducir las complicaciones previstas relacionadas con la disección de los ganglios linfáticos pélvicos laterales. (Traducción-Dr. Aurian Garcia Gonzalez ).

Sequential Lateral Lymphatic Metastasis Shows Similar Oncologic Outcomes to Upward Spread in Advanced Rectal Cancer After Preoperative Chemoradiotherapy.

BACKGROUND: Whether lateral pelvic node metastasis should be considered as a regional or systemic disease is a long-standing debate. Although previous Japanese studies have considered it to be locoregional disease, Western countries consider it a systemic disease and do not perform lateral pelvic node dissection after preoperative chemoradiotherapy. OBJECTIVE: To evaluate whether lateral pelvic node metastasis is a systemic or regional disease that is amenable to curative resection. DESIGN: Retrospective analysis of a prospectively collected database. SETTING: This study was conducted at a tertiary cancer center. PATIENTS: There were 616 consecutive patients who underwent curative total mesorectal excision alone or with lateral pelvic node dissection after preoperative chemoradiotherapy for locally advanced rectal cancer between 2011 and 2019. MAIN OUTCOME MEASURES: Three-year disease-free and overall survival. RESULTS: A total of 360 patients underwent total mesorectal excision, and 160 patients underwent total mesorectal excision with lateral pelvic node dissection. There was no difference in the 3-year disease-free survival (DFS; p = 0.844) or overall survival rates ( p = 0.921) between the groups. Patients with lateral pelvic node metastasis showed DFS similar to those with perirectal lymph node metastasis in the total mesorectal excision group. In a subgroup analysis, patients with internal iliac pelvic node metastasis showed a disease-free survival comparable to those with perirectal node involvement, and patients with other lateral pelvic node metastasis showed a DFS similar to those with intermediate node involvement. In the lateral pelvic node dissection group, the lateral pelvic node metastatic rate was 32.5%. On multivariate analysis, fewer than 8 of the unilateral harvested lateral pelvic nodes and advanced ypT stage were significantly associated with poor disease-free survival. LIMITATION: The retrospective design. CONCLUSIONS: Lateral lymphatic metastasis showed oncologic outcomes similar to those of upward spread, especially perirectal lymph nodes metastasis. Large cohort studies with long-term follow-up are required to confirm these results. See Video Abstract . LAS METSTASIS LINFTICAS SECUENCIALES LATERALES MUESTRAN RESULTADOS ONCOLGICOS SIMILARES EN LA PROPAGACIN ASCENDENTE DEL CNCER RECTAL AVANZADO DESPUS DE LA RADIOQUIMIOTERAPIA PREOPERATORIA: ANTECEDENTES:Es un debate muy antiguo si las metástasis en los ganglios pélvicos laterales deben considerarse una enfermedad regional o sistémica. Si bien estudios japoneses anteriores las consideran como una enfermedad locorregional, en los países de occidente se las considera como una enfermedad sistémica por la cual no se realiza disección de ganglios pélvicos laterales después de una radioquimioterapia preoperatoria.OBJETIVOS:Evaluar si la metástasis en los ganglios pélvicos laterales se consideran como enfermedad sistémica o enfermedad regional susceptible de resección curativa.DISEÑO:Análisis retrospectivo de una base de datos recopilada prospectivamente.AJUSTE:Este estudio se realizó en un centro oncológico terciario.PACIENTES:616 pacientes consecutivos se sometieron a excisión total del mesorrecto curativa sola o con disección de los ganglios pélvicos laterales después de radioquimioterapia preoperatoria en casos de cáncer de recto localmente avanzado entre 2011 y 2019.PRINCIPALES MEDIDAS DE RESULTADO:Sobrevida global y libre de enfermedad a 3 años.RESULTADOS:Un total de 360 pacientes se sometieron a excisión total del mesorrecto y 160 pacientes se sometieron a excisión total del mesorrecto con disección de ganglios pélvicos laterales.No hubo diferencias en la sobrevida libre de enfermedad a 3 años (p = 0,844) ni en las tasas de sobrevida general (p = 0,921) entre los grupos. Los pacientes con metástasis en los ganglios pélvicos laterales mostraron una sobrevida libre de enfermedad similar a aquellos con metástasis en los ganglios linfáticos perirrectales que se encontraban en el grupo de excisión total del mesorrecto.En el análisis de subgrupos, los pacientes con metástasis en los ganglios pélvicos ilíacos internos mostraron una sobrevida libre de enfermedad comparable a aquellos con afección de los ganglios perirrectales y los pacientes con otras metástasis en los ganglios pélvicos laterales mostraron una sobrevida libre de enfermedad similar a aquellos con afección de los ganglios intermedios.En el grupo de disección de los ganglios pélvicos laterales, la tasa de metástasis en dichos ganglios fué del 32,5%. En el análisis multivariado, < de 8 ganglios pélvicos laterales resecados unilateralmente y el estadio ypT avanzado se asociaron significativamente con una menor sobrevida libre de enfermedad.LIMITACIÓN:El diseño retrospectivo del estudio.CONCLUSIONES:Las metástasis linfáticas laterales mostraron resultados oncológicos similares a la diseminación ascendente, especialmente las metástasis en los ganglios linfáticos perirrectales. Se requieren grandes estudios de cohortes con seguimiento a largo plazo para confirmar estos resultados. (Traducción-Dr. Xavier Delgadillo ).

