Effect of the lymphocyte-to-monocyte ratio on the prognosis of patients with obstructive colorectal cancer with a colonic stent: a retrospective multicenter study in Japan.

PURPOSE: The prognostic value of the lymphocyte-to-monocyte (LMR) ratio has been reported for various cancers, including colorectal cancer (CRC). The insertion of colonic stents is considered effective for patients with surgically indicated obstructive CRC, but their LMR can vary depending on factors such as inflammation associated with stent dilation and improvement of obstructive colitis. However, the usefulness of the LMR in patients with obstructive CRC and colonic stents and the optimal timing for its measurement remain unclear. We conducted this study to investigate the relationship between the pre-stent LMR and the mid-term prognosis of patients with obstructive CRC and stents as a bridge to surgery (BTS). METHODS: The subjects of this retrospective multicenter study were 175 patients with pathological stage 2 or 3 CRC. Patients were divided into a low pre-stent LMR group (n = 87) and a high pre-stent LMR group (n = 83). RESULTS: Only 3-year relapse-free survival differed significantly between the low and high pre-stent LMR groups (39.9% vs. 63.6%, respectively; p = 0.015). The pre-stent LMR represented a prognostic factor for relapse-free survival in multivariate analyses (hazard ratio 2.052, 95% confidence interval 1.242-3.389; p = 0.005), but not for overall survival. CONCLUSIONS: A low pre-stent LMR is a prognostic factor for postoperative recurrence in patients with obstructive CRC and a colonic stent as a BTS.

Risk factors for pulmonary complications after colorectal cancer surgery: a Japanese multicenter study.

PURPOSE: Pulmonary complications (PC) are a serious condition with a 20% mortality rate. However, few reports have examined risk factors for PC after colorectal surgery. This study investigated the frequency, characteristics, and risk factors for PC after colorectal cancer surgery. METHODS: Between January 2016 and December 2022, we retrospectively reviewed 3979 consecutive patients who underwent colorectal cancer surgery in seven participating hospitals. Patients were divided into patients who experienced PC (PC group, n = 54) and patients who did not (non-PC group, n = 3925). Clinical and pathological features were compared between groups. RESULTS: Fifty-four patients (1.5%) developed PC, of whom 2 patients (3.7%) died due to PC. Age was greater (80 years vs 71 years; p < 0.001), frequency of chronic obstructive pulmonary distress was greater (9.3% vs 3.2%; p = 0.029), performance status was poorer (p < 0.001), the proportion of underweight was higher (42.6% vs 13.4%, p < 0.001), frequency of open surgery was greater (24.1% vs 9.3%; p < 0.001), and blood loss was greater (40 mL vs 22 mL; p < 0.001) in the PC group. Multivariate analysis revealed male sex (odds ratio (OR) 2.165, 95% confidence interval (CI) 1.176-3.986; p = 0.013), greater age (OR 3.180, 95%CI 1.798-5.624; p < 0.001), underweight (OR 3.961, 95%CI 2.210-7.100; p < 0.001), and poorer ASA-PS (OR 3.828, 95%CI 2.144-6.834; p < 0.001) as independent predictors of PC. CONCLUSION: Our study revealed male sex, greater age, underweight, and poorer ASA-PS as factors associated with development of PC, and suggested that pre- and postoperative rehabilitation and pneumonia control measures should be implemented for patients at high risk of PC.

Short- and Long-term Outcomes After Colonic Stent Insertion as a Bridge to Surgery in Elderly Colorectal Cancer Patients.

