Low Rectal Adenocarcinoma Research Articles

Which is safer in anastomosis, transanal or robotic total mesorectal excision?

The article “ A multicenter matched comparison of transanal and robotic total mesorectal excision for mid and low-rectal adenocarcinoma ” as published in the 2018 issue of Annals of Surgery , reports very informative data. The transanal total mesorectal excision (TaTME) is the most noteworthy item in recent years. Surgical robot enables precise dissection within narrow and deep pelvis. Therefore, it is a very useful tool to perform total mesorectal excision (robotic TME, RTME).

Rectal cancer surgery: can a clinical trial be conducted today?

The article entitled “A Multicenter Matched Comparison of Transanal and Robotic Total Mesorectal Excision for Mid and Low-rectal Adenocarcinoma”, published by Lee et al . (1), could, in our view, be the reference as to answer the question “what is the best surgery for low-rectal carcinoma?”

Application value of texture analysis of magnetic resonance images in prediction of neoadjuvant chemoradiotherapy efficacy for rectal cancer

To explore the application value of texture analysis of magnetic resonance images (MRI) in predicting the efficacy of neoadjuvant chemoradiotherapy(nCRT) for rectal cancer. A total of 34 rectal cancer patients who were hospitalized at Zhejiang Provincial People's Hospital from February 2015 to April 2017 were prospectively enrolled and received 3.0T MRI examination at pre-nCRT (1 day before nCRT), early stage (at 10-day after nCRT) and middle stage (at 20-day after nCRT). distance from tumor lower margin to anal edge was less than 12 cm under rectoscope; rectal cancer was confirmed by preoperative pathology; clinical stage was T3 or above; lymph node metastasis existed but without distant metastasis; functions of liver, kidney and heart present no contraindications of operation. unfinished nCRT, surgery and three examinations of MRI; image motion artifacts; lack of postoperative pathological results. All the patients underwent rectal cancer long-term three-dimensional radiotherapy and chemotherapy combined with nCRT (oxaliplatin plus capecitabine). The tumor regression grading (TRG) was divided into TRG 0 to 4 grade after nCRT, and TRG 4 was classified as pathological complete remission (pCR); TRG 2 to 3 was classified as partial remission (PR); the rest was no remission (NR). Extraction and analysis of texture features in T2-weighted MR-defined tumor region were performed using Omni Kinetics texture software. The texture values of each time point were statistically analyzed, and the differences of texture values and change differences between pCR and PR+NR, and NR and pCR+PR were compared respectively. Statistically significant texture values were screened and were used in receiver operating characteristic (ROC) curve to assess the prediction of the efficacy of nCRT. Of 34 patients, 21 were males and 13 were females with median age of 49.3 years. Nineteen (55.9%) patients were low rectal adenocarcinoma and 15 (44.1%) patients were middle rectal adenocarcinoma. Nine (26.5%) cases belonged to pCR, 13 (38.2%) belonged to PR, and 12 (35.3%) belonged to NR. Before nCRT, the entropy of tumor area in pCR patients was significantly higher than that in PR+NR patients (7.164±0.272 vs. 6.823±0.309, t=2.925, P=0.006). At the middle stage of nCRT, as compared with PR+NR patients for the texture features of tumor region, the variance (1566±281 vs. 2883±867, t=-4.435, P=0.000) and entropy(5.436±0.934 vs. 6.803±0.577, t=-4.118,P=0.002) of pCR patients were significantly lower; kurtosis(4.800±1.288 vs. 3.206±1.211, t=3.333, P=0.002) and energy (0.016±0.005 vs. 0.010±0.004, t=3.240, P=0.003) of pCR patients were significantly higher. As compared to pCR+PR patients, the kurtosis(2.461±0.931 vs. 4.264±1.205, t=-4.493, P=0.000) and energy (0.011±0.004 vs. 0.014±0.004, t=-3.453, P=0.000) of the NR patients were significantly lower. As for texture change values between early stage and middle stage, the entropy difference was significant between pCR and PR+NR, NR and pCR+PR (1.344±0.819 vs. 0.489±0.319, t=3.047, P=0.014; 0.446±0.213 vs. 0.917±0.677, t=-3.638, P=0.001, respectively). As for texture change values between pre-nCRT and middle stage, variance and entropy differences between pCR and PR+NR (1759±1226 vs. 977±842, t=2.113, P=0.042; 1.728±0.918 vs. 0.524±0.355, t=3.832, P=0.004), and the change values of entropy between NR and pCR+PR (0.475±0.349 vs. 1.044±0.860, t=-2.722, P=0.011) were statistically significant. The above indicators were included in the ROC curve. The results revealed that at the middle stage, entropy value >5.983 indicated the best efficacy for the diagnosis of pCR, with the area under the ROC curve (AUC) of 0.885, the sensitivity of 100%, and the specificity of 66.7%; the energy <0.010 indicated the best AUC for diagnosis of NR was 0.902, with the sensitivity of 91.7% and specificity of 81.8%. Texture analysis based on T2 weighted images can predict the efficacy of nCRT for rectal cancer. The middle stage of nCRT is the best time of prediction. The entropy and energy of this period are texture parameters having higher predictive ability.

