Oncologic outcomes of preoperative stent insertion first versus immediate surgery for obstructing left-sided colorectal cancer.

BACKGROUND: Colonic self-expanding metallic stenting (SEMS) is widely used for the treatment of malignant colonic obstruction as a bridge to elective surgery. However, the effects of colonic stenting on long-term oncologic outcomes are debatable. This study aimed to compare the long-term oncologic outcomes of preoperative SEMS insertion with those of immediate surgery in patients with obstructing left-sided colorectal cancer. METHODS: A cohort of consecutive patients who underwent radical surgery for obstructing left-sided colorectal cancer between 2004 and 2011 in five tertiary referral hospitals were analyzed. Long-term survivals were analyzed and adjusted using the inverse probability of treatment weighting method, based on propensity scores, to reduce selection bias. RESULTS: One hundred and nine patients underwent immediate surgery, and 226 underwent stent insertion before surgery. Disease-free survival did not differ significantly in both the unadjusted population (hazard ratio [HR] 1.063, 95% confidence interval [CI] 0.730-1.548; Log-rank, p = 0.746) and the adjusted population (HR 0.122, 95% CI 0.920-1.987; Log-rank, p = 0.122). Overall survival also did not differ significantly in both the unadjusted population (HR 0.871, 95% CI 0.568-1.334; Log-rank, p = 0.526) and the adjusted population (HR 1.023, 95% CI 0.665-1.572; Log-rank, p = 0.916). Defunctioning stoma formation was less in the SEMS insertion group than immediate surgery group (adjusted, 14.6% vs. 41.3%, p < 0.001). CONCLUSION: The 'bridge to surgery' strategy using metallic stents was oncologically comparable to immediate surgery in patients with malignant left-sided colorectal obstruction.

Long-term outcomes after Natural Orifice Specimen Extraction versus conventional laparoscopy-assisted surgery for rectal cancer: a matched case-control study.

PURPOSE: The aim of this study was to compare the long-term outcomes of total laparoscopic surgery with Natural Orifice Specimen Extraction (NOSE) with those for conventional laparoscopy (CL)-assisted surgery for treating rectal cancers. METHODS: We reviewed the prospectively collected records of 844 patients (163 NOSE and 681 CL) who underwent curative surgery for mid- or upper rectal cancers from January 2006 to November 2012. We applied propensity score analyses and compared oncological outcomes for the NOSE and CL groups in a 1:1 matched cohort. RESULTS: After propensity score matching, each group included 138 patients; the NOSE and CL groups did not differ significantly in terms of baseline clinical characteristics. The median follow-up was 57.7 months (interquartile range, 42.4-82.5 months). The combined 5-year local recurrence rate for all tumor stages was 4.1% (95% confidence interval [CI], 0.9%-7.4%) in the NOSE group and 3.0% (95% CI, 0%-6.3%) in the CL group (P = 0.355). The combined 5-year disease-free survival rates for all stages were 89.3% (95% CI, 84.3%-94.3%) in the NOSE group and 87.3% (95% CI, 81.8%-92.9%) in the CL group (P = 0.639). The postoperative mean fecal incontinence scores at 6, 12, and 24 months were similar between the 2 groups. CONCLUSION: In our experience, NOSE for mid- and upper rectal cancer had acceptable long-term oncologic outcomes comparable to those of conventional minimal invasive surgery and seems to be a safe alternative to reduce access trauma.

Endoscopic submucosal dissection for nonpedunculated submucosal invasive colorectal cancer: is it feasible?

BACKGROUND/AIMS: There have been no definite indications for additional surgical resection after endoscopic submucosal dissection (ESD) of submucosal invasive colorectal cancer (SICC). The aims of this study were to evaluate the feasibility of ESD for nonpedunculated SICC and to determine the need for subsequent surgery after ESD. PATIENTS AND METHODS: A total of 150 patients with nonpedunculated SICC in resected specimens after ESD were analyzed. Among them, 75 patients underwent subsequent surgery after ESD. Clinical outcomes of ESD and histopathological risk factors for lymph node (LN) metastasis were evaluated. RESULTS: The en-bloc resection and complete resection (R0) rates of ESD were 98% (147/150) and 95.3% (143/150), respectively. None of the patients had delayed bleeding after ESD. Perforations occurred in seven patients (4.7%), which were successfully treated by endoscopic clipping. After subsequent surgery for 75 patients, LN metastases were found in 10 cases (13.3%). The incidence of LN metastasis was significantly higher in tumors featuring submucosal invasion of at least 1500 µm, lymphovascular invasion, and tumor budding. Multivariate analysis showed that lymphovascular invasion (P=0.034) and tumor budding (P=0.015) were significantly associated with LN metastasis. Among the 150 patients, no local recurrence or distant metastasis was detected, except one patient with risk factors and who refused subsequent surgery, during the overall median follow-up of 34 months (range, 5-63 months). CONCLUSION: ESD is feasible and may be considered as an alternative treatment option for carefully selected cases of nonpedunculated SICC, provided that the appropriate histopathological curative criteria are fulfilled in completely resectable ESD specimens.

