Surgery In Colon Cancer Patients Research Articles

Safety and Efficacy Analysis of Radical Surgery for 403 Patients with Colon Cancer over 80 Years Old.

Aim: To investigate the safety and efficacy of radical surgery in colon cancer patients over 80 years old. Methods: Data from colon cancer patients aged ≥80 years who underwent radical surgery at the Cancer Hospital of the Chinese Academy of Medical Sciences and affiliated Heji Hospital of Changzhi Medical College from January 2011 to December 2022 were retrospectively analysed. Data on clinical characteristics, pathological features, perioperative data, and long-term prognosis were collected. Severe complications were classified as grade III-V. Logistic regression models were used to identify the risk factors for severe postoperative complications, and a Cox regression model was used to determine prognostic variables. Results: A total of 403 eligible patients were included in the study. A total of 118 (29.3%) patients developed postoperative complications, of which 51 (12.7%) experienced grade 3-5 severe complications. Two (0.5%) patients died of pulmonary embolism and myocardial infarction during the perioperative period. The multivariate logistic regression analysis showed that preoperative albumin levels <35 g/L and right colon cancer were independent risk factors for grade 3-5 postoperative complications. In terms of prognosis, multivariate analysis revealed that overall survival was significantly affected by TNM stage III and grade 3-4 postoperative complications. In addition, TNM stage III and perineural invasion were the independent prognostic factors for disease-free survival. Conclusion: Radical surgery can be performed safely in elderly colon cancer patients aged over 80 years, with an acceptable morbidity and mortality. Patients with preoperative albumin levels <35 g/L or tumors in the right colon should be alerted to the development of severe postoperative complications. In addition, the occurrence of severe complications can significantly affect the prognosis of elderly colon cancer patients.

A Comparison between Open and Minimally Invasive Right Hemicolectomies in Patients with Locally Advanced UICC Stage III Colon Cancer: A Protocol for a Systematic Review and an Individual Patient Data Meta-Analysis

Despite the development of new technologies and multimodal therapies, improving the prognosis of patients with UICC stage III right colon adenocarcinoma remains challenging. Several randomized controlled trials have shown the oncological non-inferiority of minimally invasive surgery compared to open surgery for colon cancer patients. However, for UICC stage III patients, carrying the highest risk for local recurrence and the worst survival, the evidence remains inconclusive. The aim of this systematic review and individual patient data meta-analysis is to improve the scarce evidence regarding minimally invasive surgery for this subgroup of patients. Data from adult patients with pathologically UICC stage III right adenocarcinoma of the colon will be included. The intervention to be assessed is the minimally invasive right hemicolectomy in comparison with the open procedure. The primary outcome will be the 5-year overall survival. Secondary outcomes will include further long-term outcomes, such as disease-free survival, short term, and histological outcomes. Only randomized controlled trials and quasi-randomized controlled clinical trials will be included. The literature search will be conducted in the following databases: PubMed, CINAHL, Cochrane Trials, ClinicalTrials.gov, and Web of Science. The review will be performed using the Cochrane methodology including GRADE tools. The findings of this meta-analysis will be important for choosing optimal treatment pathways and tailoring of surgical therapy in patients with locally advanced UICC stage III right colon cancer.

Safety and feasibility of robotic surgery for colon cancer patients with previous abdominal surgery: a propensity score-matching analysis.

Robotic surgery is widely used in gastrointestinal surgery. While the application of robotic surgery for colon cancer patients with previous abdominal surgery (PAS) remains controversial for the fear of intra-abdominal adhesions. This study was aimed to evaluate the safety and feasibility of robotic colectomy for patients with PAS. The medical records of colon cancer patients who underwent robotic surgery at our hospital from June 2015 to August 2020 were extracted and analyzed. Propensity score-matching (PSM) analysis was implemented to minimize selection bias. We compared perioperative outcomes and postoperative complications between the patients with PAS or with no PAS (NPAS). A total of 79 patients (PAS group) and 348 patients (NPAS group) were included in our study. After PSM, 79 patients of PAS group and 79 patients of NPAS group were selected for further analysis. We did not find statistical difference in operative time, estimated blood loss, lymph nodes retrieved, length of hospital stay and hospital costs between the two groups. No difference was noted in the incidence of postoperative complications, conversion to open surgery and mortality between the two groups. According to the results of multivariate analysis, PAS was not identified as risk factor for postoperative complications. Left hemicolectomy and perioperative transfusion were associated with postoperative complications. PAS did not negatively affect the outcomes of robotic colectomy. After individually preoperative assessment, robotic surgery could be performed feasibly and safely for colon cancer patients with PAS.

