Self-expandable metallic stent as a bridge to elective surgery versus emergency surgery for acute malignant colorectal obstruction.

BACKGROUD: The efficacy and safety of self-expandable metallic stents (SEMSs) as a bridge for patients with acute malignant colorectal obstructions (AMCOs) are still controversial. We conducted this study to evaluate the outcomes of patients with AMCOs treated by different strategies. METHODS: From January 2010 to March 2014, a total of 171 patients with AMCOs from Zhongshan Hospital were retrospectively enrolled in this study. One hundred twenty patients successfully received stent placement followed by one-stage laparoscopic or open resection in the stent group, and 51 patients received emergency operations in the emergency group. RESULTS: The operation duration and postoperative hospital stay were significantly shorter in the stent group (114.51 ± 28.65 vs. 160.39 ± 58.94 min, P < 0.001; 8.00 ± 3.97 vs. 12.59 ± 9.07 days, P = 0.001). The stent group also had significantly reduced intraoperative blood loss and the incidence of postoperative complications compared with the emergency group (61.00 ± 43.70 vs. 121.18 ± 85.90 ml, P < 0.001; 16.7 vs. 37.3%, P = 0.003). Kaplan-Meier survival curves showed that the median survival time in the stent group was significantly longer than that in the emergency group (53 vs. 41 months, P = 0.034). In subgroup analysis of stent group, the stent laparoscopy group had significantly decreased postoperative complications (P = 0.025), and similar long-term survival (P = 0.81). CONCLUSIONS: Stent placement as a bridge to surgery is a safe and feasible procedure and provides significant advantages in terms of short-term outcomes and favorable prognoses for patients with AMCOs. Laparoscopic surgery could be considered as an optimal treatment after stent placement.

Aberrant expression of long noncoding RNAs in colorectal cancer with liver metastasis.

Long noncoding RNA (lncRNA) plays a crucial role in the regulation of various cellular processes and human diseases. However, little is known about the role of lncRNAs in colorectal liver metastasis (CLM). In the present study, we aimed to determine whether lncRNAs are differentially expressed in CLM tissue and to further assess their clinical value. lncRNA arrays were employed to screen for differentially expressed lncRNAs in colorectal cancer (CRC) tissues with synchronous, metachronous, or nonliver metastasis. Based on bioinformatics data, a quantitative reverse-transcription polymerase chain reaction (qRT-PCR) assay was performed to identify target lncRNAs in an expanded set of CRC samples with various subtypes of liver metastasis. The relationships between the target lncRNAs and the clinical characteristics and patient prognosis were further analyzed. After determining the expression profile of lncRNAs (n = 1332) in CLM tissue, 40 differentially expressed lncRNAs that were potentially related to CLM were selected for further examination in an expanded set of clinical samples, and three novel target lncRNAs, termed lncRNA-CLMAT1-3, were verified. High lncRNA-CLMAT3 expression strongly correlated with liver metastasis (P = 0.03) and lymph node metastasis (P = 0.009). Moreover, patients displaying high lncRNA-CLMAT3 expression exhibited a shorter median overall survival duration than those displaying low lncRNA-CLMAT3 expression (30.7 vs. 35.2 months, P = 0.007). Multivariate analysis demonstrated that the lncRNA-CLMAT3 expression level is an independent prognostic factor (hazard ratio 2.05, P = 0.02) after adjusting for other known prognostic factors. lncRNA-CLMAT3 over-expression was significantly associated with CLM and was an independent predictor of poor survival for patients with CRC.

General anesthesia combined with epidural anesthesia ameliorates the effect of fast-track surgery by mitigating immunosuppression and facilitating intestinal functional recovery in colon cancer patients.