BACKGROUND/AIM: Colonic stents have been inserted as a bridge to surgery in patients with resectable colorectal cancer, allowing bowel decompression for systemic assessment and better preparation to avoid stoma construction. However, reports of short- and long-term prognoses for elderly patients remain limited. PATIENTS AND METHODS: This retrospective study reviewed 175 consecutive patients who underwent colonic stent insertion for bowel obstruction followed by curative colectomy. Patients were divided into those >80 years old (Old, n=49) and those <80 years old (Young, n=126). After propensity score matching, 41 patients in each group matched. RESULTS: Before matching, performance status was poorer (p<0.001), postoperative complication rate was higher (p=0.009), adjuvant chemotherapy rate was lower (p<0.001), and hospital stay was longer (p<0.001) in the Old group. After matching, adjuvant chemotherapy rate was lower (9.8% vs. 39.0%; p=0.003) and hospital stay was longer (14 vs. 12 days; p=0.029) in the Old group. Five-year relapse-free survival (42.9% vs. 68.8%; p=0.200), overall survival (66.3% vs. 87.7%; p=0.081), and cancer-specific survival (68.2% vs. 87.7%; p=0.129) rates were comparable between groups. CONCLUSION: Colorectal resection after colonic stent insertion is useful for elderly patients, with potential to reduce postoperative complication rates and achieve good long-term results with appropriate case selection.

Risk factors for infection of totally implantable central venous access ports among patients requiring port removal.

BACKGROUND: Totally implantable central venous access ports, are required for various purposes, ranging from chemotherapy to nutrition. Port infection is a common complication. In many patients with port infection, the ports are removed because antibiotics are ineffective. We evaluated the risk factors associated with port removal due to port infection. METHODS: By retrospective chart review, we collected data of 223 patients who underwent port removal for any reason. Port infection was defined as infection symptoms, such as fever; elevated white blood cell counts or C-reactive protein levels; or redness at the port site, in the absence of other infections, which improved with port removal. The characteristics of patients with or without port infection were compared using univariate (chi-squared test, t-test) and multivariate logistic regression analyses. RESULTS: We compared 172 patients without port infection to 51 patients with port infection. Univariate analysis identified sex (p = 0.01), body mass index (BMI) ⩽20 kg/m2 (p = 0.00004), diabetes mellitus (p = 0.04), and purpose of use (p = 0.0000003) as significant variables. However, male sex (p = 0.03, 95% confidence interval [CI]: 0.01-0.23), BMI ⩽20 kg m2 (p = 0.002, 95% CI: 0.06-0.29), and purpose of use (total parenteral nutrition (TPN); p = 0.000005, 95% CI: 0.31-0.76) remained significant using multivariate analysis. Moreover, the patients with short bowel syndrome and difficulty in oral intake tended to be infected easily. Additionally, Staphylococcus species were the most common microbes involved in port infection. CONCLUSIONS: Male sex, BMI ⩽20 kg/m2, and purpose of use as a TPN were risk factors for port infection. Ports should not be used for long duration of TPN or used only in exceptional cases.

Impact of institutional volume on short- and long-term outcomes after laparoscopic colectomy.

INTRODUCTION: The impact of institutional volume on postoperative outcomes after laparoscopic colectomy is still being debated. This study aimed to investigate whether differences in postoperative outcomes of laparoscopic colon resection exist between high- and low-volume centers. METHODS: Data were reviewed for 1360 patients who underwent laparoscopic colectomy for colon cancer between 2016 and 2022. Patients were divided according to whether they were treated at a high-volume center (≥100 colorectal surgeries annually; n = 947) or a low-volume center (<100 colorectal surgeries annually; n = 413). Propensity score matching was applied to balance covariates and minimize selection biases that could affect outcomes. Finally, 406 patients from each group were matched. RESULTS: After matching, patients from high-volume centers showed a higher number of retrieved lymph nodes (19 vs. 17, p < .001) and more frequent involvement of expert surgeons (98.3% vs. 88.4%, p < .001). Postoperative complication rates were similar between groups (p = .488). No significant differences between high- and low-volume centers were seen in relapse-free survival (88.8% each, p = .716) or overall survival (85.7% vs. 82.8%, p = .480). CONCLUSION: The present study suggests that in appropriately educated organizations, relatively safe procedures and good prognosis may be obtained for laparoscopic colectomy cases, regardless of institutional volume.

Prognostic value of lymph node distribution after laparoscopic colectomy with Japanese D3 dissection.

