Total Neoadjuvant Therapy: A Shifting Paradigm in Locally Advanced Rectal Cancer Management

ALLIANCE A022104/NRG-GI010: The Janus Rectal Cancer Trial: a randomized phase II/III trial testing the efficacy of triplet versus doublet chemotherapy regarding clinical complete response and disease-free survival in patients with locally advanced rectal cancer

Background

Recent data have demonstrated that in locally advanced rectal cancer (LARC), a total neoadjuvant therapy (TNT) approach improves compliance with chemotherapy and increases rates of tumor response compared to neoadjuvant chemoradiation (CRT) alone. They further indicate that the optimal sequencing of TNT involves consolidation (rather than induction) chemotherapy to optimize complete response rates. Data, largely from retrospective studies, have also shown that patients with clinical complete response (cCR) after neoadjuvant therapy may be managed safely with the watch and wait approach (WW) instead of preemptive total mesorectal resection (TME). However, the optimal consolidation chemotherapy regimen to achieve cCR has not been established, and a randomized clinical trial has not robustly evaluated cCR as a primary endpoint. Collaborating with a multidisciplinary oncology team and patient groups, we designed this NCI-sponsored study of chemotherapy intensification to address these issues and to drive up cCR rates, to provide opportunity for organ preservation, improve quality of life for patients and improve survival outcomes.

Methods

In this NCI-sponsored multi-group randomized, seamless phase II/III trial (1:1), up to 760 patients with LARC, T4N0, any T with node positive disease (any T, N+) or T3N0 requiring abdominoperineal resection or coloanal anastomosis and distal margin within 12 cm of anal verge will be enrolled. Stratification factors include tumor stage (T4 vs T1-3), nodal stage (N+ vs N0) and distance from anal verge (0-4; 4-8; 8-12 cm). Patients will be randomized to receive neoadjuvant long course chemoradiation (LCRT) followed by consolidation doublet (mFOLFOX6 or CAPOX) or triplet chemotherapy (mFOLFIRINOX) for 3-4 months. LCRT in both arms involves 4500 cGy in 25 fractions over 5 weeks + 900 cGy boost in 5 fractions with a fluoropyrimidine (capecitabine preferred). Patients will undergo assessment 8-12 (+/- 4) weeks post-TNT completion. The primary endpoint for the phase II portion will compare cCR between treatment arms. A total number of 296 evaluable patients (148 per arm) will provide statistical power of 90.5% to detect an 17% increase in cCR rate, at a one-sided alpha=0.048. The primary endpoint for the phase III portion will compare disease-free survival (DFS) between treatment arms. A total of 285 DFS events will provide 85% power to detect an effect size of hazard ratio 0.70 at a one-sided alpha of 0.025, requiring enrollment of 760 patients (380 per arm). Secondary objectives include time-to event outcomes (overall survival, organ preservation time and time to distant metastasis) and adverse effects. Biospecimens including archival tumor tissue, plasma and buffy coat in EDTA tubes, and serial rectal MRIs will be collected for exploratory correlative research. This study, activated in late 2022, is open across the NCTN and has a current accrual of 312. Support: U10CA180821, U10CA180882, U24 CA196171; https://acknowledgments.alliancefound.org .

Discussion

Building off of data from modern day rectal cancer trials and patient input from national advocacy groups, we have designed the current trial studying chemotherapy intensification via a consolidation chemotherapy approach with the intent to enhance cCR and DFS rates, increase organ preservation rates, and improve quality of life for patients with rectal cancer.

Trial Registration

Clinicaltrials.gov ID: NCT05610163 ; Support includes U10CA180868 (NRG) and U10CA180888 (SWOG).

Surgical Outcomes in Total Neoadjuvant Therapy for Rectal Cancer Versus Standard Long-course Chemoradiation: A Systematic Review and Meta-analysis of Randomized Controlled Trials

OBJECTIVE

This systematic review and meta-analysis seeks to evaluate the impact of total neoadjuvant therapy (TNT) for rectal cancers on surgical complications and surgical pathology when compared with standard long-course chemoradiotherapy (LCRT).

BACKGROUND

The oncological benefits of TNT are well published in previous meta-analyses, but there is little synthesized information on how it affects surgical outcomes. A recent study has suggested an increase in local recurrence and higher rates of breached total mesorectal excision (TME) plane in TNT patients.

METHODS

This study conformed to the PRISMA (Preferred Reporting Items for Systematic Reviews and Meta-Analyses) guidelines. A search was performed in Medline (via PubMed), Cochrane databases, EMBASE and CINAHL to identify relevant randomized controlled trials (RCTs) comparing outcomes between TNT and LCRT. Meta-analyses of pooled proportions between TNT and LCRT were performed, comparing primary outcomes of surgical mortality, morbidity and all reported complications; surgical-pathology differences, namely mesorectal quality, R0 resection rates, circumferential resection margin positive rates, and sphincter preservation rates. Death and progression of disease during neoadjuvant treatment period was also compared. Risk of bias of RCTs was performed using the Cochrane risk-of-bias tool by 2 independent reviewers.

RESULTS

A total of 3185 patients with rectal cancer from 11 RCTs were included in the analysis: 1607 received TNT and 1578 received LCRT, of which 1422 (TNT arm) and 1391 (LCRT arm) underwent surgical resection with curative intent. There was no significant difference in mortality [risk ratio (RR)=0.86, 95% CI: 0.13-5.52, P =0.88, I2 =52%] or major complications (RR=1.04, 95% CI: 0.86-1.26, P =0.70, I2 =0%) between TNT and LCRT. There was a significantly higher risk of breached TME in TNT group on pooled analysis (RR=1.49, 95% CI: 1.03-12.16, P =0.03, I2 =0%), and on subgroup analysis there is higher risk of breached TME in those receiving extended duration of neoadjuvant treatment (>17 weeks from start of treatment to surgery) when compared with LCRT (RR=1.61, 95% CI: 1.06-2.44, P =0.03). No difference in R0 resection rates (RR=0.85, 95% CI: 0.66-1.10, P =0.21, I2 =15%), circumferential resection margin positive rates (RR=0.87, 95% CI: 0.65-1.16, P =0.35, I2 =10%) or sphincter preservation rates (RR=1.02, 95% CI: 0.83-1.25, P =0.88, I2 =57%) were observed. There was a significantly lower risk of progression of disease to an unresectable stage during the neoadjuvant treatment period in TNT patients (RR=0.60, 95% CI: 0.39-0.92, P =0.03, I2 =18%). On subgroup analysis, it appears to favor those receiving extended duration of neoadjuvant treatment (RR=0.44, 95% CI: 0.26-0.80, P =0.002), and those receiving induction-type chemotherapy in TNT (RR=0.25, 95% CI: 0.07-0.88, P =0.03).

CONCLUSIONS

TNT increases rates of breached TME which can contribute to higher local recurrence rates. TNT, however, improves systemic control by reducing early progression of disease during neoadjuvant treatment period. Further research is warranted to identify patients that will benefit from this strategy.

Do treated rectal tumors appear differently on MRI after chemotherapy versus chemoradiotherapy?

PURPOSE

Increasing studies have focused on neoadjuvant chemotherapy (NCT) in rectal cancer. However, few studies explored the differences in radiographic variation between patients treated with NCT and neoadjuvant chemoradiotherapy (NCRT).

METHODS

Stage II/III rectal cancer patients from March 2016 to December 2019 meeting the criteria treated with NCRT or NCT were included. MRI features, including tumor location, longitudinal length, DWI signal, MRI tumor regression grade (mrTRG), and radiomic texture features, before and after neoadjuvant treatments were reviewed.

RESULTS

116 patients with NCRT and 61 with NCT were analyzed. Among these patients, 46 patients in the NCRT group and 18 in the NCT group were responders with pathological TRG0-1. Within these responders, the mean tumor longitudinal length regression rate (TLRR) of the NCT group was 60.08 ± 11.17%, which was significantly higher than the 50.73 ± 15.28% of the NCRT group (p = 0.010). The proportion of high signal in the DWI image after NCT was higher than that of the NCRT group (88.89% vs 50.00%, p = 0.004). NCT responders had significantly higher median change rates than those of NCRT responders in 11 radiomic features, especially those shape features.

CONCLUSION

MRI images change differently between responders treated with NCRT and those with NCT in rectal cancer. The tumor volumetry and some radiomic features change more obviously in NCT responders, and the tumor signal changes more obviously in NCRT responders. During the evaluation of the response of the tumor to the neoadjuvant treatments, images of patients should be treated differently.

miR-135b Aggravates Fusobacterium nucleatum-Induced Cisplatin Resistance in Colorectal Cancer by Targeting KLF13

Cisplatin resistance is the main cause of colorectal cancer (CRC) treatment failure, and the cause has been reported to be related to Fusobacterium nucleatum (Fn) infection. In this study, we explored the role of Fn in regulating cisplatin resistance of CRC cells and its underlying mechanism involved. The mRNA and protein expressions were examined by qRT-PCR and western blot. Cell proliferation and cell apoptosis were assessed using CCK8 and flow cytometry assays, respectively. Dual-luciferase reporter gene assay was adopted to analyze the molecular interactions. Herein, our results revealed that Fn abundance and miR-135b expression were markedly elevated in CRC tissues, with a favorable association between the two. Moreover, Fn infection could increase miR-135b expression via a concentration-dependent manner, and it also enhanced cell proliferation but reduced apoptosis and cisplatin sensitivity by upregulating miR-135b. Moreover, KLF13 was proved as a downstream target of miR-135b, of which overexpression greatly diminished the promoting effect of miR-135b or Fn-mediated cisplatin resistance in CRC cells. In addition, it was observed that upstream 2.5 kb fragment of miR-135b promoter could be interacted by β-catenin/TCF4 complex, which was proved as an effector signaling of Fn. LF3, a blocker of β-catenin/TCF4 complex, was confirmed to diminish the promoting role of Fn on miR-135b expression. Thus, it could be concluded that Fn activated miR-135b expression through TCF4/β-catenin complex, thereby inhibiting KLF13 expression and promoting cisplatin resistance in CRC.

