Current Status and Trends in Inflammatory Bowel Disease Surgery in Korea: Analysis of Data in a Nationwide Registry

Purpose

Inflammatory bowel disease (IBD) in Korea has been increasing in recent years, but accurate statistics about operations for IBD are lacking. The purpose of this study was to investigate the trends and current status of IBD surgeries in Korea.

Methods

Using a national database from the Korea Health Insurance Review and Assessment Service, we analyzed data from patients who underwent surgery for Crohn disease and ulcerative colitis from January 2009 to October 2016.

Results

The mean number of patients who underwent surgery for Crohn disease was 791.8 per year. Colorectal surgery, small bowel surgery, and anal surgery were performed fairly often (31.2%, 29.4%, 39.4%, respectively), and laparoscopic surgery continued to increase, recently exceeding 30%. About 50% of Crohn patients used biologics before and after surgery, and those patients also underwent a relatively high rate of anal surgeries (44.2%). The mean number of patients who underwent surgery for ulcerative colitis was 247.6 per year. Colorectal surgery accounted for more than half of all operations, and laparoscopic surgery has been increasing rapidly, having been performed in about 60% of patients in recent years. The incidence of colorectal cancer in patients with ulcerative colitis was very high and increased rapidly during the study period, reaching about 80%.

Conclusion

The number of patients undergoing laparoscopic surgery for IBD in Korea has increased significantly. Biologics are actively used by patients with Crohn disease, with a high proportion of anal surgeries required. Many of the surgical indications for ulcerative colitis have shifted into colorectal cancer.

Prognostic Implications of Extranodal Extension in Relation to Colorectal Cancer Location

Purpose

Extranodal extension (ENE) is closely associated with the aggressiveness of both colon and rectal cancer. This study evaluated the clinicopathologic significance and prognostic impact of ENE in separate populations of patients with colon and rectal cancers.

Materials and Methods

The medical records of 2,346 patients with colorectal cancer (CRC) who underwent curative surgery at our institution between January 2003 and December 2011 were clinically and histologically reviewed.

Results

ENE was associated with younger age, advanced tumor stage, lymphovascular invasion (LVI), and perineural invasion (PNI) in both colon and rectal cancer. ENE rates differed significantly in patients with right colon (36.9%), left colon (42.6%), and rectal (48.7%) cancers (right vs. left, p=0.037; left vs. rectum, p=0.009). The 5-year disease-free survival (DFS) rate according to ENE status and primary tumor site differed significantly in patients with ENE-negative colon cancer (80.5%), ENE-negative rectal cancer (77.4%), ENE-positive colon cancer (68.6%), and ENE-positive rectal cancer (64.2%) (p<0.001). Multivariate analysis showed that advanced tumor stage, ENE, LVI, PNI, and absence of adjuvant chemotherapy were independently prognostic of reduced DFS in colon and rectal cancer patients.

Conclusion

ENE is closely associated with the aggressiveness of colon and rectal cancers, with its frequency increasing from the right colon to the left colon to the rectum. ENE status is a significant independent predictor of DFS in CRC patients irrespective of tumor location. ENE might be more related with distally located CRC.

Solitary colorectal liver metastasis after curative intent surgery: prognostic factors affecting outcomes and survival

BACKGROUND

The aim of this study was to identify the prognostic factors affecting recurrence and survival in patients who underwent curative intent surgery for colorectal cancer (CRC) with a single liver metastasis.

METHODS

Between January 2006 and August 2012, we retrospectively evaluated 141 patients for CRC with single liver metastasis underwent curative intent surgery for colon and liver simultaneously. Some patients (11.3%) had radiofrequency ablation as an option.

RESULTS

The 5-year disease-free and overall survival (OS) rates were 38.9% and 59.6%, respectively. Recurrence occurred in 77 (54.6%) patients after surgery. Multivariate analysis identified node positivity and no adjuvant chemotherapy as independent risk factors for OS. We analyzed the OS risk factors in 76 recurred patients from the time of recurrence. Multivariate analysis revealed the following significant risk factors for OS after recurrence: a high serum carcinoembryonic antigen concentration at the time of recurrence, the treatment type after recurrence (chemotherapy or no treatment) and a left hepatic metastasis.

CONCLUSION

Patients who underwent a curative resection for CRC with a single liver metastasis had a relatively favourable prognosis; in these patients, node positivity and no adjuvant chemotherapy were independent prognostic factors for OS. Furthermore, a high serum carcinoembryonic antigen concentration at the time of recurrence, the treatment type after recurrence (chemotherapy or no treatment) and a left hepatic metastasis may be independent prognostic factors for OS in patients with recurrence. The left hepatic metastasis group tended to have a multiple hepatic relapse more frequently than the right hepatic metastasis group in cases of isolated hepatic relapse.

