Pathway cross-talk network strategy reveals key pathways in non-small cell lung cancer.

PURPOSE: The purpose of this study was to explore the pathway cross-talks and key pathways in non-small cell lung cancer (NSCLC) to better understand the underlying pathological mechanism. METHODS: Integrated gene expression data, pathway data and protein-protein interaction (PPI) data were assessed to identify the pathway regulatory interactions in NSCLC, and constructed the background and disease pathway crosstalk networks, respectively. In this work, the attractor method was implemented to identified the differential pathways, and the rank product (RP) algorithm was used to determine the importance of pathways. RESULTS: Based on 787,896 PPI interactions from STRING database and 300 human pathways from KEGG, we constructed the back pathway cross-talk network with 300 nodes and 42239 edges. Integrating with expression data of NSCLC, each pathway cross-talk endowed with a weight value, and disease pathway cross-talks were identified. By RP algorithm and topology analysis of network, we selected 5 key pathways, including Alanine, DNA replication, Fanconi anemia pathway, Cell cycle and MicroRNAs in cancer under the pre-set thresholds. CONCLUSION: We successfully revealed the disease pathway cross-talks and explored 5 key pathways in NSCLC, which may be the underlying therapeutic targets for lung cancer.

MiRNA-155 and miRNA-132 as potential diagnostic biomarkers for pulmonary tuberculosis: A preliminary study.

In our study, we aimed to profile a panel microRNAs (miRNAs) as potential biomarkers for the early diagnosis of pulmonary tuberculosis (PTB) and to illuminate the molecular mechanisms in the development of PTB. Firstly, gene expression profile of E-GEOD-49951 was downloaded from ArrayExpress database, and quantile-adjusted conditional maximum likelihood method was utilized to identify statistical difference between miRNAs of Mycobacterium tuberculosis (MTB)-infected individuals and healthy subjects. Furthermore, in order to assess the performance of our methodology, random forest (RF) classification model was utilized to identify the top 10 miRNAs with better Area Under The Curve (AUC) using 10-fold cross-validation method. Additionally, Monte Carlo Cross-Validation was repeated 50 times to explore the best miRNAs. In order to learn more about the differentially-expressed miRNAs, the target genes of differentially-expressed miRNAs were retrieved from TargetScan database and Ingenuity Pathways Analysis (IPA) was used to screen out biological pathways where target genes were involved. After normalization, a total of 478 miRNAs with higher than 0.25-fold quantile average across all samples were required. Based on the differential expression analysis, 38 differentially expressed miRNAs were identified when the significance was set as false discovery rate (FDR) < 0.01. Among the top 10 differentially expressed miRNAs, miRNA-155 obtained a highest AUC value 0.976, showing a good performance between PTB and control groups. Similarly, miRNA-449a, miRNA-212 and miRNA-132 revealed also a good performance with AUC values 0.947, 0.931 and 0.930, respectively. Moreover, miRNA-155, miRNA-449a, miRNA-29b-1* and miRNA-132 appeared in 50, 49, 49 and 48 bootstraps. Thus, miRNA-155 and miRNA-132 might be important in the progression of PTB and thereby, might present potential signatures for diagnosis of PTB.

Integrating differential pathway analysis with Monte Carlo cross-validation reveals seed cross-talks in non-small cell lung carcinoma.

PURPOSE: The objective of this study was to identify seed pathway cross-talks in non-small cell lung carcinoma (NSCLC), and to reveal potential pathological mechanism at molecular level systematically. METHODS: Differentially expressed genes (DEGs) between NSCLC and normal controls were identified using quantile- adjusted conditional maximum likelihood (QCML) method. Subsequently, differential pathways (DPs) enriched by DEGs were determined according to the Ingenuity Pathways Analysis )IPA) pathways and Fisher's exact test. A discriminating score )DS) was computed for each pair of DPs also called as cross-talk, and random forest )RF) algorithm was implemented to investigated hub cross-talks. Finally, global cross-talks with repeated times > 5 were calculated by Monte Carlo Cross-Validation )MCCV). By taking intersections between hub cross-talks and global crosstalks, we obtained seed cross-talks. RESULTS: We obtained 122 DEGs and 5 DPs between NSCLC samples and normal controls. Based on DS and RF algorithm, 5 hub cross-talks with best area under the curve )AUC) were identified, of which Agranulocyte Adhesion and Diapedesis, and IL-17A Signaling in Fibroblasts were the best with AUC=0.996. After intersected with global cross-talks, we gained 2 seed cross-talks (Agranulocyte Adhesion and Diapedesis, Granulocyte Adhesion and Diapedesis and Agranulocyte Adhesion and Diapedesis, Glutathione Redox Reactions I). CONCLUSIONS: Two seed cross-talks were identified and validated by MCCV, which may give insights for revealing pathological mechanism and potential biomarkers for target therapy in NSCLC.

