Phase II study of capecitabine and oxaliplatin given prior to and concurrently with preoperative pelvic radiotherapy in patients with locally advanced rectal cancer. Br J Cancer. 2008;98:1204-1209. [PMID: 18349837 PMCID: PMC2359632 DOI: 10.1038/sj.bjc.6604297]

Population pharmacokinetic analyses of regorafenib and capecitabine in patients with locally advanced rectal cancer (SAKK 41/16 RECAP)

AIM

Locally advanced rectal cancer (LARC) is an area of unmet medical need with one third of patients dying from their disease. With response to neoadjuvant chemo-radiotherapy being a major prognostic factor, trial SAKK 41/16 assessed potential benefits of adding regorafenib to capecitabine-amplified neoadjuvant radiotherapy in LARC patients.

METHODS

Patients received regorafenib at three dose levels (40/80/120 mg once daily) combined with capecitabine 825 mg/m² bidaily and local radiotherapy. We developed population pharmacokinetic models from plasma concentrations of capecitabine and its metabolites 5'-deoxy-5-fluorocytidine and 5'-deoxy-5-fluorouridine as well as regorafenib and its metabolites M-2 and M-5 as implemented into SAKK 41/16 to assess potential drug-drug interactions (DDI). After establishing parent-metabolite base models, drug exposure parameters were tested as covariates within the respective models to investigate for potential DDI. Simulation analyses were conducted to quantify their impact.

RESULTS

Plasma concentrations of capecitabine, regorafenib and metabolites were characterized by one- and two compartment models and absorption was described by parallel first- and zero-order processes and transit compartments, respectively. Apparent capecitabine clearance was 286 L/h (relative standard error [RSE] 14.9%, interindividual variability [IIV] 40.1%) and was reduced by regorafenib cumulative area under the plasma-concentration curve (median reduction of 45.6%) as exponential covariate (estimate -4.10×10^-4 , RSE 17.8%). Apparent regorafenib clearance was 1.94 L/h (RSE 12.1%, IIV 38.1%). Simulation analyses revealed significantly negative associations between capecitabine clearance and regorafenib exposure.

CONCLUSIONS

This work informs the clinical development of regorafenib and capecitabine combination treatment and underlines the importance to study potential DDI with new anticancer drug combinations.

Efficacy and safety of sequential neoadjuvant chemotherapy and short-course radiation therapy followed by delayed surgery in locally advanced rectal cancer: a single-arm phase II clinical trial with subgroup analysis between the older and young patients

Purpose

This study was performed to investigate the efficacy and safety of short-course radiation therapy (SCRT) and sequential chemotherapy followed by delayed surgery in locally advancer rectal cancer with subgroup analysis between the older and young patients.

Materials and Methods

In this single-arm phase II clinical trial, eligible patients with locally advanced rectal cancer (T3–4 and/or N1–2) were enrolled. All the patients received a median three sequential cycles of neoadjuvant CAPEOX (capecitabine + oxaliplatin) chemotherapy. A total dose of 25 Gy in five fractions during 1 week was prescribed to the gross tumor and regional lymph nodes. Surgery was performed about 8 weeks following radiotherapy. Pathologic complete response rate (pCR) and grade 3–4 toxicity were compared between older patients (≥65 years) and younger patients (<65 years).

Results

Ninety-six patients with locally advanced rectal cancer were enrolled. There were 32 older patients and 64 younger patients. Overall pCR was 20.8% for all the patients. Older patients achieved similar pCR rate (18.7% vs. 21.8; p = 0.795) compared to younger patients. There was no statistically significance in terms of the tumor and the node downstaging or treatment-related toxicity between older patients and younger ones; however, the rate of sphincter-saving surgery was significantly more frequent in younger patients (73% vs. 53%; p=0.047) compared to older ones. All treatment-related toxicities were manageable and tolerable among older patients.

Conclusion

Neoadjuvant SCRT and sequential chemotherapy followed by delayed surgery was safe and effective in older patients compared to young patients with locally advanced rectal cancer.

Locally Advanced Rectal Cancer: What We Learned in the Last Two Decades and the Future Perspectives

The advancement in surgical techniques, optimization of systemic chemoradiotherapy, and development of refined diagnostic and imaging modalities have brought a phenomenal shift in the treatment of the locally advanced rectal cancer. Although each therapeutic option has shown substantial progress in their field, it is finding their ideal amalgamation which has baffled the clinician and researchers alike. In the effort to identifying the perfect salutary treatment plan, we have even shifted our attention from the trimodal approach to non-operative "watchful waiting" to more recent individualized care. In this article, we acknowledge the scientific progress in the management of locally advanced rectal cancer and compare the opportunities as well as the obstacles while implementing them clinically. We also explore the current challenges and controversies surrounding the multidisciplinary approach and highlight the new trends and recent advances with an ultimate goal to improve the patients' quality of life.

Current status of total neoadjuvant therapy for locally advanced rectal cancer

Neoadjuvant chemoradiotherapy (nCRT) plus total mesorectal excision (TME) has been the standard regimen for treatment of patients with locally advanced rectal cancer (LARC), because it significantly reduces the rate of local recurrence and enables sphincter preservation. However, distant metastasis remains the major reason for treatment failure, and the value of postoperative chemotherapy is still controversial. Recent studies have examined the use of total neoadjuvant therapy (TNT), defined as induction and/or consolidation chemotherapy (CONCT) with radiotherapy (RT) or nCRT prior to surgery. The results indicated that TNT may increase the rates of chemotherapy compliance and pathological complete response (pCR), and probably improve the success rate of sphincter preservation surgery. TNT may also improve disease-free survival and overall survival, and even reduce the rate of relapse. Here, we critically appraise the existing literature on three different TNT schemes used for LARC patients.

[Neoadjuvant treatment for rectal cancer]

The management of patients with locally advanced rectal cancer has improved significantly in the past few years with preoperative radiotherapy (RT) and total mesorectal excision. The rate of local recurrence is now around 5 % while the risk of metastatic recurrence has not been reduced which is about 30 %. The benefit of adjuvant chemotherapy remains questionable apart from patients with ypN+tumor after preoperative chemoradiotherapy (CRT) for whom FOLFOX is an option. In recent years, several therapeutic trials have evaluated the benefit of extending the time between the end of RT and surgery and/or the benefit of neoadjuvant chemotherapy, administered as induction (before RT) or in consolidation (after RT and before surgery). The first results of two positive phase 3 trials, PRODIGE 23 and RAPIDO, have been reported in 2020. The two regimens evaluated in these trials are markedly different but have shown that neoadjuvant chemotherapy significantly reduces the risk of distant metastasis. Current developments largely related to a de-escalation of therapy: organ conservation according to a "Watch and Wait" strategy or local resection of the scar, administration of neoadjuvant chemotherapy without RT. These therapeutic strategies have not yet been validated but should be in the news tomorrow. The purpose of this review is to present recent data reported in patients with locally advanced rectal cancer.

Predictive factors for early distant metastasis after neoadjuvant chemoradiotherapy in locally advanced rectal cancer

BACKGROUND

Distant relapse is the leading cause of cancer-related death in locally advanced rectal cancer. Neoadjuvant chemoradiation (NACRT) followed by surgery inevitably delays delivery of systemic treatment. Some patients show early distant metastasis before systemic treatment.

AIM

To identify the most effective treatments. We investigated prognostic factors for distant metastasis, especially early distant metastasis, using the standard treatment paradigm to identify the most effective treatments according to recurrence risk.

METHODS

From January 2015 through December 2019, rectal cancer patients who underwent NACRT for having clinical T 3-4 or clinical N 1-2 disease according to the 8^th American Joint Committee on Cancer staging system were included. Radiotherapy was delivered to the whole pelvis with concomitant chemotherapy. Patients received surgery 6-8 wk after completion of NACRT. Adjuvant chemotherapy was administered at the physician’s discretion.

RESULTS

A total of 127 patients received NACRT. Ninety-three patients (73.2%) underwent surgery. The R0 resection rate was 89.2% in all patients. Pathologic tumor and node downstaging rates were 41.9% and 76.3%. Half the patients (n = 69) received adjuvant chemotherapy after surgery. The 3-year distant metastasis-free survival (DMFS) and overall survival (OS) rates were 81.7% and 83.5%. On univariate analyses, poorly differentiated tumors, > 5 cm, involvement of mesorectal fascia (MRF), or presence of extramural involvement (EMVI) were associated with worse DMFS and OS. Five patients showed distant metastasis at their first evaluation after NACRT. Patients with early distant metastasis were more likely to have poorly differentiated tumor (P = 0.025), tumors with involved MRF (P = 0.002), and EMVI (P = 0.012) than those who did not.

