Endometriosis presenting as a perianal abscess: case report.

Endometriosis is common benign disorder characterized by the presence of endometrial glands and stroma outside the uterine cavity. Endometriosis of perianal region is a rare condition. We report a case of perianal endometriosis presenting initially as a perianal abscess. Transperineal ultrasound showed a 1.5 cm size irregular mixed echogenicity lesion without involving anal sphincters. Complete surgical excision was performed. The histopathological examination confirmed as endometriosis.

N-Terminal Modification of the Tetrapeptide Arg-Leu-Tyr-Glu, a Vascular Endothelial Growth Factor Receptor-2 (VEGFR-2) Antagonist, Improves Antitumor Activity by Increasing its Stability against Serum Peptidases.

The tetrapeptide Arg-Leu-Tyr-Glu (RLYE), a vascular endothelial growth factor (VEGF) receptor-2 antagonist, has been used previously either alone or in combination with chemotherapeutic drugs for treating colorectal cancer in a mouse model. We analyzed the half-life of the peptide and found that because of degradation by aminopeptidases B and N, it had a short half-life of 1.2 hours in the serum. Therefore, to increase the stability and potency of the peptide, we designed the modified peptide, N-terminally acetylated RLYE (Ac-RLYE), which had a strongly stabilized half-life of 8.8 hours in serum compared with the original parent peptide. The IC50 value of Ac-RLYE for VEGF-A-induced endothelial cell migration decreased to approximately 37.1 pM from 89.1 pM for the parent peptide. Using a mouse xenograft tumor model, we demonstrated that Ac-RLYE was more potent than RLYE in inhibiting tumor angiogenesis and growth, improving vascular integrity and normalization through enhanced endothelial cell junctions and pericyte coverage of the tumor vasculature, and impeding the infiltration of macrophages into tumor and their polarization to the M2 phenotype. Furthermore, combined treatment of Ac-RLYE and irinotecan exhibited synergistic effects on M1-like macrophage activation and apoptosis and growth inhibition of tumor cells. These findings provide evidence that the N-terminal acetylation augments the therapeutic effect of RLYE in solid tumors via inhibition of tumor angiogenesis, improvement of tumor vessel integrity and normalization, and enhancement of the livery and efficacy of the coadministered chemotherapeutic drugs. SIGNIFICANCE STATEMENT: The results of this study demonstrate that the N-terminal acetylation of the tetrapeptide RLYE (Ac-RLYE), a novel vascular endothelial growth factor receptor-2 (VEGFR-2) inhibitor, significantly improves its serum stability, antiangiogenic activity, and vascular normalizing potency, resulting in enhanced therapeutic effect on solid tumors. Furthermore, the combined treatment of Ac-RLYE with the chemotherapeutic drug, irinotecan, synergistically enhanced its antitumor efficacy by improving the perfusion and delivery of the drug into the tumors and stimulating the conversion of the tumor-associated macrophages to an immunostimulatory M1-like antitumor phenotype.

Heme oxygenase metabolites improve astrocytic mitochondrial function via a Ca2+-dependent HIF-1α/ERRα circuit.

Heme oxygenase-1 (HO-1) exerts beneficial effects, including angiogenesis and energy metabolism via the hypoxia-inducible factor-1α (HIF-1α) and peroxisome-proliferator-activating receptor-γ coactivator-1α (PGC-1α)/estrogen-related receptor α (ERRα) pathways, respectively, in astrocytes. However, evidence of cross-talk between both pathways in HO metabolite-mediated mitochondrial biogenesis has not been well elucidated. Here, we found that HIF-1α was upregulated in astrocytes after ischemic brain injury following exposure to the carbon monoxide (CO)-releasing compound CORM-2. Experiments with pharmacological inhibitors and target-specific siRNAs revealed that HIF-1α levels were highly correlated with increased PGC-1α and ERRα levels, which were linked to the HO metabolites CO- and bilirubin-induced activation of apical L-type Ca2+ channel and sequential Ca2+-dependent signal transduction. Moreover, HIF-1α was stabilized in a proline hydroxylase-dependent manner by transient induction of intracellular hypoxia via the PGC-1α/ERRα-induced increases in mitochondrial biogenesis and oxygen consumption. HIF-1α knockdown blocked HO-1 system-mediated transcriptional expression of ERRα, but not of PGC-1α, suggesting a possible involvement of HIF-1α in ERRα-mediated mitochondrial biogenesis. These data suggest that the HO-1-derived metabolites, CO and bilirubin, elevate astrocytic mitochondrial function via a HIF-1α/ERRα circuit coupled with L-type Ca2+ channel activation and PGC-1α-mediated oxygen consumption. This circuit may play an important role in repairing neurovascular function after focal ischemic brain injury by stimulating mitochondrial biogenesis.