Surgical management of leiomyosarcoma of the inferior vena cava.

The optimal surgical management of patients with leiomyosarcoma of inferior vena cava remains a controversy. From 1975 and 2009, five patients with leiomyosarcoma of inferior vena cava were treated at the Chinese PLA General Hospital and Beijing Shijitan Hospital. The age ranged 39-61 years and the duration of symptoms ranged from 18 to 36 months. Abdominal and back pain are the most common complaints. A combination of various imaging modalities is essential for treatment planning. R0, R1, R2, and biopsy only were accomplished in 2, 1, 1, and 1 case, respectively. Combined resections included inferior vena cava, right kidney, adrenal gland, psoas, colon, duodenal, gallbladder, liver, and/or aorta, without inferior vena cava reconstruction. No inferior vena cava-related postoperative complication was seen in our series.

High microvessel and lymphatic vessel density predict poor prognosis in patients with esophageal squamous cell carcinoma.

Background: Microangiogenesis and lymphangiogenesis are essential for tumor growth in the tumor microenvironment, contributing to tumor invasion and metastasis. Limited literature exists on these processes in esophageal squamous cell carcinoma (ESCC). Therefore, the purpose of this study is to explore the impacts of microangiogenesis and lymphangiogenesis on the occurrence, progression, and prognosis assessment of ESCC. Methods: Surgical specimens and paraffin-embedded human tissues were procured from ESCC patients, encompassing 100 ESCC tissues and 100 cancer-adjacent normal (CAN) tissues. CD34 and D2-40 were utilized as markers for microvessel endothelial cells and lymphatic vessel endothelial cells, respectively. Microvascular density (MVD) and lymphatic vessel density (LVD) were evaluated through immunohistochemical quantification. Results: We found that tumor tissues in ESCC patients had significantly higher MVD and LVD than cancer-adjacent normal (CAN) tissues. High MVD and LVD were associated with lymph node metastasis and advanced tumor clinical stages. Additionally, both high MVD and high LVD were strongly linked to poorer prognosis among cancer patients. Furthermore, a positive correlation was found between high MVD and high LVD (p < 0.05). The presence of these markers individually indicated a worse prognosis, with their combined assessment showcasing enhanced prognostic value. Conclusions: Overall, the increased MVD and LVD indicates higher invasion and metastasis of ESCC, closely correlating with unfavorablefor poor prognosis of ESCC patients.

Risk factors for recurrence and survival in patients with primary retroperitoneal tumors.

PURPOSE: Postoperative recurrence remains the major cause of death in patients with primary retroperitoneal tumors (PRT). This study aimed at investigating the potential biological and surgical factors associated with postoperative recurrence and survival in PRT patients. METHODS: Retrospective data were collected from 231 PRT patients from January 1980 and December 2005 from the General Hospital of PLA and Beijing Shijitan Hospital. Recurrence-free survival (RFS) was determined with the Kaplan-Meier method and Cox model. Clinicopathologocal and surgical variables were analyzed to determine their impact on the outcome of PRT. RESULTS: The median follow-up period was 35 months (range 1-221). The most common histological subtype was liposarcoma (N=93, 40.3%), followed by malignant fibrous histiocytoma (MFH; N=46, 19.9%). Eighty-eight patients had local recurrence (71%) and 36 (29%) developed distant metastasis. On multivariate analysis, the surgical margin status and histological type were associated with postoperative recurrence. Patients with liposarcoma and MFH had significantly increased postoperative recurrence rate (p=0.008 and p=0.002, respectively). The overall survival in PRT patients was comparable between the incomplete resection group and the complete resection group (p=0.060), but significantly associated with the surgical resection (p=0.045). CONCLUSIONS: Our results demonstrate that high tumor grade, histological subtype, incomplete resection and positive residual margins are strongly associated with PRT recurrence. Resection should be considered in patients with PRT for improving overall survival while prolonging RFS after resection.

