Capecitabine and oxaliplatin in the preoperative multimodality treatment of rectal cancer: surgical end points from National Surgical Adjuvant Breast and Bowel Project trial R-04

The multidisciplinary management of locally advanced rectal cancer

INTRODUCTION

The classic paradigm for the management of locally advanced rectal cancer (LARC) consists of (chemo)radiotherapy (C)RT), total mesorectal excision, and adjuvant chemotherapy (CHT). At present, due to the high rate of distant metastasis (up to 30%), the total neoadjuvant therapy (TNT) with the administration of systemic CHT in the neoadjuvant setting has gained acceptance as standard of care.Our aim is to critically review the current literature on LARC management and summarize the different approaches recently proposed to improve clinical outcomes. It represents a starting step to develop an effective strategy that ultimately could harmonize the standard of care in daily clinical practice.

AREAS COVERED

Studies reporting the impact of TNT approaches were deemed eligible. De-escalation strategies, including non-operative management (NOM) after TNT, as well as RT omission or systemic therapy alone, were also investigated.

EXPERT OPINION

The year 2020 has seen promising new data from randomized phase III trials in the field of LARC management. Nowadays, TNT strategy has been accepted as the primary treatment for LARC. The role of de-escalation strategies is still unknown. The goal is to achieve better survival outcomes with improving quality of life. Only selected patients are likely to benefit from NOM or immunotherapy alone.

Rectal Cancer Survival for Residual Carcinoma In Situ Versus Pathologic Complete Response After Neoadjuvant Therapy

BACKGROUND

Pathologic complete response after neoadjuvant chemoradiotherapy for rectal cancer is associated with improved survival. It is unclear whether residual carcinoma in situ portends a similar outcome.

OBJECTIVE

To compare the survival of patients with locally advanced rectal cancer who received neoadjuvant therapy and achieved pathologic carcinoma in situ versus pathologic complete response.

DESIGN

Retrospective cohort study.

SETTING

National public database.

PATIENTS

A total of 4594 patients in the National Cancer Database from 2006 to 2016 with locally advanced rectal cancer who received neoadjuvant therapy, underwent surgery, and had node-negative ypTis or ypT0 on final pathology were included. Of these, 4321 patients (94.1%) had ypT0 and 273 (5.9%) had ypTis on final pathology.

MAIN OUTCOME MEASURE

Overall survival.

RESULTS

The median age was 60 years, and 1822 patients (39.7%) were women. On initial staging, 54.5% (n = 2503) had stage II disease and 45.5% (n = 2091) had stage III disease. The ypTis group had decreased overall survival compared to the ypT0 group (HR 1.42; 95% CI, 1.04-1.95; p  = 0.028). Other factors associated with decreased overall survival were older age at diagnosis, increasing Charlson-Deyo score, and poorly differentiated tumor grade. Variables associated with improved survival were female sex, private insurance, and receipt of both neoadjuvant and adjuvant chemotherapy. For the total cohort, there was no difference in survival between clinical stage II and stage III.

LIMITATIONS

Standard therapy versus total neoadjuvant therapy could not be abstracted. Overall survival was defined as the time from surgery to death from any cause or last contact, allowing for some erroneously misclassified deaths.

CONCLUSIONS

ypTis is associated with worse overall survival than ypT0 for patients with locally advanced rectal cancer who receive neoadjuvant chemoradiotherapy followed by surgery. For this cohort, clinical stage was not a significant predictor of survival. Prospective trials comparing survival for these pathologic outcomes are needed. See Video Abstract .

SUPERVIVENCIA DEL CNCER DE RECTO PARA EL CARCINOMA RESIDUAL IN SITU VS RESPUESTA PATOLGICA COMPLETA DESPUS DE LA TERAPIA NEOADYUVANTE