Impact of a Multidisciplinary Team Approach for Managing Advanced and Recurrent Colorectal Cancer

BACKGROUND

The wide variety of treatment strategies makes clinical decision-making difficult in advanced and recurrent colorectal cancer cases. Many hospitals have started multidisciplinary team (MDT) meetings comprising a team of dedicated specialists for discussing cases. MDTs for selected cases that are difficult to diagnose and treat are alternatives to regular MDTs. This study's aim was to determine the impact of a MDT for colorectal cancer on clinical decision-making.

METHODS

Cases were discussed when clinical specialists had difficulty making decisions alone. All processes done by the MDT were then recorded in prospectively designed medical case forms.

RESULTS

From Jan 2011 to Dec 2014, 1383 cases were discussed. A total of 549 (39.8%) case forms were completed for patients with newly diagnosed colorectal cancer, whereas 833 (60.2%) were completed for those with recurrent diseases. The MDT altered the proposed treatment of the referring physician in 179 (13%) cases. In 85 of the 179 (47.5%) altered cases, the radiologist's review of clinical information affected the diagnosis and decision. Furthermore, 152 of the 1383 MDT decisions were not implemented. Treatment intent, therapeutic plan, and alteration of decision were important reasons for not following the MDT's recommendation.

CONCLUSION

Case discussions in MDT meetings resulted in altered clinical decisions in >10% cases. Implementation rates after MDT discussions might be affected by the treatment decision-making process. Imperfect decisions made by individual physicians can be decreased by the multidisciplinary decision-making process.

An Intergenic Variant rs9268877 Between HLA-DRA and HLA-DRB Contributes to the Clinical Course and Long-term Outcome of Ulcerative Colitis

BACKGROUND AND AIMS

The genetic contribution to the prognosis of ulcerative colitis [UC] is poorly understood, and most currently known susceptibility loci are not associated with prognosis. To identify genetic variants influencing the prognosis of UC, we performed an Immunochip-based study using an extreme phenotype approach.

METHODS

Based on the finding that the only association, Pdiscovery-meta <1 × 10-4, was located in the human leukocyte antigen [HLA], we focused our analyses on the HLA region. We performed the analysis using HLA imputation data from three independent discovery cohorts of 607 UC patients [243 poor-prognosis and 364 good-prognosis], followed by replication in 274 UC patients [145 poor-prognosis and 129 good-prognosis].

RESULTS

We found that rs9268877, located between HLA-DRA and HLA-DRB, was associated with poor-prognosis of UC at genome-wide significance (odds ratio [ORdiscovery] = 1.82; ORreplication = 1.55; ORcombined-meta = 1.72, pcombined-meta = 1.04 × 10-8), with effect size [OR] increasing incrementally according to worsening of prognosis in each of the three independent discovery cohorts and the replication cohort. However, rs9268877 showed no association with UC susceptibility [ORcombined-meta = 1.07, pcombined-meta = 0.135]; rs9268877 influenced 30-year clinical outcomes, and the presence of the rs9268877 risk allele had a sensitivity of 80.0% and specificity of 38.1% for colectomy.

CONCLUSIONS

Our results provide new insights into prognosis-associated genetic variation in UC, which appears to be distinct from the genetic contribution to disease susceptibility. These findings could be useful in identifying poor-prognosis patients who might benefit from early aggressive therapy.

Prognostic Value of the Microsatellite Instability Status in Patients With Stage II/III Rectal Cancer Following Upfront Surgery

BACKGROUND

We investigated whether the microsatellite instability (MSI) status affects the survival outcomes in patients with stage II/III rectal cancer who have undergone an upfront curative resection.

PATIENTS AND METHODS

A total of 1103 patients with curatively resected stage II/III rectal cancer who had available polymerase chain reaction-based MSI results were included in the final analysis.

RESULTS

Twenty-four (2.2%) patients in the total cohort were found to be MSI-high (MSI-H). In univariate analysis, neither disease-free survival (DFS) nor overall survival (OS) demonstrated significant differences between patients with MSI-H tumors and those with MSI-low (MSI-L) or microsatellite stable (MSS) tumors. The 5-year DFS rate was 78.0% in MSI-H patients and 69.9% in MSI-L/MSS patients (hazard ratio [HR], 0.84; 95% confidence interval [CI], 0.35-2.02; P = .689). The 5-year OS rates for MSI-H and MSI-L/MSS patients were 84.0% and 83.1%, respectively (HR, 0.86; 95% CI, 0.27-2.69; P = .790). By multivariate analysis, the MSI status did not affect either the DFS (HR, 1.00; 95% CI, 0.40-2.47; P = .994) or OS (HR, 0.85; 95% CI, 0.26-2.73; P = .778).

CONCLUSIONS

MSI-H tumors are rarely observed in rectal adenocarcinoma, and the MSI status may not affect the survival outcome in patients with a resected rectal cancer.

Magnetic resonance tumour regression grade and pathological correlates in patients with rectal cancer

BACKGROUND

Evidence to support the specific use of magnetic resonance tumour regression grade (mrTRG) is inadequate. The aim of this study was to investigate the pathological characteristics of mrTRG after chemoradiotherapy (CRT) for rectal cancer and the implications for surgery.