[Bloodless medical and surgical procedures for retroperitoneal neoplasm resection].

OBJECTIVE: To investigate the Bloodless Medical and Surgical Procedures for retroperitoneal neoplasm resection. METHODS: Retrospectively analyse the Bloodless Medical and Surgical Procedures during 36 retroperitoneal neoplasm resections from Beijing Shijitan Hospital Affiliated to Capital Medical University from September 2009 to December 2010, to discuss the preoperative preparation, anesthetic induction and maintainance, intraoperative monitoring and use of vasoactive drugs related experience. RESULTS: All the patients were safe during the perioperative period, without any operative and anesthetic complication. By applying the Bloodless Medical and Surgical Procedures, the intraoperative haemodynamics maintained steady, the mean hematocrit decreased from 0.368 ± 0.095 before autologous blood collection to 0.252 ± 0.032 before the ends of operation. Majority of the patients (91.7%) stop using vasoactive drugs and extubated within 1 h after operation, and return wards. CONCLUSION: Erythrocyte-raising medicine therapy and modified preservation autologous blood transfusion are important process of Bloodless Medical and Surgical Procedures.

Epithelioid Inflammatory Myofibroblastic Sarcoma with Leukemoid Reaction.

Epithelioid inflammatory myofibroblastic sarcoma (EIMS) is a rare and aggressive inflammatory myofibroblastic tumour (IMT) variant. This report identifies the first case of EIMS with leukemoid reaction. This is also the first case in which pancreatic infiltration occurred from the disease onset. A 14-year male patient presented with an 18×18×10 cm mass at the retroperitoneal space and a white blood cell (WBC) count of 85×109/L. The mass and the invaded tissues were surgically removed with tumour-free margins. Histopathology and bone marrow aspiration confirmed the diagnosis of EIMS with leukemoid reaction. The tumour recurred with hepatic and pulmonary metastasis one month after the surgery. WBC count also increased progressively with the tumour recurrence. There is no consensus on the treatment of EIMS. Since ALK rearrangement presents in all the EIMS cases, surgical resection combined with crizotinib or other targeted drugs may improve the prognosis. Key Words: Sarcoma, Soft tissue neoplasms, Leukemoid reaction, Crizotinib.

A better overall survival (OS) for total (ipsilateral) retroperitoneal lipectomy than standard complete resection in patients with retroperitoneal liposarcoma: a comparative multi-institutional study.

Background: Complete resection (CR) serves as the standard of surgical treatment for retroperitoneal liposarcoma (RPLS). Unfortunately, even at referral centers, recurrence rates are high, and CR may not address multifocal diseases, which are a common phenomenon in RPLS. We sought to retrospectively compare the clinical outcomes of RPLS patients treated with total (ipsilateral) retroperitoneal lipectomy (TRL) and CR. Because TRL remove potentially multifocal tumors in the fat, patients may have a better prognosis than CR. Methods: Patients with primary/first-recurrent RPLS who had been treated at 5 referral centers were recruited from December 2014 to June 2018. Multivariable Cox regression analyses were conducted to determine the effects of demographic, operative, and clinicopathological variables on the following primary endpoints: local recurrence (LR), local recurrence-free survival (LRFS), and overall survival (OS). Results: A total of 134 patients were enrolled in this retrospective study, 53 of whom underwent TRL, and 81 of whom underwent CR. The 2 groups were comparable in terms of age, gender, presentation (primary vs. first-recurrent RPLS), number of tumors (unifocal vs. multifocal) at presentation, and Fédération Nationale des Centres de Lutte Contre le Cancer (FNCLCC) grade. The TRL group had higher levels of preoperative hemoglobin (Hb) (13 vs. 12.5 g/dL; P=0.008) and a lower amount of intraoperative blood loss (400 vs. 500 mL; P=0.034), but there were no significant differences in the length of hospital stay (23 vs. 22 d; P=0.47) or complications (32 vs. 30; P=0.82) between the 2 groups. In a subset of patients with multifocal tumors at initial presentation, OS was more prolonged in those treated with TRL than those treated with CR (P=0.0272). Based on the multivariable analysis, primary liposarcoma and a low FNCLCC grade were associated with decreased LR and improved OS. Conclusions: TRL is a safe procedure that positively affects the OS of patients with multifocal RPLS. This novel strategy deserves further investigation in prospective studies.

Utilizing multiple pathway cross-talk networks reveals hub pathways in primary mediastinal B-cell lymphoma.