ANTECEDENTESLa respuesta patológica completa después de la quimiorradioterapia neoadyuvante para el cáncer de recto se asocia con una mayor supervivencia. No está claro si el carcinoma residual in situ presagia un resultado similar.OBJETIVOComparar la supervivencia de pacientes con cáncer de recto localmente avanzado que recibieron terapia neoadyuvante y lograron un carcinoma patológico in situ versus una respuesta patológica completa.DISEÑOEstudio de cohorte retrospectivo.ESCENARIOBase de datos pública nacional.PACIENTESSe incluyeron 4,594 pacientes de la Base de Datos Nacional de Cáncer de 2006 a 2016 con cáncer de recto localmente avanzado que recibieron terapia neoadyuvante, fueron sometidos a cirugía y tuvieron ganglios negativos, ypTis o ypT0 en el reporte patológico final. 4.321 (94,1%) tuvieron ypT0 y 273 (5,9%) tuvieron ypTis en el reporte final.PRINCIPALES MEDIDAS DE RESULTADOSupervivencia general.RESULTADOSLa mediana de edad fue de 60 años. 1.822 pacientes (39,7%) fueron mujeres. El 54,5% (n = 2.503) tuvo la enfermedad en estadio II y el 45,5% (n = 2.091) tuvo la enfermedad en estadio III según la estadificación inicial. El grupo ypTis tuvo una supervivencia general reducida en comparación con el grupo ypT0 (HR 1,42, IC 95 % 1,04-1,95, p = 0,028). Otros factores asociados con una menor supervivencia general fueron una edad más avanzada al momento del diagnóstico, un aumento de la puntuación de Charlson-Deyo y un grado tumoral poco diferenciado. Las variables asociadas con una mejor supervivencia fueron el sexo femenino, el seguro privado y la recepción de quimioterapia neoadyuvante y adyuvante. Para la cohorte total, no hubo diferencias en la supervivencia entre el estadio clínico 2 y el estadio 3.LIMITACIONESNo se pudo resumir el tratamiento estándar versus el tratamiento neoadyuvante total. La supervivencia general se definió como el tiempo transcurrido desde la cirugía hasta la muerte por cualquier causa o último contacto, lo que permite algunas muertes erróneamente clasificadas.CONCLUSIONESypTis se asocia con una peor supervivencia general que ypT0 en pacientes con cáncer de recto localmente avanzado que reciben quimiorradioterapia neoadyuvante seguida de cirugía. Para esta cohorte, el estadio clínico no fue un predictor significativo de supervivencia. Se necesitan ensayos prospectivos que comparen la supervivencia de estos resultados patológicos. ( Traducción-Dr Osvaldo Gauto ).

Treatment of Locally Advanced Rectal Cancer in the Era of Total Neoadjuvant Therapy: A Systematic Review and Network Meta-Analysis

Importance

Treatment of locally advanced rectal cancer (LARC) involves neoadjuvant chemoradiotherapy plus total mesorectal excision and adjuvant chemotherapy. However, total neoadjuvant therapy (TNT) protocols (ie, preoperative chemotherapy in addition to radiotherapy) may allow better adherence and early treatment of distant micrometastases and may increase pathological complete response (pCR) rates.

Objective

To assess the efficacy and tolerability of TNT protocols for LARC.

Data Sources

MEDLINE, Embase, Cochrane Central Register of Controlled Trials (CENTRAL), and Web of Science Core Collection electronic databases and ClinicalTrials.gov for unpublished studies were searched from inception to March 2, 2024.

Study Selection

Randomized clinical trials including adults with LARC who underwent rectal resection as a final treatment were included. Studies including nonoperative treatment (watch-and-wait strategy), treatments other than rectal resection, immunotherapy, or antiangiogenic agents were excluded. Among the initially identified studies, 2.9% met the selection criteria.

Data Extraction and Synthesis

Two authors independently screened the records and extracted data. Preferred Reporting Items for Systematic Reviews and Meta-analyses (PRISMA)-compliant pairwise and network meta-analyses with a random-effects model were performed in a frequentist framework, and the certainty of evidence was assessed according to the confidence in network meta-analysis approach.

Main Outcomes and Measures

The primary outcome was pCR, defined as the absence of residual tumor at pathological assessment after surgery. Secondary outcomes included tolerability, toxic effects, perioperative outcomes, and long-term survival.