Comparison of the efficacy and safety of single-port versus multi-port robotic total mesorectal excision for rectal cancer: A propensity score-matched analysis.

BACKGROUND: It is unknown whether the da Vinci single-port system performs similarly to the previous multi-port system during complicated procedures, such as rectal cancer surgery. Therefore, we compared the short-term clinical outcomes of single-port and multi-port robotic total mesorectal excision for the treatment of rectal cancer. METHODS: This retrospective study reviewed 128 patients who underwent robotic total mesorectal excision between July 2020 and June 2022, of whom 84 (42 each: single-port versus multi-port) were included in the propensity score-matched cohort. Perioperative and pathologic outcomes were compared between groups. RESULTS: Median tumor height was similar between groups (single-port versus multi-port, 5.9 ± 2.1 vs 5.6 ± 1.8 cm, P = .719). Preoperative chemoradiotherapy was performed equally. The total operative time was less (160.0 ± 42.2 minutes vs 199.6 ± 78.6 minutes, P = .005), the total length of incision was shorter (4.0 ±0.3 vs 5.4 ± 0.7 cm, P = .003), postoperative hospital stay was shorter (6.2 ±1.7 vs 7.2 ±2.8 days, P = .050), and C-reactive protein levels on postoperative day 3 trended to be lower (7.3 ± 4.7 vs 8.9 ± 5.6 mg/L, P = .096) in the single-port group, compared with the multi-port group. Postoperative complications did not differ between groups (single-port versus multi-port, 11.9% vs 16.6%, P = .864). Anastomotic leakage occurred in 1 and 2 patients in the single-port and multi-port groups, respectively. The circumferential resection margins were positive in 1 patient in the multi-port group. CONCLUSION: The perioperative outcomes of single-port robotic total mesorectal excision were comparable to those of multi-port robotic TME. The single-port robot can be considered a surgical option for treating rectal cancer.

The gender and age differences in the passengers' thermal comfort during cooling and heating conditions in vehicles.

The thermal physiological and psychological responses in vehicles, influenced by gender and age, play a crucial role in ensuring passengers' comfort. However, these differences have often been overlooked. This study aims to comprehensively examine passengers' thermal comfort and investigate gender and age disparities based on their physiological and psychological responses. Experiments were conducted inside a vehicle placed in a climate chamber under cooling and heating conditions, with the collected data subjected to statistical analysis. The findings reveal that males had significantly higher mean skin temperatures in cooling conditions and lower skin temperatures in heating conditions than females. However, overall thermal sensation and comfort did not significantly differ between genders. Interestingly, age-related differences were observed to a limited extent in both conditions. This study provides valuable insights into passengers' thermal responses in vehicles, considering the factors of gender and age, thereby contributing to a comprehensive understanding of thermal comfort in a vehicle environment.

