Preoperative radiation therapy for locally advanced rectal cancer: a comparison between two different time intervals to surgery

Stereotactic MR-guided adaptive radiotherapy (SMART) for primary rectal cancer: evaluation of early toxicity and pathological response

Background

The purpose of this study is to measure the effects of stereotactic MR-guided adaptive radiotherapy (SMART) for rectal cancer patients in terms of early toxicity and pathological response.

Materials and methods

For this prospective pilot study, patients diagnosed with locally advanced rectal cancer (LARC) with positive lymph node clinical staging underwent SMART on rectal lesion and mesorectum using hybrid MR-Linac (MRIdian ViewRay). Dose prescription at 80% isodose for the rectal lesion and mesorectum was 40 Gy (8 Gy/fr) and 25 Gy (5 Gy/fr), respectively, delivered on 5 days (3 fr/week). Response assessment by MRI was performed 3 weeks after SMART, then patients fit for surgery underwent total mesorectal excision. Primary endpoint was evaluation of adverse effect of radiotherapy. Secondary endpoint was pathological complete response rate. Early toxicity was graded according to the Common Terminology Criteria for Adverse Events (CTCAE v5.0).

Results

From October 2020 to January 2022, twenty patients underwent rectal SMART. No grade 3-5 toxicity was recorded. Twelve patients were eligible for total mesorectal excision (TME). Mean interval between the completion of SMART and surgery was 4 weeks. Pathological downstaging occurred in all patients; rate of pathological complete response (pCR) was 17%. pCR occurred with a prolonged time to surgery (> 7 weeks).

Conclusion

To our knowledge, this is the first study to use stereotactic radiotherapy for primary rectal cancer. SMART for rectal cancer is well tolerated and effective in terms of tumor regression, especially if followed by delayed surgery.

Effect of placing double-lumen irrigation-suction tube on closure of anastomotic defect following rectal cancer surgery

PURPOSE

This study aimed to investigate the effect of placement of double-lumen irrigation-suction tubes (DLIST) on the closure of anastomotic defect (AD) after rectal cancer surgery.

METHODS

The study was carried out at two centers managed by one surgeon, both adopted the same treatments. Patients with postoperative AD after rectal cancer surgery from January 2011 to June 2020 were eligible and were divided into a passive drainage (PD) group and a DLIST group according to whether the PD, placed in the rectal cancer surgery, had been replaced with the DLIST. The effect of DLIST on the AL was evaluated.

RESULT

There distributed 76 patients in the DLIST group and 52 in the PD group. A higher closure rate was reported in the DLIST group (46 patients in DLIST group, for a closure rate of 60.5%, and 21 patients in PD group, for a closure rate of 40.4%. HR = 3.05; 95% CI: 1.79-5.19; P < 0.001). Both length of stay and costs of the treatment in the DLIST group were lower (54 days [interquartile range, IQR: 41-17] days vs. 112 days [IQR: 66-27] days, P = 0.005; and $18,721 [IQR: $14,982-4,960] vs. $40,840 [IQR: $20,932-50,529], P < 0.001).

CONCLUSION

Placement of DLIST might serve as an effective method for treating AD following rectal cancer surgery. In comparison with PD, it costs lower to apply DLIST in the treatment of AD and the length of stay is shorter.

Temporal determinants of tumour response to neoadjuvant rectal radiotherapy

Introduction

In locally advanced rectal cancer, longer delay to surgery after neoadjuvant radiotherapy increases the likelihood of histopathological tumour response. Chronomodulated radiotherapy in rectal cancer has recently been reported as a factor increasing tumour response to neoadjuvant treatment in patients having earlier surgery, with patients receiving a larger proportion of afternoon treatments showing improved response. This paper aims to replicate this work by exploring the impact of these two temporal factors, independently and in combination, on histopathological tumour response in rectal cancer patients.

Methods

A retrospective review of all patients with rectal adenocarcinoma who received long course (≥24 fractions) neoadjuvant radiotherapy with or without chemotherapy at a tertiary referral centre was conducted. Delay to surgery and radiotherapy treatment time were correlated to clinicopathologic characteristics with a particular focus on tumour regression grade. A review of the literature and meta-analysis were also conducted to ascertain the impact of time to surgery from preoperative radiotherapy on tumour regression.

Results

From a cohort of 367 patients, 197 patients met the inclusion criteria. Complete pathologic response (AJCC regression grade 0) was seen in 46 (23%) patients with a further 44 patients (22%) having at most small groups of residual cells (AJCC regression grade 1). Median time to surgery was 63 days, and no statistically significant difference was seen in tumour regression between patients having early or late surgery. There was a non-significant trend towards a larger proportion of morning treatments in patients with grade 0 or 1 regression (p = 0.077). There was no difference in tumour regression when composite groups of the two temporal variables were analysed. Visualisation of data from 39 reviewed papers (describing 27379 patients) demonstrated a plateau of response to neoadjuvant radiotherapy after approximately 60 days, and a meta-analysis found improved complete pathologic response in patients having later surgery.

Conclusions

There was no observed benefit of chronomodulated radiotherapy in our cohort of rectal cancer patients. Review of the literature and meta-analysis confirms the benefit of delayed surgery, with a plateau in complete response rates at approximately 60-days between completion of radiotherapy and surgery. In our cohort, time to surgery for the majority of our patients lay along this plateau and this may be a more dominant factor in determining response to neoadjuvant therapy, obscuring any effects of chronomodulation on tumour response. We would recommend surgery be performed between 8 and 11 weeks after completion of neoadjuvant radiotherapy in patients with locally advanced rectal cancer.

Short-course radiotherapy in stage IV rectal cancer with resectable disease

INTRODUCTION

Stage IV rectal cancer with resectable disease presents challenging issues, as the radical treatment of the whole disease is difficult. Surgery and chemotherapy (CT) play an unquestionable role, but the contribution of pelvic radiotherapy (RT) is not very clear.