PURPOSE: The purpose of this study is to investigate the influence of anesthetic methods on markers of anti-tumor immunity and intestinal functions in fast-track surgery in colon cancer (CC) patients during the perioperative period. PATIENTS AND METHODS: A total of 53 patients with American Society of Anesthesiologists (ASA) I-II status randomly received general anesthesia (G group, n = 27) or general anesthesia combined with epidural anesthesia (E group, n = 26) for surgical tumor resection. The recovery times of intestinal function were evaluated in both groups postoperatively. The frequencies of different subsets of CD4+ T cells and myeloid-derived suppressor cells and C-reactive protein (CRP) were measured by flow cytometry and enzyme-linked immunosorbent assay, respectively, before anesthesia (t0), 1 h after the beginning of surgery (t1), 1 h after the end of surgery (t2), and on day 2 (t3) and day 5 (t4) post-surgery. RESULTS: There was no significant difference in demographic characteristics between the two groups, but the E group of patients received significantly lower amounts of morphine and sevoflurane. In comparison with those in the G group, significantly greater numbers of lymphocytes and elevated frequencies of Th1 cells were detected at t3 and t4 post-surgery in the E group (p < 0.01). Significantly lower percentages of Th2 cells and regulatory T cells were detected in the E group at t2-4 post-surgery. Whereas the levels of plasma CRP increased post-surgery in both groups, the levels of CRP were significantly lower in the E group than those in the G group at t3-4 post-surgery (p < 0.05). The times to the first flatus and to tolerate a full diet were significantly shorter in the E group than those in the G group (p < 0.01). CONCLUSION: General anesthesia combined with epidural anesthesia plays an important role in fast-track surgery, mitigating the surgical stress-related impairment of anti-tumor immune responses and hastening the recovery of intestinal function. This combination might also help to improve long-term outcomes for CC patients.

Impact of early tumor shrinkage on clinical outcome in wild-type-KRAS colorectal liver metastases treated with cetuximab.

BACKGROUND AND AIM: To evaluate the impact of early tumor shrinkage (ETS) on long-term outcome in patients with wild-type Kirsten rat sarcoma viral oncogene homolog (KRAS) unresectable colorectal liver metastases (CLM) receiving cetuximab plus chemotherapy. METHODS: A total of 138 patients in a randomized controlled trial (70 in armA received cetuximab plus chemotherapy, 68 in armB received chemotherapy alone), as previously reported (Ye et al., 2013) were included into this analysis. The cut-off date updated for overall survival (OS) was June 2014. ETS was defined as a ≥ 20% reduction of the longest diameters of the target lesions compared with baseline at the first evaluation (8 weeks). Outcome measures were progression-free survival (PFS) and OS. RESULTS: There were 132 patients available for evaluation, and ETS occurred more frequently in armA than that in armB (P = 0.003). ETS was associated with longer OS (armA: 35.7 vs. 19.5 months, P < 0.001; armB 28.7 vs. 18.7 months, P = 0.01) and PFS (armA: 13.4 vs. 4.2 months, P < 0.001; armB 7.0 vs. 4.2 months, P = 0.001) compared with patients with no-ETS. Among patients with ETS, there was a significant difference between armA and armB in PFS (P = 0.03), but not in OS (P = 0.19). All 23 patients who underwent liver surgery achieved ETS. In armA, for patients without liver surgery, patients observed ETS also gained an increased survival benefit over those no-ETS in OS (P = 0.02) and PFS (P < 0.001). ETS was an independent predictor of improved OS (hazard ratio 0.56, P = 0.007). CONCLUSION: ETS may serve as a predictor of favorable outcome in patients with wild-type KRAS CLM receiving cetuximab plus chemotherapy.

Colorectal liver metastases: Correlations of contrast-enhanced ultrasound features with tumor clinicopathological factors and clinical outcomes following conversion therapy.

OBJECTIVE: To explore the prognostic impact of contrast-enhanced ultrasound (CEUS) features for initially unresectable colorectal liver metastases (CLMs) in a clinical setting of conversion therapy. METHODS: Between March 2015 and November 2020, consecutive patients with CLMs who received conversion treatment were prospectively enrolled. All participants underwent liver CEUS at baseline. The primary endpoint was conversion resection rate (R0 and overall resection). Secondary endpoints were objective response rate (ORR), overall survival (OS), and progression-free survival (PFS). RESULTS: 104 participants who completed conversion treatment were included. CEUS enhancement pattern was correlated with index lesion (size and echogenicity), primary (site, differentiation, perineural invasion, and RAS genotype) and serum (CA19-9 level) characteristics (P = <0.001-0.016). CEUS enhancement pattern was significantly associated with R0 resection rate, ORR, PFS, and OS (P = 0.001-0.049), whereas enhancement degree was associated with PFS and OS (P = 0.043 and 0.045). Multivariate analysis showed that heterogeneous enhancement independently predicted R0 and overall resection (P = 0.028 and 0.024) while rim-like enhancement independently predicted ORR and OS (P = 0.009 and 0.026). CONCLUSION: CEUS enhancement pattern was significantly associated with tumor characteristics and clinical outcomes following conversion therapy, and thus might be of prognosis impact for initially unresectable CLMs.