CONCLUSION

EMVI, the involvement of MRF, and poor histologic grade were associated with early distant metastasis. In order to control distant metastasis and improve treatment outcome, selective use of neoadjuvant treatment according to individualized risk factors is necessary. Future studies are required to determine effective treatment strategies for patients at high risk for distant metastasis.

Adding Adjuvants to Fluoropyrimidine-based Neoadjuvant Chemoradiotherapy for Locally Advanced Rectal Cancer: An Option Worthy of Serious Consideration

The application of fluoropyrimidine-based neoadjuvant chemoradiotherapy (Fu-nCRT) of locally advanced rectal cancer (LARC) has become a common therapeutic regimen. In order to improve the efficacy and enable more patients to benefit from this treatment, an accumulation of studies have been carried out on the auxiliary use of other drugs with Fu-nCRT. However, due to specific challenges and the potential opportunities that coexist in this field, a more reasonable approach to the mode of treatment remains to be explored. In this review, we have summarized the results of the studies on the combination of Fu-nCRT with cytotoxic drugs, anti-tumor angiogenesis, and anti-EGFR agents, as well as the status of the application of immune checkpoint inhibitors in the neoadjuvant therapy of LARC patients.

Optimizing treatment sequencing of chemotherapy for patients with rectal cancer: The KIR randomized phase II trial

BACKGROUND

Randomized studies have shown low compliance to adjuvant chemotherapy in rectal cancer patients receiving preoperative chemotherapy and external beam radiation (CT/EBRT) with total mesorectal excision. We hypothesize that giving neoadjuvant CT before local treatment would improve CT compliance.

METHODS

Between 2010-2017, 180 patients were randomized (2:1) to either Arm A (AA) with FOLFOX x6 cycles prior to high dose rate brachytherapy (HDRBT) and surgery plus adjuvant FOLFOX x6 cycles, or Arm B (AB), with neoadjuvant HDRBT with surgery and adjuvant FOLFOX x12 cycles. The primary endpoint was CT compliance to ≥85% of full-dose CT for the first six cycles. Secondary endpoints were ypT0N0, five-year disease free survival (DFS), local control and overall survival (OS).

RESULTS

Patients were randomized to either AA (n = 120, median age (MA) 62 years) or AB (n = 60, MA 63 years). 175/180 patients completed HDRBT as planned (97.2%). In AA, two patients expired during CT; three patients post-randomization received short course EBRT because of progression under CT (n = 2, AA) or personal preference (n = 1, AB). ypT0N0 was 31% in AA and 28% in AB (p = 0.7). CT Compliance was 80% in AA and 53% in AB (p = 0.0002). Acute G3/G4 toxicity was 35.8% in AA and 27.6% in AB (p = 0.23). With a median follow-up of 48.5 months (IQR 33-72), the five-year DFS was 72.3% with AA and 68.3% with AB (p = 0.74), the five-year OS 83.8% for AA and 82.2% for AB (p = 0.53), and the five-year local recurrence was 6.3% for AA and 5.8% for AB (p = 0.71).

CONCLUSION

We confirmed improved compliance to neoadjuvant CT in this study. Although there is no statistical difference in ypT0N0 rate, local recurrence, and DFS between the two arms, a trend towards favourable oncological outcomes is observed.

Recent advances in (chemo-)radiation therapy for rectal cancer: a comprehensive review

The role of radiation therapy in the treatment of (colo)-rectal cancer has changed dramatically over the past decades. Introduced with the aim of reducing the high rates of local recurrences after conventional surgery, major developments in imaging, surgical technique, systemic therapy and radiation delivery have now created a much more complex environment leading to a more personalized approach. Functional aspects including reduction of acute or late treatment-related side effects, sphincter or even organ-preservation and the unsolved problem of still high distant failure rates have become more important while local recurrence rates can be kept low in the vast majority of patients. This review summarizes the actual role of radiation therapy in different subgroups of patients with rectal cancer, including the current standard approach in different subgroups as well as recent developments focusing on neoadjuvant treatment intensification and/or non-operative treatment approaches aiming at organ-preservation.

Immune-Modulating Effects of Conventional Therapies in Colorectal Cancer

Biological heterogeneity and low inherent immunogenicity are two features that greatly impact therapeutic management and outcome in colorectal cancer. Despite high local control rates, systemic tumor dissemination remains the main cause of treatment failure and stresses the need for new developments in combined-modality approaches. While the role of adaptive immune responses in a small subgroup of colorectal tumors with inherent immunogenicity is indisputable, the challenge remains in identifying the optimal synergy between conventional treatment modalities and immune therapy for the majority of the less immunogenic cases. In this context, cytotoxic agents such as radiation and certain chemotherapeutics can be utilized to enhance the immunogenicity of an otherwise immunologically silent disease and enable responsiveness to immune therapy. In this review, we explore the immunological characteristics of colorectal cancer, the effects that standard-of-care treatments have on the immune system, and the opportunities arising from combining immune checkpoint-blocking therapy with immune-modulating conventional treatments.

Survival Benefit for Metformin Through Better Tumor Response by Neoadjuvant Concurrent Chemoradiotherapy in Rectal Cancer

BACKGROUND

Metformin may reduce cancer risk and mortality and improve radiotherapy responses in several malignancies.

OBJECTIVE

This study aimed to compare tumor responses and prognoses of metformin and nonmetformin groups of diabetic patients receiving neoadjuvant concurrent chemoradiotherapy for rectal cancer.

DESIGN

This is a retrospective study.

SETTING

This study was conducted at a single institution in the Republic of Korea.

PATIENTS

Between January 2000 and November 2017, 104 patients with rectal cancer who were taking diabetes medication and treated with neoadjuvant concurrent chemoradiotherapy followed by radical surgery were reviewed. Patients were divided into those taking (n = 62) and not taking metformin (n = 42). Tumor responses, survival, and other outcomes were analyzed.

MAIN OUTCOME MEASURES

Tumor response, rectal cancer-specific survival, and disease-free survival rates were measured.

RESULTS

Tumor regression grade (p = 0.002), pathological complete response (p = 0.037), and N downstaging (p < 0.001) after neoadjuvant concurrent chemoradiotherapy were significantly higher in the metformin group than in the nonmetformin group. In analysis of cancer-specific mortality, metformin use, differentiation (well, moderate vs poor), pathological Union for International Cancer Control stage (3 vs 1-2), ypN stage (1-2 vs 0), and N downstaging (HR, 0.256 (95% CI, 0.082-0.794), p = 0.018; HR, 0.147 (95% CI, 0.031-0.697), p = 0.016; HR, 3.693 (95% CI, 1.283-10.635), p = 0.015; HR, 3.181 (95% CI, 1.155-8.759), p = 0.025, and HR, 0.175 (95% CI, 0.040-0.769), p = 0.021) were significant factors related to mortality in diabetic patients with rectal cancer. In addition, in the multivariate analysis of cancer recurrence, the interaction between metformin use and lymph node downstaging was a significant predictive factor (HR, 0.222 (95% CI, 0.077-0.639); p = 0.005).

LIMITATIONS

This was a small retrospective study conducted at a single institution.

