Delayed versus immediate surgery following short-course neoadjuvant radiotherapy in resectable (T3N0/N+) rectal cancer

Rectal MRI Interpretation After Neoadjuvant Therapy

In recent years, several key advances in the management of locally advanced rectal cancer have been made, including the implementation of total mesorectal excision as the standard surgical approach; use of neoadjuvant chemoradiotherapy in selected patients with a high risk of local recurrence, and finally, adoption of organ preservation strategies, through either local excision or nonoperative management in selected patients with clinical complete response following neoadjuvant chemoradiotherapy. This review aims to shed light on the role of rectal MRI in the assessment of treatment response after neoadjuvant therapy, which is especially important given the growing feasibility of nonoperative management. First, an overview of current neoadjuvant therapies and response assessment based on digital rectal examination, endoscopy, and MRI will be provided. Second, the use of a high-quality restaging rectal MRI protocol will be presented. Third, a step-by-step approach to assessing treatment response on restaging rectal MRI following neoadjuvant treatment will be outlined, acknowledging challenges faced by radiologists during MRI interpretation. Finally, research related to response assessment will be discussed. LEVEL OF EVIDENCE: 4 TECHNICAL EFFICACY: Stage 3.

Evaluating potential delays and outcomes of patients undergoing surgical resection for locally advanced and recurrent colorectal cancer during a pandemic

INTRODUCTION

The COVID-19 pandemic resulted in a significant disruption of colorectal cancer (CRC) care pathways. This study evaluates the management and outcomes of patients with primary locally advanced or recurrent CRC during the pandemic in a single tertiary referral centre.

METHODS

Patients undergoing elective surgery for advanced or recurrent CRC with curative intent between March 2020 and March 2021 were identified. Following first multidisciplinary team discussion patients were broadly classified into two groups: straight to surgery (n=22, 45%) or neoadjuvant therapy followed by surgery (n=27, 55%). Primary outcome was COVID-19-related complication rate.

RESULTS

Forty-nine patients with a median age of 66 years (interquartile range: 54-73) were included. No patients developed a COVID-19 infection or related complication during hospital admission. Significant delays were identified in the treatment pathway of patients in the straight to surgery group, mostly due to delays in referral from external centres. Nine of 22 patients in the straight to surgery group had evidence of tumour progression compared with 3 of 27 in the neoadjuvant group (p=0.015839). Seven of 27 patients in the neoadjuvant group showed evidence of tumour regression. During the study, surgical waiting times were reduced, and more operations were performed during the second wave of COVID-19.

CONCLUSION

This study suggests that it is possible to mitigate the risks of COVID-19-related complications in patients undergoing complex surgery for locally advanced and recurrent CRC. Delay in surgical intervention is associated with tumour progression, particularly in patients who may not have neoadjuvant therapy. Efforts should be made to prioritise resources for patients requiring time-sensitive surgery for advanced and recurrent CRC.

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.

Standard (8 weeks) vs long (12 weeks) timing to minimally-invasive surgery after NeoAdjuvant Chemoradiotherapy for rectal cancer: a multicenter randomized controlled parallel group trial (TiMiSNAR)

BACKGROUND

The optimal timing of surgery in relation to chemoradiation is still controversial. Retrospective analysis has demonstrated in the recent decades that the regression of adenocarcinoma can be slow and not complete until after several months. More recently, increasing pathologic Complete Response rates have been demonstrated to be correlated with longer time interval. The purpose of the trial is to demonstrate if delayed timing of surgery after neoadjuvant chemoradiotherapy actually affects pathologic Complete Response and reflects on disease-free survival and overall survival rather than standard timing.

METHODS

The trial is a multicenter, prospective, randomized controlled, unblinded, parallel-group trial comparing standard and delayed surgery after neoadjuvant chemoradiotherapy for the curative treatment of rectal cancer. Three-hundred and forty patients will be randomized on an equal basis to either robotic-assisted/standard laparoscopic rectal cancer surgery after 8 weeks or robotic-assisted/standard laparoscopic rectal cancer surgery after 12 weeks.

