Can Rectal Cancers With Pathologic T0 After Neoadjuvant Chemoradiation (ypT0) Be Treated by Transanal Excision Alone?

Evaluation of transrectal ultrasound-guided tru-cut biopsy as a complementary method for predicting pathological complete response in rectal cancer after neoadjuvant treatment: a phase II prospective and diagnostic trial

IMPORTANCE

Patients with pathological complete response (pCR) of rectal cancer following neoadjuvant treatment had better oncological outcomes. However, reliable methods for accurately predicting pCR remain limited.

OBJECTIVE

To evaluate whether transrectal ultrasound-guided tru-cut biopsy (TRUS-TCB) adds diagnostic value to conventional modalities for predicting pathological complete response in patients with rectal cancer after neoadjuvant treatment.

DESIGN, SETTING, AND PARTICIPANTS

This study evaluated data of patients with rectal cancer who were treated with neoadjuvant treatment and reassessed using TRUS-TCB and conventional modalities before surgery. This study is registered with ClinicalTrials.gov.

MAIN OUTCOMES AND MEASURES

The primary outcome was accuracy, along with secondary outcomes including sensitivity, specificity, negative predictive value, and positive predictive value in predicting tumour residues. Final surgical pathology was used as reference standard.

RESULTS

Between June 2021 and June 2022, a total of 74 patients were enroled, with 63 patients ultimately evaluated. Among them, 17 patients (28%) exhibited a complete pathological response. TRUS-TCB demonstrated an accuracy of 0.71 (95% CI, 0.58-0.82) in predicting tumour residues. The combined use of TRUS-TCB and conventional modalities significantly improved diagnostic accuracy compared to conventional modalities alone (0.75 vs. 0.59, P =0.02). Furthermore, TRUS-TCB correctly reclassified 52% of patients erroneously classified as having a complete clinical response by conventional methods. The occurrence of only one mild adverse event was observed.

CONCLUSIONS AND RELEVANCE

TRUS-TCB proves to be a safe and accessible tool for reevaluation with minimal complications. The incorporation of TRUS-TCB alongside conventional methods leads to enhanced diagnostic performance.

Current status of surgical treatment of rectal cancer in China

With the changing lifestyle and the acceleration of aging in the Chinese population, the incidence and mortality of colorectal cancer (CRC) have risen in the last decades. On the contrary, the incidence and mortality of CRC have continued to decline in the USA since the 1980s, which is mainly attributed to early screening and standardized diagnosis and treatment. Rectal cancer accounts for the largest proportion of CRC in China, and its treatment regimens are complex. At present, surgical treatment is still the most important treatment for rectal cancer. Since the first Chinese guideline for diagnosis and treatment of CRC was issued in 2010, the fourth version has been revised in 2020. These guidelines have greatly promoted the standardization and internationalization of CRC diagnosis and treatment in China. And with the development of comprehensive treatment methods such as neoadjuvant chemoradiotherapy, targeted therapy, and immunotherapy, the post-operative quality of life and prognosis of patients with rectal cancer have improved. We believe that the inflection point of the rising incidence and mortality of rectal cancer will appear in the near future in China. This article reviewed the current status and research progress on surgical therapy of rectal cancer in China.

Short-Term Clinical and Oncological Outcome of Prolonging Operation Interval After Neoadjuvant Chemoradiotherapy for Locally Advanced Middle and Low Rectal Cancer

Purpose

The purpose of this study is to evaluate the short-term clinical and oncological outcome of prolonging operation interval to 11 weeks after the end of radiotherapy for locally advanced middle and low rectal cancer.

Methods

A total of 123 patients with stage II/III (cT3/T4 or N+) low and middle rectal cancer who had undergone operation after neoadjuvant chemoradiotherapy were selected. According to the interval time between the last radiotherapy and operation, they were assigned to a short-interval group (SG, <11 weeks, n=66) and long-interval group (LG, ≥11 weeks, n=57). The relations among interval time and short-term clinical outcome and oncological outcome were analyzed.

Results

The analysis found that basic information, clinical characteristics, and preoperative treatment between the two groups had no significant difference. There were no differences in operation time, estimated intraoperative blood loss and postoperative complications. The rate of sphincter preservation in the low and middle rectum was 66.7% in the short-interval group and 59.7% in the long-interval group (P=0.42). The incidence of anastomotic leak in the long-interval group was higher than that in the short-interval group (P=0.08). There was no significant difference in the recovery time of intestinal function and median duration of hospitalization between the two groups. The pathological complete remission rate was 17.07%. Multivariate analysis showed interval time had no influence on pathological complete remission. There was no significant difference in 3-year overall survival and 3-year disease-free survival between the two groups. The risk of recurrence and metastasis in patients with positive lymph nodes was higher than those with negative lymph nodes (P<0.05), HR=4.812 (95% CI 2.4–9.648).

Conclusion

Prolonging the interval time of operation to 11 weeks after neoadjuvant chemoradiotherapy for middle and low rectal cancer does not improve the pathologic complete remission, morbidity, and mortality. There was no significant effect on oncologic outcome after prolonging the operation interval. Therefore, it is safe to prolong the interval of operation to 11 weeks.