METHODS

In 2009, we established a prospective treatment protocol that included CT, short-course preoperative radiotherapy (SCRT) with surgery of the primary tumour and all metastatic locations.

RESULTS

Forty patients were included. Eight (20%) patients did not receive CT due to significant comorbidities. Radical surgery treatment was possible in 22 (55%) patients. The mean follow-up was 42.81 months (3.63-105.97). Overall survival at 24 and 36 months was 71.4% and 58.2%, respectively. There was good local control of the disease, as 97.2% of pelvic surgeries were R0 and there were no local recurrences.

CONCLUSION

In stage IV with resectable metastatic disease, the proposed therapeutic regimen seems very appropriate in well selected patients able to tolerate the treatment. We bet on the role of pelvic RT, due to the good local control of the disease in our series.

The optimal timing for the interval to surgery after short course preoperative radiotherapy (5 ×5 Gy) in rectal cancer - are we too eager for surgery?

BACKGROUND

The improved overall survival (OS) after short course preoperative radiotherapy (SCPRT) using 5 × 5 Gy reported in the early rectal cancer trials could not be replicated in subsequent phase III trials. This original survival advantage is attributed to poor quality of surgery and the large differential in local recurrence rates, with and without SCPRT. Immuno-modulation during and after SCPRT and its clinical implications have been poorly investigated. We propose an alternative explanation for this survival benefit in terms of immunological mechanisms induced by SCPRT and the timing of surgery, which may validate the concept of consolidation chemotherapy.

MATERIAL AND METHODS

We reviewed randomized controlled trials (RCTs) and studies of SCPRT from 1985 to 2019. We aimed to examine the precise timing of surgery in days following SCPRT and identify evidence for immune modulation, neo-antigens and memory cell induction by radiation.

RESULTS

Considerable variability is reported in randomised trials for median overall treatment time (OTT) from start of SCPRT to surgery (8-14 days). Only three early trials showed a benefit in terms of OS from SCPRT, although the level of benefit in preventing local recurrence was consistent across all trials. Different patterns of immune effects are observed within days after SCPRT depending on the OTT, but human leukocyte antigen (HLA)-1 expression was not upregulated.

CONCLUSIONS

SCPRT has a substantial immune-stimulatory potential. The importance of the timing of surgery after SCPRT may have been underestimated. An optimal interval for surgery after 5 × 5 Gy may lead to better outcomes, which is possibly exploited in total neoadjuvant therapy schedules using consolidation chemotherapy. Individual patient meta-analyses from appropriate SCPRT trials examining outcomes for each day and prospective trials are needed to clarify the validity of this hypothesis. The interaction of SCPRT with tumour adaptive immunology, in particular the kinetics and timing, should be examined further.

MRI response rate after short-course radiotherapy on rectal cancer in the elderly comorbid patient: results from a retrospective cohort study

Background

The aim of the present study was to evaluate MRI response rate and clinical outcome of short-course radiotherapy (SCRT) on rectal cancer as an alternative to chemoradiotherapy in patients where downstaging is indicated.

Methods

A retrospective analysis was performed of a patient cohort with rectal carcinoma (cT1-4cN0-2 cM0–1) from a large teaching hospital receiving restaging MRI, deferred surgery or no surgery after SCRT between 2011 and 2017. Patients who received chemotherapy during the interval between SCRT and restaging MRI were excluded.

The primary outcome measure was the magnetic resonance tumor regression grade (mrTRG) at restaging MRI after SCRT followed by a long interval. Secondary, pathological tumor stage, complete resection rate and 1-year overall survival were assessed.

Results

A total of 47 patients (M:F = 27:20, median age 80 (range 53–88) years), were included. In 33 patients MRI was performed for response assessment 10 weeks after SCRT. A moderate or good response (mrTRG≤3) was observed in 24 of 33 patients (73%). While most patients (85%; n = 28) showed cT3 or cT4 stage on baseline MRI, a ypT3 or ypT4 stage was found in only 20 patients (61%) after SCRT (p <  0.01). A complete radiologic response (mrTRG 1) was seen in 4 patients (12%). Clinical N+ stage was diagnosed in n = 23 (70%) before SCRT compared to n = 8 (30%) post-treatment (p = 0.03).

After SCRT, 39 patients underwent deferred surgery (after a median of 14 weeks after start of SCRT) and a resection with complete margins was achieved in 35 (90%) patients. One-year overall survival after surgery was 82%. Complete pathological response was found in 2 patients (5%).

Conclusions

The use of SCRT followed by a long interval to restaging showed a moderate to good response in 73% and therefore can be considered as an alternative to chemoradiotherapy in elderly comorbid patients.

Dose-time fractionation schedules of preoperative radiotherapy and timing to surgery for rectal cancer

Chemoradiotherapy (CRT) is extensively used prior to surgery for rectal cancer to provide significantly better local control, but the radiotherapy (RT), as the other component of CRT, has been subject to less interest than the drug component in recent years. With considerable developments in RT, the use of advanced techniques, such as intensity-modulated radiotherapy (IMRT) in rectal cancer, is garnering more attention nowadays. The radiation dose can be better conformed to the target volumes with possibilities for synchronous integrated boost without increased complications in normal tissue. Hopefully, both local recurrence and toxicities can be further reduced. Although those seem to be of interest, many issues remain unresolved. There is no international consensus regarding the radiation schedule for preoperative RT for rectal cancer. Moreover, an enormous disparity exists regarding the RT delivery. With the advent of IMRT, variations will likely increase. Moreover, time to surgery is also quite variable, as it depends upon the indication for RT/CRT in the clinical practices. In this review, we discuss the options and problems related to both the dose-time fractionation schedule and time to surgery; furthermore, it addresses the research questions that need answering in the future.

Gastrointestinal Malignancies and the COVID-19 Pandemic: Evidence-Based Triage to Surgery

BACKGROUND

The COVID-19 pandemic has led to widespread cancelation of electively scheduled surgeries, including for colorectal, pancreatic, and gastric cancer. The American College of Surgeons and the Society of Surgical Oncology have released guidelines for triage of these procedures. We seek to synthesize available evidence on delayed resection and oncologic outcomes, while also providing a critical assessment of the released guidelines.

