Impact of the coronavirus disease 2019 pandemic on gastric and colorectal cancer surgeries: a multicenter epidemiologic study from the Kinki region of Japan.

The coronavirus disease 2019 pandemic affected cancer surgeries and advanced cancer diagnoses; however, the trends in patient characteristics in medical institutions during this time, and the surgical approaches used are unclear. We investigated the impact of the pandemic on gastric and colorectal cancer surgeries in the Kinki region of Japan. We grouped 1688 gastric and 3493 colorectal cancer surgeries into three periods: "pre-pandemic" (April 2019-March 2020), "pandemic 1" (April 2020-March 2021), and "pandemic 2" (April 2021-September 2021), to investigate changes in the number of surgeries, patient characteristics, surgical approaches, and cancer progression after surgery. Gastric and colorectal cancer surgeries decreased from the pre-pandemic levels, by 20% and 4%, respectively, in pandemic 1, and by 31% and 19%, respectively, in pandemic 2. This decrease had not recovered to pre-pandemic levels by September, 2021. Patient characteristics, surgical approaches, and cancer progression of gastric and colorectal surgeries did not change remarkably as a result of the coronavirus disease 2019 pandemic.

Hepatectomy Followed by Adjuvant Chemotherapy with 3-Month Capecitabine Plus Oxaliplatin for Colorectal Cancer Liver Metastases.

LESSONS LEARNED: Three-month adjuvant capecitabine plus oxaliplatin in combination (CAPOX) appeared to reduce recurrence, with mild toxicity in postcurative resection of colorectal cancer liver metastases (CLM). Recurrence in patients who underwent the 3-month adjuvant CAPOX after resection of CLM was most commonly at extrahepatic sites. BACKGROUND: The role of neoadjuvant and adjuvant chemotherapy in the management of initially resectable colorectal cancer liver metastases (CLM) is still unclear. We evaluated the feasibility of 3-month adjuvant treatment with capecitabine plus oxaliplatin in combination (CAPOX) for postcurative resection of CLM. METHODS: Patients received one cycle of capecitabine followed by four cycles of CAPOX as adjuvant chemotherapy after curative resection of CLM. Oral capecitabine was given as 1,000 mg/m2 twice daily for 2 weeks in a 3-week cycle, and CAPOX consisted of oral capecitabine plus oxaliplatin 130 mg/m2 on day 1 in a 3-week cycle. Primary endpoint was the completion rate of adjuvant chemotherapy. Secondary endpoints included recurrence-free survival (RFS), overall survival (OS), dose intensity, and safety. RESULTS: Twenty-eight patients were enrolled. Median age was 69.5 years, 54% of patients had synchronous metastases, and 29% were bilobar. Mean number of lesions resected was two, and mean size of the largest lesion was 31 mm. Among patients, 20 (71.4%; 95% confidence interval, 53.6%-89.3%) completed the protocol treatment and met its primary endpoint. The most common grade 3 or higher toxicity was neutropenia (29%). Five-year recurrence-free survival and overall survival were 65.2% and 87.2%, respectively. CONCLUSION: Three-month adjuvant treatment with CAPOX is tolerable and might be a promising strategy for postcurative resection of CLM.

Observational study of first-line chemotherapy including cetuximab in patients with metastatic colorectal cancer: CORAL trial.

OBJECTIVE: We aimed to clarify the clinical practice and outcomes of first-line cetuximab-containing chemotherapy in patients with metastatic colorectal cancer. Efficacy and safety were evaluated in each group classified by the European Society for Medical Oncology Guidelines 2012. METHODS: This prospective observational study included patients with previously untreated metastatic colorectal cancer from 158 centers in Japan who started first-line cetuximab-containing chemotherapy from January 2012 to June 2013 and were followed for up to 3 years. The resection rates after chemotherapy were calculated and the overall survival was estimated using the Kaplan-Meier method for Group 1 (G1, potentially resectable), Group 2 (G2, not resectable and tumor-related symptoms) and Group 3 (G3, not resectable and asymptomatic). RESULTS: Of 578 patients, 562 were classified into G1 (n = 165), G2 (n = 224) or G3 (n = 173). The resection rate of any site was higher in G1 (57.0%) than in G2 (11.2%) and G3 (11.6%). G1, G2 and G3 showed median overall survivals (95% confidence interval) of 45.9 (38.1-not available), 16.7 (14.5-18.8) and 30.6 (23.2-34.8) months, respectively (P < 0.0001). The common tumor-related symptoms in G2 were pain, fatigue and anorexia, from which 31.7, 22.2 and 14.8% of the patients suffered at baseline. CONCLUSIONS: The expected efficacy and safety of first-line cetuximab-containing chemotherapy were demonstrated in patients with metastatic colorectal cancer under clinical practice in Japan. REGISTERED CLINICAL TRIAL NUMBERS: UMIN000007275.