How to measure tumour response in rectal cancer? An explanation of discrepancies and suggestions for improvement

Various methods categorize tumour response after neoadjuvant therapy, including down-staging and tumour regression grading. Response categories allow comparison of different treatments within clinical trials and predict outcome. A reproducible response categorization could identify subgroups with high or low risk for the most appropriate subsequent treatments, like watch and wait. Lack of standardization and interpretation difficulties currently limit the usability of these approaches. In this review we describe these difficulties for the evaluation of chemoradiation in rectal cancer. An alternative approach of tumour response is based on patterns of residual disease, including fragmentation. We summarise the evidence behind this alternative method of response categorisation, which explains a number of very relevant clinical discrepancies. These issues include differences between downstaging and tumour regression, high local regrowth in advanced tumours during watchful waiting procedures, the importance of resection margins, the limited value of post-treatment biopsies and the relatively poor outcome of patients with a near complete pathological response. Recognition of these patterns of response can allow meaningful development of novel biomarkers in the future.

Endoscopy and magnetic resonance imaging-based prediction of ypT stage in patients with rectal cancer who received chemoradiotherapy: Results from a prospective study of 110 patients

Accurate tumor response determination remains inconclusive after preoperative chemoradiation therapy (CRT) for rectal cancer. This study aimed to investigate whether clinical assessment, such as endoscopy and magnetic resonance imaging (MRI), can accurately predict ypT stage and select candidates for pelvic organ-preserving surgery in rectal cancer after preoperative CRT. A total of 110 patients who underwent preoperative CRT followed by curative resection for rectal cancer were prospectively enrolled. Magnetic resonance tumor regression grade (mrTRG) using T2-MRI, endoscopic evaluation, and combination modality (combination of endoscopy and mrTRG) were used to analyze tumor response after preoperative CRT. Endoscopic findings were categorized as 3 grades and the mrTRG was assessed into 5 grades. Twenty-nine patients (26.4%) had achieved pathologic complete response. When predicting ypT0, endoscopy showed significantly higher area under the curve (AUC 0.818) than did mrTRG (AUC 0.568) and combination modality (AUC 0.768) in differentiating good response from poor response (P < .001). Both endoscopy and combination modality showed significantly higher diagnostic performance in sensitivity (79.31%), positive predictive value (PPV 67.65%), negative predictive value (NPV 92.11%), and accuracy (84.55%) than those of MR tumor response (sensitivity 37.93%, PPV 36.67%, NPV 77.50%, and accuracy 66.36%) for the prediction of ypT0 (P < .001). Combination modality showed significantly higher diagnostic performance in sensitivity (56.92%), NPV (56.92%), and accuracy (67.27%) compared with those of mrTRG. Neither endoscopy, nor mrTRG, nor the combination modality had adequate diagnostic performances to be clinically acceptable in selecting candidates for nonoperative treatment strategies. However, endoscopy may be incorporated in clinical restaging strategy in planning the extent of surgical resection in patients with rectal cancer.

Robotic transanal minimally invasive surgery for rectal cancer after clinical complete response to neoadjuvant chemoradiation

BACKGROUND

Full-thickness local excision (FTLE) for rectal cancer showing clinical complete remission (cCR) after neoadjuvant chemoradiation therapy (NCRT) is associated with good oncological results. The purpose of this study was to report the results of robotic transanal minimally invasive surgery for such patients.

METHODS

Patients were treated with a 5-fluorouracil-based NCRT regimen. The determination of cCR was based on digital rectal examination, colonoscopy, and magnetic resonance imaging.

RESULTS

Six patients underwent transanal FTLE using the da Vinci Xi surgical system. The median operative time was 106.5 minutes, and the estimated blood loss was minimal. The mean length of hospital stay was 4.2 days. After 18.2 months of follow-up, none of the patients developed local recurrences or distant disease.

CONCLUSIONS

With the use of robotic technology, FTLE can be performed with relative ease and can be considered as a viable alternative to radical resection or a "Watch and Wait" strategy.

Laparoscopic Total Mesorectal Excision Following Transanal Endoscopic Microsurgery for Rectal Cancer

BACKGROUND

Patients' selection for transanal endoscopic microsurgery (TEM) depends on diagnostic modalities; however, there are still some limitations in the preoperative diagnosis of rectal lesions, and in some reports, up to third of the adenomas resected by TEM were found to be adenocarcinoma; therefore, salvage radical resection (RR) remains necessary for achieving oncological resection. Salvage RR may encounter some technical problems as the violation of the mesorectum and the scar formation. In this study, we aimed to report the outcome in patients undergoing salvage RR in terms of morbidity and oncological results.

MATERIALS AND METHODS

Demographic and clinical data pertaining to patients undergoing RR following TEM between 2004 and 2014 were retrospectively collected.

RESULTS

One hundred forty one TEM were performed in the study period, 53 (38%) for malignant rectal lesions. Indication for TEM: 15 (28%) benign adenoma, 25 (47%) early rectal cancer, and 13 (25%) had clinical complete response after neoadjuvant radiochemotherapy. Ten (19%) patients had no residual tumor in TEM specimen, 15 (28%) had T1, and 2 of them underwent salvage low anterior resection (LAR). Ten (19%) had T2, 4 had LAR, and 1 had abdominoperineal resection (APR). Five (9%) had a T3, 3 underwent LAR, and 2 had APR. Among the 13 (25%) after chemo-radiotherapy (CRT), 4 had salvage AR. The time from TEM to RR was 47 days (range32-70). Of 16 salvage surgeries, 8 (50%) were laparoscopic. The median operative time was 210 minutes (range165-360). Five patients had protective ileostomy. Rectal perforation occurred in 2 (12%) patients; both had a posterior location, one after CRT. Two (12%) postoperative small-bowl obstruction and three wound infections occurred. There was no perioperative mortality in any of the patients who underwent RR. The final pathology was no residual disease in 9, T3N1 in 1, T3N0 in 3, T2N1 in 1, and T2N0 in 2 patients. Eight (50%) had adjuvant chemotherapy.