METHODS

A systematic review was conducted to identify literature between 2005 and 2020 investigating the impact of time to surgery on oncologic outcomes in colorectal, pancreatic, and gastric cancer.

RESULTS

For colorectal cancer, 1066 abstracts were screened and 43 papers were included. In primarily resected colon cancer, delay over 30 to 40 days is associated with lower survival. In rectal cancer, time to surgery over 7 to 8 weeks following neoadjuvant therapy is associated with decreased survival. Three hundred ninety-four abstracts were screened for pancreatic cancer and nine studies were included. Two studies demonstrate increased unexpected progression with delayed surgery over 30 days. Out of 633 abstracts screened for gastric cancer, six studies were included. No identified study demonstrated worse survival with increased time to surgery.

CONCLUSION

Moderate evidence suggests that delayed resection of colorectal cancer worsens survival; the impact of time to surgery on gastric and pancreatic cancer outcomes is uncertain. Early resection of gastrointestinal malignancies provides the best chance for curative therapy. During the COVID-19 pandemic, prioritization of procedures should account for available evidence on time to surgery and oncologic outcomes.

Drain fluid's pH predicts anastomotic leak in colorectal surgery: results of a prospective analysis of 173 patients

BACKGROUND

The early risk assessment of anastomotic leak (AL) after colorectal surgery is crucial. Several markers have been proposed, including peritoneal fluid's pH. Aim of the present study is to evaluate the role of drain fluid pH as predictor of AL.

METHODS

All patients undergoing colorectal surgery from January 2015 to December 2017 were considered eligible. Hartmann procedures, procedures including temporary ileostomy and emergency surgery were excluded. Drain fluid was submitted for pH and chemical-physical assessment on postoperative day 1 (POD1) and postoperative day 3 (POD3).

RESULTS

Out of 173 patients, those who developed AL showed a lower drain fluid's pH on POD1 and on POD3 compared to patients who did not (P<0.05). The plotted ROC curves identified 7.53 as pH cut-off on POD1 (AUC 0.80) and 7.21 on POD3 (AUC 0.86). With both the cut-offs, pH was an independent predictor of AL at multivariable analysis (P<0.001). pH<7.53 on POD1 and pH<7.21 on POD3 showed 93.75% sensitivity and 97% specificity respectively.

CONCLUSIONS

Drain fluid's pH on POD1 is useful to select patients who will not develop AL while on POD3 it might identify those requiring a more careful management.

Short-course radiotherapy with immediate or delayed surgery in rectal cancer: A meta-analysis

BACKGROUND

The safety and efficacy of preoperative short-course radiotherapy had been verified in rectal cancer. However, the timing of surgery after radiation had not been well defined. Thus, we performed this meta-analysis to compare the interval time of surgery after short-course radiotherapy in rectal cancer: immediate surgery (<4 weeks) vs delayed surgery (>4 weeks).

METHODS

We searched the PubMed, EMBASE, MEDLINE, and Cochrane Library database. The primary endpoints were survival rates and pathological outcomes, and the second endpoints included sphincter preservation rate, R0 resection rate and postoperative complications. RevMan 5.3 was used to calculate pooled risk ratio (RRs) and 95% confidence interval (CIs).

RESULTS

In total, 5 eligible studies including 1244 participants were identified. The delayed surgery group had a markedly higher pathological complete response rate [RR = 15.71, 95% CI (2.10, 117.30), P = 0.007] and downstaging rate [RR = 2.63, 95% CI (1.77, 3.90), P < 0.00001], a higher proportion of patients with adjuvant pathologic stage 0 + I disease [RR = 1.49, 95% CI (1.23, 1.81), P < 0.0001] and a lower incidence of postoperative complications [RR = 0.81, 95% CI (0.70, 0.95), P = 0.008] than did the immediate surgery group, but the survival rate, sphincter preservation rate and R0 resection rate were similar between the two groups.

CONCLUSION

Based on better pathologic outcomes and fewer postoperative complications, we recommended short-course radiotherapy with delayed surgery for more than 4 weeks.

Tumor response after long interval comparing 5x5Gy radiation therapy with chemoradiation therapy in rectal cancer patients

BACKGROUND

In the era of organ preserving strategies in rectal cancer, insight into the efficacy of preoperative therapies is crucial. The goal of the current study was to evaluate and compare tumor response in rectal cancer patients according to their type of preoperative therapy.

METHODS

All rectal cancer patients diagnosed between 2005 and 2014, receiving radiation therapy (RT, 5 × 5Gy; N = 764) or chemoradiation therapy (CRT; N = 5070) followed by total mesorectal excision after an interval of 5-15 weeks were retrieved from the nationwide Netherlands Cancer registry. Logistic regression was used for multivariable analysis.

RESULTS

Median age of patients treated with RT was 76 years (range 28-92) compared to 64 years (range 21-92) for patients treated with CRT (P < 0.001). Patients treated with RT had a significantly lower clinical stage (P < 0.001). A complete pathologic response (ypT0N0) was found in 9.3% of patients treated with RT, significantly less than in patients treated with CRT (17.5%; odds ratio [OR] 0.37, 95% confidence interval [CI] 0.24-0.57). A good response (ypT0-1N0) was observed in 17.5% of patients treated with RT and in 22.6% of patients treated with CRT (OR 0.70, 95% CI 0.51-0.95). Histological subtype, clinical stage and distance to anus were identified as independent predictors for tumor response.

CONCLUSIONS

Despite a more advanced clinical stage, complete pathologic response was more common in patients treated with CRT than in patients treated with RT. Prospective trials are needed to establish the differences in other outcome parameters, including the impact on organ preserving strategies.

Importance of the Circumferential Extent of Tumors and Clinical Lymph Node Status as Prognostic Factors after Preoperative Chemoradiotherapy and Surgery in Patients with Rectal Cancer

Aims and background

To evaluate the clinical factors that influence pathological and clinical outcomes after preoperative concurrent chemoradiotherapy in patients with rectal cancer.