Prospective evaluation of bowel function and quality of life after colon cancer surgery – is it time for routine screening for late sequelae?

Aim Bowel dysfunction after colon cancer (CC) surgery is widely neglected in current follow up programmes. This study explored changes in bowel function and quality of life (QoL) from three (3 m) to twelve months (12 m) after surgery in CC patients undergoing right- or left-sided colon resection (RightSCR/LeftSCR) and investigated differences between the two groups 12 m after surgery. Method CC patients undergoing surgical resection in 2018–2020 at five surgical departments were included in this population-based prospective cohort study. Included patients completed electronic surveys consisting of a collection of validated scores 3 m and 12 m after surgery. Results A total of 708 CC patients (423 RightSCR, 285 LeftSCR) were included. In RightSCR, no improvement was observed from 3 m to 12 m in most scores/items, on the contrary, symptom worsening in flatus- and faecal incontinence and urgency was observed (p < 0.05). Also, the proportion of patients rating their bowel function as very good/good decreased (p < 0.05) in this group. In LeftSCR improvement was found in flatus and faecal incontinence, urgency and night-time defaecation (p < 0.02), while no improvement was observed in the remaining scores/items. At 12 m, higher proportions of RightSCR than LeftSCR reported loose stools, incontinence and urgency (all p < 0.001), whereas LeftSCR more often reported hard stools and flatus incontinence (p < 0.05). Among all CC patients 18.3% reported bowel-related impairment of QoL at 12 m with no differences between the two groups. Conclusion From 3 m to 12 m no significant change was observed in the majority of bowel function and QoL scores/items, however, some symptoms worsened in RightSCR, while a few improved in LeftSCR. Bowel dysfunction and impaired QoL were still common in both groups at 12 m, although the symptom pattern differed between the groups. These findings call for a systematic screening for bowel dysfunction to ensure early treatment of symptoms.

Clinical characteristics and prognosis analysis of postoperative patients with stage I-III colon cancer based on SEER database.

To identify the relevant factors affecting the prognosis and survival time of colon cancer and construct a survival prediction model. Data on postoperative stage I-III colon cancer patients were obtained from the Surveillance, Epidemiology, and End Results database. We used R project to analyze the data. Univariate and multivariate Cox regression analyses were performed for independent factors correlated with overall survival from colon cancer. The C-index was used to screen the factors that had the greatest influence in overall survival after surgery in colon cancer patients. Receiver operating characteristic (ROC) curve was made according to the Risk score and calculated to validate the predictive accuracy of the model. In addition, we used decision curve analysis (DCA) to evaluate the clinical benefits and utility of the nomogram. We created a model survival curve to determine the difference in prognosis between patients in the low-risk group and those in the high-risk group. Univariate and multifactor COX analyses showed that the race, Grade, tumor size, N-stage and T-stage were independent risk factors affecting survival time of patients. The analysis of ROC and DCA showed the nomogram prediction model constructed based on the above indicators has good predictive effects. Overall, the nomogram constructed in this study has good predictive effects. It can provide a reference for future clinicians to evaluate the prognosis of colon cancer patients.

Abstract 4380: Pre- and postoperative fecal microbiota and its association with complications after surgery in colon cancer patients