OBJECTIVE: The objective of this paper was to reveal hub pathways in primary mediastinal B-cell lymphoma (PMBL) based on multiple pathway crosstalk networks (PCNs) and give insight for its pathological mechanism. MATERIALS AND METHODS: Based on gene expression data, pathway data and protein-protein interaction data, background PCN (BPCN) and tumor PCN (TPCN) of PMBL were constructed. The rank product algorithm was implemented to identify hub pathways of BPCN and TPCN. Finally, topological properties (degree, closeness, betweenness, and transitivity) of hub pathways were analyzed. RESULTS: For BPCN, there were three hundred nodes and 42,239 edges, and the pathway pairs had great overlaps. TPCN was composed of 281 nodes and 12,700 cross-talks. A total of five hub pathways were identified, nonalcoholic fatty liver disease (NAFLD), tuberculosis, human T-lymphotropic virus type-I (HTLV-I) infection, hepatitis B, and Epstein-Barr virus infection. The topological properties for them were different from each other, further between PMBL and normal controls. CONCLUSION: We have identified five hub pathways for PMBL, such as NAFLD, HTLV-I infection, and Hepatitis B, which might be potential biomarkers for target therapy for PMBL.

Tracking significant modules and key genes for esophageal squamous cell carcinoma based on differential modules.

BACKGROUND: The exact molecular mechanism of esophageal squamous cell carcinoma (ESCC) is still unknown, and the prognosis of ESCC has not been significantly improved. OBJECTIVE: To understand the molecular mechanism of ESCC, differential modules (DMs) and key genes were identified through conducting analysis on the differential co-expression network (DCN) based on the gene expression profiles of ESCC and protein-protein interaction (PPI) data. MATERIALS AND METHODS: First, gene expression profiles of ESCC and PPI data recruiting and preprocessing were conducted; then, a DCN was constructed based on the gene co-expression and gene differential expression in ESCC; in the following, candidate DMs were mined from DCN through a systemic module searching strategy, and significance analysis was performed on candidate DMs to identify DMs; moreover, significant genes contained in the DMs were analyzed to identify the underlying biomarkers for ESCC. Finally, pathway enrichment analysis was conducted to disclose the function of these DMs. RESULTS: A total of 10,975 genes were obtained after comprehensively preprocessing on the gene expression profiles and PPI data. Then, a DCN with 915 nodes (1164 interactions) was built, and 45 seed genes were identified. In the following, four DMs that separately enriched in phenylalanine metabolism, nicotine addiction, phenylalanine metabolism, and B-cell receptor signaling pathway were identified, where module 1 and module 3 were all enriched in phenylalanine metabolism pathway. Furthermore, the most significant seed gene myeloperoxidase (MPO) was contained in all of the DMs. CONCLUSIONS: In this study, we successfully identified 4 DMs, three significant pathways, and a key gene MPO in ESCC, which might play key roles during the occurrence and development of ESCC and could be chosen as good indicators and therapeutic schedule for ESCC.

Surgical management of retroperitoneal sarcoma and opportunities for global collaboration.

Retroperitoneal sarcomas (RPS) are rare cancers that often reach massive size before detection. The mainstay of treatment for RPS is surgical resection, and complete resection is the only chance for potential cure. The management of RPS can be challenging and in individual cases, radiation and systemic therapy may be beneficial in both primary and recurrent disease. Further research through multi-institutional collaboration, ideally on a global level, is needed to better understand RPS and optimize management of this disease.

Advanced colorectal adenoma related gene expression signature may predict prognostic for colorectal cancer patients with adenoma-carcinoma sequence.