Results

Of 925 records identified, 27 randomized clinical trials, including 13 413 adults aged 18 years or older (median age, 60.0 years [range, 42.0-63.5 years]; 67.2% male) contributed to the primary network meta-analysis. With regard to pCR, long-course chemoradiotherapy (L-CRT) plus consolidation chemotherapy (relative risk [RR], 1.96; 95% CI, 1.25-3.06), short-course radiotherapy (S-RT) plus consolidation chemotherapy (RR, 1.76; 95% CI, 1.34-2.30), and induction chemotherapy plus L-CRT (RR, 1.57; 95% CI, 1.09-2.25) outperformed standard L-CRT with single-agent fluoropyrimidine-based chemotherapy. Considering 3-year disease-free survival, S-RT plus consolidation chemotherapy (RR, 1.08; 95% CI, 1.01-1.14) and induction chemotherapy plus L-CRT (RR, 1.12; 95% CI, 1.01-1.24) outperformed L-CRT, in spite of an increased 5-year locoregional recurrence rate of S-RT plus consolidation chemotherapy (RR, 1.65; 95% CI, 1.03-2.63).

Conclusions and Relevance

In this systematic review and network meta-analysis, 3 TNT protocols were identified to outperform the current standard of care in terms of pCR rates, with good tolerability and optimal postoperative outcomes, suggesting they should be recognized as first-line treatments.

Penile-scrotal erythrodysesthesia among rectal cancer patients receiving fluoropyrimidine-based chemoradiation: a case report series

BACKGROUND

Palmar-plantar erythrodysesthesia (PPE) is a slowly developing cutaneous reaction commonly experienced by patients treated with fluoropyrimidines. While erythrodysesthesia normally presents in a palmar-plantar distribution, it can also present with genital involvement, but this presentation is likely underreported and incorrectly attributed to an acute reaction from radiation therapy. This article aims to define erythrodysesthesia of the penis and scrotum as a rare but significant side effect of capecitabine.

CASE PRESENTATION

We identified five cases of moderate to severe penis and scrotal erythrodysesthesia over a 2-year period at a large tertiary cancer center, representing an estimated incidence of 3.6% among male patients with rectal cancer who were treated with fluoropyrimidine-based chemoradiation within our institution.

CONCLUSIONS

Improved understanding of erythrodysesthesia involving the penis and scrotum can facilitate early identification and treatment of symptoms, and possibly prevent the discontinuation or delay of cancer treatment in patients treated with capecitabine and similar drugs. These clinical advances would improve and prolong patient quality of life during cancer treatment and prevent complications that result in hospitalization.

Prediction of survival after neoadjuvant therapy in locally advanced rectal cancer - a retrospective analysis

Purpose

The aim of this retrospective analysis was to determine if the response to preoperative radio(chemo)therapy is predictive for survival among patients with locally advanced rectal cancer and may act as a potential surrogate endpoint for disease free survival and overall survival.

Results

Eight hundred seventy-eight patients from five centers were analyzed. There were 304 women and 574 men; the median age was 64.7 years. 77.6% and 22.4% of patients received neoadjuvant radiochemotherapy or short-course radiotherapy, resulting in a pathological complete response in 7.3%. T-downstaging and N-downstaging occurred in 50.5% and 37% of patients after neoadjuvant therapy. In patients with T-downstaging, the 10-year DFS and 10-year OS were 64.8% and 66.8% compared to 37.1% and 45.9% in patients without T-downstaging. N-downstaging resulted in 10-year DFS and 10-year OS in 56.2% and 62.5% compared to 47.3% and 52.3% without N-downstaging. Based on routinely evaluated clinical parameters, an absolute risk prediction calculator was generated for 5-year disease-free survival, and 5-year overall survival.

Conclusion

T-downstaging and N-downstaging after neoadjuvant radiochemotherapy or short-course radiotherapy resulted in better DFS and OS compared to patients without response. Based on clinical parameters, 5-year DFS, and 5-year OS can be predicted using a prediction calculator.