Abstract Introduction: Postoperative complications impact morbidity and mortality of colon cancer patients. Emerging evidence suggests that intestinal microbiota might play a critical role in the development of postoperative complications after gastrointestinal surgery. Here, we studied changes in fecal microbiota composition comparing samples collected before and after colon cancer surgery. Moreover, we examined whether the microbiota composition before surgery was associated with postoperative complications, and we explored potential determinants of the preoperative microbiota in colon cancer patients. Methods: For this study, two fecal samples were provided by 78 patients with colon cancer. The first (preoperative) sample was collected shortly after diagnosis and before (median and interquartile (IQR) range of 4 (2-6) days) colon cancer surgery. The second (postoperative) sample was collected approximately 6 weeks (median and IQR of 42 (37-47) days) after surgery and before start of adjuvant chemotherapy (whenever applicable). Based on 16S ribosomal RNA gene amplicon sequencing, the fecal microbiota diversity and composition were determined. Preoperative microbiota composition of patients who developed postoperative complications in the 30 days following surgery (n=18, 23%) was compared to those who did not (n=60, 77%) using univariate and multivariate analyses. Explorative random forest analyses were conducted to identify predictors of complication status, with relative abundance of the core genera, sex, age, fecal calprotectin levels, dietary fiber intake, body mass index, smoking status, ASA classification, cancer stage and tumor location being considered as potential predictors. Results: After surgery, microbial alpha diversity was reduced compared to the preoperative situation, whereas compositional changes over time only reached statistical significance for Lachnospiraceae NK4A136 and Coprococcus 1, which both decreased in relative abundance after surgery. Already before the start of surgery, relative abundance of the genera Bacteroides (10% vs 6%) and Lachnoclostridium (0.6% vs 0.2%) appeared to be higher in patients with complications versus those with uncomplicated recovery. In a prediction analysis, current smoking and relative abundance of Lachnoclostridium were identified as most profound predictors of complication status. Fecal calprotectin levels and current smoking status explained most (together 6%) of the overall variation in microbiota composition before surgery. Conclusion: In this study, higher relative abundances of the genera Bacteroides and Lachnoclostridium before surgery were associated with postoperative complications in patients with colon cancer. Future studies should expand on the potential causal and pathogenic routes underlying these observations. Citation Format: Dieuwertje E. Kok, Jannigje G. Kers, Hendriek C. Boshuizen, Niels Klaassen, Henk K. van Halteren, Flip M. Kruyt, Marjolein L. Smidt, Johannes H. De Wilt, Annemarie Boleij, Ellen Kampman, Erwin G. Zoetendal. Pre- and postoperative fecal microbiota and its association with complications after surgery in colon cancer patients. [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2023; Part 1 (Regular and Invited Abstracts); 2023 Apr 14-19; Orlando, FL. Philadelphia (PA): AACR; Cancer Res 2023;83(7_Suppl):Abstract nr 4380.

The impact of a multispecialty operative team on colorectal cancer surgery: A retrospective study from a would-be medical center in Taiwan.

Some studies showed that when distant metastasis or locally advanced tumors were observed, the participation of 2 or more operating surgeons (combined surgery) in the operation could improve the prognosis of patients. The multispecialty operative team would perform combined surgery in colon cancer patients with some complications since 2015.The goal of this study is to confirm performing combined surgery would improve the outcomes of colon cancer patients.A retrospective observational study was conducted, which involved all colon cancer patients between November 2015 and December 2019 at one would-be medical center. Patients were divided into 3 cohorts: those with complicated cases and had combined surgery (C_2S), those with complicated cases and had surgery performed by a single surgeon (C_1S), and those with uncomplicated cases and had surgery performed by a single surgeon (NC_1S). Overall survival and disease-free survival were compared among the 3 groups.A total of 296 colon cancer patients during the study period. Among them, 35 were C_2S, 87 were C_1S, and 174 were NC_1S. Patients in the NC_1S group had significantly higher 12-, 24-, and 36-month OS rates compared to those in the C_1S group (P < .01). In contrast, there was no significant difference in overall survival among patients in the NC_1S and C_2S group (P =.15).The quality of surgery must be impact the prognosis, especially in the individual who was complicated case, the survival in patients who had surgery performed by multispecialty operative team would be improved.

Prognostic value of carcinoembryonic antigen levels before and after curative surgery in colon cancer patients.

