The adoption of laparoscopic surgery in the management of serosa-exposed colorectal cancer has raised concerns. This study aimed to investigate whether laparoscopic surgery is associated with an ...increased risk of postoperative recurrence in patients undergoing resection for serosa-exposed colon cancer. A retrospective analysis was conducted on a cohort of 315 patients who underwent curative resection for pathologically confirmed T4a colon cancer without distant metastases at the Asan Medical Center between 2006 and 2015. Patients were categorized according to the surgical approach method: laparoscopic surgery (MIS group) versus open surgery (Open group). Multivariate analysis was employed to identify risk factors associated with overall survival (OS) and disease-free survival (DFS). The MIS group included 148 patients and the Open group had 167 patients. Of the total cohort, 106 patients (33.7%) experienced recurrence during the follow-up period. Rates, patterns, and time to recurrence were not different between groups. The MIS group (55.8%) showed more peritoneal metastasis compared to the Open group (44.4%) among recurrence sites, but it was not significant (p = 0.85). There was no significant difference in the five-year OS (73.5% vs. 78.4% p = 0.374) or DFS (62.0% vs. 64.6%; p = 0.61) between the Open and MIS groups. Age and the pathologic N stage were independently associated with OS, and the pathologic N stage was the only associated risk factor for DFS. The laparoscopic approach for serosa-exposed colon cancer did not compromise the DFS and OS. This study provides evidence that laparoscopic surgery does not compromise oncologic outcomes of patients with T4a colon cancer although peritoneal seeding is the most common type of disease failure of serosa-exposed colon cancer.
Watch and wait (WW) strategies have been suggested for patients with clinical complete regression (cCR). The WW approach was first introduced by Habr–Gama in patients with cCR after neoadjuvant ...treatment. Actually, it is not “no surgery” but “deferral of surgery;” therefore, the WW approach or non-operative management is a representative term currently. The number of publications regarding WW for rectal cancer has increased abruptly. We conducted a systematic review of PubMed for literature published on WW. It is now one of the most interesting issues in rectal cancer treatment. Many studies have reported comparable overall survival with WW and radical resection. However, a high local regrowth rate is a problem, and proper salvage management is the main concern in the WW approach. Adequate patient selection is necessary to achieve favorable oncologic outcomes. However, the appropriate definition and diagnostic method for cCR have not yet been clearly defined. Indeed, advances in local control have not translated into overall survival improvement, and many efforts have been made to improve distant metastasis control and overall survival and improve clinical response to preoperative chemoradiotherapy. In this review, oncologic outcomes, ongoing efforts to improve oncologic outcomes, and limitations for clinical practice were evaluated and described.
To evaluate the effective dose and patterns of recurrence after stereotactic body radiation therapy (SBRT) for hepatic metastases that arise from colorectal cancer.
A cohort of 70 patients with 103 ...colorectal liver metastases were treated with SBRT at a single institution. The prescribed doses were 45 to 60 Gy in 3 to 4 fractions, but these were modified according to the tolerance of the adjacent normal tissue. To allow for dose comparisons, a biological equivalent dose was calculated.
The median follow-up period was 34.2 months (range, 5.3-121.8 months). The 2-year overall survival and progression-free survival rates were 75% and 35%, respectively. In subgroups, the 2-year local control rates for biological equivalent dose ≤80 Gy (group 1), 100 to 112 Gy (group 2), and ≥132 Gy (group 3) were 52%, 83%, and 89%, respectively. Cox proportional hazards model revealed a significant difference between groups (hazard ratio 0.44, P=.03 for group 2; hazard ratio 0.17, P=.17 for group 3; P=.01 for total). The major pattern of failure was a new liver metastasis out of the SBRT field. There was no grade ≥3 toxicity.
Stereotactic body radiation therapy of liver metastases derived from colorectal cancer offers a locally effective treatment without significant complications. Longer local control can be expected if higher doses are used. Further studies will be needed to compare the efficacies of SBRT with those of surgical resection or radiofrequency ablation.
