The Current Role of Robotics in Colorectal Surgery

[Robotic rectal surgery]

Colorectal cancer is one of the most frequent cancerous diseases in industrial nations, whereby tumors of the rectum constitute approximately 30-40% of all colorectal cancers. In addition to the implementation and establishment of novel neoadjuvant concepts for the treatment of rectal cancer, there has been a continuous evolution of surgical techniques in recent years towards minimally invasive surgery. In this respect robot-assisted surgery has become more and more popular despite seemingly weak evidence regarding clinical benefits and the not to be ignored economic aspects; however, recently published high-quality studies provide new evidence showing advantages for a robotic resection in patients suffering from rectal cancer. Thus, the progressive implementation of robotic surgical systems is increasingly attaining a scientific foundation.

Surgical management of pediatric Crohn's disease

Management of pediatric-onset Crohn's disease uniquely necessitates consideration of growth, pubertal development, psychosocial function and an increased risk for multiple future surgical interventions. Both medical and surgical management are rapidly advancing; therefore, it is increasingly important to define the role of surgery and the breadth of surgical options available for this complex patient population. Particularly, the introduction of biologics has altered the disease course; however, the ultimate need for surgical intervention has remained unchanged. This review defines and evaluates the surgical techniques available for management of the most common phenotypes of pediatric-onset Crohn's disease as well as identifies critical perioperative considerations for optimizing post-surgical outcomes.

Knowledge, Attitude, Awareness, and Future Expectations of Robotic Surgery in Patients Attending Surgical Specialties Clinics

Introduction The use of robotic-assisted surgeries (RAS) has been growing in surgical specialties. It allows surgeons to perform higher-quality operations with fewer complications, mortality, and morbidity. However, there are a lot of misconceptions about RAS among patients. Therefore, our study aimed to assess the knowledge, attitude, awareness, and future expectations of RAS in patients attending surgical clinics. Methods  A cross-sectional study was conducted in King Abdulaziz Medical City (KAMC) surgical clinics in Riyadh, Saudi Arabia. All participants <18 years of age were excluded. The questionnaire was distributed to 304 patients attending surgical clinics with a confidence level of 95% and a margin of error of 5%. Cluster sampling was used since the respondents were from multiple surgical specialties. Finally, multivariate analysis was performed to assess participants' preference for robotic surgery. Results Most participants (58.6%, n=178) were between 21 and 40 years old, and males were 52% of the participants. Many respondents thought a robot did not do the surgery. 70.7% of respondents had not heard of robotic surgery, with the media being the most common source of information. Internal damage was the prevalent concern (51.0%, n= 155) in malfunctions of robotic surgery. A significant relationship was found between participants from 21 to 40 years of age and a stronger preference for robotic surgery (p=.027). Respondents who preferred robotic surgery were discovered to have a significant relationship with participants who thought robotic surgery was safer and had better results (p<.001). 13.9% of participants who did not prefer robotic surgery also took cost into account significantly (χ2=28.93, p<.001, Cramer's V=.22). 67.2% (n=43) of respondents who preferred robotic surgery believed it might eventually replace present practices. Conclusion Our study concluded that the majority did not favor or were unsure whether to undergo robotic surgeries or not. However, most participants had some misconceptions and a lack of awareness about robotic surgeries. Raising awareness among patients can improve the mutual decision-making between them and their treating physician.

Advantage of log odds of positive lymph nodes in prognostic evaluation of patients with early-onset colon cancer

BACKGROUND

Colon cancer (CC) is one of the most common cancers of the digestive tract, the third most common cancer worldwide, and the second most common cause of cancer-related deaths. Previous studies have demonstrated a higher risk of lymph node metastasis (LNM) in young patients with CC. It might be reasonable to treat patients with early-onset locally advanced CC with extended lymph node dissection. However, few studies have focused on early-onset CC (ECC) patients with LNM. At present, the methods of predicting and evaluating the prognosis of ECC patients with LNM are controversial.