Rectal neuroendocrine and L-cell tumors: diagnostic dilemma and therapeutic strategy.

Rectal neuroendocrine tumors (NETs) are currently divided into L-cell and non-L-cell types. In the World Health Organization 2010 classification, L-cell tumors are defined as borderline, whereas non-L-cell tumors are considered to represent malignancies. To establish differential diagnostic criteria and therapeutic strategy, we investigated the pathologic features of rectal NETs associated with lymph node metastasis and the clinicopathologic significance of the L-cell phenotype. We analyzed 284 patients with rectal NETs. Factors, including T stage, mitosis, histologic pattern, lymphatic invasion, tumor border, and lymph node metastasis, were retrospectively evaluated. We also evaluated tumor immunoreactivity for L-cell markers, including glucagon-like peptide 1, pancreatic peptide, and peptide YY, in 240 cases. L-cell immunoreactivity was detected in 189 of 240 NETs (79%). Of the factors evaluated, only age and the frequency of lymphatic invasion were significantly different between patients with L-cell and non-L-cell tumors. Of the 284 patients, 18 (6.3%) had lymph node metastases. Lymphatic invasion and T stage were independent risk factors for lymph node metastasis. Subgroup analysis based on tumor size showed lymph node metastasis in 0%, 4%, 24%, and 100% of patients with NETs with a size of <5, 5 to 9, 10 to 14, and ≥ 15 mm, respectively. Depth of tumor invasion, lymphatic invasion, and mitosis were correlated with tumor size (P<0.0001). In conclusion, L-cell phenotype alone does not guarantee favorable biological characteristics. The clinical management of rectal NETs should depend on tumor size. Careful pathologic examination of lymphatic invasion is necessary.

Regression of giant pseudopolyps in inflammatory bowel disease.

Inflammatory pseudopolyps are formed in the regenerative and healing phases of ulcerated epithelium. Giant pseudopolyposis of the colon (pseudopolyp larger than 1.5 cm in size) is a very rare complication of inflammatory bowel disease and it may lead to colonic intussusception or luminal obstruction, but the more important clinical significance is that it can be endoscopically confused with a malignancy, although it is generally regarded as having no malignant potential. It has been reported that giant pseudopolyposis of the colon rarely regresses with medical management alone and this sometimes require surgical or endoscopic resection. This report illustrates 2 unusual cases of giant pseudopolyps associated with Crohn's disease and ulcerative colitis, and these giant pseudopolyps were initially confused with villous adenoma or adenocarcinoma, but they showed regression after adequate medical therapy.

A case of Crohn's disease with improvement after azathioprine-induced pancytopenia.

The immunosuppressant azathioprine (AZA) is widely used in the treatment of inflammatory bowel disease (IBD) for both inducing and maintaining remission. However, the adverse effects of AZA can often necessitate a dose reduction or discontinuation. Bone marrow suppression is one of the most serious complications with AZA treatment. On the other hand, some reports have suggested that neutropenia during AZA therapy reduced the relapse rates of IBD patients, and there have been some cases where eradication of the sensitized leukocytes by leukapheresis or bone marrow transplantation improved the IBD, which may explain the relevant role of neutropenia in controlling disease activity. This report describes the case of a 22-year-old male patient who had Crohn's colitis and complicated perianal fistulas that required immunosuppression; he achieved endoscopically determined remission and showed accelerated mucosal healing as well as clinical remission following the AZA-induced pancytopenia.

Magnesium citrate with a single dose of sodium phosphate for colonoscopy bowel preparation.

