Impact of metastatic lymph node ratio in node-positive colorectal cancer

Colorectal cancer(CRC) is one of the most common malignant diseases in the world.Presently,the most widely used staging system for CRC is the tumor nodes metastasis classification system,which classifies patients into prognostic groups according to the depth of the primary tumor,presence of regional lymph node(LN) metastases,and evidence of distant metastatic spread.The number of LNs with confirmed metastasis is related to the severity of the disease,but this number depends on the number of LNs retrieved,which varies depending on patient age,tumor grade,surgical extent,and tumor site.Numerous studies and a recent structured review have demonstrated associated improvements in the survival of CRC patients with increasing numbers of LNs retrieved for examination.Hence,the impact of lymph node ratio(LNR),defined as the number of metastatic LNs divided by the number of LNs retrieved,has been investigated in various malignancies,including CRC.In this editorial,we review the literature demonstrating the clinicopathological significance of LNR in CRC pati-ents.Some reports have indicated the advantage of considering the LNR compared to the number of LNs retrieved and/or LN status.When the LNR is taken into consideration for survival analysis,the number of LNs retrieved and/or the LN status is not always found to be a prognostic factor.The cut-off points for LNRs were proposed in numerous studies.However,optimal thresholds for LNRs have not yet received consensus.It is still unclear whether the LNR has more prognostic validity than N stage.For all these reasons,the potential advantages of LNRs in the staging system should be investigated in large prospective data sets.

Single-incision laparoscopic cecectomy for low-grade appendiceal mucinous neoplasm after laparoscopic rectectomy

In this case report,we discuss single-incision laparoscopic cecectomy for low-grade appendiceal neoplasm after laparoscopic anterior resection for rectal cancer.The optimal surgical therapy for low-grade appendiceal neoplasm is controversial;currently,the options include appendectomy,cecectomy,right hemicolectomy,and open or laparoscopic surgery.Due to the risk of pseudomyxoma peritonei,complete resection without rupture is necessary.We have encountered 5 cases of lowgrade appendiceal neoplasm and all 5 patients had no lymph node metastasis.We chose the appendectomy or cecectomy without lymph node dissection if preoperative imaging studies did not suspect malignancy.In the present case,we performed cecectomy without lymph node dissection by single-incision laparoscopic surgery(SILS),which is reported to be a reduced port surgery associated with decreased invasiveness and patient stress compared with conventional laparoscopic surgery.We are confident that SILS is a feasible alternative to traditional surgical procedures for borderline tumors,such as low-grade appendiceal neoplasms.

Efficacy of subcutaneous penrose drains for surgical site infections in colorectal surgery

AIM: To investigate whether a subcutaneous penrose drain would decrease the superficial surgical site infection (s-SSI) rate in elective colorectal surgery. METHODS: This is a comparative study of the historical control type. Intervention consisted of the use of penrose drain in elective open colorectal surgical wounds. The outcome was an incidence of s-SSI. The patients were risk stratified according to the depth of subcutaneous tissue.RESULTS: There were 131 patients (40 patients with high s-SSI risk) in the prior period (from July 2008 to June 2009, when no penrose drains were inserted) and 151 patients (75 patients with high s-SSI risk) in the latter period (from June 2010 to November 2011, when penrose drains were inserted). The overall s-SSI rate was 6.1% and 5.3% during the two periods (P = 0.770), and the s-SSI rate in the high s-SSI risk group was 15.0% and 8.0% (P = 0.242).CONCLUSION: Although penrose drain was not observed to significantly reduce s-SSI, there tended to be a reduced risk of s-SSI in the high s-SSI risk group.

Solitary mediastinal lymph node recurrence after curative resection of colon cancer

We report two cases of solitary mediastinal lymph node recurrence after colon cancer resection. Both cases had para-aortic lymph node metastasis at the time of initial surgery and received adjuvant chemotherapy for 4 years in case 1 and 18 mo in case 2. The time to recurrence was more than 8 years in both cases. After resection of the recurrent tumor, the patient is doing well with no recurrence for 6 years in case 1 and 4 mo in case 2. Patients should be followed up after colon cancer surgery considering the possibility of solitary mediastinal lymph node recurrence if they had para-aortic node metastasis at the time of initial surgery.

Standardized technique for single-incision laparoscopicassisted stoma creation

To describe the procedure, efficacy, and utility of singleincision laparoscopic-assisted stoma creation(SILStoma) for transverse colostomy. Using single-incision laparoscopic surgery, we developed a standardized technique for SILStoma. Twelve consecutive patients underwent SILStoma for transverse colostomy at Osaka Medical Center for Cancer and Cardiovascular Diseases from April 2013 to March 2016. A single, intended stoma site was created with a 2.5-3.5 cm skin incision for primary access to the intra-abdominal space, and it functioned as the main port through which multi-trocars were placed. Clinical and operative factors and postoperative outcomes were evaluated. Patient demographics, including age, gender, body mass index, and surgical indications for intestinal diversion were evaluated. SILStoma was performed in nine cases without the requirement of additional ports. In the remaining three cases, 1-2 additional 5-mm ports were required for mobilization of the transverse colon and safe dissection of abdominal adhesions. No cases required conversion to open surgery. In all cases, SILStoma was completed at the initial stoma site marked preoperatively. No intraoperative or postoperative complications greater than Grade Ⅱ(the Clavien-Dindo classification) were reported in the complication survey. Surgical site infection at stoma sites was observed in four cases; however, surgical interventions were not required and all infectionswere cured completely. In all cases, the resumption of bowel movements was observed between postoperative days 1 and 2. SILStoma for transverse loop colostomy represents a feasible surgical procedure that allows the creation of a stoma at the preoperatively marked site without any additional large skin incisions.