AIM

To compare the prognostic values of four lymph node staging indices and establish the best nomogram for patients with ECC.

METHODS

From the data of patients with CC obtained from the Surveillance, Epidemiology, and End Results (SEER) database, data of young patients with ECC (≤ 50 years old) was screened. Patients with unknown data were excluded from the study, while the remaining patients were included. The patients were randomly divided into a training group (train) and a testing group (test) in the ratio of 7:3, while building the model. The model was constructed by the training group and verified by the testing group. Using multiple Cox regression models to compare the prediction efficiency of LNM indicators, nomograms were built based on the best model selected for overall survival (OS) and cause-specific survival (CSS). In the two groups, the performance of the nomogram was evaluated by constructing a calibration plot, time-dependent area under the curve (AUC), and decision curve analysis. Finally, the patients were grouped based on the risk score predicted by the prognosis model, and the survival curve was constructed after comparing the survival status of the high and low-risk groups.

RESULTS

Records of 26922 ECC patients were screened from the SEER database. N classification, positive lymph nodes (PLN), lymph node ratio (LNR) and log odds of PLN (LODDS) were considered to be independent predictors of OS and CSS. In addition, independent risk factors for OS included gender, race, marital status, primary site, histology, grade, T, and M classification, while the independent prognostic factors for CSS included race, marital status, primary site, grade, T, and M classification. The prediction model including LODDS is composed of minimal Akaike information criterion, maximal concordance indexes, and AUCs. Factors including gender, race, marital status, primary site, histology, grade, T, M classification, and LODDS were integrated into the OS nomogram, while race, marital status, primary site, grade, T, M classification, and LODDS were included into the CSS nomogram. The nomogram representing both cohorts had been successfully verified in terms of prediction accuracy and clinical practicability.

CONCLUSION

LODDS is superior to N-stage, PLN, and LNR of ECC. The nomogram containing LODDS might be helpful in tumor evaluation and clinical decision-making, since it provides an appropriate prediction of ECC.

Open, Laparoscopic, and Robotic Approaches to Treat Colorectal Cancer: A Comprehensive Review of Literature

Surgery is usually required to treat colorectal cancer (CRC). Medical technology has advanced, providing various approaches to tackle this disease. Different surgeries are available, such as laparoscopic surgery, single-incision laparoscopic surgery, natural orifice transluminal endoscopic surgery, and robotic surgery. Laparoscopic surgery has several benefits including reduced blood loss and shorter recovery time. It can also improve lung function and minimize complications. However, it requires more time to perform and has a higher risk of complications during the procedure. Robotic surgery provides a three-dimensional view of the surgical area allowing for greater precision in rectal surgeries and access to difficult-to-reach pelvic regions. This method utilizes robotics technology which reduces surgical time and speeds up recovery for patients. There are various surgical options available for treating CRC; however, laparoscopic surgery and robotic surgery offer unique advantages despite their own drawbacks. As technology continues to evolve, medical techniques will continue improving existing methods while providing new options resulting in better outcomes for patients. Compared to laparoscopy, robotic surgery has a lower rate of operative conversions and a shorter learning curve. However, it also has some drawbacks, such as a longer docking time, lack of tactile sensation, and higher cost. Therefore, the choice of surgical method should depend on patient characteristics, surgeon preference and expertise, and available resources. Currently, specialized centers offer robotic surgeries which are more expensive and take longer compared to open and laparoscopic approaches. Nonetheless, they are considered safe and feasible when compared to traditional surgery. Short-term outcomes for robotic surgeries are better, while long-term postoperative complication rates remain similar. However, there is a need for additional well-defined randomized control trials conducted across multiple centers to validate the use of robotic surgery over open and laparoscopic approaches. Improving patient care and outcomes is the objective of this comprehensive literature overview on surgical approaches for CRC.