CONCLUSION

Laparoscopic total mesorectal excision following TEM seems to be safe, and with no negative impact of the completeness of the resection. The concern of intraoperative specimen perforation is real, and should be dealt with meticulous technique and careful dissection, particularly after CRT.

Incidence of Metachronous Distant Metastasis and ypN Classification Influence Patient Survival in Endosonographically Confirmed uT3 Rectal Cancer after Neoadjuvant Therapy and R0 Resection: A Historical Cohort Analysis

BACKGROUND

Tumor response after neoadjuvant radiochemotherapy (NRC) prior to surgery and other parameters are likely to have an influence on the survival rate of patients suffering from T3 rectal cancer.

METHODS

51 patients (17 female, 34 male; 59.0 years; Apache < 9 points: 95.1%; ASA I-II 88.3% and ASA III 11.8%) were treated with NRC (50.4 Gy; 5-fluorouracil/folinic acid) 4-6 weeks prior to surgery because of uT3 rectal cancer (G2: 96%; adenocarcinoma 86.3%; cUICC II 62.7%). NRC led to a tumor response (TR) (ypT0-ypT2) in 45.1% (ypT0N0M0 7.8%).

RESULTS

Neither the age of patients nor Apache/ASA score, histology, UICC staging, ypTNM, Dukes staging, infiltration of vessels, surgical procedure, local recurrence nor TR had a significant influence on the patients' survival time. Patients with metachronous distant metastasis (MDM) during the follow-up period (mean: 8.2 years; 1 month to 14.5 years) and patients with ypN1-ypN2 had a significantly shorter survival time.

CONCLUSIONS

NRC prior to surgery leads to a remarkable TR rate but has no significant impact of TR on the patients' survival time. Occurrence of MDM during the follow-up period and ypN1/N2 status do have a greater influence. It is necessary to investigate larger cohorts of patients in the future to obtain more conclusive results and to define factors with influence on survival.

Influence of Preoperative Chemoradiotherapy on the Surgical Strategy According to the Clinical T Stage of Patients With Rectal Cancer

The aim of this study was to evaluate the pathologic responses and changes to surgical strategies following preoperative chemoradiotherapy (PCRT) in rectal cancer patients according to their clinical T stage (cT).The use of PCRT has recently been extended to less advanced disease.The authors enrolled 650 patients with cT2 to 4 mid and low rectal cancer who received both PCRT and surgical resection. The rate of total regression and the proportion of local excision were compared according to the cT category. The 3-year recurrence-free survival (RFS) rate was compared using the log-rank test according to patient cT category, pathologic stage, and type of surgical treatment.Patients with cT2 were older (P = 0.001), predominately female (P = 0.028), and had low-lying rectal cancer (P = 0.008). Pathologic total regression was achieved most frequently in cT2 patients (54% of cT2 versus 17.6% of cT3 versus 8.2% of cT4; P < 0.001). Local excision was performed on 42 cT2 (42%) and 24 cT3 (5.2%) patients (P < 0.001). The 3-year RFS rates differed according to both cT (P < 0.001) and ypT stage (P < 0.001). Among patients with ypT0 to 1 disease, the 3-year RFS did not differ according to the type of surgical treatment received (P = 0.5).Total regression of the primary tumor and a change in the surgical strategy after PCRT are most commonly seen in cT2 disease. Although PCRT is not generally indicated for cT2 rectal cancer, optimal surgical treatment may be achieved with the tailored use of PCRT.

Transanal Endoscopic Microsurgery

Transanal endoscopic microsurgery (TEM) was developed by Professor Gerhard Buess 30 years ago at the dawn of minimally invasive surgery. TEM utilizes a closed proctoscopic system whereby endoluminal surgery is accomplished with high-definition magnification, constant CO2 insufflation, and long-shafted instruments. The end result is a more precise excision and closure compared to conventional instrumentation. Virtually any benign lesion can be addressed with this technology; however, proper patient selection is paramount when using it for cancer.

Transanal Endoscopic Microsurgery After Neoadjuvant Chemoradiotherapy for Rectal Cancer

BACKGROUND

Radical rectal resection following neoadjuvant chemoradiation therapy (CRT) for locally advanced rectal cancer is accompanied by relatively high morbidity. Local excision of rectal cancer may be more appropriate for some frail patients with severe comorbidities. Transanal endoscopic microsurgery (TEM), consisting of local excision of selected rectal cancers, has been associated with low rates of postoperative complications. Because neoadjuvant CRT for rectal cancer may be associated with increased complications, the suitability of TEM following CRT is still unclear. In this study we aimed to assess the clinical outcomes of patients undergoing TEM following neoadjuvant CRT.

PATIENTS AND METHODS

This study retrospectively analyzed all patients undergoing TEM for malignant rectal tumor in our institution between 2004 and 2010. They were divided into those who received CRT (CRT group) and those without CRT (non-CRT group). Demographics and clinical data were compared.