PurposeCEA is a useful tumor marker for colon cancer. The aim of this study was to investigate the prognostic value of changes in CEA levels before and after surgery in colon cancer patients who underwent radical surgery.MethodsA total of 601 colon cancer patients who underwent radical surgery from January 2007 to December 2017 at a single institution were evaluated. Patients were categorized according to preoperative and postoperative CEA levels. We adjusted patient characteristics using propensity score matched analysis between groups and compared survival outcomes according to changes in CEA levels before and after surgery.ResultsAccording to the preoperative and postoperative CEA levels, patients were classified into 3 groups: group 1, ≤5 and ≤5 ng/mL, respectively (n = 407); group 2, >5 and ≤5 ng/mL, respectively (n = 127); and group 3 (>5 and >5 ng/mL, respectively (n = 67). Postoperative CEA elevation was associated with adverse clinical features. Before and after matching, the patients in group 3 showed significantly lower disease-free survival and overall survival rates compared to the patients in group 1 and group 2. In multivariate analysis, changes in CEA levels were an independent prognostic factor of overall survival (P = 0.041).ConclusionThe changes in CEA levels before and after surgery can be a useful prognostic factor for disease-free survival and overall survival in colon cancer patients.

Laparoscopic surgery for colon cancer

Abstract Background To evaluate a new procedure in daily clinical practice, it might not be sufficient to rely exclusively on the findings of randomized clinical trials (RCTs). This is the first systematic review providing a synthesis of the most important RCTs and relevant retrospective cohort studies on short- and long-term outcomes of laparoscopic surgery in colon cancer patients. Materials and methods In a literature search, more than 1800 relevant publications on the topic were identified. Relevant RCTs and representative high-quality retrospective studies were selected based on the widely accepted Strengthening the Reporting of Observational Studies in Epidemiology (STROBE) criteria. Finally, 9 RCTs and 14 retrospective cohort studies were included. Results Laparoscopic surgery for colon cancer is associated with a slightly longer duration of surgery, but a variety of studies show an association with a lower rate of postoperative complications and a shorter duration of hospital stay. Particularly in older patients with more frequent comorbidities, laparoscopy seems to contribute to decreasing postoperative mortality. Concerning long-term oncologic outcomes, the laparoscopic and open techniques were shown to be at least equivalent. Conclusion The findings of the existing relevant RCTs on laparoscopic surgery for colon cancer are mostly confirmed by representative retrospective cohort studies based on real-world data; therefore, its further implementation into clinical practice can be recommended.

Short-term outcomes after self-expandable metal stent insertion for obstructing colon cancer: a retrospective cohort study.

ABSTRACTBACKGROUND: Self-expanding metal stents (SEMS) are used as a bridge to surgery for colon cancer patients as an alternative to emergency surgery. Currently, there is a paucity of literature from Saudi Arabia on the preoperative usage of SEMS.OBJECTIVE: Determine whether SEMS are associated with a higher rate of complications.DESIGN: Retrospective cohort studySETTINGS: Tertiary care hospital in Saudi Arabia.PATIENTS AND METHODS: In patients diagnosed with obstructing colon cancer, up-front surgical resection was compared with insertion of SEMS followed by surgical resection between the years 2009 and 2013.MAIN OUTCOME MEASURES: Rate of stent-related short-term complications. Secondary endpoint, postoperative complications.SAMPLE SIZE: 65.RESULTS: Twenty-four (36.9%) patients underwent SEMS placement; 41 (63.1%) underwent primary surgery. The median (interquartile range) hospital stay was significantly higher among the SEMS group (13 [8.5] days versus 7 [3] days in the primary surgery group, P<.001). Five patients (20.8%) in the SEMS group developed complications: 2 (8.3%) perforations, 2 (8.3%) obstructions, and 1 (4.2%) stent migrations.CONCLUSION: SEMS is associated with longer hospital stays and short-term serious complications. Further research should be conducted, preferably with a larger sample size.LIMITATIONS: Retrospective design, small sample size.CONFLICT OF INTEREST: None.

The Short- and Long-Term Feasibility of Laparoscopic Surgery in Colon Cancer Patients with Bulky Tumors

BackgroundCompared to open surgery for colon cancer, randomized controlled trials have shown that laparoscopic approaches have equivalent short- and long-term outcomes. However, the feasibility of laparoscopy for removal of bulky tumors has not been evaluated. The aim of our study was to determine the short- and long-term feasibility of laparoscopic surgery for bulky (> 8 cm) colon cancer. MethodsA total of 80 patients with bulky tumors (defined as greater than 8 cm in diameter) underwent curative resection from July 2004 to July 2014. Short- and long-term outcomes were compared between patients undergoing laparoscopic (n = 48) and open (n = 32) resection. ResultsCompared to open, the operative time was significantly longer (213 vs. 148 min, p < 0.001), return of bowel function quicker (time to oral intake; 2 vs. 5 days, p < 0.001), and length of stay shorter (10 vs. 13 days, p < 0.001) in the laparoscopic group. Five-year cancer-specific and relapse-free survival was similar with no patients developing local recurrence in either group. ConclusionsLaparoscopic resection of colon cancers greater than 8 cm in diameter is feasible and oncologically safe with better short-term and equivalent long-term outcomes compared to open surgery.

