Implementable assay for monitoring minimum residual disease after radical treatment for colorectal cancer.

Considering the cost and invasiveness of monitoring postoperative minimal residual disease (MRD) of colorectal cancer (CRC) after adjuvant chemoradiotherapy (ACT), we developed a favorable approach based on methylated circulating tumor DNA to detect MRD after radical resection. Analyzing the public database, we identified the methylated promoter regions of the genes FGD5, GPC6, and MSC. Using digital polymerase chain reaction (dPCR), we termed the "amplicon of methylated sites using a specific enzyme" assay as "AMUSE." We examined 180 and 114 pre- and postoperative serial plasma samples from 28 recurrent and 19 recurrence-free pathological stage III CRC patients, respectively. The results showed 22 AMUSE-positive of 28 recurrent patients (sensitivity, 78.6%) and 17 AMUSE-negative of 19 recurrence-free patients (specificity, 89.5%). AMUSE predicted recurrence 208 days before conventional diagnosis using radiological imaging. Regarding ACT evaluation by the reactive response, 19 AMUSE-positive patients during their second or third blood samples showed a significantly poorer prognosis than the other patients (p = 9E-04). The AMUSE assay stratified four groups by the altered patterns of tumor burden postoperatively. Interestingly, only 34.8% of cases tested AMUSE-negative during ACT treatment, indicating eligibility for ACT. The AMUSE assay addresses the clinical need for accurate MRD monitoring with universal applicability, minimal invasiveness, and cost-effectiveness, thereby enabling the timely detection of recurrences. This assay can effectively evaluate the efficacy of ACT in patients with stage III CRC following curative resection. Our study strongly recommends reevaluating the clinical application of ACT using the AMUSE assay.

Long-term survival and functional outcomes of laparoscopic surgery for clinical stage I ultra-low rectal cancers located within 5 cm of the anal verge: A prospective phase II trial (Ultimate trial).

OBJECTIVE: To clarify the long-term oncological outcomes and postoperative anal, urinary, and sexual functions after laparoscopic surgery for clinical stage I very low rectal carcinoma located near the anal canal. SUMMARY BACKGROUND DATA: Laparoscopic surgery is widely applied for rectal cancer; however, concerns remain, with some studies showing poorer outcomes compared to open surgery. METHODS: This single-arm, phase II trial included patients registered preoperatively from 47 institutions in Japan. The planned sample size was 300. The primary endpoint was the 3-year local recurrence rate. Anal, urinary, and sexual functions were evaluated using a prospective questionnaire. RESULTS: Three-hundred patients were registered between January 2014 and March 2017. Anus-preserving surgery was performed in 278 (93%), including 172 who underwent intersphincteric resection (58%) and 106 (36%) who underwent low anterior resection. The 3-year cumulative local recurrence rate was 6.3%. At 3 years postoperatively, 87% of patients used their own anus, and the median incontinence score improved from 12 at 3 months to 8 at 3 years. Only 5% of patients had severe incontinence (incontinence score of 16 points). Postoperative urinary function evaluation showed that International Prostate Symptom Score and Overactive Bladder Symptom Score decreased 1 week after surgery, but recovered to preoperative level 1 month after surgery. International Consultation on Incontinence Questionnaire-Sort Form remained almost stable after surgery. Sexual function evaluation using the International Index of Erectile Function-5 and International Index of Erectile Function-15 revealed that the patients had deteriorated 3 months after surgery but had recovered only slightly by 6 months. CONCLUSIONS: Laparoscopic surgery achieves feasible long-term oncological outcomes and a high rate of anus preservation with moderate anal function, and an acceptable incontinence score. While urinary function recovered rapidly, sexual function showed poor recovery.

How Does Omitting Additional Surgery After Local Excision Affect the Prognostic Outcome of Patients With High-risk T1 Colorectal Cancer?