Exploration of Malignant Characteristics in Neoadjuvant Chemotherapy-Resistant Rectal Cancer, Focusing on Extramural Lesions

BACKGROUND

Extramural vascular invasion (EMVI) and tumor deposits (TD) are poor prognostic factors in rectal cancer (RC), especially when resistant to neoadjuvant chemotherapy (NAC). We aimed to define differential expression in NAC responders and non-responders with concomitant EMVI and TD.

METHODS

From 52 RC surgical patients, post-NAC resected specimens were extracted, comprising two groups: cases with residual EMVI and TD (NAC-resistant) and cases without (NAC-effective). Proteomic analysis was conducted to define differential protein expression in the two groups. To validate the findings, immunohistochemistry was performed in another cohort that included 58 RC surgical patients. Based on the findings, chemosensitivity and prognosis were compared.

RESULTS

The NAC-resistant group was associated with a lower 3-year disease-free survival rate than the NAC-effective group (p = 0.041). Discriminative proteins in the NAC-resistant group were highly associated with the sulfur metabolism pathway. Among these pathway constituents, selenium-binding protein 1 (SELENBP1) expression in the NAC-resistant group decreased to less than one-third of that of the NAC-effective group. Immunohistochemistry in another RC cohort consistently validated the relationship between decreased SELENBP1 and poorer NAC sensitivity, in both pre-NAC biopsy and post-NAC surgery specimens. Furthermore, decrease in SELENBP1 was associated with a lower 3-year disease-free survival rate (p = 0.047).

CONCLUSIONS

We defined one of the differentially expressed proteins in NAC responders and non-responders, concomitant with EMVI and TD. SELENBP1 was suspected to contribute to NAC resistance and poor prognosis in RC.

The impact of adjuvant chemotherapy on survival in mucinous and non-mucinous rectal adenocarcinoma patients after TME surgery

INTRODUCTION

The value of adjuvant chemotherapy for rectal cancer patients is debated and varies in different subgroups. One such subgroup is mucinous adenocarcinoma (MAC), which is more treatment resistant compared to non-mucinous adenocarcinoma (NMAC). To date, mucinous histology is not taken into account when deciding on adjuvant treatment strategy. This is the first study to exclusively include patients with rectal cancer, then separate MAC and NMAC and compare the survival in patients that had or did not have adjuvant chemotherapy.

MATERIAL AND METHODS

The study included retrospective register data from 365 Swedish patients with stage II-IV rectal adenocarcinoma, 56 patients with MAC and 309 patients with NMAC. All patients were considered curative, had surgery with total mesorectal excision in 2004-2013, and were followed up until death or 2021.

RESULTS

Patients with MAC that had adjuvant chemotherapy had better overall survival (OS, HR 0.42; CI 95%: 0.19-0.93; p = 0.032) and a trend towards better cancer-specific survival (CSS, HR 0.41 CI 95%: 0.17-1.03; p = 0.057) compared to patients without chemotherapy (HR 0.42; CI 95%: 0.19-0.93; p = 0.032). The difference in OS was still significant even after adjusting for sex, age, stage, differentiation, neoadjuvant chemotherapy and preoperative radiotherapy (HR 0.40; CI 95%: 0.17-0.92; p = 0.031). There was no such difference in the NMAC patients except in the stage-by-stage subgroup analyses where patients in stage IV had better survival after adjuvant chemotherapy.

CONCLUSIONS

There may be a difference in treatment response to adjuvant chemotherapy between MAC and NMAC patients. Patients with MAC could possibly benefit from adjuvant chemotherapy in stages II-IV. Further studies are however needed to confirm these results.

Clinical outcome after total neoadjuvant treatment (CAO/ARO/AIO-12) versus intensified neoadjuvant and adjuvant treatment (CAO/ARO/AIO-04) a comparison between two multicenter randomized phase II/III trials

BACKGROUND

Total neoadjuvant therapy (TNT) can enhance local tumor regression, but its survival benefits compared to intensified chemoradiotherapy (CRT) followed by adjuvant chemotherapy (CT) remain unclear.

METHODS

This is a secondary comparison between 607 patients treated with intensified 5-FU/Oxaliplatin neoadjuvant CRT and adjuvant CT within the experimental arm of the CAO/ARO/AIO-04 phase III trial, and 306 patients treated with TNT within the CAO/ARO/AIO-12 phase II trial. Comparison between clinical-pathological characteristics, surgical quality, and post-surgical complications were analyzed using the Pearson's Chi-squared or Mann-Whitney U test. Oncological outcome was examined with log-rank, Gray's test, and multivariate cox regression. In addition, further subgroup analyses and propensity score matching were performed to optimize the balance of baseline covariates.

FINDINGS

Patients treated with CRT followed by consolidation CT had a significantly higher rate of pathological complete remission (pCR) compared to patients treated within the experimental arm of the CAO/ARO/AIO-04 trial (25.3 % vs 17.3 %, P = 0.04). Post-surgical complications were less common in the CAO/ARO/AIO-12 trial. After a median follow-up of 46 months, clinical outcome did not differ significantly in the overall cohort, in any subgroup or after propensity score matching. In multivariate analysis, disease-free survival (DFS) was similar between the experimental arm of the CAO/ARO/AIO-04 trial and treatments arms of the CAO/ARO/AIO-12 trial (vs arm A: HR 0.92 [95 % CI 0.62-1.37], P = 0.69; vs arm B: HR 1.06 [95 % CI 0.72-1.58], P = 0.76).

INTERPRETATION

Notwithstanding the limitations of intertrial comparison, TNT did not improve long term oncological outcome in our study compared to the intensified neoadjuvant CRT and adjuvant CT treatment in the CAO/ARO/AIO-04 trial. Improved response rates after TNT offers an attractive option to explore organ preservation in selective patients with locally advanced rectal cancer.

Changing patterns of neoadjuvant therapy for locally advanced rectal cancer: A narrative review

Standard treatment for patients with locally advanced rectal cancer has been the multidisciplinary approach of neoadjuvant chemoradiotherapy, followed by total mesorectal excision (TME) and postoperative adjuvant chemotherapy. This reduces the local recurrence rate, but the challenge of distant metastasis still persists. The improvement in treatment approach has always been the focus of clinical research and studies have been conducted worldwide in recent years. On one hand, evidence suggests that increasing the intensity of treatment can result in better tumor regression, for example by adding a second drug to the neoadjuvant chemoradiotherapy, or extending the interval between neoadjuvant therapy and surgery, or incorporating chemotherapy and chemoradiotherapy in the neoadjuvant setting. On the other hand, neoadjuvant immunotherapy and selective omission of neoadjuvant radiotherapy may improve the quality of life of patients. In this article, we review the key clinical research progresses in neoadjuvant therapy for locally advanced rectal cancer, hoping to provide some valuable views on the individualized treatment for rectal cancer.

The role of neo-adjuvant therapy in cholangiocarcinoma: A systematic review

Introduction

Cholangiocarcinoma (CCA) is the most common malignancy affecting the biliary tree. The only curative treatment is surgical resection, aiming for negative margins (R0). For those who have locally advanced disease, which is borderline resectable, neoadjuvant chemoradiation presents an opportunity to reduce tumour size and allow for surgical resection. The aim of this review is to establish the role of neoadjuvant therapy in each subtype of CCA and establish its impact on survival.

Methods

Search terms such as 'neoadjuvant therapy' and 'cholangiocarcinoma' were searched on multiple databases, including Pubmed, Ovid and Embase. They were then reviewed separately by two reviewers for inclusion criteria. 978 studies were initially identified from the search strategy, with 21 being included in this review.

Results

5,009 patients were included across 21 studies. 1,173 underwent neoadjuvant therapy, 3,818 had surgical resection alone. 359 patients received Gemcitabine based regimes, making it the most commonly utilised regimen for patients CCA and Biliary Tract Cancer (BTC). Data on tolerability of regimes was limited. All included papers were found to have low risk of bias when assessed using The Newcastle Ottawa Scale. Patients who underwent neoadjuvant therapy had a similar median overall survival compared to those who underwent upfront surgery (38.4 versus 35.1 months respectively). Pre-operative CA19-9, microvascular invasion, perineurial invasion and positive lymph nodes were of prognostic significance across BTC and CCA subtypes.

Conclusion

Neoadjuvant therapy and surgical resection is associated with improved patient outcomes and longer median overall survival compared to therapy and upfront surgery, however heterogeneity between research papers limited the ability to further analyse the significance of these results. Although initial studies are promising, further research is required in order to define suitable treatment protocols and tolerability of neoadjuvant regimes.

Systematic review registration

https://www.crd.york.ac.uk/prospero/, identifier CRD42020164781.

Outcomes of Locally Advanced Rectal Cancer Patients Treated with Total Neoadjuvant Treatment: A Meta-Anaysis of Randomized Controlled Trials

BACKGROUND & AIMS

Determining outcomes using the total neoadjuvant therapy (TNT) in patients with local advanced rectal cancer is important for stratifying patients according to expected outcomes in future studies in the era of treatment combination. The present meta-analysis estimated the pathological complete response, disease-free survival, and overall survival probabilities of rectal cancer patients and identified predictors of outcomes.

METHODS

Studies reporting pathological complete response rate and time-dependent outcomes (progression or death) after total neoadjuvant treatment of locally advanced rectal cancer (LARC) were identified in MEDLINE through January 2022. Three independent observers extracted data on patient populations and outcomes and combined the data using a distribution-free summary survival curve. The primary outcomes were actuarial probabilities of recurrence and survival.