METHODS

Patients undergoing long-course CRT (45-50 Gy plus a booster dose of 4-6 Gy) for mid or low rectal cancer (cT3-4 or cN+ without metastasis) between 2011 and 2015 who had post-CRT rectal MRI before surgery were included retrospectively. Three board-certified experienced radiologists assessed mrTRG. mrTRG was correlated with pathological tumour regression grade (pTRG), ypT and ypN. In a subgroup of patients with mrTRG1-2 and no tumour spread (such as nodal metastasis) on MRI, the projected rate of completion total mesorectal excision (TME) if they underwent transanal excision (TAE) and had a ypT status of ypT2 or higher was estimated, and recurrence-free survival was calculated according to the operation (TME or TAE) that patients had actually received.

RESULTS

Some 439 patients (290 men and 149 women of mean(s.d.) age 62·2(11·4) years) were analysed. The accuracy of mrTRG1 for predicting pTRG1 was 61 per cent (40 of 66), and that for ypT1 or less was 74 per cent (49 of 66). For mrTRG2, these values were 22·3 per cent (25 of 112) and 36·6 per cent (41 of 112) respectively. Patients with mrTRG1 and mrTRG2 without tumour spread were ypN+ in 3 per cent (1 of 29) and 16 per cent (8 of 50) respectively. Assuming mrTRG1 or mrTRG1-2 with no tumour spread on post-CRT MRI as the criteria for TAE, the projected completion TME rate was 26 per cent (11 of 43) and 41·0 per cent (41 of 100) respectively. For the 100 patients with mrTRG1-2 and no tumour spread, recurrence-free survival did not differ significantly between TME (79 patients) and TAE (21) (adjusted hazard ratio 1·86, 95 per cent c.i. 0·42 to 8·18).

CONCLUSION

Patients with mrTRG1 without tumour spread may be suitable for TAE.

Trephine Transverse Colostomy Is Effective for Patients Who Have Previously Undergone Rectal Surgery

Purpose

Colostomy creation is an essential procedure for colorectal surgeons, but the preferred method of colostomy varies by surgeon. We compared the outcomes of trephine colostomy creation with open those for the (laparotomy) and laparoscopic methods and evaluated appropriate indications for a trephine colostomy and the advantages of the technique.

Methods

We retrospectively evaluated 263 patients who had undergone colostomy creation by trephine, open and laparoscopic approaches between April 2006 and March 2016. We compared the clinical features and the operative and postoperative outcomes according to the approach used for stoma creation.

Results

One hundred sixty-three patients (62%) underwent colostomy surgery for obstructive causes and 100 (38%) for fistulous problems. The mean operative time was significantly shorter with the trephine approach (trephine, 46.0 ± 1.9 minutes; open, 78.7 ± 3.9 minutes; laparoscopic, 63.5 ± 5.0 minutes; P < 0.001), as was the time to flatus (1.8 ± 0.1 days, 2.1 ± 0.1 days, 2.2 ± 0.3 days, P = 0.025). Postoperative complications (<30 days) were not different among the 3 approaches (trephine, 4.3%; open, 1.2%; laparoscopic, 0%; P = 0.828). In patients who underwent rectal surgery, a trephine colostomy was feasible for a diversion colostomy (P < 0.001).

Conclusion

The trephine colostomy is safe and can be implemented quickly in various situations, and compared to other colostomy procedures, the patient’s recovery is faster. Previous laparotomy history was not a contraindication for a trephine colostomy, and a trephine transverse colostomy is feasible for patients who have undergone previous rectal surgery.

Primary malignant melanoma of the small intestine: a report of 2 cases and a review of the literature

The majority of malignant melanomas in the small intestine are metastases from primary cutaneous lesions, it can also develop as a primary mucosal tumor in the gastrointestinal tract. In this report, we present rare cases of primary small bowel melanoma and review the current literature. A 78-year-old male presented with abdominal pain and CT enterography identified a ileal mass. A 79-year-old female presented with signs and symptoms of partial small bowel obstruction. Abdominopelvic CT and small bowel series revealed a obstructing mass in the distal jejunum. The masses were confirmed on laparotomy and histologically diagnosed as melanoma. Extensive postoperative clinical examination revealed no cutaneous lesions. A primary small bowel melanoma is an extremely rare neoplasm. A definite diagnosis can only be made after a thorough investigation has been made to exclude the coexistence of a primary lesion. Curative resection of the tumor remains the treatment of choice.

Landscape of Actionable Genetic Alterations Profiled from 1,071 Tumor Samples in Korean Cancer Patients

Purpose

With the emergence of next-generation sequencing (NGS) technology, profiling a wide range of genomic alterations has become a possibility resulting in improved implementation of targeted cancer therapy. In Asian populations, the prevalence and spectrum of clinically actionable genetic alterations has not yet been determined because of a lack of studies examining high-throughput cancer genomic data.

