Risk factors for non-reaching of ileal pouch to the anus in laparoscopic restorative proctocolectomy with handsewn anastomosis for ulcerative colitis.

BACKGROUND/AIMS: Restorative proctocolectomy (RPC) with ileal pouch-anal anastomosis and handsewn anastomosis for ulcerative colitis requires pulling down of the ileal pouch into the pelvis, which can be technically challenging. We examined risk factors for the pouch not reaching the anus. METHODS: Clinical records of 62 consecutive patients who were scheduled to undergo RPC with handsewn anastomosis at the University of Tokyo Hospital during 1989-2019 were reviewed. Risk factors for non-reaching were analyzed in patients in whom hand sewing was abandoned for stapled anastomosis because of nonreaching. Risk factors for non-reaching in laparoscopic RPC were separately analyzed. Anatomical indicators obtained from presurgical computed tomography (CT) were also evaluated. RESULTS: Thirty-seven of 62 cases underwent laparoscopic procedures. In 6 cases (9.7%), handsewn anastomosis was changed to stapled anastomosis because of non-reaching. Male sex and a laparoscopic approach were independent risk factors of non-reaching. Distance between the terminal of the superior mesenteric artery (SMA) ileal branch and the anus > 11 cm was a risk factor for non-reaching. CONCLUSIONS: Laparoscopic RPC with handsewn anastomosis may limit extension and induction of the ileal pouch into the anus. Preoperative CT measurement from the terminal SMA to the anus may be useful for predicting non-reaching.

Clinical significance of CD8+ and FoxP3+ tumor-infiltrating lymphocytes and MFG-E8 expression in lower rectal cancer with preoperative chemoradiotherapy.

Preoperative chemoradiotherapy (CRT) for rectal cancer contributes to tumor down-staging and decreases locoregional recurrence. However, each patient shows a significantly different response to CRT. Therefore, the identification of predictive factors to CRT response would be beneficial to avoid unnecessary treatment. Cancer immunity in patients has been suggested to play an important role in the eradication of the tumor by CRT. In the present study, the utility of CD8+ and forkhead box P3 (FoxP3)+ tumor-infiltrating lymphocytes (TILs) and the expression of a novel immuno-regulatory factor, lactadherin (MFG-E8), in predicting CRT effectiveness in patients with rectal cancer was examined. A total of 61 patients with rectal cancer, who underwent curative resection following CRT were included in the study. The numbers of CD8+ and FoxP3+ TILs in a biopsy taken before CRT and MFG-E8 expression level in the specimens obtained at the time of the surgery after CRT were examined using immunohistochemical staining, and their association with clinicopathological characteristics, including patient survival, was determined. The tumors with more CD8+ TILs in the biopsy samples before CRT showed a significantly more favorable CRT response. The patients with tumors and a higher number of CD8+ TILs before CRT also exhibited significantly longer disease-free and overall survival times. Higher MFG-E8 expression level in post-CRT specimens was significantly associated with favorable CRT response; however, no significant association was found with any other clinicopathological characteristics, including survival time. The number of CD8+ TILs before CRT was a valuable predictor for CRT response and was associated with favorable prognosis in patients with lower rectal cancer and who were treated with CRT. High MFG-E8 expression level after CRT was also associated with a favorable CRT response.

Establishment of deformable three-dimensional printed models for laparoscopic right hemicolectomy in transverse colon cancer.