CONCLUSIONS

Metformin use was associated with better tumor responses and cancer-specific survival, as well as a lower risk of cancer recurrence, in patients with diabetes mellitus who had lymph node downstaging after neoadjuvant concurrent chemoradiotherapy in rectal cancer. See Video Abstract at http://links.lww.com/DCR/B185. BENEFICIO EN SUPERVIVENCIA CON METFORMINA A TRAVÉS DE UNA MEJOR RESPUESTA TUMORAL CON QUIMIORRADIOTERAPIA CONCURRENTE NEOADYUVANTE EN CÁNCER RECTAL: La metformina puede reducir el riesgo de cáncer y la mortalidad y mejorar las respuestas a la radioterapia en varios tumores malignos.Comparar las respuestas tumorales y los pronósticos de los grupos con metformina y sin metformina de pacientes diabéticos que reciben quimiorradioterapia concurrente neoadyuvante para cáncer de recto.Estudio retrospectivo.Institución única en la República de Corea.Se revisaron 104 pacientes entre enero de 2000 y noviembre de 2017, con cáncer rectal que tomaban medicamentos para diabetes y que fueron tratados con quimiorradioterapia concurrente neoadyuvante seguida de cirugía radical. Los pacientes se dividieron en aquellos que tomaban (n = 62) y los que no tomaban metformina (n = 42). Se analizaron las respuestas tumorales, la supervivencia y otros resultados.Se midieron las tasas de la respuesta tumoral, la supervivencia específica de cáncer rectal y de la supervivencia libre de enfermedad.El grado de regresión tumoral (p = 0.002), la remisión patológica completa (p = 0.037) y la reducción de la etapa N (p < 0.001) después de la quimiorradioterapia concurrente neoadyuvante fueron significativamente mayores en el grupo de metformina que en el grupo sin metformina. En el análisis de la mortalidad específica por cáncer, el uso de metformina, la diferenciación (bien, moderada vs pobre), el estadio patológico UICC (3 vs 1-2), el estadio ypN (1-2 vs 0) y la disminución de la etapa N (hazard ratios [intervalos de confianza 95%]: 0.256 [0.082-0.794], p = 0.018; 0.147 [0.031-0.697], p = 0.016; 3.693 [1.283-10.635], p = 0.015; 3.181 [1.155-8.759], p = 0.025 y 0.175 [0.040-0.769], p = 0.021, respectivamente) fueron factores significativos relacionados con la mortalidad en pacientes diabéticos con cáncer rectal. Adicionalmente, en el análisis multivariado de la recurrencia del cáncer, la interacción entre el uso de metformina y la disminución de la etapa ganglionar (N) fue un factor predictivo significativo (hazard ratios [intervalos de confianza del 95%]: 0.222 [0.077-0.639]; p = 0.005).Este fue un estudio retrospectivo pequeño realizado en un solo instituto.El uso de metformina se asoció con mejores respuestas tumorales y supervivencia específica de cáncer, así como un menor riesgo de recurrencia del cáncer, en pacientes con disminución de la etapa ganglionar (N) después de quimiorradioterapia concurrente neoadyuvante en pacientes con cáncer rectal y diabetes. Consulte Video Resumen en http://links.lww.com/DCR/B185. (Traducción-Dr. Jorge Silva Velazco).

Immunogenic cell death by neoadjuvant oxaliplatin and radiation protects against metastatic failure in high-risk rectal cancer

OBJECTIVE

High rates of systemic failure in locally advanced rectal cancer call for a rational use of conventional therapies to foster tumor-defeating immunity.

METHODS

We analyzed the high-mobility group box-1 (HMGB1) protein, a measure of immunogenic cell death (ICD), in plasma sampled from 50 patients at the time of diagnosis and following 4 weeks of induction chemotherapy and 5 weeks of sequential chemoradiotherapy, both neoadjuvant modalities containing oxaliplatin. The patients had the residual tumor resected and were followed for long-term outcome.

RESULTS

Patients who met the main study end point-freedom from distant recurrence-showed a significant rise in HMGB1 during the induction chemotherapy and consolidation over the chemoradiotherapy. The higher the ICD increase, the lower was the metastatic failure risk (hazard ratio 0.26, 95% confidence interval 0.11-0.62, P = 0.002). However, patients who received the full-planned oxaliplatin dose of the chemoradiotherapy regimen had poorer metastasis-free survival (P = 0.020) than those who had the oxaliplatin dose reduced to avert breach of the radiation delivery, which is critical to maintain efficient tumor cell kill and in the present case, probably also protected the ongoing radiation-dependent ICD response from systemic oxaliplatin toxicity.

CONCLUSION

The findings indicated that full-dose induction oxaliplatin followed by an adapted oxaliplatin dose that was compliant with full-intensity radiation caused induction and maintenance of ICD and as a result, durable disease-free outcome for a patient population prone to metastatic progression.

Efficacy and Feasibility of Adding Induction Chemotherapy to Neoadjuvant Chemoradiation in Locally Advanced Rectal Cancer: A Phase II Clinical Trial

Purpose

Currently, neoadjuvant chemoradiation (CRT) followed by total mesorectal resection is considered the standard of care for treating locally advanced rectal cancer. This study aimed to investigate the efficacy and feasibility of adding induction chemotherapy to neoadjuvant CRT in locally advanced rectal cancer.

Methods

This phase-II clinical trial included 54 patients with newly diagnosed, locally advanced (clinical T3–4 and/or N1–2, M0) rectal cancer. All patients were treated with 3 cycles of preoperative chemotherapy using the XELOX (capecitabine + oxaliplatin) regimen before and after a concurrent standard long course of CRT (45–50.4 Gy) followed by standard radical surgery. Pathologic complete response (PCR) rate and toxicity were the primary and secondary endpoints, respectively.

Results

The study participants included 37 males and 17 females, with a median age of 59 years (range, 20–80 years). Twenty-nine patients (54%) had clinical stage-II disease, and 25 patients (46%) had clinical stage-III disease. Larger tumor size (P = 0.006) and distal rectal location (P = 0.009) showed lower PCR compared to smaller tumor size and upper rectal location. Pathologic examinations showed significant tumor regression (6.1 ± 2.7 cm vs. 1.9 ± 1.8 cm, P < 0.001) with 10 PCRs (18.5%) compared to before the intervention. The surgical margin was free of cancer in 52 patients (96.3%). Treatment-related toxicities were easily tolerated, and all patients completed their planned treatment without interruption. Grade III and IV toxicities were infrequent.

Conclusion

The addition of induction chemotherapy to neoadjuvant CRT is an effective and well-tolerated treatment approach in patients with rectal cancer.

Prospective clinical study of capecitabine plus oxaliplatin concurrent chemoradiotherapy after radical resection of rectal cancer

BACKGROUND

To investigate the efficacy and safety of concurrent chemoradiotherapy with capecitabine or oxaliplatin in locally advanced (T3-4/N + M0) rectal cancer.

METHODS

56 patients with rectal cancer after radical operation were randomly divided into CAPE-OX-CRT group: capecitabine + oxaliplatin concurrent chemoradiotherapy (30 cases), CAPE-CRT group: capecitabine concurrent chemoradiotherapy (control, 26 cases).

RESULTS

The incidence of grade 1-2 acute toxicity in CAPE-OX-CRT group during concurrent CRT was significantly higher than that in control group, the difference was statistically significant (P < 0.05). Grade 3 toxicities were not statistically significant between the two groups (P > 0.05). No grade 4 toxicity was found in both groups. The incidences of interrupted or suspend concurrent chemotherapy in both groups were 19.23% and 46.67%, respectively, P < 0.05. The incidences of interruption or suspension of radiotherapy were 11.54% and 30% respectively (P > 0.05). The completion rate of adjuvant chemotherapy in control group was higher than that in CAPE-OX-CRT group, but the difference was not statistically significant (P > 0.05). In postoperative adjuvant chemotherapy, the incidence of bone marrow suppression in CAPE-OX-CRT group was higher than that in control group (P < 0.05), and the incidence of non-hematologic adverse reactions was similar between the two groups.

CONCLUSION

Capecitabine combined oxaliplatin concurrent CRT, and oxaliplatin concurrent CRT have a good effect for treatment of patients with locally advanced rectal cancer after radical resection of rectal cancer.

Systemic immune response induced by oxaliplatin-based neoadjuvant therapy favours survival without metastatic progression in high-risk rectal cancer

Background

Systemic failure remains a challenge in rectal cancer. We investigated the possible systemic anti-tumour immune activity invoked within oxaliplatin-based neoadjuvant therapy.

Methods

In two high-risk patient cohorts, we assessed the circulating levels of the fms-like tyrosine kinase 3 ligand (Flt3L), a factor reflecting both therapy-induced myelosuppression and activation of tumour antigen-presenting dendritic cells, at baseline and following induction chemotherapy and sequential chemoradiotherapy, both modalities containing oxaliplatin. The primary end point was progression-free survival (PFS).