The prognostic significance of protein arginine methyltransferase 6 expression in colon cancer.

Protein arginine methylation is involved in cellular differentiation and proliferation. Recently, aberrant expression of protein arginine methyltransferases, which are responsible for the methylation reaction, has been reported in various types of cancer. However, there is no clear evidence regarding the prognostic value of abnormal PRMT6 expression in colorectal cancer or the effect of PRMT6 regulation on CRC cells. We investigated the expression patterns of PRMT6 in patients with stage II and III CRC. We detected nuclear expression of PRMT6 in 23.7% of carcinoma samples by immunohistochemistry. Among the clinicopathological parameters, the ratio of poorly differentiated cancer cells was approximately two-fold higher in patients with PRMT6-positive disease than in those with PRMT6-negative disease (p = 0.002). Patients with PRMT6-positive CRC had a shorter disease-free survival than those with PRMT6-negative CRC in both univariate and multivariate analyses (p = 0.018 and p = 0.035, respectively). siRNA-mediated inhibition of PRMT6 expression in CRC cells induced p21WAF1/CIP1 overexpression and suppressed cell growth and colony-forming ability. Concomitantly, apoptosis was induced in PRMT6-suppressed CRC cells. These data suggest that PRMT6 can serve as a biomarker for unfavorable prognosis and as a therapeutic target in CRC.

Clinical Features and Factors Associated With Surgical Treatment in Patients With Complicated Colonic Diverticulitis.

PURPOSE: Colonic diverticulitis is uncommon in Korea, but the incidence is rapidly increasing nowadays. The clinical features and the factors associated with complications of diverticulitis are important for properly treating the disease. METHODS: A retrospective review of the medical records of 225 patients that were prospectively collected between October 2007 and September 2016 was conducted. RESULTS: Diverticulitis was detected mainly in men and women aged 30 to 50 years. Diverticulitis more frequently affected the right colon (n = 194, 86.2%), but age was higher in case of left colonic involvement (42 years vs. 57 years, P < 0.001). Percentages of comorbidities (65.6% vs. 23.8%, P < 0.001), complications (65.6% vs. 6.2%, P < 0.001), and surgical treatment (50.0% vs. 4.1%, P < 0.001) were significantly higher in patients with left colonic diverticulitis. In the multivariate analysis, a risk factor for complicated diverticulitis was left colonic involvement (P < 0.001; relative risk [RR], 47.108; 95% confidence interval [CI], 12.651-175.413). In complicated diverticulitis, age over 50 was the only significant risk factor for surgical treatment (P = 0.024; RR, 19.350; 95% CI, 1.474-254.023). CONCLUSION: In patients over 50 years of age with left colonic diverticulitis, a preventive colectomy should be reconsidered as one of the options for treatment.

Heme oxygenase-1 (HO-1)/carbon monoxide (CO) axis suppresses RANKL-induced osteoclastic differentiation by inhibiting redox-sensitive NF-κB activation.