Phase I/II Study of Preoperative Chemoradiotherapy With TEGAFIRI for Locally Advanced Rectal Cancer

IntroductionChemoradiotherapy (CRT) is the standard treatment for locally advanced rectal cancer; however, the optimal chemotherapy sequence to administer simultaneously with radiotherapy remains unclear. We conducted a phase I/II study to test a new regimen, TEGAFIRI (combination tegafur, uracil [UFT], leucovorin [LV], irinotecan), for patients with locally advanced rectal cancer. Patients and MethodsA total of 22 patients with locally advanced lower rectal adenocarcinoma were enrolled in the present study. The radiation dose was 50.4 Gy in 28 fractions. UFT (300 mg/m2/d) and LV (75 mg/body weight/d) were administered orally 3 times daily. Irinotecan was administered as an intravenous infusion at 3 escalating dose levels. The initial dose was 50 mg/m2 (level 1; n = 7), the intermediate was 70 mg/m2 (level 2; n = 8), and the maximum was 80 mg/m2 (level 3; n = 7). The drug was administered on days 1, 15, 29, and 43. ResultsDose-limiting toxicity was not observed at any dosing level. The most frequent adverse event was leukopenia (50%), followed by diarrhea (45.5%), anal pain (31.8%), and neutropenia (27.3%). All were well-managed with the appropriate drugs. The total pathologic complete response rate was 22.7%, and the proportion of good responders was 28.6%, 50%, and 71.4% at levels 1, 2, and 3, respectively. None of the patients experienced local recurrence. The 5-year relapse-free and overall survival rates were 80.4% and 80.8%, respectively. ConclusionTEGAFIRI is a promising CRT regimen that results in marked tumor regression and good local control. Moreover, its adverse events are well-tolerated.

Laparoscopic Pelvic Exenteration for Locally Advanced Rectal Cancer, Technique and Short-Term Outcomes.

Background: Since last two decades minimally invasive techniques have revolutionized surgical field. In 2003 Pomel first described laparoscopic pelvic exenteration, since then very few reports have described minimally invasive approaches for total pelvic exenteration. Methods: We report the 10 cases of locally advanced rectal adenocarcinoma which were operated between the periods from March 1, 2017 to November 11, 2017 at the Tata Memorial Hospital, Mumbai. All male patients had lower rectal cancer with prostate involvement on magnetic resonance imaging (MRI). One female patient had uterine and fornix involvement. All perioperative and intraoperative parameters were collected retrospectively from prospectively maintained electronic data. Results: Nine male patients with diagnosis of nonmetastatic locally advanced lower rectal adenocarcinoma were selected. All patients were operated with minimally invasive approach. All patients underwent abdominoperineal resection with permanent sigmoid stoma. Ileal conduit was constructed with Bricker's procedure through small infraumbilical incision (4-5 cm). Lateral pelvic lymph node dissection was done only when postchemoradiotherapy MRI showed enlarged pelvic nodes. All 10 patients received neoadjuvant chemo radiotherapy, whereas 8 patients received additional neoadjuvant chemotherapy. Mean body mass index was 21.73 (range 19.5-26.3). Mean blood loss was 1000 mL (range 300-2000 mL). Mean duration of surgery was 9.13 hours (range 7-13 hours). One patient developed paralytic ileus, which was managed conservatively. One patient developed intestinal obstruction due to herniation of small intestine behind the left ureter and ileal conduit. The same patient developed acute pylonephritis, which was managed with antibiotics. Mean postoperative stay was 14.6 days (range 9-25 days). On postoperative histopathology, all margins were free of tumor in all cases. Conclusion: Minimally invasive approaches can be used safely for total pelvic exenteration in locally advanced lower rectal adenocarcinoma. All patients had fast recovery with less blood loss. In all patients R0 resection was achieved with adequate margins. Long-term oncological outcomes are still uncertain and will require further follow-up.