RESULTS

Forty-four of 97 patients who underwent TEM were included: 13 CRT and 31 non-CRT. Age, comorbidities, and the duration of the procedure were similar for both groups. There were no significant group differences in tumor diameter (2.1 cm [range, 0.5-3.5 cm] and 2.9 cm [range, 0.5-4.2 cm], respectively; P=.125) or distance of the lower part of the tumor from the anal verge (6.7 cm [range, 5-10 cm] and 7.7 cm [range, 5-15 cm], respectively; P=.285). Two non-CRT patients had peritoneal entry, and 1 of them underwent protective ileostomy because of insecure rectal defect closure. One non-CRT patient underwent a re-operation for postoperative bleeding. The other perioperative complications were minor and included urinary retention requiring catheter placement (2 patients in each group), pulmonary edema (1 non-CRT patient), and pneumonia (1 non-CRT patient). All complications were managed conservatively. There was no wound disruption, major complication, or mortality in either group.

CONCLUSIONS

With proper patient selection, TEM can be performed safely following CRT, without major complication or increased postoperative morbidity.

Regional lymph node status after neoadjuvant chemoradiation of rectal cancer producing a complete or near complete rectal wall response

AIM

Transanal excision of the tumour site after complete response to chemoradiotherapy can determine the rectal wall response to treatment. This study was designed to assess whether the absence of tumour in the rectal wall corresponds to the absence of tumour in the mesorectum (true pathological complete response).

METHOD

A retrospective review identified patients who underwent preoperative chemoradiation therapy for advanced mid and low rectal cancer followed by routine pre-planned radical surgery with total mesorectal excision. Patients in whom the pathology specimen showed no residual tumour in the rectal wall (ypT0) or a ypT1 lesion were assessed for tumour involvement in the mesorectum.

RESULTS

Seventy-eight patients who underwent pelvic chemoradiation followed by radical surgery were reviewed. The rectal wall tumour disappeared in eight (ypT0). Of these, residual tumour was found in the mesorectum (ypT0N1) in one (12%) patient. Eleven patients were found to have ypT1 residual tumour. Of these, two (18%) had a final post-surgical staging of ypT1N1.

CONCLUSION

Complete rectal wall tumour eradication was achieved in 10% of the patients, and downstaging to ypT1 was achieved in 14%. In 15% (12% in ypT0 and 18% in ypT1) of these patients, residual tumour cells were evident in the mesorectum. This would probably have rendered these patients with residual disease had a nonradical approach of transanal excision of the original tumour site been employed. Caution should be taken when considering the avoidance of radical surgery.

Five-year outcomes of preoperative chemoradiation for rectal carcinoma in Saudi population: single-institutional experience

OBJECTIVES

Preoperative chemoradiation (CRT) followed by surgery is the standard treatment for locally advanced rectal cancer (LARC). The outcomes of preoperative CRT in Saudi patients with LARC have not been widely studied. The study reports long-term outcomes after preoperative CRT followed by curative surgery in Saudi patients with LARC.

DESIGN AND SETTINGS

A retrospective, single-institutional study performed in the tertiary care oncology center in Saudi Arabia.

MATERIALS AND METHODS

A total of 154 out of 204 patients with LARC were treated with preoperative CRT and followed by surgery at the oncology center between September 2005 and November 2012. Data regarding the response rates, toxicity profile, locoregional control (LRC), distant metastasis control (DMC), overall survival (OS), and disease-free survival (DFS) rates were analyzed.

RESULTS

The median age of the study population was 56.6 years (range: 26-89). Predominant clinical stages were IIA (70 patients; 45.4%) and IIIB (49 patients; 31.8%). Majority of patients (79.8%) underwent a complete total mesorectal excision (TME). Complete pathological response (ypT0N0) was seen in 26 patients (16.8%). At 5 years, locoregional recurrence (LR) was reported in 12 patients (7.8%), and distant metastases were noted in 33 patients (21.4%). The 5-year cumulative LRC, DMC, OS, and DFS rates were 91%, 71.3%, 78%, and 64.8%, respectively. Stage, nodal status, circumferential margins, ypT0N0, and adjuvant chemotherapy were found to be important prognostic factors for DFS.

CONCLUSION

The results of preoperative CRT followed by surgery and adjuvant chemotherapy in Saudi population are comparable with international data.

Can We Predict Complete or Major Response after Chemoradiotherapy for Rectal Cancer by Noninvasive Methods? Results of a Prospective Study on 61 Patients

Rectal preservation has been proposed as an alternative to radical resection in patients with presumed complete or major response to chemoradiotherapy (CRT). The aim of this prospective study was to evaluate the accuracy of digital rectal examination (DRE) and magnetic resonance imaging (MRI) to predict major or complete rectal cancer response to CRT. Over 2 years, 61 patients underwent radical resection after CRT for rectal cancer. DRE and MRI were carried out before and 6 to 8 weeks after the end of CRT. Data from DRE and MRI post-CRT were compared with pathological examinations. At pathological examination, major/complete responses were recorded for tumors classified ypT1N0 and ypT0N0, respectively. DRE post-CRT showed major/complete response in 26 cases, of which 14 (54%) were confirmed by pathology. The positive (PPV) and negative (NPV) predictive values of DRE to predict major/complete response were 54 and 88 per cent, respectively. MRI post-CRT showed major/complete response in 12 cases, of which nine (75%) were confirmed by pathology. The PPV and NPV of MRI to predict major/complete response were 75 and 82 per cent, respectively. Data from DRE and RMI post-CRT were concordant in 45 patients. The PPV and NPV of concordant DRE and MRI to predict major/complete response were 82 and 91 per cent, respectively. DRE and MRI do not appear to be sufficiently accurate for safe selection of patients appropriate for a rectum-sparing strategy because the risk of leaving an invasive tumor untreated is 18 per cent.

