Does rectal wall tumor eradication with preoperative chemoradiation permit a change in the operative strategy?

Predictors of Nodal Disease in Rectal Cancer Patients with Complete Mucosal Response to Neoadjuvant Therapy

BACKGROUND

Some patients with locally advanced rectal cancer (LARC) achieve complete mucosal response following neoadjuvant therapy (NAT) and may be candidates for watch and wait strategy. This study aimed to identify predictors of nodal disease in patients with LARC who had a complete mucosal response to NAT.

METHODS

This case-control study included patients with LARC who were treated with NAT in the National Cancer Database between 2004 and 2019. Patients with complete mucosal response, defined as pathologic T0, were identified and classified according to the status of the pathologic N stage into complete response (pT0, pN0) and complete mucosal response with positive nodal disease (pT0, pN +). The two groups were compared regarding baseline demographics and tumor characteristics to determine the predictors of nodal disease after NAT.

RESULTS

A total of 5529 patients (59.7% male) with a mean age of 59.6 ± 12.2 years had a complete mucosal response following NAT. Nodal disease was detected in 443 (8%) patients with a complete mucosal response. Independent predictors of nodal disease were clinical N + stage (OR: 1.87, p < 0.001), mucinous histology (OR: 3.8, p = 0.003), and lymphovascular invasion (OR = 4.01, p < 0.001). The clinical T stage was inversely related to the risk of nodal disease.

CONCLUSIONS

Despite having a complete mucosal response following NAT, 8% of patients had nodal disease. Clinical evidence of nodal involvement on preoperative assessment, mucinous tumor histology, and lymphovascular invasion predicted nodal disease after NAT. These findings should be considered when making a decision on watch and wait strategy in patients with clinical complete response.

Transanal Endoscopic Microsurgery Versus Total Mesorectal Excision in ypT0-1 Rectal Cancer After Preoperative Radiochemotherapy: Postoperative Morbidity, Functional Results, and Long-term Oncologic Outcome

BACKGROUND

In patients with locally advanced extraperitoneal rectal cancer, a multidisciplinary approach represents the standard treatment. However, considering the favorable prognosis in patients with major or complete response, radical surgery might represent overtreatment.

OBJECTIVE

This study aimed to evaluate postoperative short-term morbidity, functional outcome, and oncologic long-term outcome in patients with rectal cancer treated with local excision by transanal endoscopic microsurgery or radical surgery and to determine who achieved a complete or major pathological response (ypT0-1) after neoadjuvant treatment.

DESIGN

This was a retrospective study.

SETTING

The study was conducted at a single center.

PATIENTS

Patients who had received neoadjuvant treatment by local excision with a major or complete pathological response at histological examination (transanal endoscopic microsurgery group) were compared to patients treated by radical surgery with the same pathological response (total mesorectal excision group).

INTERVENTIONS

The interventions included local excision by transanal endoscopic microsurgery and radical surgery with total mesorectal excision.

MAIN OUTCOME MEASURES

Postoperative short-term morbidity, functional outcome 1 year after surgery, and oncologic long-term outcome were measured.

RESULTS

Ninety-three patients were included in the study (35 in the transanal endoscopic microsurgery group and 58 in the mesorectal excision group). In the total mesorectal excision group, a sphincter-saving approach was possible in 89.7% (vs 100%; p = 0.049); a protective temporary stoma was necessary in 74.1% of radical procedures (vs 0%; p < 0.001), and 13.8% of these became permanent. Short-term postoperative morbidity was lower after local excision (14.3% vs 46.6%; p = 0.002). One year after surgery, the transanal endoscopic microsurgery group recorded better evacuation and continence function than the total mesorectal excision group. Oncologic outcome was similar between the groups.

LIMITATIONS

This study had a retrospective design.

CONCLUSION

If a major or complete pathological response occurs after neoadjuvant treatment, an organ-sparing approach by local excision seems to offer the same oncologic results as radical surgery, but it has a better postoperative morbidity rate and better functional results. See Video Abstract at http://links.lww.com/DCR/B901 .Microcirugía endoscópica transanal versus escisión total del mesorrecto en cáncer de recto ypT0-1 después de radioquimioterapia preoperatoria: morbilidad posoperatoria, resultados funcionales y resultado oncológico a largo plazo.

ANTECEDENTES

En pacientes con cáncer rectal extraperitoneal localmente avanzado, un abordaje multidisciplinario con radioquimioterapia preoperatoria y cirugía con escisión total del mesorrecto representa el tratamiento estándar. En pacientes que obtienen una respuesta mayor o completa, la cirugía radical puede representar un sobretratamiento, considerando el pronóstico favorable de estos casos.

OBJETIVO

Evaluar la morbilidad posoperatoria a corto plazo, el resultado funcional y el resultado oncológico a largo plazo en pacientes con cáncer de recto tratados con escisión local mediante microcirugía endoscópica transanal o mediante cirugía radical y que obtuvieron una respuesta patológica completa o mayor (ypT0-1) después del tratamiento neoadyuvante.

DISEO

Este fue un estudio retrospectivo.

AJUSTE

El estudio se realizó en un solo centro.

ESCENARIO

El estudio se realizó en un solo centro.

