Management of Complete Response After Chemoradiation in Rectal Cancer

Surveillance strategies following curative resection and non-operative approach of rectal cancer: How and how long? Review of current recommendations

Different follow-up strategies are available for patients with rectal cancer following curative treatment. A combination of biochemical testing and imaging investigation, associated with physical examination are commonly used. However, there is currently no consensus about the types of tests to perform, the timing of the testing, and even the need for follow-up at all has been questioned. The aim of this study was to review the evidence of the impact of different follow-up tests and programs in patients with non-metastatic disease after definitive treatment of the primary. A literature review was performed of studies published on MEDLINE, EMBASE, the Cochrane Library and Web of Science up to November 2022. Current published guidelines from the most authoritative specialty societies were also reviewed. According to the follow-up strategies available, the office visit is not efficient but represents the only way to maintain direct contact with the patient and is recommended by all authoritative specialty societies. In colorectal cancer surveillance, carcinoembryonic antigen represents the only established tumor marker. Abdominal and chest computed tomography scan is recommended considering that the liver and lungs are the most common sites of recurrence. Since local relapse in rectal cancer is higher than in colon cancer, endoscopic surveillance is mandatory. Different follow-up regimens have been published but randomized comparisons and meta-analyses do not allow to determine whether intensive or less intensive follow-up had any significant influence on survival and recurrence detection rate. The available data do not allow the drawing of final conclusions on the ideal surveillance methods and the frequency with which they should be applied. It is very useful and urgent for clinicians to identify a cost-effective strategy that allows early identification of recurrence with a special focus for high-risk patients and patients undergoing a “watch and wait” approach.

Short-term outcomes of robotic-assisted surgery following neoadjuvant chemotherapy for lower rectal cancer

INTRODUCTION

There have been reports about robotic surgery for rectal cancer with chemoradiotherapy (CRT), but only a few studies have compared the use of robotic surgery with and without neoadjuvant chemotherapy (NAC). The aim of our study was to compare the perioperative outcomes of robotic surgery with and without NAC for lower rectal cancer and to examine the effects of NAC on robotic surgery.

METHODS

From January 2016 to July 2021, we compared the short-term outcomes of 45 patients who did not undergo NAC and 55 patients who underwent NAC.

RESULTS

The rate of sphincter-preserving surgeries was higher in the NAC group than in the non-NAC group (P = .024). The total operative time was significantly longer in the NAC group than in the non-NAC group (P < .001). The rate of lateral lymph node dissection was significantly higher in the NAC group than in the non-NAC group (P < .001). No significant differences were identified in the rate of incisional surgical site infections (SSI), organ/space SSI postoperative bleeding, small bowel obstruction, anastomotic leakage, urinary dysfunction, or urinary infections between the groups. There were eight incidences of lateral lymph node metastasis (15%) and two cases with positive resection margins (4.0%) in the NAC group.

CONCLUSIONS

Robotic surgery after NAC has few complications and a higher sphincter-preserving rate that without NAC.

The "Immunoscore" in rectal cancer: could we search quality beyond quantity of life?

Because of the function and anatomical environment of the rectum, therapeutic strategies for local advanced rectal cancer (LARC) must deal with two challenging stressors that are a high-risk of local and distal recurrences and a high-risk of poor quality of life (QoL). Over the last three decades, advances in screening tests, therapies, and combined-modality treatment options and strategies have improved the prognosis of patients with LARC. However, owing to the heterogeneous nature of LARC and genetic status, the patient may not respond to a specific therapy and may be at increased risk of side-effects without the life-prolonging benefit. Indeed, each therapy can cause its own side-effects, which may worsen by a combination of treatments resulting in long-term poor QoL. In LARC, QoL has become even more essential with the increasing incidence of rectal cancer in young individuals. Herein, we analyzed the value of the Immunoscore-Biopsy (performed on tumor biopsy at diagnosis) in predicting outcomes, alone or in association with clinical and imaging data, for each therapy used in LARC.

"Watch and wait" approach in rectal cancer patients following complete clinical response to neoadjuvant chemoradiotherapy does not compromise oncologic outcomes

BACKGROUND/AIMS

Although standart treatment for non-metastatic locally advanced rectal cancer includes neoadjuvant chemoradiation followed by surgical resection, patients who have achieved complete clinical response can be followed up without surgery.