PURPOSE: Positive pathologic lymph nodes in colorectal cancer represent an important prognostic indicator. Whether lymph node distribution or the number of metastatic nodes is more strongly associated with survival prediction remains controversial. METHODS: Among 3449 colorectal cancer surgeries performed at Nagasaki University Hospital and five affiliated institutions from April 2016 to March 2022, we investigated 604 patients who underwent laparoscopic radical resection and were diagnosed with pathological stage III cancer. Patients were divided into two groups according to whether they had central vessel metastasis (LND3 group, n=42) or not (LND1/2 group, n=562). After adjusting for background factors using propensity score matching, the LND3 group included 42 patients and the LND1/2 group included 40 patients. Patient background characteristics and prognosis were compared between these two groups. RESULTS: Before matching, frequencies of right-side colon cancer (64.3% vs 38.1%, p=0.001), multivisceral resection (11.9% vs 4.4%, p=0.039), clinical N2 status (40.5% vs 22.6%, p=0.032), and pathological N2 (73.8% vs 22.6%, p<0.001) were all greater, and the number of lymph nodes retrieved was higher (24 vs 19, p=0.042) in the LND3 group. After matching, no differences in any clinical factors were evident between groups. Five-year RFS (44.8% vs 77.1%, p=0.004) and OS (43.1% vs 83.2%, p<0.001) were worse in the LND3 group. Adjuvant chemotherapy improved RFS (adjuvant chemotherapy (+) vs adjuvant chemotherapy (-): 62.1% vs 27.7%, p=0.047) in the LND3 group. CONCLUSION: LND3-positive patients show poorer prognosis than LND1/2 patients and should be treated with an appropriate perioperative treatment strategy.

Short-term outcomes after laparoscopic colorectal cancer surgery in patients over 90 years old: a Japanese multicenter study.

BACKGROUND: The effect of laparoscopic surgery on short-term outcomes in colorectal cancer patients over 90 years old has remained unclear. METHODS: We reviewed 87 colorectal cancer patients aged over 90 years who underwent surgery between 2016 and 2022. Patients were divided into an open surgery group (n = 22) and a laparoscopic surgery group (n = 65). The aim of this study was to investigate the effect of laparoscopic surgery on postoperative outcome in elderly colorectal cancer patients, as compared to open surgery. RESULTS: Seventy-eight patients (89.7%) had comorbidities. Frequency of advanced T stage was lower with laparoscopic surgery (p = 0.021). Operation time was longer (open surgery 146 min vs. laparoscopic surgery 203 min; p = 0.002) and blood loss was less (105 mL vs. 20 mL, respectively; p < 0.001) with laparoscopic surgery. Length of hospitalization was longer with open surgery (22 days vs. 18 days, respectively; p = 0.007). Frequency of infectious complications was lower with laparoscopic surgery (18.5%) than with open surgery (45.5%; p = 0.021). Multivariate analysis revealed open surgery (p = 0.026; odds ratio, 3.535; 95% confidence interval, 1.159-10.781) as an independent predictor of postoperative infectious complications. CONCLUSIONS: Laparoscopic colorectal resection for patients over 90 years old is a useful procedure that reduces postoperative infectious complications.

Correlations of age with clinicopathological features, perioperative outcomes and the prognosis in patients with colorectal cancer: a Japanese multicenter study.

PURPOSE: Colorectal cancer is not common in patients under 40 years old, and its associations with clinical features and the prognosis remain uncertain. METHODS: Using a multicenter database, we retrospectively reviewed 3015 patients who underwent colorectal surgery between 2016 and 2021. Patients were divided by age into those < 40 years old (young; n = 52), 40-54 years old (middle-aged; n = 254) and > 54 years old (old; n = 2709). We then investigated age-related differences in clinicopathological features, perioperative outcomes and the prognosis. RESULTS: The proportion of young patients increased annually from 0.63% in 2016 to 2.10% in 2021. Female patients were more frequent, the performance status was better, tumors were larger, clinically node-positive and poorly differentiated adenocarcinomas were more frequent, postoperative complications were less frequent, and the hospital stay was shorter in young patients than in older patients. Young age was an independent predictor of a low risk of postoperative complications (odds ratio, 0.204; 95% confidence interval, 0.049-0.849; p = 0.028). With pathologically node-positive status, adjuvant chemotherapy was more frequent in young patients (100%) than in middle-aged (73.7%) or old (51.8%) patients (p < 0.001), and the 3-year relapse-free survival was better in the young group than in others. CONCLUSION: Despite higher rates of advanced tumors in younger patients, adequate adjuvant chemotherapy appears to improve the relapse-free survival.