PACIENTES

Se comparó a los pacientes tratados, tras tratamiento neoadyuvante (1996-2016), mediante escisión local con respuesta patológica mayor o completa al examen histológico (grupo de microcirugía endoscópica transanal), con los pacientes tratados mediante cirugía radical con la misma respuesta patológica (grupo de escisión mesorrectal total).

INTERVENCIONES

Extirpación local mediante microcirugía endoscópica transanal y cirugía radical con escisión mesorrectal total.

PRINCIPALES MEDIDAS DE RESULTADO

Morbilidad posoperatoria a corto plazo, resultado funcional a un año después de la cirugía (evaluado con una puntuación de evacuación y continencia) y resultado oncológico a largo plazo.

LIMITACIONES

Las limitaciones de este estudio incluyen su diseño retrospectivo.

CONCLUSIN

Si se produce una respuesta patológica mayor o completa después del tratamiento neoadyuvante, un abordaje con preservación de órganos mediante escisión local parece ofrecer los mismos resultados oncológicos que la cirugía radical, pero tiene una menor tasa de morbilidad postoperatoria y mejores resultados funcionales un año después de la cirugía. Consulte Video Resumen en http://links.lww.com/DCR/B901 . (Traducción-Dr. Felipe Bellolio ).

Rectal Sparing Approach After Neoadjuvant Therapy in Patients with Rectal Cancer: The Preliminary Results of the ReSARCh Trial

BACKGROUND

Rectum-preservation for locally advanced rectal cancer has been proposed as an alternative to total mesorectal excision (TME) in patients with major (mCR) or complete clinical response (cCR) after neoadjuvant therapy. The purpose of this study was to report on the short-term outcomes of ReSARCh (Rectal Sparing Approach after preoperative Radio- and/or Chemotherapy) trial, which is a prospective, multicenter, observational trial that investigated the role of transanal local excision (LE) and watch-and-wait (WW) as integrated approaches after neoadjuvant therapy for rectal cancer.

METHODS

Patients with mid-low rectal cancer who achieved mCR or cCR after neoadjuvant therapy and were fit for major surgery were enrolled. Clinical response was evaluated at 8 and 12 weeks after completion of chemoradiotherapy. Treatment approach, incidence, and reasons for subsequent TME were recorded.

RESULTS

From 2016 to 2019, 160 patients were enrolled; mCR or cCR at 12 weeks was achieved in 64 and 96 of patients, respectively. Overall, 98 patients were managed with LE and 62 with WW. In the LE group, Clavien-Dindo 3+ complications occurred in three patients. The rate of cCR increased from 8- to 12-week restaging. Thirty-three (94.3%) of 35 patients with cCR had ypT0-1 tumor. At a median 24 months follow-up, a tumor regrowth was found in 15 (24.2%) patients undergoing WW.

CONCLUSIONS

LE for patients achieving cCR or mCR is safe. A 12-week interval from chemoradiotherapy completion to LE is correlated with an increased cCR rate. The risk of ypT > is reduced when LE is performed after cCR.

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.

Transanal endoscopic microsurgery after neoadjuvant radiochemotherapy for locally advanced extraperitoneal rectal cancer

PURPOSE

The aim of this study is to provide a prospective analysis of post-operative and oncological outcomes in patients affected by locally advanced rectal cancer (LARC), who obtained a major/complete clinical response after pre-operative radio-chemotherapy (RCT) and were treated with local excision (LE) by trans-anal endoscopic microsurgery (TEM) to confirm a pathological complete response (pCR) after to neo-adjuvant RCT.

METHODS

All patients with LARC treated by pre-operative RCT and full-thickness LE by TEM (2000-2014) were included in the study. If the pathological analysis confirmed near complete or pCR, intensive follow up was proposed. If the pathological response was incomplete, a radical resection with TME was proposed. Post-operative (according to Clavien's classification), functional and long-term oncological outcome were analyzed.

RESULTS

36 patients were treated by TEM. The median post-operative hospital stay was 5 days. The post-operative morbidity was 41.6% (no grade ≥3). At pathological analysis, 23 specimens were ypT0 TRG1, and 4 were ypT1 TRG2. In 9 cases (ypT>1 and/or TRG>2), radical surgery with TME was proposed but 3 refused it. Median follow-up was 68 months. One local recurrence and 4 distant metastases occurred. The 5-yr actuarial local control, overall survival and disease-free survival were 96.0%, 92.0% and 82.8%.

CONCLUSIONS

In case of major or complete clinical response of LARC after pre-operative RCT, LE by TEM can be used to confirm the pathological response. This avoids the necessity of radical surgery and, in our experience, this approach seems to guarantee oncological safety with the functional advantages of an organ-sparing procedure.

Magnetic resonance based texture parameters as potential imaging biomarkers for predicting long-term survival in locally advanced rectal cancer treated by chemoradiotherapy

AIM

The study aimed to investigate whether textural features of rectal cancer on MRI can predict long-term survival in patients treated with long-course chemoradiotherapy.

METHOD

Textural analysis (TA) using a filtration-histogram technique of T2-weighted pre- and 6-week post-chemoradiotherapy MRI was undertaken using TexRAD, a proprietary software algorithm. Regions of interest enclosing the largest cross-sectional area of the tumour were manually delineated on the axial images and the filtration step extracted features at different anatomical scales (fine, medium and coarse) followed by quantification of statistical features [mean intensity, standard deviation, entropy, skewness, kurtosis and mean of positive pixels (MPP)] using histogram analysis. Cox multiple regression analysis determined which univariate features including textural, radiological and histological independently predicted overall survival (OS), disease-free survival (DFS) and recurrence-free survival (RFS).

