Dae Kyung Sohn

Bio: Dae Kyung Sohn is an academic researcher from National Cancer Research Institute. The author has contributed to research in topics: Colorectal cancer & Colonoscopy. The author has an hindex of 32, co-authored 161 publications receiving 4335 citations. Previous affiliations of Dae Kyung Sohn include Harvard University.

Open versus laparoscopic surgery for mid or low rectal cancer after neoadjuvant chemoradiotherapy (COREAN trial): short-term outcomes of an open-label randomised controlled trial.

Abstract: Summary Background The safety and short-term efficacy of laparoscopic surgery for rectal cancer after preoperative chemoradiotherapy has not been demonstrated. The aim of the randomised Comparison of Open versus laparoscopic surgery for mid and low REctal cancer After Neoadjuvant chemoradiotherapy (COREAN) trial was to compare open surgery with laparoscopic surgery for mid or low rectal cancer after neoadjuvant chemoradiotherapy. Methods Between April 4, 2006, and Aug 26, 2009, patients with cT3N0–2 mid or low rectal cancer without distant metastasis after preoperative chemoradiotherapy were enrolled at three tertiary-referral hospitals. Patients were randomised 1:1 to receive either open surgery (n=170) or laparoscopic surgery (n=170), stratified according to sex and preoperative chemotherapy regimen. Short-term outcomes assessed were involvement of the circumferential resection margin, macroscopic quality of the total mesorectal excision specimen, number of harvested lymph nodes, recovery of bowel function, perioperative morbidity, postoperative pain, and quality of life. Analyses were based on the intention-to-treat population. Patients continue to be followed up for the primary outcome (3-year disease-free survival). This study is registered with ClinicalTrials.gov, number NCT00470951. Findings Two patients (1·2%) in the laparoscopic group were converted to open surgery, but were included in the laparoscopic group for analyses. Estimated blood loss was less in the laparoscopic group than in the open group (median 217·5 mL [150·0–400·0] in the open group vs 200·0 mL [100·0–300·0] in the laparoscopic group, p=0·006), although surgery time was longer in the laparoscopic group (mean 244·9 min [SD 75·4] vs 197·0 min [62·9], p vs 60·0 h [43·0–73·0], p vs 93·0 h [86·0–121·0], p vs 123 h [94·0–156·0], p vs 156·9 mg [117·0–185·2], p vs −4·970 [n=128], p=0·0073), less fatigue (−5·659 [n=122] vs 0·098 [n=129], p=0·0206), and fewer micturition (−2·583 [n=122] vs 4·725 [n=129], p=0·0002), gastrointestinal (−0·400 [n=122] vs 4·331 [n=129], p=0·0102), and defecation problems (0·535 [n=103] vs 5·327 [n=99], p=0·0184) in repeated measures analysis of covariance, adjusted for baseline values. Interpretation Laparoscopic surgery after preoperative chemoradiotherapy for mid or low rectal cancer is safe and has short-term benefits compared with open surgery; the quality of oncological resection was equivalent. Funding The National Cancer Center, South Korea.

Open versus laparoscopic surgery for mid-rectal or low-rectal cancer after neoadjuvant chemoradiotherapy (COREAN trial): survival outcomes of an open-label, non-inferiority, randomised controlled trial.

Abstract: Summary Background Compared with open resection, laparoscopic resection of rectal cancers is associated with improved short-term outcomes, but high-level evidence showing similar long-term outcomes is scarce. We aimed to compare survival outcomes of laparoscopic surgery with open surgery for patients with mid-rectal or low-rectal cancer. Methods The Comparison of Open versus laparoscopic surgery for mid or low REctal cancer After Neoadjuvant chemoradiotherapy (COREAN) trial was an open-label, non-inferiority, randomised controlled trial done between April 4, 2006, and Aug 26, 2009, at three centres in Korea. Patients (aged 18–80 years) with cT3N0–2M0 mid-rectal or low-rectal cancer who had received preoperative chemoradiotherapy were randomly assigned (1:1) to receive either open or laparoscopic surgery. Randomisation was stratified by sex and preoperative chemotherapy regimen. Investigators were masked to the randomisation sequence; patients and clinicians were not masked to the treatment assignments. The primary endpoint was 3 year disease-free survival, with a non-inferiority margin of 15%. Analysis was by intention to treat. This trial is registered with ClinicalTrials.gov, number NCT00470951. Findings We randomly assigned 340 patients to receive either open surgery (n=170) or laparoscopic surgery (n=170). 3 year disease-free survival was 72·5% (95% CI 65·0–78·6) for the open surgery group and 79·2% (72·3–84·6) for the laparoscopic surgery group, with a difference that was lower than the prespecified non-inferiority margin (–6·7%, 95% CI −15·8 to 2·4; p Interpretation Our results show that laparoscopic resection for locally advanced rectal cancer after preoperative chemoradiotherapy provides similar outcomes for disease-free survival as open resection, thus justifying its use. Funding National Cancer Center, South Korea.