MATERIALS AND METHODS

Between 2010 and 2016, 61 patients received neoadjuvant chemoradiotherapy for low rectal cancer. Those patients who achieved clinical complete response were included in the "watch and wait" protocol and did not receive surgery. The remaining patients underwent radical surgery and some of these were diagnosed as having complete response pathologically. This study compared the oncological results of clinically complete responders with those patients defined as pathologically tumor-free.

RESULTS

Seven patients who received neoadjuvant chemoradiotherapy were re-staged as having complete clinical response and included in the "watch and wait" approach protocol. The 5-year disease free survival was 100%. Mean follow-up was 63 months and the mean age was 57.3. Fifty-four patients underwent radical surgery and 7 of them were diagnosed as having pathological complete response. The 5-year survival was 100%. Mean follow-up was 56 months and the mean age was 50.6. All patients except one are alive without tumor recurrence in the surgery group. However, those who received surgery experienced significant morbidities due to their surgery.

CONCLUSION

The oncological results of the "watch and wait" approach patients were no different from the patients who received radical surgery and were diagnosed as having pathological complete response. Those patients in particular who required abdomino-perineal resection before chemoradiation should be informed about this approach if they have achieved complete response clinically.

T3 subclassification using the EMD/mesorectum ratio predicts neoadjuvant chemoradiation outcome in T3 rectal cancer patients

OBJECTIVE

To evaluate the feasibility of the EMD (extramural depth)/mesorectum ratio as a marker for T3 rectal cancer and its ability to predict tumour response to neoadjuvant chemoradiation and survival.

METHODS

From 2010 to 2016, 284 T3 rectal cancer patients who underwent high resolution MRI before neoadjuvant chemoradiation were enrolled. The EMD was defined as the distance from the outer edge of the muscularis propria to the outermost edge of the tumour. The measurement of the tumour EMD and mesorectum was in the same layer and their ratio was calculated. Receiver operating characteristic analysis and relative area under the curve statistics were used to choose the cut-off value. The association of the EMD/mesorectum ratio and other MRI or clinical factors with the tumour regression grade (TRG) was analysed. Cox regression analysis was used to estimate independent risk factors for disease-free survival (DFS) and overall survival (OS).

RESULTS

The mean EMD/mesorectum ratio was 0.47 ± 0.3. We chose an EMD/mesorectum ratio of 0.5 in further analyses after receiver operating characteristic analysis. Of 284 patients, 177 (62.3%) had an EMD/mesorectum ratio ≤ 0.5. Patients with an EMD/mesorectum ratio ≤ 0.5 had a higher TRG 0-1 rate than patients with a ratio >0.5 (53.1% vs 36.4%, p = 0.006). A multivariate analysis identified that an EMD/mesorectum ratio >0.5 [hazard ratio (HR) 2.020; p = 0.028] and ypTNM II-III (HR 3.550; p = 0.017) were independent prognostic factors to indicate decreased DFS. For OS, only patients with TRG 2-3 had decreased OS compared with patients with TRG 0-1 (HR 2.959; p = 0.035).

CONCLUSION

When the EMD/mesorectum ratio was applied to categorize T3 rectal cancer patients, the ratio of 0.5 can be used as a cut-off value for T3 rectal cancer. Patients with a ratio ≤ 0.5 had a higher response rate and better DFS. However, further validation is needed in a larger sample of patients. Advances in knowledge: The EMD/mesorectum ratio may serve to predict tumour response to neoadjuvant chemoradiation and survival in T3 rectal cancer patients.

Validation of a rectal cancer outcome prediction model with a cohort of Chinese patients

The risk of local recurrence (LR), distant metastases (DM) and overall survival (OS) of locally advanced rectal cancer after preoperative chemoradiation can be estimated by prediction models and visualized using nomograms, which have been trained and validated in European clinical trial populations. Data of 277 consecutive locally advanced rectal adenocarcinoma patients treated with preoperative chemoradiation and surgery from Shanghai Cancer Center, were retrospectively collected and used for external validation. Concordance index (C-index) and calibration curves were used to assess the performance of the previously developed prediction models in this routine clinical validation population. The C-index for the published prediction models was 0.72 ± 0.079, 0.75 ± 0.043 and 0.72 ± 0.089 in predicting 2-year LR, DM and OS in the Chinese population, respectively. Kaplan-Meier curves indicated good discriminating performance regarding LR, but could not convincingly discriminate a low-risk and medium-risk group for distant control and OS. Calibration curves showed a trend of underestimation of local and distant control, as well as OS in the observed data compared with the estimates predicted by the model.

