Postoperative chemotherapy may not be necessary for patients with ypN0-category after neoadjuvant chemoradiotherapy of rectal cancer

The clinical relevance of adjuvant chemotherapy in locally advanced rectal cancer patients achieving near pathological complete response following neoadjuvant chemoradiotherapy: Insights from ypT stage

BACKGROUND

Near-pathological complete response (Near-pCR) patients constitute a distinct subgroup with limited research attention. The clinical relevance of adjuvant chemotherapy (ACT) in this patient cohort remains uncertain.

METHODS

We conducted a retrospective analysis of 245 patients with locally advanced rectal cancer (LARC) who achieved near-pCR following neoadjuvant chemoradiotherapy (NCRT) between 2011 and 2018. Based on their receipt of ACT or not (non-ACT), patients were divided into two groups. We examined their characteristics, treatment modalities, and survival outcomes, particularly focusing on 5-year disease-free survival (DFS) and 5-year overall survival (OS).

RESULTS

Among the 245 near-pCR patients, 191 (77.96%) received ACT, and 42 (17.14%) experienced disease recurrence. All 54 (22.04%) Patients in the non-ACT group exhibited a lower 5-year DFS rate (72.2% vs. 85.9%, P = 0.014) and a similar 5-year OS rate (87.0% vs. 91.1%, P = 0.351). Interestingly, those with ypT3-T4 stage tumors demonstrated a worse DFS (76.8% vs. 89.9%, P = 0.010) and OS (87.5% vs. 97.0%, P = 0.004) compared to their counterparts with ypT1-T2 stage tumors. Patients with Non-Downstage tumors showed inferior DFS (76.9% vs. 88.3%, P = 0.025) and OS (87.2% vs. 93.0%, P = 0.166) in comparison to patients with Downstage tumors. The ACT subgroup in patients with Downstage demonstrated statistically better 5-year DFS (93.0% vs. 71.4%, P = 0.001) but analogous survival rates for 5-year OS (OS: 94.0% vs. 89.3%, P = 0.402). Pathological T stage 3-4, perineural invasion (PNI) (positive) and ACT were independent factors influencing 5-year DFS in multivariate analysis. Both univariate and multivariate analysis demonstrated a link between serum carcinoembryonic antigen (CEA) before treatment ≥5 ng/ml and shorter 5-year OS. Notably, near-pCR patients with positive lymph nodes experienced notably diminished 5-year DFS in the absence of ACT post-surgery (61.1% vs. 93.2%, P < 0.001).

CONCLUSIONS

ACT demonstrated a significant positive impact on the prognosis of select near-pCR patients, particularly those with ypT1-T2 stage tumors and positive lymph nodes. ypT staging may emerge as a valuable criterion for precise post-surgical ACT guidance in near-pCR patients.

Neoadjuvant Chemoradiotherapy Does Not Contribute to Worse Survival in Pathological Node-Negative Rectal Cancer

Purpose: The prognostic significance of ypN0 rectal cancer with comparison to pN0 disease still remains poorly defined. This study aimed to compare the prognosis of ypN0 and pN0 rectal cancer.

Methods: Eligible patients were identified from the SEER18 registries research database (the latest data up to date was on April 15, 2019). Propensity score (PS) matching was usually performed to reduce the imbalance and potential confounding that were introduced by inherent differences between the groups. The cause-specific survival (CSS) was analyzed to evaluate the prognostic prediction of ypN0 and pN0 groups using the Kaplan–Meier method with the log-rank test. Cox proportional hazard model was also used to identify independent prognostic variables.

Results: In total, 26,832 patients diagnosed with pN0 or ypN0 rectal cancer were confirmed as the final cohort, including 7,237 (27.0%) patients with radiation and 19,595 (73.0%) patients without radiation prior to surgery. The median follow-up time was up to 81 months. After adjusting for other prognostic factors, neoadjuvant radiotherapy was not an independent prognostic variable of CSS (HR = 1.100, 95%CI = 0.957–1.265, P = 0.180, using pN0 group as the reference).

Conclusions: ypN0 rectal cancer was strongly associated with worse pathological diagnoses compared with pN0 rectal cancer, contributing to worse oncologic outcomes. However, the receipt of neoadjuvant chemoradiotherapy was not an independent prognostic factor of worse prognosis in pathological node-negative patients. Our study could give guidance to the treatment of ypN0 rectal cancer.

Risk Stratification Using Neoadjuvant Rectal Score in the Era of Neoadjuvant Chemoradiotherapy: Validation With Long-term Outcome Data

BACKGROUND

Despite the widespread use of neoadjuvant chemoradiotherapy, there is no prognostic surrogate marker established in locally advanced rectal cancer.

OBJECTIVE

This study evaluated the role of neoadjuvant rectal score as a prognostic factor to stratify individual-level risks of survival and tumor recurrence.

DESIGN

This is a retrospective study.

SETTINGS

This study was conducted at the Seoul National University Hospital.

PATIENTS

A total of 397 patients who underwent chemoradiotherapy plus total mesorectal excision were analyzed.

INTERVENTIONS

There was no intervention.

MAIN OUTCOME MEASURES

Harrell C statistic and receiver operating characteristic analysis, as well as Cox regression analysis, were used to assess the prognostic strength.

RESULTS

The low (<8), intermediate (8-16), and high (>16) neoadjuvant rectal score groups included 91 (23%), 208 (52%), and 98 patients (25%). A high neoadjuvant rectal score was independently associated with inferior overall survival and disease-free survival (p = 0.011 and 0.008). Regarding the prognostic models adjusted for neoadjuvant rectal score (I) and ypT/N stage (II), the c-index was higher in model I (0.799 and 0.787, p = 0.009 for overall survival; 0.752 and 0.743, p = 0.093 for disease-free survival). The predictive ability of the neoadjuvant rectal score was superior to tumor regression grade, ypT, and ypN in the receiver operating characteristic analyses (p < 0.05 for all). Adjuvant chemotherapy was associated with better overall and disease-free survival (p = 0.003 and 0.052) in the high neoadjuvant rectal score group.

LIMITATIONS

Potential selection bias attributed to the retrospective study design was a limitation.

CONCLUSIONS

We verified the applicability of the neoadjuvant rectal score to stratify the relapse risk at the individual level for patients with stage II/III rectal cancer undergoing neoadjuvant chemoradiotherapy. Additional studies are needed to validate the usability of neoadjuvant rectal score levels as a determinant of adjuvant strategy. See Video Abstract at http://links.lww.com/DCR/B354. ESTRATIFICACIÓN DE RIESGO UTILIZANDO LA PUNTUACIÓN RECTAL NEOADYUVANTE EN LA ERA DE LA QUIMIORRADIOTERAPIA NEOADYUVANTE: VALIDACIÓN CON DATOS DE RESULTADOS A LARGO PLAZO: A pesar del uso generalizado de la quimiorradioterapia neoadyuvante, no existe un marcador subrogado pronóstico establecido en el cáncer de recto localmente avanzado.Este estudio evaluó el papel de la puntuación rectal neoadyuvante como factor pronóstico para estratificar los riesgos a nivel individual de supervivencia y recurrencia tumoral.Este es un estudio retrospectivo.Este estudio se realizó en el Hospital de la Universidad Nacional de Seúl.Se analizaron un total de 397 pacientes que se sometieron a quimiorradioterapia más escisión mesorrectal total.No hubo intervención.El análisis estadístico C de Harrell y las características operativas del receptor, así como el análisis de regresión de Cox, se utilizaron para evaluar la fuerza pronóstica.Los grupos de puntaje rectal neoadyuvante bajo (<8), intermedio (8-16) y alto (> 16) incluyeron 91 (23%), 208 (52%) y 98 (25%) pacientes, respectivamente. Una puntuación rectal neoadyuvante alta se asoció independientemente con una supervivencia general y una supervivencia libre de enfermedad inferiores (p = 0.011 y 0.008, respectivamente). Con respecto a los modelos pronósticos ajustados por la puntuación rectal neoadyuvante (I) y el estadio ypT/N (II), el índice c fue mayor en el modelo I (0.799 y 0.787, p = 0.009 para la supervivencia general; 0.752 y 0.743, p = 0.093 para supervivencia libre de enfermedad). La capacidad predictiva de la puntuación rectal neoadyuvante fue superior al grado de regresión tumoral, ypT y ypN en los análisis de características operativas del receptor (p <0.05 para todos). La quimioterapia adyuvante se asoció con una mejor supervivencia global y libre de enfermedad (p = 0.003 y 0.052, respectivamente) en el grupo de puntaje rectal neoadyuvante alto.El sesgo de selección potencial debido al diseño retrospectivo del estudio fue la limitación.Verificamos la aplicabilidad de la puntuación rectal neoadyuvante para estratificar el riesgo de recurrencia a nivel individual para pacientes con cáncer rectal en estadio II/III sometidos a quimiorradioterapia neoadyuvante. Se necesitan más estudios para validar la usabilidad de los niveles de puntuación rectal neoadyuvante como determinante de la estrategia adyuvante. Consulte Video Resumen en http://links.lww.com/DCR/B354.