Methods

Between 1999 and 2004, 121 patients with cT3-4 or node-positive rectal cancer received preoperative chemoradiotherapy and surgery. Preoperative radiation therapy with 45 Gy was delivered. Fluorouracil-based chemotherapy was administered to most of the patients.

Results

Pathological complete remission was 14.3% after preoperative chemoradiotherapy. More than 60% tumor circumferential extent was an independent adverse factor for complete remission (P = 0.011, HR 4.643, 95% CI 1.415–15.231). Local recurrence developed in 9.9% of the cases. Serum CEA level ≥5 ng/ml (P = 0.057, HR 3.022, 95% CI 0.967–9.441) and >60% circumferential extent of tumor (P = 0.064, HR 4.232, 95% CI 0.918–19.531) were marginal adverse factors for local recurrence. Five-year disease-free survival and overall survival were 72.2% and 86.6%, respectively. Disease-free survival was poor for patients with the lymph nodes ≥1 cm in diameter (P = 0.028), cN2 stage disease (P = 0.047) and >60% circumferential extent of tumor (P = 0.058). Multivariate analysis for disease-free survival showed that the lymph node size ≥1 cm was an adverse factor (P = 0.019, HR 2.380, 95% CI 1.115–4.906). Patients with >60% circumferential extent of tumor and cN2 stage had a more unfavorable survival than the other patients (disease-free survival, P = 0.018; overall survival, P = 0.015). Patients with >60% circumferential extent of tumor and/or lymph node ≥1 cm also had an unfavorable survival (disease-free survival, P = 0.016; overall survival, P = 0.049).

Conclusions

In rectal cancer, circumferential extent of tumor and clinical lymph node status were important factors for preoperative chemoradiotherapy and surgery. A further prospective study is needed to confirm and expand these findings.

Optimal Interval to Surgery After Neoadjuvant Chemoradiotherapy in Rectal Cancer: A Systematic Review and Meta-analysis

This study aimed to evaluate the influence of a waiting interval of ≥ 8 weeks between the end of preoperative neoadjuvant chemoradiotherapy (nCRT) and surgery on the outcomes of patients with locally advanced rectal cancer. We conducted a comprehensive literature review of retrospective and prospective studies from PubMed, Embase, and Cochrane Library databases to investigate the length of the preoperative nCRT-surgery waiting interval and outcomes in patients with locally advanced rectal cancer. The primary outcome measure was pathologic complete response (pCR) rate. Secondary outcome measures included overall survival, disease-free survival, operative time, and the incidence of local recurrence, postoperative complications, anastomotic leakage, and sphincter-preserving surgery. Standardized mean differences and risk ratios were calculated. Thirteen studies involving 19,652 patients were included. The meta-analysis demonstrated that pCR was significantly increased in patients with locally advanced rectal cancer and a waiting interval of ≥ 8 weeks between preoperative nCRT and surgery compared to a waiting interval of < 8 weeks, or a waiting interval of > 8 weeks compared to ≤ 8 weeks (risk ratio = 1.25; 95% confidence interval, 1.16-1.35; P < .0001). There were no significant differences in overall survival, disease-free survival, operative time, or incidence of local recurrence, postoperative complications, or sphincter-preserving surgery. This study revealed that performing surgery after a waiting interval of ≥ 8 weeks after the end of preoperative nCRT is safe and efficacious for patients with locally advanced rectal cancer, significantly improving pCR without increasing operative time or incidence of postoperative complications, compared to a waiting interval of ≤ 8 weeks.

Acute toxicity and surgical complications after preoperative (chemo)radiation therapy for rectal cancer in patients with inflammatory bowel disease

PURPOSE

Preoperative therapy reduces local recurrences and may facilitate surgery in rectal cancer patients. However, in patients with inflammatory bowel disease (IBD) this treatment is often withheld due to the perceived risk of excessive side-effects, even though evidence is limited. The purpose of this study is to investigate the effects of preoperative therapy on acute toxicity and post-operative complications in IBD patients with rectal cancer.

METHODS

The Dutch pathology registry (PALGA) was searched for patients with IBD and rectal cancer treated between January 1991 and May 2010. Histopathology and clinical charts were reviewed to confirm IBD diagnosis and evaluate clinical and pathological characteristics.

RESULTS

Out of 161 patients, 66 received preoperative therapy (41%), including short-course radiation therapy (SC-RT), long course radiation therapy (LC-RT), and chemoradiation therapy (CRT) in 32, 13, and 21 patients respectively. Grade≥3 acute toxicity occurred in 0 patients (0.0%), 1 patient (7.7%), and 6 patients (28.6%) respectively (p=0.004). Systemic corticosteroids were used by 10.5% of patients at time of treatment. Grade≥3 post-operative 30-day complication rate (28.1% overall) was not associated with type of preoperative therapy.

CONCLUSION

Results did not show excessive rates of toxicity or post-operative complications and support the use of standard preoperative therapies for rectal cancer (especially SC-RT) in IBD patients with relatively indolent disease. Caution is warranted in patients with active IBD, since the exact impact of active bowel inflammation could not be determined retrospectively. Prospective studies should investigate the influence of active IBD on acute and late toxicity in patients receiving pelvic irradiation.

Delaying surgery after neoadjuvant chemoradiotherapy improves prognosis of rectal cancer

AIM

To investigate the prognostic effect of a delayed interval between neoadjuvant chemoradiotherapy (CRT) and surgery in locally advanced rectal cancer.

METHODS

We evaluated 87 patients with locally advanced mid- or distal rectal cancer undergoing total mesorectal excision following an interval period after neoadjuvant CRT at Şişli Hamidiye Etfal Training and Research Hospital, Istanbul between January 2009 and January 2014. Patients were divided into two groups according to the interval before surgery: < 8 wk (group I) and ≥ 8 wk (group II). Data related to patients, cancer characteristics and pathological examination were collected and analyzed.