OBJECTIVE: To investigate how omitting additional surgery after local excision (LE) affects patient outcomes in high-risk T1 colorectal cancer (CRC). BACKGROUND: It is debatable whether additional surgery should be performed for all patients with high-risk T1 CRC regardless of the tolerability of invasive procedures. METHODS: Patients who had received LE for T1 CRC at the Japanese Society for Cancer of the Colon and Rectum institutions between 2009 and 2016 were analyzed. Those who had received additional surgical resection and those who did not were matched one-on-one by the propensity score-matching method. A total of 401 propensity score-matched pairs were extracted from 1975 patients at 27 Japanese Society for Cancer of the Colon and Rectum institutions and were compared. RESULTS: Regional lymph node metastasis was observed in 31 (7.7%) patients in the LE + surgery group. Comparatively, the incidence of oncologic adverse events was low in the LE-alone group, such as the 5-year cumulative risk of local recurrence (4.1%) or overall recurrence (5.5%). In addition, the difference in the 5-year cancer-specific survival between the LE + surgery and LE-alone groups was only 1.8% (99.7% and 97.9%, respectively), whereas the 5-year overall survival was significantly lower in the LE-alone group than in the LE + surgery group [88.5% vs 94.5%, respectively ( P = 0.002)]. CONCLUSIONS: Those who had decided to omit additional surgery at the dedicated center for CRC treatment presented a small number of oncologic events and a satisfactory cancer-specific survival, which may suggest an important role of risk assessment regarding nononcologic adverse events to achieve a best practice for each individual with high-risk T1 tumors.

Long-term outcomes of additional surgery after endoscopic resection versus primary surgery for T1 colorectal cancer.

INTRODUCTION: There is considerable concern about whether endoscopic resection (ER) prior to additional surgery (AS) for T1 colorectal cancer (CRC) has oncologically potential adverse effects. Therefore, this study aimed to compare the long-term outcomes, including overall survival (OS), of patients treated with AS after ER versus primary surgery (PS) for T1 CRC using a propensity score-matched analysis from a large observational study. METHODS: This study investigated 6105 patients with T1 CRC treated with either ER or surgical resection between 2009 and 2016 at 27 high-volume Japanese institutions, with those undergoing surgery alone included in the PS group and those undergoing AS after ER included in the AS group. Propensity score matching was used for long-term outcomes of mortality and recurrence analysis. RESULTS: After propensity score matching, 1219 of 2438 patients were identified in each group. The 5-year OS rates in the AS and PS groups were 97.1% and 96.0%, respectively (hazard ratio: 0.72, 95% confidence interval [CI]: 0.49-1.08), indicating the non-inferiority of the AS group. Moreover, 32 patients (2.6%) in the AS group and 24 (2.0%) in the PS group had recurrences, with no significant difference between the two groups (odds ratio: 1.34, 95% CI: 0.76-2.40, p = 0.344). DISCUSSION: ER prior to AS for T1 CRC had no adverse effect on patients' long-term outcomes, including the 5-year OS rate. ER is a viable first-line treatment option for endoscopically resectable T1 CRC.

Treatment Decision for Locally Resected T1 Colorectal Carcinoma-Verification of the Japanese Guideline Criteria for Additional Surgery Based on Long-Term Clinical Outcomes.

INTRODUCTION: To verify the value of the pathological criteria for additional treatment in locally resected pT1 colorectal carcinoma (CRC) which have been used in the Japanese Society for Cancer of the Colon and Rectum (JSCCR) guidelines since 2009. METHODS: We enrolled 4,719 patients with pT1 CRC treated at 27 institutions between July 2009 and December 2016 (1,259 patients with local resection alone [group A], 1,508 patients with additional surgery after local resection [group B], and 1,952 patients with surgery alone [group C]). All 5 factors of the JSCCR guidelines (submucosal resection margin, tumor histologic grade, submucosal invasion depth, lymphovascular invasion, and tumor budding) for lymph node metastasis (LNM) had been diagnosed prospectively. RESULTS: Any of the risk factors were present in 3,801 patients. The LNM incidence was 10.3% (95% confidence interval 9.3-11.4) in group B/C patients with risk factors, whereas it was 1.8% (95% confidence interval 0.4-5.2) in those without risk factors ( P < 0.01). In group A, the incidence of recurrence was 3.4% in patients with risk factors, but it was only 0.1% in patients without risk factors ( P < 0.01). The disease-free survival rate of group A patients classified as risk positive was significantly worse than those of groups B and C patients. However, the 5-year disease-free survival rate in group A patients with no risk was 99.2%. DISCUSSION: Our large-scale real-world multicenter study demonstrated the validity of the JSCCR criteria for pT1 CRC after local resection, especially regarding favorable outcomes in patients with low risk of LNM.