Staging of Locally Advanced Rectal Cancer Beyond TME

The management of rectal cancer is complex and continually evolving. With advancements in technology and the use of multidisciplinary teams to guide the treatment decision making, staging, oncologic, and functional outcomes are improving, and the management is moving toward personalized treatment strategies to optimize each individual patient's outcomes. Key in this evolution is imaging. Magnetic resonance imaging (MRI) has emerged as the dominant method of pelvic imaging in rectal cancer, and use of MRI for staging is best practice in multiple international guidelines. MRI allows a noninvasive assessment of the tumor site, relationship to surrounding structures, and provides highly accurate rectal cancer staging, which is necessary for determining the appropriate treatment strategy. However, the applications of MRI extend far beyond pretreatment staging. MRI can be used to predict outcomes in locally advanced rectal cancer and guide the surgical or nonsurgical plan, serving as a predictive and prognostic biomarker. With continued MRI hardware improvement and new sequence development, MRI may offer new perspectives in the assessment of treatment response and new innovations that could provide better insight into the staging, restaging, and outcomes with rectal cancer.

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).

Impact of Adjuvant Chemotherapy Completion on Oncologic Outcomes in ypTNMstage 2 Rectal Cancer Patients

PURPOSE

Adjuvant chemotherapy (aCT) in rectal cancer patients who have undergone curative resection after neoadjuvant chemoradiation (nCRT) is controversial. We aimed to investigate the benefits of using aCT and the clinical impact of completing aCT in ypstage 2 rectal cancer patients.

METHODS

We retrospectively reviewed clinicopathological data from patients who had undergone radical resection after nCRT between January 2006 and December 2012. In total, 152 patients with ypT3/4N0M0 rectal cancer were included. Of these patients, 139 initiated aCT, while 13 did not receive aCT (no-aCT). Among those who received aCT, 132 patients completed their planned cycles (aCT-completion) whereas 7 did not (aCT-incompletion). All patients received longcourse chemoradiation; a 5-fluorouracil-based regimen was used for nCRT in most patients. The prognostic factors affecting disease-free survival (DFS) and overall survival (OS) were analyzed.

RESULTS

The median follow-up duration was 41 months. Demographic data did not differ significantly among the 3 groups. In multivariate analysis, open surgery, a tumor size >2 cm, retrieval of <12 lymph nodes, circumferential resection margin (CRM) positivity and aCT incompletion were independent prognostic factors for poor DFS. Old age (≥60 years), open surgery, CRM positivity, aCT incompletion, and lack of aCT initiation compared to aCT completion were independent prognostic factors for poor OS.

CONCLUSION

In ypstage 2 rectal cancer patients, aCT after nCRT and total mesorectal excision affected both DFS and OS; however, only patients who completed planned aCT exhibited survival benefits. Therefore, improving patients' compliance with the completion of aCT is desirable.

Association Between Adjuvant Chemotherapy and Overall Survival in Patients With Rectal Cancer and Pathological Complete Response After Neoadjuvant Chemotherapy and Resection

Importance

Although American guidelines recommend use of adjuvant chemotherapy in patients with locally advanced rectal cancer, individuals who achieve a pathological complete response (pCR) following neoadjuvant chemoradiotherapy are less likely to receive adjuvant treatment than incomplete responders. The association and resection of adjuvant chemotherapy with survival in patients with pCR is unclear.

Objective

To determine whether patients with locally advanced rectal cancer who achieve pCR after neoadjuvant chemoradiation therapy and resection benefit from the administration of adjuvant chemotherapy.

Design, Setting, and Participants

This retrospective propensity score-matched cohort study identified patients with locally advanced rectal cancer from the National Cancer Database from 2006 through 2012. We selected patients with nonmetastatic invasive rectal cancer who achieved pCR after neoadjuvant chemoradiation therapy and resection.

Exposures

We matched patients who received adjuvant chemotherapy to patients who did not receive adjuvant treatment in a 1:1 ratio. We separately matched subgroups of patients with node-positive disease before treatment and node-negative disease before treatment to investigate for effect modification by pretreatment nodal status.

Main Outcome and Measures

We compared overall survival between groups using Kaplan-Meier survival methods and Cox proportional hazards models.

Results

We identified 2455 patients (mean age, 59.5 years; 59.8% men) with rectal cancer with pCR after neoadjuvant chemoradiation therapy and resection. We matched 667 patients with pCR who received adjuvant chemotherapy and at least 8 weeks of follow-up after surgery to patients with pCR who did not receive adjuvant treatment. Over a median follow-up of 3.1 years (interquartile range, 1.94-4.40 years), patients treated with adjuvant chemotherapy demonstrated better overall survival than those who did not receive adjuvant treatment (hazard ratio, 0.44; 95% CI, 0.28-0.70). When stratified by pretreatment nodal status, only those patients with pretreatment node-positive disease exhibited improved overall survival with administration of adjuvant chemotherapy (hazard ratio, 0.24; 95% CI, 0.10-0.58).

Conclusions and Relevance

The administration of adjuvant chemotherapy in patients with rectal cancer with pCR is associated with improved overall survival, particularly in patients with pretreatment node-positive disease. Although this study suggests a beneficial effect of adjuvant treatment on survival in patients with pCR, these results are limited by the presence of potential unmeasured confounding in this nonrandomized study.

Adjuvant Chemotherapy Improves Survival Following Resection of Locally Advanced Rectal Cancer with Pathologic Complete Response

BACKGROUND

Controversy exists over the use of adjuvant chemotherapy for locally advanced (stages II-III) rectal cancer (LARC) patients who demonstrate pathologic complete response (pCR) following neoadjuvant chemoradiation. We conducted a retrospective analysis to determine whether adjuvant chemotherapy imparts survival benefit among this population.

METHODS

The National Cancer Database (NCDB) was queried to identify LARC patients with pCR following neoadjuvant chemoradiation. The cohort was stratified by receipt of adjuvant chemotherapy. Multiple imputation and a Cox proportional hazards model were employed to estimate the effect of adjuvant chemotherapy on overall survival.

RESULTS

There were 24,418 patients identified in the NCDB with clinically staged II or III rectal cancer who received neoadjuvant chemoradiation. Of these, 5606 (23.0%) had pCR. Among patients with pCR, 1401 (25%) received adjuvant chemotherapy and 4205 (75%) did not. Patients who received adjuvant chemotherapy were slightly younger, more likely to have private insurance, and more likely to have clinically staged III disease, but did not differ significantly in comparison to patients who did not receive adjuvant chemotherapy with respect to race, sex, facility type, Charlson comorbidity score, histologic tumor grade, procedure type, length of stay, or rate of 30-day readmission following surgery. On adjusted analysis, receipt of adjuvant chemotherapy was associated with a lower risk of death at a given time compared to patients who did not receive adjuvant chemotherapy (HR 0.808; 95% CI 0.679-0.961; p = 0.016).