Retrospective Evaluation of the Efficacy of Total Neoadjuvant Therapy and Chemoradiotherapy Neoadjuvant Treatment in Relation to Surgery in Patients with Rectal Cancer

Background and Objective: In the therapeutic strategy of rectal cancer, radiotherapy has consolidated its important position and frequent use in current practice due to its indications as neoadjuvant, adjuvant, definitive, or palliative treatment. In recent years, total neoadjuvant therapy (TNT) has been established as the preferred regimen compared to concurrent neoadjuvant chemoradiotherapy (CRT). In relation to better outcomes, the percentage of patients who achieved pathological complete response (pCR) after neoadjuvant treatment is higher in the case of TNT. This study aimed to analyze the response to TNT compared to neoadjuvant CRT regarding pCR rate and the change in staging after surgical intervention. Materials and Methods: We performed a retrospective study on 323 patients with rectal cancer and finally analyzed the data of 201 patients with neoadjuvant treatment, selected based on the inclusion and exclusion criteria. Patients received CRT neoadjuvant therapy or TNT neoadjuvant therapy with FOLFOX or CAPEOX. Results: Out of 157 patients who underwent TNT treatment, 19.74% had pathological complete response, whereas in the group with CRT (n = 44), those with pCR were 13.64%. After neoadjuvant treatment, the most frequent TNM classifications were ypT2 (40.30%) and ypN0 (79.10%). The statistical analysis of the postoperative disease stage, after neoadjuvant therapy, showed that the most frequent changes were downstaging (71.14%) and complete response (18.41%). Only four patients (1.99%) had an upstaging change. The majority of patients (88.56%) initially presented clinical evidence of nodal involvement whereas only 20.9% of the patients still presented regional disease at the time of surgical intervention. Conclusions: By using TNT, a higher rate of stage reduction is obtained compared to the neoadjuvant CRT treatment. The post-neoadjuvant-treatment imagistic evaluation fails to accurately evaluate the response. A better response to TNT was observed in young patients.

Combinatorial Approaches for Chemotherapies and Targeted Therapies With Radiation: United Efforts to Innovate in Patient Care

Combinatorial therapies consisting of radiation therapy (RT) with systemic therapies, particularly chemotherapy and targeted therapies, have moved the needle to augment disease control across nearly all disease sites for locally advanced disease. Evaluating these important combinations to incorporate more potent therapies with RT will aid our understanding of toxicity and efficacy for patients. This article discusses multiple disease sites and includes a compilation of contributions from expert Red Journal editors from each disease site. Leveraging improved systemic control with novel agents, we must continue efforts to study novel treatment combinations with RT.

Recent advances in rectal cancer treatment - are we on the right track?

Background

Staging and treatment of rectal cancer have evolved over several decades with considerably fewer locoregional recurrences but no marked improved survival since systemic recurrence risks remain virtually unchanged. This development will briefly be summarised followed by a thorough discussion of two recent developments.

Methods

A systematic approach towards the literature is aimed at focusing on organ preservation and the delivery of all non-surgical treatments prior to surgery or total neoadjuvant treatment (TNT).

Results

Organ preservation, that is to defer surgery if the tumour happens to disappear completely after any pre-treatment given to locally advanced tumours to decrease recurrence risks has increased in popularity and is, if not universally, widely accepted. To give neo-adjuvant treatment to intentionally obtain a clinically complete remission to avoid surgery is practised in some environments but is mostly still experimental. TNT, that is to provide both radiotherapy and chemotherapy aimed at killing microscopic disease in the pelvis or elsewhere has been subject to several trials. Collectively, they show that the chance of achieving a complete response, pathologically or clinically, has approximately doubled, increasing the chance for organ preservation, and the risk of distant metastasis has decreased at least in some trials. The best schedule remains to be established.

Conclusions

To obtain substantial progress and also improve survival, the systemic treatments need to be improved even if preoperative delivery is more effective and better tolerated than postoperative. The locoregional treatment may be further optimised through better risk prediction.

Adoption of Total Neoadjuvant Therapy in the Treatment of Locally Advanced Rectal Cancer

Local and metastatic recurrence are primary concerns following the treatment of locally advanced rectal cancer (LARC). Chemoradiation (CRT) can reduce the local recurrence rates and has subsequently moved to the neoadjuvant setting from the adjuvant setting. Pathological complete response (pCR) rates have also been noted to be greater in patients treated with neoadjuvant CRT prior to surgery. The standard approach to treating LARC would often involve CRT followed by surgery and optional adjuvant chemotherapy and remained the treatment paradigm for almost two decades. However, patients were often unable to complete adjuvant chemotherapy due to a decreased tolerance of chemotherapy following surgery, which led to upfront treatment with both CRT and chemotherapy, and total neoadjuvant therapy, or TNT, was created. The efficacy outcomes of local recurrence, disease-free survival, and pCR have improved in patients receiving TNT compared to the standard approach. Additionally, more recent data suggest a possible improvement in overall survival as well. Patients with a complete clinical response following TNT have the opportunity for watch-and-wait surveillance, allowing some patients to undergo organ preservation. Here, we discuss the clinical trials and studies that led to the adoption of TNT as the standard of care for LARC, with the possibility of watch-and-wait surveillance for patients achieving complete responses. We also review the possibility of overtreating some patients with LARC.