RESULTS

MPP [fine texture, hazard ratio (HR) 6.9, 95% CI: 2.43-19.55, P < 0.001], mean (medium texture, HR 5.6, 95% CI: 1.4-21.7, P = 0.007) and extramural venous invasion (EMVI) on MRI (HR 2.96, 95% CI: 1.04-8.37, P = 0.041) independently predicted OS while mean (medium texture, HR 4.53, 95% CI: 1.58-12.94, P = 0.003), MPP (fine texture, HR 3.36, 95% CI: 1.36-8.31, P = 0.008) and threatened circumferential resection margin (CRM) on MRI (HR 3.1, 95% CI: 1.01-9.46, P = 0.046) predicted DFS. For OS, EMVI on MRI (HR 4.23, 95% CI: 1.41-12.69, P = 0.01) and for DFS kurtosis (medium texture, HR 3.97, 95% CI: 1.44-10.94, P = 0.007) and CRM involvement on MRI (HR 3.36, 95% CI: 1.21-9.32, P = 0.02) were the independent post-treatment factors. Only TA independently predicted RFS on pre- or post-treatment analyses.

CONCLUSION

MR based TA of rectal cancers can predict outcome before undergoing surgery and could potentially select patients for individualized therapy.

Optimal therapy for resectable rectal cancer

A lot can be gained by improving our understanding of the optimal sequence of existing therapies in rectal cancer, with the more difficult task of balancing the morbidity of recurrence with the morbidity of prescribed therapies that are particularly toxic owing to tumour location. This review aims to highlight a recent shift in treatment strategies in the opposite direction, with a focus on earlier, more intense systemic treatments with reduced local therapies. Understanding the rationale for and evidence to support this shift will help identify gaps, shape future trials, and ultimately answer the question of whether this is indeed the right path to follow with regards to maintaining local control rates and long-term outcomes for patients, and improving distal disease control and local treatment-related morbidities without compromising quality of life.

Predictors of Pathologic Complete Response Following Neoadjuvant Chemoradiotherapy for Rectal Cancer

BACKGROUND

Some patients with rectal cancer who receive neoadjuvant chemoradiotherapy (nCRT) achieve a pathologic complete response (pCR) and may be eligible for less radical surgery or non-operative management. The aim of this study was to identify variables that predict pCR after nCRT for rectal cancer and to examine the impact of pCR on postoperative complications.

METHODS

A retrospective review was performed of the NCDB from 2006 to 2011. Patients with rectal cancer who received nCRT followed by radical resection were included in this study. Multivariable analysis of the association between clinicopathologic characteristics and pCR was performed, and propensity-adjusted analysis was used to identify differences in postoperative morbidity between pCR and non-pCR patients.

RESULTS

A total of 23,747 patients were included in the study. Factors associated with pCR included lower tumor grade, lower clinical T and N stage, higher radiation dose, and delaying surgery by more than 6-8 weeks after the end of radiation, while lack of health insurance was linked with a lower likelihood of pCR. Complete response was not associated with an increased risk of major postoperative complications.

CONCLUSIONS

Several clinical, pathologic, and treatment variables can help to predict which patients are most likely to have pCR after nCRT for rectal cancer. Awareness of these variables can be valuable in counseling patients regarding prognosis and treatment options.

Pathologic Assessment of Rectal Carcinoma after Neoadjuvant Radio(chemo)therapy: Prognostic Implications

Neoadjuvant radio(chemo)therapy is increasingly used in rectal cancer and induces a number of morphologic changes that affect prognostication after curative surgery, thereby creating new challenges for surgical pathologists, particularly in evaluating morphologic changes and tumour response to preoperative treatment. Surgical pathologists play an important role in determining the many facets of rectal carcinoma patient care after neoadjuvant treatment. These range from proper handling of macroscopic specimens to accurate microscopic evaluation of pathological features associated with patients' prognosis. This review presents the well-established pathological prognostic indicators and discusses challenging features in order to provide both surgical pathologists and treating physicians with a checklist that is useful in a neoadjuvant setting.

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.

Chemoradiation therapy for rectal cancer in the distal rectum followed by organ-sparing transanal endoscopic microsurgery (CARTS study)

BACKGROUND

This prospective multicentre study was performed to quantify the number of patients with minimal residual disease (ypT0-1) after neoadjuvant chemoradiotherapy and transanal endoscopic microsurgery (TEM) for rectal cancer.

METHODS

Patients with clinically staged T1-3 N0 distal rectal cancer were treated with long-course chemoradiotherapy. Clinical response was evaluated 6-8 weeks later and TEM performed. Total mesorectal excision was advocated in patients with residual disease (ypT2 or more).

RESULTS

The clinical stage was cT1 N0 in ten patients, cT2 N0 in 29 and cT3 N0 in 16 patients. Chemoradiotherapy-related complications of at least grade 3 occurred in 23 of 55 patients, with two deaths from toxicity, and two patients did not have TEM or major surgery. Among 47 patients who had TEM, ypT0-1 disease was found in 30, ypT0 N1 in one, ypT2 in 15 and ypT3 in one. Local recurrence developed in three of the nine patients with ypT2 tumours who declined further surgery. Postoperative complications grade I-IIIb occurred in 13 of 47 patients after TEM and in five of 12 after (completion) surgery. After a median follow-up of 17 months, four local recurrences had developed overall, three in patients with ypT2 and one with ypT1 disease.