Results

In both cohorts, the median Flt3L level was significantly higher at completion of each sequential modality than at baseline. The 5-year PFS (most events being metastatic progression) was 68% and 71% in the two cohorts consisting of 33% and 52% T4 cases. In the principal cohort, a high Flt3L level following the induction chemotherapy was associated with low risk for a PFS event (HR: 0.15; P < 0.01). These patients also had available dose scheduling and toxicity data, revealing that oxaliplatin dose reduction during chemoradiotherapy, undertaken to maintain compliance to the radiotherapy protocol, was associated with advantageous PFS (HR: 0.47; P = 0.046).

Conclusion

In high-risk rectal cancer, oxaliplatin-containing neoadjuvant therapy may promote an immune response that favours survival without metastatic progression.

Pilot Study of Intense Neoadjuvant Chemoradiotherapy for Locally Advanced Rectal Cancer: Retrospective Review of a Phase II Study

Aims and Background

Locally advanced rectal adenocarcinoma is typically treated with neoadjuvant chemoradiotherapy and surgery. We assessed the effect of an additional cycle of capecitabine/oxaliplatin chemotherapy before surgery in 57 patients with T3/4, N+/- or T1/2, N+ rectal cancer.

Materials and Study Design

Radiotherapy (total dose, 50.4 Gy) was combined with three cycles of chemotherapy (two cycles concomitant with radiotherapy), and each cycle consisted of oxaliplatin (130 mg/m2 on day 1) and capecitabine (825 mg/m2, twice per day from day 1 to day 14) for 21 days. In addition to assessing the safety of this treatment, the primary endpoint was pathological complete response (pCR). The secondary endpoint was the change in primary tumor and node stage from pre-treatment to post-surgery.

Results

Eleven patients (19%) experienced complete tumor regression and 23 patients (40%) experienced tumor regression grade 3. Tumor down-staging occurred in 31 patients (54.4%) and down-staging of nodes occurred in 25 patients (43.9%). There was a significant difference in tumor stage between pre-treatment and post-surgery (P <0.001). Patients with less advanced N stages had significantly better recurrence-free survival but similar metastasis-free survival and overall survival. Tumor regression grade was not associated with overall survival, recurrence-free survival or metastasis-free survival. The most common adverse events were pulmonary infection (n = 6, 10.5%) and intestinal obstruction (n = 6, 10.5%).

Conclusions

An additional cycle of chemotherapy given after chemoradiotherapy and before surgery provided good efficacy and had a satisfactory safety profile in patients with locally advanced rectal cancer.

Contemporary management of locally advanced rectal cancer: Resolving issues, controversies and shifting paradigms

Advancements in rectal cancer treatment have resulted in improvement only in locoregional control and have failed to address distant relapse, which is the predominant mode of treatment failure in rectal cancer. As the efficacy of conventional chemoradiotherapy (CRT) followed by total mesorectal excision (TME) reaches a plateau, the need for alternative strategies in locally advanced rectal cancer (LARC) has grown in relevance. Several novel strategies have been conceptualized to address this issue, including: 1) neoadjuvant induction and consolidation chemotherapy before CRT; 2) neoadjuvant chemotherapy alone to avoid the sequelae of radiation; and 3) nonoperative management for patients who achieved pathological or clinical complete response after CRT. This article explores the issues, recent advances and paradigm shifts in the management of LARC and emphasizes the need for a personalized treatment plan for each patient based on tumor stage, location, gene expression and quality of life.

Addition of oxaliplatin to capecitabine-based preoperative chemoradiotherapy for locally advanced rectal cancer: Long-term outcome of a phase II study

Our previous study reported the favorable short-term outcome and good tolerance of integrating oxaliplatin into capecitabine-based (XELOX regimen) preoperative chemoradiotherapy (CRT) for locally advanced rectal cancer (LARC). The present study reported the long-term oncological outcome of this phase II study. A total of 47 patients with rectal adenocarcinoma (stage II or III) were enrolled and received radiotherapy (46 Gy in 23 fractions) in combination with capecitabine (1,000 mg/m², twice daily, on days 1–14 and 22–35) and oxaliplatin (130 mg/m² on days 1 and 22). Overall survival (OS) rate, disease-free survival (DFS) rate and cumulative incidence of recurrences and long-term complications were calculated or observed. As a result, 41 patients underwent surgery after preoperative CRT, and the cumulative OS rates at 1, 3 and 5 years for these patients were 100.0, 84.5 and 81.8%, respectively. For the 38 patients who received R0 resection, the cumulative OS rates at 1, 3 and 5 years were 100.0, 89.0 and 86.2%, respectively, while the cumulative DFS rates at 1, 3 and 5 years were 94.6, 75.3 and 69.7%, respectively. After follow-up at 84 months, the cumulative incidence rates of local and distant recurrences at 5 years were 6.6 and 28.2%, respectively. Oxaliplatin-associated long-term complications were seldom observed. Overall, the addition of oxaliplatin to capecitabine-based preoperative radiotherapy achieved favorable OS and DFS without increased long-term complications in patients with LARC. Therefore, this preoperative CRT strategy is a feasible option for such patients.

Phase 2 Neoadjuvant Treatment Intensification Trials in Rectal Cancer: A Systematic Review

PURPOSE

Multiple phase 2 trials of neoadjuvant treatment intensification in locally advanced rectal cancer have reported promising efficacy signals, but these have not translated into improved cancer outcomes in phase 3 trials. Improvements in phase 2 trial design are needed to reduce these false-positive signals. This systematic review evaluated the design of phase 2 trials of neoadjuvant long-course radiation or chemoradiation therapy treatment intensification in locally advanced rectal cancer.

METHODS AND MATERIALS

The PubMed, EMBASE, MEDLINE, and Cochrane Library databases were searched for published phase 2 trials of neoadjuvant treatment intensification from 2004 to 2016. Trial clinical design and outcomes were assessed, with statistical design and compliance rated using a previously published system. Multivariable meta-regression analysis of pathologic complete response (pCR) was conducted.

RESULTS

We identified 92 eligible trials. Patients with American Joint Committee on Cancer stage II and III equivalent disease were eligible in 87 trials (94.6%). In 43 trials (46.7%), local staging on magnetic resonance imaging was mandated. Only 12 trials (13.0%) were randomized, with 8 having a standard-treatment control arm. Just 51 trials (55.4%) described their statistical design, with 21 trials (22.8%) failing to report their sample size derivation. Most trials (n=84, 91.3%) defined a primary endpoint, but 15 different primary endpoints were used. All trials reported pCR rates. Only 38 trials (41.3%) adequately reported trial statistical design and compliance. Meta-analysis revealed a pooled pCR rate of 17.5% (95% confidence interval, 15.7%-19.4%) across treatment arms of neoadjuvant long-course radiation or chemoradiation therapy treatment intensification and substantial heterogeneity among the reported effect sizes (I² = 55.3%, P<.001). Multivariable meta-regression analysis suggested increased pCR rates with higher radiation therapy doses (adjusted P=.025).

CONCLUSIONS

Improvement in the design of future phase 2 rectal cancer trials is urgently required. A significant increase in randomized trials is essential to overcome selection bias and determine novel schedules suitable for phase 3 testing. This systematic review provides key recommendations to guide future treatment intensification trial design in rectal cancer.

Total neoadjuvant therapy for rectal cancer: An emerging option

The treatment of locally advanced rectal cancer (LARC) has benefited from improved surgical techniques and from the implementation of neoadjuvant chemoradiotherapy (CRT), which have markedly decreased the rates of local recurrence. However, distant metastatic disease remains the most significant cause of death for these patients. Although adjuvant chemotherapy (ChT) after neoadjuvant CRT and definitive surgery is commonly recommended, the value of adjuvant systemic therapy remains less clear. Trials evaluating adjuvant ChT for rectal cancer have been handicapped by poor compliance rates and inconsistent survival results. Shifting systemic therapy delivery to the neoadjuvant setting has the promise to improve compliance rates, reduce toxicity, and decrease distant relapse rates. Recently, multiple prospective trials have reported on the use of total neoadjuvant therapy (TNT) for patients with LARC, incorporating both ChT and CRT in the neoadjuvant setting. Here, the authors review the promising results from those trials. Because the studies have largely focused on pathologic outcomes (primarily pathologic complete response rates), ongoing phase 2 and 3 trials are now underway assessing the long-term disease-related outcomes with TNT. In addition to improving survival, TNT has the potential to increase the pool of patients with LARC who are eligible for organ preservation, which is also being evaluated. Cancer 2017;123:1497-1506. © 2017 American Cancer Society.