DISCUSSION

To date, it is well-know that pathologic Complete Response is associated with excellent prognosis and an overall survival of 90%. In the Lyon trial the rate of pCR or near pathologic Complete Response increased from 10.3 to 26% and in retrospective studies the increase rate was about 23-30%. These results may be explained on the relationship between radiation therapy and tumor regression: DNA damage occurs during irradiation, but cellular lysis occurs within the next weeks. Study results, whether confirmed that performing surgery after 12 weeks from neoadjuvant treatment is advantageous from a technical and oncological point of view, may change the current pathway of the treatment in those patient suffering from rectal cancer.

TRIAL REGISTRATION

ClinicalTrials.gov NCT3465982.

A Concise Review of Pelvic Radiation Therapy (RT) for Rectal Cancer with Synchronous Liver Metastases

Background and Objective

Colorectal cancer is a major health concern as a very common cancer and a leading cause of cancer-related mortality worldwide. The liver is a very common site of metastatic spread for colorectal cancers, and, while nearly half of the patients develop metastases during the course of their disease, synchronous liver metastases are detected in 15% to 25% of cases. There is no standardized treatment in this setting and no consensus exists on optimal sequencing of multimodality management for rectal cancer with synchronous liver metastases.

Methods

Herein, we review the use of pelvic radiation therapy (RT) as part of potentially curative or palliative management of rectal cancer with synchronous liver metastases.

Results

There is accumulating evidence on the utility of pelvic RT for facilitating subsequent surgery, improving local tumor control, and achieving palliation of symptoms in patients with stage IV rectal cancer. Introduction of superior imaging capabilities and contemporary RT approaches such as Intensity Modulated Radiation Therapy (IMRT) and Image Guided Radiation Therapy (IGRT) offer improved precision and toxicity profile of radiation delivery in the modern era.

Conclusion

Even in the setting of stage IV rectal cancer with synchronous liver metastases, there may be potential for extended survival and cure by aggressive management of primary tumor and metastases in selected patients. Despite lack of consensus on sequencing of treatment modalities, pelvic RT may serve as a critical component of multidisciplinary management. Resectability of primary rectal tumor and liver metastases, patient preferences, comorbidities, symptomatology, and logistical issues should be thoroughly considered in decision making for optimal management of patients.

Is long interval from neoadjuvant chemoradiotherapy to surgery optimal for rectal cancer in the era of intensity-modulated radiotherapy?: a prospective observational study

OBJECTIVES

To evaluate the impact of interval between neoadjuvant chemoradiotherapy (NACRT) and surgery on therapeutic and adverse effects of surgery, and long-term outcome of patients with locally advanced rectal cancer (RC), in the era of intensity-modulated radiotherapy (IMRT).

PATIENTS AND METHODS

Patients diagnosed with stage II-III RC and treated with IMRT-based NACRT followed by radical surgery were enrolled consecutively from April 2011 to March 2014. The data of all the patients were collected prospectively and grouped according to their NACRT-to-surgery interval. The therapeutic and adverse effects of surgery, and survivals were compared between the patients with interval ≤7 weeks and those with interval ≥8 weeks.

RESULTS

A total of 231 patients were eligible for analysis, including 106 cases with interval ≤7 weeks and 125 cases with interval ≥8 weeks. The therapeutic and adverse effects of surgery were similar between these two groups of patients. However, interval ≥8 weeks appeared to lead to poorer overall, distant-metastasis-free and disease-free survivals, compared with interval ≤7 weeks. The HRs were 1.805, 1.714, and 1.796 (P-values were 0.045, 0.049, and 0.028), respectively.

CONCLUSION

For patients with locally advanced RC, a long NACRT-to-surgery interval might bring a potential risk of increased distant metastasis rather than a better tumor regression in the era of IMRT.