Comparative analysis of robot-assisted vs. open abdominoperineal resection in terms of operative and initial oncological outcomes

PurposeThe present study aimed to objectively evaluate robot-assisted abdominoperineal resection (APR) in comparison with open APR, in terms of operative elements and initial oncological outcomes.MethodsA total of 118 patients with lower rectal adenocarcinoma who had undergone curative APR were consecutively enrolled between June 2010 and June 2016, i.e., robot-assisted group (n = 40) and open group (n = 78).ResultsTransabdominal extralevator muscle excision was more frequently performed in the robot-assisted group than in the open group (68% vs. 42%, P = 0.012). In the robot-assisted group, the pain score at one day after surgery was less than in the open group, and the resumption of bowel function was earlier (P = 0.043 and P = 0.002, respectively). The occurrence of circumferential resection margin involvement (CRM+) was more than 5 times greater in the open group than in the robot-assisted group, presenting a marginal significance (P = 0.057). Although important postoperative morbidity did not generally differ between the 2 groups, voiding difficulty and male sexual dysfunction appeared to be encountered more frequently in the open group than in the robot-assisted group.ConclusionThe robot-assisted APR facilitated transabdominal extralevator excision and bowel recovery and demonstrated a trend towards reduced CRM+.

Preoperative T staging using CT colonography with multiplanar reconstruction for very low rectal cancer

BackgroundPreoperative T staging of lower rectal cancer is an important criterion for selecting intersphincteric resection (ISR) or abdominoperineal resection (APR) as well as selecting neoadjuvant therapy. The aim of this study was to evaluate the accuracy of preoperative T staging using CT colonography (CTC) with multiplanar reconstruction (MPR), in which with the newest workstation the images can be analyzed with a slice thickness of 0.5 mm.MethodsBetween 2011 and 2013, 45 consecutive patients with very low rectal adenocarcinoma underwent CTC with MPR. The accuracy of preoperative T staging using CTC with MPR was evaluated. The accuracy of preoperative T staging using MRI in the same patient population (34 of 45 patients) was also examined.ResultsOverall accuracy of T staging was 89% (41/45) for CTC with MPR and 71% (24/34) for MRI. CTC with MPR was particularly sensitive for pT2 tumors (82%; 14/17), whereas MRI tended to overstage pT2 tumors and its sensitivity for pT2 was 53% (8/15).ConclusionsCTC with MPR, with an arbitrary selection, could be aligned to the tumor axis and better demonstrated tumor margins consecutively including the deepest section of the tumor. The accuracy of T2 and T3 staging using CTC with MPR seemed to surpass that of MRI, suggesting a potential role of CTC with MPR in preoperative T staging for very low rectal cancer.

Oncologic Outcomes for Low Rectal Adenocarcinoma after Low-Anterior Resection with Coloanal Anastomosis vs Abdominoperineal Resection: A National Cancer Database Propensity Matched Analysis

Oncologic Outcomes for Low Rectal Adenocarcinoma after Low-Anterior Resection with Coloanal Anastomosis vs Abdominoperineal Resection: A National Cancer Database Propensity Matched Analysis

Laparoscopic Versus Open Lateral Lymph Node Dissection for Locally Advanced Low Rectal Cancer: A Subgroup Analysis of a Large Multicenter Cohort Study in Japan.