RESULTS

When the distribution of timing between group I (n = 45) and group II (n = 42) was viewed, comparison of interval periods (median ± SD) of groups showed a significant difference of as 5 ± 1.28 wk in group I and 10.1 ± 2.2 wk in group II (P < 0.001). The median follow-up period for all patients was 34.5 (9.9-81) mo. group II had significantly higher rates of pathological complete response (pCR) than group I had (19% vs 8.9%, P = 0.002). Rate of tumor regression grade (TRG) poor response was 44.4% in group I and 9.5% in group II (P < 0.002). A poor pathological response was associated with worse disease-free survival (P = 0.009). The interval time did not show any association with local recurrence (P = 0.79).

CONCLUSION

Delaying the neoadjuvant CRT-surgery interval may provide nodal down-staging, improve pCR rate, and decrease the rate of TRG poor response.

Optimal Timing to Surgery after Neoadjuvant Chemoradiotherapy for Locally Advanced Rectal Cancer

BACKGROUND

Neoadjuvant chemoradiotherapy (nCRT) has demonstrated proven benefit in tumor regression and improved long-term local control for patients with locally advanced rectal cancer. However, precise analysis of the optimal waiting time that maximizes oncologic benefits of nCRT has not been established.

STUDY DESIGN

The 2006-2012 National Cancer Data Base was queried for patients with stage II and III rectal adenocarcinoma who underwent nCRT followed by surgical resection. Time to surgery was defined as the difference between last date of radiotherapy and date of surgery. Primary study endpoints included resection margin positivity and pathologic downstaging. Multivariable regression modeling with restricted cubic splines was used to evaluate the adjusted association between time to surgery and our study endpoints, and to establish an optimal time threshold for surgery.

RESULTS

A total of 11,760 patients were included. Median time to surgery was 53 days (interquartile range [IQR] 43 to 63 days). After adjusting for patient demographic, clinical, tumor, and treatment characteristics, our model determined an inflection point at 56 days after end of radiotherapy associated with the highest likelihood of complete resection and pathologic downstaging. With adjustment, the risk of margin positivity was increased in those who underwent surgery after 56 days from end of radiotherapy (odds ratio [OR] 1.40, 95% CI 1.21 to 1.61, p < 0.001). The likelihood of downstaging was increasing up to 56 days after radiotherapy (≥56 days vs <56 days, OR 1.2, 95% CI 1.02 to 1.23, p = 0.01).

CONCLUSIONS

This study objectively determined the optimal time for surgery after completion of nCRT for rectal cancer based on completeness of resection and tumor downstaging. Eight weeks appears to be the critical threshold for optimal tumor response.

The timing of surgery after preoperative short-course S-1 chemoradiotherapy with delayed surgery for T3 lower rectal cancer

PURPOSE

The purpose of this study was to analyze the influence of variations in clinical practice regarding the timing of surgery with short-course chemoradiotherapy with delayed surgery (SCRT-delay) for lower rectal cancer.

METHODS

A total of 171 patients with T3 N0-2 lower rectal cancer treated with SCRT-delay (25 Gy/10 fractions/5 days (S-1); days 1-10) were retrospectively evaluated. The median waiting period of 30 days was used as a discriminator (group A: waiting period, ≤30 days; group B: waiting period, ≥31 days). Preoperative treatment responses and oncological outcomes were analyzed.

RESULTS

The mean waiting periods for groups A and B were 24.4 ± 5.3 and 41.4 ± 12.3 days, respectively. There were no statistically significant differences between the two groups in any of the clinical variables. The clinicopathological outcomes were as follows: T downstaging (43.5 vs 37.2 %; p = 0.400), negative yp N (67.1 vs 75.6 %; p = 0.218), pCR (7.1 vs 1.2 %; p = 0.119). The 5-year local recurrence-free survival (89.3 vs 87.6 %; p = 0.956), the recurrence-free survival (82.2 vs 78.8 %; p = 0.662), and the overall survival (88.5 vs 84.4 %; p = 0.741), all of which were similar between the two groups.

CONCLUSIONS

The longer waiting period did not increase the tumor downstaging and not improve the oncological outcomes for T3 lower rectal cancer treated with SCRT-delay. In addition, considering that the impaired leukocyte response occurred during the sub-acute period, any time after the sub-acute period (day 12) up to 30 days after radiotherapy would be a suitable waiting period.

Interval between neoadjuvant treatment and definitive surgery in locally advanced rectal cancer: impact on response and oncologic outcomes

PURPOSE

The optimal waiting period between neoadjuvant treatment completion and surgery in locally advanced rectal cancer (LARC) is controversial. The specific purpose of this study was to evaluate the effect of prolonging this interval on the pathologic response, postoperative morbidity, and long-term oncologic outcomes.

METHODS

Retrospective data analysis is reported from LARC patients who had been treated with chemoradiation followed by surgery and intra-operative radiotherapy, between February 1995 and December 2012. In total, two groups were studied, according to the time elapsed between neoadjuvant treatment and surgery: conventional interval (CI; <6 weeks) and delayed interval (DI; ≥6 weeks). Clinicopathological data related to tumor response, postoperative morbidity, and oncologic outcomes were compared.

RESULTS

This study included 335 consecutive LARC patients. There was a higher proportion of patients with clinical staging nodal involvement (cN+) in the DI group (76.6 vs. 64.1 %; p = 0.01). The pathologic complete response (pCR) was not significantly different among groups (8.8 vs. 12.1 %; p = 0.34). Longer intervals did not affect complication incidence or severity or hospital admission length. Certain postneoadjuvant tumor effect parameters were significantly increased in the DI group, including N-downstaging and T-downsizing. After a median follow-up of 71 months, patients in the DI group presented with superior 5-year overall survival (OS) (55.9 vs. 70.4 %, p = 0.014); however, no statistically significant differences were observed in 5-year disease-free survival (DFS) or 5-year local control (LC) (69.9 vs. 74.9 %, p = 0.223; 90.4 vs. 94.5 %, p = 0.123, respectively).