Quality of Surgical Outcome Reporting in Randomised Clinical Trials of Multimodal Rectal Cancer Treatment: A Systematic Review

INTRODUCTION

Randomised controlled trials (RCTs) continue to provide the best evidence for treatment options, but the quality of reporting in RCTs and the completeness rate of reporting of surgical outcomes and complication data vary widely. The aim of this study was to measure the quality of reporting of the surgical outcome and complication data in RCTs of rectal cancer treatment and whether this quality has changed over time.

METHODS

Eligible articles with the keywords ("rectal cancer" OR "rectal carcinoma") AND ("radiation" OR "radiotherapy") that were RCTs and published in the English, German, Polish, or Italian language were identified by reviewing all abstracts published from 1982 through 2022. Two authors independently screened and analysed all studies. The quality of the surgical outcome and complication data was assessed based on fourteen criteria, and the quality of RCTs was evaluated based on a modified Jadad scale. The primary outcome was the quality of reporting in RCTs and the completeness rate of reporting of surgical results and complication data.

RESULTS

A total of 340 articles reporting multimodal therapy outcomes for 143,576 rectal cancer patients were analysed. A total of 7 articles (2%) met all 14 reporting criteria, 13 met 13 criteria, 27 met from 11 to 12 criteria, 36 met from 9 to 10 criteria, 76 met from 7 to 8 criteria, and most articles met fewer than 7 criteria (mean 5.5 criteria). Commonly underreported criteria included complication severity (15% of articles), macroscopic integrity of mesorectal excision (17% of articles), length of stay (18% of articles), number of lymph nodes (21% of articles), distance between the tumour and circumferential resection margin (CRM) (26% of articles), surgical radicality according to the site of the primary tumour (R0 vs. R1 + R2) (29% of articles), and CRM status (38% of articles).

CONCLUSION

Inconsistent surgical outcome and complication data reporting in multimodal rectal cancer treatment RCTs is standard. Standardised reporting of clinical and oncological outcomes should be established to facilitate comparing studies and results of related research topics.

Implications of Rectal Cancer Radiotherapy on the Immune Microenvironment: Allies and Foes to Therapy Resistance and Patients' Outcome

Aside from surgical resection, locally advanced rectal cancer is regularly treated with neoadjuvant chemoradiotherapy. Since the concept of cancer treatment has shifted from only focusing on tumor cells as drivers of disease progression towards a broader understanding including the dynamic tumor microenvironment (TME), the impact of radiotherapy on the TME and specifically the tumor immune microenvironment (TIME) is increasingly recognized. Both promoting as well as suppressing effects on anti-tumor immunity have been reported in response to rectal cancer (chemo-)radiotherapy and various targets for combination therapies are under investigation. A literature review was conducted searching the PubMed database for evidence regarding the pleiotropic effects of (chemo-)radiotherapy on the rectal cancer TIME, including alterations in cytokine levels, immune cell populations and activity as well as changes in immune checkpoint proteins. Radiotherapy can induce immune-stimulating and -suppressive alterations, potentially mediating radioresistance. The response is influenced by treatment modalities, including the dosage administered and the highly individual intrinsic pre-treatment immune status. Directly addressing the main immune cells of the TME, this review aims to highlight therapeutical implications since efficient rectal cancer treatment relies on personalized strategies combining conventional therapies with immune-modulating approaches, such as immune checkpoint inhibitors.

Does neoadjuvant rectal score predict treatment outcomes better than the all grading systems used in neoadjuvantly treated rectal cancer?