RESULTS

Fourteen RCTs, including 18 TNT arms, met the inclusion criteria. The pooled estimate of pathological complete response (pCR) probability was 23.6%, with moderate heterogeneity between studies. The pooled estimates of actuarial disease-free survival rate were 70.6% at 3 years and 65.4% at 5 years. The pooled estimates of actuarial survival rates were 93% at 3 years and 81.6% at 5 years. In both these outcomes, heterogeneity between studies was highly significant.

CONCLUSION

This meta-analysis showed that Total Neoadjuvant Therapy is an optimal approach for LARC patients. The results provide a useful benchmark for future comparisons of the benefits of combinations of other drug families as target therapies or immunotherapies.

The watch-and-wait strategy versus radical resection for rectal cancer patients with a good response (≤ycT2) after neoadjuvant chemoradiotherapy

Purpose

This study aims to oncologic outcomes of the watch-and-wait (WW) strategy compared with radical resection (RR).

Methods

Patients with rectal cancer who received neoadjuvant chemoradiotherapy (nCRT) and achieved ≤ycT2 between 2008 and 2016 were included. The mean follow-up time was 61 months (range, 0-168 months). Recurrence-free survival (RFS), local recurrence-free survival (LRFS), distant metastasis-free survival (DMFS), and overall survival (OS) were compared. A total of 446 patients were included, and WW was adopted for 34 patients.

Results

WW patients were older (P = 0.022) and less advanced initial cT stage (P = 0.004). Ten patients in the WW group (29.4%) experienced local regrowth. Later, distant metastases occurred in 7 of these patients. The 5-year RFS (74.1% vs. 79.5%), DMFS (74.1% vs. 81.6%), and OS (90.4% vs. 87.7%) for the WW and RR groups were not statistically different. However, LRFS in the WW group was significantly lower (65.1% vs. 97.0%, P < 0.001). The initial cT stage was associated with RFS (P = 0.019) and LRFS (P = 0.037). WW was an independent risk factor for LRFS (P < 0.001) and DMFS (P = 0.024). After 1:4 propensity score matching between the WW and RR groups, there was no difference in RFS and OS. However, the 5-year LRFS (67.5% vs. 96.5%) and DMFS (73.2% vs. 86.4%) demonstrated a statistically significant difference between the groups.

Conclusion

By appointing the WW strategy, oncologic safety was not ensured. The WW strategy must be implemented with caution in patients with ≤ycT2 stage, particularly those with advanced initial cT stage.

Differences in Surgical Outcomes and Quality-of-Life Outcomes in Pelvic Exenteration Between Locally Advanced Versus Locally Recurrent Rectal Cancers

BACKGROUND

Although pelvic exenteration remains the only curative option for locally advanced rectal cancer and locally recurrent rectal cancer, only limited evidence is available on the differences in surgical and quality-of-life outcomes between the two.

OBJECTIVE

This study aimed to compare surgical outcomes and identify any differences or predictors of quality of life of patients with locally advanced rectal cancer and locally recurrent rectal cancer undergoing pelvic exenteration.

DESIGN

This was a cohort study.

SETTING

This study was conducted at Royal Prince Alfred Hospital, Sydney, Australia.

PATIENTS

This study included patients with locally advanced rectal cancer and locally recurrent rectal cancer who underwent pelvic exenteration between July 2008 and March 2019.

MAIN OUTCOME MEASURES

The main outcome measures included Short Form 36 version 2 and Functional Assessment of Cancer Therapy-Colorectal score.

RESULTS

A total of 271 patients were included in this study. Locally advanced rectal cancer patients had higher rates of R0 resection ( p = 0.003), neoadjuvant chemoradiotherapy ( p < 0.001), and had greater median overall survival (75.1 vs. 45.8 months), although the latter was clinically but not statistically significant. There was a higher blood loss ( p < 0.001), longer length of stay ( p = 0.039), and longer operative time ( p = 0.002) in the locally recurrent rectal cancer group. This group also had a higher mean baseline physical component summary score and Functional Assessment of Cancer Therapy-Colorectal score; however, there were no significant differences in complications or quality-of-life outcomes between with the two groups at any time points postoperatively up to 12 months.

LIMITATION

The study was from a specialized experienced center, which could limit its generalizability.

CONCLUSIONS

Patients with locally recurrent rectal cancer tend to require a more extensive surgery with a longer operative time and more blood loss and longer recovery from surgery, but despite this, their quality of life is comparable to those with locally advanced rectal cancer. See Video Abstract at http://links.lww.com/DCR/B1000 .

DIFERENCIAS EN LOS RESULTADOS QUIRRGICOS Y LOS RESULTADOS DE LA CALIDAD DE VIDA EN LA EXENTERACIN PLVICA ENTRE EL CNCER DE RECTO LOCALMENTE AVANZADO Y EL CNCER DE RECTO LOCALMENTE RECIDIVANTE

ANTECEDENTES:Aunque la exenteración pélvica sigue siendo la única opción curativa para el cáncer de recto localmente avanzado y el cáncer de recto localmente recurrente, solo hay evidencia limitada disponible sobre las diferencias en los resultados quirúrgicos y de calidad de vida entre los dos.OBJETIVO:Este estudio tuvo como objetivo comparar los resultados quirúrgicos e identificar cualquier diferencia o predictor de la calidad de vida de los pacientes con cáncer de recto localmente avanzado y cáncer de recto localmente recurrente sometidos a exenteración pélvica.DISEÑO:Este fue un estudio de cohorte.AJUSTE:Este estudio se realizó en el Royal Prince Alfred Hospital, Sydney, Australia.PACIENTES:Este estudio incluyó pacientes con cáncer de recto localmente avanzado y cáncer de recto localmente recurrente que se sometieron a exenteración pélvica entre julio de 2008 y marzo de 2019.PRINCIPALES MEDIDAS DE RESULTADO:Las principales medidas de resultado incluyeron el formulario corto 36 versión 2 y la puntuación de la evaluación funcional de la terapia del cáncer colorrectal.RESULTADOS:Un total de 271 pacientes fueron incluidos en este estudio. Los pacientes con cáncer de recto localmente avanzado tuvieron tasas más altas de resección R0 ( p = 0,003), quimiorradioterapia neoadyuvante ( p < 0,001) y una mediana de supervivencia general más alta (75,1 frente a 45,8 meses),a pesar de que esta última fue clínica pero no estadísticamente significativa. Hubo una mayor pérdida de sangre ( p < 0,001), una estancia más prolongada ( p = 0,039) y un tiempo operatorio más prolongado ( p = 0,002) en el grupo de cáncer de recto localmente recurrente. También tenían una puntuación de componente físico inicial media más alta y una puntuación de Evaluación funcional de la terapia del cáncer colorrectal; sin embargo, no hubo diferencias significativas en las complicaciones o los resultados de la calidad de vida entre los dos grupos en ningún momento después de la operación hasta los 12 meses.LIMITACIÓN:El estudio fue de un centro especializado con experiencia, lo que podría limitar su generalización.CONCLUSIONES:Los pacientes con cáncer de recto localmente recurrente tienden a requerir una cirugía más extensa con un tiempo operatorio más largo y más pérdida de sangre y una recuperación más prolongada de la cirugía, pero a pesar de esto, su calidad de vida es comparable a aquellos con cáncer de recto localmente avanzado. Consulte Video Resumen en http://links.lww.com/DCR/B1000 . (Traducción-Dr. Yolanda Colorado ).

Total neoadjuvant therapy versus standard therapy in locally advanced rectal cancer: A systematic review and meta-analysis of 15 trials

Background

Neoadjuvant chemoradiotherapy (nCRT) before total mesorectal excision (TME) and followed systemic chemotherapy is widely accepted as the standard therapy for locally advanced rectal cancer (LARC). This meta-analysis was to evaluate the current evidence regarding nCRT in combination with induction or consolidation chemotherapy for rectal cancer in terms of oncological outcomes.

Methods

A systematic search of medical databases (PubMed, EMBASE and Cochrane Library) was conducted up to the end of July 1, 2021. This meta-analysis was performed to evaluate the efficacy of TNT in terms of pathological complete remission (pCR), nCRT or surgical complications, R0 resection, local recurrence, distant metastasis, disease-free survival (DFS) and overall survival (OS) in LARC.

Results

Eight nRCTs and 7 RCTs, including 3579 patients were included in the meta-analysis. The rate of pCR was significantly higher in the TNT group than in the nCRT group, (OR 1.85, 95% CI 1.39–2.46, p < 0.0001), DFS (HR 0.80, 95% CI 0.69–0.92, p = 0.001), OS (HR 0.75, 95% CI 0.62–0.89, p = 0.002), nCRT complications (OR 1.05, 95% CI 0.77–1.44, p = 0.75), surgical complications (OR 1.02, 95% CI 0.83–1.26, p = 0.83), local recurrence (OR 1.82, 95% CI 0.95–3.49, p = 0.07), distant metastasis (OR 0.77, 95% CI 0.58–1.03, p = 0.08) did not differ significantly between the TNT and nCRT groups.

Conclusion

TNT appears to have advantages over standard therapy for LARC in terms of pCR, R0 resection, DFS, and OS, with comparable nCRT and postoperative complications, and no increase in local recurrence and distant metastasis.