Risk factors for reoperation within 30 days in laparoscopic colorectal cancer surgery: A Japanese multicenter study.

INTRODUCTION: Thirty-day reoperation rate reflects short-term surgical outcomes following surgery. Laparoscopic surgery for colorectal cancer reportedly has positive effects on postoperative complications. This retrospective study investigated risk factors for 30-day reoperation rate among patients after laparoscopic colorectal cancer surgery using a multicenter database. METHODS: Participants comprised 3037 patients who had undergone laparoscopic resection of colorectal cancer between April 2016 and December 2022 at the Nagasaki University and six affiliated centers, classified into those who had undergone reoperation within 30 days after surgery (RO group; n = 88) and those who had not (NRO group; n = 2949). Clinicopathological characteristics were compared between groups. RESULTS: In the RO group, anastomotic leakage occurred in 57 patients (64.8%), intestinal obstruction in 12 (13.6%), and intraabdominal abscess in 5 (5.7%). Female patients were more frequent, preoperative treatment less frequent, body mass index (BMI) lower, operation time longer, blood loss greater, and hospital stay longer in the RO group (p < .05 each). Multivariate analysis revealed BMI (odds ratio, 0.415; 95% confidence interval, 0.218-0.787; p = .021) and poor performance status (odds ratio, 1.966; 95% confidence interval, 1.106-3.492; p = .021) as independent predictors of reoperation. CONCLUSION: Perioperative measures are warranted for patients with low BMI and poor performance status undergoing laparoscopic colorectal surgery.

Incidence of and risk factors for postoperative ileus between right and left laparoscopic colectomy using propensity-score-matched analysis: A retrospective multicenter study.

INSTRUCTION: In colon cancer, the incidence of postoperative ileus is reportedly higher for the right-side than for the left-side colon, but those studies included small numbers of subjects and contained several biases. Furthermore, risk factors for postoperative ileus remain unclear. METHODS: This multicenter study reviewed 1986 patients who underwent laparoscopic colectomy between 2016 and 2021 for right-side (n = 907) and left-side (n = 1079) colon cancer. After propensity score matching, 803 patients in each group were matched. RESULTS: Postoperative ileus occurred in 97 patients. Before matching, the proportion of female patients and median age were higher and frequency of preoperative stent insertion was lower with right colectomy (P < .001 each). After matching, the number of retrieved lymph nodes (17 vs 15, P < .001) and greater rates of undifferentiated adenocarcinoma (10.6% vs 5.1%, P < .001) and postoperative ileus (6.4% vs 3.2%, P = .004) were higher in right colectomy. Multivariate analysis revealed male gender (hazard ratio, 1.798; 95% confidence interval, 1.049-3.082; P = .32) and history of abdominal surgery (hazard ratio, 1.909; 95% confidence interval, 1.073-3.395; P = .027) as independent predictors of postoperative ileus in right-side colon cancer. CONCLUSION: This study revealed a higher risk of postoperative ileus after right colectomy with laparoscopic surgery. Male gender and history of abdominal surgery were risk factors for postoperative ileus after right colectomy.

Usefulness of the endoscopic surgical skill qualification system for laparoscopic colectomy for transverse colon cancer: a Japanese multicenter analysis.