BACKGROUND: Applications of three-dimensional (3-D) printed solid organ models for navigation and simulation were previously reported for abdominal surgeries, and their usefulness was shown by subjective evaluation. However, thus far, no study has examined the effect of intraoperative movements for tissue handling. Novel, deformable 3-D printed models of the superior mesenteric artery (SMA) and superior mesenteric vein (SMV) were created to optimize laparoscopic right hemicolectomy. The aim of this study was to establish a method using these individualized models for use in surgical practice. METHODS: Deformable 3-D models for laparoscopic right hemicolectomy were created using a 3-D printing flexible filamentous material (thermoplastic polyurethane). Five patients with transverse colon cancer who underwent laparoscopic right hemicolectomy with D3 lymphadenectomy between April 2017 and September 2019 were enrolled in this study. Then, the created patient-specific models were compared with the previously recorded intraoperative video views. RESULTS: Transverse colon mobilization changed the spatial arrangement of the branches of the SMA and SMV. The 3-D models reproduced the intraoperative view, although approaches to the dominant vessels to complete D3 lymphadenectomy may vary. CONCLUSIONS: Deformable 3-D models of the SMA and SMV with added branches may aid in optimizing laparoscopic right hemicolectomy operations.

Low preoperative maximum squeezing pressure evaluated by anorectal manometry is a risk factor for non-reversal of diverting stoma.

PURPOSE: A diverting stoma is created to prevent anastomotic leakage and related complications impairing sphincteric function in rectal surgery. However, diverting stoma may be left unclosed. This study is aimed to analyze preoperative factors including anorectal manometric data associated with diverting stoma non-reversal before rectal surgery. We also addressed complications related to diverting stoma in patients undergoing surgery for rectal malignant tumor. METHODS: A total of 203 patients with rectal malignant tumor who underwent sphincter-preserving surgery with diverting stoma were retrospectively evaluated. The risk factors for non-reversal of diverting stoma were identified by univariate and multivariate analyses. For these analyses, anorectal manometric data were measured before rectal surgery. The association between stoma-related complications and other clinicopathological features was also analyzed. RESULTS: During the median follow-up of 46.4 months, 24% (49 patients) did not undergo stoma reversal. Among parameters that were available before rectal surgery, age ≥ 75 years, albumin < 3.5 g/dl, tumor size ≥ 30 mm, tumor distance from the anal verge < 4 cm, and maximum squeezing pressure (MSP) < 130 mmHg measured by anorectal manometry (ARM) were independent factors associated with stoma non-reversal. The most common stoma-related complication was peristomal skin irritation (25%). Ileostomy was the only factor associated with peristomal skin irritation. CONCLUSION: The current study demonstrated that low preoperative MSP evaluated by ARM, old age, hypoalbuminemia, and a large tumor close to the anus were predictive of diverting stoma non-reversal. Stoma site should be well deliberated when patients have the aforementioned risk factors for diverting stoma non-reversal.

Change in skeletal muscle index and its prognostic significance in patients who underwent successful conversion therapy for initially unresectable colorectal cancer: observational study.

BACKGROUND: Systemic therapy can cause loss of skeletal muscle mass in colorectal cancer (CRC) patients in the neoadjuvant and palliative settings. However, it is unknown how the body composition is changed by chemotherapy rendering unresectable CRC to resectable disease or how it affects the prognosis. This study aimed at elucidating the effects of systemic therapy on skeletal muscles and survival in stage IV CRC patients who underwent conversion therapy. METHODS: We reviewed 98 stage IV CRC patients who received systemic therapy in our hospital. According to the treatment setting, patients were divided into the conversion, neoadjuvant chemotherapy (NAC), and palliation groups. The cross-sectional area of skeletal muscles at the third lumbar level and changes in the skeletal muscle index (SMI), defined as the area divided by height squared, during systemic therapy were compared among patient groups. The effects of these parameters on prognosis were analyzed in the conversion group. RESULTS: The mean SMI increased by 9.4% during systemic therapy in the conversion group (n = 38), whereas it decreased by 5.9% in the NAC group (n = 18) and 3.7% in the palliation group (n = 42, p < 0.0001). Moreover, patients with increased SMI during systemic therapy had a better overall survival (OS) than those whose SMI decreased in the conversion group (p = 0.025). The increase in SMI was an independent predictor of favorable OS on multivariate analysis (hazard ratio 0.25). CONCLUSIONS: Stage IV CRC patients who underwent conversion to resection often had an increased SMI. On the other hand, a decrease in the SMI during systemic therapy was a negative prognostic factor in such patients.

