Preoperative therapy for lower rectal cancer and modifications in distance from anal sphincter

Efficacy and safety of preoperative chemoradiotherapy with S-1 for advanced rectal cancer: a phase II study

Background

Preoperative chemoradiotherapy (CRT) for patients with rectal cancer is not yet established in Japan. We aimed to evaluate the efficacy and safety of preoperative CRT with S-1, a fixed-dose combination of tegafur, gimeracil, and oteracil potassium.

Materials and methods

We conducted a prospective, interventional, non-randomized single-center study. Radiotherapy was administered at a total dose of 45 Gy (1.8 Gy in 25 fractions) for five weeks. S-1 was administered orally for nine weeks (five weeks during and four weeks after radiotherapy) at a dose of 80 mg/m²/day. The endpoint was the pathological complete response (pCR) rate.

Results

Twenty-eight patients were finally enrolled. The following patient characteristics were recorded: clinical Stage (II: n = 12, III: n = 16), median age (66 years, range 40-77 years), male/female ratio (20/8), and lesion site (Ra-Rb:3/Rb:23/Rb-P:2). Preoperative treatment was completed in 27 patients (96%). Treatment abandonment occurred because of diarrhea. Grade 3 or higher adverse events were observed in one (4%) patient with two events. No serious adverse events occurred in the ≥ 70 years group. The response rate was 68% in all patients and 68% among elderly patients. Radical resection was achieved in all patients, including 19 (68%) who underwent sphincter-preserving surgery. The pCR rate was 11% (three patients). The five-year disease-free survival rate was 68%, and the overall survival rate was 82%. Local recurrence occurred in only one patient five years after surgery.

Conclusion

Preoperative CRT with S-1 alone may be a safe and acceptable regimen from the perspective of adverse events and oncological outcomes.

Trial registration

UMIN Clinical Trial Registry: UMIN000013598. Registered 1 April 2014, https://upload.umin.ac.jp/cgi-open-bin/ctr_e/ctr_view.cgi?recpt-no=R000015887.

Predictive Value of the Prognostic Nutritional Index in Neoadjuvant Chemoradiotherapy for Rectal Cancer

BACKGROUND/AIM

Prognostic nutritional index (PNI) and neutrophil-to-lymphocyte ratio (NLR) indicate nutritional status and host immunity. We used immunohistochemistry and apparent diffusion coefficient (ADC) values calculated using diffusion-weighted imaging (DWI) to investigate relationships of these factors with pathological and radiological characteristics in rectal cancer treated with neoadjuvant chemoradiotherapy (nCRT).

PATIENTS AND METHODS

We evaluated expression levels of VEGFA, CD8, CD33, and ADC values in tumors pre/post nCRT; and analyzed the relationships between those factors and PNI, NLR in 32 patients.

RESULTS

Pretreatment PNI negatively correlated with change in tumor stromal CD8 ⁺ T cells and positively correlated with ADC values. Pretreatment NLR and PNI change correlated with recurrence-free survival (RFS).

CONCLUSION

Patients with higher pretreatment PNI had greater changes in ADC values and stromal CD8 ⁺ T-cell counts, and those with greater PNI reduction from nCRT had a worse prognosis. Proper nutritional management during nCRT benefits patients and may lead to better prognosis in rectal cancer.

Predictive clinical model of tumor response after chemoradiation in rectal cancer

Survival improvement in rectal cancer treated with neoadjuvant chemoradiotherapy (nCRT) is achieved only if pathological response occurs. Mandard tumor regression grade (TRG) proved to be a valid system to measure nCRT response. The ability to predict tumor response before treatment may significantly have impact the selection of patients for nCRT in rectal cancer. The aim is to identify potential predictive pretreatment factors for Mandard response and build a clinical predictive model design. 167 patients with locally advanced rectal cancer were treated with nCRT and curative surgery. Blood cell counts in peripheral blood were analyzed. Pretreatment biopsies expression of cyclin D1, epidermal growth factor receptor (EGFR), vascular endothelial growth factor (VEGF) and protein 21 were assessed. A total of 61 single nucleotide polymorphisms were characterized using the Sequenom platform through multiplex amplification followed by mass-spectometric product separation. Surgical specimens were classified according to Mandard TRG. The patients were divided as: "good responders" (Mandard TRG1-2) and "poor responders" (Mandard TGR3-5). We examined predictive factors for Mandard response and performed statistical analysis. In univariate analysis, distance from anal verge, neutrophil lymphocyte ratio (NLR), cyclin D1, VEGF, EGFR, protein 21 and rs1810871 interleukin 10 (IL10) gene polymorphism are the pretreatment variables with predictive value for Mandard response. In multivariable analysis, NLR, cyclin D1, protein 21 and rs1800871 in IL10 gene maintain predictive value, allowing a clinical model design.

CONCLUSION

It seems possible to use pretreatment expression of blood and tissue biomarkers, and build a model of tumor response prediction to neoadjuvant chemoradiation in rectal cancer.