CONCLUSION

TEM after chemoradiotherapy enabled organ preservation in one-half of the patients with rectal cancer.

Endoscopic evaluation of clinical response after preoperative chemoradiotherapy for lower rectal cancer: the significance of endoscopic complete response

PURPOSE

The management of rectal cancer is a significant oncologic challenge because rectal cancer has a poor prognosis among the various types of colorectal cancer. There have been several recent reports on a nonoperative approach for advanced lower rectal cancer, and this may be best for local disease control. However, objective evaluation of tumor response after preoperative chemoradiotherapy has not been standardized. The purpose of this study is to evaluate our method of endoscopic evaluation of complete response.

METHODS

This is a retrospective chart review. All patients received a long course of preoperative chemoradiotherapy (5-fluorouracil-based chemotherapy and 45-50.4 Gy) followed by radical surgical resection from May 2005 to March 2012 in The Cancer Institute Hospital of Japanese Foundation for Cancer Research. One hundred fifty-seven patients were reviewed consecutively. Criteria for endoscopic complete response were defined with a focus on the degree of ulcer healing and pit pattern without magnification.

RESULTS

Endoscopic CR (E-CR) evaluation with our definitions reflected histopathologic response evaluation with an accuracy of 91.7 %, sensitivity of 27.8 %, specificity of 100 %, positive predictive value (PPV) of 100 %, and negative predictive value (NPV) of 91.4 % (p < 0.001). Our criteria of E-CR led all cases of y-clinical CR (ycCR) to pathological CR.

CONCLUSIONS

Endoscopic evaluation focused on the degree of ulcer healing, and pit pattern without magnification is useful for judging ycCR.

Immediate surgery or clinical follow-up after a complete clinical response?

Neoadjuvant chemoradiation (CRT) is considered as one of the preferred treatment strategies for patients with locally advanced rectal cancer. This treatment strategy may lead to significant tumor regression, ultimately leading to complete pathological response in up to 42% of patients. Assessment of tumor response following CRT and before radical surgery may identify patients with complete clinical response that could be managed non operatively with strict follow-up (Watch & Wait Strategy).

Less than 12 nodes in the surgical specimen after total mesorectal excision following neoadjuvant chemoradiation: it means more than you think!

BACKGROUND

A minimum of 12 examined lymph nodes (LN) is recommended to ensure adequate staging and oncologic resection of patients undergoing proctectomy for rectal adenocarcinoma. However, a decreased number of LN is not unusual in patients receiving neoadjuvant chemoradiation.

PURPOSE

We hypothesized that a decreased number of LN in the proctectomy specimen of these patients may be an indicator of tumor response and be associated with improved prognosis.

METHODS

A single-center colorectal cancer database was queried for c-stage II-III rectal cancer patients undergoing neoadjuvant chemoradiation followed by proctectomy between 1997 and 2007. Patients were categorized into two groups according to the number of LN retrieved from the proctectomy specimen: <12 LN versus ≥12 LN. Groups were compared with respect to demographics, tumor and treatment characteristics, and the following oncologic outcomes: overall-survival (OS), cancer-specific-mortality (CSM), cancer-free-survival (CFS), distant (DR), and local recurrences (LR).

RESULTS

The query returned 237 patients. There were 173 (73 %) males, and the median age was 57 years [interquartile range (IQR) 49-66 years]. The median number of LN retrieved was 15 (IQR 10-23) and 70 (30 %) patients had less than 12 nodes examined. The <12 nodes group was older [60 (IQR 51-71 years) vs. 55 (IQR 48-65 years), p = 0.009] and had more pathologic complete responders (36 vs. 19 %, p = 0.01). No <12 nodes patient experienced a LR, whereas the 5-year LR rate was 11 % in the ≥12 nodes group (p = 0.004). Other oncologic outcomes were not significantly different.

CONCLUSIONS

Retrieval of less than 12 nodes in the proctectomy specimen of rectal cancer patients treated with neoadjuvant chemoradiation does not affect OS, CSM, CFS, or DR and may be a marker of higher tumor response and, consequently, decreased LR rate.

Organ-preserving therapy for rectal cancer

SUMMARY Total mesorectal excision has resulted in low local recurrence rates in rectal cancer patients; however, it is associated with a significant impairment in quality of life. The operation may be disfiguring and cause permanent effects on gastrointestinal, genitourinary and sexual function. Recently, researchers have identified subgroups of rectal cancer patients who may be able to forgo total mesorectal excision without compromising their oncological outcomes. Two groups of patients are candidates for organ preservation: those with early-stage disease that may be adequately addressed by a more limited resection, and those with locally advanced disease that has responded completely to neoadjuvant therapy. Additionally, radiation alone may be curative in both early and locally advanced disease. This article reviews the data regarding these approaches.