Anastomotic bleeding following ileocolic end-to-side anastomosis using a circular stapler: incidence and risk factors.

PURPOSE: To identify the incidence of and risk factors for postoperative bleeding after ileocolic end-to-side anastomosis using a circular stapler. METHODS: We analyzed, retrospectively, the risk factors for postoperative anastomotic bleeding in patients who underwent right-sided colectomy with end-to-side anastomosis done using a circular stapler during colon tumor surgery at our institute between January 2015 and March 2019. RESULTS: Anastomotic bleeding developed in 10 (3.6%) of the total 279 patients. Univariate analysis revealed that age ≥ 80 years (8.8% vs. 1.9%; P = 0.008) and Eastern Cooperative Oncology Group performance status (ECOG PS) ≥ 1 (12.5% vs. 2.8%; P = 0.014) were significant risk factors for anastomotic bleeding. Postoperative anticoagulation therapy was not a risk factor for anastomotic bleeding. Multivariate analysis revealed that only age ≥ 80 years was an independent risk factor (odds ratio 4.12, 95% confidence interval 1.02-16.68, P = 0.047). Six of the ten patients with anastomotic bleeding were treated conservatively, three were treated by colonoscopic clipping, and one required surgery. CONCLUSION: End-to-side anastomosis is safe and feasible, but must be performed carefully in the elderly, who are at higher risk of anastomotic bleeding.

Anal canal adenocarcinoma with pagetoid spread and inguinal lymph node metastasis treated with preoperative chemoradiotherapy: A case report.

Perianal Paget's disease is a rare condition, which is not usually accompanied by cancer. Here, a case of anal canal carcinoma with pagetoid spread and inguinal lymph node metastasis, which exhibited a significant response to preoperative chemoradiotherapy (CRT), is presented. A 58-year-old woman was admitted to The University of Tokyo Hospital with a complaint of discomfort around the anus. Physical examination revealed an erythematous inflamed skin lesion in the perianal region and a tumor of 15 mm in diameter detected on palpation in the left inguinal region, which was diagnosed as metastatic adenocarcinoma by excisional biopsy. Colonoscopy revealed moderately differentiated adenocarcinoma of 15 mm in diameter in the anal canal. Skin biopsy of the perianal region revealed an infiltration of pagetoid cells, which were positive for cytokeratin 7, and negative for cytokeratin 20 and gross cystic disease fluid protein 15. Based on these results, the patient was diagnosed as having anal canal adenocarcinoma with pagetoid spread. The patient received preoperative CRT including the bilateral inguinal region. After CRT, robotic-assisted laparoscopic abdominoperineal resection was performed. The macroscopic findings of the surgical specimen confirmed the formation of a scar as a result of the preoperative CRT. Microscopic examination of the anal tumor revealed no residual carcinoma or lymph node metastasis. In conclusion, this case may suggest the potential applicability of preoperative CRT for the local control of anal canal carcinoma with pagetoid spread.

Upfront Surgery for Small Intestinal Non-Hodgkin's Lymphoma.

BACKGROUND/AIM: The clinical significance of surgery for secondary small intestinal non-Hodgkin's lymphomas (NHL) remains unknown. This study aimed to investigate the efficacy of resection for both primary and secondary small intestinal NHL. PATIENTS AND METHODS: Twenty patients with small intestinal lymphoma who underwent surgical resection at our Institute between 2009 and 2017 were retrospectively evaluated. The clinicopathological and surgery-related factors were reviewed. We also analyzed their surgical outcomes such as postoperative complications, perforation rate, and overall survival (OS). RESULTS: In total, 13 (65%) and 7 (35%) patients had primary and secondary lymphomas, respectively. A total of 70% of patients were diagnosed with aggressive-type lymphomas. A total of 15 (75%) patients had Lugano system stage IV. Only one (5%) patient experienced postoperative grade II deep vein thrombosis and pulmonary embolism. The 3-year OS rate after surgery was 59.6%. CONCLUSION: Surgical resection prior to chemotherapy is a feasible and safe therapeutic strategy for small intestinal NHL.