CONCLUSION

Supporting existing NCCN guidelines, the findings from this study suggest that adjuvant chemotherapy improves survival for LARC with pCR following neoadjuvant chemoradiation.

Adjuvant chemotherapy in rectal cancer patients who achieved a pathological complete response after preoperative chemoradiotherapy: a systematic review and meta-analysis

This study evaluated the prognostic impact of ACT in patients who achieved a pathological complete response (pCR). Articles published from January 1990 to September 2018 were searched in EMBASE, PubMed, Ovid, Web of Science, and Cochrane Library. Hazard ratios (HRs) and 95% confidence intervals (CIs) of overall survival (OS) were extracted. Thirteen observational studies were included. There were four National Cancer Database studies with overlapping study periods, thus individual pooled analyses of four different datasets were conducted (n = 3,182, 3,330, 3,575, and 4,739 for pooled analysis sets including Dossa et al., Polanco et al., Xu et al., and Shahab et al., respectively). Although a trend toward improved OS with ACT was observed, statistical significance was not proven (P = 0.09, P = 0.03, P = 0.12, and P = 0.10, respectively). When we performed a stratified analysis comparing the results from single institution and multicenter studies, there was no significant prognostic benefit of ACT. Publication bias was not observed. Routine use of ACT in patients with a pCR could not be warranted from the present meta-analysis. Further study of individual patient data from randomized trials is needed to clarify the role of ACT.

Adjuvant Chemotherapy Seemed Not to Have Survival Benefit in Rectal Cancer Patients with ypTis-2N0 After Preoperative Radiotherapy and Surgery from a Population-Based Propensity Score Analysis

BACKGROUND

Adjuvant chemotherapy is currently offered routinely, as standard, after radical resection for patients with rectal cancer receiving neo-adjuvant chemoradiation. However, the efficacy of adjuvant chemotherapy in patients with ypTis-2N0M0 has not been documented to the same extent, and the survival benefit remained controversial. The purpose of this work was to determine the role of chemotherapy in patients with ypTis-2N0M0 classification.

MATERIALS AND METHODS

Data were obtained from the Surveillance, Epidemiology, and End Results database (n = 4,217). A propensity score model was utilized to balance baseline covariates.

RESULTS

Of the 4,217 included patients, 335 with ypTis-2N0M0 did not receive adjuvant chemotherapy. There were comparable cancer-specific survivals (CSS) between those undergoing adjuvant chemotherapy or not (log-rank test = 0.136, p = .712) in the overall sample. After propensity score matching, the cancer-specific survival did not differ between the chemotherapy and observation groups (log-rank test = 0.089, p = .765). Additionally, the Cox model did not demonstrate adjuvant chemotherapy as the prognostic factor, with hazard ratio = 0.95 (95% confidence interval 0.69-1.32) for CSS. Furthermore, the 10-year cumulative CSS was 78.7% and 79.4% between the chemotherapy and observation groups, indicating no significance, and no impact of adjuvant chemotherapy on survival was observed in different subgroups stratified by T stage, histological grade, histology, lymph nodes, and tumor size.

CONCLUSION

Patients with ypTis-2N0 rectal cancer did not benefit from adjuvant chemotherapy after preoperative radiology and radical surgery in this cohort study. These results provided new insight into the routine use of adjuvant chemotherapy for patients with rectal cancer with completed neo-adjuvant radiotherapy and curative surgery.

IMPLICATIONS FOR PRACTICE

Inconsistent recommendations for patients with rectal cancer receiving neo-adjuvant chemoradiation are offered by clinical guidelines. Adjuvant chemotherapy had no cancer-specific survival benefit, not only in the whole cohort, but also in the propensity score-matched cohort. A Cox model also confirmed adjuvant chemotherapy was not a significant prognostic factor in ypTis-2N0 rectal cancer. No survival benefit conferred by adjuvant chemotherapy was observed, regardless of whether T stage, histological type, grade, lymph nodes and tumor size varied.

Meta-analysis of oxaliplatin-based versus fluorouracil-based neoadjuvant chemoradiotherapy and adjuvant chemotherapy for locally advanced rectal cancer

A meta-analysis was conducted to compare oxaliplatin-based with fluorouracil-based neoadjuvant chemoradiotherapy and adjuvant chemotherapy for locally advanced rectal cancer. MEDLINE, EMBASE and CENTRAL were systematically searched for relevant randomized controlled trials (RCTs) until January 31 2017. Review Manager (version 5.3) was used to analyze the data. Dichotomous data were calculated by odds ratio (OR) with 95% confidence intervals (CI). A total of 8 RCTs with 6103 stage II or III rectal cancer patients were analyzed, including 2887 patients with oxaliplatin+fluorouracil regimen and 3216 patients with fluorouracil alone regimen. Compared with fluorouracil-based regimen group, oxaliplatin-based regimen group attained higher pathologic complete response (OR = 1.29, 95% CI: 1.12−1.49, P = 0.0005) and 3-year disease-free survival (OR = 1.15, 95% CI: 0.93−1.42, P = 0.21), but suffered greater toxicity (OR = 2.07, 95% CI: 1.52−2.83, P < 0.00001). Also, there were no significant differences between two regimens in sphincter-sparing surgery rates (OR = 0.94, 95% CI: 0.83−1.06, P = 0.33), 5-year disease-free survival (OR = 1.15, 95% CI: 0.93−1.42, P = 0.21) and overall survival (3-year, OR = 1.14, 95% CI: 0.98−1.34, P = 0.09; 5-year, OR = 1.06, 95% CI: 0.78−1.44, P = 0.70). In conclusion, the benefits of adding oxaliplatin to fluorouracil-based neoadjuvant chemoradiotherapy and adjuvant chemotherapy for locally advanced rectal cancer remains controversial, and cannot be considered a standard approach.

Adjuvant chemotherapy for patients with ypT0-2N0-category after neoadjuvant chemoradiotherapy for rectal cancer

Locally advanced rectal cancer patients with ypT0-2N0 have good prognosis and may not require as many cycles of adjuvant chemotherapy as patients with a poor (ypT3-4 or N+) response. The aim of the present study was to evaluate the three-year disease-free and overall survival between patients with ypT0-2N0 rectal adenocarcinoma who received 0-3 cycles of 5-fluorouracil-based adjuvant chemotherapy and those who received >3 cycles. A total of 106 patients with locally advanced rectal cancer, classified as ypT0-2N0 after surgery at the Fudan University Shanghai Cancer Center (Shanghai, China) between 2006 and 2012, were identified. The patients were divided into two groups depending on the number of cycles of adjuvant chemotherapy: Group 1 received 0-3 cycles (n=32) and group 2 received ≥4 cycles of adjuvant chemotherapy (n=74). The three-year disease-free survival and overall survival rates were 86.8 and 93.1% for group 1 (P=0.633), and 88.5 and 96.8% for group 2 (P=0.381). No statistically significant difference was observed between the two groups, suggesting that patients with ypT0-2N0 status may not require more than three cycles of post-operative chemotherapy. Further evaluation in prospective studies is urgently recommended.

Oncologic Outcome of ypT1-2N0 Rectal Cancer After Neoadjuvant Chemoradiotherapy Compared With pT1-2N0 Rectal Cancer

OBJECTIVE

To investigate the oncologic outcome of ypT1-2N0 mid and lower rectal cancer after chemoradiotherapy (CRT) compared with pT1-2N0 rectal cancer.

METHODS

We compared the oncologic outcome of patients with mid and lower rectal cancer who underwent preoperative CRT and who did not, between February 2005 and August 2012.