The impact of staple transection of the dorsal venous complex and urethra on intraoperative blood loss in cooperative laparoscopic and transperineal endoscopic pelvic exenteration.

PURPOSE: While laparoscopic pelvic exenteration reduces intraoperative blood loss, dorsal venous complex bleeding during this procedure causes issues. We previously introduced a method to transect the dorsal venous complex and urethra using a linear stapler during cooperative laparoscopic and transperineal endoscopic (two-team) pelvic exenteration. The present study assessed its effectiveness in reducing intraoperative blood loss by comparing it with conventional laparoscopic pelvic exenteration. METHODS: This retrospective cohort study was conducted at a Japanese tertiary referral center. Eleven cases of two-team laparoscopic pelvic exenteration with staple transection of the dorsal venous complex (T-PE group) were compared to 25 cases of conventional laparoscopic pelvic exenteration (C-PE group). The primary outcome measure was intraoperative blood loss. RESULTS: There were no significant between-group differences in patient background. The mean intraoperative blood loss was significantly lower in the T-PE group than in the C-PE group (200 vs. 850 mL, p = 0.01). The respective mean operation time, postoperative complication rate, and R0 resection rate were similar between the T-PE and C-PE groups (636 min vs. 688 min, p = 0.36; 36% vs. 44%, p = 0.65; 100% vs. 100%, p = 1.00). CONCLUSIONS: Two-team laparoscopic pelvic exenteration with staple transection of the dorsal venous complex reduced intraoperative blood loss from the dorsal venous complex in a technically safe and oncologically feasible manner.

Incidence and risk factors of bowel dysfunction after minimally invasive rectal cancer surgery and discrepancies between the Wexner score and the low anterior resection syndrome (LARS) score.

PURPOSE: Bowel dysfunction after sphincter-preserving-surgery (SPS) impacts quality of life. The Wexner score (WS) and the low anterior resection syndrome (LARS) score (LS) are instruments for assessing postoperative bowel dysfunction. We analyzed the incidence of and risk factors for each symptom and examined the discrepancies between the two scores. METHODS: A total of 142 patients with rectal cancer, who underwent minimally invasive SPS between May, 2018 and July, 2019, were included. A questionnaire survey using the two scores was given to the patients 2 years after SPS. RESULTS: Tumor location and preoperative radiotherapy were independent risk factors for major LARS. Intersphincteric resection with a hand-sewn anastomosis (HSA) was an independent risk factor for high WS. Among the patients who underwent HSA, 82% experienced incontinence for liquid stools, needed to wear pads, and suffered lifestyle alterations. Of the 35 patients with minor LARS, only 1 had a high WS, and 80.0% reported no lifestyle alterations. Among the 75 patients with major LARS, 58.7% had a low WS and 21.3% reported no lifestyle alterations. CONCLUSION: The results of this study provide practical data to help patients understand potential bowel dysfunction after SPS. The discrepancies between the WS and LS were clarified, and further efforts are required to utilize these scores in clinical practice.

Clinical utility of the carcinoembryonic antigen level in patients with stage III colon cancer after surgery and adjuvant chemotherapy.

PURPOSE: The association between perioperative and post-adjuvant carcinoembryonic antigen (CEA) levels and recurrence and prognosis remains unclear. We aimed to evaluate whether perioperative CEA levels are an integral component of the assessment of recurrence and prognosis of patients with stage III colon cancer (CC). METHODS: This retrospective study was conducted at the Cancer Institute Hospital of the Japanese Foundation for Cancer Research from 2005 to 2013. We enrolled patients with stage III CC who underwent complete resection of a primary tumor and received adjuvant chemotherapy. We analyzed the association between perioperative and post-adjuvant CEA levels and recurrence-free survival (RFS) and overall survival (OS). RESULTS: A total of 564 consecutive patients were included in the analysis. The RFS and OS of patients with high postoperative CEA levels were significantly worse than those of patients with normal postoperative CEA levels. In the multivariate analysis, high postoperative CEA levels were associated with shorter RFS and OS. The number of risk factors, postoperative CEA levels, and T/N-stage all had a cumulative effect on RFS and OS. CONCLUSIONS: High postoperative CEA levels and the number of risk factors are associated with recurrence and worse prognosis for patients with stage III CC.

Prognostic factors of para-aortic lymph node metastasis from colorectal cancer in highly selected patients undergoing para-aortic lymph node dissection.