Metastatic role of mammalian target of rapamycin signaling activation by chemoradiotherapy in advanced rectal cancer.

Postoperative distant metastasis dramatically affects rectal cancer patients who have undergone neoadjuvant chemoradiotherapy (NACRT). Here, we clarified the association between NACRT-mediated mammalian target of rapamycin (mTOR) signaling pathway activation and rectal cancer metastatic potential. We performed immunohistochemistry for phosphorylated mTOR (p-mTOR) and phosphorylated S6 (p-S6) on surgical specimen blocks from 98 rectal cancer patients after NACRT (cohort 1) and 80 colorectal cancer patients without NACRT (cohort 2). In addition, we investigated the association between mTOR pathway activity, affected by irradiation, and the migration ability of colorectal cancer cells in vitro. Based on the results of the clinical study, p-mTOR was significantly overexpressed in cohort 1 (with NACRT) as compared to levels in cohort 2 (without NACRT) (P < .001). High p-mTOR and p-S6 levels correlated with the development of distant metastasis only in cohort 1. Specifically, high p-S6 expression (HR 4.51, P = .002) and high pathological T-stage (HR 3.73, P = .020) after NACRT were independent predictors of the development of distant metastasis. In vitro, p-S6 levels and migration ability increased after irradiation in SW480 cells (TP53 mutation-type) but decreased in LoVo cells (TP53 wild-type), suggesting that irradiation modulates mTOR signaling and migration through cell type-dependent mechanisms. We next assessed the expression level of p53 by immunostaining in cohort 1 and demonstrated that p-S6 was overexpressed in samples with high p53 expression as compared to levels in samples with low p53 expression (P = .008). In conclusion, p-S6 levels after NACRT correlate with postoperative distant metastasis in rectal cancer patients, suggesting that chemoradiotherapy might modulate the mTOR signaling pathway, promoting metastasis.

Assessment of the Changes in Mitochondrial Gene Polymorphism in Ulcerative Colitis and the Etiology of Ulcerative Colitis-associated Colorectal Cancer.

BACKGROUND: Mitochondria are energy-producing organelles, and dysfunction in these organelles causes various types of disease. Although several studies have identified mutations in nuclear DNA that are associated with the etiology of ulcerative colitis (UC), information regarding mitochondrial DNA (mtDNA) in UC is limited. This study aimed to investigate the mitochondrial DNA polymorphism underlying the etiology of UC and UC-associated colorectal cancer. MATERIALS AND METHODS: Next-generation sequencing was performed to assess mitochondrial DNA mutations in 12 patients with UC-associated cancer. The mtDNA mutations in the non-neoplastic mucosa, tumor tissues, and healthy controls were compared. RESULTS: The incidence of mutations of nicotinamide adenine dinucleotide phosphate ubiquinone oxidase subunit, ATP synthetase, and tRNA was higher in non-neoplastic mucosa in those with UC compared with the healthy controls. However, no statistically significant differences were observed in mutations between the tumor tissues and non-neoplastic mucosa in UC. CONCLUSION: Significant mutations in mtDNA were observed in the non-neoplastic mucosa of patients with UC-associated cancer.

Management of isolated para-aortic lymph node recurrence of colorectal cancer.

Isolated para-aortic lymph node recurrence (PALNR) after curative surgery for colorectal cancer (CRC) is rare and its optimal management is not defined clearly. This review investigates the best outcomes among published studies on the management of PALNR in the field of CRC. We searched the PubMed database for studies reporting on the management of isolated PALNR in CRC, published in English or Japanese from January, 2000 to December, 2018. Studies including patients with other metastases were excluded. A total of 24 retrospective studies including 227 patients with PALNR were evaluated. The 3-year overall survival (OS) ranged from 60 to 100%, with a median OS of 34-80 months for patients who underwent PALNR dissection, and 14-42 months for patients who received non-surgical treatment. No surgery-related mortality was reported and the incidence of surgical, mainly low-grade, complications ranged from 33 to 52%. The predictors of improved survival outcome included R0 resection margins. Dissection for PALNR from CRC is considered a feasible treatment option that may yield a better prognosis than non-surgical treatment alone. Preoperative chemotherapy or CRT should be considered for their potential benefits, including a reduction in cancer volume and improved R0 resection rates.