A Review of Robotic Surgery in Colorectal Surgery

Colorectal surgery is a treatment for colorectal lesions. Technological advancements have given the rise to robotic colorectal surgery, a procedure that limits excessive blood loss via 3D pin-point precision capabilities during surgeries. The aim of this study is to review robotic surgery in colorectal treatment procedures in order to dictate its ultimate merits. This is a literature review utilising PubMed and Google Scholar; it only includes case studies and case reviews related to robotic colorectal surgeries. Literature reviews are excluded. We incorporated abstracts from all articles and full publications were examined to compare the benefits of robotic surgery in colorectal treatments. The number of articles reviewed was 41 literature spanning from 2003 to 2022. We found that robotic surgeries yielded finer marginal resections, greater amounts of lymph node resections and earlier recovery of bowel functions. The patients also spent less time in hospital after surgery. The obstacles on the other hand are it costs longer operative hours and further training, which is expensive. Studies show robotic approach is a choice for treating rectal cancer. However further studies would be needed to conclude the best approach. This is especially true with patients treated for anterior colorectal resections. Based on the evidence it's safe to say that the upsides outweigh the downsides, but advancements and further research in robotic colorectal surgeries are still necessary to reduce operative hours and cost. Surgical societies should also take the initiative and set up effective training programmes for colorectal robotic surgeries, as trained physicians result in better treatment outcomes.

Pediatric colorectal robotic surgery

Robotic colorectal surgery allows adult and pediatric surgeons to overcome the technical limitations of laparoscopic surgery. It also provides improved ergonomics in the field of surgery. Robotic surgery has several advantages in colorectal operations that require complex minimally invasive skills including anorectal malformations, Hirschsprung disease, and inflammatory bowel disease. In this section, we discuss the key aspects of colorectal surgery where robotic instrumentation seems ideal.

Robotic-Assisted versus Laparoscopic Proctectomy with Ileal Pouch-Anal Anastomosis for Ulcerative Colitis: An Analysis of Clinical and Financial Outcomes from a Tertiary Referral Center

Background: Robotic-assisted colorectal surgery is gaining popularity, but limited data are available on the safety, efficacy, and cost of robotic-assisted restorative proctectomy with the construction of an ileal pouch and ileal pouch-anal anastomosis (IPAA) for ulcerative colitis (UC). Methods: A retrospective study was conducted comparing consecutively performed robotic-assisted and laparoscopic proctectomy with IPAA between 1 January 2016 and 31 September 2021. In total, 67 adult patients with medically refractory UC without proven dysplasia or carcinoma underwent surgery: 29 operated robotically and 38 laparoscopically. Results: There were no differences between both groups regarding postoperative complications within 30 days according to Clavien-Dindo classification’ grades 1−5 (51.7% vs. 42.1%, p = 0.468) and severe grades 3b−5 (17.2% vs. 10.5%, p = 0.485). Robotic-assisted surgery was associated with an increased urinary tract infection rate (n = 7, 24.1% vs. n = 1, 2.6%; p = 0.010) and longer operative time (346 ± 65 min vs. 281 ± 66 min; p < 0.0001). Surgery costs were higher when operated robotically (median EUR 10.377 [IQR EUR 4.727] vs. median EUR 6.689 [IQR EUR 3.170]; p < 0.0001), resulting in reduced total inpatient profits (median EUR 110 [IQR EUR 4.971] vs. median EUR 2.853 [IQR EUR 5.386]; p = 0.001). Conclusion: Robotic-assisted proctectomy with IPAA can be performed with comparable short-term clinical outcomes to laparoscopy but is associated with a longer duration of surgery and higher surgery costs. As experience increases, some advantages may become evident regarding operative time, postoperative recovery, and length of stay. The robotic procedure might then become cost-efficient.

Improved Morbidity, Mortality, and Cost with Minimally Invasive Colon Resection Compared to Open Surgery

Background and Objectives:

Despite the growth of minimally invasive surgery (MIS) in many specialties, open colon surgery is still routinely performed. The purpose of this study was to compare outcomes and costs between open colon and minimally invasive colon resections.