RESULTS

Compared with patients who did not receive preoperative CRT, patients who received preoperative CRT did not have significantly different clinicopathologic features except clinical stage and distal resection margin. The 5-year disease-free survival (DFS) rates were lower in patients who received preoperative CRT than those who did not (84.4% vs. 95.5%, P=0.029). Preoperative CRT was a prognostic factor affecting 5-year DFS in patients with pathologically proven stage T1N0 mid and lower rectal cancer (HR, 11.157; 95% CI, 1.735-71.762; P=0.011) CONCLUSIONS:: ypT2N0 rectal cancer after neoadjuvant CRT showed shorter DFS compared with pT2N0 rectal cancer.

The potential predictive value of MRI and PET-CT in mucinous and nonmucinous rectal cancer to identify patients at high risk of metastatic disease

OBJECTIVE

To correlate imaging parameters from baseline MRI diffusion-weighted imaging (DWI) and fludeoxyglucose (FDG) positron emission tomography (PET)-CT with synchronous and metachronous metastases in mucinous carcinoma (MC) and non-mucinous carcinoma (NMC) rectal cancer.

METHODS

111 patients with extraperitoneal locally advanced rectal cancer, who underwent pelvic MRI, DWI and FDG PET-CT, were stratified into MC (n = 23) and NMC (n = 88). We correlated adverse morphologic features on MRI [mT4, mesorectal fascia involvement, extramural venous invasion (mEMVI), mN2] and quantitative imaging parameters [minimum apparent diffusion coefficient (ADC_min), maximum standardized uptake value, total lesion glycolysis, metabolic tumour volume, T₂ weighted and DWI tumour volumes] with the presence of metastatic disease. All patients underwent pre-operative chemoradiation therapy (CRT); 100/111 patients underwent surgery after CRT and were classified as pathological complete response (PCR) and no PCR [tumour regression grade (TRG)1 vs TRG2-5] and as ypN0 and ypN1-2. Median follow-up time was 48 months. Metastases were confirmed on FDG PET-CT and contrast-enhanced multidetector CT.

RESULTS

The percentage of mucin measured by MRI correlates with that quantified by histology. On multivariate analysis, the synchronous metastases were correlated with mEMVI [odds ratio (OR) = 21.48, p < 0.01] and low ADC_min (OR = 0.04, p = 0.038) in NMC. The difference of metachronous recurrence between the MC group (10-90% mucin) and NMC group was significant (p < 0.01) (OR = 21.67, 95% confidence interval 3.8-120.5). Metachronous metastases were correlated with ypN2 (OR = 8.24, p = 0.01) in MC and in NMC. In NMC, mEMVI correlated with no PCR (p = 0.018) and ypN2 (p < 0.01).

CONCLUSION

mEMVI could identify patients with NMC, who are at high risk of synchronous metastases. The MC group is at a high risk of developing metachronous metastases. Advances in knowledge: Patients at high risk of metastases are more likely to benefit from more aggressive neoadjuvant therapy.

YpT1-2N0 rectal cancer after neoadjuvant chemoradiation has lower survival compared with pT1-2N0 rectal cancer

Pathologic T1-2N0 rectal cancer shows an excellent prognosis without preoperative or postoperative chemoradiation. However, oncologic outcome of ypT1-2N0 remains unclear and undetermined. Thus, the aim of this study was to compare the survival of ypT1-2 and pT1-2 rectal cancer patients after radical resection and identify risk factors of ypT1-2 rectal cancer in Surveillance, Epidemiology, and End Results Program (SEER)-registered rectal cancer patients. The results showed that ypT1-2N0 rectal cancer after neoadjuvant chemoradiation has lower survival compared with pT1-2N0 rectal cancer and mucinous/signet-ring cancer and less than 12 lymph nodes retrieval were two risk factors in ypT1-2 patients. These results suggest that ypT1-2 patients with one or two risk factors may benefit from postoperative adjuvant chemotherapy.

Is adjuvant chemotherapy necessary for patients with pathological complete response after neoadjuvant chemoradiotherapy and radical surgery in locally advanced rectal cancer? Long-term analysis of 40 ypCR patients at a single center

OBJECTIVES

According to practice guidelines, adjuvant chemotherapy (ACT) is required for all patients with locally advanced rectal cancer who have received neoadjuvant chemoradiotherapy (NCRT) and total mesorectal excision (TME). The objective of this study was to determine whether ACT is necessary for patients achieving pathological complete response (pCR) after NCRT followed by surgery.

METHODS

By retrospectively reviewing a prospectively collected database in our single tertiary care center, 210 patients with locally advanced rectal cancer who underwent NCRT followed by TME were identified between February 2005 and August 2013. All patients achieving ypCR were enrolled in this study, in which who underwent ACT (chemo group) and who did not (non-chemo group) were compared in terms of local recurrence (LR) rate, 5-year disease-free survival (DFS) rate and overall survival (OS) rate.

RESULTS

Forty consecutive patients with ypCR were enrolled, 19 (47.5 %) in chemo group and 21 (52.5 %) in non-chemo group. After a median follow-up of 57 months, five patients developed systemic recurrences, with the 5y-DFS rate of 83.5 %. No LR occurred in the two groups. The 5y-DFS rates for patients in chemo group and non-chemo group was 90.9 and 76.0 %, respectively, showing no statistically significant difference (p = 0.142). Multivariate analysis showed that tumor grade was the only independent prognostic factor for 5y-DFS and 5y-OS.

CONCLUSIONS

Results of this study suggested that it may not be necessary for all rectal cancer patients with ypCR after NCRT and radical surgery to receive ACT. Prospective randomized trials are warranted to further determine the value of ACT for ypCR patients.

Adjuvant chemotherapy for rectal cancer: Is it needed?

Adjuvant chemotherapy has become a standard treatment of advanced rectal cancer in the West. The benefits of adjuvant chemotherapy after surgery alone have been well established. However, controversy surrounds the use adjuvant chemotherapy in patients who received preoperative chemoradiotherapy, despite it being recommended by a number of international guidelines. Results of recent multicentre randomised control trials showed no benefit of adjuvant chemotherapy in terms of survival and rates of distant metastases. However, concerns exist regarding the quality of the studies including inadequate staging modalities, out-dated chemotherapeutic regimens and surgical approaches and small sample sizes. It has become evident that not all the patients respond to adjuvant chemotherapy and more personalised approach should be employed when considering the benefits of adjuvant chemotherapy. The present review discusses the strengths and weaknesses of the current evidence-base and suggests improvements for future studies.

Rectal cancer patients after neoadjuvant radiotherapy (30Gy/10f) with negative lymph node may not benefit from postoperative adjuvant chemotherapy: a retrospective study

OBJECTIVE

The purpose of this study is to evaluate whether adjuvant chemotherapy could bring oncologic benefit to all patients who underwent neoadjuvant radiotherapy (30Gy/10f).

METHODS

Rectal cancer patients receiving preoperative radiotherapy between July 2002 and April 2009 were retrospectively identified.

RESULTS

A total of 225 patients were enrolled in this study. One hundred thirty-one patients received postoperative adjuvant chemotherapy, and 94 patients did not. The 120 ypN+ and 105 ypN- patients were divided into chemo and non-chemo groups. Two groups of patients did not show any significant difference in terms of gender, age, ypT stage, preoperative serum carcinoembryonic antigen (CEA) level, differentiation, circumferential margin (CRM), lymphovascular invasion (LVI), surgical approach, local recurrence, and distant metastasis (P > 0.05). Survival analysis showed that in ypN+ patients, the 5-year overall survival (OS) rate and 5-year disease-free survival (DFS) rate in chemo group were both significantly higher than non-chemo group (P < 0.05). In ypN- patients, the 5-year OS rate and 5-year DFS rate did not show any significant difference in the two groups (P > 0.05). Subgroup analysis showed that the 5-year OS rate and 5-year DFS rate in ypT0-2 N- patients (P > 0.05) and ypT3-4 N- patients (P > 0.05) did not show any significant difference, either.

CONCLUSIONS

Based on a Chinese protocol, patients with ypN- stage may not benefit from adjuvant chemotherapy, regardless of the ypT stage, while the ypN+ patients may benefit from adjuvant chemotherapy. More randomized clinical trials are needed in the future.