High patatin like phospholipase domain containing 8 expression as a biomarker for poor prognosis of colorectal cancer.

BACKGROUND: Patatin like phospholipase domain containing 8 (PNPLA8) has been shown to play a significant role in various cancer entities. Previous studies have focused on its roles as an antioxidant and in lipid peroxidation. However, the role of PNPLA8 in colorectal cancer (CRC) progression is unclear. AIM: To explore the prognostic effects of PNPLA8 expression in CRC. METHODS: A retrospective cohort containing 751 consecutive CRC patients was enrolled. PNPLA8 expression in tumor samples was evaluated by immunohistochemistry staining and semi-quantitated with immunoreactive scores. CRC patients were divided into high and low PNPLA8 expression groups based on the cut-off values, which were calculated by X-tile software. The prognostic value of PNPLA8 was identified using univariate and multivariate Cox regression analysis. The overall survival (OS) rates of CRC patients in the study cohort were compared with Kaplan-Meier analysis and Log-rank test. RESULTS: PNPLA8 expression was significantly associated with distant metastases in our cohort (P = 0.048). CRC patients with high PNPLA8 expression indicated poor OS (median OS = 35.3, P = 0.005). CRC patients with a higher PNPLA8 expression at either stage I and II or stage III and IV had statistically significant shorter OS. For patients with left-sided colon and rectal cancer, the survival curves of two PNPLA8-expression groups showed statistically significant differences. Multivariate analysis also confirmed that high PNPLA8 expression was an independent prognostic factor for overall survival (hazard ratio HR = 1.328, 95%CI: 1.016-1.734, P = 0.038). CONCLUSION: PNPLA8 is a novel independent prognostic factor for CRC. These findings suggest that PNPLA8 is a potential target in clinical CRC management.

Unveiling major histocompatibility complex-mediated pan-cancer immune features by integrated single-cell and bulk RNA sequencing.

Immune checkpoint inhibitors (ICIs) have transformed cancer therapy, yet persistent challenges such as low response rate and significant heterogeneity necessitate attention. The pivotal role of the major histocompatibility complex (MHC) in ICI efficacy, its intricate impacts and potentials as a prognostic marker, warrants comprehensive exploration. This study integrates single-cell RNA sequencing (scRNA-seq), bulk RNA-seq, and spatial transcriptomic analyses to unveil pan-cancer immune characteristics governed by the MHC transcriptional feature (MHC.sig). Developed through scRNA-seq analysis of 663,760 cells across diverse cohorts and validated in 30 solid cancer types, the MHC.sig demonstrates a robust correlation between immune-related genes and infiltrating immune cells, highlighting its potential as a universal pan-cancer marker for anti-tumor immunity. Screening the MHC.sig for therapeutic targets using CRISPR data identifies potential genes for immune therapy synergy and validates its predictive efficacy for ICIs responsiveness across diverse datasets and cancer types. Finally, analysis of cellular communication patterns reveals interactions between C1QC+macrophages and malignant cells, providing insights into potential therapeutic agents and their sensitivity characteristics. This comprehensive analysis positions the MHC.sig as a promising marker for predicting immune therapy outcomes and guiding combinatorial therapeutic strategies.

Coiled-coil domain-containing 154 promotes colorectal cancer proliferation and metastasis via interacting with minichromosome maintenance complex component 2.

Coiled-Coil Domain-Containing (CCDC) is a large class of structural proteins containing left-handed supercoiled structure. The clinical value and the functional implication of CCDC in colorectal cancer (CRC) remain unknown. Based on the genetic, transcriptional, and clinical data from The Cancer Genome Atlas, five of thirty-six CCDC proteins were differentially expressed in the CRC and associated with the survival of patients with CRC. A CCDC-score model was established to evaluate the prognosis of patients. The potential function of Coiled-Coil Domain-Containing 154 (CCDC154) was investigated using bioinformatical methods, which unveiled that high expression of CCDC154 indicates poor survival for patients with CRC and correlates with low infiltration of CD8+ T cells and high infiltration of neutrophils, indicating that CCDC154 enhances tumor growth and metastasis. CCDC154 interacts with Minichromosome Maintenance Complex Component 2 (MCM2) protein and promotes malignant phenotype via MCM2. We validated the expression level and survival prediction value of CCDC154 in clinical samples, and analyzed its co-expression of MCM2, Ki-67 and p53. This work discloses the role of CCDC in clinical setting and CCDC154 functions in CRC.