Clinical factors of post-chemoradiotherapy as valuable indicators for pathological complete response in locally advanced rectal cancer

OBJECTIVES

Pathological complete response has shown a better prognosis for patients with locally advanced rectal cancer after preoperative chemoradiotherapy. However, correlations between post-chemoradiotherapy clinical factors and pathologic complete response are not well confirmed. The aim of the current study was to identify post-chemoradiotherapy clinical factors that could serve as indicators of pathologic complete response in locally advanced rectal cancer.

METHODS

This study retrospectively analyzed 544 consecutive patients with locally advanced rectal cancer treated at Sun Yat-sen University Cancer Center from December 2003 to June 2014. All patients received preoperative chemoradiotherapy followed by surgery. Univariate and multivariate regression analyses were performed to identify post-chemoradiotherapy clinical factors that are significant indicators of pathologic complete response.

RESULTS

In this study, 126 of 544 patients (23.2%) achieved pathological complete response. In multivariate analyses, increased pathological complete response rate was significantly associated with the following factors: post-chemoradiotherapy clinical T stage 0-2 (odds ratio=2.098, 95% confidence interval=1.023-4.304, p=0.043), post-chemoradiotherapy clinical N stage 0 (odds ratio=2.011, 95% confidence interval=1.264-3.201, p=0.003), interval from completion of preoperative chemoradiotherapy to surgery of >7 weeks (odds ratio=1.795, 95% confidence interval=1.151-2.801, p=0.010) and post-chemoradiotherapy carcinoembryonic antigen ≤2 ng/ml (odds ratio=1.579, 95% confidence interval=1.026-2.432, p=0.038).

CONCLUSIONS

Post-chemoradiotherapy clinical T stage 0-2, post-chemoradiotherapy clinical N stage 0, interval from completion of chemoradiotherapy to surgery of >7 weeks and post-chemoradiotherapy carcinoembryonic antigen ≤2 ng/ml were independent clinical indicators for pathological complete response. These findings demonstrate that post-chemoradiotherapy clinical factors could be valuable for post-operative assessment of pathological complete response.

Oxaliplatin-containing Preoperative Therapy in Locally Advanced Rectal Cancer: Local Response, Toxicity and Long-term Outcome

AIMS

This non-randomised study was undertaken to examine oxaliplatin as possibly an intensifying component of sequential neoadjuvant therapy in locally advanced rectal cancer for improved local and metastatic outcome.

MATERIALS AND METHODS

Ninety-seven patients (57 T2-3 cases, 40 T4 cases) received two cycles of the Nordic FLOX regimen (oxaliplatin 85 mg/m(2) day 1 and bolus 5-fluorouracil 500 mg/m(2) and folinic acid 100 mg days 1 and 2) before long-course chemoradiotherapy with concomitant oxaliplatin and capecitabine, followed by pelvic surgery. Treatment toxicity, local tumour response and long-term outcome were recorded.

RESULTS

Good histologic tumour regression was obtained in 72% of patients. Implementing protocol-specific dose adjustments, tolerance was acceptable and 95% of patients received the total prescribed radiation dose. Estimated 5 year progression-free and overall survival were 61% and 83%, respectively. T4 stage was associated with an inferior local response rate, which again was highly associated with impaired long-term outcome.

CONCLUSIONS

In this cohort of rectal cancer patients dominated by T4 and advanced T3 cases given sequential oxaliplatin-containing preoperative therapy with acceptable toxicity, high tumour response rates and overall survival were obtained, consistent with both local and systemic effects. However, tumour response and long-term outcome remained inferior for a significant number of T4 cases, suggesting that the T4 entity is biologically heterogeneous with subgroups of patients eligible for further individualisation of therapy.

Timing of Therapies in the Multidisciplinary Treatment of Locally Advanced Rectal Cancer: Available Evidence and Implications for Routine Practice

A multimodality disciplinary approach is paramount for the management of locally advanced rectal cancer. Over the last decade, (chemo)radiotherapy followed by surgery plus or minus adjuvant chemotherapy has represented the mainstay of treatment for this disease. Nevertheless, robust evidence suggesting the optimal timing and sequence of therapies in this setting has been overall limited. A number of questions are still unsolved including the length of the interval between neoadjuvant radiotherapy and surgery or the timing of systemic chemotherapy. Interestingly, emerging data support the contention that altering sequence or timing or both of the components of this multimodality approach may provide an opportunity to implement treatment strategies that far better address the risk and expectations of individual patients. In this article, we review the available evidence on timing of therapies in the multidisciplinary treatment of locally advanced rectal cancer and discuss the potential implications for routine practice that may derive from a change of the currently accepted treatment paradigm.

Early increase in circulating carbonic anhydrase IX during neoadjuvant treatment predicts favourable outcome in locally advanced rectal cancer

Background

Locally advanced rectal cancer (LARC) comprises heterogeneous tumours with predominant hypoxic components. The hypoxia-inducible metabolic shift causes microenvironmental acidification generated by carbonic anhydrase IX (CAIX) and facilitates metastatic progression, the dominant cause of failure in LARC.

Methods

Using a commercially available immunoassay, circulating CAIX was assessed in prospectively archived serial serum samples collected during combined-modality neoadjuvant treatment of LARC patients and correlated to histologic tumour response and progression-free survival (PFS).

Results

Patients who from their individual baseline level displayed serum CAIX increase above a threshold of 224 pg/ml (with 96 % specificity and 39 % sensitivity) after completion of short-course neoadjuvant chemotherapy (NACT) prior to long-course chemoradiotherapy and definitive surgery had significantly better 5-year PFS (94 %) than patients with below-threshold post-NACT versus baseline alteration (PFS rate of 56 %; p < 0.01). This particular CAIX parameter, ΔNACT, was significantly correlated with histologic ypT0–2 and ypN0 outcome (p < 0.01) and remained an independent PFS predictor in multivariate analysis wherein it was entered as continuous variable (p = 0.04).

Conclusions

Our results indicate that low ΔNACT, i.e., a weak increase in serum CAIX level following initial neoadjuvant treatment (in this case two cycles of the Nordic FLOX regimen), might be used as risk-adapted stratification to postoperative therapy or other modes of intensification of the combined-modality protocol in LARC.

Trial registration

ClinicalTrials.gov NCT00278694

Electronic supplementary material

The online version of this article (doi:10.1186/s12885-015-1557-6) contains supplementary material, which is available to authorized users.

Short- and Long-Term Quality of Life and Bowel Function in Patients With MRI-Defined, High-Risk, Locally Advanced Rectal Cancer Treated With an Intensified Neoadjuvant Strategy in the Randomized Phase 2 EXPERT-C Trial

OBJECTIVE

Intensified preoperative treatments have been increasingly investigated in locally advanced rectal cancer (LARC), but limited data are available for the impact of these regimens on quality of life (QoL) and bowel function (BF). We assessed these outcome measures in EXPERT-C, a randomized phase 2 trial of neoadjuvant capecitabine combined with oxaliplatin (CAPOX), followed by chemoradiation therapy (CRT), total mesorectal excision, and adjuvant CAPOX with or without cetuximab in magnetic resonance imaging-defined, high-risk LARC.

METHODS AND MATERIALS

QoL was assessed using the European Organization for Research and Treatment of Cancer QLQ-C30 and QLQ-CR29 questionnaires. Bowel incontinence was assessed using the modified Fecal Incontinence Severity Index questionnaire.

RESULTS

Compared to baseline, QoL scores during preoperative treatment were better for symptoms associated with the primary tumor in the rectum (blood and mucus in stool, constipation, diarrhea, stool frequency, buttock pain) but worse for global health status, role functioning, and symptoms related to the specific safety profile of each treatment modality. During follow-up, improved emotional functioning and lessened anxiety and insomnia were observed, but deterioration of body image, increased urinary incontinence, less sexual interest (men), and increased impotence and dyspareunia were observed. Cetuximab was associated with a deterioration of global health status during neoadjuvant chemotherapy but did not have any long-term detrimental effect. An improvement in bowel continence was observed after preoperative treatment and 3 years after sphincter-sparing surgery.

CONCLUSIONS

Intensifying neoadjuvant treatment by administering induction systemic chemotherapy before chemoradiation therapy improves tumor-related symptoms and does not appear to have a significantly detrimental effect on QoL and BF, in both the short and the long term.

