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.

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.

A surgical training system designed to help trainees acquire laparoscopic surgical skills at a rural Japanese institute.

PURPOSE: The Endoscopic Surgical Skill Qualification System was established in Japan to evaluate safe endoscopic surgical techniques and teaching skills. Trainee surgeons obtaining this certification in rural hospitals are disadvantaged by the limited number of surgical opportunities. To address this problem, we established a surgical training system to educate trainee surgeons. METHODS: Eighteen certified expert surgeons affiliated with our department were classified into an experienced training system group (E group, n = 9) and a non-experienced group (NE group, n = 9). Results of the training system were then compared between the groups. RESULTS: The number of years required to become board certified was shorter in the E group (14 years) than that in the NE group (18 years). Likewise, the number of surgical procedures performed before certification was lower in the E group (n = 30) than that in the NE group (n = 50). An expert surgeon was involved in the creation of the certification video of all the E group participants. A questionnaire to board-certified surgeons revealed that guidance by a board-certified surgeon and trainee education (surgical training system) was useful for obtaining certification. CONCLUSIONS: Continuous surgical training, starting with trainee surgeons, appears useful for expediting their acquisition of technical certification in rural areas.

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.

Prognostic factors of para-aortic lymph node metastasis from colorectal cancer in highly selected patients undergoing para-aortic lymph node dissection.

PURPOSE: We investigated the surgical outcomes of para-aortic lymph node (PALN) dissection in patients with colorectal cancer and assessed the prognostic factors related to the survival. METHODS: This single-center retrospective study included 31 patients with synchronous or metachronous PALN metastasis from colorectal cancer who underwent PALN dissection between January 2006 and December 2018. RESULTS: Twenty-one patients had synchronous PALN metastasis, and 10 had metachronous PALN metastasis. Seven patients had either simultaneous distant metastasis or a history of distant metastasis other than PALN metastasis at the time of PALN dissection. Eighteen patients underwent adjuvant chemotherapy. The 5-year overall and recurrence-free survival rates were 54.2 and 17.2%, respectively. A multivariable analysis revealed that rectal cancer, metachronous PALN metastasis, and three or more pathological PALN metastases were significantly poor prognostic factors for the recurrence-free survival. Among patients with rectal cancer, lower rectal cancer and lateral pelvic lymph node metastasis were poor prognostic factors for the overall survival. CONCLUSION: Curative PALN dissection for PALN metastasis from colorectal cancer is feasible with favorable long-term outcomes. A multidisciplinary approach, including surgery and chemotherapy, is needed for colorectal cancer with PALN metastasis to improve the long-term outcomes.

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.

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.

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.

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.

Long-term outcomes and early recurrence after resection for metachronous pulmonary metastases from colorectal cancer.

PURPOSE: Properly selecting patients for aggressive curative resection for pulmonary metastases (PMs) from colorectal cancer (CRC) is desirable. We purposed to clarify prognostic factors and risk factors for early recurrence after metachronous PM resection. METHODS: Clinical data of 151 patients who underwent R0 resection for metachronous PMs from CRC at two institutions between 2008 and 2021 were reviewed. RESULTS: Seventy-six patients (50.3%) were male, and the median age was 71 (42-91) years. The numbers of colon/rectal cancers were 76/75, with pStage I/II/III/IV/unknown in 15/34/86/13/3. The duration from primary surgery to PM was 19.7 (1.0-106.4) months. The follow-up period was 41.9 (0.3-156.2) months. The 1-, 3-, and 5-year recurrence-free survival (RFS) rates were 75.1%, 53.7%, and 51.1%, and the 1-, 3-, and 5-year overall survival (OS) rates were 97.7%, 87.5%, and 68.2%. On multivariate analysis, lymph node metastasis of the primary lesion (HR 1.683, 95%CI 1.003-2.824, p = 0.049) was an independent predictor of poor RFS, and history of resection for extrapulmonary metastasis (e-PM) (HR 2.328, 95%CI 1.139-4.761, p = 0.021) was an independent predictor of poor OS. Patients who experienced early recurrence (< 6 months) after PM resection showed poorer OS than others (3-year OS 50.8% vs. 90.2%, p = 0.002). On multivariate analysis, e-PM was an independent predictor of early recurrence after PM resection (OR 3.989, 95%CI 1.002-15.885, p = 0.049). CONCLUSION: Since a history of e-PM was a predictor of early recurrence and poor OS after R0 resection for PM, surgical treatment of patients with a history of e-PM should be considered carefully.