BACKGROUND

/Objective: To compare the prognostic value of the yield pathologic (yp) stage, used 4 tumor regression grading (TRG) systems, and neoadjuvant rectal score(NARS) in patients with locally advanced rectal cancer (LARC) who received long-term neoadjuvant chemoradiotherapy (nCRT).

METHODS

Between 2005 and 2017, we included 302 patients with LARC who treated with nCRT. Postoperative pathological responses were graded by using Dworak, American Joint Committee on Cancer, Mandart, Memorial Sloan Kettering Cancer Center, grading systems and NARS([5ypN-3(kT-pT)+12]2/9,61) calculations. Their results were compared in terms of treatment outcomes.

RESULTS

The median follow-up time was 51 months (range 5-136). There was a significant relation between cT stage and the response in used grading systems(p < 0,001). Median overall(OS), local recurrence free(LRFS), and distant metastasis free(MFS) survival rates were 50, 48, and 45 months, respectively. 5-year OS, LRFS, and MFS rates were 71%, 92%, and 72%, respectively. According to the NARS and treatment response grating systems, a significant difference was found between the low risk and high risk groups in terms of OS, LRFS, and MFS rates. While it was not seen any difference in terms of OS and MFS, NARS was found to predict LRFS better than other grading systems. In multivariate analysis, high NARS was found to be correlated with worse OS and worse MFS. On the other hand, pCR was the another important factor affecting treatment outcomes.

CONCLUSIONS

While used systems except NARS group patients according to ypT status in surgical tissue, NARS add the value of ypN status in addition to ypT status. It could be suggested to use NARS to predict LRFS.

Retrospective Evaluation of the Impact of Dose Escalation Using Pre-operative Simultaneous Integrated Boost Volumetric Modulated Arc Therapy on the Outcome of Locally Advanced Rectal Cancer Patients

PURPOSE

Evaluating the outcome of pre-operative simultaneous integrated boost volumetric modulated arc therapy (SIB-VMAT) concomitant with capecitabine in patients diagnosed with locally advanced rectal cancer (LARC) at King Faisal Specialist Hospital and Research Centre (KFSH&RC), Riyadh, Saudi Arabia, during the period January 2013-December 2019.

RESULTS

A total of 134 patients were enrolled. The median age at diagnosis was 59 years. All patients received pre-operative concurrent chemo-radiation therapy (CCRT) using SIB-VMAT with oral capecitabine. Neoadjuvant chemotherapy was administered prior to CCRT in 32 patients (23.9%). The dose of radiation was 55 Gy in 94 patients (70.1%), while 40 patients (29.9%) received 50 Gy. All patients completed the CCRT treatment without breaks. No records of acute and late grade III and IV toxicities. Curative surgery was performed in all patients with a median interval of 11 (6-52) weeks between the end of CCRT and the date of surgery. No reported 30-day postoperative mortality and no grade III and IV Clavien-Dindo complications. PCR was reported in 26 patients (19.4%), while pathologically negative nodes (pN0) were achieved in 103 patients (76.9%). Adjuvant chemotherapy was utilized in 57 patients (42.5%). The 5-year local recurrence-free survival (LRFS), disease-free survival (DFS), and overall survival (OS) were 93.2%, 67.1%, and 87.3%, respectively. Only tumor regression grade (TRG) was significantly correlated with LRFS, (p value 0.043). On multivariate analysis, only TRG and achievement of pN0 were significantly correlated with DFS (p value < 0.001).

CONCLUSION

Dose escalation utilization (SIB-VMAT) in the pre-operative treatment of LARC is well tolerated and provides effective local control.

Radiation hematologic toxicity prediction for locally advanced rectal cancer using dosimetric and radiomics features

BACKGROUND

Hematologic toxicity (HT) is a common adverse tissue reaction during radiotherapy for rectal cancer patients, which may lead to various negative effects such as reduced therapeutic effect, prolonged treatment period and increased treatment cost. Therefore, predicting the occurrence of HT before radiotherapy is necessary but still challenging.

PURPOSE

This study proposes a hybrid machine learning model to predict the symptomatic radiation HT in rectal cancer patients using the combined demographic, clinical, dosimetric, and Radiomics features, and ascertains the most effective regions of interest (ROI) in CT images and predictive feature sets.