Laparoscopic surgery in colon cancer patients treated with chronic anti-thrombotic therapy.

Anti-thrombotic medications are commonly used for the treatment and prevention of cardiovascular diseases. Laparoscopic resection of colon cancer has generally been accepted with favorable outcomes being reported in randomized control trials. However, the safety and efficacy of laparoscopic surgery for colon cancer patients receiving chronic anti-thrombotic therapy (AT) remain unclear. We identified 951 patients who underwent elective resection for colon cancer between 2009 and 2016 from our database. Patients were classified according to the surgical approach and chronic AT. Clinicopathological factors and surgical outcomes were analyzed between patient groups. Patients' backgrounds were matched using propensity scores in laparoscopic surgery. Anti-thrombotic drugs were chronically used in 135 patients. Among 714 patients who underwent laparoscopy-assisted surgery, 96 received AT. The laparoscopic approach was superior to open surgery in terms of bleeding, surgical site infections, and hospital stay in patients receiving AT. In laparoscopy-assisted surgery, the AT group patients were older and showed lower hemoglobin and albumin levels than those not receiving AT (non-AT group), and were predominantly male. After propensity score matching, estimated blood loss and operative times were similar between the two groups (93 matched patients). The frequencies of postoperative bleeding (2.2%) and thrombotic complications (0%) in the AT group did not significantly differ from those in the non-AT group (1.1 and 0%, respectively). Moreover, AT did not affect survivals. Laparoscopic approach appears to be safer and beneficial for colonic cancer patients receiving long-term AT. Bleeding and thrombotic events associated with laparoscopic surgery were not significantly affected by AT.

A Population-Based Study on Clinical Outcomes and Medical Costs of Laparoscopic Versus Open Surgery for Colon Cancer Patients in Taiwan

A Population-Based Study on Clinical Outcomes and Medical Costs of Laparoscopic Versus Open Surgery for Colon Cancer Patients in Taiwan

Incidence of minimally invasive colorectal cancer surgery at National Comprehensive Cancer Network centers.

Laparoscopic colectomy has been shown to have equivalent oncologic outcomes to open colectomy for the management of colon cancer, but its adoption nationally has been slow. This study investigates the prevalence and factors associated with laparoscopic colorectal resection at National Comprehensive Cancer Network (NCCN) centers. Data on patients undergoing surgery for colon and rectal cancer at NCCN centers from 2005 to 2010 were obtained from chart review of medical records for the NCCN Outcomes Project and included information on socioeconomic status, insurance coverage, comorbidity, and physician-reported Eastern Cooperative Oncology Group (ECOG) performance status. Associations between receipt of minimally invasive surgery and patient and clinical variables were analyzed with univariate and multivariable logistic regression. All statistical tests were two-sided. A total of 4032 patients, diagnosed between September 2005 and December 2010, underwent elective colon or rectal resection for cancer at NCCN centers. Median age of colon cancer patients was 62.6 years, and 49% were men. The percent of colon cancer patients treated with minimally invasive surgery (MIS) increased from 35% in 2006 to 51% in 2010 across all centers but varied statistically significantly between centers. On multivariable analysis, factors associated with minimally invasive surgery for colon cancer patients who had surgery at an NCCN institution were older age (P = .02), male sex (P = .006), fewer comorbidities (P ≤ .001), lower final T-stage (P < .001), median household income greater than or equal to $80000 (P < .001), ECOG performance status = 0 (P = .02), and NCCN institution (P ≤ .001). The use of MIS increased at NCCN centers. However, there was statistically significant variation in adoption of MIS technique among centers.