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.

Efficacy of risk-stratified indicators for adjuvant chemotherapy with fluorouracil and oxaliplatin after hepatectomy for colorectal cancer liver metastasis.

BACKGROUND: The recurrence rate after hepatectomy for colorectal cancer liver metastasis (CRLM) is high, and there is no consensus regarding the effect of adjuvant chemotherapy (AC) using oxaliplatin (doublet AC) in these patients. METHODS: The present study included 91 patients who underwent hepatectomy for complete resection at our hospitals between 2008 and 2018. Based on whether or not they had undergone doublet AC, patients were divided into AC (n = 35) and non-AC (n = 56) groups. The recurrent risk was evaluated by the Memorial Sloan Kettering Cancer Center clinical risk score (MSKCC-CRS). RESULTS: The number of females and median age were higher in the AC group (51.4% vs 25.0%, p = 0.010 and 67 vs 61 years, p = 0.012, respectively). The median follow-up period was 45 months (range, 6-101 months). Doublet AC was an independent prognostic factor for 5-year relapse-free survival (hazard ratio, 0.225; 95%CI, 0.097-0.522; p < 0.001) and for 5-year overall survival (hazard ratio, 0.165; 95%CI, 0.057-0.476; p < 0.001) in multivariate analysis. In patients with a high risk of recurrence (MSKCC-CRS 3-5), 5-year relapse-free survival and 5-year overall survival was higher in the doublet AC group than in the non-AC group (p < 0.01). In low-risk patients (MSKCC-CRS 0-2), 5-year relapse-free survival and 5-year overall survival were similar between the groups. CONCLUSIONS: Doublet AC could have a positive effect on prognosis after curative resection of CRLM, especially in high-risk patients. The selection of patients and AC regimen should take into consideration the risk of recurrence.

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.

Effect of endoscopic surgical skill qualification system for laparoscopic multivisceral resection: Japanese multicenter analysis.

BACKGROUND: The efficacy of laparoscopic multivisceral resection (Lap-MVR) has been reported by several experienced high-volume centers. The Endoscopic Surgical Skill Qualification System (ESSQS) was established in Japan to improve the skill of laparoscopic surgeons and further develop surgical teams. We examined the safety and feasibility of Lap-MVR in general hospitals, and evaluated the effects of the Japanese ESSQS for this approach. METHODS: We retrospectively reviewed 131 patients who underwent MVR between April 2016 and December 2019. Patients were divided into the laparoscopic surgery group (LAC group, n = 98) and the open surgery group (OPEN group, n = 33). The clinicopathological and surgical features were compared between the groups. RESULTS: Compared with the OPEN group, BMI was significantly higher (21.9 vs 19.3 kg/m2, p = 0.012) and blood loss was lower (55 vs 380 ml, p < 0.001) in the LAC group. Operation time, postoperative complications, and postoperative hospital stay were similar between the groups. ESSQS-qualified surgeons tended to select the laparoscopic approach for MVR (p < 0.001). In the LAC group, ESSQS-qualified surgeons had superior results to those without ESSQS qualifications in terms of blood loss (63 vs 137 ml, p = 0.042) and higher R0 resection rate (0% vs 2.0%, p = 0.040), despite having more cases of locally advanced tumor. In addition, there were no conversions to open surgery among ESSQS-qualified surgeons, and three conversions among surgeons without ESSQS qualifications (0% vs 15.0%, p = 0.007). Multivariate analysis revealed blood loss (odds ratio 1.821; 95% CI 1.324-7.654; p = 0.010) as an independent predictor of postoperative complications. Laparoscopic approach was not a predictive factor. CONCLUSIONS: The present multicenter study confirmed the feasibility and safety of Lap-MVR even in general hospitals, and revealed superior results for ESSQS-qualified surgeons.

Short- and mid-term outcomes of laparoscopic colorectal surgery in patients ≥ 85 years old: a multicenter study using a propensity score-matched analysis.