Abdominoperineal excision following preoperative radiotherapy for rectal cancer: unfavorable prognosis even with negative circumferential resection margin

AIM

To evaluate whether an abdominoperineal excision (APE) is associated with increased local recurrence (LR) and shortened disease-free survival (DFS) in mid-low rectal cancer with a negative circumferential resection margin (CRM).

METHODS

283 consecutive cases of mid-low rectal cancer underwent preoperative 30 Gy/10 F radiotherapy and surgery in Peking University Cancer Hospital between August 2003 and August 2009. Patients with positive CRM and intraoperative distant metastasis were precluded according to exclusion criteria. Survival analyses were performed in patients with APE or non-APE procedures.

RESULTS

256 of the 283 (90.5%) cases were enrolled in the analysis, including 78 (30.5%) and 178 (69.5%) cases who received APE and non-APE procedures. Fewer female patients (P = 0.016), lower level of tumor (P = 0.000) and higher body mass index (P = 0.006) were found in the APE group. On univariate analysis, the APE group had a higher LR rate (5.1% vs 1.1%, P = 0.036) and decreased DFS (73.1% vs 83.4%, P = 0.021). On multivariate analysis, APE procedure was also an independent risk factor for LR (HR = 5.960, 1.085-32.728, P = 0.040) and decreased DFS (HR = 2.304, 1.298-4.092, P = 0.004). In stratified analysis for lower rectal cancer, APE procedure was still an independent risk factor for higher LR rate (5.6% vs 0%, P = 0.024) and shortened DFS (91.5% vs 73.6%, P = 0.002).

CONCLUSION

Following preoperative 30 Gy/10 F radiotherapy, APE procedure was still a predictor for LR and decreased DFS even with negative CRM. More intensive preoperative treatment should be planned for the candidates who are scheduled to receive APE with optimal imaging assessment.

Post-chemoradiation anastomotic recurrence in locally advanced rectal cancer: no increased risk associated with distal margin

BACKGROUND AND PURPOSE

Anastomotic recurrence after radical sphincter-preserving surgery preceded by neoadjuvant therapy in locally advanced rectal cancer is an uncommon event that merits further assessment. The aim of this study is to analyze the effect of preoperative chemoradiation on the risk of anastomotic recurrence. Based on the initial extension of the tumor, we analyzed whether the distal surgical section was calculated through the virtual initial extension of the rectal tumor.

PATIENTS AND METHODS

Eligible patients with locally advanced rectal cancer were offered preoperative chemoradiation, sphincter sparing surgery and intraoperative radiation therapy boost.

RESULTS

180 patients were treated with anterior resection (40 %), low anterior resection (45.6 %) and ultra-low anterior resection (14.4 %). With a median follow-up of 41.1 months (0.36-143 months), anastomotic recurrence was diagnosed in 9 patients (5 %). There was no statistical correlation with downstaging (T or N), downsizing effects, or with distance from the lower limit of the residual lesion to the distal margin. Virtual intratumoral surgical section was speculated in 44 patients (3 developed anastomotic recurrence; 6.8 vs 4.8 %, p = 0.482).

CONCLUSION

Anastomotic recurrence in patients with rectal cancer treated with neoadjuvant chemoradiation is an infrequent event. Virtual intratumoral surgical sections followed by anastomosis do not contribute to an excessive risk of recurrence. Our findings encourage the development of policies for preservation of the ano-rectal complex in rectal cancer patients.

Improvement in T-staging of rectal carcinoma: using a novel endorectal ultrasonography technique with sterile coupling gel filling the rectum

Our purpose was to study the accuracy of using endorectal ultrasonography (ERUS) with sterile coupling gels filling the rectum in the preoperative T-staging of rectal carcinoma. A total of 189 patients with confirmed rectal carcinoma were recruited. All underwent ERUS and surgery within the week following sonography. EURS was performed by introducing sterile coupling gel into the rectum. Two radiologists looked at the images at the same time and agreed upon staging. Rectal carcinoma was staged from Tis to T4. The accuracy of T-staging by ERUS was 89.95%. The sensitivity, specificity, PPV and NPV for ERUS at different stages were calculated. For early stage (Tis and T1), these values were 93.62%, 97.89%, 93.62% and 97.89%, respectively. ERUS filling with sterile coupling gel in the rectum overcomes the pressure effect from a water bath and the restriction caused by tumor stenosis, thus, greatly improving the accuracy of T-staging. The examination is real-time, safe and inexpensive.

Endorectal ultrasound: its role in the diagnosis and treatment of rectal cancer

With development over the past 25 years of new surgical techniques and neoadjuvant therapy regimens for rectal cancer, physicians now have a range of treatment options that minimize morbidity and maximize the potential for cure. Accurate pretreatment staging is critical, ensuring adequate therapy and preventing overtreatment. Many options exist for staging primary rectal cancer. However, endorectal ultrasound (ERUS) remains the most attractive modality. It is an extension of the physical examination, and can be performed easily in the office. It is cost effective and is generally well tolerated by the patient, without need for general anesthesia. The authors discuss the data currently available on ERUS, including its accuracy and limitations, as well as the technical aspects of performing ERUS and interpreting the results. They also discuss new ultrasound technologies, which may improve rectal cancer staging in the future.