Low ferroptosis score predicts chemotherapy responsiveness and immune-activation in colorectal cancer.

BACKGROUND: Existing studies for ferroptosis and prognosis in colorectal cancer (CRC) were limited. In this study, we aim to investigate the prognostic role of ferroptosis markers in patients with CRC and exploration of its micro-environmental distributions. METHODS: Immunohistochemical staining was performed for CRC patients' tissue microarray. Selection and prognostic validation of markers were based on mRNA data from the cancer genome atlas (TCGA) database. Gene Set Enrichment Analysis (GSEA) was performed to indicate relative immune landmarks and hallmarks. Ferroptosis and immune contexture were examined by CIBERSORT. Survival outcomes were analyzed by Kaplan-Meier analysis and cox analysis. RESULTS: A panel of 42 genes was selected. Through mRNA expression difference and prognosis analysis, GPX4, NOX1 and ACSL4 were selected as candidate markers. By IHC, increased GPX4, decreased NOX1 and decreased FACL4 indicate poor prognosis and worse clinical characteristics. Ferroptosis score based on GPX4, NOX1 and ACSL4 was constructed and validated with high C-index. Low ferroptosis score can also demonstrate the better progression free survival and better adjuvant chemotherapy (ACT) responsiveness. Moreover, tumor with low ferroptosis score tend to be infiltrated with more CD4+ T cells, CD8+ T cells and less M1 macrophage. Finally, we found that IFN-γ was potentially the central molecule at the crossroad between ferroptosis and onco-immune response. CONCLUSION: Ferroptosis plays important role on CRC tumor progression, ACT response and prognosis. Ferroptosis contributes to immune-supportive responses and IFN-γ was the central molecule for this process.

[A study of sympathetic skin response to the damage of autonomic nerves function in patients with chronic N-hexane poisoning].

OBJECTIVE: To study the sympathetic skin response (SSR) to the effects of N-hexane on autonomic nerves function in patients with chronic N-hexane poisoning. METHODS: The subjects in present study included 30 controls and 37 cases with chronic N-hexane poisoning. Also 37 patients were divided into 3 subgroups (mild, moderate and severe poisoning) according to diagnostic criteria of occupational diseases. All subjects were examined by SSR test and nerve conduction velocity (NCV) test. All patients were reexamined by SSR and NCV every 1 ∼ 2 months. The differences in SSR parameters (latency, amplitude) among groups were observed. In the severe poisoning subgroup, the changes of SSR and NCV parameters (conduction velocity, amplitude) in different poisoning stages were observed. RESULTS: There were significant differences in SSR latency of upper extremity among groups and the significant differences in SSR amplitude of upper and lower extremity among groups (P < 0.05). No significant differences in SSR parameters were found between the adjacent groups (P > 0.05). There were significant differences in SSR latency of upper extremity during different periods and the significant differences in SSR amplitude of upper and lower extremity during different periods among all groups (P < 0.05). The change of SSR parameters consistent with that in NCV. The longest SSR latency of upper extremity and the smallest SSR amplitudes of upper and lower extremity appears 1 - 2 months earlier than that of the smallest action potential amplitude. CONCLUSION: The damage of autonomic nerves induced by N-hexane increased with poisoning progresses. The damage of autonomic nerves corresponded with the damage of myelin sheath of large myelinated nerves, but which appeared 1 - 2 months earlier than the damage of axon of large myelinated nerves. SSR test may serve as a method to detect the damage of autonomic nerves function in patients with chronic N-hexane poisoning.

Combined test of third lumbar skeletal muscle index and prognostic nutrition index improve prognosis prediction power in resected colorectal cancer liver metastasis.