Robot-assisted Versus Laparoscopic Surgery for Rectal Cancer: A Phase II Open Label Prospective Randomized Controlled Trial.

Abstract: Objective:The phase II randomized controlled trial aimed to compare the outcomes of robot-assisted surgery with those of laparoscopic surgery in the patients with rectal cancerBackground:The feasibility of robot-assisted surgery over laparoscopic surgery for rectal cancer has not been established y

Microarray gene expression profiling for predicting complete response to preoperative chemoradiotherapy in patients with advanced rectal cancer

Abstract: Preoperative chemoradiotherapy is widely used to improve local control and sphincter preservation in patients with locally advanced rectal cancer. In the present study, we investigated whether microarray gene expression analysis could predict complete response to preoperative chemoradiotherapy in rectal cancer. Tumor tissues were obtained from 46 patients with rectal cancer (31 for training and 15 for validation testing). All patients underwent preoperative chemoradiotherapy involving 50.4 gray radiotherapy, followed by surgical excision 6 weeks later. Response to chemoradiotherapy was evaluated according to Dworak’s tumor regression grade. Tumor regression Grades 1, 2, and 3 were considered partial responses, and tumor regression Grade 4 was considered a complete response. By using the 31 training samples, genes differentially expressed between partial response and complete response were identified, and clustering analysis was performed. Prediction analysis of response to chemoradiotherapy was performed on the 31 training samples by using a selected set of 95 “predictor” genes. Those findings were validated by independent analysis of the 15 test samples. The 31 training samples comprised 20 partial response and 11 complete response cases. A primary set of 261 genes was identified as differentiating between partial response and complete response. By supervised clustering using these 261 genes, 30 of 31 training samples were clustered correctly according to tumor response. A gene set comprising the top-ranked 95 genes displaying differential expression between partial response and complete response was applied to predict response to chemoradiotherapy. Complete response and partial response were accurately predicted in 84 percent (26/31) of training samples and 87 percent (13/15) of validation samples. Microarray gene expression analysis was successfully used to predict complete responses to preoperative chemoradiotherapy in patients with advanced rectal cancer.

Computed tomography-based high-dose-rate intracavitary brachytherapy for uterine cervical cancer: preliminary demonstration of correlation between dose-volume parameters and rectal mucosal changes observed by flexible sigmoidoscopy.

Abstract: Purpose: To compare the dose–volume histogram (DVH) parameters obtained by three-dimensional gynecologic brachytherapy planning with the rectosigmoid mucosal changes observed by flexible sigmoidoscopy. Methods and Materials: Between January 2004 and July 2005, 71 patients with International Federation of Gynecology and Obstetrics Stage IB–IIIB uterine cervical cancer underwent computed tomography-based high-dose-rate intracavitary brachytherapy. The total dose (external beam radiotherapy [RT] plus intracavitary brachytherapy) to the International Commission of Radiation Units and Measurements rectal point (ICRU RP ) and DVH parameters for rectosigmoid colon were calculated using the equivalent dose in 2-Gy fractions (α/β = 3 Gy). Sigmoidoscopy was performed every 6 months after RT, with the 6-scale scoring system used to determine mucosal changes. Results: The mean values of the DVH parameters and ICRU RP were significantly greater in patients with a score of ≥2 than in those with a score RP , 71 Gy α/β3 vs. 66 Gy α/β3 , p = 0.02; D 0.1cc , 93 Gy α/β3 vs. 85 Gy α/β3 , p = 0.04; D 1cc , 80 Gy α/β3 vs. 73 Gy α/β3 , p = 0.02; D 2cc , 75 Gy α/β3 vs. 69 Gy α/β3 , p = 0.02). The probability of a score of ≥2 showed a significant relationship with the DVH parameters and ICRU RP (ICRU RP , p = 0.03; D 0.1cc , p = 0.05; D 1cc , p = 0.02; D 2cc , p = 0.02). Conclusion: Our preliminary data have shown that DVH values of the rectosigmoid colon obtained by computed tomography-based three-dimensional brachytherapy planning are reliable and predictive of score ≥2 rectosigmoid mucosal changes.