PURPOSE: Laparoscopic colectomy for transverse colon cancer (TCC) can be technically demanding due to the anatomical complexity of the region. In Japan, the Endoscopic Surgical Skill Qualification System (ESSQS) was established to improve the skill of laparoscopic surgeons and further develop surgical teams. We examined the safety and feasibility of laparoscopic colectomy for TCC and evaluated the effects of the Japanese ESSQS in facilitating this approach. METHODS: We retrospectively reviewed 136 patients who underwent laparoscopic colectomy for TCC between April 2016 and December 2021. Patients were divided into an ESSQS-qualified surgeon group (surgery performed by an ESSQS-qualified surgeon, n = 52) and a non ESSQS-qualified surgeon (surgery performed by a non ESSQS-unqualified surgeon, n = 84). Clinicopathological and surgical features were compared between groups. RESULTS: Postoperative complications occurred in 37 patients (27.2%). The proportion of patients who developed postoperative complications was lower in the ESSQS-qualified surgeon group (8.0%) than that in the non ESSQS-qualified surgeon group (34.5%; p < 0.017). Multivariate analysis revealed "Operation by ESSQS-qualified surgeon surgeon" (odds ratio (OR) 0.360, 95% confidence interval (CI) 0.140-0.924; p = 0.033), blood loss (OR 4.146, 95% CI 1.688-10.184; p = 0.002), and clinical N status (OR 4.563, 95% CI 1.814-11.474; p = 0.001) as factors independently associated with postoperative complications. CONCLUSION: The present multicenter study confirmed the feasibility and safety of laparoscopic colectomy for TCC and revealed that ESSQS-qualified surgeon achieved better surgical outcomes.

Adipose-Derived Mesenchymal Stem Cells Attenuate Immune Reactions Against Pig Decellularized Bronchi Engrafted into Rat Tracheal Defects.

Decellularized scaffolds are promising biomaterials for tissue and organ reconstruction; however, strategies to effectively suppress the host immune responses toward these implants, particularly those without chemical crosslinking, remain warranted. Administration of mesenchymal stem cells is effective against immune-mediated inflammatory disorders. Herein, we investigated the effect of isogeneic abdominal adipose-derived mesenchymal stem/stromal cells (ADMSCs) on xenogeneic biomaterial-induced immunoreactions. Peripheral bronchi from pigs, decellularized using a detergent enzymatic method, were engrafted onto tracheal defects of Brown Norway (BN) rats. BN rats were implanted with native pig bronchi (Xenograft group), decellularized pig bronchi (Decellularized Xenograft), or Decellularized Xenograft and ADMSCs (Decellularized Xenograft+ADMSC group). In the latter group, ADMSCs were injected intravenously immediately post implantation. Harvested graft implants were assessed histologically and immunohistochemically. We found that acute rejections were milder in the Decellularized Xenograft and Decellularized Xenograft+ADMSC groups than in the Xenograft group. Mild inflammatory cell infiltration and reduced collagen deposition were observed in the Decellularized Xenograft+ADMSC group. Additionally, ADMSC administration decreased CD8+ lymphocyte counts but increased CD163+ cell counts. In the Decellularized Xenograft+ADMSC group, serum levels of vascular endothelial growth factor and IL-10 were elevated and tissue deposition of IgM and IgG was low. The significant immunosuppressive effects of ADMSCs illustrate their potential use as immunosuppressive agents for xenogeneic biomaterial-based implants.

Efficacy of left colic artery preservation with D3 lymph node dissection in laparoscopic surgery for advanced sigmoid and rectal cancer.