BACKGROUND: In this paper, we aim to explore clinical value of skeletal muscle index (SMI) and prognostic nutrition index (PNI) on resected colorectal cancer liver metastasis (CRLM). RESULTS: Among the 539 patients, 355 were males. Baseline lower SMI was associated with smaller BMI, smaller PNI, smaller pre-albumin and longer hospitalization days (P<0.05). Patients with lower SMI and PNI had significantly shorter duration of PFS and OS (P<0.05). SMI can reflect the postoperative treatment response. Postoperative 6-month's and 12-month's SMI and PNI can indicate overall prognosis. When combined SMI and PNI, prognostic AUC of ROC curves improved significantly. CONCLUSION: Combined monitor of SMI and PNI can improve the power at predicting prognosis. Postoperative 6-month's record of SMI and PNI was more accurate and predictive for CRLM prognosis. METHOD: A total of 539 resected CRLM patients between January 2013 to December 2016 with complete clinical data were included. Computed tomography image was collected from each patient. Receiver-operating characteristic (ROC) curves were constructed; area under curves (AUC) were also determined. All clinical variables were analyzed in proper way.

[Application of SELDI-TOF-MS in detection of liver metastasis from colorectal cancer].

OBJECTIVE: To establish a serum protein fingerprint model for prediction of liver metastasis from colorectal cancer by SELDI-TOF-MS analysis, and to determine the differentiatial proteins associated with the metastatic liver cancers. METHODS: Data were collected from the Department of General Surgery in Zhongshan Hospital. A group of patients with colorectal cancer (CRC) without liver metastasis (n = 36) and another group with liver metastasis (n = 36) were included in this study. Serum samples were collected from peripheral venous blood before operation. Special serum protein or peptide fingerprint was determined by surface-enhanced laser desorption/ionization time-of-flight mass spectrometry (SELDI-TOF-MS). The obtained data were analyzed by Biomarker Wizard software to screen the serum protein markers discriminating colorectal cancer patients with and without liver metastasis. A serum protein fingerprint model was established. This model was blindly verified in of CRC patients with and 44 cases without liver metastasis. RESULTS: Comparing the characteristic proteins in those two groups of patients, 10 specific protein peaks were identified with statistical significance (P < 0.05). According to m/z growing from small to large, they were: 2398, 2814, 4084, 4289, 4465, 6422, 6619, 11 482, 11 649 and 13 714. The predictive model had a sensitivity of 91.7% and a specificity of 97.2%. The validation showed a sensitivity of 75.0% and a specificity of 81.8%. CONCLUSION: A predictive model based on differentiatial serum protein fingerprint with high sensitivity and specificity has been successfully established. It should be a very useful tool in detection and diagnosis of liver metastasis in colorectal cancer patients.

[Establish predictive model of colorectal cancer by using surface enhanced laser desorption/ionization-time of flight-mass spectrometry].

OBJECTIVE: To establish serum proteome fingerprinting predictive models and search for proteins associated with colorectal cancer. METHODS: Thirty-six randomly selected colorectal cancer patients and 36 cases with hernia or gall bladder diseases scheduled for elective operation were enrolled as cancer group and control group respectively. Peripheral venous blood samples were collected before the operations. Special serum protein or peptide fingerprint was investigated by using surface enhanced laser desorption/ ionization-time of flight-mass spectrometry (SELDI-TOF-MS) measurement after blood sample had been treated with weak cation exchange protein chip (CM10) for each case. The obtained data were analyzed by Biomarker Wizard software to screen serum proteome tumor markers and set up diagnosis predictive model for colorectal cancer. Blind validation of the model with 44 healthy controls and 88 colorectal cancer patients were carried out by using Biomarker Patterns Software. RESULTS: In comparing colorectal cancer group with control group, 5 specific protein peaks (P < 0.05) were found. The predictive model had a sensitivity of 100% and a specificity of 97.2%. A sensitivity of 71.6% and a specificity of 72.7% was got with the blind validation. The specific protein peaks with a mass-to-charge ratio (m/z) of 8908 and 13,707 showed in all the results and it showed their strong relationship with colorectal cancer. CONCLUSIONS: The predictive models built by the differences of serum proteome fingerprint could be a very useful diagnostic tool in colorectal cancer. Proteins with m/z of 8908 and 13,707 would possibly be the tumor markers of colorectal cancer.

[Therapeutic effects of hepatic resection in liver metastasis of colorectal cancer].