The emerging role of neoadjuvant chemotherapy for rectal cancer

Locally advanced rectal cancer remains a substantial public health problem. Historically, the disease has been plagued by high rates of both distant and local recurrences. The standardization of pre-operative chemoradiation and transmesorectal excision (TME) have greatly lowered the rates of local recurrence. Efforts to improve treatment through use of more effective radiosensitizing therapies have proven unsuccessful in rectal cancer. Presently, due to improved local therapies, distal recurrences represent the dominant problem in this disease. Adjuvant chemotherapy is currently of established benefit in colorectal cancer. As such, adjuvant chemotherapy, consisting of fluoropyrimidine and oxaliplatin, represent the standard of care for many patients. However, after pre-operative chemoradiotherapy and rectal surgery, the administration of highly effective chemotherapy regimens has proven difficult. For this reason, novel neoadjuvant approaches represent appealing avenues for investigation. Strategies of neoadjuvant chemotherapy alone, neoadjuvant chemotherapy followed by chemoradiation and neoadjuvant chemoradiation followed by chemotherapy are under investigation. Initial encouraging results have been noted, though definitive phase III data is lacking.

Neoadjuvant chemoradiation therapy using concurrent S-1 and irinotecan in rectal cancer: impact on long-term clinical outcomes and prognostic factors

PURPOSE

To assess the long-term outcomes of patients with rectal cancer who received neoadjuvant chemoradiation therapy (NCRT) with concurrent S-1 and irinotecan (S-1/irinotecan) therapy.

METHODS AND MATERIALS

The study group consisted of 115 patients with clinical stage T3 or T4 rectal cancer. Patients received pelvic radiation therapy (45 Gy) plus concurrent oral S-1/irinotecan. The median follow-up was 60 months.

RESULTS

Grade 3 adverse effects occurred in 7 patients (6%), and the completion rate of NCRT was 87%. All 115 patients (100%) were able to undergo R0 surgical resection. Twenty-eight patients (24%) had a pathological complete response (ypCR). At 60 months, the local recurrence-free survival was 93%, disease-free survival (DFS) was 79%, and overall survival (OS) was 80%. On multivariate analysis with a proportional hazards model, ypN2 was the only independent prognostic factor for DFS (P=.0019) and OS (P=.0064) in the study group as a whole. Multivariate analysis was additionally performed for the subgroup of 106 patients with ypN0/1 disease, who had a DFS rate of 85.3%. Both ypT (P=.0065) and tumor location (P=.003) were independent predictors of DFS. A combination of these factors was very strongly related to high risk of recurrence (P<.0001), which occurred most commonly in the lung.

CONCLUSIONS

NCRT with concurrent S-1/irinotecan produced high response rates and excellent long-term survival, with acceptable adverse effects in patients with rectal cancer. ypN2 is a strong predictor of dismal outcomes, and a combination of ypT and tumor location can identify high-risk patients among those with ypN0/1 disease.

A complete response to mFOLFOX6 and panitumumab chemotherapy in advanced stage rectal adenocarcinoma: a case report

BACKGROUND

Pathological complete remission of advanced stage rectal adenocarcinoma by chemotherapy alone is rare. A case of advanced stage, low-lying rectal adenocarcinoma in which a complete response to treatment was obtained with mFOLFOX6 and panitumumab (Pmab) is reported.

CASE PRESENTATION

A 53-year-old man was referred to Shiga University of Medical Science hospital Shiga, Japan, complaining of bloody stool. Gastrointestinal endoscopy was performed, and advanced stage rectal adenocarcinoma was diagnosed. Computed tomography (CT) revealed regional lymph node metastases in the mesorectum. Neoadjuvant chemotherapy (NAC) with mFOLFOX6 and Pmab was planned.Endoscopy following four courses of chemotherapy revealed that the rectal cancer had been markedly reduced, and the results of biopsies of the rectal tumor were negative for cancer. On CT, the mesorectal lymph node metastases had disappeared. Total intersphincteric resection (ISR) with a handsewn coloanal anastomosis was performed. Histological examination showed a complete response to mFOLFOX6 and Pmab in advanced stage rectal cancer.

CONCLUSION

The result seen in this case suggests that short-term NAC with mFOLFOX6 and Pmab was effective for low-lying rectal adenocarcinoma.

Prognosis of rectal cancer patients improves with downstaging by intensified neoadjuvant radiochemotherapy - a matched pair analysis

Background

Neoadjuvant radiochemotherapy has been proven superior to adjuvant treatment in reducing the rate of local recurrence without impairing cancer related survival or the incidence of distant metastases in standard protocols of neoadjuvant radiochemotherapy. The present study aimed at addressing the effects of an intensified neoadjuvant radiochemotherapy on long term cancer related and disease free survival.

Methods

A total of 387 patients underwent oncologic resection for rectal cancer in our institution between January 2000 and December 2009. There were 106 patients (27.4%) who received an intensified radiochemotherapy protocol completely and without excluding criteria (study group). A matched pair analysis was performed by comparing the study group with patients undergoing primary surgery and postoperative radiochemotherapy, if necessary and possible (control group). Matching was carried out in descending order for UICC stage, R-status, tumor height, T-, N-, V-, L-, M- and G-category of the TNM-system according to the histopathological staging. Follow-up data included local recurrence rate, cancer related and disease free survival.

Results

In the study group histopathological work-up of the specimen revealed a treatment response in terms of tumor regression in 92.5% (98/106) of these patients. Undergoing intensified neoadjuvant RCT the actuarial cancer related and disease free survival was 67.9% and 70.4%, local recurrence was 5.7% after an observation period of 4.3 ± 2.55 years. In the control group cancer related and disease free survival was 71.7% and 82.7%, local recurrence was 4.7% after an observation period of 3.8 ± 3.05 years revealing no statistical significant difference between the two groups. Moreover, estimated 5-year results of cancer related survival (66.7% vs 67.9% (controls)), the disease free survival (66.7% vs 79.9% (controls)) as well as subgroup analysis of UICC 0-III and UICC IV patients showed no difference between the study and control group as well.

Conclusion

In our study, intensified neoadjuvant radio-chemotherapy shows a high rate of tumor regression. The resulting inferior histopathological tumor stage shows the same long term local control and systemic tumor control as the control group with a primary more favorable tumor stage.

Long-term results with oral fluoropyrimidines and oxaliplatin-based preoperative chemoradiotherapy in patients with resectable rectal cancer. A single-institution experience

INTRODUCTION

Neoadjuvant 5-FU-based chemoradiotherapy in resectable rectal cancer (RC) is a standard of treatment. The use of oral fluoropyrimidines and new agents such as oxaliplatin may improve efficacy and tolerance.

MATERIAL AND METHODS

Between 1999 and 2009, 126 RC patients with T3-T4 and/or N+ disease were given three successive protocols: UFT (32), UFT-oxaliplatin (75) and capecitabine-oxaliplatin (19), alongside 45 Gy of radiotherapy; with surgery 4-6 weeks after. Adjuvant treatment was given in all patients. The primary objective was pathologic complete response (pCR).

RESULTS

Preoperative therapy was well tolerated, with no toxic deaths and a 15% grade 3-4 toxicity rate. Eighty-five percent of patients received the full chemotherapy dose, 56% had an abdominoperineal resection, 6% reinterventions and 57% received the full adjuvant chemotherapy planned. The pCR rate was 13%. The downstaging rate was 80%; 8% had progression of disease. The relapse rate was 20%, with local relapse in 6%. By 5 years of followup, 92% of relapses had occurred. Median follow-up was 73 months, 5- and 10-year disease-free survival rates were 75% and 50%, and 5- and 10-year overall survival rates were 79% and 66% respectively. There was no benefit from the use of oxaliplatin regarding survival or pCR rates. Older patients had worse long-term outcomes.

CONCLUSIONS

Neoadjuvant chemoradiotherapy with oral fluoropyrimidines and oxaliplatin is feasible and well tolerated. The risk of early progression is low. However, there was no added benefit with the use of oxaliplatin. There were no relapses in patients with pCR. The role of adjuvant chemotherapy is unclear.