Update and debate issues in surgical treatment of middle and low rectal cancer

Based on a review of the literature, this paper provides an update on surgical treatment of middle and low rectal cancer and discusses issues of debate surrounding that treatment. The main goal of the surgical treatment of rectal cancer is radical resection of the tumor and surrounding lymphatic tissue. Local excision of early rectal cancer can be another treatment option, in which the patient can avoid possible complications related to radical surgery. Neoadjuvant chemoradiation therapy (CRT) has been recommended for patients with cT3-4N0 or any T N+ rectal cancer because CRT shows better local control and less toxicity than adjuvant CRT. However, recent clinical trials showed promising results for local excision after neoadjuvant CRT in selected patients with low rectal cancer. In addition, the "wait and see" concept is another modality that has been reported for the management of tumors that show complete clinical remission after neoadjuvant CRT. Although radical surgery for middle and low rectal cancer is the cornerstone therapy, an ultralow anterior resection with or without intersphincteric resection (ISR) has become an alternative standard surgical method for selected patients. Many studies have reported on the oncological safety of the ISR, but few of them have addressed the issue the functional outcome. Furthermore, an abdominoperineal resection (APR) has problems with high rates of tumor perforations and positive circumferential resection margins, and those factors have contributed to its having a high rate of local recurrence and a poor survival rate for rectal cancer compared with sphincter-saving procedures. Recently, great efforts have been made to reduce these problems, and the total levator excision or the extended APR concept has emerged. Surgical management for low rectal cancer should aim to radically excise the tumor and to preserve as much of the sphincter function as possible by using multidisciplinary approaches. However, further prospective clinical trials are needed for tailored treatment of rectal cancer patients.

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.

Systemic Chemotherapy prior to Cytoreductive Surgery and HIPEC for Carcinomatosis from Appendix Cancer: Impact on Perioperative Outcomes and Short-Term Survival

Background and Objectives. Systemic chemotherapy administered prior to cytoreductive surgery and hyperthermic intraperitoneal chemotherapy (HIPEC) for peritoneal mucinous adenocarcinoma of appendiceal origin (PMCA) is associated with a significant rate of histological response. The impact of preoperative systemic chemotherapy (PSC) on intraperitoneal tumor burden, completeness of cytoreduction, and perioperative complications is unknown. Methods. We analyzed prospectively collected data from our HIPEC database. Thirty-four patients with PMCA were prospectively recruited and treated with PSC. Perioperative variables and survival in this group of patients were compared against 24 patients with PMCA who did not receive PSC. Results. Ten of 34 patients (29%) receiving PSC had a complete or near complete histological response. Patients receiving PSC had a lower peritoneal carcinomatosis index, required fewer peritonectomies and visceral resections, and achieved complete cytoreduction more frequently compared to patients with no preoperative chemotherapy. The incidence of perioperative complications and survival were not significantly different between the two groups. However, patients with complete histological response had better overall survival compared to patients without complete response. Conclusions. Preoperative systemic chemotherapy in appendix-originated PMCA is associated with a significant rate of histological response which may reduce the tumor burden, facilitate less aggressive and more complete CRS, and improve short-term survival in patients with a significant histological response.

Shifting concepts in rectal cancer management: a review of contemporary primary rectal cancer treatment strategies

The management of rectal cancer has transformed over the last 3 decades and continues to evolve. Some of these changes parallel progress made with other cancers: refinement of surgical technique to improve organ preservation, selective use of neoadjuvant (and adjuvant) therapy, and emergence of criteria suggesting a role for individually tailored therapy. Other changes are driven by fairly unique issues including functional considerations, rectal anatomic features, and surgical technical issues. Further complexity is due to the variety of staging modalities (each with its own limitations), neoadjuvant treatment alternatives, and competing strategies for sequencing multimodal treatment even for nonmetastatic disease. Importantly, observations of tumor response made in the era of neoadjuvant therapy are reshaping some traditionally held concepts about tumor behavior. Frameworks for prioritizing and integrating complex data can help to formulate treatment plans for patients.

Critical appraisal of the 'wait and see' approach in rectal cancer for clinical complete responders after chemoradiation

BACKGROUND

Some 10-20 per cent of patients with locally advanced rectal cancer achieve a pathological complete response (pCR) at surgery following preoperative chemoradiation (CRT). Some demonstrate a sustained clinical complete response (cCR), defined as absence of clinically detectable residual tumour after CRT, and do not undergo resection. The aim of this review was to evaluate non-operative treatment of rectal cancer after CRT, and the outcome of patients observed without radical surgery.

METHODS

A systematic computerized search identified 30 publications (9 series, 650 patients) evaluating a non-operative approach after CRT. Original data were extracted and tabulated, and study quality evaluated. The primary outcome measure was cCR. Secondary outcome measures included locoregional failure rate, disease-free survival and overall survival.

RESULTS

The most recent Habr-Gama series reported a low locoregional failure rate of 4·6 per cent, with 5-year overall and disease-free survival rates of 96 and 72 per cent respectively. These findings were supported by a small prospective Dutch study. However, other retrospective series have described higher recurrence rates. All studies were heterogeneous in staging, inclusion criteria, study design and rigour of follow-up after CRT, which might explain the different outcomes. The definition of cCR was inconsistent, with only partial concordance with pCR. The results suggested that patients who are observed, but subsequently fail to sustain a cCR, may fare worse than those who undergo immediate tumour resection.