Mesorectal excision with lateral lymph node dissection is the standard treatment for locally advanced low rectal cancer in Japan. However, the safety and feasibility of laparoscopic lateral lymph node dissection remain to be determined. The purpose of this study was to evaluate the safety and feasibility of laparoscopic versus open lateral lymph node dissection for locally advanced low rectal cancer. This was a retrospective cohort study using an exact matching method. We conducted a multicenter study of 69 specialized centers in Japan. Patients with consecutive midrectal or low rectal adenocarcinoma cancer stage II to III who underwent mesorectal excision with curative intent between 2010 and 2011 were recruited. Short-term and oncological outcomes were compared between the laparoscopic and open-surgery groups. Of the 1500 eligible patients, 676 patients who underwent lateral lymph node dissection were analyzed, including 137 patients who were treated laparoscopically and 539 patients who were treated with open surgery. After matching, the patients were stratified into laparoscopic (n = 118) and open-surgery (n = 118) groups. Operative times in the overall cohort were significantly longer (461 vs 372 min) in the laparoscopic versus the open-surgery group. In the laparoscopic group, the blood loss volume was significantly smaller (193 vs 722 mL), with fewer instances of blood transfusion (7.3% vs 25.5%) compared with the open-surgery group. The postoperative complication rates were 35.8% and 43.6% for the laparoscopic and open-surgery groups (p = 0.10). The 3-year relapse-free survival rates were 80.3% and 72.6% for the laparoscopic and open-surgery groups (p = 0.07). The study was limited by its retrospective design and potential selection bias. Laparoscopic lateral lymph node dissection is safe and feasible for cancer stage II to III low rectal cancer and is associated with similar oncological outcomes as open lateral lymph node dissection. See Video Abstract at http://links.lww.com/DCR/A334.

Preoperative chemoradiotherapy changes the size criterion for predicting lateral lymph node metastasis in lower rectal cancer.

The purpose of this study was to identify the size criteria of lateral lymph node metastasis in lower rectal cancer both in patients who underwent preoperative CRT and those who did not. This study enrolled 150 patients who underwent resection for primary lower rectal adenocarcinoma with lateral lymph node dissection between 2013 and 2015. Patients were divided into two groups: the CRT group, treated with preoperative chemoradiotherapy before surgery, and the non-CRT group, treated with surgery alone. The short-axis diameter of each dissected lateral lymph node was measured. Receiver-operating characteristic curves were generated to reveal the optimal cutoff values for determining lateral lymph node metastasis in both groups. In the non-CRT group (n=131), the ROC curve demonstrated that the optimal cutoff value for determining metastasis was 6.0mm, with a sensitivity of 78.5% and specificity of 82.9%, and the AUC was 0.845. In comparison, in the CRT group (n=19), the optimal cutoff value was 5.0mm, with a sensitivity of 71.4% and specificity of 85.3% and an AUC of 0.836. The cutoff size for determining lateral lymph node metastasis was smaller in the CRT group than in the non-CRT group.

Abstract 3947: Intratumor heterogeneity impacts treatment response in rectal carcinoma

Abstract Individual response to radiochemotherapy (RCT) in rectal cancer patients is highly variable and the underlying mechanisms of treatment resistance of cancer cells are poorly understood. Recent studies revealed a considerable degree of genomic tumor heterogeneity. We hypothesize that this heterogeneity has a direct impact on treatment response as subpopulations of cancer cells are resistant to currently used RCT and facilitate tumor growth under treatment. To address this highly relevant clinical issue, patient-derived rectal cell lines were established. The tissue was derived from a 59-year-old male presenting with an adenocarcinoma of lower rectum (T3,N1,M0), who was treated by neoadjuvant RCT (50.4 Gy plus 5-FU) and low anterior resection. The neoadjuvant treatment induced a shrinkage of the tumor (staging of the surgical specimen: ypT3,N0), suggesting a partial response to RCT. A biopsy of the treatment naïve tumor was implanted heterotopically into an immunodeficient nude mouse. After in vivo growth, the tumor was dissociated and introduced to an in vitro culture where murine stromal cells were depleted using antibody-based columns. The cell line proved to be of human origin by immunofluorescence for human Keratin 20 as well as genotyping using short tandem repeat profiling. The characterization of the genome by array CGH and spectral karyotyping (SKY) revealed a highly complex near-triploid karyotype with numerous chromosomal imbalances, which are specific for colorectal cancers, including gains in chromosomes 7, 13 and 20. We also observed other structural abnormalities including an isochromosome 1q. Multiplex-FISH by consecutive hybridization of probes for 15 gene loci, which are known to be relevant in colorectal cancer genesis, revealed a significant degree of clonal heterogeneity of the cell line. Single cell sorting was then performed to establish single cell derived cell lines from the genomically well characterized parental cell line. Exposure of the single cell derived cell lines to irradiation in combination with 3 uM 5-FU revealed substantial differences in treatment response. Analyses of the genome by array CGH and transcriptome by RNA-Seq of the respective single cell derived cell lines are currently underway. This will allow the comparison of the respective sensitivities to RCT to the identified aberration profiles. These data will facilitate the understanding of therapy resistance and potentially allow a reliable prediction of the patient’s response. A tailored therapy is an important step towards individualized treatment in colorectal cancer patients to avoid therapy resistance. Citation Format: Rüdiger Meyer, Nicole E. McNeil, Darawalee Wangsa, Lena Anthuber, Noam Auslander, Danny Wangsa, Zhongqiu Zhang, Daniel Rosenberg, Eytan Ruppin, Jens K. Habermann, Thomas Ried. Intratumor heterogeneity impacts treatment response in rectal carcinoma [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2017; 2017 Apr 1-5; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2017;77(13 Suppl):Abstract nr 3947. doi:10.1158/1538-7445.AM2017-3947