Oncologic results and prognostic predictors of patients with locally advanced rectal cancer showing ypN0 after radical surgery following neoadjuvant chemoradiotherapy

PURPOSE

Adjuvant chemotherapy is recommended for patients with locally advanced rectal cancer after radical surgery following neoadjuvant chemoradiotherapy (NCRT) regardless of the final pathologic stage. However, the efficacy of adjuvant chemotherapy in ypN0 patients remains controversial. The aim of this study was to evaluate the oncologic outcomes and analyze the prognostic factors for ypN0 patients in order to estimate prognosis and establish an effective adjuvant chemotherapy strategy for stage 0-II rectal cancers after radical surgery following NCRT.

METHODS

Between January 1999 and December 2009, the medical records of 202 patients who had been diagnosed with locally advanced rectal cancer, underwent radical surgery following NCRT, and showed ypN0 were retrospectively reviewed.

RESULTS

The median follow-up period was 60.5 months. The 5-year local recurrence rate was 3.1 %. The 5-year disease-free survival and 5-year overall survival were 86.3 and 86.9 %. Postirradiation T3-4 and abdominoperineal resection (APR) were the independent prognostic indicators for disease-free survival (p = 0.001, p = 0.003) and overall survival (p = 0.001, p = 0.002). Adjuvant chemotherapy improved local recurrence in the patient with ypT3-4 and patients who had undergone APR (p = 0.014, p = 0.002). APR affected local recurrence, disease-free survival, and overall survival of ypT3-4 patients (p = 0.013. 0.029, and 0.001) CONCLUSIONS: Postirradiation T3-4 and APR are the significant prognostic factors for ypN0. Further randomized prospective study is needed to evaluate the oncologic benefit of adjuvant chemotherapy in ypN0 patients, especially those with ypT3-4 and those having undergone APR, and to confirm which chemotherapeutic agent could improve the oncologic outcomes of patients poorly responding to NCRT.

Advances and challenges in treatment of locally advanced rectal cancer

Dramatic improvements in the outcomes of patients with rectal cancer have occurred over the past 30 years. Advances in surgical pathology, refinements in surgical techniques and instrumentation, new imaging modalities, and the widespread use of neoadjuvant therapy have all contributed to these improvements. Several questions emerge as we learn of the benefits or lack thereof for components of the current multimodality treatment in subgroups of patients with nonmetastatic locally advanced rectal cancer (LARC). What is the optimal surgical technique for distal rectal cancers? Do all patients need postoperative chemotherapy? Do all patients need radiation? Do all patients need surgery, or is a nonoperative, organ-preserving approach warranted in selected patients? Answering these questions will lead to more precise treatment regimens, based on patient and tumor characteristics, that will improve outcomes while preserving quality of life. However, the idea of shifting the treatment paradigm (chemoradiotherapy, total mesorectal excision, and adjuvant therapy) currently applied to all patients with LARC to a more individually tailored approach is controversial. The paradigm shift toward organ preservation in highly selected patients whose tumors demonstrate clinical complete response to neoadjuvant treatment is also controversial. Herein, we highlight many of the advances and resultant controversies that are likely to dominate the research agenda for LARC in the modern era.

Management of oligometastatic rectal cancer: is liver first?

Twenty percent of patients with rectal cancer present with synchronous liver metastases at the time of initial diagnosis. These patients can be treated with a curative intent, although the choice and sequence of treatment modalities are not well established and are commonly debated in multi-disciplinary tumor boards. In this article we review clinical evidence for various treatment approaches and attempt to formulate a pathway for clinicians to use in evaluating and managing these patients.

Diffusion-weighted imaging of the male pelvis

Diffusion-weighted (DW) imaging is playing an increasingly important role in disease detection, prognostication, and monitoring of treatment response. Particularly in the realm of oncology, the potential applications for DW imaging continue to expand. In this article, the authors detail the role of DW imaging for pathologic processes involving the male pelvis. The authors describe the current data, new insights, and ongoing controversies regarding DW imaging of the male pelvis with a particular emphasis on oncologic applications. The authors also discuss imaging techniques and common pitfalls for DW imaging in this anatomic region.

Impression of prognosis regarding pathologic stage after preoperative chemoradiotherapy in rectal cancer

AIM: To ascertain pathologic stage as a prognostic indicator for rectal cancer patients receiving preoperative chemoradiotherapy (PCRT).

METHODS: Patients with mid- and low rectal carcinoma (magnetic resonance imaging - based clinical stage II or III) between 2000 and 2009 and treated with curative radical resection were identified. Patients were divided into two groups: PCRT and No-PCRT. Recurrence-free survival (RFS) was examined according to pathologic stage and addition of adjuvant treatment.

RESULTS: Overall, 894 patients were identified. Of these, 500 patients received PCRT. Adjuvant chemotherapy was delivered to 81.5% of the No-PCRT and 94.8% of the PCRT patients. Adjuvant radiotherapy was given to 29.4% of the patients in the No PCRT group. The 5-year RFS for the No-PCRT group was 92.6% for Stage I, 83.3% for Stage II, and 72.9% for Stage III. The 5-year RFS for the PCRT group was 95.2% for yp Stage 0, 91.7% for yp Stage I, 73.9% for yp Stage II, and 50.7% for yp Stage III.

CONCLUSION: Pathologic stage can predict prognosis in PCRT patients. 5-year RFS is significantly lower among PCRT patients than No-PCRT patients in pathologic stage II and III. These results should be taken into account when considering adjuvant treatment for patients treated with PCRT.

Clinical outcome of patients with complete pathological response to neoadjuvant chemoradiotherapy for locally advanced rectal cancers: the Indian scenario

Introduction. Neoadjuvant chemoradiotherapy and total mesorectal excision are considered the standard treatment for locally advanced rectal cancer. Various studies have reported pathological downstaging and a complete pathological response rate of 15%-27% following neoadjuvant chemoradiotherapy which has translated into improved survival. We endeavour to determine the clinical outcome of patients attaining a complete pathological tumor response following neoadjuvant chemoradiotherapy in the Indian setting where most of our patient population is younger and presents with aggressive tumor biology. Materials and Methods. Clinicopathological and treatment details were recorded for 64 patients achieving pathological complete response from 2010 to 2013. Disease-free survival (DFS), overall survival (OS), and locoregional and systemic recurrence rates were evaluated for these patients. Results. After a median follow-up of 30.5 months (range 11-59 months), the 3-year overall survival (OS) was 94.6% and the 3-year disease-free survival (DFS) was 88.5%. The locoregional and systemic recurrence rates were 4.7% and 3.1%, respectively. Conclusion. In the Indian subcontinent, despite younger patients with aggressive tumor biology, outcome in complete responders is good.

Adjuvant chemotherapy after neoadjuvant chemoradiation and curative resection for rectal cancer: is it necessary for all patients?

BACKGROUND

The benefit of adjuvant chemotherapy for patients with locally advanced rectal cancer who have received neoadjuvant concurrent chemoradiation therapy (CCRT) and undergone curative resection remains unclear.

METHODS

This study was a retrospective review of prospectively collected data. Patients with locally advanced rectal cancer who underwent curative surgery after neoadjuvant CCRT between January 2006 and March 2011 were identified. Four hundred forty-one patients who completed adjuvant chemotherapy (chemo group) were compared with 35 patients who did not receive any adjuvant treatment (nonchemo group).

RESULTS

The 5-year disease-free survival (DFS) was significantly higher in the chemo group (78.5% vs. 63.1%, P =  0.016). After stratification of the patients according to nodal status, these differences were no longer significant, but there were trends toward inferior DFS in the nonchemo group in all survival curves. In multivariate Cox regression analysis, no adjuvant chemotherapy (HR, 2.306; 95% CI, 1.101-4.829; P = 0.027) emerged as an independent prognostic factor associated with decreased DFS.