Methods:

We analyzed outcomes between January 1, 2016 and December31, 2018 using the Vizient® clinical database. Demographics, hospital length of stay, readmissions, complications, mortality, and costs were compared between patients undergoing elective open and minimally invasive colon resections. For bivariate analysis, Wilcoxon rank-sum test was used for continuous variables and χ² test was used for categorical variables. Multiple Logistic and Quintile regression were used for multivariable analyses.

Results:

A total of 88,405 elective colon resections (open: 56,599; minimally invasive: 31,806) were reviewed. A significantly larger proportion of patients undergoing minimally invasive surgery were obese (body mass index > 30) compared to those undergoing open surgery (71.4% vs. 59.6%; p < 0.0001). As compared to minimally invasive colectomy, open colectomy patients had: a longer median length of stay [median (range): 7 (4–13) days vs. 4 (3 – 6) days, p < 0.0001], higher 30-day readmission rate [n = 8557 (15.1%) vs. 2815 (8.9%), p < 0.0001], higher mortality [n = 2590 (4.4%) vs. 107 (0.34%), p < 0.0001], and a higher total direct cost [median (range): $13,582 (9041–23,094) vs. $9013 (6748 – 12,649), p < 0.0001]. Multivariable models confirmed these findings.

Conclusion:

Minimally invasive colon surgery has clear benefits in terms of length of stay, readmission rate, mortality and cost, and the routine use of open colon resection should be revaluated.

Teaching and Training Surgeons in Robotic Colorectal Surgery

Robotic surgery is becoming more popular among practicing physicians as a new modality with improved visualization and mobility (1-2). As patients also desire minimally invasive procedures with quicker recoveries, there is a desire for new surgical residents and fellows to pursue robotic techniques in training (3-4). To develop a new colorectal robotics training program, an institution needs a well-formulated plan for the trainees and mentors with realistic expectations. The development of a robotics training program has potential obstacles, including increased initial cost, longer operative times, and overcoming learning curves. We have devised a four-phase training protocol for residents in colorectal surgical fellowship. Each of these phases attempts to create a curricular framework that outlines logical progression and sets expectations for trainees, Program Directors, and residency faculty. Phase zero begins prior to fellowship and is preparatory. Phase one focuses on an introduction to robotics with learning bedside console troubleshooting and simulation exercises. Phase Two prioritizes operative experience and safety while completing steps independently in a progressive fashion. Phase Three polishes the resident prior to graduation for future practice. We recommend frequent evaluation and open-mindedness while establishing a focused robotics program. The end goal is to graduate fellows with an equivalency certificate who can continue to practice colorectal robotic surgery.

2D vs 3D laparoscopic right colectomy: A propensity score-matching comparison of personal experience with systematic review and meta-analysis

BACKGROUND

The benefits of laparoscopic approach for right colectomy have been well established. However, the technical difficulty to construct the intra-corporeal anastomosis is still cumbersome.

AIM

To analyze the results of 3D and 2D laparoscopic right colectomy and to compare it to the published series through a systematic review and meta-analysis.

METHODS

A retrospective study with propensity score matching analysis of patients undergoing laparoscopic right colectomy at Umbria2 Hospitals from January 2014 to March 2020 was performed. A systematic review was accomplished comparing 2D and 3D right colectomy.

RESULTS

In the personal series 47 patients of the 2D group were matched to 47 patients of the 3D group. The 3D group showed a favorable trend in terms of mean operative time (170.7 ± 32.9 min vs 183.8 ± 35.4 min; P = 0.053) and a significant lower anastomotic time (16.9 ± 2.3 min vs 19.6 ± 2.9 min, P < 0.001). The complete mesocolic excision (CME) subgroups analysis showed a shorter anastomotic time (16.5 ± 1.8 min vs 19.9 ± 3.0 min; P < 0.001) and operative time (175.0 ± 38.5 min vs 193.7 ± 37.1 min; P = 0.063) in the 3D group. Six studies and our series were included in the meta-analysis with 551 patients (2D group: 291; 3D group: 260).The pooled analysis demonstrated a significant difference in favour of the 3D group regarding the operative time (P < 0.001) and the anastomotic time (P < 0.001) while no differences were identified between groups in terms of blood loss (P = 0.827), LNH yield (P = 0.243), time to first flatus (P = 0.333), postoperative complications (P = 0.718) and length of stay (P = 0.835).