Preoperative sequential short-course radiation therapy and FOLFOX chemotherapy versus long-course chemoradiotherapy for locally advanced rectal cancer: a multicenter, randomized controlled trial (SOLAR trial).

BACKGROUND: Preoperative (chemo)radiotherapy has been widely used as an effective treatment for locally advanced rectal cancer (LARC), leading to a significant reduction in pelvic recurrence rates. Because early administration of intensive chemotherapy for LARC has more advantages than adjuvant chemotherapy, total neoadjuvant therapy (TNT) has been introduced and evaluated to determine whether it can improve tumor response or treatment outcomes. This study aims to investigate whether short-course radiotherapy (SCRT) followed by intensive chemotherapy improves oncologic outcomes compared with traditional preoperative long-course chemoradiotherapy (CRT). METHODS: A multicenter randomized phase II trial involving 364 patients with LARC (cT3-4, cN+, or presence of extramural vascular invasion) will be conducted. Patients will be randomly assigned to the experimental or control arm at a ratio of 1:1. Participants in the experimental arm will receive SCRT (25 Gy in 5 fractions, daily) followed by four cycles of FOLFOX (oxaliplatin, 5-fluorouracil, and folinic acid) as a neoadjuvant treatment, and those in the control arm will receive conventional radiotherapy (45-50.4 Gy in 25-28 fractions, 5 times a week) concurrently with capecitabine or 5-fluorouracil. As a mandatory surgical procedure, total mesorectal excision will be performed 2-5 weeks from the last cycle of chemotherapy in the experimental arm and 6-8 weeks after the last day of radiotherapy in the control arm. The primary endpoint is 3-year disease-free survival, and the secondary endpoints are tumor response, overall survival, toxicities, quality of life, and cost-effectiveness. DISCUSSION: This is the first Korean randomized controlled study comparing SCRT-based TNT with traditional preoperative LC-CRT for LARC. The involvement of experienced colorectal surgeons ensures high-quality surgical resection. SCRT followed by FOLFOX chemotherapy is expected to improve disease-free survival compared with CRT, with potential advantages in tumor response, quality of life, and cost-effectiveness. TRIAL REGISTRATION: This trial is registered at Clinical Research Information under the identifier Service KCT0004874 on April 02, 2020, and at Clinicaltrial.gov under the identifier NCT05673772 on January 06, 2023.

Double-layer adhesives for preventing anastomotic leakage and reducing post-surgical adhesion.

Preventing anastomotic leakage (AL) and postoperative adhesions after gastrointestinal surgery is crucial for ensuring a favorable surgical prognosis. However, AL prevention using tissue adhesives can unintentionally lead to undesirable adhesion formation, while anti-adhesive agents may interfere with wound healing and contribute to AL. In this study, we have developed a double-layer patch, consisting of an adhesive layer on one side, utilizing gallic acid-conjugated chitosan (CHI-G), and an anti-adhesive layer on the opposite side, employing crosslinked hyaluronic acid (cHA). These CHI-G/cHA double-layer adhesives significantly prevented AL by forming physical barriers of CHI-G and reduced post-surgical adhesion at the anastomosis sites by the anti-adhesive layers of cHA. The bursting pressure (161.1 ± 21.6 mmHg) of double-layer adhesives-applied rat intestine at postoperative day 21 was far higher than those of the control (129.4 ± 5.7 mmHg) and the commercial anti-adhesives-applied group (120.8 ± 5.2 mmHg). In addition, adhesion score of double-layer adhesives-applied rat intestine was 3.6 ± 0.3 at postoperative day 21, which was similar to that of the commercial anti-adhesives-applied group (3.6 ± 0.3) and lower than that of the control group (4.9 ± 0.5). These findings indicate that the double-layer patch (CHI-G/cHA) has the potential to effectively prevent both postoperative adhesions and anastomotic leakage, offering a promising solution for gastrointestinal surgery.