Heme oxygenase (HO-1) catalyzes heme to carbon monoxide (CO), biliverdin/bilirubin, and iron and is known to prevent the pathogenesis of several human diseases. We assessed the beneficial effect of heme degradation products on osteoclastogenesis induced by receptor activator of NF-κB ligand (RANKL). Treatment of RAW264.7 cells with CORM-2 (a CO donor) and bilirubin, but not with iron, decreased RANKL-induced osteoclastogenesis, with CORM-2 having a more potent anti-osteogenic effect. CORM-2 also inhibited RANKLinduced osteoclastogenesis and osteoclastic resorption activity in marrow-derived macrophages. Treatment with hemin, a HO-1 inducer, strongly inhibited RANKL-induced osteoclastogenesis in wild-type macrophages, but was ineffective in HO-1＋/- cells. CORM-2 reduced RANKL-induced NFATc1 expression by inhibiting IKK-dependent NF-κB activation and reactive oxygen species production. These results suggest that CO potently inhibits RANKL-induced osteoclastogenesis by inhibiting redox-sensitive NF-κB-mediated NFATc1 expression. Our findings indicate that HO-1/CO can act as an antiresorption agent and reduce bone loss by blocking osteoclast differentiation. [BMB Reports 2017; 50(2): 103-108].

Clinical manifestations and risk factors of anastomotic leakage after low anterior resection for rectal cancer.

BACKGROUND: Anastomotic leakage is a common complication that can be associated with catastrophic consequences. However, the risk factors and incidence of anastomotic leakage vary considerably among clinical studies because of the lack of a standardized definition, clinical course and appropriate treatment options. The aim of this study was to identify and classify the clinical manifestations and treatment of anastomotic leakage and analyse the possible risk factors after low anterior resection. METHODS: From January 2009 to June 2010, 632 patients underwent low anterior resection for primary colorectal cancer at Samsung Medical Center. Patients with only one colorectal anastomosis were included from this prospectively collected medical database. RESULTS: The overall leakage rate was 6.0% (n = 38). In cases of generalized leakage, the patients that selected surgical management, regardless of having protective enterostomy and time of occurrence, had better outcomes. Protective enterostomy did not have a preventive effect and was not associated with a lower rate of anastomotic leakage. However, protective enterostomy confined the inflammation to only the pelvic cavity (P = 0.045) and no surgical intervention was initially needed. Male gender (P = 0.021, relative risk (RR) = 2.680, 95% confidence interval (CI) = 1.164-6.171) and side-to-end/J pouch-to-end anastomosis (P = 0.012, RR = 2.696, 95% CI = 1.249-5.818) were significant risk factors that affected anastomotic leakage. CONCLUSION: Surgical management is the best choice for generalized leakage. A protective enterostomy diminished the occurrence of generalized leakage and consequent surgical management; therefore, fragile patients at high risk for anastomotic leakage are recommended to undergo protective enterostomy.

α-Synuclein in the colon and premotor markers of Parkinson disease in neurologically normal subjects.

Extranigral non-motor signs precede the first motor manifestations of Parkinson's disease by many years in some patients. The presence of α-synuclein deposition within colon tissues in patients with Parkinson's disease can aid in identifying early neuropathological changes prior to disease onset. In the present study, we evaluated the roles of non-motor symptoms and signs and imaging biomarkers of nigral neuronal changes and α-synuclein accumulation in the colon. Twelve subjects undergoing colectomy for primary colon cancer were recruited for this study. Immunohistochemical staining for α-synuclein in normal and phosphorylated forms was performed in normally appearing colonic tissue. We evaluated 16 candidate premotor risk factors in this study cohort. Among them, ten subjects showed positive immunostaining with normal- and phosphorylated-α-synuclein. An accumulation of premotor markers in each subject was accompanied with positive normal- and phosphorylated-α-synuclein immunostaining, ranging from 2 to 7 markers per subject, whereas the absence of Lewy bodies in the colon was associated with relative low numbers of premotor signs. A principal component analysis and a cluster analysis of these premotor markers suggest that urinary symptoms were commonly clustered with deposition of peripheral phosphorylated-α-synuclein. Among other premotor marker, color vision abnormalities were related to non-smoking. This mathematical approach confirmed the clustering of premotor markers in preclinical stage of Parkinson's disease. This is the first report showing that α-synuclein in the colon and other premotor markers are related to each other in neurologically normal subjects.

Local recurrence after curative resection for rectal carcinoma: The role of surgical resection.