Sphincter-preserving surgery for low-middle rectal cancer

The study proposed to evaluate the feasibility of predicting sphincter-sparing surgery (SSS) preoperatively in low-middle rectal cancer by using magnetic resonance (MR).The study included both retrospective and prospective design. In the retrospective design, the distance from lower edge of tumor to upper margin of the internal sphincter (Dis1) and distance to anal verge (Dis2) were measured on MR, the distance to anal verge recorded by colonoscopy (Dis3) and digital rectal examination (Dis4) were also obtained. ROC analysis was conducted and cut-off value was determined with overall and stratified analysis. The prospective part was designed to validate the predictive capability of the optimal distance.The retrospective design included 278 patients with middle or lower rectal adenocarcinoma, the prospective design included 106 patients with neoadjuvant therapies. The primary outcome was the actual surgical method and pathological distal resection margin. Dis1 obtained from MRI presented better performance than other distances in determining the surgical approach, with AUC of 0.997 (95% CI, 0.934-1.000). Dis1 was selected as the optimal distance and a cut-off value of 2 cm was determined. Dis1 and the cut-off value were also validated in the prospective sample, with AUC of 0.996 (95% CI, 0.989-1.000) and an overall accuracy of 99.1%.MR-based distance from lower edge of tumor to upper margin of the internal sphincter could be used to help the surgeons to predict the feasibility of SSS preoperatively.

Laparoscopic Abdominoperineal Resection for Low Rectal Cancer at National Cancer Hospital of Vietnam

Introduction: Results of laparoscopic colectomies from developing nations are reported rarely. We report our results of laparoscopic abdominoperineal resec-tion (LAPR) for low rectal cancer at K Hospital (National Cancer Hospital of Vietnam). Materials & Methods: From January 2012 to December 2015, a to-tal of 135 patients who were diagnosed with low rectal adenocarcinoma were recruited to evaluate for LAPR surgical outcome performed at the K Hospital in Vietnam. The goal of the study was to compare post-surgical data from K Hos-pital with Western countries. Data were collected including age, gender, history of previous abdominal surgery, operative time, estimated blood loss (EBL), conversion rate, number of harvested lymph nodes, complications, time to re-turn of bowel function (TRBF), length of stay (LOS), TNM staging and overall survival. Results: There were 69 male and 66 female patients. The mean age at diagnosis was 55.3 years (range 29 - 68 years). 19 patients had previous ab-dominal surgeries. One patient had a conversion to open LAPR due to ureteral and bladder injury. The mean and standard deviation for number of harvested lymph nodes was 14.6 ± 5.3; mean operative time 133 ± 20.9 minutes and mean EBL 13.6 ± 12.2 ml. There were two cases of urinary retention that required bladder catheterization for more than 48 hours. There was no perioperative mortality. The TRBF was 33 ± 4.4 hours. Mean LOS was 7.4 ± 1.8 days. 98 patients (72.6%) had stage II and 37 patients (27.4%) had stage III disease. The overall 1-year, 2-year and 3-year survival was 95.8%, 82.1% and 73.3%, respectively. Conclusion: LAPR for low rectal cancer in K hospital is feasible and safe.

