Byung Soh Min

Comparative study of resection and radiofrequency ablation in the treatment of solitary colorectal liver metastases

BACKGROUND We compared outcomes in patients with solitary colorectal liver metastases treated by either hepatic resection (HR) or radiofrequency ablation (RFA). METHODS A retrospective analysis from a prospective database was performed on 67 consecutive patients with solitary colorectal liver metastases treated by either HR or RFA. RESULTS Forty-two patients underwent HR and 25 patients underwent RFA. The 5-year overall and local recurrence-free survival rates after HR (50.1% and 89.7%, respectively) were higher than after RFA (25.5% and 69.7%, respectively) (P = .0263 and .028, respectively). In small tumors less than 3 cm (n = 38), the 5-year survival rates between HR and RFA were similar, including overall (56.1% vs 55.4%, P = .451) and local recurrence-free (95.7% vs 85.6%, P = .304) survival rates. On multivariate analysis, tumor size, metastases treatment, and primary node status were significant prognostic factors. CONCLUSIONS HR had better outcomes than RFA for recurrence and survival after treatment of solitary colorectal liver metastases. However, in tumors smaller than 3 cm, RFA can be recommended as an alternative treatment to patients who are not candidates for surgery because the liver metastases is poorly located anatomically, the functional hepatic reserve after a resection would be insufficient, the patients comorbidity inhibits a major surgery, or extrahepatic metastases are present.

The impact of robotic surgery for mid and low rectal cancer: a case-matched analysis of a 3-arm comparison--open, laparoscopic, and robotic surgery.

Objective:The objective of this study was to clarify the impact of robotic surgery (RS) in the management of mid and low rectal cancer in comparison with open surgery (OS) and laparoscopic surgery (LS). Background:The benefits of RS in the treatment of rectal cancer have not yet been clearly described. Methods:Using propensity scores for adjustment of sex, age, body mass index, tumor stage, and tumor height, a well-balanced cohort with 165 patients in each group, was created by matching each patient who underwent RS as the study group with one who underwent OS or LS as the control group (RS:OS = 1:1, RS:LS = 1:1 match). Pathological results, morbidity, perioperative recovery, and short-term oncological results were compared between the 3 groups. Results:In RS and LS, the time to first flatus and resumed soft diet and length of hospital stay were significantly shortened compared with OS. Robotic surgery showed better recovery outcomes than LS with regard to time to resumed soft diet and length of hospital stay. The visual analog scale was significantly lower in the RS than in the OS and LS from postoperative days 1 to 5. The voiding problem and circumferential resection margin involvement rate were significantly lower in the RS group than in the OS group. No significant difference in 2-year disease-free survival was observed among the 3 groups. Conclusions:Robotic surgery may be an effective tool in the effort to maximize the advantages of minimally invasive surgery in the management of mid to low rectal cancer.

Risk Factors for Anastomotic Leakage after Laparoscopic Intracorporeal Colorectal Anastomosis with a Double Stapling Technique

BACKGROUND Laparoscopic rectal transection carries the risk of anastomotic leakage because of its technical difficulty and long staple line with an inadequate cutting angle. Our objective was to investigate the risk factors affecting anastomotic leakage after laparoscopic intracorporeal colorectal anastomosis with a double stapling technique. STUDY DESIGN Between November 2006 and September 2008, 270 consecutive patients underwent laparoscopic sigmoidectomy and anterior resection with double stapling technique for distal sigmoid and rectal cancer. Data were collected prospectively. Univariate and multivariate analyses were performed to determine risk factors for anastomotic leakage. Additionally, we evaluated the relationship between the number of stapler firings and clinical parameters. RESULTS Anastomotic leakage was noted in 17 (6.3%) of 270 patients. In univariate analyses, tumor location (p = 0.021), operation time (p = 0.025), number of stapler firings (p = 0.040), and diameter of the circular stapler (p = 0.022) were significant risk factors for anastomotic leakage. Multivariate analyses showed that middle or lower rectal cancer was an independent factor affecting anastomotic leakage (p = 0.013). The number of stapler firings increased significantly in men (p = 0.023), in patients with a tumor at a lower level (p = 0.034), and in those with longer operation times (p < 0.001). CONCLUSIONS A reduction in the number of linear stapler firings is necessary to avoid anastomotic leakage after laparoscopic colorectal anastomosis with a double stapling technique. We recommend that a diverting ileostomy is mandatory in patients with middle and lower rectal cancer where multiple linear staplers were used.

Long-term oncologic outcomes of robotic low anterior resection for rectal cancer: a comparative study with laparoscopic surgery.