Guidelines for perioperative care in elective colonic surgery: Enhanced recovery after surgery (ERAS®) society recommendations

Abstract: This is the fourth updated Enhanced Recovery After Surgery (ERAS®) Society guideline presenting a consensus for optimal perioperative care in colorectal surgery and providing graded recommendations for each ERAS item within the ERAS® protocol. A wide database search on English literature publications was performed. Studies on each item within the protocol were selected with particular attention paid to meta-analyses, randomised controlled trials and large prospective cohorts and examined, reviewed and graded according to Grading of Recommendations, Assessment, Development and Evaluation (GRADE) system. All recommendations on ERAS® protocol items are based on best available evidence; good-quality trials; meta-analyses of good-quality trials; or large cohort studies. The level of evidence for the use of each item is presented accordingly. The evidence base and recommendation for items within the multimodal perioperative care pathway are presented by the ERAS® Society in this comprehensive consensus review.

Clinical practice guidelines in oncology

Abstract: Ductal carcinoma in situ (DCIS) of the breast represents a heterogeneous group of neoplastic lesions in the breast ducts. The goal for management of DCIS is to prevent the development of invasive breast cancer. This manuscript focuses on the NCCN Guidelines Panel recommendations for the workup, primary treatment, risk reduction strategies, and surveillance specific to DCIS.

Laparoscopic versus open surgery for rectal cancer (COLOR II): short-term outcomes of a randomised, phase 3 trial

Abstract: Summary Background Laparoscopic surgery as an alternative to open surgery in patients with rectal cancer has not yet been shown to be oncologically safe. The aim in the COlorectal cancer Laparoscopic or Open Resection (COLOR II) trial was to compare laparoscopic and open surgery in patients with rectal cancer. Methods A non-inferiority phase 3 trial was undertaken at 30 centres and hospitals in eight countries. Patients (aged ≥18 years) with rectal cancer within 15 cm from the anal verge without evidence of distant metastases were randomly assigned to either laparoscopic or open surgery in a 2:1 ratio, stratified by centre, location of tumour, and preoperative radiotherapy. The study was not masked. Secondary (short-term) outcomes—including operative findings, complications, mortality, and results at pathological examination—are reported here. Analysis was by modified intention to treat, excluding those patients with post-randomisation exclusion criteria and for whom data were not available. This study is registered with ClinicalTrials.gov, number NCT00297791. Findings The study was undertaken between Jan 20, 2004, and May 4, 2010. 1103 patients were randomly assigned to the laparoscopic (n=739) and open surgery groups (n=364), and 1044 were eligible for analyses (699 and 345, respectively). Patients in the laparoscopic surgery group lost less blood than did those in the open surgery group (median 200 mL [IQR 100–400] vs 400 mL [200–700], p vs 188 min [150–240]; p vs 3·0 days [2·0–4·0]; p vs 9·0 days [7·0–14·0]; p=0·036). Macroscopically, completeness of the resection was not different between groups (589 [88%] of 666 vs 303 [92%] of 331; p=0·250). Positive circumferential resection margin ( vs 3·0 cm [1·8–5·0], respectively; p=0·676). In the laparoscopic and open surgery groups, morbidity (278 [40%] of 697 vs 128 [37%] of 345, respectively; p=0·424) and mortality (eight [1%] of 699 vs six [2%] of 345, respectively; p=0·409) within 28 days after surgery were similar. Interpretation In selected patients with rectal cancer treated by skilled surgeons, laparoscopic surgery resulted in similar safety, resection margins, and completeness of resection to that of open surgery, and recovery was improved after laparoscopic surgery. Results for the primary endpoint—locoregional recurrence—are expected by the end of 2013. Funding Ethicon Endo-Surgery Europe, Swedish Cancer Foundation, West Gothia Region, Sahlgrenska University Hospital.

A Randomized Trial of Laparoscopic versus Open Surgery for Rectal Cancer

Abstract: Background Laparoscopic resection of colorectal cancer is widely used. However, robust evidence to conclude that laparoscopic surgery and open surgery have similar outcomes in rectal cancer is lacking. A trial was designed to compare 3-year rates of cancer recurrence in the pelvic or perineal area (locoregional recurrence) and survival after laparoscopic and open resection of rectal cancer. Methods In this international trial conducted in 30 hospitals, we randomly assigned patients with a solitary adenocarcinoma of the rectum within 15 cm of the anal verge, not invading adjacent tissues, and without distant metastases to undergo either laparoscopic or open surgery in a 2:1 ratio. The primary end point was locoregional recurrence 3 years after the index surgery. Secondary end points included disease-free and overall survival. Results A total of 1044 patients were included (699 in the laparoscopic-surgery group and 345 in the open-surgery group). At 3 years, the locoregional recurrence rate was 5.0% in the ...