Robotic versus laparoscopic low anterior resection following neoadjuvant chemoradiation therapy for stage II-III locally advanced rectal cancer: a single-centre cohort study

Neoadjuvant chemo-radiotherapy (nCRT) of locally advanced rectal cancer is associated with challenging surgical treatment and increased postoperative morbidity. Robotic technology overcomes laparoscopy limitations by enlarged 3D view, improved anatomical transection accuracy, and physiologic tremor reduction. Patients with UICC stage II-III rectal cancer, consecutively referred to our institution between March 2015 and June 2020 (n = 102) were treated with robotic (Rob-G, n = 38) or laparoscopic (Lap-G, n = 64) low anterior resection (LAR) for total meso-rectal excision (TME) following highly standardized and successful nCRT treatment. Feasibility, conversion rates, stoma creation, morbidity and clinical/pathological outcome were comparatively analysed. Sex, age, BMI, ASA scores, cTN stages and tumour distance from dentate line were comparable in the two groups. Robotic resection was always feasible without conversion to open surgery, which was necessary in 11/64 (17%) Lap-G operations (p = 0.006). Primary or secondary stomata were created in 17/38 (45%) Rob-G and 52/64 (81%) Lap-G patients (p < 0.001). Major morbidity occurred in 7/38 (18.4%) Rob-G and 6/64 (9.3%) Lap-G patients (p = 0.225). Although median operation time was longer in Rob-G compared with Lap-G (376; IQR: 330-417 min vs. 300; IQR: 270-358 min; p < 0.001), the difference was not significant in patients (Rob-G, n = 6; Lap-G, n = 10) with ≥30 BMI (p = 0.106). Number of resected lymph nodes, ypTN staging and circumferential resection margins (CRM) were comparable. Resection was complete in 87% of Rob-G and 89% of Lap-G patients (p = 0.750). Robotic LAR is not inferior to laparoscopic LAR following nCRT. Larger, randomized studies are needed to confirm lower conversion in robotic, compared to laparoscopic resection.

Laparoscopic Versus Open Surgery for Locally Advanced Rectal Cancer: Five-Year Survival Outcomes in a Large, Multicenter, Propensity Score-Matched Cohort Study

BACKGROUND

There is a paucity of evidence pertaining to long-term survival outcomes of laparoscopic versus open surgery for locally advanced rectal cancer.

OBJECTIVE

This study aimed to evaluate the long-term survival outcomes of laparoscopic surgery for locally advanced rectal cancer and to investigate the recurrence pattern.

DESIGN

This was a prospective analysis of a registered cohort.

SETTINGS

This study was conducted at 69 institutions across Japan.

PATIENTS

A total of 1500 patients with clinical stage II-III rectal cancer located below the peritoneal reflection between January 2010 and December 2011 were included. After propensity score matching, all eligible patients, including the matched patients registered in 2014, were prospectively followed up.

MAIN OUTCOME MEASURES

Five-year relapse-free survival was the primary outcome.

RESULTS

The median follow-up period was 5.6 years. Among the 964 matched patients, the 5-year relapse-free survival was 65.1% in the open group versus 63.5% in the laparoscopic group (HR 1.04; p = 0.71). Distant recurrences at rare sites, which were more frequently observed in the laparoscopic group, were significantly less salvaged (adjusted OR 0.74; p = 0.045). Postrecurrence 5-year overall survival was significantly better for patients who underwent salvage surgery than for those who did not; 55.3% vs 29.5% for patients with initial local recurrence ( p = 0.03) and 64.4% vs 30.7% for patients with distant recurrence alone ( p < 0.001).

LIMITATIONS

Potential heterogeneity and influence of unknown confounding.

CONCLUSIONS

Five-year follow-up data demonstrated that laparoscopic surgery for locally advanced rectal cancer was safely performed in terms of long-term prognosis. In addition, salvage surgery for recurrent lesions was associated with prolonged postrecurrence survival, both in patients with local and distant recurrence. However, recurrence at rare sites may require further investigation. See Video Abstract at http://links.lww.com/DCR/B793 .

CIRUGA LAPAROSCPICA VERSUS CIRUGA ABIERTA EN CNCER DE RECTO LOCALMENTE AVANZADO RESULTADOS DE SUPERVIVENCIA A CINCO AOS EN UN ESTUDIO DE COHORTE DE GRAN MAGNITUD, MULTICNTRICO Y DE PAREAMIENTO POR PUNTAJE DE PROPENSIN

ANTECEDENTES:Existe una escasez de pruebas relacionadas con los resultados de supervivencia a largo plazo de la cirugía laparoscópica versus abierta para el cáncer de recto localmente avanzado.OBJETIVO:Este estudio tuvo como objetivo evaluar los resultados de supervivencia a largo plazo de la cirugía laparoscópica para el cáncer de recto localmente avanzado e investigar el patrón de recurrencia.DISEÑO:Fue un análisis prospectivo de una cohorte registrada.ENTORNO CLÍNICO:El estudio se llevó a cabo en 69 instituciones en todo Japón.PACIENTES:Se incluyó un total de 1500 pacientes con cáncer de recto en estadio clínico II-III ubicados por debajo de la reflección peritoneal, entre enero del 2010 y diciembre del 2011. Después del pareamiento por puntaje de propensión, se realizó un seguimiento prospectivo de todos los pacientes elegibles, incluidos los pacientes emparejados registrados en 2014.PRINCIPALES MEDIDAS DE VALORACIÓN:La supervivencia sin recaídas a cinco años fue el resultado primario.RESULTADOS:El período de seguimiento medio fue de 5,6 años. Entre los 964 pacientes emparejados, la supervivencia libre de recaída a 5 años fue del 65,1% en el grupo abierto frente al 63,5% en el grupo laparoscópico (cociente de riesgo 1,04; p = 0,71). Las recurrencias a distancia en sitios raros, que se observaron con mayor frecuencia en el grupo laparoscópico, tuvieron menor sobrevida (razón de posibilidades ajustada 0,74; p = 0,045). La supervivencia general a los 5 años después de la recidiva fue significativamente menor en los pacientes sometidos a una cirugía de rescate; 55,3% frente al 29,5% para los pacientes con recidiva local inicial ( p = 0,03) y 64,4% frente al 30,7% para los pacientes con recidiva a distancia sola ( p < 0,001).LIMITACIONES:Potencial heterogeneidad e influencia de factores de confusión desconocidos.CONCLUSIONES:El seguimiento a cinco años demostró que la cirugía laparoscópica para el cáncer de recto localmente avanzado es segura en términos de pronóstico a largo plazo. Además, la cirugía de rescate de las lesiones recurrentes se asoció con una mayor supervivencia posrecurrencia, tanto en pacientes con recurrencia local como a distancia. Sin embargo, la recurrencia en sitios raros puede requerir una mayor investigación. Consulte Video Resumen en http://links.lww.com/DCR/B793 . (Traducción- Dr. Ingrid Melo ).

Nonoperative versus Operative Approach According to the Response to Neoadjuvant Chemoradiotherapy for Rectal Cancer: A Prospective Cohort Study

•

Watch-and-wait patients after chemoradiotherapy for rectal cancer have good functional outcome.

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No survival differences were seen between patients undergoing surgery versus patients in a watch-and-wait protocol.

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There is a subset of patients that has initial favorable response but will recur with distant metastases afterwards.

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A previously published model predicting (near)-complete response could not be validated.

Purpose

To report on organ preservation following chemoradiotherapy (CRT) in a prospective cohort of locally advanced rectal cancer patients.

Methods and materials

Fifty-two patients received CRT. MRI and ¹⁸F-FDG-PET/CT were performed prior to CRT. Response assessment was done 6 and 12 weeks after CRT using digital rectal examination, MRI, ¹⁸F-FDG-PET/CT and endoscopy. For clinical complete response or minimal residual disease, a watch-and-wait (W&W) protocol was started.

Regrowth-free survival (ReFS), Total Mesorectal Excision-free disease-free survival, distant metastasis-free survival (DMFS) and overall survival (OS) were evaluated using Kaplan-Meier method. Functional outcome was compared with the Wilcoxon signed-rank test using EORTC QLQ-C30, MSKCC BFI, LARS and IIEF-5/FSFI-5 questionnaires. A previously developed prediction model performance was tested using receiver operating characteristic analysis.

Results

29/52 patients entered a W&W protocol. There was no difference in two-year DMFS (81.1 % vs 78.8 %, p = 0.82), two-year OS (96.4 % vs 100 %, p = 0.38) and two-year DFS (77.5 % vs 78.8 %, p = 0.87) between W&W patients and those who underwent surgery at 12 weeks after CRT. Two-year DMFS differed between W&W with local regrowth, W&W with sustained response and patients who had surgery (66.7 % vs 88.0 % vs 78.8 %; p = 0.04). At 6 and 12 months, W&W patients reported good QoL and bowel function. The model validation reached an AUC of 0.627.

Conclusion

Good functional outcome in patients with rectal cancer allocated to surveillance after CRT needs to be balanced against potentially worse DMFS in a subset of patients without sustained clinical complete response. Reliable prediction of patients eligible for surveillance programs needs further investigation.

Acellular mucin in lymph nodes isolated from treatment-naïve colorectal cancer resections: a clinicopathologic analysis of 16 cases

Lymph nodes with acellular mucin harvested from treated colorectal cancers (CRC) are staged as pN0. However, there is variability among pathologists while reporting the pN stage when acellular mucin is found within nodes of untreated CRCs. While the UICC guidelines suggest staging them as pN1, the AJCC and CAP do not offer any recommendations. In order to characterize their clinicopathologic features and outcome, we compared 16 untreated CRCs (study group; mean age: 68 years) harboring nodes with acellular mucin with 34 pN0 and 25 pN1 untreated CRC controls. All tumors were unifocal; 12 (75%) were right-sided lesions. Most cases (75%) showed one node with acellular mucin (range: 1-3). MMR-deficient tumors were significantly more common in the study group (83%) compared to pN0 (33%; p = 0.006) and pN1 controls (8%; p < 0.001). The overall survival of study group patients was closer to pN0 compared to pN1 controls; however, this difference was not statistically significant. In conclusion, untreated CRC that harbor acellular mucin within lymph nodes commonly present as right-sided, MMR-deficient tumors in older women that show a non-mucinous phenotype. While the limited number of cases precludes us from making any formal recommendations about staging, we suggest that the finding of acellular mucin in a node should prompt evaluation of deeper levels (with or without cytokeratin immunohistochemistry) and submission of all pericolonic fat for additional lymph node harvest. Whether acellular mucin in nodes of untreated CRCs is related to the indolent biology of the disease, a robust local immune response or MMR deficiency requires further investigation.