Postoperative chemotherapy is associated with prognosis of stage IV colorectal cancer treated with preoperative chemotherapy/chemoradiotherapy and curative resection.

PURPOSE: Advances in systemic chemotherapy have increased the resectability in colorectal cancer (CRC) associated with metastases even if it was initially unresectable. However, what determines the prognosis of stage IV CRC patients treated by preoperative therapy and surgery remains unclear. We attempted to identify prognostic factors in such CRC patients. METHODS: We reviewed stage IV CRC patients who underwent curative resection between December 2007 and May 2019. The patients who underwent conversion chemotherapy for initially unresectable disease and those who received neoadjuvant chemotherapy (NAC) for resectable synchronous metastases or neoadjuvant chemoradiotherapy (NACRT) for advanced lower rectal cancer with resectable metastases were included. Recurrence-free survival (RFS) and overall survival (OS) were examined by multivariate analyses using Cox proportional hazard models. The RFS and OS curves were analyzed according to postoperative adjuvant chemotherapy (AC). RESULTS: Among 70 patients who underwent curative surgery (34 men, mean age: 60 years old), 33 had initially unresectable disease, 23 received NAC, and 14 NACRT. By multivariate analyses, AC was an independent predictor for improved RFS and OS (hazard ratio = 0.29, p = 0.0002, and hazard ratio = 0.37, p = 0.025). Patients treated with AC showed improved RFS and OS than those without AC (2-year RFS rate = 30% vs 19%, p = 0.031, and 3-year OS rate = 87% vs 67%, p = 0.045). CONCLUSION: Because of its association with improved prognosis, AC should be considered for stage IV CRC patients after curative resection regardless of initial resectability status and preoperative therapy.

Accelerated perineural invasion in colitis-associated cancer: A retrospective cohort study.

Perineural invasion (PNI) is a prognostic factor in patients with colorectal cancer. Neurotrophic factors, molecular determinants of PNI, are altered in their expression levels in patients with ulcerative colitis. In this study, we evaluated the frequency of PNI in colitis-associated cancer (CAC) and sporadic cancer.We retrospectively reviewed 778 colorectal cancers with pathological T3-T4 in 761 patients all of whom were surgically resected without preoperative treatment. The lesions were classified into either CAC or sporadic cancer based on the clinical information. Clinicopathological findings including PNI were compared between CACs and sporadic cancers. Moreover, we analyzed the risk factors for positive PNI by multivariate analysis using a logistic regression model.Ten of the cancers (1.3%) were diagnosed as CACs, and the remaining 768 as sporadic cancers. CACs were characterized by being nonobstructive and predominantly located in the rectum. The CACs had a larger size and more frequent undifferentiated histology than sporadic cancers. PNI was observed more frequently in CACs (90%) than in sporadic cancers without obstruction (45%, P = .007). On multivariate analysis, CAC was one of the significant factors associated with PNI (odds ratio: 9.05, P = .040).Our results suggest that CAC was more likely to exhibit PNI than sporadic colorectal cancer.

Cecal cancer with essential thrombocythemia treated by laparoscopic ileocecal resection: a case report.