In conclusion, we externally validated three models for predicting 2-year LR, DM and OS of locally advanced rectal cancer patients who underwent preoperative chemoradiation and curative surgery with good discrimination in a single Chinese cohort. However, the model overestimated the local control rate compared to observations in the clinical cohort. Validation in other clinical cohorts and optimization of the prediction model, perhaps by including additional prognostic factors, may enhance model validity and its applicability for personalized treatment of locally advanced rectal cancer.

The role of tissue diagnosis prior to neoadjuvant chemoradiotherapy for locally advanced rectal cancer

AIM

Neoadjuvant chemoradiotherapy is the standard of care for locally advanced rectal cancer, with diagnostic work-up routinely including a biopsy confirming invasive carcinoma. For the occasional patient where initial biopsies reveal only dysplasia, or even normal epithelium, repeat biopsy is currently advised, but this may delay therapy and repeat biopsy has potential adverse effects. The study aimed to determine, in the setting of clinical findings and imaging demonstrating locally advanced rectal cancer, whether the absence of a tissue diagnosis prior to commencing chemoradiation compromises patient outcome.

METHOD

A review was conducted of our database, including comprehensive treatment and outcome details, in which consecutive patients with colorectal cancer have been enrolled since 1997 at a single institution. All records for patients who received neoadjuvant chemoradiotherapy for locally advanced rectal cancer were reviewed to identify patients for whom treatment was initiated before a tissue diagnosis was obtained, and to assess any consequences of this.

RESULTS

Of 254 patients who had received neoadjuvant treatment for rectal cancer, 16 (6.3%) were found to have had neoadjuvant therapy without a tissue diagnosis of invasive cancer. Compared with cases where a tissue diagnosis had been obtained, median age (59 vs 63 years, P = 0.497), sex (75% vs 71.3% male, P = 0.955) and tumour location (56.3% vs 73.5% < 8 cm, P = 0.230) were similar. Of these, 14 (87.5%) had adenocarcinoma identified on histopathology review of the surgical specimen. Three patients were considered to have had complete pathological responses with mucin lakes within the muscularis propria (n = 2) or lymph nodes (n = 1) or fibrosis (n = 3). One of these had no mucin evident and only fibrosis; thus final pathological proof of invasive cancer was present in 15 (93.5%) patients. There were no local recurrences, but three of the 16 (18.8%) cases developed distant recurrence.

CONCLUSION

For the small number of cases without a confirmatory tissue diagnosis before chemoradiation, no adverse consequences were identified. In particular the initial diagnosis was confirmed in 15 out of 16 cases following pathological examination of the operative specimen. We would suggest that, where clinical and radiological features support a diagnosis of locally advanced rectal cancer, proceeding directly to neoadjuvant chemoradiotherapy in the absence of a biopsy demonstrating invasive cancer may not be unreasonable, particularly where repeat biopsy would delay the commencement of treatment.

Outcomes in non-metastatic colorectal cancer

The measurement of outcomes in non-metastatic colon and rectal cancer patients is a multi-dimensional endeavor involving prediction tools, standard of care, and best treatment guidelines. Socioeconomic, demographic, and racial impacts on outcome must be carefully considered. Consideration must also be given to measures of cost, quality, and healthcare delivery in response to initiatives meant to optimize patient health while maintaining quality of life.

Organ preservation in rectal cancer patients following complete clinical response to neoadjuvant chemoradiotherapy: Long-term results in three patients

Rectal cancer patients following complete clinical response to neoadjuvant chemoradiotherapy (CRT) can be followed up without surgery. Those patients in particular who needed abdominoperineal resection before CRT choose the follow-up protocol, should they be given the necessary information. The purpose of this study was to demonstrate the long-term follow-up results of patients following neoadjuvant CRT without surgery.