CONCLUSIONS

Adjuvant chemotherapy was significantly associated with increased DFS among patients who had undergone neoadjuvant CCRT and radical resection for locally advanced rectal cancer. Adjuvant chemotherapy should be considered in every patient after neoadjuvant CCRT irrespective of the final pathology stage.

Which is the best postoperative chemotherapy regimen in patients with rectal cancer after neoadjuvant therapy?

Background

There is no general agreement about whether patients who have already received neoadjuvant chemoradiotherapy need further postoperative chemotherapy based on 5-fluorouracil(5-FU) or 5-FU plus oxaliplatin.

Methods

Medicare beneficiaries from 1992 to 2008 with Union for International Cancer Control ypStages I to III primary carcinoma of the rectum who underwent 5-FU-based neoadjuvant chemoradiotherapy and surgery for curative intent were identified through the Surveillance, Epidemiology, and End Results (SEER)-Medicare-linked database. A Cox proportional hazards model and propensity score-matched techniques were used to evaluate the effect of treatment on survival.

Results

For patients with resected rectal cancer who have already received 5-FU-based neoadjuvant chemoradiotherapy, postoperative 5-FU-based chemotherapy did not prolong cancer-specific survival (CSS) in ypStage I (P = 0.960) and ypStage II (P = 0.134); however, it significantly improved the CSS in ypStage III (hazard ratio = 1.547, 95% CI = 1.101-2.173, P = 0.012). No significant differences in survival between the 5-FU group and oxaliplatin group were observed.

Conclusions

For patients with resected rectal cancer who have already received 5-FU-based neoadjuvant chemoradiotherapy, postoperative 5-FU-based chemotherapy prolongs the CSS of groups in ypStage III. Adding oxaliplatin to fluoropyrimidines in the postoperative chemotherapy did not improve the CSS for patients who received neoadjuvant chemoradiotherapy.

Electronic supplementary material

The online version of this article (doi:10.1186/1471-2407-14-888) contains supplementary material, which is available to authorized users.

No benefit of adjuvant Fluorouracil Leucovorin chemotherapy after neoadjuvant chemoradiotherapy in locally advanced cancer of the rectum (LARC): Long term results of a randomized trial (I-CNR-RT)

BACKGROUND AND PURPOSE

To evaluate the effect of adjuvant chemotherapy (ACT) in locally advanced rectal cancer (LARC) after neoadjuvant chemoradiation (NACT-RT). The study was funded by the Italian National Research Council (CNR).

METHODS

From September 1992 to January 2001, 655 patients with LARC (clinically T3-4, any N) treated with NACT-RT and surgery, were randomized in two arms: follow-up (Arm A) or 6 cycles of ACT with 5 fluorouracil (5FU)-Folinic Acid (Arm B). NACT-RT consisted of 45Gy/28/ff concurrent with 5FU (350mg/sqm) and Folinic Acid (20mg/sqm) on days 1-5 and 29-33; surgery was performed after 4-6weeks. Median follow up was 63·7months. Primary end point was overall survival (OS).

RESULTS

634/655 patients were evaluable (Arm A 310, Arm B 324); 92·5% of Arm A and 91% of Arm B patients received the preoperative treatment as in the protocol; 294 patients of Arm A (94·8%) and 296 of Arm B (91·3%) underwent a radical resection; complete pathologic response and overall downstaging rates did not show any significant difference in the two arms. 83/297 (28%) patients in Arm B, never started ACT. Five year OS and DFS did not show any significant difference in the two treatment arms. Distant metastases occurred in 62 patients (21%) in Arm A and in 58 (19·6%) in Arm B.

CONCLUSIONS

In patients with LARC treated with NACT-RT, the addition of ACT did not improve 5year OS and DFS and had no impact on the distant metastasis rate.

Overview of radiation therapy for treating rectal cancer

A major outcome of importance for rectal cancer is local control. Parallel to improvements in surgical technique, adjuvant therapy regimens have been tested in clinical trials in an effort to reduce the local recurrence rate. Nowadays, the local recurrence rate has been reduced because of both good surgical techniques and the addition of radiotherapy. Based on recent reports in the literature, preoperative chemoradiotherapy is now considered the standard of care for patients with stages II and III rectal cancer. Also, short-course radiotherapy appears to provide effective local control and the same overall survival as more long-course chemoradiotherapy schedules and, therefore, may be an appropriate choice in some situations. Capecitabine is an acceptable alternative to infusion fluorouracil in those patients who are able to manage the responsibilities inherent in self-administered, oral chemotherapy. However, concurrent administration of oxaliplatin and radiotherapy is not recommended at this time. Radiation therapy has long been considered an important adjunct in the treatment of rectal cancer. Although no prospective data exist for several issues, we hope that in the near future, patients with rectal cancer can be treated by using the best combination of surgery, radiation therapy, and chemotherapy in near future.

Coexistence of perineural invasion and lymph node metastases is a poor prognostic factor in patients with locally advanced rectal cancer after preoperative chemoradiotherapy followed by radical resection and adjuvant chemotherapy

OBJECTIVE

To determine the role of lymph node metastases (ypN) and perineural invasion (PNI) in patients with locally advanced rectal cancer (LARC).

SUBJECTS AND METHODS

Eighty-eight LARC patients receiving preoperative chemoradiotherapy from April 2006 to November 2011 were enrolled in this study. Univariate and multivariate analyses were conducted to determine the association between clinicopathologic features and clinical outcome.

RESULTS

The presence of ypN (p = 0.011) and PNI (p = 0.032) was a significant adverse prognostic factor for disease-free survival (DFS). High histologic grade (p = 0.015), PNI+ (p = 0.043) and ypN+ (p = 0.041) were adverse prognostic factors for overall survival (OS). Positive PNI was significantly associated with a higher risk of distant failure (odds ratio = 6.09; 95% CI: 1.57-27.05; p = 0.008). Moreover, patients with a coexistence of ypN+ and PNI+ had the significantly worst DFS (p < 0.001) and OS rates (p < 0.001) compared with other phenotypes.

CONCLUSIONS

The presence of either PNI or ypN was a significant prognostic factor for predicting poor survival rates in LARC patients, especially those with a coexistence of both factors. Accordingly, we recommend an intensive follow-up and therapeutic programs for LARC patients with simultaneous PNI+ and ypN+.

Intraoperative staging by surgeons in patients with rectal cancer after preoperative chemoradiation: diagnostic accuracy and prognostic value

PURPOSE

Prognostic significance of intraoperative staging by surgeons and its possible complementary role with the pathological stage for evaluating the prognosis of rectal cancer after preoperative chemoradiation (CRT) is unknown. The goal of this study is to evaluate the diagnostic accuracy and prognostic role of intraoperative surgical staging by surgeons in patients with rectal cancer after preoperative CRT.

METHODS

A total of 267 consecutive patients with rectal cancer who underwent preoperative CRT and radical resection from December 2007 to March 2010 were retrospectively reviewed. Surgical staging was evaluated by determining its diagnostic accuracy and analyzing its prognostic significance.

RESULTS

Sensitivity, specificity, positive predictive value, and negative predictive value of intraoperative diagnosis of good responders (ypT0-2) were 78, 67, 53, and 86 %, respectively. The overall accuracy of good responders by surgeons was 71 %. A multivariate analysis revealed that pretreatment N stage and maximal tumor diameter were independent predictors for accordance of surgical and pathological diagnoses in T staging. The 3-year disease-free survival rates of the patients with surgical T0, T1, T2, T3, and T4 were 100, 94, 85, 84, and 58 %, respectively, and 86, 81, and 67 % for patients with surgical N0, N1, and N2 disease, respectively (P < 0.001 and P = 0.022, respectively). On multivariate analysis, surgical T stage was an independent prognostic factor for both disease-free survival and local recurrence.

CONCLUSION

Intraoperative surgical tumor staging by surgeons may be an important predictor of survival in patients with rectal cancer after preoperative CRT.

Adjuvant treatment for locally advanced rectal cancer patients after preoperative chemoradiotherapy: when, and for whom?