CONCLUSION

The rationale of a 'wait and see' policy relies mainly on retrospective observations from a single series. Proof of principle in small low rectal cancers, where clinical assessment is easy, should not be extrapolated uncritically to more advanced cancers where nodal involvement is common. Long-term prospective observational studies with more uniform inclusion criteria are required to evaluate the risk versus benefit.

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.

The CARTS study: Chemoradiation therapy for rectal cancer in the distal rectum followed by organ-sparing transanal endoscopic microsurgery

Background

The CARTS study is a multicenter feasibility study, investigating the role of rectum saving surgery for distal rectal cancer.

Methods/Design

Patients with a clinical T1-3 N0 M0 rectal adenocarcinoma below 10 cm from the anal verge will receive neoadjuvant chemoradiation therapy (25 fractions of 2 Gy with concurrent capecitabine). Transanal Endoscopic Microsurgery (TEM) will be performed 8 - 10 weeks after the end of the preoperative treatment depending on the clinical response.

Primary objective is to determine the number of patients with a (near) complete pathological response after chemoradiation therapy and TEM. Secondary objectives are the local recurrence rate and quality of life after this combined therapeutic modality. A three-step analysis will be performed after 20, 33 and 55 patients to ensure the feasibility of this treatment protocol.

Discussion

The CARTS-study is one of the first prospective multicentre trials to investigate the role of a rectum saving treatment modality using chemoradiation therapy and local excision. The CARTS study is registered at clinicaltrials.gov (NCT01273051)

Can mesorectal lymph node excision be avoided in rectal cancer surgery?

Rectal excision is the standard in rectal cancer treatment. The morbidity of rectal excision, together with the low rate of positive lymph nodes in patients with a good response after radiochemotherapy, raises the challenging concept of organ preservation. Patients with a complete response can benefit from a nonoperative strategy based on a strict follow up. Those with a complete or subcomplete response can be treated by local excision. Limitations in accurately assessing a complete response by conventional and modern imaging modalities suggest that local excision is more appropriate for the majority of patients when organ preservation is being considered. The encouraging results of retrospective series of local excision in downstaged clinical T2/T3 low rectal cancer after radiochemotherapy, however, need to be confirmed by the ongoing multicentre phase II United States and phase III French trials before routinely proposing organ preservation in patients with a good response.

Complete clinical response after neoadjuvant chemoradiation for distal rectal cancer

Multimodality treatment of rectal cancer, with the combination of radiation therapy, chemotherapy, and surgery has become the preferred approach to locally advanced rectal cancer. The use of neoadjuvant chemoradiation therapy (CRT) has resulted in reduced toxicity rates, significant tumor downsizing and downstaging, better chance of sphincter preservation, and improved functional results. A proportion of patients treated with neoadjuvant CRT may ultimately develop complete clinical response. Management of these patients with complete clinical response remains controversial and approaches including radical resection, transanal local excision, and observation alone without immediate surgery have been proposed. The use of strict selection criteria of patients after neoadjuvant CRT has resulted in excellent long-term results with no oncological compromise after observation alone in patients with complete clinical response. Recurrences are detectable by clinical assessment and frequently amenable to salvage procedures.

Pathologic complete response after neoadjuvant treatment for rectal cancer decreases distant recurrence and could eradicate local recurrence

BACKGROUND

The aim of this study was to evaluate the clinical implications of pathologic complete response (pCR) (i.e., T0N0M0) after neoadjuvant chemoradiation and radical surgery in patients with locally advanced rectal cancer.

MATERIALS AND METHODS

A single-center, prospectively maintained colorectal cancer database was queried for patients with primary cII and cIII rectal cancer staged by CT and ERUS/MRI undergoing long-course neoadjuvant chemoradiation followed by proctectomy with curative intent between 1997 and 2007. Patients were stratified into pCR and no-pCR groups and compared with respect to demographics, tumor and treatment characteristics, and oncologic outcomes. Outcomes evaluated were 5-year overall survival, disease-free survival, disease-specific mortality, local recurrence, and distant recurrence.

RESULTS

The query returned 238 patients (73% male), with a median age of 57 years and median follow-up of 54 months. Of these, 58 patients achieved pCR. Patients with pCR vs no-pCR were statistically comparable with respect to demographics, chemoradiation regimens, tumor distance from anal verge, clinical stage, surgical procedures performed, and follow-up time. No patient with pCR had local recurrence. Overall survival and distant recurrence were also significantly improved for patients achieving pCR.

CONCLUSIONS

Achievement of pCR after neoadjuvant chemoradiation is associated with greatly improved cancer outcomes in locally advanced rectal cancer. Future studies should evaluate the relationship between increases in pCR rates and improvements in cancer outcomes in this population.

Complete clinical response after neoadjuvant chemoradiation therapy for distal rectal cancer: characterization of clinical and endoscopic findings for standardization

BACKGROUND

Complete tumor regression may develop after neoadjuvant chemoradiation therapy for distal rectal cancer. Studies have suggested that selected patients with complete clinical response may avoid radical surgery and close surveillance may provide good outcomes with no oncologic compromise. However, definition of complete clinical response is often imprecise and may vary between different studies. The aim of this study is to provide a clear definition for a complete clinical response after neoadjuvant chemoradiation therapy in patients with distal rectal cancer in addition to actual endoscopic videos from patients managed nonoperatively.