PURPOSE: We investigated the surgical outcomes of para-aortic lymph node (PALN) dissection in patients with colorectal cancer and assessed the prognostic factors related to the survival. METHODS: This single-center retrospective study included 31 patients with synchronous or metachronous PALN metastasis from colorectal cancer who underwent PALN dissection between January 2006 and December 2018. RESULTS: Twenty-one patients had synchronous PALN metastasis, and 10 had metachronous PALN metastasis. Seven patients had either simultaneous distant metastasis or a history of distant metastasis other than PALN metastasis at the time of PALN dissection. Eighteen patients underwent adjuvant chemotherapy. The 5-year overall and recurrence-free survival rates were 54.2 and 17.2%, respectively. A multivariable analysis revealed that rectal cancer, metachronous PALN metastasis, and three or more pathological PALN metastases were significantly poor prognostic factors for the recurrence-free survival. Among patients with rectal cancer, lower rectal cancer and lateral pelvic lymph node metastasis were poor prognostic factors for the overall survival. CONCLUSION: Curative PALN dissection for PALN metastasis from colorectal cancer is feasible with favorable long-term outcomes. A multidisciplinary approach, including surgery and chemotherapy, is needed for colorectal cancer with PALN metastasis to improve the long-term outcomes.

Risk Factors for Lymph Node Metastasis of Rectal Neuroendocrine Tumor and Its Prognostic Impact: A Single-Center Retrospective Analysis of 195 Cases with Radical Resection.

PURPOSE: The incidence of rectal neuroendocrine tumors (NETs) has been steadily increasing. The risk factors for and prognostic impact of lymph node (LN) metastasis were analyzed in 195 patients with stage I-III rectal NET who underwent radical surgery. METHODS: This retrospective, single-center study analyzed risk factors for LN metastasis focusing on previously identified factors and a novel risk factor: multiple rectal NETs. The association between LN metastasis and the prognosis was also analyzed. RESULTS: Pathologically, the LN metastasis rate (also the rate of stage III disease) was 39%, which was higher than the clinical LN metastasis rate of 14%. Tumor size > 10 mm, presence of central depression, tumor grade G2, depth of invasion, LN swelling on preoperative imaging (cN1), venous invasion and multiple NETs were identified as risk factors for LN metastasis. As the tumor size and risk factors increased, the rate of LN metastasis increased. Among these 7 factors, venous invasion, cN1, and multiple NETs were identified as independent predictors of LN metastasis. LN metastasis of rectal NETs was associated with significantly poor disease-free and disease-specific survival. CONCLUSIONS: As risk factors increase, the potential for rectal NETs to metastasize to the LNs increases and LN metastasis is associated with a poor prognosis. This is the first study to report multiple NETs as a risk factor for LN metastasis. A future study examining the survival benefit of radical surgery accompanying LN dissection compared with local resection is warranted.

Adding Induction Chemotherapy Before Chemoradiotherapy with Total Mesorectal Excision and Selective Lateral Lymph Node Dissection for Patients with Poor-Risk, Locally Advanced, Mid-to-Low Rectal Cancer May Improve Oncologic Outcomes: A Propensity Score-Matched Analysis.

BACKGROUND: This study aimed to investigate whether the addition of induction chemotherapy before chemoradiotherapy (CRT) and total mesorectal excision (TME) with selective lateral lymph node dissection improves disease-free survival for patients with poor-risk, mid-to-low rectal cancer. METHODS: The authors' institutional prospective database was queried for consecutive patients with clinical stage II or III, primary, poor-risk, mid-to-low rectal cancer who received neoadjuvant treatment followed by TME from 2004 to 2019. The outcomes for the patients who received induction chemotherapy before neoadjuvant CRT (induction-CRT group) were compared (via log-rank tests) with those for a propensity score-matched cohort of patients who received neoadjuvant CRT without induction chemotherapy (CRT group). RESULTS: From 715 eligible patients, the study selected two matched cohorts with 130 patients each. The median follow-up duration was 5.4 years for the CRT group and 4.1 years for the induction-CRT group. The induction-CRT group had significantly higher rates of 3-year disease-free survival (83.5 % vs 71.4 %; p = 0.015), distant metastasis-free survival (84.3 % vs 75.2 %; p = 0.049), and local recurrence-free survival (98.4 % vs 94.4 %; p = 0.048) than the CRT group. The pathologically complete response rate also was higher in the induction-CRT group than in the CRT group (26.2 % vs 10.0 %; p < 0.001). Postoperative major complications (Clavien-Dindo classification ≥III) did not differ significantly between the two groups (12.3 % vs 10.8 %; p = 0.698). CONCLUSIONS: The addition of induction chemotherapy to neoadjuvant CRT appeared to improve oncologic outcomes significantly, including disease-free survival, for the patients with poor-risk, mid-to-low rectal cancer who underwent TME using selective lateral lymph node dissection.