OBJECTIVES: To evaluate therapeutic effects of hepatic resection in liver metastasis of colorectal cancer (LMCC). METHODS: The clinical data of 133 cases of LMCC received hepatic resection from January 1, 2000 to December 31, 2005 in Zhongshan Hospital were analyzed retrospectively. The relationship between hepatic resection and survival rate was also concerned. RESULTS: One hundred and thirty-three cases received curative hepatic resection in all 470 LMCC cases, of which 30 cases from synchronous liver metastasis (SLM) group (totaled 196 cases) and 103 cases from metachronous liver metastasis (MLM) group (totaled 274 cases). Mortality rate during operation was 3.3% in SLM and 1.9% in MLM (P < 0.05). All patients were followed-up till June 31, 2006, the 1, 3, 5 year survival rates and median survival time of SLM were similar to those of MLM, but its recurrence rate was higher (36.7% vs 20.4%, P = 0.030). The 1, 3, 5 year survival rate in the 49 patients who were operable but received non-operation treatment were significantly lower than those in operated patients (P = 0.003). In 30 SLM cases, 22 received I stage resection of their primary and liver metastasis tumor and 8 received liver metastasis resection after the primary surgery (II stage operation), 1, 2, 3 year survival and the median survival time were similar in the two groups. With COX multivariate analysis, incision margin > or = 1 cm (P = 0.036) and reoperation after recurrence (P = 0.041) were protective survival factors, and post-operation recurrence (P = 0.023) was survival risk factor. CONCLUSIONS: Curative hepatic resection is the first choice of therapy in liver metastasis of colorectal cancer and it can improve survival.

Downregulated long non-coding RNA CLMAT3 promotes the proliferation of colorectal cancer cells by targeting regulators of the cell cycle pathway.

Over-expression of long non-coding RNA (lncRNA)-CLMAT3 is significantly associated with colorectal liver metastasis and is an independent predictor of poor survival for colorectal cancer patients. However, as little is known regarding the role of this gene in the proliferation of colorectal cancer in vitro, we investigated the involvement of lncRNA-CLMAT3 in colorectal cancer cell proliferation. In this study, we demonstrate that lncRNA-CLMAT3 expression was significantly increased in colorectal cancer cells compared with a normal intestinal mucous cell line and that inhibition of lncRNA-CLMAT3 suppressed colorectal cancer cell proliferation in vitro. We also found that this reduced colorectal cancer cell proliferation due to lncRNA-CLMAT3 knockdown is associated with G0/G1 cell-cycle arrest induction and apoptosis enhancement. Furthermore, lncRNA-CLMAT3 knockdown enhanced Cdh1 expression and resulted in p27Kip accumulation via increased Skp2 protein ubiquitination. Taken together, our findings suggest that reducing lncRNA-CLMAT3 inhibits colorectal cancer cell proliferation by affecting cell cycle components.

Involvement of long non-coding RNA in colorectal cancer: From benchtop to bedside (Review).

Colorectal cancer (CRC) is one of the greatest threats to public health. Recent advances in whole-genome transcriptome analyses have enabled the identification of numerous members of a novel class of non-coding (nc)RNA, long ncRNA (lncRNA), which is broadly defined as RNA molecules that are >200 nt in length and lacking an open reading frame. In the present review, all lncRNAs associated with CRC are briefly summarized, with a particular focus on their potential roles as clinical biomarkers. CRC-associated lncRNAs involved in the underlying mechanisms of CRC progression are also initially included. This should benefit the development of novel markers and effective therapeutic targets for patients with CRC.

Anti-EGFR and anti-VEGF agents: important targeted therapies of colorectal liver metastases.