METHODS

Patients with nonmetastatic distal rectal cancer treated by neoadjuvant chemoradiation therapy, including 50.4 Gy and concomitant 5-fluorouracil and leucovorin, were assessed for tumor response at least 8 weeks after chemoradiation therapy completion. Complete and incomplete clinical responses were defined based on clinical and endoscopic findings. Patients with complete clinical response were not immediately operated on and were closely followed. Early and late endoscopic findings were recorded.

RESULTS

Definition of a complete clinical response should be based on very strict clinical and endoscopic criteria. The finding of any residual superficial ulceration, irregularity, or nodule should prompt surgical attention, including transanal full-thickness excision or even a radical resection with total mesorectal excision. Standard or incisional biopsies should be avoided in this setting. Complete clinical responders should harbor no more than whitening of the mucosa, teleangiectasia with mucosal integrity to be considered for a nonoperative approach. In the presence of these findings, regularly scheduled reassessments may provide a safe alternative to these patients with early detection of recurrent disease.

CONCLUSION

Strict definition of the clinical and endoscopic findings of patients experiencing complete clinical response after neoadjuvant chemoradiation therapy may provide a useful tool for the understanding of outcomes of patients managed with no immediate surgery allowing standardization of classifications and comparison between the experiences of different institutions.

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.

Laparoscopic versus open proctectomy for rectal cancer: patients' outcome and oncologic adequacy

BACKGROUND

The aim of this study was to compare laparoscopic management of rectal cancer to open surgery.

METHODS

The medical records of patients who underwent elective laparoscopic or open proctectomy for rectal cancer between November 2004 and July 2006 were retrospectively reviewed.

RESULTS

Thirty-two patients in the laparoscopic group (LG) were matched for tumor location, stage, comorbidity, and type of surgical procedure to 50 patients in the open group (OG). There were no statistically significant differences between the groups relative to American Society of Anesthesiologists score or tumor, node, metastasis stage; however, body mass index and age of the LG were significantly lower compared with the OG (P<0.05). In the LG, the procedure was successfully laparoscopically completed in 28 patients (87.5%). The median operative time was 240 minutes in the LG and 185 minutes in the OG (P< 0.05). Overall morbidity was 25% and 38%, respectively (P=0.1), the median hospital stay was 6 days, and median time to first bowel movement was 3 days in the LG compared with 7 and 4 days in the OG, respectively (P=0.7 and 0.01, respectively). The number of identified lymph nodes, distal and radial margins were comparable between both groups. Median follow-up was 10 (1 to 18) months.

CONCLUSIONS

Laparoscopic proctectomy for rectal cancer is feasible in 87.5% of patients and despite a longer operative time compared with laparotomy, is safe with the advantages of faster recovery of bowel function. This procedure does not compromise the oncologic adequacy of resection or significantly differ from open proctectomy relative to short-term outcomes.

Downstaging after chemoradiotherapy for locally advanced rectal cancer: is there more (tumor) than meets the eye?

PURPOSE

Preoperative chemoradiotherapy can lead to pathologic complete response of rectal cancer. This study was designed to determine the relationship between postchemoradiotherapy pathologic T stage (ypT stage) and nodal metastases and to evaluate whether pathologic complete response of the primary tumor results in sterilization of mesorectal lymph nodes.

METHODS

Clinicopathological data from 1997 to 2007 of a prospectively maintained colorectal cancer database were examined. Inclusion criteria were patients with extraperitoneal rectal cancer who underwent preoperative chemoradiotherapy and subsequent radical resection. Statistical analysis was performed by use of Kruskall-Wallis and Wilcoxon rank-sum tests.

RESULTS

Two hundred forty-two patients were identified (73.1% male, median age, 57 y (range, 36-85 y)). Data regarding preoperative chemoradiotherapy were available for 177 patients (73.1%). The median dose of radiotherapy was 5040 cGy (3060-6100 cGy). The mean preoperative radiotherapy dose and interval between chemoradiotherapy and surgery are similar when stratified by ypT stage (P = .55 and P = .72, respectively). Low anterior resection was performed in 174 patients (71.6%), and the remainder underwent abdominoperineal resection. A mural pathologic complete response was achieved in 62 patients (25.6%). In this pathologic complete-response group, positive lymph nodes were found in 2 patients (3.2%). The rate of metastatic lymph nodes increased as ypT stage increased (ypT1 = 11.1%, ypT2 = 29.2%, ypT3 = 37.3%).

CONCLUSION

Patients with a mural pathologic complete response have a low rate of positive lymph nodes. These findings may have implications for the management strategies of these patients, including the use of local resection or a watch-and-wait policy. When the response to chemoradiotherapy is not complete, radical surgery should remain the treatment based on high rates of lymph node involvement.

Complete pathologic response after preoperative rectal cancer chemoradiotherapy

BACKGROUND

Following preoperative treatment of rectal cancer with chemoradiotherapy (CRT), a complete pathological response (CPR) can be seen in the surgical specimen. The aim of this study was to assess the outcome of these patients as compared with those who did not have a complete response.

METHODS

A retrospective study of the outcome of patients managed with preoperative CRT for their rectal cancer was conducted.