CONCLUSION

The meta-analysis results showed that 3D laparoscopic right colectomy shortens operative and anastomotic time without affecting the standard lymphadenectomy. In our series, the advantage of the 3D system becomes evident when CME and/or more complex associated procedure are requested significantly reducing both the total operative and the anastomotic time.

Robotic versus laparoscopic surgery for colorectal cancer: a case-control study

BACKGROUND

Robotic resections represent a novel approach to treatment of colorectal cancer. The aim of our study was to critically assess the implementation of robotic colorectal surgical program at our institution and to compare it to the established laparoscopically assisted surgery.

PATIENTS AND METHODS

A retrospective case-control study was designed to compare outcomes of consecutively operated patients who underwent elective laparoscopic or robotic colorectal resections at a tertiary academic centre from 2019 to 2020. The associations between patient characteristics, type of operation, operation duration, conversions, duration of hospitalization, complications and number of harvested lymph nodes were assessed by using univariate logistic regression analysis.

RESULTS

A total of 83 operations met inclusion criteria, 46 robotic and 37 laparoscopic resections, respectively. The groups were comparable regarding the patient and operative characteristics. The operative time was longer in the robotic group (p < 0.001), with fewer conversions to open surgery (p = 0.004), with less patients in need of transfusions (p = 0.004) and lower reoperation rate (p = 0.026). There was no significant difference between the length of stay (p = 0.17), the number of harvested lymph nodes (p = 0.24) and the overall complications (p = 0.58).

CONCLUSIONS

The short-term results of robotic colorectal resections were comparable to the laparoscopically assisted operations with fewer conversions to open surgery, fewer blood transfusions and lower reoperation rate in the robotic group.

Accurate nomograms with excellent clinical value for locally advanced rectal cancer

Background

Rectal cancer accounts for approximately 30–50% of colorectal cancer. Despite its widespread use and convenience, the American Joint Committee on Cancer (AJCC) staging system for predicting survival is prone to inaccuracy, even including a survival paradox for locally advanced rectal cancer (LARC). An accurate risk stratification of LARC is essential for proper treatment selection and prognostic evaluation. Therefore, we aimed to create prognostic nomograms for LARC capable of assessing overall survival (OS) and cancer-specific survival (CSS) precisely and intuitively.

Methods

The Surveillance, Epidemiology, and End Results (SEER) database was accessed. All of the significant variables in the multivariate analysis were integrated to build the nomograms.

Results

Data for a total of 23,055 patients with LARC were collected from the SEER database in this study. Based on the multivariate Cox regression analysis, both OS and CSS were significantly associated with 13 variables: age, marital status, race, pathological grade, histological type, T stage, N stage, surgery, radiotherapy, chemotherapy, regional nodes examined (RNE), tumor size, and carcinoembryonic antigen (CEA). These were included in the construction of nomograms for OS and CSS. Time-dependent receiver operating characteristic (ROC) curves, decision curve analysis (DCA), concordance index, and calibration curves demonstrated the discriminative superiority of the nomograms.

Conclusions

The nomograms, which effectively solve the issue of the survival paradox in the AJCC staging system regarding LARC, may act as excellent tools for integrating clinical characteristics and to guiding therapeutic choices for LARC patients.