OBJECTIVE The aim of this study is to evaluate long-term oncologic outcomes of robotic surgery for rectal cancer compared with laparoscopic surgery at a single institution. BACKGROUND Robotic surgery is regarded as a new modality to surpass the technical limitations of conventional surgery. Short-term outcomes of robotic surgery for rectal cancer were acceptable in previous reports. However, evidence of long-term feasibility and oncologic safety is required. METHODS Between April 2006 and August 2011, 217 patients who underwent minimally invasive surgery for rectal cancer with stage I-III disease were enrolled prospectively (robot, n = 133; laparoscopy, n = 84). Median follow-up period was 58 months (range, 4-80 months). Perioperative clinicopathologic outcomes, morbidities, 5-year survival rates, prognostic factors, and cost were evaluated. RESULTS Perioperative clinicopathologic outcomes demonstrated no significant differences except for the conversion rate and length of hospital stay. The 5-year overall survival rate was 92.8% in robotic, and 93.5% in laparoscopic surgical procedures (P = 0.829). The 5-year disease-free survival rate was 81.9% and 78.7%, respectively (P = 0.547). Local recurrence was similar: 2.3% and 1.2% (P = 0.649). According to the univariate analysis, this type of surgical approach was not a prognostic factor for long-term survival. The patients mean payment for robotic surgery was approximately 2.34 times higher than laparoscopic surgery. CONCLUSIONS No significant differences were found in the 5-year overall, disease-free survival and local recurrence rates between robotic and laparoscopic surgical procedures. We concluded that robotic surgery for rectal cancer failed to offer any oncologic or clinical benefits as compared with laparoscopy despite an increased cost.

The Influence of the Number of Retrieved Lymph Nodes on Staging and Survival in Patients With Stage II and III Rectal Cancer Undergoing Tumor-Specific Mesorectal Excision

Objective:This study was designed to determine whether the number of lymph nodes retrieved influence staging and survival in patients with stage II and III rectal cancer that undergo tumor-specific mesorectal excision. Summary Background Data:The prognostic impact of the retrieved nodes has been emphasized in patients with colorectal cancer, but few studies have focused on patients with rectal cancer. Methods:A total of 900 patients who underwent tumor-specific mesorectal excision with curative intent and adjuvant chemoradiation therapy for stage II and III rectal cancer from January 1989 to December 2006 were analyzed. Results:Cancer-specific survival (CSS) of stage II patients with less than 15 nodes (25th percentile) was not different from stage III patients, but CSS was better in stage II patients with more than 15 nodes. When using cutoff values of the 25th and 50th percentiles (22 and 31 nodes), recurrence-free survival (RFS) was statistically different among subgroups of stage II and III patients. In multivariate analysis, stage II disease with less than 15 nodes retrieved was an adverse factor for CSS and RFS. In Kaplan-Meier survival analysis, using cutoff values, the difference for CSS was not significant with 22 and more nodes and the difference for RFS was not observed with 23 and more nodes. Conclusions:The number of lymph nodes retrieved is closely associated with survival and recurrence in patients with stage II rectal cancer and, for more accurate prognostic stratification, at least 22 and 23 nodes seem to be necessary, respectively, for CSS and for RFS.

Tumor Volume Changes Assessed by Three-Dimensional Magnetic Resonance Volumetry in Rectal Cancer Patients After Preoperative Chemoradiation: The Impact of the Volume Reduction Ratio on the Prediction of Pathologic Complete Response

PURPOSE The aim of this study was to determine the correlation between tumor volume changes assessed by three-dimensional (3D) magnetic resonance (MR) volumetry and the histopathologic tumor response in rectal cancer patients undergoing preoperative chemoradiation therapy (CRT). METHODS AND MATERIALS A total of 84 patients who underwent preoperative CRT followed by radical surgery were prospectively enrolled in the study. The post-treatment tumor volume and tumor volume reduction ratio (% decrease ratio), as shown by 3D MR volumetry, were compared with the histopathologic response, as shown by T and N downstaging and the tumor regression grade (TRG). RESULTS There were no significant differences in the post-treatment tumor volume and the volume reduction ratio shown by 3D MR volumetry with respect to T and N downstaging and the tumor regression grade. In a multivariate analysis, the tumor volume reduction ratio was not significantly associated with T and N downstaging. The volume reduction ratio (>75%, p = 0.01) and the pretreatment carcinoembryonic antigen level (< or =3 ng/ml, p = 0.01), but not the post-treatment volume shown by 3D MR (< or = 5 ml), were, however, significantly associated with an increased pathologic complete response rate. CONCLUSION More than 75% of the tumor volume reduction ratios were significantly associated with a high pathologic complete response rate. Therefore, limited treatment options such as local excision or simple observation might be considered after preoperative CRT in this patient population.