Materials and Methods

To address this issue, 1,071 tumor samples were collected from five major cancer institutes in Korea and analyzed using targeted NGS at a centralized laboratory. Samples were either fresh frozen or formalin-fixed, paraffin embedded (FFPE) and the quality and yield of extracted genomic DNA was assessed. In order to estimate the effect of sample condition on the quality of sequencing results, tissue preparation method, specimen type (resected or biopsied) and tissue storage time were compared.

Results

We detected 7,360 non-synonymous point mutations, 1,164 small insertions and deletions, 3,173 copy number alterations, and 462 structural variants. Fifty-four percent of tumors had one or more clinically relevant genetic mutation. The distribution of actionable variants was variable among different genes. Fresh frozen tissues, surgically resected specimens, and recently obtained specimens generated superior sequencing results over FFPE tissues, biopsied specimens, and tissues with long storage duration.

Conclusion

In order to overcome, challenges involved in bringing NGS testing into routine clinical use, a centralized laboratory model was designed that could improve the NGS workflows, provide appropriate turnaround times and control costs with goal of enabling precision medicine.

Local excision for ypT2 rectal cancer following preoperative chemoradiation therapy: it should not be justified

PURPOSE

Among individuals who respond well to preoperative chemoradiation therapy (CRT) for ypT0-1, local excision (LE) could provide acceptable oncological outcomes. However, in ypT2 cases, the oncological safety of LE has not been determined. This study aimed to compare oncological outcomes between LE and total mesorectal excision of ypT2-stage rectal cancer after chemoradiation therapy and investigate the oncological safety of LE in these patients.

METHODS

We included 351 patients who exhibited ypT2-stage rectal cancer after CRT followed by LE (n = 16 [5%]) or total mesorectal excision (TME) (n = 335 [95%]) after preoperative CRT between January 2007 and December 2013. After propensity matching, oncological outcomes between LE group and TME group were compared.

RESULTS

The median follow-up period was 57 months (range, 12-113 months). In the LE group, local recurrence occurred more frequently (18 vs. 4%; p = 0.034) but not distant metastases (12 vs. 11%; p = 0.690). The 5-year local recurrence-free (76 vs. 96%; p = 0.006), disease-free (64 vs. 84%; p = 0.075), and overall survival (79 vs. 93%; p = 0.045) rates of the LE group were significantly lower than those of the TME group. After propensity matching, 5-year local recurrence-free survival of the LE group was significantly lower than that of the TME group (76 vs. 97%, p = 0.029).

CONCLUSION

The high local failure rate and poor oncological outcomes for ypT2-stage rectal cancer patients who undergo CRT followed by LE cannot be justified as an indication for LE. Salvage surgery should be recommended in these patients.

Utility of BRAF VE1 Immunohistochemistry as a Screening Tool for Colorectal Cancer Harboring BRAF V600E Mutation

Background

BRAF mutation has been recognized as an important biomarker of colorectal cancer (CRC) for targeted therapy and prognosis prediction. However, sequencing for every CRC case is not cost-effective. An antibody specific for BRAF V600E mutant protein has been introduced, and we thus examined the utility of BRAF VE1 immunohistochemistry for evaluating BRAF mutations in CRC.

Methods

Fifty-one BRAF-mutated CRCs and 100 age and sexmatched BRAF wild-type CRCs between 2005 and 2015 were selected from the archives of Asan Medical Center. Tissue microarrays were constructed and stained with BRAF VE1 antibody.

Results

Forty-nine of the 51 BRAF-mutant CRCs (96.1%) showed more than moderate cytoplasmic staining, except for two weakly stained cases. Six of 100 BRAF wild-type cases also stained positive with BRAF VE1 antibody; four stained weakly and two stained moderately. Normal colonic crypts showed nonspecific weak staining, and a few CRC cases exhibited moderate nuclear reactivity (3 BRAF-mutant and 10 BRAF wild-type cases). BRAF-mutated CRC patients had higher pathologic stages and worse survival than BRAF wild-type patients.

Conclusions

BRAF VE1 immunohistochemistry showed high sensitivity and specificity, but occasional nonspecific staining in tumor cell nuclei and normal colonic crypts may limit their routine clinical use. Thus, BRAF VE1 immunohistochemistry may be a useful screening tool for BRAF V600E mutation in CRCs, provided that additional sequencing studies can be done to confirm the mutation in BRAF VE1 antibody-positive cases.

Post-pulmonary metastasectomy prognosis after curative resection for colorectal cancer

Purpose

We aimed to compare disease-free survival after pulmonary metastasectomy to that after hepatic metastasectomy, and to identify prognostic factors after pulmonary metastasectomy.

Results

Between 2005 and 2015, 129 patients underwent resection of isolated metachronous lung metastases from colorectal cancer. Three-year DFS after pulmonary metastasectomy was similar to that after hepatic metastasectomy (50.7% vs. 45.5%, respectively; p=0.58). Rectal cancer (hazard ratio [HR]: 2.04, 95% confidence interval [CI]: 1.09–3.79; p=0.03) and ≥2 metastases (HR: 2.17, 95% CI: 1.28–3.68; p=0.004) were independent adverse risk factors associated with disease-free survival after pulmonary metastasectomy on multivariate analysis. Three-year DFS for colon vs. rectal cancer patients was 72.5% vs. 42.6%, respectively (p=0.04). The number of lung metastases was an independent risk factor for DFS after pulmonary metastasectomy in rectal cancer patients.