SMAD4-deficient intestinal tumors recruit CCR1+ myeloid cells that promote invasion.

Inactivation of TGF-beta family signaling is implicated in colorectal tumor progression. Using cis-Apc(+/Delta716) Smad4(+/-) mutant mice (referred to as cis-Apc/Smad4), a model of invasive colorectal cancer in which TGF-beta family signaling is blocked, we show here that a new type of immature myeloid cell (iMC) is recruited from the bone marrow to the tumor invasion front. These CD34(+) iMCs express the matrix metalloproteinases MMP9 and MMP2 and the CC-chemokine receptor 1 (CCR1) and migrate toward the CCR1 ligand CCL9. In adenocarcinomas, expression of CCL9 is increased in the tumor epithelium. By deleting Ccr1 in the background of the cis-Apc/Smad4 mutant, we further show that lack of CCR1 prevents accumulation of CD34(+) iMCs at the invasion front and suppresses tumor invasion. These results indicate that loss of transforming growth factor-beta family signaling in tumor epithelium causes accumulation of iMCs that promote tumor invasion.

Comparison between anatomical subsegmentectomy and nonanatomical partial resection for hepatocellular carcinoma located within a single subsegment: a single-center retrospective analysis.

BACKGROUND/AIMS: For hepatocellular carcinoma (HCC) within a single subsegment, the superiority of anatomical subsegmentectomy over non-anatomical partial resection is still controversial. In this study, we assessed the potential benefit of subsegmentectomy. METHODOLOGY: We selected 44 patients with a single HCC lesion within one subsegment who had undergone anatomical subsegmentectomy or non-anatomical partial resection from among 173 patients who underwent hepatectomy in our hospital from August 2003 to May 2013. We compared the results following anatomical subsegmentectomy (Group A; n = 16) and non-anatomical partial resection (Group N; n = 28). RESULTS: One- and two-year survival rates were 92.5% and 89.3%, respectively; 1- and 2-year recurrence-free survival (RFS) rates were 88.9% and 69.1%, respectively. There was no significant difference in overall survival or RFS between the groups. However, among HBV-positive patients, RFS was significantly better for Group A than Group N (p = 0.008). CONCLUSIONS: For HBV-positive HCC within a single subsegment, we recommend subsegmentectomy.

The preventive surgical site infection bundle in patients with colorectal perforation.

BACKGROUND: Incisional surgical site infection (SSI) is one of the most frequent complications that occur after colorectal surgery. Surgery for colorectal perforation carries an especially high risk of incisional SSI because fecal ascites contaminates the incision intraoperatively, and in patients who underwent stoma creation, the incision is located near the infective origin and is subject to infection postoperatively. Although effectiveness of the preventive SSI bundle of elective colorectal surgery has been reported, no study has focused exclusively on emergency surgery for colorectal perforation. METHODS: Patients with colorectal perforation who underwent emergency surgery and stoma creation from 2010 to 2015 at our center were consecutively enrolled in the study. In March 2013, we developed the preventive incisional SSI bundle for patients with colorectal perforation undergoing stoma creation. The effectiveness of the bundle in these patients was determined and the rates of incisional SSI between before and after March 2013 were compared. RESULTS: We enrolled 108 patients with colorectal perforation who underwent emergency operation during the study period. Thirteen patients were excluded because they died within 30 days after surgery, and 23 patients without stoma were excluded; thus, 72 patients were analyzed. There were 47 patients in the pre-implementation group and 25 patients in the post-implementation group. The rate of incisional SSI was significantly lower after implementation of preventive incisional SSI bundle (43% vs. 20%, p = 0.049). Postoperative hospital stay was significantly shorter after implementation of the bundle (27 vs. 18 days respectively; p = 0.008). CONCLUSIONS: The preventive incisional SSI bundle was effective in preventing incisional SSI in patients with colorectal perforation undergoing emergency surgery with stoma creation.

[A case of locally advanced sigmoid colon cancer treated with neoadjuvant chemoradiotherapy].