Prospective phase II trial of neoadjuvant chemo-radiotherapy with Oxaliplatin and Capecitabine in locally advanced rectal cancer (XELOXART)

Neo-adjuvant chemo-radiotherapy (CT-RT) has been shown to decrease local recurrence rate in locally advanced rectal cancer. This multicenter phase II trial was conducted to evaluate the feasibility, safety and effectiveness of a combination of pre-operative radiotherapy and concurrent Capecitabine plus Oxaliplatin (XELOXART Trial). From October 2008 to May 2011, fifty consecutive patients affected with T3/T4 and/or N+ rectal cancer were enrolled. Treatment protocol consisted of 50.4 Gy in 28 fractions, Oxaliplatin 60 mg/m(2) once a week for 6 weeks and oral Capecitabine 825 mg/m(2) twice daily from day 1 to 14 and from day 22 to 35. Surgery was planned 6-8 weeks after. Main endpoints were pathological complete response rate (pCR) and the type of surgery performed compared to the planned one at diagnosis. 50 patients were included; pCR (ypT0N0M0) was achieved in 6 patients (12 %). Tumour downstaging was observed in 27 patients (54 %), and nodal downstaging in 32 patients (64 %). A total of 32 patients had lower rectal cancer, with 24 candidate for abdominal-perineal resection. At the end of CT-RT, a total of 12/24 (50 %) underwent conservative surgery. Grade 3 toxicity (fatigue and diarrhoea) occurred in 4 % of patients; grade 4 sensory neuropathy occurred in 2 % of patients. Perioperative complications of any grade occurred in 10 % of patients. Pre-operative CT-RT with Capecitabine-Oxaliplatin was well tolerated and resulted in an encouraging sphincter preservation and tumour downstaging rate. No improvements in terms of pathological complete response rate were shown.

Mortality risk after preoperative versus postoperative chemotherapy and radiotherapy in lymph node-positive rectal cancer

INTRODUCTION

Persistent lymph node-positive disease after preoperative radiotherapy for rectal cancer is associated with adverse outcomes. We quantified mortality risks of persistent pathologic lymph nodes in lymph node-positive rectal cancer patients treated with preoperative versus postoperative chemoradiation.

METHODS

This was a retrospective population-based analysis of 2,038 patients with stage III rectal cancer diagnosed 1994-2005 with follow-up through 2007 using data from the California Cancer Registry. Survival estimates were generated using the Kaplan-Meier method. Multivariate cancer-specific and overall mortality analyses were performed using Cox proportional hazard ratios with adjustment for age, gender, race/ethnicity, tumor grade, T stage, N stage, socioeconomic status, and time period (1994-1997, 1998-2001, and 2002-2005).

RESULTS

Overall survival was higher among lymph node-positive patients receiving postoperative chemoradiation compared to lymph node-positive patients receiving preoperative chemoradiation (median overall survival = 87 versus 62 months, P = 0.0002). In adjusted analyses, patients with persistent lymph node-positive disease after preoperative chemoradiation treatment had increased overall (HR = 1.69; 95 % CI, 1.42-2.01) and CRC-specific (HR = 1.78; 95 % CI, 1.44-2.19) mortality risk compared to lymph node-positive disease after postoperative chemoradiation treatment.

CONCLUSIONS

Stage III rectal cancer patients with persistent pathologic lymph nodes after preoperative chemoradiation represent a high-risk group, with higher mortality than those treated with postoperative chemoradiation.

Effect of neoadjuvant cetuximab, capecitabine, and radiotherapy for locally advanced rectal cancer: results of a phase II study

PURPOSE

The aim of this study was to investigate the efficacy and safety of neoadjuvant cetuximab, capecitabine, and radiotherapy for patients with locally advanced rectal cancer.

METHODS

Sixty-three eligible patients were selectively enrolled in this study. Neoadjuvant treatment consisted of cetuximab and capecitabine for 6 weeks and radiotherapy for 5 weeks. Surgical resection was performed 6-8 weeks after the completion of neoadjuvant treatment. KRAS mutation statuses were analyzed retrospectively after the cetuximab treatment. All the patients underwent a standardized postoperative follow-up for at least 3 years.

RESULTS

A pathological complete response (pCR) was achieved in eight patients (12.7 %). Overall down-staging was found in 49 patients (77.8 %). The 3-year disease-free survival (DFS) rate and overall survival (OS) rate was 76.2 % and 81.0 %, respectively. The most common adverse events during neoadjuvant treatment were acneiform skin rash (82.5 %), radiodermatitis (46.0 %), and diarrhea (36.5 %). KRAS mutations were detected in 19 of 63 (31.2 %) tumors. The down-staging rate in patients with KRAS wild-type (WT) was significantly higher than patients with KRAS mutation (P = 0.020). There was no significant difference in the pCR rate, 3-year DFS rate or 3-year OS rate between KRAS WT patients and KRAS-mutated patients.

CONCLUSION

Neoadjuvant treatment with cetuximab and capecitabine-based chemoradiotherapy is safe and well tolerated. The pCR rate, 3-year DFS rate and OS rate are not superior to the rate of neoadjuvant chemoradiotherapy using two or more cytotoxic agents. The KRAS WT is highly associated with tumor down-staging to cetuximab plus capecitabine-based CRT in patients with LARC.

The role of capecitabine in locally advanced rectal cancer treatment: an update

Preoperative infusional 5-fluorouracil (5-FU) and concurrent radiation therapy (RT) followed by total mesorectal surgery is the current standard of care for locally advanced rectal cancer (LAR). When compared with postoperative 5-FU-based chemoradiation, this strategy is associated with significantly lower rates of local relapse, lower toxicity and better compliance. Capecitabine is a rationally designed oral prodrug that is converted into 5-FU by intracellular thymidine phosphorylase. Substitution of infusional 5-FU with capecitabine is an attractive option that provides a more convenient administration schedule and, possibly, increased efficacy. Indeed, incorporation of capecitabine in combined modality neoadjuvant therapy for LAR has been under intense investigation during the last 10 years. Phase I and II clinical trials showed that a regimen consisting of capecitabine 825mg/m(2) twice daily for 7 days/week continuous oral administration in combination with RT is an active and well tolerated regimen, thereby being the preferred concurrent regimen. The definitive demonstration that efficacy of capecitabine/RT is similar to 5-FU/RT has been provided by the NSABP-R-04 and the German Margit trials. One approach to improve outcomes in rectal cancer is to deliver a second RT-sensitizing drug with effective systemic activity. Oxaliplatin and irinotecan are therefore good candidates. However, two phase III trials demonstrated that incorporation of oxaliplatin to capecitabine with RT did not improve early outcomes and, by contrast, increased toxicity. Capecitabine has also been combined with irinotecan. This regimen showed encouraging results in phase I and II clinical trials, which led to an ongoing phase III clinical trial. New strategies with induction chemotherapy with or without chemoradiation prior to surgery are currently under investigation. Whether or not capecitabine has a role in this setting is being investigated in ongoing trials. Incorporation of agents directed towards new targets, such as anti-epidermal growth factor receptor (EGFR) antibodies or antiangiogenic agents, in combination preoperative regimens, is being hampered by results of early trials in which efficacy outcomes with cetuximab were poor and an excessive rate of surgical complications with bevacizumab was observed. The lack of improvements in efficacy with the addition of cetuximab or bevacizumab in the adjuvant treatment of colon cancer led to concerns about further development of these agents in rectal cancer. The role of capecitabine in the postoperative adjuvant setting is the aim of the ongoing Dutch SCRIPT trial. The prediction of response associated with capecitabine has been based on expression of thymidylate synthase and dihydropyrimidine dehydrogenase, as well as on gene expression arrays. All these procedures require further validation and should be considered as investigational. In conclusion, capecitabine can safely and effectively replace intravenous continuous infusion of 5-FU in the preoperative chemoradiation setting for rectal cancer management. The addition of other new antineoplastic agents to a fluoropyrimidine-based regimen remains investigational.

Current status of intensified neo-adjuvant systemic therapy in locally advanced rectal cancer

The addition of 5-fluorouracil (5-FU) or its prodrug capecitabine to radiotherapy (RT) is a standard approach in the neo-adjuvant treatment of patients with rectal tumors extending beyond the muscularis propria (stage II) and/or with clinical evidence of regional lymph node metastases (stage III). According to European randomized trials, the combined treatment modality resulted in favorable local control rates as compared with radiotherapy (RT) alone, but no improvement was found regarding the occurrence of distant metastases or overall survival. In an effort to further enhance the response rates and to decrease the high incidence of distant metastases in locally advanced rectal cancer patients, the addition of other chemotherapeutical drugs and biologic agents as radiation sensitizers to neo-adjuvant 5-FU based chemoradiotherapy (CRT) has been recently investigated. The role of those agents is however questionable as first results from phase III data do not show improvement on pathologic complete remission and circumferential resection margin negative resection rates as compared to 5-FU based CRT, nevertheless an increased toxicity.