Single-port versus multiport robotic total mesorectal excision for rectal cancer: initial experiences by case-matched analysis of short-term outcomes.

Purpose: The da Vinci single-port (SP) system has been used in various surgical fields, including colorectal surgery. However, limited experience has been reported on its safety and feasibility. This study aims to evaluate the short-term outcomes of SP robotic surgery for the treatment of rectal cancer compared with multiport (MP) robotic surgery. Methods: Rectal cancer patients who underwent curative resection in 2020 were reviewed. A total of 43 patients underwent robotic total mesorectal excision (TME), of which 26 (13 in each group, SPTME vs. MPTME) were included in the case-matched cohort for analysis. Intraoperative and postoperative outcomes and pathological results were compared between the 2 groups. Results: Median tumor height was similar between the 2 groups (SPTME vs. MPTME: 5.9 cm [range, 2.2-9.6 cm] vs. 6.7 cm [range, 3.4-10.0 cm], P = 0.578). Preoperative chemoradiotherapy was equally performed (38.5%). The median estimated blood loss was less (20.0 mL [range, 5.0-20.0 mL] vs. 30.0 mL [range, 20.0-30.0 mL], P = 0.020) and the median hospital stay was shorter (7 days [range, 6-8 days] vs. 8 days [range, 7-9 days], P = 0.055) in the SPTME group. Postoperative complications did not differ (SPTME vs. MPTME: 7.7% vs. 23.1%, P = 0.587). One patient in the SPTME group and 3 in the MPTME group experienced anastomotic leakage. Conclusion: SP robotic TME showed perioperative outcomes similar to MP robotic TME. The SP robotic system can be considered a surgical option for the treatment of rectal cancer. Further prospective randomized trials with larger cohorts are required.

Short-term outcomes of Early versus conventional adjuvant chemotherapy in stage III colon cancer: randomized clinical trial.

BACKGROUND: Evidence is lacking regarding the earliest timing of initiating adjuvant chemotherapy to maximize its efficacy safely. A trial was designed and conducted to evaluate the safety and oncological efficacy of early adjuvant chemotherapy compared with conventional adjuvant chemotherapy. The short-term outcomes are reported here. METHODS: A multicentre, randomized (1 : 1), open-label, phase III trial was conducted comparing early adjuvant chemotherapy with conventional adjuvant chemotherapy in patients with stage III colon cancer. Patients who underwent radical surgery who had stage III colon cancer confirmed by histopathological assessment were screened and randomized into the early adjuvant chemotherapy arm or the conventional adjuvant chemotherapy arm. The primary endpoint was 3-year disease-free survival. The adjuvant chemotherapy with FOLFOX was delivered between postoperative day 10 and 14 in the early adjuvant chemotherapy arm, and between postoperative day 24 and 28 in the conventional adjuvant chemotherapy arm. Toxicity and quality of life were evaluated. RESULTS: Between 9 September 2011 and 6 March 2020, 443 patients consented to randomization at eight sites. The intention-to-treat population included 423 patients (209 in the early adjuvant chemotherapy arm and 214 in the conventional adjuvant chemotherapy arm), and the safety population included 380 patients (192 in the early adjuvant chemotherapy arm and 188 in the conventional adjuvant chemotherapy arm). There was no statistically significant difference in overall toxicity (28.1 per cent in the early adjuvant chemotherapy arm and 28.2 per cent in the conventional adjuvant chemotherapy arm, P = 0.244), surgical complications, and quality of life between the two arms. CONCLUSION: Adjuvant chemotherapy can be safely initiated 2 weeks after surgery with toxicity and quality of life comparable to conventional adjuvant chemotherapy for stage III colon cancer.

Single-Port Robotic Intersphincteric Resection for the Treatment of Rectal Cancer.