BACKGROUND: There are still no absolute parameters predicting progression of adenoma into cancer. The present study aimed to characterize functional differences on the multistep carcinogenetic process from the adenoma-carcinoma sequence. METHODS: All samples were collected and mRNA expression profiling was performed by using Agilent Microarray high-throughput gene-chip technology. Then, the characteristics of mRNA expression profiles of adenoma-carcinoma sequence were described with bioinformatics software, and we analyzed the relationship between gene expression profiles of adenoma-adenocarcinoma sequence and clinical prognosis of colorectal cancer. RESULTS: The mRNA expressions of adenoma-carcinoma sequence were significantly different between high-grade intraepithelial neoplasia group and adenocarcinoma group. The biological process of gene ontology function enrichment analysis on differentially expressed genes between high-grade intraepithelial neoplasia group and adenocarcinoma group showed that genes enriched in the extracellular structure organization, skeletal system development, biological adhesion and itself regulated growth regulation, with the P value after FDR correction of less than 0.05. In addition, IPR-related protein mainly focused on the insulin-like growth factor binding proteins. CONCLUSION: The variable trends of gene expression profiles for adenoma-carcinoma sequence were mainly concentrated in high-grade intraepithelial neoplasia and adenocarcinoma. The differentially expressed genes are significantly correlated between high-grade intraepithelial neoplasia group and adenocarcinoma group. Bioinformatics analysis is an effective way to study the gene expression profiles in the adenoma-carcinoma sequence, and may provide an effective tool to involve colorectal cancer research strategy into colorectal adenoma or advanced adenoma.

[Surgery for extraperitoneal pelvic neoplasms].

OBJECTIVE: To evaluate the methods of surgery for extraperitoneal pelvic neoplasms. METHODS: Clinical data related to surgery of 84 cases of extraperitoneal pelvic neoplasms were extracted and retrospectively analyzed. RESULTS: All 84 patients underwent operations, including one of them who received 4 operations within 6 months for resection of a single tumor. 58 abdominal, 16 buttock and 10 combined incisions were made in the series. Pelvic organs and structures were co-resected in 35 cases, including total pelvic exenteration in 2 cases and anterior pelvic exenteration in 2 cases. Common and/or external iliac vessels were resected and transplantations of artificial vessel were carried in 5 cases. Internal iliac arteries were ligated in 10 cases. The mean blood lose was 2 385 ml in our series and the largest was 15 000 ml. The complete resection rate of tumor was 81% for 84 operations and the largest resected tumor was 30 cm x 30 cm x 25 cm. There was no hospitalized death, and postoperative complication rate was 7% (6/84) in our series. Only 1 death were seen during the mean period of postoperative follow-up of 54 months, 22 operations were carried for 21 cases of recurrence, including 7 operations for 7 recurrences in a case within 12 years. CONCLUSIONS: Making adequate abdominal or/and buttock incisions, exenterations of involved pelvic organs and structures, total pelvic exenteration if necessary, appropriate management of iliac vessels, planned re-operation for one tumor, and re-operation for recurrences are important methods for the treatment of extraperitoneal pelvic neoplasms.

Two Chinese pedigrees for adenomatous polyposis coli: new mutations at codon 1309 and predisposition to phenotypic variations.

Familial adenomatous polyposis (FAP) is an autosomal dominant inherited disease caused by a mutation in the adenomatous polyposis coli (APC) gene. Some studies have attempted to correlate mutations at codon 1309 with classic FAP (≥100 colorectal polyps). We report two Chinese FAP pedigrees with new frameshift mutations at codon 1309, in which affected individuals manifest phenotypic variations. Comprehensive physical examinations were performed for all living individuals and the medical data of deceased patients were collected. Screening of the APC and human mutY homolog (MUTYH) genes for germline mutations was conducted by direct polymerase chain reaction (PCR) sequencing. In two pedigrees, a heterozygous deletion in exon 16 of the APC gene was present in all FAP patients but absent in the unaffected individuals. There were no changes to the MUTYH gene. The first pedigree, with a new frameshift mutation at c.3926_3930 del AAAAG (p. Glu1309Aspfs X4), exhibited obvious differences in the polyp number such that the proband manifested only three colorectal polyps, whereas another patients showed the symptoms of classic FAP. The second pedigree, also traced a new mutation at c.3922_3925 del AAAG (p. Glu1309Argfs X11). Although all of the patients presented with classic polyposis, one of them exhibited a delayed onset of colorectal cancer in his 50s. Two novel mutations at codon 1309 in two Chinese families suffering from FAP could enrich the germline mutation spectrum of the APC gene. Families of individuals might manifest different phenotypes, even with an identical codon 1309 mutation, unlike in previous studies.

Salvage irrigation-suction in gracilis muscle repair of complex rectovaginal and rectourethral fistulas.