PURPOSE: The number of laparoscopic surgeries for colorectal cancer (CRC) in elderly patients has been increasing. We examined the short- and mid-term outcomes of laparoscopic surgery for CRC in oldest-old patients (≥ 85 years old) compared with the outcomes in younger patients (< 85 years old). METHODS: We retrospectively reviewed primary tumor resection for CRC from April 2015 to December 2020 at six hospitals. Short- and mid-term outcomes were compared after propensity score matching. RESULTS: From the 1374 patients, 126 matched pairs were selected. In the matched cohort, the duration of postoperative hospital stay was longer in the oldest-old patients than in the younger patients (15 days vs. 12 days, p = 0.001). There were no significant differences between the groups in the rate of Clavien-Dindo grade ≥ 2 postoperative complications (21.4% vs. 15.1%, p = 0.254). The oldest-old patients showed a poorer overall survival (OS) than the younger patients (3-year OS, 79.9% vs. 93.5%, p = 0.005) but comparable recurrence-free survival (RFS) (3-year RFS, 72.2% vs. 81.6%, p = 0.530) and cancer-specific survival rates (CSS) (3-year CSS, 90.1% vs. 99.0%, p = 0.124). CONCLUSION: Laparoscopic surgery for CRC in oldest-old patients was performed safely with comparable short-term outcomes to those in younger patients. Although the OS was poorer in the oldest-old patients than in the younger patients, the oncological mid-term outcomes were comparable. Laparoscopic surgery for CRC can be considered acceptable as a treatment in oldest-old patients.

Charlson comorbidity index predicts anastomotic leakage in patients with resected right-sided colon cancer.

PURPOSE: Anastomotic leakage after right-sided colon cancer surgery is a serious complication that affects postoperative mortality. The Charlson comorbidity index (CCI) has been reported to be a useful predictor of postoperative complications. METHODS: A total of 593 cases of right-sided colon cancer resections performed from 2016 to 2020 were examined. The patients were divided into two groups according to the presence or absence of anastomotic leakage (AL, n = 28; no-AL, n = 565); clinicopathological and surgical characteristics were compared between the groups. RESULTS: The AL group patients had a higher comorbidity rate (96.4% vs. 66.9%, p < 0.001), higher CCI score (p < 0.001), higher blood loss (42 mL vs. 23 mL, p = 0.046), and longer hospital stay (30 days vs. 12 days, p < 0.001) than the no-AL group patients. The percentages of chronic pulmonary disease (14.3% vs. 3.9%, p = 0.029), cerebrovascular disease (14.3% vs. 1.9%, p = 0.022), connective tissue disease (39.3% vs. 3.2%, p < 0.001), leukemia (3.6% vs. 0%, p = 0.042), and moderate to severe liver disease (7.1% vs. 0%, p = 0.002) were significantly higher in the AL group. In the multivariate analysis, CCI ≥ 2 was identified as an independent predictor of postoperative anastomotic leakage (hazard ratio 4.91, 95% confidence interval 2.23-10.85, p < 0.001). CONCLUSIONS: CCI could predict anastomotic leakage after right-sided colon cancer surgery.

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.

Improved oncologic outcomes with increase of laparoscopic surgery in modified complete mesocolic excision with D3 lymph node dissection for T3/4a colon cancer: results of 1191 consecutive patients during a 10-year period: a retrospective cohort study.

BACKGROUND: Laparoscopic modified complete mesocolic excision (mCME) with D3 lymph node dissection has been performed with increasing frequency, but the oncological safety remains unclear. This study investigated the oncological safety of laparoscopic modified CME with D3 dissection for pT3/4a M0 colon cancer. PATIENTS: Consecutive patients with pT3/4a M0 colon cancer undergoing curative colectomy at a comprehensive cancer center between 2004 and 2013 were included. Outcomes were compared between early (2004-2008, n = 450) and late (2009-2014, n = 741) periods. Prognostic factors were investigated by multivariate analysis. RESULTS: A total of 1191 patients were eligible. Median follow-up was 57 months. Laparoscopic surgeries were more common in the late period (early vs late: 53.6% vs. 91.8%, p < 0.01). Patients in the late period showed lower blood loss (20 mL vs. 10 mL, p < 0.01), higher number of harvested lymph nodes (18.1 vs. 21.6, p < 0.01) and fewer patients with < 12 harvested nodes (13.6% vs. 5.8%, p < 0.01). Postoperative complication rates were similar between periods (2.7% vs. 2.7%, p = 0.97). Five-year relapse-free survival rate (RFS) (75.3% vs. 82.7%, p < 0.01) and overall survival rate (OS) (86.9% vs. 91.7%, p = 0.01) were higher in the late period. Multivariate analysis revealed laparoscopic surgery as an independent favorable prognostic factor for both RFS (hazard ratio (HR) = 0.73, 95% confidence interval (CI) 0.54-0.99, p = 0.03) and OS (HR = 0.56, 95% CI 0.37-0.83, p < 0.01). CONCLUSION: Improved oncologic outcomes and more frequent laparoscopic surgery during the 10-year period of the study were demonstrated for modified CME with D3 dissection, suggesting the safety of this procedure performed by experienced surgeons for pT3/4a M0 colon cancer.