The patient was a 38-year-old woman who visited our hospital complaining of nausea and abdominal pain. A colonoscopy revealed an advanced cancer in the sigmoid colon. A computed tomography (CT) scan showed left hydronephrosis and lymph node metastasis to the left iliopsoas muscle and left ureter. No distant metastasis was found. Since the surgical margins were likely to be positive with a one-stage resection, 3 cycles of FOLFOX4 (folinic acid, fluorouracil, and oxaliplatin)were administered after creating a transverse loop colostomy. Although the tumor decreased in size, the surgical margins were still suspected to be positive. For further regional tumor control, radiotherapy (1.8 Gy/day for 25 days) to the medial region of the left iliac bone and oral UFT/LV (uracil and tegafur/Leucovorin)were administered. A partial response(PR)was determined in accordance with the Response Evaluation Criteria in Solid Tumors(RECIST). Sigmoidectomy with partial resection of the left ureter was performed by laparotomy. The histologic response was assessed as Grade 2 and all surgical margins were negative. Preoperative chemoradiotherapy may be an effective therapeutic option for locally advanced colon cancer resistant to conventional preoperative chemotherapy.

[A case of mixed adenoneuroendocrine carcinoma of the transverse colon].

A 7 1-year-old man presented to our hospital with constipation and abdominal pain. Computed tomography of the abdomen and colonoscopy revealed advanced cancer of the transverse colon. The biopsy specimen indicated a highly differentiated adenocarcinoma. The patient underwent extended right hemicolectomy with regional lymph node dissection. Pathological examination showed a neuroendocrine carcinoma (NEC) with concurrent adenocarcinoma of the transverse colon and regional lymph node metastases of the NEC and adenocarcinoma. The histopathological examination confirmed a diagnosis of mixed adenoneuroendocrine carcinoma (MANEC) in accordance with the 2010 WHO Classification of Tumors of the Digestive System. Liver and lung metastases were identified 8 months after the surgery. We administered chemotherapy including 5-fluorouracil, Leucovorin, and oxaliplatin (mFOLFOX) plus bevacizumab, with limited therapeutic effect, as the disease progressed despite treatment. The patient chose best supportive care 13 months after the surgery. Several studies have reported that most patients with adenoendocrine cell carcinoma, including MANEC, experience relapse within 1 year after surgery, and few patients remain disease-free for long periods after surgery. The optimal strategy for the management of MANEC is variable owing to its rarity; only 2 cases of MANEC in the colon, including the present case, have been reported in Japan. It is thus important to gather more evidence on this disease and its management.

[Long-term survival following resection of a leiomyosarcoma originating from the inferior vena cava].

We describe the case of a 46-year-old woman in which a large intra-abdominal tumor was detected using computed tomography. It was a low-density, homogeneous, 7 cm tumor, adjacent to the inferior vena cava (IVC). The tumor, along with a portion of the anterior wall of the IVC, was surgically resected. The tumor originated from the IVC wall, and histopathological examination revealed a diagnosis of leiomyosarcoma. The patient is alive without recurrence 10 years after surgery. Although this disease is rare and typically has a poor prognosis, complete resection with long-term survival is achievable.

Activation of RhoA/ROCK2 signaling by hypoxia-inducible factor 1α in promoting tumor growth and metastasis in human colon cancer.

Background: Recent evidence strongly suggests the profound role of the tumor microenvironment in cancer development and progression. A hypoxic microenvironment is widely acknowledged to be a typical feature of solid tumors, and altered hypoxia-inducible factor 1α (HIF-1α) expression has been associated with the formation and the progression of many solid tumors; however, the underlying mechanism of this relationship remains obscure. Methods: Clinical colorectal cancer tissue samples were collected to detect the differential expression of HIF-1α, Ras homolog family member A (RhoA), and Rho-associated, coiled-coil containing protein kinase 2 (ROCK2). With hypoxic stress, small interfering RNA (siRNA) targeting HIF-1α, lentivirus transfection of RhoA was used to study the mechanism of HIF-1α and RhoA/ROCK2 signaling pathways in the growth and metastasis of colon cancer. Results: According to Cell Counting Kit 8, wound-healing, and Transwell assays, HIF-1α expression activated the RhoA/ROCK2 pathway within colon cancer cell lines, accelerating their growth and expansion. In cells transfected with LV-RhoA, inactivating the RhoA/ROCK2 pathway with the specific inhibitor Y-27632 decreased tumor growth and metastasis under hypoxic conditions, while activating the RhoA/ROCK2 pathway restored these biological properties. The Western blot results showed that the expression levels of pMYPT1, cyclin D1, and MMP2 in the siRNA + LV-RhoA group were also significantly increased compared with those in the siRNA group. Conclusions: For the first time, this study demonstrated that HIF-1α can promote the growth and metastasis of colon cancer via directly affecting RhoA/ROCK2 signaling and thus represents a novel therapeutic target for colon cancer.