Nomogram as a novel predictive tool for lymph node metastasis in T1 colorectal cancer treated with endoscopic resection: a nationwide, multicenter study.

BACKGROUND AND AIMS: Since 2009, the Japanese Society for Cancer of the Colon and Rectum guidelines have recommended that tumor budding and submucosal invasion depth, in addition to lymphovascular invasion and tumor grade, be included as risk factors for lymph node metastasis (LNM) in patients with T1 colorectal cancer (CRC). In this study, a novel nomogram was developed and validated by usirge-scale, real-world data, including the Japanese Society for Cancer of the Colon and Rectum risk factors, to accurately evaluate the risk of LNM in T1 CRC. METHODS: Data from 4673 patients with T1 CRC treated at 27 high-volume institutions between 2009 and 2016 were analyzed for LNM risk. To prepare a nonrandom split sample, the total cohort was divided into development and validation cohorts. Pathologic findings were extracted from the medical records of each participating institution. The discrimination ability was measured by using the concordance index, and the variability in each prediction was evaluated by using calibration curves. RESULTS: Six independent risk factors for LNM, including submucosal invasion depth and tumor budding, were identified in the development cohort and entered into a nomogram. The concordance index was .784 for the clinical calculator in the development cohort and .790 in the validation cohort. The calibration curve approached the 45-degree diagonal in the validation cohort. CONCLUSIONS: This is the first nomogram to include submucosal invasion depth and tumor budding for use in routine pathologic diagnosis based on data from a nationwide multi-institutional study. This nomogram, developed with real-world data, should improve decision-making for an appropriate treatment strategy for T1 CRC.

Geriatric nutritional risk index after neoadjuvant chemoradiotherapy and survival in older patients with advanced rectal cancer.

PURPOSE: To investigate the clinical impact of malnutrition on the survival of older patients with advanced rectal cancer who underwent neoadjuvant chemoradiotherapy. METHODS: We investigated the clinical significance of the geriatric nutritional risk index (GNRI) in 237 patients aged over 60 years with clinical stage II/III rectal adenocarcinoma who were treated with neoadjuvant long-course chemoradiotherapy or total neoadjuvant therapy followed by radical resection from 2004 to 2017. Pre-treatment and post-treatment GNRI were evaluated, with patients split into low (< 98) and high (≥ 98) GNRI groups. The prognostic impact of pre-treatment and post-treatment GNRI levels on overall survival (OS), post-recurrence survival (PRS), and disease-free survival (DFS) was evaluated using univariate and multivariate analyses. RESULTS: Fifty-seven patients (24.1%) before neoadjuvant treatment and 94 patients (39.7%) after neoadjuvant treatment were categorized with low GNRI. Pre-treatment GNRI levels were not associated with OS (p = 0.80) or DFS (p = 0.70). Patients in the post-treatment low GNRI group had significantly poorer OS than those in the post-treatment high GNRI group (p = 0.0005). The multivariate analysis showed that post-treatment low GNRI levels were independently associated with poorer OS (hazard ratio, 3.06; 95% confidence interval, 1.55-6.05; p = 0.001). Although post-treatment GNRI levels were not associated with DFS (p = 0.24), among the 50 patients with recurrence, post-treatment low GNRI levels were associated with poorer PRS (p = 0.02). CONCLUSION: Post-treatment GNRI is a promising nutritional score associated with OS and PRS in patients over 60 years with advanced rectal cancer treated with neoadjuvant chemoradiotherapy.

Inferior versus medial approach in laparoscopic colectomy with complete mesocolic excision and D3 lymphadenectomy for right-sided colon cancer: A propensity-score-matched analysis.