CONCLUSIONS

A modest surgical interval delay (≥6 weeks) did not increase postoperative complications and was identified as a favorable prognostic factor for OS, although no differences were observed in pCR, LC, or DFS. Innovative multidisciplinary strategies incorporating further time extension of the surgical interval can be safely explored.

Risk assessment on anastomotic leakage after rectal cancer surgery: an analysis of 753 patients

PURPOSE

To investigate the risk factors for anastomotic leakage (AL) after anterior resection for rectal cancer with a double stapling technique.

PATIENTS AND METHODS

Between January 2004 and December 2011, 753 consecutive patients in Jiangsu Cancer Hospital and Research Institute diagnosed with rectal cancer and undergoing anterior resection with a double stapling technique were recruited. All patients experienced a total mesorectal excision (TME) operation. Additionally, decrease of postoperative tumor supplied group of factors (TSGF), which have not been reported before, was proposed as a new indicator for AL. Univariate and multivariate analysis were performed to determine risk factors for AL.

RESULTS

AL was detected in 57 (7.6%) of 753 patients with rectal cancer. The diagnosis of anastomotic leakage was confirmed between the 6th and 12th postoperative day (POD; mean 8th POD). After univariate analysis and multivariate analysis, age (p<0.001), gender (p=0.002), level of anastomosis (p <0.001), preoperative body mass index (BMI) (p = 0.001) and reduction of TSGF in 5th POD was less than 10 μ/ml (p <0.001) were selected as 5 independent risk factors for AL. It was also indicated that a temporary defunctioning transverse ileostomy (p = 0.04) would decrease the occurrence of AL.

CONCLUSION

AL after anterior resection for rectal carcinoma is related to elderly status, low level site of the tumor (below the peritoneal reflection), being male, preoperative BMI and the decrease of TSGF in 5th POD is less than 10 m/ml. Preventive ileostomy is advisable after TME for low rectal tumors to prevent AL.

Neoadjuvant radiotherapy (5 × 5 Gy): immediate versus delayed surgery

GOALS

To evaluate the role of length of the interval between 5 × 5 Gy and surgery.

METHODS

PubMed was searched to perform a systematic review.

RESULTS

There were 10 studies on 5 × 5 Gy with delayed surgery (no of patients (n) = 1343), and six studies on 5 × 5 Gy with consolidation chemotherapy delivered over a long interval prior to surgery in a tight sequence (n = 244). In total, there were four randomized studies, five phase II studies, and seven retrospective studies. Trials that compared immediate with delayed surgery after 5 × 5 Gy showed a benefit in terms of lower rate of severe acute post-radiation toxicity (4.2 % absolute difference) in the immediate-surgery group. However, this benefit was counterbalanced by the increase in minor postoperative complications (13 % of absolute difference) in the group with immediate surgery compared with that with the delayed surgery. The pathological complete response (pCR) rate was about 10 % higher in the delayed-surgery group. There were no differences in sphincter preservation and R0 resection rate between the two groups. Small studies suggest no differences in the oncological outcomes. Regarding elderly patients who were unfit for chemotherapy, short-course radiotherapy with delayed surgery produced favourable outcomes for "unresectable" cancer or for small cancer after full-thickness local excision. A watch-and-wait policy in complete responders after short-course radiotherapy is feasible. A pCR of over 20 % was recorded after short-course radiotherapy and consolidation chemotherapy compared with about 10 % after 5 × 5 Gy and delayed surgery. Favourable outcomes after short-course radiotherapy and consolidation chemotherapy were observed in patients with potentially resectable stage IV disease.

CONCLUSIONS

Evidence showed that 5 × 5 Gy with delayed surgery can be used routinely for the management of elderly patients who are unfit for chemotherapy in case of "unresectable" cancer or early cancer prior to local excision. Short-course radiotherapy with consolidation chemotherapy is a promising treatment that can be used routinely for potentially resectable stage IV disease.

Optimal timing of surgery after neoadjuvant chemoradiation therapy in locally advanced rectal cancer

PURPOSE

The optimal time between neoadjuvant chemoradiotherapy (CRT) and surgery for rectal cancer has been debated. This study evaluated the influence of this interval on oncological outcomes.

METHODS

We compared postoperative complications, pathological downstaging, disease recurrence, and survival in patients with locally advanced rectal cancer who underwent surgical resection <8 weeks (group A, n = 105) to those who had surgery ≥8 weeks (group B, n = 48) after neoadjuvant CRT.

RESULTS

Of 153 patients, 117 (76.5%) were male and 36 (23.5%) were female. Mean age was 57.8 years (range, 28 to 79 years). There was no difference in the rate of sphincter preserving surgery between the two groups (group A, 82.7% vs. group B, 77.6%; P = 0.509). The longer interval group had decreased postoperative complications, although statistical significance was not reached (group A, 28.8% vs. group B, 14.3%; P = 0.068). A total of 111 (group A, 75 [71.4%] and group B, 36 [75%]) patients were downstaged and 26 (group A, 17 [16.2%] and group B, 9 [18%]) achieved pathological complete response (pCR). There was no significant difference in the pCR rate (P = 0.817). The longer interval group experienced significant improvement in the nodal (N) downstaging rate (group A, 46.7% vs. group B, 66.7%; P = 0.024). The local recurrence (P = 0.279), distant recurrence (P = 0.427), disease-free survival (P = 0.967), and overall survival (P = 0.825) rates were not significantly different.

CONCLUSION

It is worth delaying surgical resection for 8 weeks or more after completion of CRT as it is safe and is associated with higher nodal downstaging rates.