Efficacy of surgical staple line reinforcement in Glissonean stapling: A single-center pilot study.

Vascular staplers are routinely used in laparoscopic liver resection, which has become a standard procedure in advanced medical facilities. Although previous reports have outlined the benefits of staple line reinforcement (SLR), its application in Glissonean pedicle transection during hepatic resection remains poorly studied. This study investigated surgical SLR as a tool to enhance staple line strength and improve perioperative hemostasis. Here, 10 patients who underwent laparoscopic liver resection using the Tri-StapleTM2.0 Reinforced Reload were included. Patient characteristics, surgical details, and outcomes were assessed. The results demonstrated successful outcomes with no complications related to bile leakage or injuries during staple insertion. Overall, our findings suggest that SLR can be safely utilized in Glissonean pedicle transection during laparoscopic liver resections. Further studies are required to comprehensively evaluate its benefits compared with conventional surgical staplers.

Inactivation of chemokine (C-C motif) receptor 1 (CCR1) suppresses colon cancer liver metastasis by blocking accumulation of immature myeloid cells in a mouse model.

Recent reports have suggested critical roles of myeloid cells in tumor invasion and metastasis, although these findings have not led to therapeutics. Using a mouse model for liver dissemination, we show that mouse and human colon cancer cells secrete CC-chemokine ligands CCL9 and CCL15, respectively, and recruit CD34(+) Gr-1(-) immature myeloid cells (iMCs). They express CCL9/15 receptor CCR1 and produce matrix metalloproteinases MMP2 and MMP9. Lack of the Ccr1, Mmp2, or Mmp9 gene in the host dramatically suppresses outgrowths of disseminated tumors in the liver. Importantly, CCR1 antagonist BL5923 blocks the iMC accumulation and metastatic colonization and significantly prolongs the survival of tumor-bearing mice. These results suggest that CCR1 antagonists can provide antimetastatic therapies for patients with disseminated colon cancer in the liver.

The Impact of KRAS Status on the Required Surgical Margin Width for Colorectal Liver Metastasis Resection.

Local recurrence after colorectal liver metastasis (CRLM) resection severely affects survival; however, the required surgical margin width remains controversial. This study investigated the impact of KRAS status on surgical margin width and local recurrence rate (LRR) post-CRLM resection. Overall, 146 resected CRLMs with KRAS status (wild-type KRAS (wtKRAS): 98, KRAS mutant (mKRAS): 48) were included. The LRR for each group, R1 (margin positive) and R0 (margin negative), was analyzed by KRAS status. R0 was further stratified into Ra (margin ≥ 5 mm) and Rb (margin < 5 mm). Patients with local recurrence had significantly worse 5-year overall survival than those without local recurrence (p = 0.0036). The mKRAS LRR was significantly higher than wtKRAS LRR (p = 0.0145). R1 resection resulted in significantly higher LRRs than R0 resection for both wtKRAS and mKRAS (p = 0.0068 and p = 0.0204, respectively), and while no significant difference was observed in the Ra and Rb LRR with wtKRAS, the Rb LRR with mKRAS (33.3%) was significantly higher than Ra LRR (5.9%) (p = 0.0289). Thus, R0 resection is sufficient for CRLM with wtKRAS; however, CRLM with mKRAS requires resection with a margin of at least 5 mm to prevent local recurrence.

[A case of lung metastases of carcinoma of the ampulla of vater effectively treated with S-1].

A 70-year-old female patient underwent pylorus-preserving pancreaticoduodenectomy for carcinoma of the ampulla of Vater in March 2007. In April 2009, multiple lung metastases were detected by CT scanning. The patient was treated with S-1 (80mg/day, day 1-28, followed by 2-weeks withdrawal)from April 2009. The shrinkage of lung metastases was diagnosed as a complete response based on the Response Evaluation Criteria in Solid Tumors(RECIST). No severe toxicities were observed. S-1 is an effective and safe anti-cancer agent available for lung metastases of carcinoma of the ampulla of Vater.

Significance of a calcium-binding protein S100A14 expression in colon cancer progression.