BACKGROUND: The da Vinci Single-port (SP) system is designed to facilitate single-incision robotic surgery in a narrow space. We developed a new procedure of intersphincteric resection (ISR) using the SP platform and evaluated the technical safety and feasibility of this procedure for the treatment of very low rectal cancer. MATERIALS AND METHODS: Eleven rectal cancer patients who underwent SP robotic ISR between August 2020 and July 2021 were included. Patients' clinical characteristics, operative and pathologic findings of the patients were retrospectively analyzed. RESULTS: The median tumor height was 3 cm (range, 2-4 cm). A single docking was performed, and the median docking time was 3 min 10 sec (range, 2 min 50 sec-3 min 30 sec). The median total operation time was 210 min (range, 150-280 min), and the median time of pelvic dissection was 57 min (range, 45-68 min). All patients presented with negative distal resection margins [median 1 cm (range, 0.5-2.0 cm)], and only one patient had less than 1mm of circumferential resection margin (0.9 mm). CONCLUSIONS: Our initial experience suggests that SP robotic ISR is safe and feasible.

Robotic and laparoscopic salvage lateral pelvic node dissection for the treatment of recurrent rectal cancer.

BACKGROUND: The lateral pelvic sidewall is a major site of local recurrence after radical resection of rectal cancer. Salvage lateral pelvic node dissection (LPND) may be the only way to eliminate recurrent lateral pelvic nodes (LPNs). This study aimed to describe the technical details of robotic and laparoscopic salvage LPND and assess the short-term clinical and oncological outcomes in patients with recurrent LPNs who underwent salvage LPND by a minimally invasive approach for curative intent. METHODS: Between September 2010 and 2019, 36 patients who underwent salvage surgery for LPN recurrence were retrospectively analyzed from a prospectively maintained database. Patients' characteristics, index operation, MRI findings, and perioperative and pathological outcomes were analyzed. RESULTS: Eleven and 14 patients underwent robotic and laparoscopic salvage LPND, respectively. Eight patients (32.0%) underwent a combined salvage operation for resectable extra-pelvic sidewall metastases. There were four cases of open-conversion during the laparoscopic approach due to uncontrolled bleeding of iliac vessels. In these patients, metastatic LPNs were suspected of iliac vessel invasion and were found to be larger in size (median 15 mm; range 12-20) than that in patients who underwent successful LPND using the minimally invasive approach (median 10 mm; range 5-20). The median number of metastatic LPNs and harvested LPNs was 1 (range 0-3) and 6 (range 1-16), respectively. Six patients (24.0%) experienced postoperative complications including lymphoceles and voiding difficulties. During the follow-up (median 44.6 months; range 24.0-87.7), eight patients developed recurrences, mainly the lung and para-aortic lymph nodes, and one patient developed pelvic sidewall recurrence after laparoscopic salvage LPND. The 3-year disease-free survival and overall survival after salvage LPND were 66.4% and 79.2%, respectively. CONCLUSIONS: Robotic and laparoscopic salvage LPND for recurrent LPNs are safe and feasible with favorable short-term surgical outcomes. However, the surgical approach should be carefully chosen in patients with large-sized and invasive recurrent LPNs.

Clinical Importance of Prophylactic Ligation of the Bridging Vein in Acute Subdural Hematoma: A Case Report.

Acute subdural hematoma (ASDH) induced by a bridging vein (BV) rupture is considered a catastrophic head injury, especially in the elderly. Epidemiological studies have shown a much higher incidence rate of BV-induced ASDH in the elderly compared to younger adults, along with elevated morbidity and mortality, and poor outcomes. Brain atrophy can be a risk factor contributing to the increased risk of ASDH in elderly trauma patients. Considering this, prophylactic ligation of the impending breakage in the BV may reduce the risk of rebleeding and treat the ASDH. Here, we report a relevant case.

Efficacy of air leak test in detection of anastomotic leaks after rectal excision: a retrospective case-controlled study.