Patients and Methods

Patients who underwent lung metastasectomy after curative resection of colorectal cancers were investigated. Disease-free survival (DFS) after pulmonary metastasectomy was compared to that after hepatic metastasectomy, which has a relatively well-known prognosis. Multivariate Cox proportional hazards analysis was performed to identify clinical variables predictive of survival after pulmonary metastasectomy.

Conclusions

Disease-free survival rates after resection of lung vs. liver metastases arising from colorectal cancers are similar. However, lung metastases specifically from rectal cancers produce poorer DFS rates. Primary tumor location must be considered for pulmonary metastasis treatment and follow-up in colorectal cancer patients.

Chronic hepatitis B infection and non-hepatocellular cancers: A hospital registry-based, case-control study

Background

Prior epidemiological evidences suggest that hepatitis B virus (HBV) infection is linked to cancers other than hepatocellular carcinoma. This prospective hospital registry-based case-control study aimed to investigate the sero-epidemiological association between chronic HBV infection and various types of cancer.

Methods

95,034 patients with first-diagnosed non-hepatocellular malignancy in a tertiary hospital between 2007 and 2014; and 118,891 non-cancer individuals as controls from a health promotion center were included. Cases and controls were compared for HBV surface antigen (HBsAg) positivity by conditional regression with adjustment for age, hypertension, diabetes, body mass index, alcohol consumption, smoking status and cholesterol level in both genders.

Results

An analysis of matched data indicated significant associations of HBV infection with lymphoma (adjusted odds ratio[AOR] 1.53 [95% CI 1.12–2.09] in men and 3.04 [1.92–4.82] in women) and biliary cancer (2.59[1.98–3.39] in men and 1.71[1.16–2.51] in women). Cervical (1.49[1.11–2.00]), uterine (1.69[1.09–2.61]), breast (1.16[1.02–1.32]), thyroid (1.49[1.28–1.74]), and lung cancers (1.79[1.32–2.44]) in women; and skin cancer (5.33[1.55–18.30]) in men were also significantly related to HBV infection.

Conclusions

Chronic HBV infection is associated with several malignant disorders including lymphoma, and biliary, cervical, uterine, breast, thyroid, lung, and skin cancers. Our findings may offer additional insights into the development of these neoplasms and may suggest the need to consider HBV screening in cancer patients and cancer surveillance in HBV-infected subjects.

Is the pathological regression level of metastatic lymph nodes associated with oncologic outcomes following preoperative chemoradiotherapy in rectal cancer?

Purpose

The oncologic impact of the lymph node (LN) regression level after preoperative chemoradiotherapy (PCRT) has not been thoroughly evaluated. Hence, this study aimed to examine whether the regression level of metastatic LNs following PCRT is associated with oncologic outcomes in rectal cancer.

Results

The optimal number of cut points for LRG sum was determined to be three. The three LRG groups demonstrated different distributions according to the ypT and ypN stages (p < 0.001 for both). However, the distribution of the LRG groups was not associated with the TRG of the primary tumor (p = 0.527). The RFS significantly differed according to the LRG groups (p = 0.001). Moreover, the differences in RFS remained when the LRG groups were analyzed within each separate ypN stage. The LRG group was confirmed as a factor associated with RFS in the multivariate analysis (p=0.018), while the ypN stage was not (p=0.4).

Patients and Methods

We analyzed the outcomes of 142 rectal cancer patients diagnosed with ypN1 disease after PCRT followed by radical resection. The pathological responses of the primary tumor and LNs to PCRT were evaluated using the tumor regression grade (TRG) and LN regression grade (LRG), respectively. The impact of LRG on recurrence-free survival (RFS) was analyzed. The K-adaptive partitioning for survival data method was applied to determine the optimal number of cut points for the LRG-sum and the optimal number of subgroups.

Conclusion

The LRG as an indicator of response to PCRT should be considered as a prognostic determinant in rectal cancer patients. Future large-scale prospective studies are needed to confirm this finding.