Background: The S100 proteins are characterized by two distinct EF-hand calcium-binding motifs. Several members of the S100 family are involved in cancer progression. S100A14, a member of the S100 family, has been cloned and reported in colon-specific microarray databases. In this study, we assessed the biological and functional significance of S100A14 in normal colon and in colon cancer. Methods: The expression of S100A14 in normal colon and colon cancer was assessed. We used in situ hybridization, reverse transcription polymerase chain reaction (RT-PCR), cell migration assay, cell growth assay, western blotting, and immunohistochemical analysis. Clinicopathological examinations were also performed. Results: S100A14 is expressed in normal colon epithelium and several colon cancer cell lines. However, it is not expressed in SW480 cells. S100A14-overexpressing SW480 cells were established by stable transfection. Interestingly, a decrease in cell motility was observed, as determined using two independent migration assays. S100A14-overexpressing SW480 cells showed increased E-cadherin levels but decreased ability to form colonies in soft agar. Moreover, S100A14 expression was decreased in 95 of 154 human colon cancers, and lower S100A14 expression led to worse prognoses. Conclusions: Our results suggest that S100A14 is involved in cell motility, adhesion, and growth changes in colon cancer and that its expression is inversely correlated with colon cancer progression. S100A14 expression in colon cancer is a useful prognostic marker.

Amentoflavone inhibits colorectal cancer epithelial-mesenchymal transition via the miR-16-5p/HMGA2/ß-catenin pathway.

Background: Amentoflavone is a type of bioflavonoid that exists in many Chinese medicines and has anti-inflammatory, antioxidant, antiviral, and anticancer effects. However, the effect of amentoflavone on epithelial to mesenchymal transition (EMT) in human colorectal cancer (CRC) has not been studied. In this study, we aim to explore the effect of amentoflavone on EMT in CRC. Methods: The effects of long noncoding RNA (lncRNA) miR-16-5p on proliferation, migration, and invasion were determined by in vitro and in vivo experiments. A luciferase reporter assay was carried out to reveal the interaction between miR-16-5p and targeted genes. Reverse transcription polymerase chain reaction (RT-PCR) was used to evaluate the expression of miR-16-5p. A western blot assay was used to detect the expression of targeted genes in CRC cells. Results: The results showed that amentoflavone significantly inhibited CRC migration, invasion, and EMT by increasing miR-16-5p expression. Mechanistically, amentoflavone induced inactivation of the Wnt/ß-catenin pathway via miR-16-5p, directly targeting 3'-UTR of HMGA2 to suppress HMGA2 expression in CRC. Clinically, combined miR-16-5p and HMGA2 levels may serve as a predictor for poor prognosis in patients with CRC. Furthermore, an in vivo PDX model suggested that amentoflavone exhibited antitumor effects in vivo via the miR-16-5p/HMGA2/ß-catenin pathway. Conclusions: This is the first study to show that amentoflavone inhibits CRC EMT via the miR-16/HMGA2/ß-catenin pathway. Amentoflavone may be beneficial in treating CRC patients in the clinic.

Indocyanine green plasma clearance rate and 99mTc-galactosyl human serum albumin single-photon emission computed tomography evaluated preoperative remnant liver.

BACKGROUND: Preoperative evaluation of future remnant liver reserves is important for safe hepatectomy. If the remnant is small, preoperative portal vein embolization (PVE) is useful. Liver volume analysis has been the primary method of preoperative evaluation, although functional examination may be more accurate. We have used the functional evaluation liver using the indocyanine green plasma clearance rate (KICG) and 99mTc-galactosyl human serum albumin single-photon emission computed tomography (99mTc-GSA SPECT) for safe hepatectomy. AIM: To analyze the safety of our institution's system for evaluating the remnant liver reserve. METHODS: We retrospectively reviewed the records of 23 patients who underwent preoperative PVE. Two types of remnant liver KICG were defined as follows: Anatomical volume remnant KICG (a-rem-KICG), determined as the remnant liver anatomical volume rate × KICG; and functional volume remnant KICG (f-rem-KICG), determined as the remnant liver functional volume rate based on 99mTc-GSA SPECT × KICG. If either of the remnant liver KICGs were > 0.05, a hepatectomy was performed. Perioperative factors were analyzed. We defined the marginal group as patients with a-rem-KICG of < 0.05 and a f-rem-KICG of > 0.05 and compared the postoperative outcomes between the marginal and not marginal (both a-rem-KICG and f-rem-KICG > 0.05) groups. RESULTS: All 23 patients underwent planned hepatectomies. Right hepatectomy, right trisectionectomy and left trisectionectomy were in 16, 6 and 1 cases, respectively. The mean of blood loss and operative time were 576 mL and 474 min, respectively. The increased amount of f-rem-KICG was significantly larger than that of a-rem-KICG after PVE (0.034 vs 0.012, P = 0.0273). The not marginal and marginal groups had 17 (73.9%) and 6 (26.1%) patients, respectively. The complications of Clavian-Dindo classification grade II or higher and post-hepatectomy liver failure were observed in six (26.1%) and one (grade A, 4.3%) patient, respectively. The 90-d mortality was zero. The marginal group had no significant difference in postoperative outcomes (prothrombin time/international normalised ratio, total bilirubin, complication, post-hepatectomy liver failure, hospital stay, 90-d, and mortality) compared with the not-marginal group. CONCLUSION: Functional evaluation of the remnant liver enabled safe hepatectomy and may extend the indication for hepatectomy after PVE treatment.