下部直腸・肛門管腺癌に対する鼠径リンパ節郭清の治療成績

目的：教室における下部直腸・肛門管腺癌の鼠径リンパ節郭清（inguinal node dissection；以下，INDと略記）症例の治療成績を明らかにする．対象と方法：1992年から2009年までの，腫瘍下縁がPまたはEの下部直腸・肛門管腺癌手術症例の内，INDを施行した16例（同時性転移7例，異時性転移9例）を対象とし，術後長期成績について検討した．結果：術後合併症はリンパ漏を13例（81.3%），surgical site infection（SSI），下肢の浮腫をそれぞれ3例（18.8%）認めた．平均在院日数は27日だった．術後補助化学療法は6例（37.5%）に施行された．同時性転移7例の5年無再発生存率は28.6%，5年全生存率（overall survival；以下，OSと略記）は28.6%だった．異時性転移9例の初回手術後から鼠径リンパ節転移までの期間は中央値11か月で，IND後4年以内に全例再発を認めたが，5年OSは33.3%だった．IND後の再発例は13例（81.3%）で，初回再発部位は骨盤内が3例，肺，肝臓，対側鼠径リンパ節，大動脈周囲リンパ節，皮膚がそれぞれ2例だった．結語：鼠径リンパ節単独転移を伴う下部直腸・肛門管腺癌に対するINDは，長期生存の可能性もあり施行する意義があるかもしれないが，遠隔再発率は高くIND後の集学的治療の開発が必要であると考えられた．

Short- and Mid-Term Outcomes after Endoscopic Transanal or Laparoscopic Transabdominal Total Mesorectal Excision for Low Rectal Cancer: A Single Institutional Case-Control Study

Transabdominal laparoscopic proctectomy (LAP) for rectal cancer was associated with postoperative recovery improvement. Early studies showed favorable short-term results of endoscopic transanal proctectomy (ETAP), with low conversion rates to open procedures. We aimed to compare efficacy, morbidity, and functional outcomes of ETAP to standard LAP for low rectal cancer. From 2008 to 2013, 72 consecutive patients received proctectomy and coloanal manual anastomosis for low rectal adenocarcinoma. Thirty-four patients had transanal endoscopic proctectomy, and 38 patients underwent the standard laparoscopic procedure. When compared with the LAP group, the ETAP group demonstrated a lower conversion rate to open procedures (23.7% vs 2.9%, respectively; p= 0.015), shorter in-hospital stays (9 vs 8 days, respectively; p= 0.04), and a lower readmission rate (13.2% vs 0%; p= 0.03). Overall postoperative morbidity rates for the LAP and the ETAP groups (36.8% vs 32.4%, respectively; p= 0.69) and functional results (Kirwan score 1/2, 73.7% vs 73.5%, respectively; p=0.85) were comparable; additionally, we found similar oncologic quality criteria (R1 resection 10.5% vs 5.9%, respectively; p= 0.68; grade 3 mesorectal integrity 52.6% vs 55.9%, respectively; p= 0.66). Disease-free survival of 24 months (Kaplan-Meier estimation) was comparable in the 2 groups: 86% in the ETAP group vs 88% in the LAP group; p= 0.91. At the date of last follow-up, 91.2% of ETAP patients and 92.1% of LAP patients were free of stoma. The endoscopic transanal approach could facilitate mesorectal excision and improve short-term outcomes without impairing the oncologic quality of the resection or mid-term functional and oncologic results.

Impact of neoadjuvant therapy in downstaging of lower rectal adenocarcinoma and the role of pelvic magnetic resonance in staging.