Circular RNA circLRCH3 Inhibits Proliferation, Migration, and Invasion of Colorectal Cancer Cells Through miRNA-223/LPP Axis

Purpose

Colorectal cancer (CRC) is one of the most common carcinomas worldwide with a high mortality rate. Numerous studies suggest that circular RNA (circRNA) plays a crucial role in the progression of various carcinomas, including CRC. The present work focused on exploring the role and underlying molecular mechanism of action of the circRNA circLRCH3 in CRC.

Methods

Real-time reverse transcription-quantitative polymerase chain reaction (RT-qPCR) was conducted to detect expression levels of circLRCH3, miR-233, and lipoma preferred partner (LPP). The 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay was used to measure the proliferation of CRC cells and the transwell assay was used to evaluate cell migration and invasion capacity. A flow cytometry assay was used to analyze the effect of circLRCH3 on the distribution of the cell cycle and apoptosis of CRC cells. The expression of LPP was analyzed using Western blotting or an RT-qPCR assay. The relationship between miR-223 and circLRCH3, and that between miR-223 and LPP, was predicted and examined using bioinformatics analysis and luciferase reporter gene experiments. A xenograft tumor formation assay was also performed.

Results

We found that the expression level of circLRCH3 was downregulated in CRC cells and negatively correlated with miR-223. The overexpression of circLRCH3 or silencing of miR-223 inhibited the growth, invasion, and migration of CRC cells, but promoted their apoptosis. In contrast, overexpression of miR-223 and depletion of LPP severally abrogated the tumor suppressive roles of circLRCH3 and miR-223 knockdown in CRC cells in vitro. The xenograft experiments in nude mice also proved the antitumor effect of circLRCH3.

Conclusion

These results suggested that the circLRCH3/miR-223/LPP axis likely plays a critical role in CRC.

Long non-coding RNA FEZF1-AS1 promotes rectal cancer progression by competitively binding miR-632 with FAM83A

The long non-coding RNA (lncRNA) forebrain embryonic zinc finger protein 1 antisense RNA1 (FEZF1-AS1) was recently identified as an oncogenic gene in several types of tumors. The biological function of FEZF1-AS1 in rectal cancer progression, however, remains unknown. In the present study, we discover that FEZF1-AS1 is significantly upregulated in rectal cancer tissues and cells. Knocking down of FEZF1-AS1 suppresses cell proliferation, migration, and invasion , and tumorigenesis . Furthermore, FEZF1-AS1 functions as a competing endogenous RNA (ceRNA) for miR-632, resulting in the suppression of family with sequence similarity 83, member A (FAM83A). Overall, our findings reveal that FEZF1-AS1/miR-632/FAM83A axis plays an oncogenic role in rectal cancer progression, suggesting that it may be a novel therapeutic target for rectal cancer.

[Complete response after neoadjuvant therapy of rectal cancer: implications for surgery]

For (locally advanced) rectal cancer, a multimodal therapy concept comprising neoadjuvant radiotherapy/chemoradiotherapy, radical surgical resection with partial/complete mesorectal excision and subsequent adjuvant chemotherapy represents the current international standard of care. Further developments in neoadjuvant therapy concepts, such as the principle of total neoadjuvant therapy, lead to an increasing number of patients who show a complete clinical response in restaging after neoadjuvant therapy without clinically detectable residual tumor. In view of the risk associated with radical surgical resection in terms of perioperative morbidity and a potentially non-continence-preserving procedure, the question of the oncological justifiability of an organ-preserving procedure in the case of a complete clinical response under neoadjuvant therapy is increasingly being raised. The therapeutic principle of watch and wait, defined by refraining from immediate radical surgical resection and inclusion in a close-meshed, structured follow-up program, currently appears to be oncologically justifiable based on the current study situation; however, for the initial evaluation of the extent of the clinical response and for the structuring of the close-meshed follow-up program, further optimization and standardization based on broadly designed studies appear necessary in order to be able to provide this concept to a clearly defined patient collective as an oncologically equivalent therapy principle also outside specialized centers.

Radiation boost for synchronous solitary inguinal lymph node metastasis during neoadjuvant chemoradiotherapy for locally advanced rectal cancer

BACKGROUND

Some patients with locally advanced rectal cancer (LARC) present with inguinal lymph node metastases without evidence of other systemic disease, known as solitary inguinal lymph node metastasis (SILNM). These patients may represent a distinct subset who have a more favorable prognosis and should be treated with curative intent. The optimal treatment strategy for these patients has not been determined.

METHODS

We retrospectively reviewed 16 consecutive LARC patients diagnosed between January 2017 and December 2019, who had SILNM, were treated with an inguinal lymph nodes (ILN) radiation boost with curative intent during neoadjuvant chemoradiotherapy (nCRT) and underwent total mesorectal excision (TME). We used Kaplan-Meier survival curves to calculate survival rates, and recorded radiation-related toxicity.

RESULTS

None of these 16 patients developed pelvic or inguinal recurrences, and 3 of the patients developed distant metastases. The 3-year overall survival rate and locoregional relapse-free survival rate were both 100%. The 3-year disease-free rate and distant metastasis-free survival rate were both 81.3%. Of 5 patients who had ILN dissection for suspicious ILNs after neoadjuvant treatment, 2 had residual nodal tumor confirmed. Grade 3 toxicity was found in 5 patients, and no patients had lymphedema or other grade 4 or 5 toxicities.

CONCLUSIONS

In LARC patients with synchronous SILNM, a radiation boost to the ILNs during nCRT achieved excellent local control with acceptable toxicity. Though the optimal treatment strategy remains unclear, nCRT with an ILN radiation boost prior to TME may be a reasonable therapeutic approach to consider for this subset of patients.

The effects of neoadjuvant chemoradiotherapy and an in-hospital exercise training programme on physical fitness and quality of life in locally advanced rectal cancer patients: a randomised controlled trial (The EMPOWER Trial)

BACKGROUND

The EMPOWER trial aimed to assess the effects of a 9-week exercise prehabilitation programme on physical fitness compared with a usual care control group. Secondary aims were to investigate the effect of (1) the exercise prehabilitation programme on psychological health; and (2) neoadjuvant chemoradiotherapy (NCRT) on physical fitness and psychological health.

METHODS

Between October 2013 and December 2016, adults with locally advanced rectal cancer undergoing standardised NCRT and surgery were recruited to a multi-centre trial. Patients underwent cardiopulmonary exercise testing (CPET) and completed HRQoL questionnaires (EORTC-QLQ-C30 and EQ-5D-5L) pre-NCRT and post-NCRT (week 0/baseline). At week 0, patients were randomised to exercise prehabilitation or usual care (no intervention). CPET and HRQoL questionnaires were assessed at week 0, 3, 6 and 9, whilst semi-structured interviews were assessed at week 0 and week 9. Changes in oxygen uptake at anaerobic threshold (VO2 at AT (ml kg-1 min-1)) between groups were compared using linear mixed modelling.

RESULTS

Thirty-eight patients were recruited, mean age 64 (10.4) years. Of the 38 patients, 33 were randomised: 16 to usual care and 17 to exercise prehabilitation (26 males and 7 females). Exercise prehabilitation significantly improved VO2 at AT at week 9 compared to the usual care. The change from baseline to week 9, when adjusted for baseline, between the randomised groups was + 2.9 ml kg -1 min -1; (95% CI 0.8 to 5.1), p = 0.011.

CONCLUSION

A 9-week exercise prehabilitation programme significantly improved fitness following NCRT. These findings have informed the WesFit trial (NCT03509428) which is investigating the effects of community-based multimodal prehabilitation before cancer surgery.

TRIAL REGISTRATION

ClinicalTrials.gov NCT01914068 . Registered 1 August 2013.

Oncologic and survival outcomes in elderly patients with locally advanced rectal cancer receiving neoadjuvant chemoradiotherapy and total mesorectal excision

BACKGROUND

The efficacy of the addition of neoadjuvant chemotherapy to neoadjuvant chemoradiotherapy and total mesorectal excision for locally advanced rectal cancer in elderly patients has not been established.

METHODS

A total of 3096 locally advanced rectal cancer patients who received neoadjuvant chemotherapy, along with neoadjuvant chemoradiotherapy and total mesorectal excision, with or without adjuvant chemotherapy, between January 2010 and December 2018, were studied retrospectively. Patients were divided into elderly (>75 years) and younger (≤75 years) groups, and propensity score matching was used to balance a potentially confounding clinical bias. Overall survival, cancer-specific survival, disease-free survival, distant metastasis-free survival and local recurrence-free survival rates for the two groups were compared. Hazard ratios (HR) with 95% confidence intervals (CI) for different clinicopathological variables were calculated to determine predictors of 3-year overall survival.

RESULTS

Mean follow-up was 39.0 (range, 5-140) months. The overall 3-year overall survival, cancer-specific survival, disease-free survival, distant metastasis-free survival and locoregional relapse-free survival rates were 86.1, 87.6, 80.0, 82.4 and 95.4%, respectively. Only 3-year overall survival rates differed significantly between the elderly (77.2%) and younger (88.9%) groups (P = 0.01). Cancer-specific survival, disease-free survival, distant metastasis-free survival and locoregional relapse-free survival rates did not differ significantly between the two groups. Significant negative independent prognostic factors for 3-year overall survival were age >75 years (HR = 2.016, 95% CI 1.157-23.511, P = 0.01) and high pathologic TNM stage (yp stage III, P < 0.001).

CONCLUSION

For elderly locally advanced rectal cancer patients who have good health and performance status, the addition of neoadjuvant chemotherapy to neoadjuvant chemoradiotherapy and total mesorectal excision can result in disease-related survival rates and oncological outcomes similar to those experienced by younger patients. The decision to use this treatment approach in elderly patients should not be based solely on chronological age.