Purpose: Although its efficacy is uncertain, an intraoperative air leak test (ALT) is commonly used to detect mechanical defects following bowel anastomosis. This study aimed to evaluate the efficacy of ALT to detect anastomotic leakage (AL) following rectal excision. Methods: We reviewed our database for patients with rectal cancers who had undergone curative surgery between January 2012 and January 2018. Patients were grouped according to whether or not an ALT was performed. Propensity score analyses were performed to compare outcomes for groups in a 1:1 case-matched cohort. Results: In total, 1,191 patients underwent rectal excision; 438 (219 in each group) formed the case-matched cohort for analysis. The protective stoma rate was 16.0% and 14.6% in the ALT and the no-ALT groups, respectively (P = 0.791). In the ALT group, 2 patients (0.9%) showed a positive result and were treated with rectal tube drainage, resulting in no leakage. There was no significant difference in postoperative AL rate between the groups (ALT group: 4.6% vs. no-ALT group: 4.1%, P > 0.999). Conclusion: ALT played a minimal role in detecting AL following rectal excision. Further studies are warranted to validate our results and clarify whether AL can be prevented with ALT or alternative methods.

PIK3CA Mutations as a Prognostic Factor in Patients With Residual Rectal Cancer After Neoadjuvant Chemoradiotherapy.

BACKGROUND/AIM: PIK3CA mediates various cellular processes, such as transformation, tumor initiation and proliferation, and resistance to apoptosis. This study was conducted to identify the clinical significance and prognostic effect of PIK3CA mutations in patients with residual rectal cancer who underwent surgery after neoadjuvant chemoradiotherapy (NACRT). PATIENTS AND METHODS: Formalin-fixed and paraffin-embedded surgical specimens were collected from 128 patients between January 2006 and December 2011 and analyzed using real-time polymerase chain reaction for hotspot mutations in exons 9 and 20 of the PIK3CA gene. RESULTS: Of the 128 patients, 109 were analyzed and 19 were excluded because of poor DNA quality. Mutations in PIK3CA were identified in three patients (2.8%), all of which were detected in exon 20 of the PIK3CA gene. PIK3CA mutations significantly correlated with lymphatic invasion (p=0.016), lymph node metastasis (p=0.034), and higher pathological disease stage (p=0.040). By univariate analysis, patients with PIK3CA mutations were observed to have significantly shorter cancer-specific survival (CSS) (p=0.001) and disease-free survival (DFS) (p=0.006) than PIK3CA wild-type patients. However, PIK3CA mutations were not an independent prognostic factor for CSS (p=0.319) or DFS (p=0.219) in multivariate modeling. CONCLUSION: Our findings indicate that PIK3CA mutation plays a role in oncogenesis in rectal cancer and may be considered as a candidate therapeutic approach targeting the PIK3/Akt/mTOR pathway in patients with residual rectal cancer after NACRT.

Carbon black-containing self-healing adhesive hydrogels for endoscopic tattooing.

Endoscopic tattooing with India ink is a popular method for identifying colonic lesions during minimally invasive surgery because it is highly challenging to localize lesions during laparoscopy. However, there is a perceived unmet need for the injection of India ink and carbon particle suspension due to various complications and inconstant durability during the perioperative period. In this study, carbon black-containing self-healing adhesive alginate/polyvinyl alcohol composite hydrogels were synthesized as endoscopic tattooing inks. Alginate (Alg) conjugated with phenylboronic acid (PBA) groups in the backbone was crosslinked with polyvinyl alcohol (PVA) because of the dynamic bonds between the phenylboronic acid in alginate and the cis-diol groups of PVA. The carbon black-incorporated Alg-PBA/PVA hydrogels exhibited self-healing and re-shapable properties, indicating that improved intraoperative localization could be achieved. In addition, the adhesive tattooing hydrogels were stably immobilized on the target regions in the intraperitoneal spaces. These carbon black-containing self-healing adhesive hydrogels are expected to be useful in various surgical procedures, including endoscopic tattooing.

Effect of Defects in Graphene/Cu Composites on the Density of States.