Local recurrence of rectal cancer is difficult to treat, may cause severe and disabling symptoms, and usually has a fatal outcome. The aim of this study was to document the clinical nature of locally recurrent rectal cancer and to determine the effect of surgical resection on long-term survival.A retrospective review was conducted of the prospectively collected medical records of 2485 patients with primary rectal adenocarcinoma who underwent radical resection between September 1994 and December 2008.In total, 147 (5.9%) patients exhibited local recurrence. The most common type of local recurrence was lateral recurrence, whereas anastomotic recurrence was the most common type in patients without preoperative concurrent chemoradiotherapy (CCRT). Tumor location with respect to the anal verge significantly affected the local recurrence rate (P < 0.001), whereas preoperative CCRT did not affect the local recurrence rate (P = 0.433). Predictive factors for surgical resection of recurrent rectal cancer included less advanced tumor stage (P = 0.017, RR = 3.840, 95% CI = 1.271-11.597), axial recurrence (P < 0.001, RR = 5.772, 95% CI = 2.281-14.609), and isolated local recurrence (P = 0.006, RR = 8.679, 95% CI = 1.846-40.815). Overall survival after diagnosis of local recurrence was negatively influenced by advanced pathologic tumor stage (P = 0.040, RR = 1.867, 95% CI = 1.028-3.389), positive CRM (P = 0.001, RR = 12.939, 95% CI = 2.906-57.604), combined distant metastases (P = 0.001, RR = 2.086, 95% CI = 1.352-3.218), and nonsurgical resection of recurrent tumor (P < 0.001, RR = 4.865, 95% CI = 2.586-9.153).In conclusion, the clinical outcomes of local recurrence after curative resection of rectal cancer are diverse. Surgical resection of locally recurrent rectal cancer should be considered as an initial treatment, especially in patients with less advanced tumors and axial recurrence.

Oncologic Outcomes of Single-incision Laparoscopic Surgery Compared With Conventional Laparoscopy for Colon Cancer.

OBJECTIVE: The aim of this study is to document perioperative results and mid-term oncologic outcomes of single-incision laparoscopic (SIL) colectomy compared to conventional laparoscopic (CL) colectomy. BACKGROUND: SIL surgery is an advance in minimally invasive operative techniques and is widely accepted for various types of surgery. METHODS: We prospectively collected data from 767 patients who underwent radical colectomy (250 SIL colectomy and 517 CL colectomy) between 2010 and 2011 due to primary colon cancer and retrospectively analyzed these patients with propensity score matching. RESULTS: Before matching, patients with CL surgery had a significantly higher percentage of comorbidities (49.2% vs 57.8%, P = 0.024). Tumor location significantly differed between 2 groups: SIL surgery was performed more frequently in patients with right colon cancer. After propensity score matching, each group included 239 patients, and there was no difference between the SIL and CL surgery groups. Estimated blood loss was more in the patients with SIL colectomy, but the rate itself of intraoperative complications was not statistically different (P = 0.662). The median follow-up period was 37 months. There were 20 recurrences in the SIL surgery group (8.4%), including 3 locoregional recurrences and 18 (7.5%) in the CL surgery group. Disease-free survival at 48 months did not differ significantly between the SIL and CL surgery groups (89.8% vs 89.9%, P = 0.548). CONCLUSIONS: SIL colectomy for colon cancer shows probably higher, but an acceptable complication rate and can provide resection and oncologic outcomes equal to those of CL colectomy.

Prognostic significance of perineural invasion in stage IIA colon cancer.

BACKGROUND: Perineural invasion (PNI) may influence the prognosis of colon cancer, but little is known about its predictive value. The aim of this study was to reveal the role of PNI in predicting prognosis after curative resection of colon cancer, especially T3N0. METHODS: Two hundred and fifty-five patients who underwent curative resection for colon cancer at Samsung Medical Center and were later diagnosed with stage T3N0 by a pathological report between November 2004 and December 2007 were retrospectively recruited into the study. RESULTS: Among the 255 patients, 156 were male and 99 were female. The mean age was 61 years (range, 25 to 88 years). The most common tumour location was the sigmoid colon (93 patients, 36.5%). The median follow-up period was 61 months (range, 1 to 98 months). PNI was detected in 18 patients (7.1%). Adjuvant chemotherapy was performed in 205 patients (80.4%). The 5-year disease-free survival rate was greater for patients with PNI negative tumours compared with those with PNI positive tumours (92.0% versus 76.0%, P = 0.025). Adjuvant chemotherapy was not associated with significant differences in survival rate (94.8% versus 96.9%, P = 0.625). On multivariate analysis, PNI was an independent prognostic factor for disease-free and overall survival (P = 0.046, hazard ratio (HR) = 3.113, 95% confidence interval (CI) = 1.020-9.505 and P = 0.019, HR = 9.395, 95% CI = 1.453-60.755 respectively). CONCLUSIONS: PNI is the only significant prognostic factor affecting disease-free and overall survival in patients with T3N0 colon cancer.