AIM: To evaluate the efficacy and acceptability of magnesium citrate and a single dose of oral sodium phosphate (45 mL) solution for morning colonoscopy bowel preparation. METHODS: A total of 159 patients were randomly assigned to receive two split doses of 90 mg of sodium phosphate (Group I, n = 79) or magnesium citrate (250 mL, the day before the procedure) followed by 45 mL of sodium phosphate (the day of procedure, Group II, n = 80). The quality of bowel cleansing and the acceptability of each regimen were compared, including the satisfaction, taste, willing to repeat and adverse effects of each regimen. RESULTS: The quality of bowel cleansing of Group II was as good as that of Group I (An Aronchick scale score of good or excellent: 70.9% vs 81.0%, respectively, P = 0.34; the Ottawa system score: 4.4 ± 2.6 vs 3.8 ± 3.0, respectively, P = 0.76). There was no statistically significant difference between both groups with regard to acceptability, including the satisfaction, taste and willingness to repeat the regimen. A significantly greater number of older patients (over 65 years old) in Group II graded the overall satisfaction as satisfactory (48.1% vs 78.1%, respectively; Group I vs Group II, P = 0.01). There were no significant adverse reactions. CONCLUSION: Magnesium citrate and a single dose of sodium phosphate was as effective and tolerable as the conventional sodium phosphate regimen and is a satisfactory option.

Colonoscopy screening for individuals aged 40-49 years with a family history of stomach cancer in Korea.

BACKGROUND: For asymptomatic individuals aged 40-49 years, screening for colorectal cancer is recommended only if individuals are at an increased risk. A family history of colon cancer (FHCRC) is considered to increase risk, however, whether family history of stomach cancer (FHSC) increases the risk of adenoma is not well known. We aimed to see whether FHSC increases the risk in asymptomatic individuals aged 40-49 years in Korea. METHODS: Among asymptomatic individual aged 40-49 years who underwent colonoscopy screening, risk of adenoma was assessed according to FHCRC or FHSC. RESULTS: Of 3,160 individuals, male comprised 1,602 individuals (50.7%). FHCRC and FHSC was noticed in 163 (5.2%) and 227 (7.0%) individuals, respectively. Prevalence of adenoma was 31.9 %, 28.8%, and 22.3% for individuals with FHCRC, individuals with FHSC, and individuals without family history of cancer, respectively. FHSC was an independent risk factor for adenoma (odds ratio, 1.38; 95% confidence interval, 1.02-1.87, P = 0.039) in asymptomatic individuals aged 40-49 years. Compared with individuals with FHCRC, individuals with FHSC showed no difference in risk for adenoma (P = 0.347). CONCLUSIONS: As with individuals with FHCRC, individuals with FHSC might need to be considered as an individual with increased risk for adenoma. Therefore, earlier screening might be needed for asymptomatic individuals aged 40-49 years with FHSC in Korea.

Comparison of one-stage managements of obstructing left-sided colon and rectal cancer: stent-laparoscopic approach vs. intraoperative colonic lavage.

PURPOSE: We evaluated the operative outcomes of laparoscopic surgery following self-expandable metallic stent compared to one-stage emergency surgical treatment. METHODS: From April 1996 to October 2007, 95 consecutive patients with left-sided malignant colorectal obstruction were enrolled. Twenty-five patients were assigned to the preoperative stenting and elective laparoscopic surgical treatment group (SLAP) and 70 to the emergency open surgery with intraoperative colon lavage group (OLAV). RESULTS: Among the 25 patients in the SLAP group, a primary anastomosis was possible in all patients and a diverting stoma was needed in one patient. The operative time was shorter in the SLAP group (198.53 vs. 262.17 min, P = 0.002). Tumor size, number of retrieved lymph nodes, and pathological stage were similar in both groups. The rate of anastomotic failure was similar and postoperative complications occurred less in the SLAP group (5.9% vs. 31.4%, P = 0.034). The passage of flatus and oral intake were resumed earlier in the SLAP group (2.88 vs. 3.68 days, P = 0.046 and 5.18 vs. 6.65 days, P < 0.001, respectively). The postoperative hospital stay was shorter in the SLAP group (10 vs. 15.4 days, P = 0.013). CONCLUSIONS: In patients with left-sided malignant colon and rectal obstruction, laparoscopic surgery after SEMS could be safely performed with successful early postoperative outcomes.

Association of vascular endothelial growth factor gene polymorphisms with susceptibility and clinicopathologic characteristics of colorectal cancer.