Incidence and risk factors of postoperative pneumonia following cancer surgery in adult patients with selected solid cancer: results of "Cancer POP" study

The aim of this study was to investigate the incidence and risk factors of postoperative pneumonia (POP) within 1 year after cancer surgery in patients with the five most common cancers (gastric, colorectal, lung, breast cancer, and hepatocellular carcinoma [HCC]) in South Korea. This was a multicenter and retrospective cohort study performed at five nationwide cancer centers. The number of cancer patients in each center was allocated by the proportion of cancer surgery. Adult patients were randomly selected according to the allocated number, among those who underwent cancer surgery from January to December 2014 within 6 months after diagnosis of cancer. One‐year cumulative incidence of POP was estimated using Kaplan–Meier analysis. An univariable Cox's proportional hazard regression analysis was performed to identify risk factors for POP development. As a multivariable analysis, confounders were adjusted using multiple Cox's PH regression model. Among the total 2000 patients, the numbers of patients with gastric cancer, colorectal cancer, lung cancer, breast cancer, and HCC were 497 (25%), 525 (26%), 277 (14%), 552 (28%), and 149 (7%), respectively. Overall, the 1‐year cumulative incidence of POP was 2.0% (95% CI, 1.4–2.6). The 1‐year cumulative incidences in each cancer were as follows: lung 8.0%, gastric 1.8%, colorectal 1.0%, HCC 0.7%, and breast 0.4%. In multivariable analysis, older age, higher Charlson comorbidity index (CCI) score, ulcer disease, history of pneumonia, and smoking were related with POP development. In conclusions, the 1‐year cumulative incidence of POP in the five most common cancers was 2%. Older age, higher CCI scores, smoker, ulcer disease, and previous pneumonia history increased the risk of POP development in cancer patients.

Anastomotic Recurrence After Curative Resection for Colorectal Cancer

BACKGROUND

A precise understanding of anastomotic recurrence (AR) permits efficient surveillance and treatment strategies. This study aimed to evaluate the clinicopathologic characteristics of patients with AR undergoing curative resection for colorectal cancer (CRC), compare colonic with rectal tumors and investigate the risk factors related to AR.

METHODS

A single-institution, retrospective cohort of 9024 patients who underwent curative surgery for CRC between 2000 and 2010 was enrolled. Patients were classified into AR group (n = 53) or non-AR group (n = 8971) and were also characterized by tumor location.

RESULTS

The AR group was independently associated with old age (p = 0.046), advanced N stage (p = 0.003), the rectum (p = 0.001), a large tumor (p = 0.001) and mucinous differentiation (MU) (p = 0.026). In colon cancers, the AR group (n = 20) was independently associated with MU (p = 0.022) and lymphovascular invasion (LVI) (p = 0.001). In rectal cancers, the AR group (n = 33) was independently associated with N2 stage (p = 0.007) and a large tumor (p < 0.001). AR is a burden to patients and physicians because these tumors have a poor prognosis and more advanced pathologic stages than the primary tumors. However, N0 stage and curative resection of an AR tumor (p = 0.001 and p < 0.001, respectively) were found to be independently associated with improved survival in a Cox regression model.

CONCLUSION

AR is independently associated with the rectum. In colon cancers, MU and LVI are independent risk factors for AR. In rectal cancers, a large tumor and N2 stage are independent risk factors for AR. Although AR shows a poor prognosis, early detection and curative resection may lead to an improved survival.

Does Anastomosis Configuration Influence Long-term Outcomes in Patients With Crohn Disease?

Purpose

In this study, we evaluated the role of various anastomoses in surgical recurrence for patients with Crohn disease (CD).

Methods

We analyzed data retrospectively from consecutive laparotomy cases involving complicated CD between 1991 and 2008. Clinical data were compared in terms of reoperation-free survival (RFS) according to the types of anastomoses, the materials used for the anastomoses, and the operating surgeon.

Results

Of 233 patients with entero-enteric or entero-colic anastomoses, 199 (85%), 11 (5%), and 23 (10%) experienced side-to-side (SS), side-to-end (SE), and end-to-end (EE) anastomoses, respectively. The SS group had the following characteristics: more extensive bowel involvement, frequent obstruction, and greater stapler use; the SS anastomoses were also frequently made by specialized surgeons (P < 0.001–0.004). EE anastomoses were frequently made by general surgeons using a hand-sewing technique (P < 0.001). No differences in RFS were noted among the 3 groups according to the type of anastomosis and the operating surgeon. However, the hand-sewn group showed better RFS than the stapler group (P = 0.04).

Conclusion

The roles of the anastomotic configuration, the material used, and the operating surgeon were not significantly correlated with reoperations or complications in our retrospective CD cohort, irrespective of the higher risk of anastomosis site stricture for EE anastomoses.

Risk factors for postoperative recurrence after primary bowel resection in patients with Crohn’s disease

AIM

To evaluate the risk factors for postoperative recurrence after primary bowel resection in a cohort of Korean Crohn’s disease (CD) patients.

METHODS

This study included 260 patients with no history of previous bowel surgery who underwent primary surgery for CD between January 2000 and December 2010 at Asan Medical Center (Seoul, South Korea). The median follow-up period was 101 mo.

RESULTS

During the follow-up period, 66 patients (25.4%) underwent a second operation for disease recurrence. At 1, 5 and 10 years after the first operation, the cumulative rate of surgical recurrence was 1.1%, 8.3% and 35.9% and clinical recurrence occurred in 1.2%, 23.6% and 68.1%, respectively. In multivariate analysis, undergoing an emergency operation was a significant risk factor for surgical recurrence-free survival (SRFS) [HR = 2.431, 95%CI: 1.394-4.240, P = 0.002], as were the presence of perianal disease after the first operation (HR = 1.715, 95%CI: 1.005-2.926, P = 0.048) and history of smoking (HR = 1.798, 95%CI: 1.088-2.969, P = 0.022). The postoperative use of anti-tumor necrosis factor (TNF) agents reduced SRFS risk (HR = 0.521, 95%CI: 0.300-0.904, P = 0.02).