PURPOSE: For advanced left colon cancer, lymph node dissection at the root of the inferior mesenteric artery is recommended. Whether the left colic artery (LCA) should be preserved or resected remains contentious. METHODS: The 367 patients who underwent laparoscopic sigmoidectomy or anterior resection and who were pathologically node-positive were reviewed. Patients were divided into LCA-preserving group (LCA-P, n = 60) and LCA-non-preserving group (LCA-NP, n = 307). Propensity score matching was applied to minimize selection bias and 59 patients were matched. RESULTS: Before matching, the rates of poor performance status and cardiovascular disease were higher in the LCA-P group (p < 0.001). After matching, operation time was longer (276 vs. 240 min, p = 0.001), the frequency of splenic flexure mobilization (62.7% vs. 33.9%, p = 0.003) and lymphovascular invasion (84.7% vs. 55.9%, p = 0.001) was higher in the LCA-P group. Severe postoperative complications (CD ≥ 3) occurred only in the LCA-NP group (0% vs. 8.4%, p = 0.028). The median follow-up period was 38.5 months (range 2.0-70.0 months). The 5-year RFS rates (67.8% vs. 66.0%, p = 0.871) and OS rates (80.4% vs. 74.9%, p = 0.308) were comparable between the groups. CONCLUSIONS: Laparoscopic LCA-sparing surgery for left-sided colorectal cancer reduces the risk of severe complications and offers a favorable long-term prognosis.

Effect of adjuvant chemotherapy after curative resection of colorectal cancer peritoneal metastasis.

PURPOSE: Several guidelines have recommended surgical resection for localized peritoneal metastases, but the prognosis remains poor. In addition, the efficacy of adjuvant chemotherapy (AC) after curative resection is under debate. The present study compared long-term outcomes between curative and non-curative resection and evaluated the effects of AC after curative resection. METHODS: Using a multicenter database, we retrospectively reviewed 123 colorectal cancer patients with peritoneal metastases between April 2016 and December 2021. Of these patients, 49 underwent curative resection, and 74 underwent non-curative resection. RESULTS: The frequency of broad metastases was lower in the curative resection group (8.2%) than in the non-curative resection group (43.2%, p < 0.001). Among all patients, 5-year overall survival rate was higher in the curative resection group (43.0%) than in the non-curative resection group (7.3%, p = 0.004). Among patients who underwent curative resection, 5-year overall survival rate was significantly higher in the AC group (48.2%) than in the non-AC group (38.1%, p = 0.037). Multivariate analysis of all patients revealed pathological N status and non-curative resection as independent predictors of overall survival. In patients who underwent curative resection, advanced age was an independent predictor of relapse-free survival, and AC was an independent predictor of overall survival. CONCLUSION: This multicenter study of colorectal cancer patients with peritoneal metastases revealed that prognosis was more favorable for curable cases than for non-curable cases. Prognosis was more favorable in the AC group than in the non-AC group after curative resection.

Impacts of trans-anal tube placement in patients with sigmoid colon cancer: Risk verification analysis using inverse probability weighting analysis.

Purpose: Anastomotic leakage (AL) is a serious postoperative complication that affects short- and long-term outcomes. The use of a trans-anal drainage tube (TDT) is reported to prevent AL in rectal cancer patients, but its value in sigmoid colon cancer patients is unknown. Methods: Admitted to the study were 379 patients who underwent surgery for sigmoid colon cancer between 2016 and 2020. Patients were divided into two groups according to the placement (n = 197) or nonplacement of a TDT (n = 182). To determine the factors affecting the association between TDT placement and AL, we estimated average treatment effects by stratifying each factor using the inverse probability of treatment weighting method. The association between prognosis and AL was evaluated in each identified factor. Results: Factors associated with postsurgical insertion of a TDT were advanced age, male sex, high body mass index (BMI), poor performance status, and presence of comorbidities. TDT placement was associated with a significantly lower AL in male patients (odds ratio [OR], 0.22; 95% confidence interval [CI], 0.07-0.73; P = .013) and for BMI ≥ 25 kg/m2 (OR, 0.13; 95% CI, 0.02-0.65; P = .013). In addition, there was a significant association of AL with poor prognosis in patients with BMI ≥ 25 kg/m2 (P = .043), age > 75 y (P = .021), and pathological node-positive disease (P = .015). Conclusion: Sigmoid colon cancer patients with BMI ≥ 25 kg/m2 are the most appropriate candidates for postoperative TDT insertion, in terms of reduced incidence of AL and improved prognosis.

Effect of oxaliplatin in elderly colon cancer patients with pathological T4 and/or N2 disease: a multicenter, propensity score-matched analysis.