Intracorporeal reinforcing sutures reduce anastomotic leakage in double-stapling anastomosis for laparoscopic rectal surgery.

Introduction: In rectal surgery, double-stapled anastomosis is one of the most common techniques. However, the crossing of the staple line is considered a weakness of this method and could lead to anastomotic leakage (AL), which is one of the major complications of rectal cancer surgery. Aim: To investigate the usefulness of laparoscopic intracorporeal reinforcement suturing for preventing AL in laparoscopic rectal surgery. Material and methods: A total of 153 patients with rectal cancer underwent laparoscopic rectal resection with anastomosis using the double-stapling technique between January 2015 and December 2018. Patient characteristics, surgical data, and outcomes were recorded and retrospectively analysed. Patients who received intracorporeal reinforcing sutures (n = 72) were compared with those who did not receive the reinforcing sutures (n = 81). Results: AL was observed in 11 (7.2%) cases overall and in only 1 case in the group with intracorporeal reinforcing sutures. There were no associations between clinicopathological factors and the use of reinforcing sutures. Multivariate analysis revealed that a distance from the anal verge of less than 6.5 cm, diabetes mellitus, and the non-use of reinforcing sutures were independent risk factors for AL. Conclusions: Laparoscopic intracorporeal reinforcing sutures reduced the incidence of AL. Therefore, laparoscopic reinforcing sutures for double-stapled anastomoses seem useful for the prevention of AL.

Pancreatic endometrial cyst: report of a case.

A pancreatic endometrial cyst is an extremely rare disease. Since 1984, only 7 cases have been reported, including the current case. A 35-year-old woman with a history of recurrent severe left upper abdominal pain of 3 months' duration was found to have a cyst in the pancreatic body on the diagnostic imaging findings. With a preoperative diagnosis of mucous cystic adenoma, she underwent a distal pancreatectomy. The histopathological examination of the specimen revealed a pancreatic endometrial cyst. She complained about severe periodic abdominal pain during the convalescence, without any surgical complications. This study reviews previous reports of pancreatic endometrial cysts, and also discusses the clinicopathological features, pathogenesis, and appropriate treatment for this disease.

Laparoscopic Colectomy for Splenic Flexure Cancer Approached from Four Directions.

Background: Standardized protocols for laparoscopic surgery of splenic flexure cancer (SFC) have not been established yet. We described a standardized laparoscopic procedure for SFCs and examined its safety and feasibility. Methods: Laparoscopic colectomy for SFC was performed as follows. The sigmoid colon was mobilized to the descending mesocolon through the medial approach. After confirming the base of the inferior mesenteric artery, the left colic artery was dissected and resected at the base. Further dissection was carried out between the mesentery of the colon and the renal fascia until it exceeded the upper pole of the left kidney and the splenic flexure. The next dissection reached the white line at the lateral side and the sigmoid-descending colon junction. After making an incision at the greater omentum and gastrocolic ligament from the center of the transverse colon to the splenic flexure, the transverse mesocolon base was dissected from the inside splenic flexure for complete mobilization. This was performed by approaching from four directions toward the splenic flexure. Intestinal resection and anastomosis are performed. Results: This procedure was performed in 70 patients with splenic flexure colon cancer (mean age 70 years). The mean operative time was 190 minutes, and the mean blood loss was 2.0 mL. No notable perioperative or postoperative complications were noted. Conclusions: Safe mobilization of the splenic flexure can be achieved by approaching from four directions, and standardization of left colectomy can facilitate complete mesenteric excision.