Molecular and Dynamic Evaluation of Proteins Related to Resistance to Neoadjuvant Treatment with Chemoradiotherapy in Circulating Tumor Cells of Patients with Locally Advanced Rectal Cancer

The heterogeneity of response to neoadjuvant chemoradiotherapy (NCRT) is still a challenge in locally advanced rectal cancer (LARC). The evaluation of thymidylate synthase (TYMS) and RAD23 homolog B (RAD23B) expression in circulating tumor cells (CTCs) provides complementary clinical information. CTCs were prospectively evaluated in 166 blood samples (63 patients) with LARC undergoing NCRT. The primary objective was to verify if the absence of RAD23B/TYMS in CTCs would correlate with pathological complete response (pCR). Secondary objectives were to correlate CTC kinetics before (C1)/after NCRT (C2), in addition to the expression of transforming growth factor-β receptor I (TGF-βRI) with survival rates. CTCs were isolated by ISET and evaluated by immunocytochemistry (protein expression). At C1, RAD23B was detected in 54.1% of patients with no pCR and its absence in 91.7% of patients with pCR (p = 0.014); TYMS^- was observed in 90% of patients with pCR and TYMS⁺ in 51.7% without pCR (p = 0.057). Patients with CTC2 > CTC1 had worse disease-free survival (DFS) (p = 0.00025) and overall survival (OS) (p = 0.0036) compared with those with CTC2 ≤ CTC1. TGF-βRI expression in any time correlated with worse DFS (p = 0.059). To conclude, RAD23B/TYMS and CTC kinetics may facilitate the personalized treatment of LARC.

Can normalized carcinoembryonic antigen following neoadjuvant chemoradiation predict tumour recurrence after curative resection for locally advanced rectal cancer?

AIM

The aim of this work was to evaluate whether normalized carcinoembryonic antigen (CEA) following neoadjuvant chemoradiation predicts the prognosis following curative resection in locally advanced rectal cancer.

METHOD

Patients who underwent neoadjuvant chemoradiation and curative resection for locally advanced rectal cancer between 2010 and 2015 were divided into three groups: Group A (n = 119, normal-to-normal): normal CEA before and after neoadjuvant chemoradiation; Group B (n = 37, high-to-normal): elevated CEA before and normal CEA after neoadjuvant chemoradiation; Group C (n = 36, high-to-high): elevated CEA before and after neoadjuvant chemoradiation. Overall and disease-free survival were compared. Univariate and multivariate analyses identified potential predictors for recurrence.

RESULTS

One hundred and ninety two patients [median age 59 years (range 31-87), 65.1% male] were identified: 54.7% had low rectal cancer: 12.5% were clinical stage T4 and 70.3% were clinically node positive; 21.9% achieved complete pathological response; 24.5% had abdominoperineal resection (APR); and 70.3% underwent adjuvant chemotherapy following curative resection. Significantly more patients in Group C underwent APR (p = 0.0209), had advanced pathological T stage (P = 0.0065) and a higher prevalence of perineural invasion (p = 0.0042). Overall and disease-free survival were significantly higher for Group A than for Group C [hazard ratio (HR) = 4.32, 95% CI = 1.66-11.21, p = 0.0026 and HR=2.68, 95% CI = 1.33-5.40, p = 0.0057, respectively]. No significant difference was noted between Groups A and B for overall (p = 0.0591) or disease-free (p = 0.2834) survival. Another risk factor associated with recurrence and death was clinical T4 stage; nodal positivity was a risk factor only for recurrence.

CONCLUSION

Elevated CEA after neoadjuvant chemoradiation and clinical stage T4 disease were unfavourable predictors for overall and disease-free survival. Normalized CEA during neoadjuvant chemoradiation may serve as a prognosticator, although pretreatment CEA may significantly affect survival.

The Outcome of Induction Chemotherapy, Followed by Neoadjuvant Chemoradiotherapy and Surgery, in Locally Advanced Rectal Cancer

Background & Objective

Currently, neoadjuvant chemoradiotherapy, followed by surgery, is the standard treatment for locally advanced rectal cancer. The use of induction chemotherapy for this tumor is controversial. In this study, the benefits and side effects of induction chemotherapy in locally advanced rectal cancer are evaluated.

Methods

Twenty-nine patients with locally advanced rectal cancer in 2018-2019 were enrolled in this study. Initially, they underwent induction chemotherapy (oxaliplatin 130 mg/m² every 3 weeks and capecitabine 1000 mg/m² twice a day for 14 days every 3 weeks for 2 courses). Then, neoadjuvant chemoradiotherapy (radiotherapy 50.4 Gy/28 for 5 days a week concomitant with weekly oxaliplatin 50 mg/m², as well as capecitabine 825 mg/m²/bid on the days of radiotherapy) was administered. After 4 weeks, computed tomography (CT) scan of thorax, pelvis, and abdomen with and without contrast was performed. Total mesorectal surgery was performed 6-8 weeks after the end of radiotherapy. Four courses of adjuvant chemotherapy were applied. Pathologic complete response (pCR), margin, sphincter preservation, and adverse effects were assessed.

Results

In this study, pCR was present in 6 (20.7%) patients. R0 resection was done in 96.05%. Sphincter was preserved in 44.4% of lower rectal tumors. Two patients (6.9%) did not complete adjuvant treatment. Grade 3 adverse effects were documented in 13.7% of cases during induction chemotherapy and 17.2% of cases during neoadjuvant chemoradiation. Mortality was not reported.

Conclusion

Induction chemotherapy, followed by neoadjuvant chemoradiotherapy and surgery, would be an effective and safe modality in locally advanced rectal cancer.

Evolution and Current Status of the Multidisciplinary Management of Locally Advanced Rectal Cancer

The management of locally advanced rectal cancer has grown in both complexity and quality since the first proctectomy. What once was a malignancy with a fairly consistent treatment algorithm for decades, a recent paradigm shift in the care of these patients has led to a more personalized, multidisciplinary approach with variations in timing, sequence, duration, and potential exclusion of multimodality therapies. This review summarizes the most important evidence behind these developing overarching concepts to provide a context for this paradigm shift.

Outcomes of young patients diagnosed with locally advanced rectal cancer

Background

The incidence of rectal cancer is higher in the older population. In developed nations, there has been a rise in incidence in young onset colorectal cancer (CRC). We examined the outcomes of locally advanced rectal cancer (LARC) in younger patients (yRC) compared with older patients, using a retrospective audit.

Methods

All cases of LARC referred to two tertiary referral cancer centres in Western Sydney were examined. Patient demographics, presenting symptoms, treatment, relapse free survival (RFS), overall survival (OS) and progression free survival (PFS) were obtained. Under 50 years old was used as the cut-off age for defining yRC.

Results

All 145 consecutive patients were treated for LARC, including 28 in the yRC and 117 in the older patient group. Median follow-up was 54 months. yRC were more likely to complete neoadjuvant therapy (100% vs. 86%; P=0.032) and to undergo more extensive surgical procedures (24% vs. 2%, P<0.0001). yRC were more likely to have microsatellite high (MSI) tumours (30% vs. 4.7%; P=0.003). yRC demonstrated significantly poorer RFS compared with the standard group (HR 2.79; median RFS 4.67 vs. 16.02 months; P=0.023). In the relapsed setting, yRC had poorer PFS compared with the standard group (median PFS 2.66 vs. 9.70, P=0.006, HR 3.04). A difference in OS was also seen between the two groups, with yRC demonstrating poorer OS (median OS 40.46 vs. 58.26 months, HR 3.48, P=0.036).

Conclusions

Patients under 50 years with LARC are more likely to have MSI tumours with a more aggressive disease course and poorer RFS, PFS and OS. Initiatives to improve early detection of these patients may improve outcomes. Further research is necessary to understand this disease and optimise its treatment.

Oncological outcomes of lateral lymph node dissection (LLND) for locally advanced rectal cancer: is LLND alone sufficient?

BACKGROUND

Lateral lymph node dissection (LLND) has been considered as the standard treatment strategy for locally advanced lower rectal cancer in Japan. Controversy remains around whether all patients require LLND. This study aims to examine the long-term outcomes of patients in which LLND was performed and clarify the value of LLND.

METHOD

Consecutive 458 patients with lower rectal cancer who underwent total mesorectal excision (TME) plus LLND from 1992 to 2012 were included. The long-term outcomes and risk factors for recurrent in patients performed TME + LLND were examined. We assessed the impact of LLND on survival using an estimated therapeutic index.

RESULTS

The incidence of LLNM was 15.5%. The 5-year RFS and OS rates of patients with LLNM were 40.9% and 47.7%, while patients without LLNM had a good prognosis. The 5-year local recurrence (LR) rate was 9.2%, and independent risk factors for LR were T4 and LLNM. The LR rate of patients with LLNM was high (22.8%). The LLNM rate of the groups with 0, 1, 2, 3, or 4 risk factors (male, tumor location < 4 cm from anal verge, T4, and MLNM) was 3.8%, 9.2%, 18.1%, and 50.0%. The 5-year OS of the groups was 96.2%, 86.1%, 69.7%, and 48.5%.

CONCLUSION

Although patients with locally advanced lower rectal cancer who received LLND had a good prognosis, LLND alone was insufficient to control local recurrence in patients with metastatic lateral nodes.