BACKGROUND: Essential thrombocythemia (ET) is a myeloproliferative disorder characterized by thrombocytosis and a propensity for both thrombotic and hemorrhagic events. ET rarely occurs simultaneously with colorectal cancer. Here, we report a case of colorectal cancer in an ET patient treated using laparoscopic ileocecal resection. CASE PRESENTATION: A 40-year-old woman was admitted to our hospital after presenting with liver dysfunction. She had been previously diagnosed with ET; aspirin and anagrelide had been prescribed. Subsequent examination at our hospital revealed cecal cancer. Distant metastasis was absent; laparoscopic ileocecal resection was performed. Anagrelide was discontinued only on the surgery day. She was discharged on the seventh postoperative day without thrombosis or hemorrhage. However, when capecitabine and oxaliplatin were administered as adjuvant chemotherapy with continued anagrelide administration, she experienced hepatic dysfunction and thrombocytopenia; thus, anagrelide was discontinued. Five days later, her platelet count recovered. Subsequently, anagrelide and aspirin administration was resumed, without any adjuvant chemotherapy. Her liver function normalized gradually in 4 months. One-year post operation, she is well without tumor recurrence or new metastasis. CONCLUSIONS: To our knowledge, this is the first report of laparoscopic colectomy performed on an ET patient receiving anagrelide. Our report shows that complications such as bleeding or thrombosis can be avoided by anagrelide administration. Contrastingly, thrombocytopenia due to anagrelide intake should be considered when chemotherapy that could cause bone marrow suppression is administered.

The influence of pulmonary comorbidities on treatment choice and short-term surgical outcomes among elderly patients with colorectal cancer.

PURPOSE: Most elderly patients with colorectal cancer have comorbidities and reduced functional reserve, which may increase their risks of postoperative morbidity and mortality, and subsequently influence the treatment choice. Therefore, this study aimed to investigate the treatment choice and compare laparoscopic and open surgery in this setting. METHODS: This retrospective study evaluated 118 patients with colorectal cancer (≥ 85 years old between January 2007 and February 2018) to determine the influence of comorbidities on treatment choice, as well as the safety and feasibility of laparoscopic surgery for these patients. RESULTS: The patients included 42 men (35.6%) and 106 patients (89.8%) with comorbidities. The treatments were curative resection for 90 patients and palliative surgery for 16 patients, including 5 cases of colostomy/ileostomy because of the difficulty of primary cancer resection, pneumonia, or pulmonary hypertension. Twelve patients received non-surgical treatment, including 7 patients with decreased respiratory function because of chronic obstructive pulmonary disease or pneumonia. Forty-three patients underwent open curative resection and 47 patients underwent laparoscopic curative resection, which was associated with a significantly shorter hospital stay (14 days vs. 19days, P < 0.01), a lower morbidity rate (17.0% vs. 37.2%, P = 0.035), and less blood loss (10 mL vs. 140 mL, P < 0.01). One patient in each group died during the postoperative period because of worsened pre-existing pneumonia. CONCLUSION: Laparoscopic surgery was safer and less invasive than open surgery for colorectal cancer among ≥ 85-year-old patients. Pulmonary comorbidities affected the choice of non-curative surgery and may be related to the risk of postoperative mortality.

The component changes of lysophospholipid mediators in colorectal cancer.

Although lysophospholipids are known to play an important role in the development and progression of several kinds of cancers, their role in human colorectal cancer is as yet unclear. In this study, we aim to investigate lysophospholipid levels in colorectal cancer tissues to identify lysophospholipids, the levels of which change specifically in colorectal cancers. We used liquid chromatography-tandem mass spectrometry to measure lysophospholipid levels in cancerous and normal tissues from 11 surgical specimens of sigmoid colon cancers, since recent advances in this field have improved detection sensitivities for lysophospholipids. Our results indicate that, in colon cancer tissues, levels of lysophosphatidylinositol and lysophosphatidylserine were significantly higher ( p = 0.025 and p = 0.01, respectively), whereas levels of lysophosphatidic acid were significantly lower ( p = 0.0019) than in normal tissues. Although levels of lysophosphatidylglycerol were higher in colon cancer tissues than in normal tissues, this difference was not found to be significant ( p = 0.11). Fatty acid analysis further showed that 18:0 lysophosphatidylinositol and 18:0 lysophosphatidylserine were the predominant species of lysophospholipids in colon cancer tissues. These components may be potentially involved in colorectal carcinogenesis.