In patients with locally advanced rectal cancer,preoperative chemoradiotherapy has proven to significantly improve local control and cause lower treatmentrelated toxicity compared with postoperative ...adjuvant treatment.Preoperative chemoradiotherapy followed by total mesorectal excision or tumor specific mesorectal excision has evolved as the standard treatment for locally advanced rectal cancer.The paradigm shift from postoperative to preoperative therapy has raised a series of concerns however that have practical clinical implications.These include the method used to predict patients who will show good response,sphincter preservation,the application of conservative management such as local excision or"wait-and-watch"in patients obtaining a good response following preoperative chemoradiotherapy,and the role of adjuvant chemotherapy.This review addresses these current issues in patients with locally advanced rectal cancer treated by preoperative chemoradiotherapy.
Anatomical and physiological differences exist between sex, leading to variations in how diseases, such as rectal cancer, are prevalence and treatment outcomes of diseases including rectal cancer. In ...particular, in the case of rectal cancer, anatomical differences may be associated with surgical challenges, and these factors are believed to be important contributors to potential disparities in postoperative recovery, associated complications, and oncological outcomes between male and female patients. However, there is still ongoing debate regarding this matter. Significantly, the male pelvic anatomy is distinguished by its narrower dimensions, which can present surgical challenges and impede visual access during operative procedures, rendering it more complex than surgical interventions in the female pelvis. As a result, this anatomical difference leads to a greater occurrence of postoperative complications, such as anastomotic leakage. Moreover, the pelvis houses nerves that are vital for urinary and genital functions, underscoring the need to assess the potential risks of sexual and urinary dysfunction in rectal cancer surgery. These postoperative complications can significantly impact the quality of life; therefore, it is imperative to perform surgery with an understanding of the structural differences between sexes. Therefore, to address the limitations imposed by anatomical structures, new approaches such as robotic surgery, trans-anal total mesorectal excision, and intraoperative neuromonitoring are being introduced. Furthermore, it is essential to conduct research into fundamental mechanisms that may give rise to differences in surgical outcomes and oncological results between sexes. By comprehending the disparities between males and females, we can advance toward personalized treatments. Consequently, this review outlines variations in surgical approaches, complications, and treatments for rectal cancer in male and female patients.
Over the last several decades, plants have been developed as a platform for the production of useful recombinant proteins due to a number of advantages, including rapid production and scalability, ...the ability to produce unique glycoforms, and the intrinsic safety of food crops. The expression methods used to produce target proteins are divided into stable and transient systems depending on applications that use whole plants or minimally processed forms. In the early stages of research, stable expression systems were mostly used; however, in recent years, transient expression systems have been preferred. The production of the plant itself, which produces recombinant proteins, is currently divided into two major approaches, open-field cultivation and closed-indoor systems. The latter encompasses such regimes as greenhouses, vertical farming units, cell bioreactors, and hydroponic systems. Various aspects of each system will be discussed in this review, which focuses mainly on practical examples and commercially feasible approaches.
Neoadjuvant chemoradiotherapy for rectal cancer is associated with improved local control and may result in complete tumor response. Associations between tumor response and disease control following ...radical resection should be established before tumor response is used to evaluate treatment strategies. The purpose of this study was to assess and compare oncologic outcomes associated with the degree of pathologic response after chemoradiotherapy.
All patients with locally advanced (cT3-4 or cN+ by endorectal ultrasonography, computed tomography, or magnetic resonance imaging) rectal carcinoma diagnosed from 1993 to 2008 at our institution and treated with preoperative chemoradiotherapy and radical resection were identified, and their records were retrospectively reviewed. The median radiation dose was 50.4 Gy with concurrent chemotherapy. Recurrence-free survival (RFS), distant metastasis (DM), and local recurrence (LR) rates were compared among patients with complete (ypT0N0), intermediate (ypT1-2N0), or poor (ypT3-4 or N+) response by using Kaplan-Meier survival analysis and multivariate Cox proportional hazards regression.
In all, 725 patients were classified by tumor response: complete (131; 18.1%), intermediate (210; 29.0%), and poor (384; 53.0%). Age, sex, cN stage, and tumor location were not related to tumor response. Tumor response (complete v intermediate v poor) was associated with 5-year RFS (90.5% v 78.7% v 58.5%; P < .001), 5-year DM rates (7.0% v 10.1% v 26.5%; P < .001), and 5-year LR only rates (0% v 1.4% v 4.4%; P = .002).
Treatment response to neoadjuvant chemoradiotherapy among patients with locally advanced rectal cancer undergoing radical resection is an early surrogate marker and correlate to oncologic outcomes. These data provide guidance with response-stratified oncologic benchmarks for comparisons of novel treatment strategies.
PDF
