Yasuhito Iseki

Background: The powered circular stapler, which was developed with the aim of providing reliable and reproducible anastomosis, provides complete anastomosis, resulting in a reduced risk of anastomotic leakage. The aim of this study was to compare the incidence of anastomotic leakage between a conventional manual circular stapler (MCS) and the ECHELON CIRCULAR™ Powered Stapler (ECPS) in patients with left-sided colorectal cancer who underwent anastomosis with the double stapling technique. Methods: A total of 187 patients with left-sided colorectal cancer who underwent anastomosis with the double stapling technique with a conventional MCS or the ECPS during surgery at Osaka City University Hospital between January 2016 and July 2022 were enrolled in this study. Results: The incidence of anastomotic leakage in the ECPS group was significantly lower than that in the MCS group (4.4% versus 14.3%, p = 0.048). Furthermore, even after propensity score matching, an association was found between the use of the ECPS and a reduced incidence of anastomotic leakage. Conclusion: The ECPS has the potential to help reduce the rate of anastomotic leakage in left-sided colorectal surgery.

Background: To prevent anastomotic leakage in patients with left-sided colorectal cancer who underwent double-stapling technique (DST) anastomosis, we investigated a new method: DST anastomosis with a polyglycolic acid (PGA) sheet. This procedure has been shown to have the potential to decrease the rate of anastomotic leakage. However, due to the small number of cases enrolled in our previous study, it was not possible to compare the outcomes of the new and conventional procedures. The aim of this study was to evaluate the effect of the PGA sheet on preventing anastomotic leakage in patients with left-sided colorectal cancer who underwent DST anastomosis by retrospectively comparing the anastomotic leakage rate between the PGA sheet and conventional groups. Methods: A total of 356 patients with left-sided colorectal cancer who underwent DST anastomosis during surgery at Osaka City University Hospital between January 2016 and April 2022 were enrolled in this study. Propensity score matching was performed to reduce the confounding effects secondary to imbalances in the use of PGA sheets. Results: The PGA sheet was used in 43 cases (PGA sheet group) and it was not used in 313 cases (conventional group). After propensity score matching, the incidence of anastomotic leakage in the PGA sheet group was significantly lower than that in the conventional group. Conclusion: DST anastomosis with PGA sheet, which is easy to perform, contributes to the reduction of anastomotic leakage rate by increasing the strength of the anastomotic site.

The preoperative prognostic nutritional index (PNI) has been reported to correlate with the prognosis in patents with various carcinomas. However, the prognostic significance of the postoperative PNI is unknown. The aim of this study was to evaluate the prognostic significance of the postoperative PNI in patients with colorectal cancer (CRC). Two hundred and eighteen patients who underwent potentially curative surgery for stage II/III CRC were enrolled in this study. The PNI was calculated as 10 × serum albumin concentration (g/dl) + 0.005 × lymphocyte count (/mm3). The preoperative PNI was measured within two weeks before the operation and the postoperative PNI were measured at the first visit after leaving the hospital. We then examined the correlations between the preoperative/postoperative PNI and the prognosis for survival. In the validation study, the median preoperative PNI was 47.90 (range: 32.45-61.36) and the median postoperative PNI was 48.69 (range: 32.62-66.96). According to the receiver operating characteristic (ROC) curve, we set 43.0 as the cut-off value in the validation study. For both the preoperative and postoperative PNI, the overall survival rates were significantly worse in the low PNI group in the validation study (preoperative PNI, p = 0.0374; postoperative PNI, p = 0.0005). In the multivariate analysis of the validation study, the combination of pre- and postoperative PNI was an independent predictor of poor overall survival (p = 0.006). The postoperative PNI is, in addition to the preoperative PNI, a useful prognostic marker. The combination of pre- and postoperative PNI was an independent prognostic factor in patients with CRC who underwent potentially curative surgery and is important for considering the long-term outcome in patients with CRC.

Recently, a preoperative systemic inflammatory response has been reported to be a prognostic factor in patients with colorectal cancer (CRC). However, the prognostic significance of a systemic inflammatory response in the early stage after surgery in patients with CRC is unknown. The aim of this retrospective study was to evaluate the prognostic significance of a postoperative systemic inflammatory response in patients with CRC. Two hundred and fifty-four patients who underwent potentially curative surgery for stage II/III CRC were enrolled in this study. Univariate and multivariate analyses were performed to evaluate the relationship between the prognosis and clinicopathological factors, including the neutrophil-to-lymphocyte ratio (NLR) and Glasgow Prognostic Score (GPS), which were measured within two weeks before operation and at the first visit after leaving the hospital. The overall survival rates were significantly worse in the high preoperative NLR/preoperative GPS/postoperative NLR group. A multivariate analysis indicated that only preoperative GPS, postoperative NLR, and the number of lymph node metastases were independent prognostic factors for a poor survival. The postoperative NLR is an independent prognostic factor in patients with CRC who underwent potentially curative surgery.

The pretreatment albumin to globulin ratio (AGR) has been reported to correlate with the long-term survival in patients with various cancers. However, there are no reports regarding the correlation between the pretreatment AGR and chemotherapeutic outcomes in patients with unresectable metastatic colorectal cancer. The aim of this study was to evaluate the prognostic significance of the pretreatment AGR in patients with unresectable metastatic colorectal cancer. A total of 66 patients with unresectable metastatic colorectal cancer who underwent palliative chemotherapy for metastatic tumors were enrolled. The AGR was calculated as follows: Albumin/(Total protein - Albumin). The median pretreatment AGR was 1.254 (range: 0.849-1.840). We set 1.25 as the cut-off value based on the receiver operating characteristic curve. Based on the cut-off value of 1.25, 34 patients were classified into the high-AGR group and 32 patients were classified into the low-AGR group. The high-AGR group had a significantly higher chemotherapeutic disease control rate (p = 0.040) and better progression-free survival (p = 0.0171) and overall survival (p = 0.0360) rates than the low-AGR group. According to a multivariate analysis of survival, the AGR was identified to be an independent prognostic factor for progression-free survival (Hazard Ratio: 2.662, 95% Confidence Interval: 1.085-6.631, p = 0.033) and overall survival (Hazard Ratio: 2.247, 95% Confidence Interval: 1.069-4.722, p = 0.033). The pretreatment AGR is a useful prognostic marker in patients with unresectable metastatic colorectal cancer who receive palliative chemotherapy.