Tyrosine kinase inhibitors and their unique therapeutic potentialities to combat cancer

Cancer is one of the leading causes of death with a mortality rate of 12%. Although significant progress has been achieved in cancer research, the effective treatment of cancer remains the greatest global challenge in medicine. Dysregulation of tyrosine kinases (TK) is one of the characteristics of several types of cancers. Thus, drugs that target and inhibit these enzymes, known as TK inhibitors (TKIs), are considered vital chemotherapeutics to combat various types of cancer. The oral bioavailability of available TKIs and their targeted therapy are their potential benefits. Based on these characteristics, most TKIs are included in first/second-line therapy for the treatment of different cancers. This review aims to shed light on orally-active TKIs (natural and synthetic molecules) and their promising implication in the therapy of numerous types of tumors along with their mechanisms of action. Further, recent progress in the development of synthetic and isolation of natural TKIs is reviewed. A significant growth in research regarding the development of new-generation TKIs is made with time (23 FDA-approved TKIs from 2018) due to their better therapeutic response. Oral bioavailability should be considered as an important parameter while developing of new-generation TKIs; however, drug delivery systems can also be used to address issue of poor bioavailability to a certain extent. Moreover, clinical trials should be designed in consideration of the development of resistance and tumor heterogeneity.

Neoadjuvant chemotherapy without radiotherapy for patients with locally advanced rectal cancer. Oncologic outcomes

BACKGROUND

the standard treatment for locally advanced rectal cancer is neoadjuvant chemo-radiotherapy, surgery and adjuvant chemotherapy. Only 50% of patients receive the adjuvant treatment due to the surgical complications and toxicity of radiotherapy. Recently, neoadjuvant chemotherapy has been investigated in the locally advanced rectal cancer setting, with the aim of guaranteeing an uninterrupted systemic treatment. The objective of the present study was to assess the safety and efficacy of neoadjuvant chemotherapy in locally advanced rectal cancer.

METHODS AND PATIENTS

patients treated with neoadjuvant chemotherapy and surgery were identified from a prospective database of patients with rectal cancer (cII-III). The primary outcomes were the assessment of the number of R0 resections, the degree of pathologic response, patterns of recurrence and overall and disease-free survival. Treatment schedule: patients received 6-8 cycles of oxaliplatin and fluoropyrimides based chemotherapy.

RESULTS

twenty-seven patients who received neoadjuvant chemotherapy were identified. Twenty-six anterior resections and one Hartmann intervention were performed. An R0 resection was performed in 27 (100%) patients and no involvement of the circumferential margin was observed. Complete pathologic response (ypT0N0) was confirmed in four (14.8%) patients. The median follow-up was 35 months (range: 10-81) and four distant recurrences were recorded. Overall and disease-free survival at five years was 85% and 84.7%, respectively. Twenty-seven (100%) patients received all the cycles of chemotherapy, with a mean of six cycles (range 5-8) per patient.

CONCLUSIONS

neoadjuvant chemotherapy is a promising alternative in the locally advanced rectal cancer setting and further phase III clinical trials are clearly warranted.

Omission of Adjuvant Chemotherapy in Rectal Cancer Patients with Pathologic Complete Response: a National Analysis

BACKGROUND

An increasing number of patients achieve a pathologic complete response (pCR) after neoadjuvant chemoradiation for locally advanced rectal cancer. Consensus guidelines continue to recommend oncologic resection followed by adjuvant chemotherapy in these patients. We hypothesize that there is significant variability in compliance with this recommendation.

METHODS

The National Cancer Database was queried from 2006 to 2015 for patients with locally advanced rectal cancer who underwent neoadjuvant chemoradiation followed by oncologic resection with a pCR (ypT0N0). Hierarchical logistic regression models were used to generate risk and reliability-adjusted rates of adjuvant chemotherapy utilization in patients with pCR at each hospital.

RESULTS

In total, 2421 pCR patients were identified. Five-year overall survival was improved in pCR patients who received adjuvant chemotherapy compared with those who did not (92 vs. 85%, p < 0.01). Multivariate analysis indicated that improvement in overall survival remained associated with adjuvant chemotherapy (HR 0.60, 95% CI 0.44-0.82, p < 0.01). The mean adjuvant chemotherapy utilization rate among hospitals was 32%. There was an upward trend in use over the past decade, but two-thirds still do not receive the recommended therapy. High chemotherapy utilizer hospitals were more likely to be academic centers (54.9 vs. 45.9%, p < 0.01) when compared with low chemotherapy utilizers.

CONCLUSION

Adjuvant chemotherapy is associated with improved survival in rectal cancer patients with pCR following neoadjuvant chemoradiation and oncologic resection. However, utilization among centers in the USA was only 32% with significant variability across centers. National efforts are needed to standardize treatment patterns according to national guidelines.

Pretreatment Albumin-to-Fibrinogen Ratio Independently Predicts Chemotherapy Response and Prognosis in Patients with Locally Advanced Rectal Cancer Undergoing Total Mesorectal Excision After Neoadjuvant Chemoradiotherapy

Background

Neoadjuvant chemoradiotherapy (nCRT) followed by surgery of total mesorectal excision (TME) is currently accepted as the standard treatment for locally advanced rectal cancer (LARC). This study aimed to investigate the potential prognostic factors, including the albumin-to-fibrinogen ratio (AFR) for LARC patients.

Methods

We retrospectively recruited LARC patients (cT3-4 and/or cN1-2) who underwent nCRT followed by TME between January 2011 and January 2015. The cut-off value of pretreatment AFR for overall survival (OS) was determined by the receiver operating characteristic (ROC) curve. The potential predictive factors for prognosis in the LARC patients were assessed by the univariate and multivariate Cox’s proportional hazard regression and Kaplan–Meier curve analyses.

Results

AFR was a significant predictor for OS with a cut-off value of 8.65 and an AUC of 0.882 (P<0.001). The pretreatment AFR level was the only independent risk factor for pathologic response to nCRT (HR: 2.44, 95% CI: 1.43–4.17, P=0.003), 5-year OS (HR: 3.31, 95% CI: 1.51–6.77, P=0.005) and disease-free survival (DFS) (HR: 2.73, 95% CI: 1.34–5.47, P=0.007) in LARC patients. A low pretreatment AFR level was significantly associated with a poor 5-year OS and DFS by the Log rank test (P=0.003 and 0.006, respectively).

Conclusion

Pretreatment AFR level was an independent prognostic factor in LARC patients undergoing TME after nCRT.

Neoadjuvant chemotherapy and radiation therapy in veterinary cancer treatment: a review

Multi-modality treatment strategies are more becoming commonplace in veterinary oncology practice yet the evidence base is far inferior to what has been generated in people. Surgery is unquestionably the cornerstone of most solid tumour treatment plans but certain scenarios dictate combining surgery with systemic chemotherapy and radiation therapy as an adjunct. By using these in the neoadjuvant setting, one can leverage certain effects of the treatment to improve local disease control, improve overall survival, gain insight into drug efficacy, reduce surgical morbidity and reduce long-term complications. An unintended consequence of combining therapies is an increased flow of information between members of the care team upfront that in almost all cases leads to improved patient outcomes albeit a difficult metric to quantify. This review sets out to explore some of the principles of neoadjuvant therapies and discuss potential opportunities to expand the evidence base in veterinary medicine.

Prognostic Value of Interval Between the Initiation of Neoadjuvant Treatment to Surgery for Patients With Locally Advanced Rectal Cancer Following Neoadjuvant Chemotherapy, Radiotherapy and Definitive Surgery

Background: The addition of intensive preoperative chemotherapy and using of a longer waiting period between neoadjuvant radiotherapy and total mesorectal excision (TME) surgery lengthen the time interval from the initiation of neoadjuvant treatment to definitive surgery in patients with locally advanced rectal cancer (LARC). Here, we evaluated the prognostic value of different time intervals between the initiation of neoadjuvant treatment to TME surgery for LARC. Methods: A total of 2,267 patients with LARC, who received neoadjuvant radiochemotherapy and TME surgery, between January 2010 through December 2018 were recruited. The entire cohort was divided into 4 subgroups based on total-time-to surgery, defined as the time interval between initiation of neoadjuvant treatment and TME surgery (TTS): <13 weeks (TTS-1), 13 to <15 weeks (TTS-2), 15 to <17 weeks (TTS-3), ≥17 weeks (TTS-4). Overall survival (OS), disease-free survival (DFS), distant metastasis-free survival (DMFS), and local recurrence-free survival (LRFS) rates in different TTS subgroup patients were compared, and hazard ratios (HR) for different demographic and clinicopathological variables, including TTS, were calculated to determine their prognostic significance. Results: The median follow-up time was 42.0 (range, 5-162) months. The 3-year OS, DFS, DMFS, and LRFS rates were 87.0, 79.4, 80.9, and 93.8%, respectively. The varied OS, DFS, and DFMS rates were detected among these different TTS subgroups (P = 0.010, P < 0.001, and P < 0.001, respectively). Particularly, the lower survival outcome was mainly observed at patients in the shortest TTS group (TTS-1). Cox regression analysis confirmed that the only significant positive independent prognostic factor for 3-year DFS was a longer TTS (TTS 2-4 vs. TTS-1; HR 0.884, 95% CI 0.778-0.921, P < 0.001), while the significant negative independent prognosticfactors were moderate to poor tumor differentiation (vs. well-differentiated; HR 1.191, 95% CI 1.004-1.414, P = 0.045) and clinical N1-2 stage (vs. N0 stage; HR 1.190, 95% CI 1.052-1.347, P = 0.006). Conclusion: For patients with LARC, an interval between the initiation of neoadjuvant treatment and TME surgery of longer than 13 weeks is associated with favorable disease-free survival.

Post-Operative Morbidity and Mortality Following Total Neoadjuvant Therapy Versus Conventional Neoadjuvant Chemoradiotherapy in Locally Advanced Rectal Cancer

BACKGROUND

Standard of care for locally advanced rectal cancer (LARC) (stage II/III) includes preoperative chemoradiation (CRT) followed by resection and adjuvant chemotherapy. Total neoadjuvant therapy (TNT) is a new treatment paradigm that delivers systemic therapy prior to CRT aimed at improving outcomes for high-risk patients. Here we analyzed the national cancer database (NCDB) comparing short-term post-operative outcomes between patients receiving TNT and CRT.