to evaluate the effect of neoadjuvant therapy on the stage (TNM) of patients with rectal adenocarcinoma and validate the use of MRI as a method of determining locoregional stage. we conducted a retrospective study of 157 patients with lower rectum adenocarcinoma, whom we divided into two groups: Group 1, 81 patients (52%) who had undergone surgical treatment initially, with the purpose to analyze the accuracy of locoregional staging by pelvic magnetic resonance imaging throug the comparison of radiological findings with pathological ones; Group 2, 76 patients (48%), who had been submitted to neoadjuvant therapy (chemotherapy and radiation) prior to definitive surgical treatment, so as to evaluate its effects on the stage by comparing clinical and radiological findings with pathology. In group 1, the accuracy of determining tumor depth (T) and lymph node involvement (N) was 91.4% and 82.7%, respectively. In group 2, neoadjuvant therapy decreased the T stage, N stage and TNM stage in 51.3%, 21% and 48.4% of cases, respectively. neoadjuvant therapy in patients with rectal adenocarcinoma is effective in decreasing disease stage, and pelvic magnetic resonance imaging is effective for locoregional staging. avaliar o efeito da terapia neoadjuvante, nos pacientes portadores de adenocarcinoma de reto, sobre o estádio (TNM) e validar o emprego da ressonância magnética como método de determinação do estádio locorregional. estudo retrospectivo de 157 pacientes com diagnóstico de adenocarcinoma de reto baixo, que foram divididos em dois grupos: Grupo 1, 81 pacientes (52%), submetidos ao tratamento cirúrgico de princípio, cuja finalidade foi analisar a acurácia da determinação do estádio locorregional pela ressonância magnética da pelve, através da comparação entre os achados radiológicos e os achados anatomopatológicos; Grupo 2, 76 pacientes (48%), encaminhados à terapia neoadjuvante (quimioterapia e radioterapia), antes do tratamento cirúrgico definitivo, com o intuito de avaliar seus efeitos sobre o estádio, através da comparação dos achados clínico-radiológicos com os anatomopatológicos. no grupo 1, a acurácia da determinação da profundidade da lesão (T) e do comprometimento linfonodal (N), foram de 91,4% e 82,7%, respectivamente. No grupo 2, a terapia neoadjuvante diminuiu o estádio T, estádio N e o estádio TNM em 51,3%, 21% e 48,4% dos casos, respectivamente. a terapia neoadjuvante nos pacientes com adenocarcinoma de reto é efetiva na diminuição do estádio e a ressonância magnética da pelve é eficaz na determinação do estádio locorregional.

The circumferential resection margins status: A comparison of robotic, laparoscopic and open total mesorectal excision for mid and low rectal cancer

IntroductionMinimally invasive surgery for rectal cancer (RC) is now widely performed via the laparoscopic approach, but robotic-assisted surgery may overcome some limitations of laparoscopy in RC treatment. We compared the rate of positive circumferential margins between robotic, laparoscopic and open total mesorectal excision (TME) for RC in our institution. MethodsMid and low rectal adenocarcinoma patients consecutively submitted to robotic surgery were compared to laparoscopic and open approach. From our prospective database, 59 patients underwent robotic-assisted rectal surgery from 2012 to 2015 (RTME group) were compared to our historical control group comprising 200 open TME (OTME group) and 41 laparoscopic TME (LTME group) approaches from July 2008 to February 2012. Primary endpoint was to compare the rate of involved circumferential resection margins (CRM) and the mean CRM between the three groups. Secondary endpoint was to compare the mean number of resected lymph nodes between the three groups. ResultsCRM involvement was demonstrated in 20 patients (15.5%) in OTME, 4 (16%) in LTME and 9 (16.4%) in the RTME (p = 0.988). The mean CRM in OTME, LTME and RTME were respectively 0.6 cm (0–2.7), 0.7 cm (0–2.0) and 0.6 cm (0–2.0) (p = 0.960). Overall mean LN harvest was 14 (0–56); 16 (0–52) in OTME, 13 (1–56) in LTME and 10 (0–45) in RTME (p = 0.156). ConclusionOur results suggest that robotic TME has the same oncological short-term results when compared to the open and laparoscopic technique, and it could be safely offered for the treatment of mid and low rectal cancer.

Phase II trial of induction mFOLFOX6 plus bevacizumab followed by neoadjuvant S-1-based chemoradiation for MRI-defined poor-risk rectal cancer.