Comprehensive Comparative Analysis of Prognostic Value of Systemic Inflammatory Biomarkers for Patients with Stage II/III Colon Cancer.

BACKGROUND: Among numerous systemic inflammatory biomarkers, it remains unclear which is the most prognostic for patients with stage II/III colon cancer. We aimed to compare the prognostic significance of systemic inflammatory biomarkers among patients with stage II/III colon cancer. METHODS: We included 1303 patients with stage II/III colon cancer who underwent potentially curative resection from July 2004 to December 2013. Sixteen systemic inflammatory biomarkers-derived from combinations of neutrophils, lymphocytes, monocytes, platelets, C-reactive protein (CRP), and albumin-were compared to identify the biomarker most associated with overall survival (OS) and disease-free survival (DFS) using receiver operating characteristic (ROC) curve analysis. RESULTS: Nine inflammatory biomarkers were predictive for OS, among which lymphocyte-to-CRP ratio (LCR), CRP-to-albumin ratio (CAR), neutrophil × CRP, monocyte × CRP, and platelet × CRP were also predictive for DFS. Among these five inflammatory biomarkers, the area under the curve (AUC) value was highest (0.630) for LCR, being significantly higher than that for neutrophil × CRP (P = 0.010), monocyte × CRP (P = 0.007), or platelet × CRP (P = 0.010) for OS. When the prognostic impact of LCR and CAR were analyzed by multivariate analysis, only LCR was an independent predictor of both OS [hazard ratio (HR), 1.77; 95% confidence interval (CI), 1.23-2.60; P = 0.002] and DFS (HR, 1.29; 95% CI, 1.00-1.66; P = 0.048). CONCLUSIONS: LCR may be the most useful predictive factor for OS and DFS in patients with stage II or III colon cancer.

Factors related to short-term outcomes and delayed systemic treatment following primary tumor resection for asymptomatic stage IV colorectal cancer.

BACKGROUND: The effectiveness of primary tumor resection (PTR) for asymptomatic stage IV colorectal cancer patients to continue prolonged and safe systemic chemotherapy has recently been re-evaluated. However, postoperative complications lead to a prolonged hospital stay and delay systemic treatment, which could result in a poor oncologic outcome. The objective of this study was to identify the risk factors for morbidity and delay of systemic chemotherapy in such patients. METHODS: Between April 2016 and March 2018, 115 consecutive colorectal cancer patients with distant metastasis who had no clinical symptoms and underwent PTR in all participating hospitals were retrospectively reviewed. The patients were divided into two groups according to the presence (CD ≥ 2, n = 23) or absence (CD < 2, n = 92) of postoperative complications. RESULTS: The proportion of combined resection of adjacent organs was significantly higher in the postoperative complication group (p = 0.014). Complications were significantly correlated with longer hospital stay (p < 0.001) and delay of first postoperative treatment (p = 0.005). Univariate and multivariate analyses showed that combined resection (odds ratio 4.593, p = 0.010) was the independent predictor for postoperative complications. Median survival time was 8.5 months. Postoperative complications were not associated with overall survival, but four patients (3.5%) could not receive systemic chemotherapy because of prolonged postoperative complications. CONCLUSIONS: Although PTR for asymptomatic stage IV CRC patients showed an acceptable prognosis, appropriate patient selection is needed to obtain its true benefit.