Low-Level Microsatellite Instability as a Potential Prognostic Factor in Sporadic Colorectal Cancer.

Although microsatellite instability-high (MSI-H) colorectal cancers (CRCs) have been shown to exhibit a distinct phenotype, the clinical value of MSI-low (MSI-L) in CRC remains unclear. We designed this study to examine the clinicopathologic characteristics and oncologic implications associated with MSI-L CRCs. We retrospectively reviewed data of CRC patients from 3 tertiary referral hospitals in Korea, who underwent surgical resection between January 2003 and December 2009 and had available MSI testing results. MSI testing was performed using the pentaplex Bethesda panel. Clinicopathologic features and oncologic outcomes were compared between MSI-L and microsatellite stable (MSS) CRCs; prognostic factors for survival were also examined. Of the 3019 patients reviewed, 2621 (86.8%) were MSS, and 200 (6.6%) were MSI-L; the remaining 198 (6.6%) were MSI-H. MSI-L and MSS CRCs were comparable in terms of their clinicopathologic features, with the exception of proximal tumor location (MSI-L 30.0% vs MSS 22.1%, P = 0.024) and tumor size (MSI-L 5.2 ±â€Š2.6  cm vs MSS 4.6 ±â€Š2.1  cm, P = 0.001). No differences were detected in either 3-year disease-free survival (MSI-L 87.2% vs MSS 82.6%, P = 0.121) or 5-year overall survival (OS) (MSI-L 74.2% vs MSS 78.3%, P = 0.131) by univariable analysis. However, MSI-L was an independent prognostic factor for poor OS by Cox regression analysis (hazard ratio 1.358, 95% confidence interval 1.014-1.819, P = 0.040). MSI-L may be an independent prognostic factor for OS in sporadic CRCs despite their clinicopathologic similarity to MSS. Further studies investigating the significance of MSI-L in the genesis and prognosis of CRCs are needed.

Perioperative and oncologic outcomes of single-incision laparoscopy compared with conventional laparoscopy for colon cancer: an observational propensity score-matched study.

Single-incision laparoscopic (SIL) surgery is a recent advance in minimally invasive surgical techniques. From May 2011 to August 2012, 77 patients underwent primary SIL surgery for colon cancer by one colorectal surgeon. Among them, 61 patients were one-to-one-matched to control patients who had undergone conventional laparoscopic (CL) surgery with a propensity-matched score, and the outcomes were compared. Two hundred forty-seven patients with colon cancer underwent radical colectomy. Of these, 77 patients underwent SIL colectomy. After matching, there were no significant differences in the general characteristics between the patients undergoing the two types of surgery. Operation time was significantly longer in SIL surgery (139 vs 121 minutes, P = 0.001), but procedure time (107 vs 99 minutes, P = 0.069) was not significantly longer than CL surgery after eliminating closure time (31 vs 22 minutes, P < 0.001) from the operation time. There was no significant difference in postoperative complications between the two groups (3.3 vs 1.6%, P = 1.000). The mean number of harvested lymph nodes was 23 and 22 for SIL and CL surgery, respectively (P = 0.332). The mean follow-up period was 15.7 for the SIL group and 21.4 months for the CL group (P < 0.001) with two recurrences in the SIL group (3.3%) and three recurrences in the CL group (4.9%, P = 1.000). Disease-free survival at 20 months did not differ significantly between the two groups (93.3 vs 94.7%, P = 0.939). SIL for colonic malignancy can be safely applied for various types of operations and can provide equivalent oncologic resection and perioperative outcomes compared with CL surgery.