Macrophage Migration Inhibitory Factor May Be Used as an Early Diagnostic Marker in Colorectal Carcinomas

Recent genetic studies have identified many differentially expressed genes in colorectal carcinomas. For validation of up-regulated genes in colorectal carcinomas, we performed an enzyme-linked immunosorbent assay. Candidate markers were selected from gene expression data for 40 colorectal cancers and 35 matched normal mucosal samples. Based on intensive filtering, 9 genes were selected for the further evaluations. Among them, macrophage migration inhibitory factor (MIF), inhibin betaA, and chemokine ligand 10 were screened, and the results were compared with carcinoembryonic antigen (CEA) in serum samples of 129 patients with colon cancer and 53 healthy control subjects. We found that the serum MIF level was significantly increased in patients with colorectal cancer. Compared with CEA, MIF was more sensitive in early cancer detection (47.3% vs 29.5%). However, the specificity was not as high as that of CEA (90.6% vs 100.0%). Our findings indicate that MIF may be used as a diagnostic marker in colorectal carcinomas.

Cetuximab in combination with 5-fluorouracil, leucovorin and irinotecan as a neoadjuvant chemotherapy in patients with initially unresectable colorectal liver metastases

Background: The efficacy and safety of a combination of cetuximab, irinotecan, and 5-fluorouracil/leucovorin (FOLFIRI) in downsizing unresectable colorectal liver metastases was investigated. Patients and Methods: Patients with unresectable colorectal liver metastases with or without resectable extrahepatic metastasis were enrolled. 23 patients initially received 400 mg/m2 of cetuximab, followed by a weekly infusion of 250 mg/m2 and a biweekly dose of irinotecan (180 mg/m2), with 5-fluorouracil both by bolus (400 mg/m2) and by a 46-h infusion (total of 2,400 mg/m2) with leucovorin (400 mg/m2). Results: The overall response rate was 39.1% (n = 9; 95% confidence interval (CI): 17.6-60.7%). The most common grade 3-4 toxicities were skin reactions (30.4%) and diarrhea (26.1%). The rate of conversion to resectable liver metastases was 30.4% (n = 7; 95% CI: 10.1-50.8%). The factors found to be significantly associated with R0 resection were lower serum carcinoembryonic antigen levels after chemotherapy (p = 0.039), being chemonaive (p = 0.002), and showing a higher incidence of grade 3-4 skin toxicity (p = 0.011). Conclusions: Cetuximab with FOLFIRI may be an effective and safe treatment option for downsizing unresectable colorectal liver metastases.

Robotic Colorectal Surgery: A Systematic Review

Aim. Robotic colorectal surgery may be a way to overcome the limitations of laparoscopic surgery. It is an emerging field; so, we aim in this paper to provide a comprehensive and data analysis of the available literature on the use of robotic technology in colorectal surgery. Method. A comprehensive systematic search of electronic databases was completed for the period from 2000 to 2011. Studies reporting outcomes of robotic colorectal surgery were identified and analyzed. Results. 41 studies (21 case series, 2 case controls, 13 comparative studies 1 prospective comparative, 1 randomized trial, 3 retrospective analyses) were reviewed. A total of 1681 patients are included in this paper; all of them use Da Vinci except 2 who use Zeus. Short-term outcome has been evaluated with 0 mortality and191 total major and minor complications. Pathological results were not analyzed in all studies and only 20 out of 41 provide data about the pathological results. Conclusion. Robotic surgery is safe and feasible option in colorectal surgery and a promising field; however, further prospective randomized studies are required to better define its role.

Short and Long-Term Outcomes of Robotic versus Laparoscopic Total Mesorectal Excision for Rectal Cancer: A Case-Matched Retrospective Study

AbstractThe true benefits of robotic surgery are controversial, and whether robotic total mesorectal excision (R-TME) can be justified as a standard treatment for rectal cancer patients needs to be clarified. This case-matched study aimed to compare the postoperative complications and short- and long-term outcomes of R-TME and laparoscopic TME (L-TME) for rectal cancer.Among 1029 patients, we identified 278 rectal cancer patients who underwent R-TME. Propensity score matching was used to match this group with 278 patients who underwent L-TME.The mean follow-up period was similar between both groups (L-TME vs R-TME: 52.5 ± 17.1 vs 51.0 ± 13.1 months, P = 0.253), as were patient characteristics. The operation time was significantly longer in the R-TME group than in the L-TME group (361.6 ± 91.9  vs 272.4 ± 83.8 min; P < 0.001), whereas the conversion rate, length of hospital stay, and recovery of pain and bowel motility were similar between both groups. The rates of circumferential resection margin involvement and early complications were similar between both groups (L-TME vs R-TME: 4.7% vs 5.0%, P = 1.000; and 23.7% vs 25.9%, P = 0.624, respectively), as were the 5-year overall survival, disease-free survival, and local recurrence rates (93.1% vs 92.2%, P = 0.422; 79.6% vs 81.8%, P = 0.538; 3.9% vs 5.9%, P = 0.313, respectively).The oncologic quality, short- and long-term outcomes, and postoperative morbidity in the R-TME group were comparable with those in the L-TME group.