Simultaneous neoadjuvant radiochemotherapy with capecitabine and oxaliplatin for locally advanced rectal cancer. Treatment outcome outside clinical trials

BACKGROUND

Phase II trials of neoadjuvant treatment in UICC-TNM stage II and III rectal cancer with capecitabine and oxaliplatin demonstrated favourable rates on tumour regression with acceptable toxicity.

PATIENTS AND METHODS

Retrospective evaluation of 34 patients treated from 2005-2008 outside clinical trials (CTR) with neoadjuvant irradiation (45-50.4 Gy) and simultaneous capecitabine 825 mg/m(2) b.i.d. on days 1-14 and 22-35 and oxaliplatin 50 mg/m(2) on days 1, 8, 22 and 29 (CAPOX). Twenty-six (77%) patients received one or two courses of capecitabine 1,000 mg/m(2) b.i.d. on days 1-14 and oxaliplatin 130 mg/m(2) on day 1 (XELOX) prior to simultaneous chemoradiotherapy.

RESULTS

UICC-TNM stage regression was observed in 60% (n = 20). Dworak's regression grades 3 and 4 were achieved in 18.2% (n = 6) and 15.1% (n = 5) of the patients. Sphincter-preserving surgery was performed in 53% (n = 8) of patients with a tumour of the lower rectum. Within the mean observation of 24 months, none of the patients relapsed locally, 1 patient had progressive disease and 5 patients (15%) relapsed distantly. Toxicity of grade 3 and 4 was mainly diarrhoea 18% (n = 6) and perianal pain 9% (n = 3). Nevertheless, severe cardiac events (n = 2), severe electrolyte disturbances (n = 2), and syncopes (n = 2) were observed as well.

CONCLUSION

Treatment efficacy and common toxicity are similar to the reports of phase I/II trials. However, several severe adverse events were observed in our cohort study. The predisposing factors for these events have yet to be studied and may have implications for the selection of patients outside CTR.

Neoadjuvant chemotherapy in MRI-staged high-risk rectal cancer in addition to or as an alternative to preoperative chemoradiation?

BACKGROUND

For patients with resectable rectal cancer chemoradiation (CRT) or short-course preoperative radiotherapy (SCPRT) reduces locoregional failure, without extending disease-free survival (DFS) or overall survival (OS). Compliance to postoperative adjuvant chemotherapy is poor. Neoadjuvant chemotherapy (NACT) offers an alternative strategy.

METHODS

A systematic computerised database search identified studies exploring NACT alone or NACT preceding/succeeding radiation. The primary outcome measure was pathological complete response (pCR). Secondary outcome measures included acute toxicity, surgical morbidity, circumferential resection margin, locoregional failure, DFS and OS.

RESULTS

Four case reports, 12 phase I/II studies, 4 randomised phase II and one randomised phase III study evaluated chemotherapy before CRT. Four prospective studies reviewed chemotherapy after CRT. Three phase II studies investigated chemotherapy using FOLFOX plus bevacizumab without radiotherapy. In 24 studies of 1271 patients, pCR varied from 7% to 36%, but with no impact on metastatic disease.

CONCLUSIONS

NACT before CRT delivers does not compromise CRT but has not increased pCR rates, R0 resection rate, improved DFS or reduced metastases. NACT following CRT is an interesting strategy, and the utility of NACT alone could be explored compared with SCPRT or CRT in selected patients with rectal cancer where the impact of radiotherapy on DFS and OS is marginal.

Oxaliplatin as a radiosensitiser for upper and lower gastrointestinal tract malignancies: what have we learned from a decade of translational research?

Some of the greatest advances in the treatment of solid malignancies have resulted from the combination of chemotherapy and radiotherapy treatments. This article comprehensively reviews the current clinical evidence for oxaliplatin-based chemo-radiotherapy that may improve local control and survival. In order to understand how clinical studies should be designed, the pre-clinical evidence for the use of oxaliplatin chemotherapy as a radiosensitising agent is appraised. Particular focus is placed on oxaliplatin's biological mechanisms of action, including cell cycle effects, the formation of DNA adducts and interstrand cross-links and the role of DNA repair proteins. At a clinical level, there is currently no evidence to suggest that oxaliplatin provides an additional benefit to concurrent chemo-radiation regimes that utilise fluoropyrimidines; we evaluate the reasons for this observation, the limitations of clinical trial design and the opportunities that currently exist to design clinical trials which are underpinned by an understanding of the basic biology.

Four-week neoadjuvant intensity-modulated radiation therapy with concurrent capecitabine and oxaliplatin in locally advanced rectal cancer patients: a validation phase II trial

PURPOSE

To validate tolerance and pathological complete response rate (pCR) of a 4-week preoperative course of intensity-modulated radiation therapy (IMRT) with concurrent capecitabine and oxaliplatin (CAPOX) in patients with locally advanced rectal cancer.

METHODS AND MATERIALS

Patients with T3 to T4 and/or N+ rectal cancer received preoperative IMRT (47.5 Gy in 19 fractions) with concurrent capecitabine (825 mg/m(2) b.i.d., Monday to Friday) and oxaliplatin (60 mg/m(2) on Days 1, 8, and 15). Surgery was scheduled 4 to 6 weeks after the completion of chemoradiation. Primary end points were toxicity and pathological response rate. Local control (LC), disease-free survival (DFS), and overall survival (OS) were also analyzed.

RESULTS

A total of 100 patients were evaluated. Grade 1 to 2 proctitis was observed in 73 patients (73%). Grade 3 diarrhea occurred in 9% of the patients. Grade 3 proctitis in 18% of the first 50 patients led to reduction of the dose per fraction to 47.5 Gy in 20 treatments. The rate of Grade 3 proctitis decreased to 4% thereafter (odds ratio, 0.27). A total of 99 patients underwent surgery. A pCR was observed in 13% of the patients, major response (96-100% of histological response) in 48%, and pN downstaging in 78%. An R0 resection was performed in 97% of the patients. After a median follow-up of 55 months, the LC, DFS, and OS rates were 100%, 84%, and 87%, respectively.

CONCLUSIONS

Preoperative CAPOX-IMRT therapy (47.5 Gy in 20 fractions) is feasible and safe, and produces major pathological responses in approximately 50% of patients.

A phase II study of oxaliplatin with 5-FU/folinic acid and concomitant radiotherapy as a preoperative treatment in patients with locally advanced rectal cancer

OBJECTIVE

To evaluate the activity and safety of adding oxaliplatin to a standard chemoradiotherapy schema, including 5-fluorouracil (5-FU)/folinic acid (FA), in locally-advanced rectal cancer (LARC).

METHODS

Two cycles of oxaliplatin 130 mg/m(2) plus FA 20 mg/m(2) bolus for 5 days and 5-FU 350 mg/m(2) continuous infusion for 5 days were given during week 1 and 4 of pelvic radiotherapy 46 Gy. Patients with a T3/4 and/or node-positive rectal tumour were eligible. Surgery was performed 4-6 weeks after radiotherapy. The primary endpoint was to determine the rate of pathological response. Secondary endpoints were to assess the rate of clinical response and the safety profile.

RESULTS

Between March 2005 and January 2009, a total of 35 patients were enrolled. The pathological down-staging rate was 79% with a pathological complete response rate of 17%. The overall clinical response rate (assessed by computed tomography or transrectal ultrasound) was 77%. Grade 3 diarrhoea and Grade 3 neutropaenia were reported in 14% and 11% of the patients, respectively. Eleven patients did not undergo surgery: four of them refused the operation, and seven patients were inoperable due to disease progression. In 24 patients who had surgery, a sphincter-preserving procedure could be performed in 29%. At the median follow-up time of 28.1 months, 25 patients (71%) survived with no evidence of disease.

CONCLUSION

The promising results in terms of pathological response, and the associated good safety profile of a regimen of oxaliplatin plus 5-FU/FA with concomitant radiotherapy, suggest that the regimen could be used in LARC.