CONCLUSION

History of smoking, postoperative perianal disease and undergoing an emergency operation were independent risk factors for surgical recurrence. Using anti-TNF agents may reduce surgical recurrence.

Peri-treatment change of anorectal function in patients with rectal cancer after preoperative chemoradiotherapy

Preoperative chemoradiotherapy (PCRT) is a standard treatment for locally advanced rectal cancer. The influence of PCRT on anorectal function has not been objectively assessed. We evaluated the short-term influence of PCRT on anorectal function in patients with locally advanced rectal cancer using anorectal manometry. We included 310 patients with locally advanced mid and lower rectal cancer who underwent PCRT from 2012 to 2015. We compared anorectal function based on anorectal manometry between before and after PCRT according to tumor location, clinical T (cT) stage, and tumor response after PCRT. Lower rectal cancer was common in the cohort of 310 patients (n = 228, 73.5%). Sphincter length (p = 0.003) and maximal resting pressure (p < 0.001) increased and maximal tolerated volume (p = 0.036) decreased after PCRT regardless of tumor location. Maximal squeezing pressure and rectal compliance slightly decreased, without statistical significance. Changes in manometric parameters after PCRT were not associated with changes of cT stage after PCRT. However, minimal sensory volume (p = 0.042) and maximal tolerated volume (p = 0.025) increased significantly in 143 patients (46.1%) with changes in the distance of the cancer from the anal verge after PCRT. PCRT did not impair the overall short-term anorectal manometric parameters in patients with locally advanced rectal cancer. Further study is required to investigate postoperative anorectal function after sphincter-preserving surgery to evaluate the long-term effects of PCRT on anorectal function.

Outcomes of patients with abdominoperineal resection (APR) and low anterior resection (LAR) who had very low rectal cancer

We compared the oncological outcomes of sphincter-saving resection (SSR) and abdominoperineal resection (APR) in 409 consecutive patients with very low rectal cancer (i.e., tumors within 3 cm from the anal verge); 335 (81.9%) patients underwent APR and 74 (18.1%) underwent SSR. The APR group comprised higher proportions of men (67.5% vs 55.4%, P = .049) and advanced-stage patients (P < .001). Preoperative chemoradiotherapy (PCRT) was more frequently administered in the SSR group (83.8% vs 52.8%, P < .001). Overall, the systemic and local recurrence rates were 29.1% and 6.1%, respectively. On stratification according to PCRT and pathologic stage, the mode of surgery did not affect the recurrence type. Moreover, recurrence-free survival (RFS) did not differ according to the mode of surgery in different cancer stages. RFS was associated with ypT and ypN stages in patients who received PCRT, while pN stage, lymphovascular invasion (LVI), and circumferential resection margin (CRM) involvement were risk factors for RFS in those who did not receive PCRT. Notably, SSR was not found to be a risk factor for RFS in either subgroup. Patients who were stratified according to cancer stage and PCRT also showed no differences in RFS according to the mode of surgery. Our results demonstrate that, regardless of PCRT administration, SSR is an effective treatment for very low rectal cancer, while CRM is an important prognostic factor for patients who did not receive PCRT.

The long-term outcomes of recurrent adhesive small bowel obstruction after colorectal cancer surgery favor surgical management

An adhesive small bowel obstruction (ASBO) is generally caused by postoperative adhesions and is more frequently associated with colorectal surgeries than other procedures. We compared the outcomes of operative and conservative management of ASBO after primary colorectal cancer surgery.We retrospectively reviewed 5060 patients who underwent curative surgery for primary colorectal cancer; 388 of these patients (7.7%) were readmitted with a diagnosis of SBO. We analyzed the clinical course of these patients with reference to the cause of their surgery.Of the 388 SBO patients analyzed, 170 were diagnosed with ASBO. Their 3-, 5-, and 7-year recurrence-free survival rates were 86.1%, 72.8%, and 61.5%, respectively. The median follow-up period was 59.2 months. Repeated conservative management for ASBO without surgical management led to higher recurrence rates: 21.0% after the first admission, 41.7% after the second, 60.0% after the third, and 100% after the fourth (P = .006). Surgical management was needed for 19.2%, 22.2%, 50%, and 66.7% of patients admitted with ASBO on the first to fourth hospitalizations, respectively. Repeated hospitalization for obstruction led to a greater possibility of surgical management (P = .001). Of 27 patients with surgical management at the first admission, 6 (17.6%) were readmitted with a diagnosis of SBO, but there were no further episodes of SBO in the surgically managed patients.Patients who undergo operative management for ASBO have a reduced risk of recurrence requiring hospitalization, whereas those with repeated conservative management have an increased risk of recurrence and require operative management. Operative management should be considered for recurrent SBO.

