Prognostic Impact and Clinicopathological Features of Multiple Colorectal Cancers and Extracolorectal Malignancies: A Nationwide Retrospective Study.

INTRODUCTION: Multiple primary malignancies (MPMs) are likely to develop in patients with colorectal cancer (CRC); however, their prognoses are unclear. This study aims to investigate the prognostic impacts and clinicopathological features of multiple CRCs and extracolorectal malignancies (EMs) with CRC. METHODS: We retrospectively evaluated a total of 22,628 patients with stage I-III CRC who underwent curative resection at 24 referral institutes in Japan between January 2004 and December 2012. MPMs were classified as synchronous CRCs (SCRCs), metachronous CRCs, synchronous EMs (SEMs), and metachronous EMs. RESULTS: The presence of SCRCs (odds ratio 1.54, p < 0.001) was independently associated with SEMs in the multivariate analyses. SEMs were the strongest poor prognostic factor for OS (hazard ratio [HR] 2.21, p < 0.001) and RFS (HR 1.69, p < 0.001) compared with age, sex, and primary T and N factors. The incidence of stomach cancer was the highest in EMs, followed by lung, breast, and prostate cancers. Multiple CRCs were evenly distributed throughout the right-side colon to the rectum. DISCUSSION/CONCLUSION: SEMs were a strong poor prognostic factor for patients with stage I-III CRC. Patients with CRC, particularly those with SCRCs, should be surveyed for SEMs, especially for stomach and lung cancers.

Liver Injury Among Japanese Patients Treated Using Prophylactic Enoxaparin After Colorectal Surgery.

BACKGROUND: Enoxaparin, a low molecular weight heparin, has been used to prevent thrombotic events during major surgery without increasing the rate of hemorrhage. On the other hand, it was reported to cause liver injury, but the details of liver injury induced by prophylactic enoxaparin after abdominal surgery remain unclear. AIMS: This study aimed to clarify the relationship between prophylactic enoxaparin and liver injury after colorectal surgery, and characterize the injury profile. METHODS: We retrospectively reviewed 732 Japanese patients who underwent elective resection of the colorectum, and compared their clinicopathological background, details of surgery, postoperative complications, including liver injury, and the type of liver injury according to prophylactic use of enoxaparin. Univariate and multivariate analyses were performed to identify risk factors for liver injury during the postoperative period. RESULTS: The rate of liver injury was 8.9% for patients treated by prophylactic enoxaparin and 1.4% for those who did not receive enoxaparin after colorectal surgery (p < 0.0001). The median onset of liver injury among patients receiving enoxaparin was seven days, and the majority demonstrated the hepatocellular pattern. Enoxaparin was one of the independent risk factors for postoperative liver injury by multivariate analysis (odds ratio: 7.63, p < 0.0001). CONCLUSIONS: Prophylactic use of enoxaparin markedly increased the rate of postoperative liver injury in patients who underwent colorectal surgery. Our study confirmed that close monitoring of liver function parameters is essential for patients receiving enoxaparin during the postoperative period.

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.

Less intensive surveillance after radical surgery for stage I-III colorectal cancer by focusing on the doubling time of recurrence.

PURPOSE: To propose a new and improved surveillance schedule for colorectal cancer (CRC) patients by focusing on the recurrence rate, resectability, and especially, the tumor doubling time (DT) of recurrent tumors. METHODS: The subjects of this retrospective review were 1774 consecutive patients who underwent radical surgery for stage I-III CRC between January, 2004 and December, 2015. We calculated the DT by measuring the tumor diameter using computed tomography (CT). RESULTS: The median DT for recurrences in the liver, lung, peritoneum, and other locations were 35, 72, 85, and 36 days, respectively, (p < 0.001) and tumor growth rates differed according to the organs where recurrence developed. Multiple linear regression analysis showed that the DT was strongly associated with the relapse-free interval from primary surgery (p < 0.001), and that the DT in patients with recurrence detected ≥ 3 years after primary surgery was longer by 151.1 days than that in patients with recurrence detected within 1 year after primary surgery. We proposed a less intensive surveillance, which achieved an average cost reduction of 32.5% compared with conventional surveillance in Japan. CONCLUSION: We propose a new and more cost-efficient surveillance schedule for CRC surgery patients in the clinical setting.

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.

Risk factors and therapeutic significance of inguinal lymph node metastasis in advanced lower rectal cancer.