Surgical issues in locally advanced rectal cancer treated by preoperative chemoradiotherapy

The standard treatment for patients with locally advanced rectal cancer is preoperative chemoradiotherapy followed by total mesorectal excision. This approach is supported by randomized trials, but there are still many unanswered questions about the multimodal management of rectal cancer. In surgical terms, these include the optimal time interval between completion of chemoradiotherapy and surgery; adequate distal resection margin and circumferential radial margin; sphincter preservation; laparoscopic surgery; and conservative management, including a 'wait and see' policy and local excision. This review considers these controversial issues in preoperative chemoradiotherapy.

Delayed surgery for rectal cancer patients receiving neoadjuvant chemoradiotherapy: a promising method in its infancy

BACKGROUND

Neoadjuvant chemoradiotherapy (nCRT) is used to downstage locally advanced rectal cancer before surgery. Accumulating data suggest that tumor response to nCRT is time dependent. A delay between nCRT and surgery may increase the proportion of patients that achieve a favorable response. However, delayed surgery beyond 6-8 weeks may increase the technical difficulty, and the risks of surgical complications and recurrence or metastasis. This article briefly reviews the relevant literature to evaluate the efficiency and safety of delayed surgery.

METHODS

Two non-cohort studies and 10 cohort studies were reviewed. The results were analyzed and the limitations discussed.

RESULTS

Although debatable, the findings of the included studies are promising. Delayed surgery may increase the proportion of favorable tumor response without compromising prognosis. However, most of the studies were retrospective, which introduces bias into the evaluation.

CONCLUSION

Delayed surgery is potentially useful, but this needs to be verified by further well-designed prospective trials.

Multimodal treatment strategies for locally advanced rectal cancer

This review outlines the important multimodal treatment issues associated with locally advanced rectal cancer. Changes to chemotherapy and radiation schema, as well as modern surgical approaches, have led to a revolution in the management of this disease but the morbidity and mortality remains high. Adequate treatment is dependent on precise preoperative staging modalities. Advances in staging via endorectal ultrasound, computed tomography, MRI and PET have improved pretreatment triage and management. Important prognostic factors and their impact for this disease are under investigation. Here we discuss the different treatment options including modern tumor-related surgical approaches, neoadjuvant as well as adjuvant therapies. Further clinical progress will largely depend on the broader implementation of multidisciplinary treatment strategies following the principles of evidence-based medicine.

Impact of interval between neoadjuvant chemoradiotherapy and TME for locally advanced rectal cancer on pathologic response and oncologic outcome

BACKGROUND

The interval between neoadjuvant chemoradiotherapy and surgery for rectal cancer has arbitrarily been set at 6-8 weeks. However, tumor regression is variable. This study aimed to evaluate whether the interval between neoadjuvant therapy and surgery had an impact on pathologic response and on surgical and oncologic outcome.

METHODS

A total of 356 consecutive patients with clinical stage II and III rectal adenocarcinoma were identified. Median age was 63 years, and 65 % were men. All patients received neoadjuvant chemoradiotherapy (45 Gy) with a continuous infusion of 5-fluorouracil. Data on neoadjuvant-surgery interval, type of surgery, pathology, postoperative complications, length of hospital stay, disease recurrence, and survival were reviewed. Patients were divided into two groups according to the interval between neoadjuvant therapy and surgery: ≤ 7 weeks (short interval, n = 201) and >7 weeks (long interval, n = 155).

RESULTS

The complete pathologic response rate was 21 %. It was significantly higher after a longer interval (28 %) than after a shorter interval (16 %, p = 0.006). A longer interval did not affect morbidity or length of hospital stay. After a median follow-up of 4.9 years, the 5-year cancer-specific survival rate was 83 % in the short-interval group versus 91 % in the long-interval group (p = 0.046), and the free-from-recurrence rate was 73 versus 83 %, respectively (p = 0.026).

CONCLUSIONS

In this retrospective analysis, there seems to be an association between a longer interval after neoadjuvant chemoradiotherapy and complete pathologic response without affecting postoperative morbidity and length of hospital stay, and with no detrimental effect on oncologic outcome.

Extended surgery and pelvic exenteration for locally advanced rectal cancer. What are the limits?

Historically, locally advanced rectal cancers with invasion of tumor into adjacent organs (T4 N1, 2 tumors) have been considered poor prognosis cancers treated with palliative intent. However with the advent of multi-modality therapy and improvement in surgical reconstructive techniques, extended resections for rectal tumors are possible with acceptable patient morbidity and excellent oncological outcomes.

Postoperative complications following surgery for rectal cancer

OBJECTIVE

This systematic review was designed to determine postoperative complication rates of radical surgery for rectal cancer (abdominal perineal resection and anterior resection).

SUMMARY OF BACKGROUND DATA

Lack of accepted complication rates for rectal cancer surgery may hinder quality improvement efforts and may impede the conception of future studies because of uncertainty regarding the expected event rates.

METHODS

All prospective studies of rectal cancer receiving radical surgery published between 1990 and August 2008 were obtained by searching Ovid MEDLINE, EMBASE, as well as ASCO GI, CAGS, and ASCRS meeting abstracts between 2004 and 2008. There was no language restriction. The outcomes extracted were anastomotic leak, pelvic sepsis, postoperative death, wound infection, and fecal incontinence. Summary complication rates were obtained using a random effects model; the Z-test was used to test for study heterogeneity.

RESULTS

Fifty-three prospective cohort studies and 45 randomized controlled studies with 36,315 patients (24,845 patients had an anastomosis) were eligible for inclusion. Most of the studies found were based in continental Europe (58%), followed by Asia (25%), United Kingdom (10%), North America (5%), and Australia/New Zealand. The anastomotic leak rate, reported in 84 studies, was 11% (95% CI: 10, 12); the pelvic sepsis rate, in 29 studies, was 12% (9, 16); the postoperative death rate, in 75 studies, was 2% (2, 3); and the wound infection rate, in 50 studies, was 7% (5, 8). Fecal incontinence rates were reported in too few studies and so heterogeneously that numerical summarization was inappropriate. Year of publication, use of preoperative radiation, use of laparoscopy, and use of protecting stoma were not significant variables, but average age, median tumor height, and method of detection (clinical vs. radiologic) showed significance to explain heterogeneity in anastomotic leak rates. Year of publication, study origin, average age, and use of laparoscopy were significant, but median tumor height and preoperative radiation use were not significant in explaining heterogeneity among observed postoperative death rates. With multivariable analysis, only average age for anastomotic leak and year of publication for postoperative death remained significant.