BACKGROUND

The standard treatment for patients with locally advanced rectal cancer (clinical tumor, node, metastases [TNM] stage II or III) is radiotherapy before surgery (with or without concomitant fluoropyrimidine-based chemotherapy) followed by surgery. The role of adjuvant chemotherapy in this setting of patients is controversial in terms of the overall benefit on survival, the subgroup of patients who might not need it, and the best regimen (combination regimens vs. fluoropyrimidine alone).

PATIENTS AND METHODS

Based on the retrospective analysis of the clinical outcome of all patients with locally advanced rectal adenocarcinoma treated at our institute during the past 9 years, we comment on prognostic factors for local and distant metastases of patients who received neoadjuvant treatment followed by surgery, and the scientific evidence that can help to decide the adjuvant chemotherapy.

RESULTS

We conclude that pathological TNM stage after neoadjuvant chemoradiation (ypTNM) stage after surgery significantly affects disease-free and overall survival. In particular, patients with pathologically positive lymph nodes (ypN+) after surgery have a high probability of developing distant metastases.

CONCLUSION

ypN+ patients are candidate for intensified adjuvant chemotherapy.

Current issues in locally advanced colorectal cancer treated by preoperative chemoradiotherapy

In patients with locally advanced rectal cancer, preoperative chemoradiotherapy has proven to significantly improve local control and cause lower treatment-related toxicity compared with postoperative adjuvant treatment. Preoperative chemoradiotherapy followed by total mesorectal excision or tumor specific mesorectal excision has evolved as the standard treatment for locally advanced rectal cancer. The paradigm shift from postoperative to preoperative therapy has raised a series of concerns however that have practical clinical implications. These include the method used to predict patients who will show good response, sphincter preservation, the application of conservative management such as local excision or “wait-and-watch” in patients obtaining a good response following preoperative chemoradiotherapy, and the role of adjuvant chemotherapy. This review addresses these current issues in patients with locally advanced rectal cancer treated by preoperative chemoradiotherapy.

Prognostic implications of the lymph node count after neoadjuvant treatment for rectal cancer

BACKGROUND

The aim of this study was to investigate the effect of neoadjuvant chemoradiotherapy on the lymph node yield of rectal cancer surgery.

METHODS

Data for patients who underwent neoadjuvant chemoradiotherapy followed by surgery for resectable rectal cancer from June 1992 to June 2009 were reviewed. The primary outcomes measured were the number of lymph nodes retrieved, their status, and patient survival.

RESULTS

In total, 345 patients underwent neoadjuvant chemoradiotherapy followed by surgery, and 95 patients had surgery alone. Neoadjuvant chemoradiotherapy decreased both the median (range) number of lymph nodes retrieved (7 (1-33) versus 12.5 (0-44) respectively; P < 0.001) and the number of positive lymph nodes (0 (0-11) versus 0 (0-16); P = 0.001). After neoadjuvant chemoradiotherapy, the number of retrieved lymph nodes was inversely correlated with tumour regression, and with the interval between treatment and surgery. The 5-year overall and disease-free survival rates were 86.5 and 79.1 per cent respectively. After neoadjuvant therapy, lymph node status was found to be an independent predictor of survival, whereas the number of retrieved lymph nodes did not represent a prognostic factor for either overall or disease-free survival.

CONCLUSION

Low lymph node count after neoadjuvant chemoradiotherapy for rectal cancer does not signify an inadequate resection or understaging, but represents an increased sensitivity to the treatment.

ypN0 nodal status after neoadjuvant chemoradiotherapy for rectal carcinoma is not associated with adverse prognosis as compared with pN0 after primary surgery

BACKGROUND AND AIMS

Neoadjuvant chemoradiotherapy (nCRT) has been established as standard treatment for locally advanced rectal cancer (cT3/4 or cN+ cM0, distance from circumferential resection margin ≤1 mm) to enhance local disease control and minimize the rate of locoregional recurrence. As a consequence of downstaging, a significant proportion of patients show non-viable tumor deposits within regional lymph nodes that qualify as ypN0 according to the current TNM classification irrespective of the actual pre-treatment status. Accordingly, the prognostic relevance of ypN0 status as compared with true pN0 without preceding nCRT is not known.

PATIENTS AND METHODS

We retrospectively analyzed 132 patients who underwent standard total mesorectal excision (TME) surgery after nCRT for rectal carcinoma and were classified as ypN0, and compared their prognoses with those of 341 patients with pN0 without nCRT.

RESULTS

Re-evaluation of regional lymph nodes after nCRT showed no evidence of previous metastasis in 91 cases (ypN0(-)), sure but non-viable metastasis in 14 patients (ypN0(+)), and unsure status in 27 patients (ypN0(X)). The local recurrence rate, distant metastases, and disease-free, observed, and cancer-related survival were similar in all subgroups (p = 0.447, 0.695, 0.759, 0.655, and 0.354, respectively).

CONCLUSION

Our results showed a similar outcome in patients with ypN0 and in the control group with pN0 regarding local recurrence rate, distant metastases, and disease-free, observed, and cancer-related survival. Validation of these results is necessary to clarify the questions regarding postoperative adjuvant chemotherapy for patients with ypN0(+).

A prognostic model comprising pT stage, N status, and the chemokine receptors CXCR4 and CXCR7 powerfully predicts outcome in neoadjuvant resistant rectal cancer patients

Despite the optimization of the local treatment of advanced rectal cancer (LARC), combination of preoperative chemoradiotherapy (CRT) and surgery, approximately one third of patients will develop distant metastases. Since the chemokine receptor CXCR4 has been implicated in metastasis development and prognosis in colorectal cancer, the role of the entire axis CXCR4-CXCL12-CXCR7 was evaluated to identify high relapse risk rectal cancer patients. Tumor specimens of 68 LARC patients undergoing surgery after neoadjuvant-CRT were evaluated for CXCR4, CXCR7, and CXCL12 expression through immunohistochemistry. Multivariable prognostic model was developed using classical prognostic factors along with chemokine receptor expression profiles. High CXCR4 correlated with a shorter relapse-free survival (RFS) (p = 0.0006) and cancer specific survival (CSS) (p = 0.0004). Concomitant high CXCR4-negative/low CXCR7 or high CXCR4-negative/low CXCL12 significantly impaired RFS (p = 0.0003 and p = 0.0043) and CSS (p = 0.0485 and p = 0.0026). High CXCR4/N+ identified the worst prognostic category for RFS (p < 0.0001) and CSS (p = 0.0003). The optimal multivariable predictive model for RFS was a five-variable model consisting of gender, pT stage, N status, CXCR4, and CXCR7 (AUC = 0.92, 95% CI = 0.77-0.98). The model is informative and supportive for adjuvant treatment and identifies CXCR4 as a new therapeutic target in rectal cancer.

Selective use of adjuvant chemotherapy for rectal cancer patients with ypN0

BACKGROUND

The administration of adjuvant chemotherapy for rectal cancer patients with ypN0 is controversial. The purposes of this study were to evaluate the role of adjuvant chemotherapy in ypN0 patients and to optimize its use for these patients.

METHODS

We performed a retrospective study of 160 rectal cancer patients who had the final pathology of ypN0 between March 2003 and November 2010. Overall survival (OS), disease-free survival (DFS), local recurrence-free survival (LRFS), and distant metastasis-free survival (DMFS) were compared between patients who did and did not receive adjuvant chemotherapy. Multivariate analysis was performed to explore clinical factors significantly associated with DFS, LRFS, and DMFS.

RESULTS

For ypT0-2N0 patients, the 5-year OS, DFS, LRFS, and DMFS were similar between patients who did and did not receive adjuvant chemotherapy (P > 0.05). For patients with ypT3-4N0, those who were given adjuvant chemotherapy exhibited a higher 5-year OS than those who were not (P = 0.026), with also an extended 5-year DFS (P = 0.050). Further analysis indicated that adjuvant chemotherapy could decrease the rates of distant metastases for ypT3-4N0 patients with no impact on local control. In multivariable analysis, both the final pathological stage and adjuvant chemotherapy were independent predictors of DMFS for the whole group. When stratified by pathological stage, adjuvant chemotherapy was still significantly associated with DMFS in the ypT3-4 stratum.