The role of palliative resection for asymptomatic primary tumor in patients with unresectable stage IV colorectal cancer.

BACKGROUND: The prognostic role of surgical resection of primary tumors is not well established in patients with asymptomatic unresectable stage IV colorectal cancer. OBJECTIVE: The aims of this study were to reveal the prognostic role of surgical resection of primary tumors and to define prognostic factors affecting long-term oncological outcomes in patients with asymptomatic unresectable synchronous metastases. DESIGN: This study was a retrospective analysis of prospectively collected data. PATIENTS: Between 2000 and 2008, a total of 416 patients with asymptomatic unresectable stage IV colorectal cancer were analyzed with propensity score matching. MAIN OUTCOME MEASURES: Prematching baseline characteristics were compared by bivariate analysis, and 113 pairs were selected after 1:1 matching with propensity scores estimated from logistic regression. The primary end point was overall survival. RESULTS: Among 416 patients, 218 (52.4%) underwent palliative resection of the primary tumor. Before propensity score matching, palliative resection resulted in a better survival rate than nonresection in univariate analysis (p < 0.001), but not in multivariate analysis (p = 0.08). After matching, the 5-year overall survival rate was significantly lower for patients with peritoneal metastasis and clinical M1b stage tumors in univariate analysis (p = 0.004 and p = 0.02). However, neither peritoneal metastasis nor clinical M1b stage showed any prognostic significance in multivariate analysis. The overall 5-year survival rate of the postmatching group was 4.9% and 3.5% in the palliative resection and nonresection groups. Consequently, palliative resection was not associated with a significant increase in survival compared with nonresection (p = 0.27). A subgroup analysis performed according to the site of metastasis also did not show any significant survival benefit of palliative resection after matching. LIMITATIONS: Selection bias and potential confounders were limitations of this study. CONCLUSIONS: Resection of the primary tumor in patients with asymptomatic unresectable stage IV colorectal cancer was not associated with an improvement in overall survival after propensity score matching.

Risk factors for the requirement of surgical or endoscopic interventions during chemotherapy in patients with uncomplicated colorectal cancer and unresectable synchronous metastases.

BACKGROUND AND OBJECTIVES: The purpose of this study was to determine the risk factors for requirement of surgical or endoscopic interventions for complications caused by the primary tumor during chemotherapy in patients with unresectable metastatic colorectal cancer. METHODS: A total of 259 patients were diagnosed with uncomplicated colorectal cancer with unresectable metastatic disease and underwent chemotherapy as an initial treatment. Among them, 57 (22.0%) patients underwent palliative interventions because of complications caused by the primary tumor during chemotherapy, including bypass surgery or diverting enterostomy for 22 patients, insertion of colonic stent for 22, and resection of primary tumor for 13. RESULTS: Multivariate analysis revealed that rectal lesion (RR, 2.132; 95% CI, 1.080-4.210; P = 0.029) and tumor size larger than 5 cm (RR = 3.644, 95% CI = 1.923-6.902; P < 0.001) were significant risk factors for requirement of palliative intervention. Patients who had none of the risk factors showed better overall survival than those who had one or more (P = 0.021). CONCLUSIONS: Tumor location in rectum and tumor size larger than 5 cm were significant risk factors for the requirement of surgical or endoscopic interventions during chemotherapy for complications caused by the primary tumor in patients with unresectable metastatic colorectal cancer.

Loss of E-Cadherin expression is associated with a poor prognosis in stage III colorectal cancer.