CT Enterography for Surveillance of Anastomotic Recurrence within 12 Months of Bowel Resection in Patients with Crohn's Disease: An Observational Study Using an 8-Year Registry

OBJECTIVE

To investigate the diagnostic yield and accuracy of CT enterography (CTE) for early (< 12 postoperative months) surveillance of anastomotic recurrence after bowel resection for Crohn's disease (CD).

MATERIALS AND METHODS

We analyzed 88 adults (60 males and 28 females; mean age, 31.4 ± 9.6 years) who underwent bowel surgery for CD that created ileocolic anastomosis without enteric stoma, and underwent CTE for surveillance of CD recurrence/aggravation within 12 post-operative months. The CD activity index (CDAI) at the time of CTE was < 150 (i.e., clinically silent) in 51 patients, and ≥ 150 in 37 patients. Diagnostic yields of CTE regarding CD recurrence in the ileocolic anastomosis and extraluminal penetrating complications were determined. CTE-related step-up therapy was recorded. These outcomes were compared between the two CDAI groups after accounting for major risk factors for CD recurrence. In a subgroup of 31 patients who underwent both CTE and ileocolonoscopy within 1 month, CTE accuracy for anastomotic recurrence was assessed using the Rutgeerts scoring as the reference standard.

RESULTS

CTE diagnostic yield was 35.2% (31/88) for the anastomotic recurrence and 9.1% (8/88) for penetrating complications. 20.5% (18/88) of the patients underwent step-up therapy after CTE detection of anastomotic recurrence. These outcomes were not significantly different between CDAI < 150 and CDAI ≥ 150, except that CTE yield for extraluminal penetrating complications was significantly higher in CDAI ≥ 150 (16.2% [6/37] vs. 3.9% [2/51]; multivariable-adjusted p = 0.029). CTE showed 92.3% (12/13) sensitivity and 83.3% (15/18) specificity for anastomotic recurrence.

CONCLUSION

CTE may be a viable option for the early postsurgical surveillance of recurred disease in CD patients.

Oncologic significance of para-aortic lymph node and inferior mesenteric lymph node metastasis in sigmoid and rectal adenocarcinoma

BACKGROUND

Recurrence patterns or survival in colorectal cancer patients might differ according to inferior mesenteric lymph node (IMLN) metastasis. However, few studies have compared para-aortic lymph node (PALN) metastasis and IMLN metastasis. The aim of the current study is to identify survival and recurrence patterns in patients with sigmoid colon and rectal adenocarcinoma with either PALN or IMLN metastasis and to evaluate the prognostic significance of PALN and IMLN metastasis.

METHODS

A retrospective study involving 3076 patients with stage III and IV sigmoid and rectal cancer, who underwent curative surgery between January 2000 and December 2009, was performed. Clinicopathologic features, recurrence patterns, and survival outcomes of 27 patients with PALN metastasis were compared with those of 47 patients with IMLN metastasis. Patients with both IMLN and PALN metastasis were included in the PALN+ group.

RESULTS

After curative resection, there was no significant difference in the 5-year disease-free and overall survival rates between the PALN+ and IMLN+ groups (27.5% vs. 29.8%, p = 0.24, and 37% vs. 39.2%, p = 0.19, respectively). Furthermore, there were no significant differences in recurrence rate (PALN+ group, 70.4%; and IMLN+ group, 63.8%; p = 0.69) or recurrence patterns.

CONCLUSIONS

The results suggest that IMLN metastasis, similar to PALN metastasis, is associated with adverse oncologic outcomes and has prognostic significance. Therefore, it is preferable that IMLN metastasis should be considered under the category of systemic metastasis (M1).

Postoperative changes of manometry after restorative proctocolectomy in Korean ulcerative colitis patients

AIM

To investigate the changes of postoperative anal sphincter function and bowel frequency in Korean patients with ulcerative colitis (UC).

METHODS

A total of 127 patients with UC who underwent restorative proctocolectomy (RPC) during 20 years were retrospectively analyzed. The parameters of anal manometry and bowel frequency were compared according to the 6-mo intervals until 24 mo postoperatively. Manometry was used to measure the maximal squeezing pressure (MSP) and maximal resting pressure (MRP).

RESULTS

MSP decreased after surgery until 6 mo (157 to 142 mmHg); thereafter, it improved and was recovered to and maintained at the preoperative value at 12 mo postoperatively (142-170 mmHg, P < 0.001). Although the decreased MRP (65 to 56 mmHg) improved after 18 mo (62 mmHg), it did not completely recover to the preoperative value. The decreased rectal capacity after surgery (90 to 82 mL) gradually increased up to 150 mL at 24 mo. Although bowel frequency showed significant gradual decreases at each interval, it was stabilized after 12 mo postoperatively (6.5 times/d).

CONCLUSION

Postoperative changes of manometry and bowel frequency after restorative proctocolectomy in Korean patients with UC were not different from those in Western patients with UC.