On the basis of the above results, the postoperative course of the ES group was similar to that of the BS group. In addition, the long-term oncologic outcome of the BS group was similar or slightly better than that of the ES group. BS after colonic stent may be an alternative option for MORC.

A bridge to surgery (BtS) after a colonic stent for obstructive colon cancer has not been accepted as a standard treatment strategy. Also, there is no consensus regarding the optimal time interval for BtS. We aimed to identify the optimal timing for BtS after stent placement to decrease the oncologic risk. We retrospectively collected data of 174 patients who underwent BTS after stent placement for stage II or III obstructive colon cancer from five hospitals. We divided the patients into three groups based on the time interval for BTS after stent placement: within 7 days (Group 1), from 8 to 14 days (Group 2), and after 14 days (Group 3). The primary outcome was to compare the oncologic outcomes including overall survival (OS), disease-free survival (DFS), and recurrence rate (RR) among the three groups. Groups 1, 2, and 3 involved 75, 56, and 43 patients, respectively. Postoperative morbidity rates were 17.3%, 10.8%, and 9.3% in Groups 1, 2, and 3, respectively (P = 0.337). RRs were 16.0%, 35.7%, and 30.2% in Groups 1, 2, and 3, respectively (P = 0.029). In multivariate analysis, the time interval for BTS was an independent risk factor for DfS (p < 0.001; HR, 14.463; 95% CI, 1.458-3.255) and OS (P = 0.027; HR, 4.917; 95% CI, 1.071-3.059). In conclusion, the perioperative short-term outcome was not affected by the time interval of BTS. However, elective surgery within 7 days after colonic stent might be suggested to balance the short-term benefits and long-term oncologic risks. About 8-29% of patients with colorectal cancer (CRC) are presented with symptoms of a malignant obstruction at the time of diagnosis, and 85% of emergency colorectal surgery result from obstructive symptoms 1-3. There are several therapeutic options in treating obstructing CRC, including single-stage radical colectomy which means colectomy with en bloc removal of regional lymph node and primary anastomosis are performed simultaneously, resection of primary lesion with diversion, or bridge to surgery (BTS) after diversion or stent. Colonic stent using self-expandable metal stent (SEMS) placement to an obstructive lesion can make a BTS possible therapeutic option by converting an emergency situation into an elective one in patients with operable obstructing cancer 4. Compared with emergency surgery, SEMS placement as BTS may have some advantages: less morbidity rate, increased primary anastomosis rate, and decreased permanent stoma rate 5. However, in long-term outcomes, the use of SEMS as a BTS may be related to an increased risk of colorectal cancer recurrences 6-8. According to the European Society of Gastrointestinal Endoscopy (ESGE) Clinical Guideline, SEMS placement for BTS is not recommended as a standard treatment of symptomatic cancer obstruction in left-sided colon and may be acceptable as an alternative to emergency surgery in a group of patients at high risk of postoperative mortality 9 .

Background. Volumetric modulated arc therapy (VMAT) with simultaneous integrated boost (SIB) is an advanced form of radiotherapy (RT) technology. The purpose of this study was to report long-term treatment outcomes in patients with locally advanced rectal cancer undergoing VMAT-SIB based concurrent chemoradiotherapy (CRT). Methods. Between January 2016 and January 2018, a total of 22 patients with operable stage II-III rectal adenocarcinoma were recruited for the pre-designed VMAT-SIB RT protocol. All patients underwent standard diagnostic and staging work-up. The RT target volumes included the following areas: PTV1 = mesorectum that contained gross tumors and enlarged lymph node regions and PTV2 = mesorectum and regional lymphatics from L4-5/S1 to 3-4 cm below the tumor or levator ani muscle, excluding PTV1. The VMAT-SIB dose prescription was as follows: PTV1 = 52.5 Gy/daily 2.1 Gy/25 fractions, PTV2 = 45 Gy/daily 1.8 Gy/25 fractions. Results. The mean age of the study population was 64 (range, 18-84) years, and 15 (68.2%) patients were male. Radical operation (total mesorectal excision) was performed by either low anterior resection, ultralow anterior resection, or abdominal perineal resection. All five (22.7%) of the patients with confirmed increasing serum carcinoembryonic antigen (CEA) level at diagnosis showed normalization of serum CEA level after the planned treatment. Among 20 patients who underwent preoperative CRT and surgery, tumor down staging in T- and N-stages was achieved in 10 patients (50%) and 13 patients (65%), respectively, with 20% of ypT0/Tis. With a median follow-up of 54.2 (range, 22.6-61.1) months, the 5-year disease-free survival, overall survival, and local control rates were 64.6%, 81.8%, and 84.4%, respectively. Five patients developed distant metastasis and one developed local recurrence as a first event. Two cases with anastomosis site leakage, three with adhesive ileus, and two with abscess formation were observed during postoperative periods. Conclusions. The current VMAT-SIB-based CRT protocol provided acceptable treatment and toxicity outcomes.