Robotic vs laparoscopic right colectomy – the burden of age and comorbidity in perioperative outcomes: An observational study

BACKGROUND

Several studies have shown the safety, feasibility and oncologic adequacy of robotic right hemicolectomy (RRH). Laparoscopic right hemicolectomy (LRH) is considered technically challenging. Robotic surgery has been introduced to overcome this technical limitation, but it is related to high costs. To maximize the benefits of such surgery, only selected patients are candidates for this technique. In addition, due to progressive aging of the population, an increasing number of minimally invasive procedures are performed on elderly patients with severe comorbidities, who are usually more prone to post-operative complications.

AIM

To investigate the outcomes of RRH vs LRH with regard to age and comorbidities.

METHODS

We retrospectively analyzed 123 minimally invasive procedures (68 LRHs vs 55 RRHs) for right colon cancer or endoscopically unresectable adenoma performed in our Center from January 2014 until September 2019. The surgical procedures were performed according to standardized techniques. The primary clinical outcome of the study was the length of hospital stay (LOS) measured in days. Secondary outcomes were time to first flatus (TFF) and time to first stool evacuation. The robotic technique was considered the exposure and the laparoscopic technique was considered the control. Routine demographic variables were obtained, including age at time of surgery and gender. Body mass index and American Society of Anesthesiologists physical status were registered. The age-adjusted Charlson Comorbidity Index (ACCI) was calculated; the tumor-node-metastasis system, intra-operative variables and post-operative complications were recorded. Post-operative follow-up was 180 d.

RESULTS

LOS, TFF, and time to first stool were significantly shorter in the robotic group: Median 6 [interquartile range (IQR) 5-8] vs 7 (IQR 6-10.5) d, P = 0.028; median 2 (IQR 1-3) vs 3 (IQR 2-4) d, P < 0.001; median 4 (IQR 3-5) vs 5 (IQR 4-6.5) d, P = 0.005, respectively. Following multivariable analysis, the robotic technique was confirmed to be predictive of significantly shorter hospitalization and faster restoration of bowel function; in addition the dichotomous variables of age over 75 years and ACCI more than 7 were significant predictors of hospital stay. No outcomes were significantly associated with Clavien-Dindo grading. Sub-group analysis demonstrated that patients aged over 75 years had a longer LOS (median 6 -IQR 5-8- vs 7 -IQR 6-12- d, P = 0.013) and later TFF (median 2 -IQR 1-3- vs 3 -IQR 2-4- d, P = 0.008), while patients with ACCI more than 7 were only associated with a prolonged hospital stay (median 7 -IQR 5-8- vs 7 -IQR 6-14.5- d, P = 0.036).

CONCLUSION

RRH is related to shorter LOS when compared with the laparoscopic approach, but older age and several comorbidities tend to reduce its benefits.

Robotically Assisted Omentum Flap Harvest: A Novel, Minimally Invasive Approach for Vascularized Lymph Node Transfer

Background:

The omentum provides abundant lymphatic tissue with reliable vascular anatomy, representing an ideal donor for vascularized lymph node transfer without risk for donor site lymphedema. We describe a novel, robotically assisted approach for omental flap harvest.

Methods:

All patients undergoing robotically assisted omentum harvest for vascularized lymph node transfer from 2017 to 2019 were identified. Patient demographics, intraoperative variables, and postoperative outcomes were reviewed.

Results:

Five patients underwent robotically assisted omentum flap harvest for vascularized lymph node transfer. The average patient age and body mass index were 51.2 years and 29.80 kg/m², respectively. Indications for lymph node transfer were upper extremity lymphedema following mastectomy, radiation, and lymphadenectomy (60.0%); congenital unilateral lower extremity lymphedema (20.0%); and bilateral lower extremity/scrotal lymphedema following partial penectomy and bilateral inguinal/pelvic lymphadenectomy (20.0%). Four patients (80.0%) underwent standard robotic harvest, whereas 1 patient underwent single-port robotic harvest. The average number of port sites was 4.4. All patients underwent omentum flap transfer to 2 sites; in 2 cases, the flap was conjoined, and in 3 cases, the flap was segmented. The average overall operative time was 9:19. The average inpatient hospitalization was 5.2 days. Two patients experienced cellulitis, which is resolved with oral antibiotics. There were no major complications. All patients reported subjective improvement in swelling and softness of the affected extremity. The average follow-up was 8.8 months.