PURPOSE: This study aimed to clarify predictors and therapeutic significance of inguinal lymph node metastasis (ILNM) in patients with rectal cancer. METHODS: Patients with rectal adenocarcinoma invading the anal canal who underwent curative surgery between 2003 and 2019 were retrospectively reviewed. Synchronous and metachronous lymph node (LN) metastasis were collectively defined as final nodal metastasis (f-LNM). Factors associated with f-LNM were analyzed. Moreover, the "modified therapeutic value index," defined by multiplication of the frequency of f-LNM by the 5-year overall survival rate for patients who received treatment for f-LNM, was calculated for each LN area. RESULTS: A total of 145 patients were enrolled (16 patients with f-ILNM). To predict f-ILNM, the cutoff of the inguinal lymph node (ILN) diameter of 8.5 mm gave an area under the curve of 0.889. Dentate line involvement (odds ratio 33.4) and ILN larger than the cutoff of 8 mm (odds ratio 11.9) were independently associated with f-ILNM. The modified therapeutic value indices of the inguinal, lateral pelvic, and mesorectal LNs in the entire population were 6.1, 8.2, and 20.3 points, respectively. In patients with dentate line invasion by cancer, the index of the ILN increased to 11.7 points. In patients with an ILN > 8 mm, the index further increased to 21.1 points. CONCLUSION: Dentate line involvement and ILN > 8 mm predicted the development of ILNM in patients with rectal cancer invading the anal canal. Treatment of the ILN should be considered for patients with the above predictors given the significant therapeutic outcomes.

Efficacy of intraperitoneally administered paclitaxel for colorectal cancer with peritoneal metastases.

PURPOSE: Prognosis after peritoneal metastases in colorectal cancer is worse than that after lung or liver metastases. Previously, we demonstrated the safety of intraperitoneal (ip) administration of paclitaxel (PTX) combined with mFOLFOX6/CapeOX plus bevacizumab for colorectal cancer with peritoneal metastasis in a phase-I trial. Here, we evaluated the efficacy of this chemotherapy. METHODS: We enrolled six patients with histologically confirmed peritoneal metastases secondary to colorectal cancer. PTX was administered through a peritoneal access port, in combination with oxaliplatin-based systematic chemotherapy. Response rate, progression-free survival, 1-year survival rate, frequency of improvement in peritoneal cancer index (PCI), and cytology in peritoneal lavage were evaluated. This study was registered in the University Hospital Medical Information Network Clinical Trial Registry on July 1, 2016 (UNIN000022924). RESULTS: Three patients received the mFOLFOX6-bevacizumab regimen, whereas the other three received the CapeOX-bevacizumab regimen. The response rate was 25%. PCI score improved in 50% of the cases. Peritoneal lavage cytology that was positive in five patients before initiating the chemotherapy turned negative during chemotherapy in all patients. One-year survival rate was 100%, progression-free survival was 8.8 months (range, 6.8-12 months), and median survival time was 29.3 months. CONCLUSION: The ip administration of PTX with systemic chemotherapy can potentially control peritoneal metastases in colorectal cancer.

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.

Loss of RUNX3 Immunoreactivity in Non-Neoplastic Rectal Mucosa May Predict the Occurrence of Ulcerative Colitis-Associated Colorectal Cancer.

BACKGROUND/AIMS: Runt-related transcription factor (RUNX) 3 is a tumor suppressor whose expression is reduced in non-neoplastic rectal mucosa of patients with ulcerative colitis (UC) with coexisting colitis-associated cancer (CAC). We aimed to evaluate RUNX3 utility as a predictive marker for CAC using immunohistochemistry (IHC) for non-neoplastic UC mucosa. METHODS: We retrospectively compared the RUNX3 expression detected by IHC between non-neoplastic rectal biopsy specimens from 20 cases with invasive cancer (CAC group) and 20 cases selected from 138 patients without CAC (non-CAC group) that were treated during the same period (2006-2017) and were matched for sex, duration, extension, and age. We validated the results using tissue microarrays (TMA) of 44 operated cases with CAC. The RUNX3 expression level was determined by calculating the percentage of RUNX3-positive-cells. RESULTS: The RUNX3 expression was lower in the CAC than that in the non-CAC group (35.6 vs. 70.7%, p = 0.03). For a cutoff value of 58%, the sensitivity and specificity for predicting CAC were 75.0 and 70.0% respectively. The immunostaining results for the TMA showed the same trend; 74% of cases with CAC were negative for the RUNX3 expression. CONCLUSION: RUNX3 immunostaining of non-neoplastic mucosa is useful for identifying UC patients at a high risk of developing CAC.

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.

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.

Laparoscopic surgery in rectal cancer patients taking anti-thrombotic therapy.