PURPOSE: Although adjuvant chemotherapy (AC) using fluoro-pyrimidine and oxaliplatin (FU + oxaliplatin) is recommended after curative resection for locally advanced colon cancer patients, several randomized controlled trials have shown no additional effect of oxaliplatin in patients aged ≥ 70 years. Here, we examined the effectiveness of FU + oxaliplatin on the long-term outcome of old patients with a high risk of recurrence. METHODS: This multicenter, retrospective study included 346 colon cancer patients diagnosed with pathological T4 and/or N2 disease from 2016 to 2020. They were divided into an old group (≥ 70 years, n = 197) and a young group (< 70 years, n = 167). Propensity score matching was used to minimize selection bias, and 126 patients per group were matched. RESULTS: Before matching, the rates of poor performance status (p < 0.001) and the presence of comorbidities (76.1% vs. 47.9%, p < 0.001) were higher in the old group. Although all baseline factors were similar between groups, after matching, the AC rate was lower in the old group (45.2% vs. 65.1%, p = 0.002). In the old group, relapse-free (82.2% vs. 55.6% and 69.6%, p < 0.05) and overall survival (83.1% vs. 80.0% and 44.4%, p < 0.05) rates were significantly higher in the AC patients with FU + oxaliplatin than in the AC patients with only FU and the non-AC patients. CONCLUSION: The selected old colon cancer patients with a high risk of recurrence gained an additional benefit with respect to prognosis from FU + oxaliplatin as AC.

Short- and long-term outcomes of single-incision laparoscopic surgery for right colon cancer: A multicenter propensity score-matched analysis.

INTRODUCTION: Single-incision laparoscopic surgery (SILS) for colon cancer is a recent innovation in minimally invasive surgery that can improve short-term outcome. However, several biases exist in current favorable comparisons of SILS with conventional laparoscopic (CL) surgery. Moreover, the oncological outcomes in SILS remain unclear. The aim of this study was to identify outcomes following SILS and CL for right colectomy using a propensity score-matched analysis. METHODS: A total of 553 patients underwent curative resection for right colon cancer (58 SILS and 495 CL). After propensity score matching, 58 patients in each group were matched. RESULTS: Before matching, median age was younger (p = 0.037) and clinical stage was lower (p < 0.001) in the SILS group. After matching, operation time was shorter (172 versus 193 min, p = 0.007) and blood loss was less (12 versus 20 mL, p = 0.037) in the SILS group. Most of the SILS cases were performed (43.1%) or supervised (51.7%) by an expert surgeon. Median follow-up duration was 30 and 37 mo in the SILS and CL groups, respectively. Three-year relapse-free survival was 92.5% and 92.4% (p = 0.781); and overall survival was 100% versus 98.1% (p = 0.177). CONCLUSIONS: Under the control of expert surgeons, SILS appeared to be a safe and feasible approach and had similar oncological outcomes compared with CL in a propensity score-matched cohort of patients with right-sided colon cancer.

Transanal approach after preoperative imatinib treatment of a rectal gastrointestinal stromal tumors with external anal sphincter invasion: A case report.

INTRODUCTION AND IMPORTANCE: Rectal gastrointestinal stromal tumors (GISTs) are rare, and preserving anorectal function can be challenging. We report the case of a patient with rectal GIST with external anal sphincter invasion, treated via the laparoscopic and transanal approaches. CASE PRESENTATION: A 61-year-old man with locally advanced GIST in the right anterolateral wall of the lower rectum was examined. Lower endoscopy revealed a 50-mm submucosal tumor located 4 cm from the anal verge. On immunohistochemistry, the biopsy specimen tested positive for CD34 and C-KIT, and the patient was diagnosed with GIST. Abdominal magnetic resonance imaging (MRI) revealed external anal sphincter infiltration. Because of the large tumor size and proximity to the anal verge, preserving the anus was challenging, and colorectal resection was avoided. Instead, neoadjuvant therapy with imatinib was administered to facilitate local resection of the tumor. Post-treatment MRI showed a reduction in tumor size (30 × 20 × 30 mm), and surgery was performed. We identified an appropriate resection line for diplomatic sphincter resection of the infiltrated area by laparoscopy alone. Thus, we performed a hybrid surgery using the laparoscopic and transanal approaches. The patient had an unremarkable postoperative course and was discharged on postoperative day 23. CLINICAL DISCUSSION: No study has reported cases of rectal GIST with external anal sphincter invasion wherein anal function was preserved. Here, imatinib was administered preoperatively, and hybrid surgery was performed using the transanal and laparoscopic approaches. CONCLUSION: Preoperative treatment and surgery preserved anorectal function in a patient with a massive rectal GIST.