Conclusions:

Robotically assisted omental harvest for vascularized lymph node transfer is a novel, safe, and viable minimally invasive approach offering improved intra-abdominal visibility and maneuverability for flap dissection.

ZEB2-AS1 Accelerates Epithelial/Mesenchymal Transition Through miR-1205/CRKL Pathway in Colorectal Cancer

Background: Accumulating reports have demonstrated that long-noncoding RNAs (lncRNAs) play critical roles in the pathological progression of colorectal cancer (CRC). However, the role of lncRNA zinc finger E-box binding homeobox 2 antisense RNA 1 (ZEB2-AS1) in CRC remains largely unknown. Methods: The authors detected the ZEB2-AS1 expression in CRC tissue sample and CRC cell lines. The effects of ZEB2-AS1 on CRC were identified through in vitro assays (i.e., transwell assay, wound-healing assay, immunofluorescence assay, and Western blot) in a ZEB2-AS1 knockdown system. The molecular mechanism of ZEB2-AS1 was explored via bioinformatic tools, quantitative real-time polymerase chain reaction (qRT-PCR), dual-luciferase reporter assay, RNA immunoprecipitation assay, and so on. Moreover, a series of gain-of-function experiments were performed to identify the effect of ZEB2-AS1 and miR-1205 on epithelial-to-mesenchymal transition (EMT) in CRC cells. Results: This analysis clarified that ZEB2-AS1 was upregulated in both CRC tissue sample and cells lines; meanwhile, the high expression of ZEB2-AS1 was correlated with poor overall survival rate. ZEB2-AS1 knockdown significantly suppresses the EMT in CRC cells. Furthermore, the authors identified that the expression of ZEB2-AS1 was negatively correlated with expression of miR-1205, and CRKL could be a direct target of miR-1205. Through the gain-of-function experiments, they found that ZEB2-AS1 accelerates EMT in CRC cells via modulating the expression of miR-1205 and CRKL. Conclusion: Taken together, this study revealed that ZEB2-AS1 accelerates EMT in CRC through the miR-1205/CRKL pathway, suggesting that ZEB2-AS1 may potentially serve as a target of CRC.

The main contributor to the upswing of survival in locally advanced colorectal cancer: an analysis of the SEER database

BACKGROUND

There is no conclusion about the most important contributor to the upswing of locally advanced colorectal cancer (LACRC) survival.

METHODS

Data from the Surveillance, Epidemiology, and End Results (SEER) database was extracted to identify colorectal adenocarcinoma cancer patients at stage II and III diagnosed in the two periods 1989-1990 and 2009-2010. The statistical methods included Pearson's chi-squared test, log-rank test, Cox regression model and propensity score matching.

RESULTS

The Cox regression model showed that hazard ratio (HR) of non-surgery dropped from 11.529 to 3.469 in right colon cancer (RCC), 5.214 to 2.652 in left colon cancer (LCC) and 3.275 to 3.269 in rectal cancer (RC) from 1989-1990 to 2009-2010. The 95% confidence intervals (CIs) for surgical resection in 2009-2010 were narrower than those in 1989-1990. HR became greater in LACRC without chemotherapy (from 1.337 to 1.779 in RCC, 1.269 to 2.017 in LCC, 1.317 to 1.811 in RC). There was no overlapping about the 95% CI of chemotherapy between the two groups. The progress of surgery was not linked to the improvement of overall survival (OS) of RCC (p = 0.303) and RC (p = 0.660). Chemotherapy had a significant association with OS of all colorectal cancer (CRC) patients (p = 0.017 in RCC; p = 0.006 in LCC; p = 0.001 in RC).

CONCLUSIONS

Advancements in chemotherapy regimen were the main contributor to the upswing of CRC survival. The improvements in surgery had a limited effect on improvements in CRC survival.