METHODS

The NCDB was queried to identify patients with LARC between the 2004 and 2014 treated with TNT or CRT. Primary outcomes included post-operative 30-day mortality and readmissions between TNT and CRT which were analyzed via logistic regression. Secondary outcomes included post-operative length of stay (LOS) and OS which were compared with two-tailed t-test and Kaplan-Meier with log rank testing, respectively.

RESULTS

A total of 9066 patients met inclusion criteria with a median age at diagnosis that was 57 years (IQR, 19-65); 62.3% were male and 87.8% white. Neoadjuvant therapy consisted of either standard CRT (97.2%) or TNT (2.8%). Patients treated at academic programs and those with N1 [p < 0.001, OR 2.34, 95%CI 1.71-3.19] or N2 [p < 0.001, OR 3.29, 95%CI 2.19-4.94] disease were associated with increased utilization of TNT. TNT was not significantly associated with either 30-day mortality (p = 1.0) or readmissions (p = 0.82). Further, there was no significant difference identified between CRT and TNT for hospital LOS or OS (p = 0.18).

CONCLUSION

This large-scale analysis of patients with LARC demonstrates increased utilization of TNT in patients harboring node-positive disease. Further, TNT does not appear to increase 30-day post-operative mortality, readmissions, or hospital LOS.

Advances in the treatment of locally advanced rectal cancer

Locally advanced rectal cancer requires multidisciplinary care. In the United States, most patients are treated with neoadjuvant chemoradiation delivered over 25‐28 days, total mesorectal excision, and 4 months of adjuvant chemotherapy. While effective, this trimodal approach is arduous. Alternative approaches have emerged to streamline treatment without sacrificing oncologic outcomes. These approaches include preoperative chemotherapy with selective use of radiation, short‐course radiotherapy delivered over 5 days, and total neoadjuvant therapy with attempted nonoperative organ‐preserving management (watch and wait). Ongoing trials are assessing the efficacies of these approaches in combination with various risk stratification strategies.

Prognostic Significance of Neoadjuvant Rectal Scores in Preoperative Short-Course Radiotherapy and Long-Course Concurrent Chemoradiotherapy for Patients with Locally Advanced Rectal Cancer

BACKGROUND

This study aimed to investigate the prognostic factors and the utility of the neoadjuvant rectal (NAR) score for patients who have locally advanced rectal cancer (LARC) treated with preoperative short-course radiotherapy (SRT) or long-course concurrent chemoradiotherapy (CRT).

METHODS

Of 314 consecutive stage 2 or 3 rectal cancer patients enrolled from January 2006 to December 2017, 205 underwent preoperative SRT (2500 cGy/5 fractions), and 109 underwent preoperative CRT (4200-5080 cGy/21-28 fractions) after total mesorectal excision (TME). The study calculated NAR scores using the following equation: [5 pN - 3(cT - pT) + 12]²/9.61.

RESULTS

The multivariate analysis showed that age above 65 years, pT4, pN2, NAR scores higher than 16, and distance from anal verges (< 8 cm) were significant prognostic factors for overall survival (OS), whereas, pN2, NAR scores lower than 16, and distance from anal verges (< 8 cm) were significant prognostic factors for disease-free survival (DFS) and distant metastasis (DM). The patients with an NAR score higher than 16, had a 5-year OS rate of 67.6%, a DFS rate of 56.9%, a locoregional recurrence (LRR) rate of 7.7%, and a DM rate of 35% compared with corresponding rates of 87.6%, 76.7%, 5.4%, and 7.2% for the patients with an NAR score of 16 or lower (p < 0.001 for OS, < 0.001 for DFS, 0.25 for LRR, and < 0.001 for DM).

CONCLUSIONS

For patients who undergo SRT or CRT for LARC, a higher NAR score is associated with worse OS and DFS and higher DM rates at 5 years. The NAR score could be used as a short-term surrogate end point after neoadjuvant therapy for LARC.

A Comprehensive Review of Randomized Clinical Trials Shaping the Landscape of Rectal Cancer Therapy

Colorectal carcinoma is the second leading cause of cancer-related deaths in the United States, with rectal cancer accounting for approximately one third of newly diagnosed cases. Surgery remains the cornerstone of curative therapy, with total mesorectal excision being the standard of care. Although minimally invasive procedures might be appropriate for a subset of patients with early-stage, superficial tumors, the standard of care for medically operable patients with nonmetastatic rectal cancer includes a comprehensive multimodality approach of neoadjuvant chemoradiotherapy, surgery with total mesorectal excision, and systemic chemotherapy. However, the morbidity and mortality related to both local and distant organ relapse have remained challenging. In the present review, we have discussed the trial-level evidence that has shaped the current clinical practice patterns in the treatment of curable, nonmetastatic rectal cancer. In addition, we have discussed the anticipated results of ongoing clinical trials and outlined pragmatic opportunities for future investigation to optimize the current status quo and, hopefully, provide prospective validation of novel approaches in the treatment of rectal cancer.

Impact of Prolonged Neoadjuvant Treatment-surgery Interval on Histopathologic and Operative Outcomes in Patients Undergoing Total Mesorectal Excision for Locally Advanced Rectal Cancer

BACKGROUND

This study primarily aimed to assess the impact of prolonged neoadjuvant treatment-surgery interval (PNSI) on histopathologic and postoperative outcomes. Impacts of the mode of neoadjuvant treatment (NT) and surgery on the outcomes were also evaluated in the same patient population.

PATIENTS AND METHODS

Between February 2011 and December 2017, patients who underwent NT and total mesorectal excision for locally advanced rectal cancer were included. PNSI was defined as >4 and >8 weeks after short-course and long-course NT modalities, respectively.

RESULTS

A total of 44 (27%) patients received short-course NT (standard interval: n=28; PNSI: n=16) and 122 (73%) patients received long-course NT (standard interval: n=39; PNSI: n=83). Postoperative morbidity was similar between the standard interval and PNSI in patients undergoing short-course [n=3 (11%) vs. n=3 (19%), P=0.455] and long-course [n=6 (15%) vs. n=16 (19%), P=0.602] NT. PNSI was associated with increased complete pathologic response in patients receiving short-course NT [0 vs. n=5 (31%), P=0.002]. Compared with short-course NT, long-course NT was superior in terms of tumor response based on the Mandard [Mandard 1 to 2: n=6 (21%) vs. 6 (38%), P=0.012] and the College of American Pathologists (CAP) [CAP 0 to 1: n=13 (46%) vs. n=8 (50%), P=0.009] scores. Postoperative morbidity was similar after open, laparoscopic, and robotic total mesorectal excision [n=1 (14.2%) vs. n=21 (21%) vs. n=6 (12.5%), P=0.455] irrespective of the interval time to surgery and the type of NT.

CONCLUSIONS

PNSI can be considered in patients undergoing short-course NT due to its potential oncological benefits. The mode of surgery performed at tertiary centers has no impact on postoperative morbidity after both NT modalities.

Pathological Predictors of Response to Neoadjuvant Treatment in Rectal Carcinoma

PURPOSE

Neoadjuvant chemoradiotherapy has now become a standard treatment for rectal cancer. Recently, attempts have been made to predict the response rate to this treatment to decide whether or not it must be performed. However, tissue factors for predicting the response rate is not cohesively reviewed.

METHODS

Eighty-three patients with rectal cancer, all under neoadjuvant chemoradiotherapy and subsequent surgery, were examined for tissue factors in the biopsy sample. The tissue factors examined include tumor differentiation grade, lymphovascular invasion, perineural invasion, pathological stage, and lymphocytic infiltration. Lymphocytic infiltration was investigated by immunohistochemistry for CD8 T lymphocyte in biopsy samples.

RESULTS

In this study, tissue factors were found to play a decisive role in predicting response to neoadjuvant treatment. The most important factor was the pathological stage, which has the highest correlation with response to treatment. There is a significant relationship between CD8 lymphocyte infiltration and response to treatment (P value = 0.018). Primary perineural invasion and lymphovascular invasion also have a significant meaningful relationship with response to treatment (P value = 0.021 and P value = 0.036).

CONCLUSION

In this study, it was determined that the investigated factors have a significant relationship with response to treatment and could be used to predict the response to treatment, and if a low possibility of positive response exists, prevention of the complications of neoadjuvant chemoradiotherapy for the patients could occur.

Adding Boost to Standard Neoadjuvant Radiation for Rectal Cancer Improves Likelihood of Complete Response

BACKGROUND

Pathologic tumor response is a prognostic factor for survival in patients with rectal cancer. Standard neoadjuvant radiation (nRT) dosing for locally advanced rectal cancer ranges from 4500 to 5400 centigray (cGy), but it is unknown if tumor regression differs as a consequence adding a boost to the tumor bed.

METHODS

The National Cancer Database (NCDB) 2006-2016 was used to identify patients 18 years of age and older with clinical stage II and III rectal cancer who received pelvic nRT dosed between 4500 and 5400 cGy. Standard nRT dose (no boost, NB) and dose with boost (DWB) were defined respectively as 4500 and 5040-5400 cGy. Complete pathologic response (pCR) was defined as postoperative pathologic stage of zero. A multivariate logistic regression was performed to evaluate the association between radiation dosing and pCR.

RESULTS

The study cohort was 28,841 patients; the majority received DWB 22,701 (78.7%), while 6140 (21.3%) received NB. pCR was achieved in 3135 (14.4%) patients. On multivariate analysis, patients who received NB were significantly less likely to have complete tumor response (OR 1.41, 95% CI 1.2-1.66, p < 0.001). Other factors significantly associated with pCR included insurance, facility type, tumor characteristics, clinical stage, and time between radiation and surgery.

CONCLUSIONS

This is the first investigation demonstrating that standard dose neoadjuvant radiation for rectal cancer was associated with a lower likelihood of pCR compared with standard dose with boost. Past studies demonstrate that rectal cancer patient survival is strongly correlated with pCR. Prospective trials should focus on examining neoadjuvant radiation dosing to evaluate if DWB improves outcomes.