Background: Several previous studies have shown that laparoscopic resection of rectal cancer is a feasible option. However, its safety and efficacy in patients receiving long-term anti-thrombotic therapy (AT) remain unclear.Material and methods: We retrospectively reviewed 364 patients who underwent elective resection for rectal cancer via a laparoscopic approach between 2007 and 2018 in our institute. Patients were classified according to the long-term use of AT. AT was interrupted perioperatively with or without heparin bridging therapy in all anti-thrombotic users. Clinicopathological factors and surgical outcomes were analyzed between patient groups.Results: Thirty-two patients (9%) receiving AT were older and had lower albumin and hemoglobin levels than those not receiving AT (the non-AT group), and were predominantly male. Estimated blood loss and operative time in the AT group (median: 50 mL and 294 min) did not differ from those in the non-AT group (median: 20 mL and 295 min). There were no intergroup differences in the frequencies of other postoperative complications and oncological outcomes.Conclusions: Our results at the very least can support that laparoscopic surgery for rectal cancer is a safe and feasible option for patients taking long-term AT discontinued perioperatively.

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.

Correlations between the Recurrence Patterns and Sizes of Lateral Pelvic Lymph Nodes before and after Chemoradiotherapy in Patients with Lower Rectal Cancer.

OBJECTIVE: Factors that predict rectal cancer metastasis to the lungs remain undefined. We investigated whether the lateral pelvic lymph node (LPN) sizes before and after chemoradiotherapy (CRT) correlate with lung metastasis after surgery for lower rectal cancer. METHODS: Two hundred and forty patients with lower rectal cancer who received preoperative CRT and curative surgery between 2003 and 2017 were examined. Computed tomography-measured LPN sizes before and after CRT were retrospectively determined by 1 colorectal surgeon who was blinded to the patients' clinical and pathological outcomes. RESULTS: The 5-year cumulative lung metastasis rates were 15.2%. The mean LPN sizes in patients who developed lung metastasis were larger than those in patients who did not (pre-CRT: 8.7 vs. 6.3 mm, p = 0.003; post-CRT: 6.8 vs. 4.5 mm, p = 0.001). The cumulative lung metastasis rate in patients with large LPNs was higher than in those with small LPNs both before and after CRT. On multivariate analysis, lung metastasis was independently correlated with the LPN size only after CRT (hazard ratio [HR]: 5.58), together with the ypT stage (HR: 2.96) and the tumor location (HR: 0.38). CONCLUSIONS: LPN size after CRT is strongly predictive of postoperative lung metastasis in patients with lower rectal cancer.

Pine-cone and villi patterns are endoscopic signs suggestive of ulcerative colitis-associated colorectal cancer and dysplasia.

BACKGROUND AND AIMS: The appropriate site for targeted biopsy during surveillance colonoscopy for ulcerative colitis (UC) is still unclear. We aimed to clarify key endoscopic findings suggestive of neoplastic lesions for targeted biopsy in UC. METHODS: First, we created 769 stereomicroscopic pictures (509 neoplastic, 260 non-neoplastic) mimicking magnifying colonoscopic images from surgically resected specimens, including areas surrounding 25 neoplastic lesions in 15 patients with colitis-associated cancer at a single referral center. Second, we validated the results by using 113 magnifying endoscopic images (64 neoplastic, 49 non-neoplastic) from 39 lesions in 26 patients. Two evaluators, blinded to the pathologic diagnosis, independently classified them according to Kudo's pit pattern and surface morphology, such as pine-cone/villi patterns. The correlation between stereomicroscopic and pathologic findings (neoplastic vs non-neoplastic) for each image was investigated. The interobserver agreement was assessed using kappa statistics. RESULTS: In the stereomicroscopic analysis, neoplastic pit patterns (types III-V) were significantly correlated with the presence of neoplasia (sensitivity 77.4%, specificity 89.5%, kappa value 0.677). Pine-cone/villi patterns also showed high specificity (96.8%) but low sensitivity (21.4%, kappa value 0.625) for neoplasia. Endoscopic validation showed similar trends. A revision of the endoscopic findings of flat dysplasia with non-neoplastic pit patterns revealed that a reddish area may facilitate the identification of such lesions. CONCLUSIONS: Targeted biopsies are recommended, especially for lesions showing pine-cone/villi patterns in addition to neoplastic pit patterns. For flat "non-neoplastic pit patterns," a reddish area may be an indication for a biopsy.

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.

Colon cancer with perforation.