PURPOSE: The epithelial-mesenchymal transition (EMT) is known to be associated with tumor progression, invasion and metastasis in colorectal cancer (CRC). MATERIALS AND METHODS: Tissue samples obtained from 409 patients with stage III CRC treated from 2006 to 2007 were examined by immunohistochemistry to reveal the expression levels of E-cadherin, fibronectin, vimentin and α-smooth muscle actin (SMA). RESULTS: Among the 409 patients, 402 cases (98.3%) showed positive E-cadherin expression. Positive E-cadherin expression was associated with well or moderately differentiated cell types and a stable microsatellite status. In multivariate analysis, a preoperative carcinoembryonic antigen level >5 ng/ml (p = 0.021), advanced N stage (p = 0.017), positive vascular invasion (p = 0.048), positive perineural invasion (p = 0.002) and negative E-cadherin expression (p = 0.002, relative risk = 5.098, 95% CI = 1.801-14.430) were poor prognostic factors affecting disease-free survival. The declining E-cadherin expression was associated with a poor outcome in terms of overall survival in univariate (p = 0.016) but not in multivariate analyses (p = 0.303, relative risk = 1.984, 95% CI = 0.539-7.296). Fibronectin, vimentin and α-SMA were of no prognostic value in this study. CONCLUSION: The expression pattern of EMT markers in stage III CRC suggests that declining E-cadherin expression is a possible immunohistochemical predictor of patient prognosis.

Single-incision laparoscopic right colectomy compared with conventional laparoscopy for malignancy: assessment of perioperative and short-term oncologic outcomes.

BACKGROUND: Laparoscopic colectomy for malignancy currently is the standard operative technique together with open colectomy. Single-incision laparoscopic surgery (SIL) is a recent advance in minimally invasive surgical techniques. This study aimed to compare SIL right colectomy with conventional laparoscopy (CL) used to treat patients with colon cancer. METHODS: This study was a retrospective analysis of data from the authors' prospectively collected colorectal surgery database. Between August 2009 and November 2010, 159 patients who underwent primary laparoscopic right colectomy at the Samsung Medical Center were recruited to participate in this study. Of these, 66 patients underwent SIL colectomy. RESULTS: The SIL and CL right colectomy groups did not differ significantly in terms of general characteristics including age, sex, body mass index (BMI), American society of anesthesiology (ASA) score, previous abdominal operation, and diagnosis. The two groups also did not differ significantly in terms of perioperative complications (9.1 vs. 15.1 %, p = 0.335). Oncologic resection was similar in the two groups. The mean number of harvested lymph nodes was 24 for SIL and 27 for CL right colectomy (p = 0.068). Tumor size, disease stage, adjuvant chemotherapy, and proximal and distal resection margins did not differ significantly between the two groups. The mean follow-up period was 24.5 for the SIL group and 26.4 months for the CL group (p = 0.098), with six recurrences in the SIL group (9.1 %) and three recurrences in the CL group (3.2 %) (p = 0.120). One death occurred in the CL group. Disease-free survival at 24 months did not differ significantly between the two groups (89.7 vs. 96.3 %, p = 0.120). CONCLUSION: The findings show that SIL right colectomy for colon cancer is safe and can provide resection and oncologic outcomes equal to those of conventional laparoscopic right colectomy.

Oncologic outcome after cessation or dose reduction of capecitabine in patients with colon cancer.

PURPOSE: Oral capecitabine has been used as adjuvant therapy for colorectal cancer patients since the 1990s. Patient-initiated cessation or reduced use of capecitabine occurs widely for various reasons, yet the consequences of these actions are unclear. The present study sought to clarify treatment outcomes in such patients. METHODS: The study included 173 patients who had been diagnosed with stage II or III colon cancer according to the pathologic report after radical surgery at Samsung Medical Center from May 2005 to June 2007 and who had received capecitabine as adjuvant therapy. The patients were divided into groups according to whether the dose was reduced (I, dose maintenance; II, dose reduction) or stopped (A, cycle completion; B, cycle cessation). Recurrence and disease-free survival rates between the two groups each were analyzed. RESULTS: Of the 173 patients, 128 (74.6%) experienced complications, most frequently hand-foot syndrome (n = 114). Reduction (n = 35) or cessation (n = 18) of medication was most commonly due to complications. Concerning reduced dosage, both groups displayed no statistically significant differences in recurrence rate and 3-year disease-free survival rate. Concerning discontinued medication use, the cycle completion group showed an improved recurrence rate (P = 0.048) and 3-year disease-free survival rate (P = 0.028). CONCLUSION: The results demonstrate that maintaining compliance with capecitabine as an adjuvant treatment for colon cancer to preventing complications positively affects patient prognosis.