Risk factors for local recurrence following neoadjuvant chemoradiotherapy for rectal cancers

Local recurrence (LR) has an adverse impact on rectal cancer treatment. Neoadjuvant chemoradiotherapy (nCRT) is increasingly administered to patients with progressive cancers to improve the prognosis. However, LR still remains a problem and its pattern can alter. Correspondingly, new risk factors have emerged in the context of nCRT in addition to the traditional risk factors in patients receiving non-neoadjuvant therapies. These risk factors are decisive when reviewing treatment options. This review aims to elucidate the distinctive risk factors related to LR of rectal cancers in patients receiving nCRT and to clarify their clinical significance. A search was conducted on PubMed to identify original studies investigating patients with rectal cancer receiving nCRT. Outcomes of interest, especially potential risk factors for LR in patients with nCRT, were then analyzed. The clinical importance of these risk factors is discussed. Remnant cancer cells, lymph-nodes and tumor response were found to be major risk factors. Remnant cancer cells decide the status of resection margins. Local excision following nCRT is promising in ypT0-1N0M0 cases. Dissection of lateral lymph nodes should be considered in advanced low-lying cancers. Although better tumor response resulted in a relatively lower recurrence rate, the evidence available is insufficient to justify a non-operative approach in clinical complete responders to nCRT. LR cannot be totally avoided by current multidisciplinary approaches. The related risk factors resulting from nCRT should be considered when making decisions regarding treatment selection.

Long-term outcome of local excision after complete pathological response to neoadjuvant chemoradiation therapy for rectal cancer

BACKGROUND

Neoadjuvant chemoradiotion therapy (CRT) for advanced rectal cancer has improved local disease. Complete rectal wall tumor regression may be associated with the absence of viable cancer cells in the mesorectum, and thus local excision (LE) of such lesions as an alternative to radical surgery has recently gained interest. We report the long-term outcome of LE in patients with a mural pathological complete response (ypT0) after CRT.

METHODS

A retrospective review of patients with rectal cancer treated by CRT and followed by LE with pathological complete response in the specimen between 1998 and 2009 was performed.

RESULTS

A total of 174 patients had neoadjuvant CRT, and 68 (39 %) showed complete clinical response (cCR). Thirty-one of the cCR patients underwent LE; 23 of them resulted in ypT0 and 8 had residual disease. The ypT0 group included 12 men and 11 women with a median age of 66. The pretreatment stage was T3N1 in 4 (17 %) patients, T3N0 in 11 (48 %), T2N1 in 3 (13 %), and T2N0 in 5 (22 %). The median tumor distance from the anal verge was 6 cm. Sixteen patients (70 %) underwent transanal excision, and 7 (30 %) were treated by transanal-endoscopic microsurgery. Three patients died: one of pneumonia, one of melanoma of the rectum, and one of lung carcinoma. No local or distant recurrences were detected in the remaining 20 patients. The median follow-up was 87 months.

CONCLUSIONS

Although radical rectal resection is the treatment of choice, LE of complete rectal tumor regression could be a safe alternative with an acceptable result in selected patients.

A prospective analysis of patient outcome following treatment of T3 rectal cancer with neo-adjuvant chemoradiotherapy and transanal excision

BACKGROUND

Local excision is an alternative to anterior or abdomino-perineal resection in patients with early rectal cancer. In more advanced disease, neo-adjuvant therapy (CRXT) can result in significant disease regression such that local excision may be considered. The primary aim was to assess oncological outcome in patients with T3 rectal cancer treated with CRXT and local excision due to unsuitability for or aversion to anterior resection and stoma. The secondary aim was to examine oncological outcomes in patients treated in a similar way in the published literature.

METHODS

Between July 2006 and July 2009, patients with rectal cancer staged T3, N0/N1, M0 who were deemed unfit for or who refused anterior resection were offered long-course CRXT. Patients were restaged 8 weeks following completion. If there was a good response (regression grade 2 or 3 clinically and radiologically), full thickness transanal excision was performed. All patients were followed regularly (monthly CT abdomen/pelvis and annual endoscopy) to assess for recurrence of disease. A literature search of PubMed was performed to identify all prospective data available of T3 rectal cancers managed with CRXT and local excision.

RESULTS

Ten patients were treated over 3 years. Six patients had complete pathological response, while four patients had a partial response. The resection margins following local excision were clear in all. There was no local recurrence (median follow-up 24 months, range 9-42 months).

CONCLUSION

Neo-adjuvant chemoradiotherapy and local excision is an option in patients unfit for or averse to major surgical resection if there is a good response to CRXT.

MRI features of the complete histopathological response of locally advanced rectal cancer to neoadjuvant chemoradiotherapy

AIM

To describe the post-chemoradiotherapy magnetic resonance imaging (MRI) features of locally advanced rectal carcinoma (LARC) in which there has been a complete histopathological response to neoadjuvant chemoradiotherapy (CRT).