Endosonographic staging of lower intestinal malignancy

The use of EUS in the assessment of rectal pathology is well established. The accurate staging of lower intestinal tumours predicts prognosis and guides the planning of individual patient treatment. Increased experience and the development of high resolution three-dimensional EUS has lead to the greater accuracy of rectal staging with EUS of rectal tumours now considered the gold standard showing T stage accuracy that ranges from 75% to 95%, with N stage accuracy ranging from 65% to 80%. The use of EUS in the staging of colonic pathology, however, is not so well established though advances in miniprobe EUS has improved the assessment of colonic tumours. EUS is also of benefit in the assessment of anal pathology though here, accurate correlation with histology has not been firmly established.

Magnetic resonance imaging in locoregional staging of rectal adenocarcinoma

A comprehensive overview of the current status of magnetic resonance imaging (MRI) in the locoregional assessment and management of rectal adenocarcinoma is presented. Staging systems for rectal cancer and treatment strategies in its management are discussed to give the reader the context that shapes MRI acquisition techniques and interpretation. Findings on MRI are detailed and their accuracy reviewed based on currently available evidence. Optimization of MRI acquisition and relevant pelvic anatomy are reviewed. A detailed description of our approach in interpreting MRI for locoregional staging of rectal cancer is given and future directions are also introduced.

Rigid sigmoidoscopy and MRI are not interchangeable in determining the position of rectal cancers

PURPOSE

1) To analyse for interchangeability of rigid sigmoidoscopy and MRI in determining the distance from anus to tumour, and to determine if anterior/posterior location influences this difference. 2) To analyse the effect of preoperative chemo-radiotherapy on the distance from anus to tumour.

METHODS

Retrospective investigation of endoscopy reports and MRI series of 144 consecutive patients operated for rectal cancer.

RESULTS

The mean distance from the anal verge to the tumour measured by sigmoidoscopy was 82mm and by MRI 61mm (p<0.01). For tumours in the anterior quadrant this difference was 30mm and for tumours located in the posterior quadrant only 12mm. The distributions of the cancers as low, middle and high differ by more than 10% between the two methods. The coefficient of correlation between measurements was 0.9 but the variation was not acceptable. The length of the tumours decreased by 16mm after neoadjuvant treatment, but the distance from tumour to anus increased by only 4mm.

CONCLUSION

1) MRI and sigmoidoscopy are not interchangeable in determining the distance from anus to tumour simply by correcting for the length of the anal canal. It has not been determined if measurements from MRI or sigmoidoscopy are more accurate, but current evidence concerning the effect of neoadjuvant irradiation at different positions in the rectum is based upon rigid sigmoidoscopy. 2) The gain in tumour free distance above the anus induced by neoadjuvant treatment is small. Facilitation of sphincter-saving surgery should not be an argument for neoadjuvant treatment.

Oncologic outcomes after radical surgery following preoperative chemoradiotherapy for locally advanced lower rectal cancer: abdominoperineal resection versus sphincter-preserving procedure

BACKGROUND

Over the past several years, preoperative chemoradiotherapy (CRT) has contributed remarkably to make more sphincter-preserving procedure (SPP) possible for lower rectal cancer. The aim of this study was to compare the outcomes between abdominoperineal resection (APR) and SPP after preoperative CRT in patients with locally advanced lower rectal cancer.

METHODS

A retrospective investigation was conducted with a total of 122 patients who underwent radical surgery combined with preoperative CRT for locally advanced lower rectal cancer. Of these, 50 patients underwent APR and 72 received SPP. Surgery was performed 6-8 weeks after completion of preoperative CRT. Oncologic outcomes were compared between the two groups, and the clinicopathologic factors affecting the treatment outcomes were evaluated.

RESULTS

Circumferential resection margin (CRM) involvement (P = 0.037) and postoperative complication rate (P = 0.032) were significantly different between APR and SPP. Patients who underwent APR had a higher 5-year local recurrence (22.0% vs. 11.5%, P = 0.028) and lower 5-year cancer-specific survival (52.9% vs. 71.1%, P = 0.03) rate than those who underwent SPP. Pathologic N stage was the most critical predictor for local recurrence and survival.

CONCLUSIONS

Our study shows that APR following preoperative CRT exhibited more adverse oncologic outcomes compared with SPP. This result may be due to higher rates of CRM involvement in APR even with preoperative CRT. We suggest that sharp perineal dissection and wider cylindrical excision at the level of the anorectal junction are required to avoid CRM involvement and improve oncologic outcomes in patients who undergo APR following preoperative CRT.