AIM: In laparoscopic colectomy with complete mesocolic excision and D3 lymphadenectomy for right-sided colon cancer, either an inferior approach (IA) or a medial approach (MA) is selected in our institution based on the surgeon's preference. The present study compared the treatment outcomes between IA and MA. METHOD: This retrospective, single-centre study using propensity score matching analysed the short- and long-term outcomes of laparoscopic surgery in patients with right-sided colon cancer from 2010 to 2019 at Cancer Institute Hospital. RESULTS: After patient selection, 1011 patients remained for the analysis, of which 67% underwent IA surgery and 33% underwent MA surgery. After propensity score matching (1:1), 325 patients in each group were analysed. Regarding the short-term outcomes, there were no significant differences in the operation time, rate of conversion to open surgery or postoperative complication rate (Clavien-Dindo Grade ≥ III) between the two groups, although the intra-operative median blood loss was significantly less in the IA group than in the MA group (IA, 13 ml vs. MA, 20 ml, P < 0.0001). Regarding the long-term outcomes, the relapse-free survival, liver-relapse-free survival, cancer-specific survival and overall survival were all similar between groups. CONCLUSION: Both the IA and MA in laparoscopic colectomy with complete mesocolic excision and D3 lymphadenectomy for right-sided colon cancer are safe and feasible approaches; the IA may have an advantage over the MA in terms of reduced intra-operative blood loss. Based on their similar oncological outcomes, either the IA or MA can be selected, based on one's preference.

International standardization and optimization group for intersphincteric resection (ISOG-ISR): modified Delphi consensus on anatomy, definition, indication, surgical technique, specimen description and functional outcome.

AIM: Intersphincteric resection (ISR) is an oncologically complex operation for very low-lying rectal cancers. Yet, definition, anatomical description, operative indications and operative approaches to ISR are not standardized. The aim of this study was to standardize the definition of ISR by reaching international consensus from the experts in the field. This standardization will allow meaningful comparison in the literature in the future. METHOD: A modified Delphi approach with three rounds of questionnaire was adopted. A total of 29 international experts from 11 countries were recruited for this study. Six domains with a total of 37 statements were examined, including anatomical definition; definition of intersphincteric dissection, intersphincteric resection (ISR) and ultra-low anterior resection (uLAR); indication for ISR; surgical technique of ISR; specimen description of ISR; and functional outcome assessment protocol. RESULTS: Three rounds of questionnaire were performed (response rate 100%, 89.6%, 89.6%). Agreement (≥80%) reached standardization on 36 statements. CONCLUSION: This study provides an international expert consensus-based definition and standardization of ISR. This is the first study standardizing terminology and definition of deep pelvis/anal canal anatomy from a surgical point of view. Intersphincteric dissection, ISR and uLAR were specifically defined for precise surgical description. Indication for ISR was determined by the rectal tumour's maximal radial infiltration (T stage) below the levator ani. A new surgical definition of T3isp was reached by consensus to define T3 low rectal tumours infiltrating the intersphincteric plane. A practical flowchart for surgical indication for uLAR/ISR/abdominoperineal resection was developed. A standardized ISR surgical technique and functional outcome assessment protocol was defined.

The evaluation of postoperative bowel dysfunction in Japanese patients with rectal cancer.

PURPOSE: The present study assessed postoperative bowel dysfunction in Japanese patients with rectal cancer, including patients who underwent preoperative radiotherapy (RT). METHODS: A total of 277 rectal cancer patients who underwent primary resection were included in the analyses. A questionnaire survey was administered using the low anterior resection syndrome (LARS) score and Wexner score. Scores were determined one year after rectal surgery or diverting ileostomy closure. The LARS score was categorized as minor LARS (21-29) and major LARS (30-42). RESULTS: The proportions of patients with minor and major LARS were significantly larger and Wexner scores significantly higher in patients with distal tumors and a lower anastomosis level than in those with proximal tumors and a higher anastomosis level. Among the patients with lower rectal cancer, the proportions with minor and major LARS were similar between those with and without preoperative RT. The Wexner scores in patients with preoperative RT were significantly higher than in patients without RT. A distal tumor location and lower anastomosis level were independent risk factors of major LARS in multivariate analyses. CONCLUSION: A distal tumor location, low anastomosis level, and preoperative RT might be associated with postoperative bowel dysfunction in rectal cancer patients.

Novel mobilization of the medial approach without changing the position for robotic right hemicolectomy.