MATERIALS AND METHODS

This retrospective cohort study was performed between January 2005 and November 2009 at a regional cancer centre. Consecutive patients with LARC and a histopathological complete response to long-course CRT were identified. Pre- and post-treatment MRI images were reviewed using a proforma for predefined features and response criteria. ymrT0 was defined as the absence of residual abnormality on MRI.

RESULTS

Twenty patients were included in the study. Seven (35%) ypT0 tumours were ymrT0. All 13 ypT0 tumours not achieving ymrT0 appearances had a good radiological response, with at least 65% tumour reduction. The appearances were heterogeneous: in 11/13 patients the tumour was replaced by a region of at least 50% low signal on MRI, with 8/13 having ≥80% low signal, and 3/13 with 100% low signal.

CONCLUSION

MRI may be useful in identifying a complete histopathological response. However, the MRI appearances of ypT0 tumours are heterogeneous and conventional MRI complete response criteria will not detect the majority of patients with a complete histopathological response.

Is local excision after complete pathological response to neoadjuvant chemoradiation for rectal cancer an acceptable treatment option?

PURPOSE

The role of local excision in patients with good histological response to neoadjuvant chemoradiation for locally advanced rectal cancer is unclear, mainly because of possible regional nodal involvement. This study aims to evaluate the correlation between pathological T and N stages following neoadjuvant chemoradiation for locally advanced rectal cancer and the outcome of patients with mural pathological complete response undergoing local excision.

METHODS

This investigation was conducted as a retrospective analysis. Between January 1997 and December 2007, 320 patients with T3 to 4Nx, TxN+ or distal (≤ 6 cm from the anus) T2N0 rectal cancer underwent neoadjuvant concurrent chemoradiation followed by surgery. Radiotherapy was standard and chemotherapy consisted of common fluoropyrimidine-based regimens.

RESULTS

After chemoradiation, 93% patients had radical surgery, 6% had local excision, and 3% did not have surgery. In the 291 patients undergoing radical surgery, the pathological T stage correlated with the N stage (P = .036). We compared the outcome of patients with mural complete pathological response (n = 37) who underwent radical surgery (group I) and those (n = 14) who had local excision only (group II). With a median follow-up of 48 months, 4 patients in group I had a recurrence and none in group II had a recurrence; one patient died in group I and none died in group II. Disease-free survival, pelvic recurrence-free survival, and overall survival rates were similar in both groups.

CONCLUSION

In this retrospective study, nodal metastases were rare in patients with mural complete pathological response following neoadjuvant chemoradiation (3%), and local excision did not compromise their outcome. Therefore, local excision may be an acceptable option in these patients.

The indication and surgical results of local excision following radiotherapy for low rectal cancer

AIM

Radical surgery of rectal cancer is associated with significant morbidity, and some patients with low-lying lesions must accept a permanent colostomy. The objective of this study was to evaluate the outcome of local excision followed by adjuvant radiotherapy for rectal cancer for curative purposes.

METHOD

One hundred and seven patients with rectal carcinoma performed with local excision were analysed retrospectively.

RESULTS

The procedures of local excision were trans-anal resection in 83 patients, trans-sacral resection in 16, trans-sphincteric local resection in five, and trans-vaginal resection in three. The overall disease-free survival rate was 80.4% (86/107), including 90.0% (54/60) for T1 and 72.3% (34/47) for T2 tumours, respectively. Eighty-two of 107 patients underwent adjuvant postoperative radiotherapy after local excision, and 25 did not, and the DFS rates between radiation and nonradiation group were significantly different for T2 [81.6% (31/38) vs 33.3% (3/9), P < 0.05], but not for T1 tumours (90.9%vs 87.5%, P > 0.05). The rates of local recurrence and distant metastasis were 13.1% (14/107) and 4.7% (5/106), respectively, and the median time to relapse was 15 months (range: 10-53) for local recurrence and 30 months (21-65) for distant recurrence. The risk factors for local recurrence were large tumour (≥3 cm), poorly differentiated adenocarcinoma and T2 tumour.

CONCLUSIONS

Local excision followed adjuvant radiotherapy is an alternative and feasible technique for small T1 rectal cancer in selected cases.

Mast cell degranulation is essential for anastomotic healing in well perfused and poorly perfused rat colon

BACKGROUND

Mast cell degranulation is an important step in early wound healing in the skin however the role of the mast cell in anastomotic healing is less clear. The aim of this study was to investigate the importance of mast cell degranulation in anastomotic healing and to assess whether a promoter of mast cell degranulation could increase anastomotic healing in poorly perfused bowel.

METHODS

Fifty Wistar rats were divided into five groups: control, normally perfused bowel with mast cell stabilisation, normally perfused bowel with mast cell degranulation, hypoperfused bowel, and hypoperfused bowel with mast cell degranulation. A colo-colonic anastomosis was formed in each animal. Four d later, following sacrifice, the strength of the anastomosis was assessed in each animal.

RESULTS

Mast cell stabilisation reduced anastomotic healing in normally perfused bowel (P < 0.001). Hypoperfused bowel resulted in reduced anastomotic strength (P < 0.001) however the addition of a mast cell degranulating agent increased healing in hypoperfused bowel to levels comparable with control.