A new method using a vessel-sealing system provides coagulation effects to various types of bleeding with less thermal damage.

BACKGROUND: Hemostasis is very important for a safe surgery, particularly in endoscopic surgery. Accordingly, in the last decade, vessel-sealing systems became popular as hemostatic devices. However, their use is limited due to thermal damage to organs, such as intestines and nerves. We developed a new method for safe coagulation using a vessel-sealing system, termed flat coagulation (FC). This study aimed to evaluate the efficacy of this new FC method compared to conventional coagulation methods. METHODS: We evaluated the thermal damage caused by various energy devices, such as the vessel-sealing system (FC method using LigaSure™), ultrasonic scissors (Sonicision™), and monopolar electrosurgery (cut/coagulation/spray/soft coagulation (SC) mode), on porcine organs, including the small intestine and liver. Furthermore, we compared the hemostasis time between the FC method and conventional methods in the superficial bleeding model using porcine mesentery. RESULTS: FC caused less thermal damage than monopolar electrosurgery's SC mode in the porcine liver and small intestine (liver: mean depth of thermal damage, 1.91 ± 0.35 vs 3.37 ± 0.28 mm; p = 0.0015). In the superficial bleeding model, the hemostasis time of FC was significantly shorter than that of electrosurgery's SC mode (mean, 19.54 ± 22.51 s vs 44.99 ± 21.18 s; p = 0.0046). CONCLUSION: This study showed that the FC method caused less thermal damage to porcine small intestine and liver than conventional methods. This FC method could provide easier and faster coagulation of superficial bleeds compared to that achieved by electrosurgery's SC mode. Therefore, this study motivates for the use of this new method to achieve hemostasis with various types of bleeds involving internal organs during endoscopic surgeries.

Impact of obesity on short-term outcomes of laparoscopic colorectal surgery for Japanese patients with colorectal cancer: A multicenter study.

INTRODUCTION: The impact of obesity on short-term outcomes after laparoscopic colorectal surgery (LAC) in Asian patients is unclear. The purpose of the present multicenter study was to evaluate the safety and feasibility of LAC in obese Japanese patients. METHODS: We retrospectively reviewed 1705 patients who underwent LAC between April 2016 and February 2019. Patients were classified according to body mass index (BMI): non-obese (BMI < 25 kg/m2 , n = 1335), obese I (BMI 25-29.9 kg/m2 , n = 313), and obese II (BMI ≥30 kg/m2 , n = 57). Clinical characteristics and surgical outcomes were compared among the three groups. RESULTS: The proportion of patients with comorbidities (non-obese, 58.1%; obese I, 69.6%; obese II, 75.4%; P < .001) and median operation time (non-obese, 224 minutes; obese I, 235 minutes; obese II, 258 minutes; P = .004) increased significantly as BMI increased. The conversion rate was similar among the groups (P = .715). Infectious complications were significantly high in obese II patients (non-obese, 10.4%; obese I, 8.3%; obese II, 28.1%; P < .001). Multivariate analysis revealed that in obese II patients, BMI was an independent predictive factor of infectious postoperative complications (odds ratio 2.648; 95% confidence interval, 1.421-4.934; P = .002). CONCLUSION: LAC has an increased risk of postoperative infectious complications in obese II patients, despite improvements in surgical technique. Management of obese II colorectal cancer patients requires meticulous perioperative management.