Minimally invasive surgery in colon cancer patients leads to improved short-term outcomes and excellent oncologic results

Background Minimally invasive surgery (MIS) techniques are beneficial compared with open techniques. There is a paucity of data of the potential advantages of MIS in colon cancer surgery for veterans. Therefore, we hypothesize that use of MIS in colon cancer resections in a Veterans Affairs Medical Center will lead to improved short-term outcomes without compromising oncologic outcomes. Methods A retrospective analysis of a prospectively maintained database was performed. We compared surgical, short-term, and oncologic outcomes in MIS versus open surgery. Results MIS patients had significantly less blood loss, surgical time, days to return of bowel function, and hospital and intensive care unit stays. Also, they had a greater and more adequate lymphadenectomy, and were less likely to experience a postoperative complication. Survival analyses showed no difference in overall and disease-free survival. Conclusions The use of MIS in colon cancer leads to improved short-term outcomes and similar oncologic outcomes when compared with open surgery.

Surgical treatment of colon cancer in patients older than age 80.

6071 Background: Individuals >80 years represent a growing proportion of colon cancer patients and create a decision-making challenge for surgeons due to frequent comorbidities. Our objective was to describe patterns of surgery in colon cancer patients >80 years and examine outcomes with and without colectomy. Methods: Medicare beneficiaries >80 years with colon cancer diagnosed from 1992-2005 were identified from the Surveillance, Epidemiology, and End Results-Medicare database; stage IV was excluded. χ2 and two-way ANOVA assessed differences in patient characteristics. Kaplan-Meier survival analysis determined one-year overall and disease-specific survival. Results: Of 35,080 patients, 80% underwent colectomy within 90 days of diagnosis. 46% were for urgent/emergent reasons. Post-operative complications occurred in 4%, and 9% died within 30 days. Patients not selected for colectomy had more comorbidities (higher HCC risk score), were more likely to have a wheelchair and use home oxygen (Table). 11% of these non-operative patients ultimately required a cancer-related intervention (delayed colectomy 9%, stoma 1.4%, stent 0.4%). One-year overall survival with and without colectomy was 77 vs. 58%. One-year disease-specific survival was 89 vs. 76%. Conclusions: Most older colon cancer patients undergo colectomy, although many for urgent/emergent reasons. Disease-specific survival after colectomy is greater than overall survival, confirming that many die due to competing causes. Further research should focus on improving mechanisms to identify those patients >80 years at increased risk for a poor outcome after elective colectomy. Colectomy(n=28,070) No colectomy(n=7,010) P value Age at diagnosis* 85.0 (4.2) 85.9 (4.6) <0.0001 Male gender 37% 39% <0.001 HCC risk score** 2.32 (1.5) 2.58 (1.8) <0.0001 Mobility No device 91.7% 87.6% <0.001 Crutch, cane, or walker 4.6% 5.9% Wheelchair 3.7% 6.6% Home oxygen use 2.3% 3.8% <0.001 No. of hospitalizations in year prior to diagnosis* 1.49 (0.90) 1.70 (1.16) 0.010 Surgical evaluation after diagnosis 61% 46% <0.001 SEER historic stage Local 46.6% 47.4% <0.001 Regional 52.1% 23.3% Unstaged 1.2% 29.3% Abbreviation: HCC, hierarchical condition categories (measure of comorbidity). * Mean, standard deviation.

Comparison of nodal positivity between SLNM vs conventional surgery in colon cancer patients with

BackgroundExamination of ≥12 lymph nodes (LNs) ensures accurate staging in colon cancer. The aim of this study was to compare nodal positivity between sentinel LN mapping (SLNM) and conventional surgery in patients with <12 and ≥12 LNs harvested. MethodsFrom 1993 to 2008, 407 and 380 patients with colon cancer underwent SLNM and conventional surgery, respectively. Total LNs harvested and nodal positivity were analyzed. Patients were grouped according to number of LNs harvested: 2 to 11, 12 to 25, or >25. ResultsThe average numbers of LNs harvested in the groups with 2 to 11, 12 to 25, and >25 LNs harvested for SLNM and conventional surgery, respectively, were 8.3 and 7.1 (P < .0001), 17.2 and 16.5 (P = .09), and 34.2 and 32.1 (P = .40). Nodal positivity for SLNM and conventional surgery in the groups with <12 and ≥12 LNs harvested was 42% and 29% (P = .01) and 50% and 36% (P = .003), respectively. Overall nodal positivity was 47% for SLNM and 32% for conventional surgery (P < .0001). When SLNM with 2 to 11 LNs was compared with conventional surgery with 12 to 25 LNs, nodal positivity was 42% versus 36% (P = .35). ConclusionsSLNM possessed higher nodal positivity compared with conventional surgery. SLNM is a valuable adjunct to accurate nodal staging in colon cancer.