CONCLUSIONS

Benchmark complication rates for radical rectal cancer surgery were obtained for use in sample size calculations in future studies and for quality control purposes. Postoperative death rates showed improvement in recent years.

The relationship of histological tumor regression grade (TRG) and two different time intervals to surgery following radiation therapy for locally advanced rectal cancer

BACKGROUND

The objective of this study was to assess the effect of two different time intervals between radiation therapy and surgery for rectal cancer on the histological tumor regression grade (TRG) in the resected specimen.

METHODS

Between 1995 and 2000, patients undergoing preoperative radiation therapy and TME for locally advanced (T3N0 and T3N1) mid and low rectal tumors treated in the VU University Medical Center or the Zaans Medical Center were entered into this study. All patients received identical radiation treatment (5 x 5 Gy) in the VU University medical center and were subsequently operated on within 2 weeks in the Zaans Medical Center (SI group) and after 6-8 weeks in the VU University Medical Center (LI group). All available histological material was reevaluated for TRG and correlated to survival.

RESULTS

Sixty-seven patients were included in the present study, 28 in the LI group and 39 in the SI group. Patient gender was comparable for both groups with 21 (75%) male patients in the LI group versus 26 (67%) male patients in the SI group (p = 0.46). A T3N0 preoperative tumor stage was found in 21 (75%) patients in the LI group and in 33 (85%) patients in the SI group (p = 0.36). All tumors were histologically proven adenocarcinoma. Patients in the SI group were significantly older (67 vs. 58 years). In the LI group, a significantly more pronounced histological tumor regression was found. A complete response (TRG1), combined with a near complete histological response (TRG 2), were present in 12 patients in the LI group and in four patients in the SI group (p = 0.002). Radicality of resection was comparable for both groups. With a follow-up of over 60 months, there were no statistically significant differences between the SI and LI groups regarding local control, overall, or disease-free survival.

CONCLUSION

Although histological tumor regression is significantly more pronounced following a long interval between radiation therapy and surgery, in the present study, this is not reflected in a better radical resection rate, local control or better overall and disease-free survival.

Optimal surgery time after preoperative chemoradiotherapy for locally advanced rectal cancers

OBJECTIVE

To evaluate the effect of the time interval between chemoradiotherapy (CRT) and surgery on CRT response and surgical outcomes.

SUMMARY BACKGROUND DATA

Although preoperative CRT is a standard component of multimodal treatment for locally advanced rectal cancers, the optimal time for surgery after CRT has yet to be established. This study analyzed outcomes in 397 prospectively enrolled patients with locally advanced rectal cancer who underwent fractionated CRT involving 50.4 Gy radiotherapy followed by surgical resection between 4 and 8 weeks later.

METHODS

Patients were divided into 2 groups according to the time that elapsed between CRT and surgery: group A (28-41 day interval) and group B (42-56 day interval). CRT responses and surgical outcomes were analyzed.

RESULTS

Of the 397 patients, 217 (54.7%) were in group A and 180 (45.3%) in group B. The 2 groups were similar in terms of pretreatment characteristics other than a slight difference in mean age (A: 55.3 years vs. B: 57.5 years, P = 0.042). Analysis of CRT responses showed that the 2 groups were similar in terms of T-level downstaging rate (A: 47.5% vs. B: 44.4%, P = 0.548), volume reduction rate (A: 34.6% vs. B: 34.2%, P = 0.870) and complete response rate (A: 13.8% vs. B: 15.0%, P = 0.740). Analysis of surgical outcomes showed that the 2 groups were also similar in terms of sphincter-preservation rate (A: 83.9% vs. B: 82.2%, P = 0.688) and anastomosis-related complication rate (A: 5.5% vs. B: 3.9%, P = 0.453). The median follow-up period was 31 months (range, 5-63), and both groups showed similar local recurrence-free survival rates (P = 0.1165).

CONCLUSION

The present findings suggest that compared with a 4 to 6 week interval, delaying surgery for 6 to 8 weeks after completion of fractionated radiotherapy with concurrent chemotherapy does not improve CRT response or the sphincter-preservation rate, and does not decrease morbidity or local recurrence.

Long-term oncologic results of patients with distal rectal cancer treated by local excision with or without adjuvant treatment

AIM

The aim of this study is to review long-term oncologic results of local excision (LE) and to investigate the validity and feasibility of LE as a treatment option for distal rectal cancer.

MATERIALS AND METHODS

Seventy-six patients who underwent LE for distal rectal adenocarcinoma with curative intent from 1991 to 2000 at Severance Hospital Yonsei University Medical Center, Seoul, Korea were enrolled in this study.

RESULTS

Preoperative transrectal ultrasonography revealed 3 cases of uT0, 55 cases of uT1 and 18 cases of uT2. Postoperative pathologic examination revealed 10 cases of pT0 (where no residual cancer cells remained), 11 cases of pTis, 37 cases of pT1, 16 cases of pT2, and 2 cases of pT3. Eleven out of 37 patients with pT1 tumors received adjuvant radiation therapy. Among 16 patients with pT2 tumor, 7 undertook salvage operation and 8 received adjuvant therapy. The median follow-up period was 84.9 months. Local recurrence was observed in six patients. The 5-year local recurrence-free survival rate (LFS) was 89.4% in the pT1 group and 75.0% in the pT2 group (p = 0.012). Among the patients with pT1 cancer, those who received adjuvant radiation therapy demonstrated a 5-year LFS of 100%, compared to those who did not, 76.0% (p = 0.038).

CONCLUSION

Our results imply a potential role of LE and adjuvant radiation as an option for the treatment of distal rectal cancer, and that even for pT1 carcinoma, LE alone might not be a valid modality.