CONCLUSIONS

Mast cell degranulation is essential for early anastomotic healing. Healing is reduced in hypoperfused bowel but the administration of a mast cell degranulation agent can compensate for the adverse effects of a poor blood supply on anastomotic healing.

Treatment for patients with rectal cancer and a clinical complete response to neoadjuvant therapy: a decision analysis

PURPOSE

A clinical complete response to neoadjuvant therapy occurs in a subset of patients with rectal cancer. Management of these patients is controversial and tension exists between the recurrence risk with observation, and the impact of surgery on quality-of-life. Therefore, the objective was to develop a decision-analytic model to evaluate the relative benefits of surgery vs. observation in rectal cancer patients who achieve clinical complete response after neoadjuvant chemoradiation.

METHODS

Clinically relevant inputs and events, including the ability to identify complete responders, likelihood of relapse and of salvage surgery after relapse, and utilities for each health state, were simulated by use of a Markov state-transition model. Transition probabilities and health-state utilities were derived from the literature and expert consensus. One-way and two-way sensitivity analyses were performed to assess the robustness of model results to assumptions. The primary outcome was quality-adjusted life expectancy.

RESULTS

In the base-case analysis, the quality-adjusted life expectancy with surgery exceeded observation (5.63 vs. 5.34 quality-adjusted life-years). Sensitivity analysis demonstrated that observation was preferred to surgery if the ability to correctly identify patients with true complete responses exceeded 58 percent, if quality-of-life after surgery was poor (utility <0.81), or if the relative reduction in recurrence risk with surgery was <43 percent when compared with observation.

CONCLUSIONS

Our model outlines the issues associated with surgery vs. observation, and suggests that surgery is beneficial for the average patient with rectal cancer with a clinical complete response after neoadjuvant therapy. Current limitations in the clinical assessment of patient response to chemoradiation constitute an important factor influencing our results, and therefore warrant further investigation.

Long-term results of transanal excision after neoadjuvant chemoradiation for T2 and T3 adenocarcinomas of the rectum

INTRODUCTION

Traditionally, selected early distal rectal cancers have been considered for treatment by transanal excision (TAE) with acceptable oncologic results. With the frequent use of neoadjuvant chemoradiation (NCR) for the treatment of locally advanced rectal cancer, there is growing interest in the application of TAE for such lesions. We report our experience of TAE for T2 and T3 rectal cancers following NCR.

MATERIAL AND METHODS

Between July 1994 and August 2006, 44 patients were identified as having undergone full-thickness TAE of pretreatment ultrasound-staged T2 and T3 rectal cancers that were treated with NCR. Fifteen patients were deemed medically unfit for radical resection, and 29 would have required abdominoperineal resection but were opposed to colostomy.

RESULTS

Our patient population consisted of 26 men and 18 women, with a median age of 69 (range, 43-89) and a median follow up of 64 months (6-153). Thirty-one patients had a clinical complete response (cCR) to NCR of which 19 (61%) had a pathologic CR (pCR). Seven (16%) of 44 patients sustained disease recurrence of which two were local only, two local and systemic, and three systemic only. Only four (9%) patients had died of disease at current follow up. Overall 5-year survival rates for T2/T3N0 and T2/T3N1 patients were 84% and 81%, respectively. Five patients underwent radical resection immediately following TAE for either positive margins or residual cancer. There was minimal morbidity with no perioperative mortality associated with TAE.

CONCLUSIONS

TAE of T2 and T3 rectal cancers following NCR is a safe alternative to radical resection in a highly select group of patients for which recurrence and survival rates comparable to radical resection can be achieved. This study supports ongoing efforts to assess this approach in prospective, multi-center trials.

Accuracy of endorectal ultrasonography and computed tomography for restaging rectal cancer after preoperative chemoradiation

BACKGROUND

Preoperative restaging of irradiated rectal cancer is essential for the planning of optimal therapy. The aim of this study was to compare the accuracy of endorectal ultrasonography (ERUS) and CT in restaging rectal cancer after preoperative chemoradiation and to evaluate the factors affecting the accuracy of ERUS.

STUDY DESIGN

Eighty-three patients with initial, locally advanced rectal cancer were prospectively evaluated by ERUS (n=60) and CT (n=80) after preoperative chemoradiation and just before surgery. All patients then underwent subsequent surgical resection and complete pathologic staging.

RESULTS

In restaging the depth of invasion, the overall accuracy was 38.3% (23 of 60) by ERUS and 46.3% (37 of 80) by CT. Overstaging was more common than understaging with both imaging modalities. Accuracy for restaging lymph node metastasis was 72.6% (37 of 51) by ERUS and 70.4% (50 of 71) by CT. The predictive value of node-negative cases by ERUS was somewhat lower than that of CT (81.1% versus 85.4%, respectively). Complete pathology-proved remission was not correctly predicted in any of the 11 patients by any imaging modalities. Pathologic T and N staging correlated with the staging accuracy of ERUS (p=0.028 and p=0.001, respectively).

CONCLUSIONS

ERUS and CT may allow good prediction of node-negative rectal cancers, although they are inaccurate modalities for predicting treatment response on the rectal wall. New methods of interpretation and diagnostic criteria for ERUS and CT are essential for increasing the accuracy of cancer prediction in at-risk patients.