Since vascular endothelial growth factor (VEGF) is known to be a potent pro-angiogenic factor, we evaluated the potential association of two VEGF gene polymorphisms (-634G>C and 936C>T) with the susceptibility and the clinicopathologic characteristics of colorectal cancer (CRC). The VEGF genotypes were determined using fresh colorectal tissue from 465 patients who had undergone a surgical resection and peripheral blood lymphocytes from 413 healthy controls by PCR/DHPLC assay. For the -634G>C polymorphism, the -634 GC or CC genotype was associated with a decreased risk of CRC (odds ratio [OR], 0.62; p=0.001) as a dominant model of C allele, whereas the 936 TT genotype correlated with advanced stage/ metastasis, a high serum level of CA19-9, and an higher grade in patients with CRC. In the haplotype analyses, haplotype -634C/936C and -634G/936T were associated with a decreased susceptibility of CRC (OR, 0.53 and 0.56; p<0.001, respectively). These observations imply that the VEGF gene polymorphisms may be associated with the susceptibility or clinicopathologic features of CRC. However, further studies of other VEGF sequence variants and their biological functions are needed to understand the role of the VEGF gene polymorphisms in the development and progression of CRC.

Vascular endothelial growth factor gene polymorphisms associated with prognosis for patients with colorectal cancer.

PURPOSE: Vascular endothelial growth factor (VEGF) or its family may be considered to play an important role in lymphangiogenesis and lymphatic tumor spread, thereby affecting prognosis of colorectal cancer. Accordingly, the present study analyzed VEGF gene polymorphisms and their effect on the prognosis for patients with colorectal cancer. EXPERIMENTAL DESIGN: Four hundred and forty-five consecutive patients with surgically treated colorectal adenocarcinoma were enrolled in the present study. The genomic DNA was extracted from fresh colorectal tissue and three VEGF (-2578C>A, -634G>C, and +936C>T) gene polymorphisms were determined using a PCR/denaturing high-performance liquid chromatography assay. RESULTS: Multivariate survival analysis showed that the survival for the patients with the -634 G/C genotype [overall survival (OS): hazard ratio (HR), 0.158; P < 0.001] or C/C genotype (OS: HR, 0.188; P < 0.001) were better than for the patients with the -634G/G genotype, whereas the +936 C/T genotype (OS: HR, 12.809; P < 0.001) or T/T genotype (OS: HR, 37.260; P < 0.001) was associated with a worse survival compared with the +936 C/C genotype. In haplotype analysis, the -2578A/-634G/+936T haplotype exhibited a significantly worse survival when compared with the wild -2578C/-634G/+936C haplotype (OS: HR, 3.866; P < 0.001). CONCLUSIONS: VEGF gene polymorphisms were found to be an independent prognostic marker for patients with colorectal cancer. Accordingly, the analysis of VEGF gene polymorphisms can help identify patient subgroups at high risk of a poor disease outcome.

Outpatient-basis chemotherapy of oxaliplatin, 5-fluorouracil, and leucovorin as first-line treatment for patients with metastatic or recurrent colorectal cancer.

The objectives of the present study were to evaluate the efficacy and safety of an outpatient-basis chemotherapy of oxaliplatin, 5-fluorouracil, and leucovorin as the first-line treatment for patients with advanced colorectal cancer. Forty-three histologically confirmed patients with metastatic or recurrent colorectal cancer were enrolled. The chemotherapy consisted of oxaliplatin 85 mg/m(2) as a 2-hr infusion on day 1, plus leucovorin 30 mg/m(2) over 10 min, followed by bolus 5-fluorouracil 400 mg/m(2) and an 8-hr infusion of 5-fluorouracil 600 mg/m(2) on days 1 and 2 (modified FOLFOX4), all of which were administered on an outpatient basis every 2 weeks. The median age was 58 yr (range 33-72 yr), and 25 (58.1%) patients had metastatic diseases. Eventually, 39 patients were assessable for efficacy and all assessable for toxicity. Four (9.3%) complete responses and 11 (25.6%) partial responses were confirmed, giving an overall response rate of 34.9% (95% CI; 20.0-49.7%). The median time to progression and median overall survival for all patients was 6.1 months and 17.4 months, respectively. Grade 3/4 neutropenia occurred in 2 patients (4.7%) and febrile neutropenia was observed in 1 patient (2.3%). Modified FOLFOX4, an outpatient-basis regimen, was found to be well-tolerated and effective as the first-line chemotherapy in patients with advanced colorectal cancer.