Colorectal liver metastasis (CLM) is common worldwide. Targeted therapies with monoclonal antibodies have been proven effective in numerous clinical trials, and are now becoming standards for patients with CLM. The development and application of anti-epidermal growth factor receptor (anti-EGFR) and anti-vascular endothelial growth factor (anti-VEGF) antibodies represents significant advances in the treatment of this disease. However, new findings continue to emerge casting doubt on the efficacy of this approach. The Kirsten rat sarcoma viral oncogene (KRAS) has been proven to be a crucial predictor of the success of anti-EGFR treatment in CLM. Whereas a recent study summarized several randomized controlled trials, and showed that patients with the KRAS G13D mutation significantly benefited from the addition of cetuximab in terms of progress-free survival (PFS, 4.0 mo vs 1.9 mo, HR = 0.51, P = 0.004) and overall survival (OS, 7.6 mo vs 5.7 mo, HR = 0.50, P = 0.005). Some other studies also reported that the KRAS G13D mutation might not be absolutely predictive of non-responsiveness to anti-EGFR therapy. At the same time, "new" RAS mutations, including mutations in neuroblastoma RAS viral (v-ras) oncogene homolog (NRAS) and exons 3 and 4 of KRAS, have been suggested to be predictors of a poor treatment response. This finding was first reported by the update of the PRIME trial. The update showed that for patients with non-mutated KRAS exon 2 but other RAS mutations, panitumumab-fluorouracil, leucovorin, and oxaliplatin (FOLFOX)4 treatment led to inferior PFS (HR = 1.28, 95%CI: 0.79-2.07) and OS (HR = 1.29, 95%CI: 0.79-2.10), which was consistent with the findings in patients with KRAS mutations in exon 2. Then, the update of the PEAK trial and the FIRE-III trial also supported this finding, which would reduce candidates for anti-EGFR therapy but enhance the efficacy. In first-line targeted combination therapy, the regimens of cetuximab plus FOLFOX was called into question because of the inferior prognosis in the COIN trial and the NORDIC-VII trial. Also, bevacizumab plus oxaliplatin-based chemotherapy was questioned because of the NO16966 trial. By the update and further analysis of the COIN trial and the NORDIC-VII trial, cetuximab plus FOLFOX was reported to be reliable again. But bevacizumab plus oxaliplatin-based chemotherapy was still controversial. In addition, some trials have reported that bevacizumab is not suitable for conversion therapy. The results of the FIRE-III trial showed that cetuximab led to a significant advantage over bevacizumab in response rate (72% vs 63%, P = 0.017) for evaluable population. With the balanced allocation of second-line treatment, the FIRE-III trial was expected to provide evidence for selecting following regimens after first-line progression. There is still no strong evidence for the efficacy of targeted therapy as a preoperative treatment for resectable CLM or postoperative treatment for resected CLM, although the combined regimen is often administered based on experience. Combination therapy with more than one targeted agent has been proven to provide no benefit, and even was reported to be harmful as first-line treatment by four large clinical trials. However, recent studies reported positive results of erlotinib plus bevacizumab for maintenance treatment. The mechanism of antagonism between different targeted agents deserves further study, and may also provide greater understanding of the development of resistance to targeted agents.

Primary colonic melanoma presenting as ileocecal intussusception: case report and literature review.

Primary malignant melanoma originating in the colon is an extremely rare disease. Herein, we report a case of primary melanoma of the ascending colon. The patient was a 57-year-old male who was admitted to our hospital for persistent abdominal pain and episodes of bloody stool, nausea and vomiting. A computed tomography scan revealed lower intestinal intussusception and enlarged lymph nodes in the abdominal cavity and retroperitoneum. During laparoscopic operation, multiple enlarged lymph nodes were found. Several segments of the proximal small intestine were incarcerated into the distal small intestine, forming an internal hernia and obstruction. The necrotic terminal ileum was invaginated into the ascending cecum. Subsequently, adhesive internal hernia reduction and palliative right hemicolectomy were performed. Pathologic examination of the excised specimen revealed a polypoid mass in the ascending colon. Histological examination showed epithelioid and spindle tumor cells with obvious cytoplasmic melanin deposition. Immunohistochemical staining revealed that the tumor cells were positive for S-100, HMB-45 and vimentin, confirming the diagnosis of melanoma. The patient history and a thorough postoperative investigation excluded the preexistence or coexistence of a primary lesion elsewhere in the skin, anus or oculus or at other sites. Thus, we consider our case to represent an aggressive primary colon melanoma presenting as ileocecal intussusception and intestinal obstruction.

[Consideration of therapy for colorectal cancer with synchronous unresectable liver metastasis].

A variety of managements, including systemic and local chemotherapy, radiofrequency ablation and others, are used after multidisciplinary team discussion to improve the survival of patients with unresectable liver metastasis, and to enlarge the cohort of patients who can be managed with curative intent. Patients should be divided into different clinical groups according to characteristics of the patient and tumor, and then receive different treatments. For the patients who may be converted to be resectable after chemotherapy, we should choose efficient convertible chemotherapy with short courses to get the best response rate. For KRAS wild-type patients, cetuximab combined with FOLFOX/FOLFIRI, in which 5-fluorouracil is continuously infused, is recommended. In addition, resection of the primary tumor is recommended at the right time for asymptomatic patients with unresectable liver metastases. There is no consensus on the preferred treatment modality for systemic and local therapies.