TEM/local excision: indications, techniques, outcomes, and the future

Transanal endoscopic microsurgery (TEM) has emerged as a safe method for excising virtually any rectal adenoma and carefully selected cancers. Extended applications include treatment of extra- and supra-sphincteric fistulae, rectovaginal fistulae, anastomotic strictures, and sinus tracts. The procedure utilizes an air-tight system, long shafted instruments, high-quality magnifying optics, and constant carbon dioxide insufflation, all of which facilitate a precise excision and closure with clear margins. Complications are few, most patients can be treated as an outpatient.

The role of radiation therapy for colorectal cancer

Radiation therapy (RT) has been used to treat cancers for more than a century. Recent randomized trials have helped clarify the treatment recommendations in the use of RT for colorectal cancers. This article reviews these trials to illustrate key concepts, places these trials in perspective, and provides direction for future research.

Complete clinical response after preoperative chemoradiation in rectal cancer: is a "wait and see" policy justified?

PURPOSE

A proportion of patients, who receive preoperative chemoradiation for locally advanced (T3, T4, NX) rectal cancer achieve a complete clinical response and a pathologic complete response in the region of 15 to 30 percent. Support is growing in the United Kingdom for the concept of "waiting to see" and not proceeding to radical surgery when a complete clinical response is observed. The purpose of this review was to use a literature search to assess how often complete clinical response is achieved after neoadjuvant chemoradiation, the concordance of this finding with pathologic complete response, and to determine whether it is feasible to observe patients who achieve complete clinical response rather than proceed to surgery.

RESULTS

In total, 218 Phase I/II or retrospective studies and 28 Phase III trials of preoperative radiotherapy or chemoradiation were identified: 96 percent of trials documented the pathologic complete response, but only 38 trials presented data on the achievement of a complete clinical response/partial clinical response. Only five studies were found in which patients with clinically staged T2/T3 tumors were treated with radiotherapy/chemoradiation and did not routinely proceed to surgery and also reported on the long-term outcome of a "wait and see" policy.

DISCUSSION

It remains uncertain whether the degree of response to chemoradiation in terms of complete clinical response or pathologic complete response is a useful clinical end point. Studies that include T3 rectal cancer are associated with high local recurrence rates after nonsurgical treatment. Few studies report long-term outcome after achievement of a complete clinical response.

CONCLUSIONS

The end point of complete clinical response is inconsistently defined and seems insufficiently robust with only partial concordance with pathologic complete response. The rationale of a "wait and see" policy when complete clinical response status is achieved relies on retrospective observations, which are currently insufficient to support this policy except in patients who are recognized to be unfit for or refuse radical surgery.

Neoadjuvant chemoradiation and local excision for T2-3 rectal cancer

BACKGROUND

Local excision (LE) of T1 low-risk (G1-2/L0/V0) rectal cancer is an established approach with local recurrence (LR) rates of approximately 5%, whereas LE of > or = T2 high-risk tumors or inadequate resections (R1/RX/R < or = 1 mm) showed high recurrence rates. Because of the favorable results after neoadjuvant chemoradiotherapy (nCRT) and radical surgery of disease that completely responds (CR) with almost absent LR even of T3-4 tumors, an extension of the indication for LE is controversially discussed, and therefore, we assessed this therapeutic option.

METHODS

Including our own data, seven studies about LE after nCRT of cT2-3 tumors (n = 237) were analyzed after a PubMed search for cT categories, tumor height, nCRT regimens, schedule and technique of surgery, complications, freedom of stoma, response rates (ypT0-3), length of follow-up, LR, and metastases.

RESULTS

Subgroups that we formed (retrospective vs. prospective/retractor vs. transanal endoscopic microsurgery) showed differences in the distribution of cT categories. However, neither the studies we considered nor our own patients showed LR in CR (ypT0). In addition, patients with ypT1 tumor consistently showed low LR rates of 2% (range, 0%-6%), whereas in ypT2 findings, less favorable LR rates of 6% to 20% were observed, and disease that did not respond to therapy (ypT3) displayed LR rates in up to 42%.

CONCLUSIONS

Despite of a highly selected patient collective, an extended indication for LE of cT2-3 rectal cancer after nCRT may be considered. The strongest prognostic factors were a CR (ypT0) or responses on submucosa level (ypT1). These first results will have to be confirmed in a prospective trial with an appropriate sample size to ensure high statistical power.

The multidisciplinary management of gastrointestinal cancer. Multimodal treatment of rectal cancer

Greater understanding of the natural history of rectal cancer, and the knowledge that a histologically involved circumferential margin due to inadequate lateral dissection confers a high risk of local recurrence have driven technical advances in surgical technique with meticulous surgical dissection along embryological planes. Significant improvements in local control and overall survival have been seen for patients with resectable rectal cancer. However, even high-quality surgery cannot always achieve a curative resection for locally advanced cancers that extend below the levators, having transgressed the mesorectal fascia. Magnetic resonance imaging is now accepted as a practical method of clinical staging, and can accurately predict pre-operatively the likelihood of achieving a clear circumferential margin. Technological advances in radiation planning and new effective cytotoxic drugs also give scope for dealing with unresectable rectal cancer, and the potential for controlling distant micrometastases. Hence, modern multimodal treatment of rectal cancer attempts to integrate surgery, radiotherapy and chemotherapy, and address the two distinct problems of local recurrence and metastatic disease. Multidisciplinary teams achieve the best results. This paper discusses the surgical management of rectal cancer, the pathology, the principles of imaging, and the lessons learnt from randomized trials of radiotherapy and chemoradiation.