Perforation of the colon is a rare complication for patients with colon cancer and usually requires emergent surgery. The characteristics of perforation differ based on the site of perforation, presenting as either perforation at the cancer site or perforation proximal to the cancer site. Peritonitis due to perforation tends to be more severe in cases of perforation proximal to the cancer site; however, the difference in the outcome between the two types remains unclear. Surgical treatment of colon cancer with perforation has changed over time. Recently, many reports have shown the safety and effectiveness of single-stage operation consisting of resection and primary anastomosis with intraoperative colonic lavage. Under certain conditions, laparoscopic surgery can be feasible and help minimize the invasion. However, emergent surgery for colon cancer with perforation is associated with a high rate of mortality and morbidity. The long-term prognosis seems to have no association with the existence of perforation. Oncologically curative resection may be warranted for perforated colon cancer. In this report, we perform a literature review and investigate the characteristics and surgical strategy for colon cancer with perforation.

Neoadjuvant imatinib therapy in rectal gastrointestinal stromal tumors.

Rectal gastrointestinal stromal tumor (GIST) is a rare entity. Thus, its clinical features have not been well documented, and optimal treatment strategies have not been established. Surgery for rectal GISTs may be difficult because they are often large in size. In addition, rectal GISTs were found to be associated with high rates of local recurrence, regardless of the surgical procedure, before imatinib was introduced in the early 2000s. Since the introduction of imatinib therapy, accumulating evidence suggests that neoadjuvant imatinib therapy may improve the outcomes of rectal GIST treatment. Neoadjuvant imatinib therapy for rectal GISTs offers a number of potential benefits, including tumor downsizing, reduction in mitotic activity, reduced morbidity, and a reduced risk of recurrence. Less radical procedures may allow for the preservation of the anal sphincter and avoidance of a permanent colostomy. This review summarizes the current status and future perspectives of neoadjuvant imatinib therapy for the treatment of rectal GISTs.

Laparoscopic surgery in colon cancer patients treated with chronic anti-thrombotic therapy.

BACKGROUND: Anti-thrombotic medications are commonly used for the treatment and prevention of cardiovascular diseases. Laparoscopic resection of colon cancer has generally been accepted with favorable outcomes being reported in randomized control trials. However, the safety and efficacy of laparoscopic surgery for colon cancer patients receiving chronic anti-thrombotic therapy (AT) remain unclear. METHODS: We identified 951 patients who underwent elective resection for colon cancer between 2009 and 2016 from our database. Patients were classified according to the surgical approach and chronic AT. Clinicopathological factors and surgical outcomes were analyzed between patient groups. Patients' backgrounds were matched using propensity scores in laparoscopic surgery. RESULTS: Anti-thrombotic drugs were chronically used in 135 patients. Among 714 patients who underwent laparoscopy-assisted surgery, 96 received AT. The laparoscopic approach was superior to open surgery in terms of bleeding, surgical site infections, and hospital stay in patients receiving AT. In laparoscopy-assisted surgery, the AT group patients were older and showed lower hemoglobin and albumin levels than those not receiving AT (non-AT group), and were predominantly male. After propensity score matching, estimated blood loss and operative times were similar between the two groups (93 matched patients). The frequencies of postoperative bleeding (2.2%) and thrombotic complications (0%) in the AT group did not significantly differ from those in the non-AT group (1.1 and 0%, respectively). Moreover, AT did not affect survivals. CONCLUSION: Laparoscopic approach appears to be safer and beneficial for colonic cancer patients receiving long-term AT. Bleeding and thrombotic events associated with laparoscopic surgery were not significantly affected by AT.

Elevated risk of stoma outlet obstruction following colorectal surgery in patients undergoing ileal pouch-anal anastomosis: a retrospective cohort study.

PURPOSE: Stoma outlet obstruction (SOO) is a complication following colorectal surgery that requires stoma creation. We aimed to clarify the SOO incidence and identify risk factors for SOO after stoma surgery in patients with ulcerative colitis (UC) or rectal cancer. METHODS: The study included 345 patients with sporadic rectal cancer (n = 301) or UC (n = 44) who underwent stoma surgery between 2012 and 2017. Univariate and multivariate analyses were performed to identify risk factors for SOO. RESULTS: The SOO incidences were 27.3% (n = 12) in patients with UC and 5.6% (n = 17) in patients with sporadic rectal cancer. A multivariate analysis identified UC and loop ileostomy as independent risk factors for SOO. Subanalyses revealed that loop ileostomy was an independent risk factor for patients with UC or sporadic rectal cancer. Most patients who developed SOO were successfully managed with tube drainage through the stoma. However, stoma closure was performed earlier than originally planned in two patients. Among the 29 patients with SOO, 22 (75.9%) developed SOO within 2 weeks postoperatively; the median period between stoma creation and SOO was 6 (range 3-41) days. CONCLUSIONS: UC and loop ileostomy are independent risk factors for postoperative SOO.