700 Background: Induction chemotherapy has been explored as a novel treatment option to improve oncological outcomes in poor-risk locally advanced rectal cancer (LARC). Although previous studies have suggested high pCR rate with a favorable toxicity profile in S-1-based neoadjuvant chemoradiation, no study has evaluated induction chemotherapy added with this regimen. The present study is designed to evaluate the safety and efficacy of induction chemotherapy with bevacizumab followed by neoadjuvant S-1 based chemoradiation in MRI-defined poor-risk LARC. Methods: This was a single-center phase II trial at a high-volume cancer center. Eligible patients had low rectal adenocarcinoma with MRI-defined poor-risk features. Patients received 12-week (6 course) mFOLFOX plus bevacizumab (5 mg/kg every 2 weeks) followed by concomitant oral S-1 (80mg/m2/day on days 1-5, 8-12, 22-27, and 29-33) plus radiotherapy (50.4Gy). Surgery was scheduled for 6-10 weeks after chemoradiation. Pathological complete response (pCR) was the primary endpoint. Results: A total of 43 eligible patients were enrolled. Forty-two patients (98%) completed induction chemotherapy. Forty-two patients (98%) completed planned radiation dose. One patient with cCR after completion of preoperative treatment declined surgery, but all the other 42 patients (98%) underwent R0 resection thorough a laparoscopic approach. A pCR was achieved in 16 patients (37%; 95% confidence interval 24.4%-52.1%). CTCAE grade 3 adverse events (AEs) occurred in 4 patients (9.3%) during induction chemotherapy and 5 patients (12%) during chemoradiation. There were no grade 4 AEs. Clavien-Dindo Classification grade III-IV surgical complications occurred in 6 patients (14%), including 1 grade IVa delirium, 1 grade IIIb anastomotic leakage, 1 grade IIIb bleeding, 2 grade IIIa pelvic abscess and 1 grade IIIa urethral fistula. There was no mortality. Conclusions: Induction FOLFOX plus bevacizumab followed by S-1-based chemoradiation achieved a high pCR rate with favorable toxicity and tolerable surgical complications in poor-risk LARC. Phase III trial is needed for further evaluation. Clinical trial information: UMIN000011457.

Quantitative contribution of prognosticators to oncologic outcome after rectal cancer resection.

Prognostication is an important aspect of medical practice. It relies on statistical modeling testing the correlation of variables with the outcome of interest. In contrast with the classic approach of predictive modeling, this study aimed to estimate the unique, individual, and relative contributions. This includes the quantitative contributions of patient-, tumor-, and treatment-related factors to oncologic outcome after rectal cancer resection. This was a retrospective analysis of prospectively registered data. The study included 65 hospitals participating on a voluntary basis in the Project on Cancer of the Rectum, a Belgian multidisciplinary improvement project of rectal cancer care. A total of 1470 patients presenting midrectal or low-rectal adenocarcinoma without distant metastasis were included. The study intervention was total mesorectal excision with or without sphincter preservation. The unique, individual, and relative contributions of a set of covariables to the statistical variability of the distant metastasis rate and overall survival have been calculated. The 5-year distant metastasis rate was 21% and overall survival 76%. A large amount of the variability of the outcomes (ie, 83.6% to 84.2%) could not be predicted by the prognostic factors. Unique contributions of the predictors ranged from 0.1% to 3.1%. The 3 risk factors with the highest unique contribution for distant metastasis were lymph node ratio, pathologic tumor stage, and total mesorectal quality; for overall survival they were age, lymph node ratio, and ASA score. The main weakness of this study was incomplete participation and registration in the Project on Cancer of the Rectum. Several factors influence oncologic outcomes and are present in prediction models. However, the models predict relatively little of outcome variation.

Perineal pseudocontinent colostomy is safe and efficient technique for perineal reconstruction after abdominoperineal resection for rectal adenocarcinoma.

BackgroundThe aim of this study was to evaluate oncologic results and satisfaction rate results of pseudocontinent perineal colostomy (PCPC) using Schmidt’s technique in patients undergoing abdominoperineal resection (APR) for managing low rectal adenocarcinoma.MethodsFrom January 1993 and December 2007, One hundred and forty six patients underwent successfully PCPC after abdominoperineal resection for lower rectal adenocarcinoma. There were 75 women, with an average age of 47 years old. All patients received neoadjuvant radiotherapy with or without chemotherapy. Long-term oncological results and satisfaction rate were evaluated.ResultsAfter a median follow up of 36 months (range 12–156) months, the five-year overall survival and disease free survival rate were 74.6% and 60.3% respectively. Local and distant recurrences occurred respectively in 10 (6,8%) and 29 (20%) patients. Seventy-seven percent (77%) of the patients were highly satisfied with this technique and only one patient was unsatisfied. However, none of them accepted the conversion to an abdominal colostomy neither would have changed PCPC for an iliac colostomy at first intent.ConclusionThis study showed that pseudocontinent perineal colostomy is a safe and reliable pelvic reconstruction technique after abdominoperineal resection for low rectal adenocarcinoma. It provides high degree of patient satisfaction without compromising oncological results. It is a good option in selected patients, especially in Muslim countries.