RESULTS

Between November 1998 and July 2004, there were 530 new presentations of rectal cancer at The Queen Elizabeth and Royal Adelaide hospitals. Forty of these patients (7.5%) were treated with long-course preoperative CRT. After resection, a CPR was seen in seven patients (17.5%). These patients were all disease free at January 2006 after a median follow-up of 6.0 years (range 1.42-7.02 years). One patient had died from non-tumour-/surgery-related causes. Tumour recurrence, but not mortality, in this group was superior to the comparison group of patients without a CPR.

CONCLUSIONS

None of our patients who had a CPR after preoperative CRT have recurred or died from their disease.

Tumor volume changes assessed by three-dimensional magnetic resonance volumetry in rectal cancer patients after preoperative chemoradiation: the impact of the volume reduction ratio on the prediction of pathologic complete response

PURPOSE

The aim of this study was to determine the correlation between tumor volume changes assessed by three-dimensional (3D) magnetic resonance (MR) volumetry and the histopathologic tumor response in rectal cancer patients undergoing preoperative chemoradiation therapy (CRT).

METHODS AND MATERIALS

A total of 84 patients who underwent preoperative CRT followed by radical surgery were prospectively enrolled in the study. The post-treatment tumor volume and tumor volume reduction ratio (% decrease ratio), as shown by 3D MR volumetry, were compared with the histopathologic response, as shown by T and N downstaging and the tumor regression grade (TRG).

RESULTS

There were no significant differences in the post-treatment tumor volume and the volume reduction ratio shown by 3D MR volumetry with respect to T and N downstaging and the tumor regression grade. In a multivariate analysis, the tumor volume reduction ratio was not significantly associated with T and N downstaging. The volume reduction ratio (>75%, p = 0.01) and the pretreatment carcinoembryonic antigen level (< or =3 ng/ml, p = 0.01), but not the post-treatment volume shown by 3D MR (< or = 5 ml), were, however, significantly associated with an increased pathologic complete response rate.

CONCLUSION

More than 75% of the tumor volume reduction ratios were significantly associated with a high pathologic complete response rate. Therefore, limited treatment options such as local excision or simple observation might be considered after preoperative CRT in this patient population.

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.

The correlation between tumour regression grade and lymph node status after chemoradiation in rectal cancer

OBJECTIVE

To determine the correlation between tumour response to preoperative RCTX and lymph node status, an established parameter of clinical outcome.

METHOD

After IRB approval, 86 consecutive rectal cancer patients who received preoperative RCTX were identified. Fifty seven were males. Mean age 62 years. Preoperative staging by ultrasound was available in 60 patients. Radiotherapy consisted of (40-60 g) and chemotherapy of 5-FU infusion (1500 mg/m(2) week), assessed using Dworak's system.

RESULTS

Tumour response according to Tumor regression grade (TRG) were: TRG 0: 8 (9.3%); TRG 1: 15 (17.4%); TRG 2: 14 (16.2%); TRG 3: 31 (36%); TRG 4: 18 (20%). Eighteen patients had tumour stage 0 (20.9%); while 8 (9.2%), 28 (32.1%), 30 (34.5%) and three had tumours stages 1, 2, 3 and 4 respectively. Evaluation of nodal status revealed no involvement in 65 patients (N0), and positive nodes in 21 (14 N1, 7 N2). Response to RCTX was significantly associated with node stage, hence individuals without node involvement (N0) had 66% of positive tumour response (TRG 4), while individuals with node metastasis had less response to RCTX (TRG 0, 1 and 2) 35% N1 and 14% for N2 (P = 0.007). Node status was independently associated to poor response to preoperative RCTX, even after adjusting for tumour stage, age and gender (OR 0.02, 95% CI 0.0009-0.67).

CONCLUSION

Tumour shrinkage by preoperative RCTX appears to correlate with lymph node metastasis suggesting that neoadjuvant RCTX may have a positive impact in overall patient survival.

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.

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

PURPOSE

To assess the frequency and magnitude of changes in lower rectal cancer resulting from preoperative therapy and its impact on sphincter-saving surgery. Preoperative therapy can increase the rate of preserving surgery by shrinking the tumor and enhancing its distance from the anal sphincter. However, reliable data concerning these modifications are not yet available in published reports.

METHODS AND MATERIALS

A total of 98 cases of locally advanced cancer of the lower rectum (90 Stage uT3-T4N0-N+ and 8 uT2N+M0) that had undergone preoperative therapy were studied by endorectal ultrasonography. The maximal size of the tumor and its distance from the anal sphincter were measured in millimeters before and after preoperative therapy. Surgery was performed 6-8 weeks after therapy, and the histopathologic margins were compared with the endorectal ultrasound data.

RESULTS

Of the 90 cases, 82.5% showed tumor downsizing, varying from one-third to two-thirds or more of the original tumor mass. The distance between the tumor and the anal sphincter increased in 60.2% of cases. The median increase was 0.73 cm (range, 0.2-2.5). Downsizing was not always associated with an increase in distance. Preserving surgery was performed in 60.6% of cases. It was possible in nearly 30% of patients in whom the cancer had reached the anal sphincter before the preoperative therapy. The distal margin was tumor free in these cases.

CONCLUSION

The results of our study have shown that in very low rectal cancer, preoperative therapy causes tumor downsizing in >80% of cases and in more than one-half enhances the distance between the tumor and anal sphincter. These modifications affect the primary surgical options, facilitating or making sphincter-saving surgery possible.