Molecular Subtypes Are Frequently Discordant Between Lesions in Patients With Synchronous Colorectal Cancer: Molecular Analysis of 59 Patients.

BACKGROUND: We aimed to investigate the molecular features of synchronous colorectal cancer (CRC). MATERIALS AND METHODS: Out of 1,262 patients with CRC, 130 lesions in 59 patients with synchronous CRC were retrospectively analyzed. Microsatellite, v-Ki-Ras2 Kristen rat sarcoma viral oncogene homolog (KRAS), v-raf murine sarcoma viral oncogene homolog B1 (BRAF), tumor protein 53 (TP53) and ß-catenin status were evaluated and compared between synchronous CRC lesions in each patient. RESULTS: The subtypes of instability, BRAF and ß-catenin subtypes was significant but low. Patients with discordant KRAS and TP53 were not concordant between lesions in the same patient, and concordance of microsatellite KRAS/BRAF subtypes comprised 50.8% of those with synchronous CRC. The rate of patients with lesions containing both mutL homolog 1 (MLH1) methylation and microsatellite stable status was 66.7% in those with synchronous CRC, with at least one lesion with high microsatellite instability. CONCLUSION: The present study on synchronous CRC demonstrated a low concordance of molecular subtypes between lesions in the same patient. A molecular analysis of metastatic lesions is warranted for molecular targeted therapy of metastatic synchronous CRC.

Prognostic significance of doubling time in patients undergoing radical surgery for metachronous peritoneal metastases of colorectal cancer.

PURPOSE: The doubling times of tumor volume and tumor markers are associated with the prognosis of liver or lung metastases from colorectal cancer (CRC). However, no studies have assessed peritoneal metastases. Therefore, we aimed to elucidate the association between doubling time and the prognosis of patients who underwent radical surgery for metachronous peritoneal metastases of CRC. METHODS: We calculated the tumor doubling times (TDT) of peritoneal metastases and serum carcinoembryonic antigen-doubling times (CEA-DT) in 33 consecutive patients who underwent radical surgery for metachronous peritoneal metastases between January 2006 and April 2017. The impact of short TDT and CEA-DT on overall survival (OS) and relapse-free survival (RFS) was retrospectively reviewed. RESULTS: In long TDT (> 137 days) group, the 5-year OS rate was 74.1% and median OS time was 6.6 years. In long CEA-DT (> 102 days) group, the 5-year OS rate was 50.0% and median OS time was 5.6 years. Conversely, in short TDT (≤ 137 days) and CEA-DT (≤ 102 days) group, the 5-year OS rates and median OS times were both 0.0% and 3.2 years, respectively. In the multivariate analysis, short TDT was an independent risk factor for poor RFS (P = 0.006) and OS (P = 0.010). Similarly, short CEA-DT was also a poor risk factor for RFS (P < 0.001) and OS (P = 0.012). CONCLUSIONS: Short TDT and CEA-DT are independent risk factors for poor OS and RFS after surgery for metachronous peritoneal metastases of CRC. TDT and CEA-DT should be considered when selecting candidates for surgical resection.

Venous thromboembolism in colorectal surgery: Incidence, risk factors, and prophylaxis.

Colorectal surgery is associated with a high risk of perioperative venous thromboembolism (VTE), and this risk is especially high following colorectal cancer resection and surgery for inflammatory bowel disease. Previous analyses of large databases have reported the incidence of postoperative VTE in this population to be approximately 1.1%-2.5%. Therefore, to minimize this risk, patients should be offered appropriate prophylaxis, which may involve a combination of mechanical and pharmacologic prophylaxis with low-dose unfractionated heparin or low molecular weight heparin as recommended by several guidelines. Prior to initiation of treatment, appropriate risk stratification should be performed according to the patients' basic and disease-related as well as procedure-related risk factors, and post-operative factors. Furthermore, a risk-benefit calculation that takes into account patients' VTE and bleeding risk should be performed prior to starting pharmacologic prophylaxis and to help determine the duration of treatment.