Conventional laparoscopic or robotic surgery for right-sided colon cancer often requires intraoperative repositioning and removal of the bowel. Changing positions during robotic surgery can be troublesome and robotic removal of the small intestine carries a risk of unexpected injury because robotic devices have a strong grasping force and no sense of touch. Herein, we introduce a novel mobilization of the medial approach without changing the position for robotic right hemicolectomy. Using this technique, mobilization is performed in counterclockwise succession, allowing all mobilizations and bowel removal to be completed sequentially, without positional change.

Advantages of the umbilical minilaparotomy-first approach in robotic rectal cancer surgery.

BACKGROUND: Since 2018, we have performed robotic rectal cancer surgery at our institution via the umbilical mini-laparotomy-first approach. In the present technical note, we introduce the advantages of this approach. METHODS: In this approach, a 3-cm mini-laparotomy and the wound protector attachment are performed prior to port placement for the da Vinci® Xi system. During robotic surgery, the assistant can adjust the location of the camera port within the wound protector. RESULTS: This approach is only different from the standard port placement in terms of the timing of minilaparotomy; therefore, there is no additional cost. This approach has several advantages. 1: Intraabdominal adhesion around the umbilicus can be dissected under direct vision. 2: Robot arm collision can be diminished. 3: The diverting stoma can be located just at the preoperative stoma-site marking. 4: The da Vinci® camera is less likely to be dirty. 5: Assistant ports can be added through the wound protector. However, sometimes interference between the wound protector extends inside the abdomen and other ports can be a problem, especially in small patients. A smaller-size wound protector is thus recommended in such cases. CONCLUSIONS: The umbilical minilaparotomy-first approach in robotic rectal cancer surgery is a simple and feasible technique with great advantages for not only ensuring successful robotic surgery but also reducing the stoma-associated complications.

Estrogen Receptor-ß Gene Cytosine-Adenine (ESR2-CA) Repeat Polymorphism in Postmenopausal Colon Cancer.

The pathobiological role of estrogen is controversial in colorectal cancer. Cytosine-adenine (CA) repeat in the estrogen receptor (ER)-ß gene (ESR2-CA) is a microsatellite, as well as representative of ESR2 polymorphism. Though its function is unknown, we previously showed that a shorter allele (germline) increased the risk of colon cancer in older women, whereas it decreased it in younger postmenopausal women. ESR2-CA and ER-ß expressions were examined in cancerous (Ca) and non-cancerous (NonCa) tissue pairs from 114 postmenopausal women, and comparisons were made considering tissue types, age/locus, and the mismatch repair protein (MMR) status. ESR2-CA repeats <22/≥22 were designated as 'S'/'L', respectively, resulting in genotypes SS/nSS (=SL&LL). In NonCa, the rate of the SS genotype and ER-ß expression level were significantly higher in right-sided cases of women ≥70 (≥70Rt) than in those in the others. A decreased ER-ß expression in Ca compared with NonCa was observed in proficient-MMR, but not in deficient-MMR. In NonCa, but not in Ca, ER-ß expression was significantly higher in SS than in nSS. ≥70Rt cases were characterized by NonCa with a high rate of SS genotype or high ER-ß expression. The germline ESR2-CA genotype and resulting ER-ß expression were considered to affect the clinical characteristics (age/locus/MMR status) of colon cancer, supporting our previous findings.

Lymph Node Mapping in Transverse Colon Cancer Treated Using Laparoscopic Colectomy With D3 Lymph Node Dissection.