Circulating cytokeratin 18 fragments and activation of dormant tumor cells in bone marrow of cancer patients (Review)

In cancer patients detection of systemic disease is of great importance to obtain prognostic information and to guide therapy. Bone marrow (BM) seems to be a common homing tissue for the early spread of tumor cells from various epithelial tumors; however, verification of the prognostic significance of BM-disseminated tumor cells (BM-DTCs), is restricted to breast cancer so far. These cells may be dormant for a long time, and signals triggering their activation leading to recurrence remain to be characterized. A recent study involving metastatic breast cancer patients reported that the shortest disease-free survival is correlated with cytokeratin (CK)-negative BM aspirates and that CK-positive BM-DTCs correspond to dormant tumor cells. Soluble CK fragments in serum including CK18 and 19 (measured as TPS and CYFRA 21-1, respectively) and caspase-cleaved CK18 are widely used to monitor tumor progression and response to therapy, actually indicating proliferation and/or necrotic/apoptotic cell death. In order to assess the source of the CK fragments, we used determinations of CK18 and caspase-cleaved CK18 fragments in serum samples before and after radical tumor surgery in colon cancer patients. Elevated serum concentrations of CK18 were found to persist in patients with a high incidence of BM-DTCs, and high perioperative levels of caspase-cleaved CK18 fragments were detected in patients with early relapses, respectively. These results indicate that in some patients at increased risk of recurrence disseminated cell populations exist that are responsible for the release of the bulk of CK fragments after removal of the apparently nonmetastatic tumor. In good agreement with the results in metastatic breast cancer patients, release of CK18 or 19 fragments by BM-DTCs seem to indicate disseminated tumor cells mainly in a dormant state, whereas caspase-cleaved CK18 may indicate skipping of this latent phase and early progression. Therefore, caspase cleavage of CKs in intact tumor cells seems to accompany or is involved in the differentiation leading from dormant to progressively active disseminated tumor cells. Release of respective CK fragments would result in an apparent clearing of CK-positive cells in BM, leaving malignant cells that have possibly undergone an epithelial-mesenchymal transition. Micrometastatic cancer cell lines derived from breast cancer patients were found to display loss of epithelial CK8, 18 and 19 as well as ectopic expression of vimentin as in mesenchymal cells. In conclusion, degradation of CKs may represent a marker indicating reactivation of dormant tumor cells in BM.

Clinical Significance of Lymph Node Micrometastasis in Stage I and II Colon Cancer

A 25% rate of recurrence after performing complete resection in node-negative colon cancer patients suggests that their nodal staging is frequently suboptimal. Moreover, the value of occult cancer cells in tumor-free lymph nodes still remains uncertain. The authors evaluated the prognostic significance of the pathologic parameters, including the lymph node occult disease (micrometastases) detected by immunohistochemistry, in patients with node-negative colon cancer. The study included 160 patients with curatively resected stage I or II colon cancer and they were without rectal cancer. 2852 lymph nodes were re-examined by re-do hematoxylin and eosin (H-E) staining and immunohistochemical staining. The detection rates were compared with the clinicopathologic characteristics and with the cancer-specific survival. Occult metastases were detected in 8 patients (5%). However, no clinicopathologic parameter was found to be correlated with the presence of micrometastasis. Twenty patients developed recurrence at a median follow-up of 45.7 months: 14 died of colon cancer and 9 died from noncancer-related causes. Univariate analysis showed that lymphatic invasion and the number of retrieved lymph nodes significantly influenced survival, and multivariate analysis revealed that the stage, the number of retrieved lymph nodes and lymphatic invasion were independently related to the prognosis. Inadequate lymph node retrieval and lymphatic invasion were found to be associated with a poorer outcome for node-negative colon cancer patients. The presence of immunostained tumors cells in pN0 lymph nodes was found to have no significant effect on survival, but these tumor were identified by re-do H-E staining. Maximal attention should be paid to the total number of lymph nodes that are retrieved during surgery for colon cancer patients.