The process of handling and bonding copper (Cu) and graphene inevitably creates defects. To use graphene/Cu composites as electronic devices with new physical properties, it is essential to evaluate the effect of such defects. Since graphene is an ultrathin anisotropic material having a hexagonal structure, an evaluation of graphene/Cu composites containing defects was conducted taking into account the inherent structural characteristics. The purpose of this study is to evaluate defects that may occur in the manufacturing process and to present a usable basic method for the stable design research and development of copper/graphene composites essential for commercialization of copper/graphene composites. In the future, when performing analytical calculations on various copper/graphene composites and defect shapes in addition to the defect conditions presented in this paper, it is considered that it can be used as a useful method considering defects that occur during application to products of desired thickness and size. Herein, density functional theory was used to evaluate the behavior of graphene/Cu composites containing defects. The density of states (DOS) values were also calculated. The analysis was implemented using three kinds of models comprising defect-free graphene and two- and four-layered graphene/Cu composites containing defects. DOS and Fermi energy levels were used to gage the effect of defects on electrical properties.

Comparison of Laparoscopic Versus Robot-Assisted Surgery for Rectal Cancers: The COLRAR Randomized Controlled Trial.

OBJECTIVE: To evaluate whether robotic for middle or low rectal cancer produces an improvement in surgical outcomes compared with laparoscopic surgery in a randomized controlled trial (RCT). BACKGROUND: There is a lack of proven clinical benefit of robotic total mesorectal excision (TME) compared with a laparoscopic approach in the setting of multicenter RCTs. METHODS: Between July 2011 and February 2016, patients diagnosed with an adenocarcinoma located <10 cm from the anal verge and clinically rated T1-4aNxM0 were enrolled. The primary outcome was the completeness of TME assessed by a surgeon and a pathologist. RESULTS: The RCT was terminated prematurely because of poor accrual of data. In all, 295 patients were assigned randomly to a robot-assisted TME group (151 in R-TME) or a laparoscopy-assisted TME group (144 in L-TME). The rates of complete TME were not different between groups (80.7% in R-TME, 77.1% in L-TME). Pathologic outcomes including the circumferential resection margin and the numbers of retrieved lymph nodes were not different between groups. In a subanalysis, the positive circumferential resection margin rate was lower in the R-TME group (0% vs 6.1% for L-TME; P =0.031). Among the recovery parameters, the length of opioid use was shorter in the R-TME group ( P =0.028). There was no difference in the postoperative complication rate between the groups (12.0% for R-TME vs 8.3% for L-TME). CONCLUSIONS: In patients with middle or low rectal cancer, robotic-assisted surgery did not significantly improve the TME quality compared with conventional laparoscopic surgery (ClinicalTrial.gov ID: NCT01042743).

Oncological impact of intraperitoneal chemotherapy after cytoreductive surgery for patients with colorectal peritoneal metastasis: A bi-institutional retrospective analysis.

BACKGROUND AND OBJECTIVES: There is a paucity of evidence on the value of intraperitoneal chemotherapy (IPC) following cytoreductive surgery (CRS) for colorectal peritoneal metastasis. This study aimed to evaluate the association between mitomycin C-IPC and survival outcomes following CRS. METHODS: The institutional databases of two tertiary hospitals were reviewed to identify patients who underwent CRS for colorectal peritoneal metastasis. The outcomes of patients who underwent CRS without IPC were compared with those of patients who underwent CRS plus early postoperative intraperitoneal chemotherapy (EPIC) or CRS plus hyperthermic intraperitoneal chemotherapy (HIPEC). The primary endpoints were cancer-specific survival (CSS), progression-free survival (PFS), and peritoneal PFS (P-PFS). RESULTS: In 149 patients with peritoneal metastasis alone, EPIC and HIPEC use was significantly associated with better CSS, PFS, and P-PFS in the multivariate analysis. CSS was also significantly associated with perioperative systemic chemotherapy. Among 42 patients with both peritoneal and extraperitoneal metastases, CSS was independently related to the completeness of cytoreduction score, location of extraperitoneal metastasis, and grade 3-4 complications. CONCLUSIONS: Mitomycin C-IPC after CRS was associated with better survival outcomes than CRS alone in patients with resectable peritoneal metastasis of colorectal cancer. This study found that IPC had beneficial effects regarding P-PFS in patients with both peritoneal and extraperitoneal metastases.