CONCLUSIONS

Adjuvant chemotherapy may not improve survival for ypT0-2N0 patients. However, it may be clinically meaningful for ypT3-4N0 patients by decreasing rates of distant metastases. Further randomized controlled clinical trials are needed to address this problem.

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

BACKGROUND AND PURPOSE

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

PATIENTS AND METHODS

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

RESULTS

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

CONCLUSION

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

Pathological complete response after neoadjuvant therapy for rectal cancer and the role of adjuvant therapy

Both the addition of neoadjuvant chemoradiation therapy and improvements in surgical techniques have improved local control and overall survival for locally advanced rectal cancer patients over the past few decades. The addition of adjuvant chemotherapy has likely improved outcomes as well, though the contribution has been more difficult to quantify. At present, the majority of resected locally advanced rectal cancer patients receive adjuvant chemotherapy, though there is great variability in this practice based on both patient and institution characteristics. Recently, questions have been raised regarding which sub-groups of patients benefit most from adjuvant chemotherapy. As pathologic complete response (pCR) is increasingly found to be a reasonable surrogate for long-term favorable outcomes, some have questioned the need for adjuvant therapy in this select group of patients. Multiple retrospective analyses have shown minimal to no benefit for adjuvant chemotherapy in this group. Indeed, the patients most consistently shown to benefit from adjuvant therapy both in terms of disease free survival (DFS) and overall survival (OS) are those who achieve an intermediate pathologic response to neoadjuvant treatment. Tumors that have high expression of thymidylate synthetase have also shown to benefit from adjuvant therapy. More study is needed into clinical and molecular features that predict patient benefit from adjuvant therapy.

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.

Postoperative adjuvant chemotherapy use in patients with stage II/III rectal cancer treated with neoadjuvant therapy: a national comprehensive cancer network analysis

PURPOSE

Practice guidelines recommend that patients who receive neoadjuvant chemotherapy and radiation for locally advanced rectal cancer complete postoperative adjuvant systemic chemotherapy, irrespective of tumor downstaging.

PATIENTS AND METHODS

The National Comprehensive Cancer Network (NCCN) Colorectal Cancer Database tracks longitudinal care for patients treated at eight specialty cancer centers across the United States and was used to evaluate how frequently patients with rectal cancer who were treated with neoadjuvant chemotherapy also received postoperative systemic chemotherapy. Patient and tumor characteristics were examined in a multivariable logistic regression model.

RESULTS

Between September 2005 and December 2010, 2,073 patients with stage II/III rectal cancer were enrolled in the database. Of these, 1,193 patients receiving neoadjuvant chemoradiotherapy were in the analysis, including 203 patients not receiving any adjuvant chemotherapy. For those seen by a medical oncologist, the most frequent reason chemotherapy was not recommended was comorbid illness (25 of 50, 50%); the most frequent reason chemotherapy was not received even though it was recommended or discussed was patient refusal (54 of 74, 73%). After controlling for NCCN Cancer Center and clinical TNM stage in a multivariable logistic model, factors significantly associated with not receiving adjuvant chemotherapy were age, Eastern Cooperative Oncology Group performance status ≥ 1, on Medicaid or indigent compared with private insurance, complete pathologic response, presence of re-operation/wound infection, and no closure of ileostomy/colostomy.

CONCLUSION

Even at specialty cancer centers, a sizeable minority of patients with rectal cancer treated with curative-intent neoadjuvant chemoradiotherapy do not complete postoperative chemotherapy. Strategies to facilitate the ability to complete this third and final component of curative intent treatment are necessary.

Early FDG PET response assessment of preoperative radiochemotherapy in locally advanced rectal cancer: correlation with long-term outcome

PURPOSE

The aim of the present study is to prospectively evaluate the prognostic value of previously defined [(18)F]2-fluoro-2-deoxy-D-glucose positron emission tomography (FDG PET) criteria of early metabolic response in patients with locally advanced rectal cancer (LARC) after long-term follow-up.

METHODS

Forty-two patients with poor prognosis LARC underwent three biweekly courses of chemotherapy with oxaliplatin, raltitrexed and 5-fluorouracil modulated by levofolinic acid during pelvic radiotherapy. FDG PET studies were performed before and 12 days after the beginning of the chemoradiotherapy (CRT) treatment. Total mesorectal excision (TME) was carried out 8 weeks after completion of CRT. A previously identified cutoff value of ≥52 % reduction of the baseline mean FDG standardized uptake value (SUV(mean)) was applied to differentiate metabolic responders from non-responders and correlated to tumour regression grade (TRG) and survival.

RESULTS

Twenty-two metabolic responders showed complete (TRG1) or subtotal tumour regression (TRG2) and demonstrated a statistically significantly higher 5-year relapse-free survival (RFS) compared with the 20 non-responders (86 vs 55 %, p = .014) who showed TRG3 and TRG4 pathologic responses. A multivariate analysis demonstrated that early ∆SUV(mean) was the only pre-surgical parameter correlated to the likelihood of recurrence (p = .05).

CONCLUSION

This study is the first prospective long-term evaluation demonstrating that FDG PET is not only an early predictor of pathologic response but is also a valuable prognostic tool. Our results indicate the potential of FDG PET for optimizing multidisciplinary management of patients with LARC.

Oncologic outcome after preoperative chemoradiotherapy in patients with pathologic T0 (ypT0) rectal cancer

BACKGROUND

Little is known about the oncologic outcomes of patients with ypT0 rectal cancer after preoperative chemoradiotherapy.

OBJECTIVE

To evaluate the clinicopathologic characteristics and oncologic outcomes of patients with ypT0 rectal cancer after preoperative chemoradiotherapy and curative radical surgery.

DESIGN AND SETTINGS

This was a retrospective review of factors influencing outcome of patients treated with preoperative chemoradiotherapy for rectal cancer at a tertiary care university medical center in Seoul, Korea between 2000 and 2008.

PATIENTS

A total of 830 rectal cancer patients underwent surgery after preoperative chemoradiotherapy. Patients were included in the study if they had a pretreatment clinical classification of T3-4 or N+ (or T2N0 and preoperative chemoradiotherapy for sphincter preservation) and if they were classified on pathologic examination as ypT0 after preoperative CRT and curative radical surgery. Patients were classified as.

MAIN OUTCOME MEASURES

Overall survival and disease-free survival were evaluated in relation to ypT0N0 or ypT0N1-2 status and other factors that might influence outcome.

RESULTS

Of 91 patients included in the study, 54 (59.3%) were men; the mean patient age was 55 (SD, 11) years, and mean follow-up duration was 44 (SD, 23) months. Surgical procedures included low anterior resection in 68 patients, abdominoperineal resection in 21, and intersphincteric resection in 2. Mean tumor distance from the anal verge was 4.7 (SD, 1.8) cm. Of the 91 patients, 85 were classified as ypT0N0 and 6 as ypT0N1-2. No patient experienced local recurrence. A total of 11 patients (12.1%) had distant metastases, after a mean 11.1 months, including 7 (8.2%) with ypT0N0 and 4 (66.7%) with ypT0N1-2 tumors. One patient with ypT0N0 and 2 patients with ypT0N1-2 tumors died of metastasis. In patients classified as ypT0N0, the 5-year disease free survival and overall survival rates were 82.3% and 89.2%, respectively. Multivariate analysis showed that ypN1-2 status (p = 0.001) was a significant independent risk factor for recurrence (decreased 5-year disease-free survival), but no factor was associated with 5-year overall survival.

LIMITATIONS

The study is limited by its retrospective nature.

CONCLUSION

Oncologic outcomes in patients with ypT0N0 rectal cancer were excellent. The presence of residual cancer cells in mesorectal lymph nodes represents a risk factor for distant metastasis.