BACKGROUND: Laparoscopic surgery for transverse colon cancer has been excluded from 7 randomized trials for various reasons. The optimal procedure for transverse colon cancer remains controversial. OBJECTIVE: This study aimed to analyze the patterns of lymph node metastasis in transverse colon cancer and to report short- and long-term outcomes of the treatment procedures. DESIGN: This was a single-center retrospective study. SETTINGS: This study was conducted at Cancer Institute Hospital, Tokyo, Japan. PATIENTS: We enrolled 252 patients who underwent laparoscopic surgery for transverse colon cancer. INTERVENTIONS: The transverse colon was divided into 3 segments, and the procedures for transverse colon cancer were based on these segments, as follows: right hemicolectomy, transverse colectomy, and left hemicolectomy. MAIN OUTCOME MEASURES: Postoperatively, the surgeons identified and mapped the lymph nodes from specimens and performed formalin fixation separately to compare the results of the pathological findings. RESULTS: For right-sided, middle-segment, and left-sided transverse colon cancers, the frequency of lymph node metastases was 28.2%, 19.2%, and 19.2%. Skipped lymph node metastasis occurred in right-sided and left-sided transverse colon cancers but not in middle-segment transverse colon cancers. The pathological vascular invasion rate was significantly higher in right and left hemicolectomy than in transverse colectomy. For right hemicolectomy, transverse colectomy, and left hemicolectomy, 5-year overall survival rates were 96.3%, 92.7%, and 93.7%, and relapse-free survival rates were 92.4%, 88.3%, and 95.5%. In multivariate analysis, the independent risk factor for relapse-free survival was lymph node metastasis. LIMITATIONS: Selection bias and different backgrounds may have influenced surgical and long-term outcomes. CONCLUSION: Laparoscopic surgery for transverse colon cancer may be a feasible technique. Harvested lymph node mapping after laparoscopic resection based on D3 lymphadenectomy may help guide the field of dissection when managing patients who have transverse colon cancer. The only independent prognostic factor for relapse-free survival was node-positive cancer. See Video Abstract at http://links.lww.com/DCR/B706.MAPEO DE GANGLIOS LINFÁTICOS EN CÁNCER DE COLON TRANSVERSO TRATADO MEDIANTE COLECTOMÍA LAPAROSCÓPICA CON LINFADENECTOMÍA D3ANTECEDENTES:La cirugía laparoscópica en casos de cáncer de colon transverso fué excluida de siete estudios randomizados mayores por diversas razones. El procedimiento más idóneo en casos de cáncer de colon transverso, sigue siendo controvertido.OBJETIVO:Analizar los patrones de las metástasis en los ganglios linfáticos en casos de cáncer de colon transverso y reportar los resultados a corto y largo plazo de los diferentes procedimientos para su tratamiento.DISEÑO:Estudio retrospectivo en un solo centro de referencia.AJUSTE:Estudio llevado a cabo en el Hospital del Instituto del Cancer, Tokio, Japón.PACIENTES:Fueron incluidos 252 pacientes, sometidos a cirugía laparoscópica por cáncer de colon transverso.INTERVENCIONES:El colon transverso fué dividido en tres segmentos y los procedimientos en casos de cáncer se basaron sobre estos segmentos del tranverso, de la siguiente manera: hemicolectomía derecha, colectomía transversa y hemicolectomía izquierda.PRINCIPALES MEDIDAS DE RESULTADO:En el postoperatorio, los cirujanos identificaron y mapearon los ganglios linfáticos de las piezas quirúrgicas y las fijaron con formaldehido por separado para así poder comparar los resultados con los hallazgos histopatológicos.RESULTADOS:En los cánceres de colon transverso del segmento derecho, del segmento medio y del segmento izquierdo, la frecuencia de metástasis en los ganglios linfáticos fue del 28,2%, 19,2% y 19,2%, respectivamente. Las metástasis en los ganglios linfáticos omitidos se produjo en los cánceres de colon transverso del lado derecho y del lado izquierdo, pero no en los cánceres de colon transverso del segmento medio. La tasa de invasión vascular patológica fue significativamente mayor en la hemicolectomía derecha e izquierda que en la colectomía transversa. Para la hemicolectomía derecha, colectomía transversa y hemicolectomía izquierda, las tasas de supervivencia general a cinco años fueron del 96,3%, 92,7% y 93,7%, y las tasas de supervivencia sin recaída fueron del 92,4%, 88,3% y 95,5%, respectivamente. En el análisis multivariado, el factor de riesgo independiente para la sobrevida sin recidiva fue la metástasis en los ganglios linfáticos.LIMITACIONES:El sesgo de selección y los diferentes antecedentes pueden haber influido en los resultados quirúrgicos a largo plazo.CONCLUSIONES:La cirugía laparoscópica en casos de cáncer de colon transverso puede ser una técnica factible. El mapeo de los ganglios linfáticos recolectados después de la resección laparoscópica basada en la linfadenectomía D3 puede ayudar a guiar el campo de la disección en el manejo de pacientes con cáncer de colon transverso. El único factor pronóstico independiente para el SLR fue el cáncer con ganglios positivos. Consulte Video Resumen en http://links.lww.com/DCR/B706. (Traducción-Dr. Xavier Delgadillo).