Anastomotic leak after minimally invasive anterior resection for rectal cancer with high versus low ligation of the inferior mesenteric artery: a study protocol for a multicentre randomized clinical trial.

BACKGROUND: Although many efforts have been made to decrease the incidence of anastomotic leak (AL), it remains one of the most serious complications of rectal cancer surgery. Many previous studies have reported an association between the ligation level of the inferior mesenteric artery (IMA) (high or low) and the incidence of AL after rectal cancer surgery. However, we cannot draw a solid conclusion because of the low quality and heterogeneity of those studies. Therefore, this study aims to investigate the impact of the IMA ligation level on the occurrence of AL after minimally invasive anterior resection of rectal cancer. METHODS/DESIGN: Patients with primary rectal cancer without distant metastases will be included after screening. They will be randomly assigned (1:1) to receive high or low ligation of the IMA. The primary endpoint is AL incidence; secondary endpoints are quality of life; urinary, sexual, and defecatory functions; and 3-year disease-free survival. We hypothesized that the incidence rate of AL would be 15% and 5% in the high- and low-ligation groups, respectively. With a two-sided α of 0.05 and a power of 0.8, the sample size is calculated to be 314 patients (157 per group), considering a 10% dropout rate. DISCUSSION: Although many studies have compared the short- and long-term outcomes of high and low ligation of the IMA in rectal cancer surgery, it is still debatable. This trial aims to help draw a more solid conclusion regarding the association between the IMA ligation level and AL incidence after rectal cancer surgery. We also hope to contribute to standardizing the method of rectal cancer surgery in this trial. TRIAL REGISTRATION: Clinical Research Information Service KCT0003523. Registered on February 18, 2019.

Comparison of the Analgesic Efficacy of Opioid-Sparing Multimodal Analgesia and Morphine-Based Patient-Controlled Analgesia in Minimally Invasive Surgery for Colorectal Cancer.

BACKGROUND: A multimodal analgesia (MMA) protocol has shown the effect of postoperative pain control and reduced the postoperative opioid consumption. However, it was questionable whether MMA could replace opioid-based patient-controlled analgesia (PCA) for postoperative pain control. Therefore, this study aimed to investigate whether an MMA protocol is non-inferior to opioid-based PCA for pain management after a minimally invasive colorectal cancer surgery. METHODS: A randomized, open-label, non-inferiority clinical trial was conducted on patients undergoing laparoscopic or robotic resection of colorectal cancer. The patients were randomly assigned to either the PCA or MMA group. The MMA protocol included pregabalin, tramadol, wound infiltration, and transversus abdominis plane block. The primary outcome was the numeric rating scale (NRS) score for pain at rest 24 h postoperatively. RESULTS: Ninety-seven patients were included in the intention-to-treat analysis. The mean difference in NRS score at rest at 24 h was 0.25 (95% confidence interval, - 0.61 to 1.11). This result demonstrated the non-inferiority of MMA to PCA in our non-inferiority margin (- 1). Compared with the PCA group, the median remifentanil dose (996 vs. 654 µg; p < 0.001) and time in the post-anesthesia care unit (35 vs. 25 min; p < 0.001) were significantly less in the MMA group. CONCLUSIONS: Our MMA protocol successfully controlled postoperative pain and was non-inferior to morphine-based PCA based on patient-reported pain intensity, with no significant increase in adverse events. These results will help construct a strategy to reduce conventional opioid prescriptions for pain management after a minimally invasive colorectal cancer surgery. Trial Registration Number Trial Registration Clinical Research Information Service Identifier: KCT0002593.