AIM: To evaluate the efficacy of gracilis muscle transposition and postoperative salvage irrigation-suction in the treatment of complex rectovaginal fistulas (RVFs) and rectourethral fistulas (RUFs). METHODS: Between May 2009 and March 2012, 11 female patients with complex RVFs and 8 male patients with RUFs were prospectively enrolled. Gracilis muscle transposition was undertaken in all patients and postoperative wound irrigation-suction was performed in patients with early leakage. Efficacy was assessed in terms of the success rate and surgical complications. SF-36 quality of life (QOL) scores and Wexner fecal incontinence scores were compared before and after surgery. RESULTS: The fistulas healed in 14 patients after gracilis muscle transposition; the initial healing rate was 73.7%. Postoperative leakage occurred and continuous irrigation-suction of wounds was undertaken in 5 patients: 4 healed and 1 failed, and postoperative fecal diversions were performed for the patient whose treatment failed. At a median follow-up of 17 mo, the overall healing rate was 94.7%. Postoperative complications occurred in 4 cases. Significant improvement was observed in the quality outcomes framework scores (P < 0.001) and Wexner fecal incontinence scores (P = 0.002) after the successful healing of complex RVFs or RUFs. There was no significant difference in SF-36 QOL scores between the initial healing group and irrigation-suction-assisted healing group. CONCLUSION: Gracilis muscle transposition and postoperative salvage wound irrigation-suction gained a high success rate in the treatment of complex RVFs and RUFs. QOL and fecal incontinence were significantly improved after the successful healing of RVFs and RUFs.

[Prospective study of gracilis muscle repair of complex rectovaginal fistula and rectourethral fistula].

OBJECTIVE: To assess the efficacy and experience of gracilis muscle transposition for complex rectovaginal fistula (RVF) and rectourethral fistula (RUF). METHODS: Nineteen patients underwent gracilis muscle transposition for complex RVF and RUF from May 2009 to November 2011 in the Beijing Shijitan Hospital and the clinical data were prospectively collected. The success rate and complications were recorded. SF-36 quality of life score, Wexner fecal incontinence score, and female sexual function score before surgery and 6 months after surgery were recorded. RESULTS: In 19 patients, there were 8 males (RUF) and 11 females (RUF). The times of failed attempt repair preoperatively ranged from 0-3 (mean, 1.0). The diameter of the fistula ranged from 0.5-3.0 cm (mean, 1.6), and all fistulas located above the sphincter. The operative time ranged from 145-400 minutes (median, 240). The postoperative hospital stay ranged from 10-39 days (median 21). Early postoperative complications included thigh pain and numbness in 2 cases, leg numbness in 2 cases. No long-term complications were noticed. The follow-up period ranged from 6-35 months (median, 18). The gracilis muscle transposition had a healing rate of 94.7% (18/19). As compared with the preoperative level, Wexner score decreased from 10.0±8.8 to 2.9±5.8, and the continence function improved significantly (P=0.002). Sexual function score of 11 female patients increased from 1.0±1.8 to 4.0±4.0, and the sexual function had a significant improvement after surgery (P=0.022). SF-36 quality of life scores improved significantly (P<0.001). CONCLUSIONS: Gracilis muscle transposition for complex rectovaginal fistula and rectourethral fistula has high success rate with mild and rare complications.

[Comparison of clinical manifestation and severity between hospital-based American and Chinese patients with colorectal Crohn disease].

OBJECTIVE: To evaluate the differences in clinicopathological characteristics and severity between American and Chinese patients with colorectal Crohn disease(CD). METHODS: Between March 1985 and September 2004, 68 patients with colorectal CD in Cleveland Clinic Florida (America) and 85 patients with colorectal CD in the 301 Hospital(China) were enrolled in the study. Data of two groups,including demographics, clinical characteristics, extraintestinal manifestations, presenting symptoms, location and pathological characteristics,were compared. RESULTS: 60.3% of American patients and 36.5% of Chinese patients were female(P=0.003). 11.8% of American patients and 1.2% of Chinese patients had a family history of CD(P=0.016). American patients had a significantly higher rate of extraintestinal disease (39.7% vs 20.0%), abscess(19.0% vs 0), and anorectal fistulas(51.5% vs 0). American patients had significantly more extensive disease than Chinese patients(pancolitis: 44.1% vs 4.7%, P<0.01). American patients had a significantly higher rate of disease involving the ascending colon, transverse colon, descending colon, sigmoid colon, anorectal area compared with Chinese patients(all P<0.05). CONCLUSIONS: American patients with colorectal Crohn disease seem to have a female predominance, a higher rate of CD family history, to involve the distal intestinal tract more often, and have more severe clinical manifestation and pathological process, as compared with Chinese patients.