METHODS

A discovery dataset of 240 rectal cancer patients, including 145 patients with HT symptoms and a validation dataset of 96 patients (63 patients with HT) with different dose prescription were retrospectively enrolled. Eight ROIs were contoured on patient CT images to derive Radiomics features, which were then, respectively, combined with the demographic, clinical, and dosimetric features to classify patients with HT symptoms. Moreover, the survival analysis was performed on risky patients with HT in order to understand the HT progression.

RESULTS

The classification models in ROIs of bone marrow and femoral head exhibited relatively high accuracies (accuracy = 0.765 and 0.725) in the discovery dataset as well as comparable performances in the validation dataset (accuracy = 0.758 and 0.714). When combining the two ROIs together, the model performance was the best in both discovery and validation datasets (accuracy = 0.843 and 0.802). In the survival analysis test, only the bone marrow ROI achieved statistically significant performance in accessing risky HT (C-index = 0.658, P = 0.03). Most of the discriminative features were Radiomics features, and only gender and the mean dose in Irradvolume was involved in HT.

CONCLUSION

The results reflect that the Radiomics features of bone marrow are significantly correlated with HT occurrence and progression in rectal cancer. The proposed Radiomics-based model may help the early detection of radiotherapy induced HT in rectal cancer patients and thus improve the clinical outcome in future.

Preoperative Radiotherapy with a Simultaneous Integrated Boost Compared to Chemoradiotherapy for cT3-4 Rectal Cancer: Long-Term Results of a Multicenter Randomized Study

BACKGROUND

Preoperative chemoradiotherapy (CRT) is the standard treatment for T3-4 rectal cancer. Here, we compared image-guided and intensity-modulated RT (IG-IMRT) with a simultaneous integrated boost (SIB) (instead of concomitant chemotherapy) versus CRT in a multi-centric randomized trial.

METHODS

cT3-4 rectal cancer patients were randomly assigned to receive preoperative IG-IMRT 46 Gy/23 fractions plus capecitabine 825 mg/m² twice daily (CRT arm) or IG-IMRT 46 Gy/23 fractions with an SIB to the rectal tumor up to a total dose of 55.2 Gy (RTSIB arm).

RESULTS

A total of 174 patients were randomly assigned between April 2010 and May 2014. Grade 3 acute toxicities were 6% and 4% in the CRT and RTSIB arms, respectively. The mean fractional change in SUVmax at 5 weeks after completion of preoperative RT were -55.8% (±24.0%) and -52.9% (±21.6%) for patients in the CRT arm and RTSIB arm, respectively (p = 0.43). The pathologic complete response rate was 24% with CRT compared to 14% with RTSIB. There were no differences in 5-year overall survival (OS), progression-free survival (PFS) or local control (LC).

CONCLUSIONS

The preoperative RTSIB approach was not inferior to CRT in terms of metabolic response, toxicity, OS, PFS and LC, and could be considered an available option for patients unfit for fluorouracil-based CRT.

A case report of typhlitis during novel use of ropidoxuridine-capecitabine-radiotherapy for treatment-naïve rectal cancer

BACKGROUND

Rectal carcinomas are tumors that arise from the last 12 cm of the large intestine closest to the anus. They generally have a modest prognosis exacerbated by a high local recurrence rate if radiosensitizing chemotherapy is not given during radiotherapy. This case report discusses the clinical trial treatment of a patient with rectal adenocarcinoma by a new ropidoxuridine-capecitabine-radiotherapy combination. This case report is novel due to the patient's participation in an accelerated titration phase I clinical trial and the resultant rare adverse event of treatment-related sigmoid typhlitis.

CASE PRESENTATION

The patient was an 82-year-old female who noticed hematochezia and change in stool caliber over a period of 3 months. A rectal mass was identified by biopsy as a microsatellite stable adenocarcinoma. A planned total neoadjuvant treatment involved eight cycles of leucovorin calcium (folinic acid)-fluorouracil-oxaliplatin (mFOLFOX6) chemotherapy, followed by a clinical trial combination of ropidoxuridine-capecitabine-radiotherapy, prior to definitive surgery. The patient began daily intensity modulated pelvic radiotherapy with concurrent twice-daily oral ropidoxuridine and twice-daily oral capecitabine to be given over 6 weeks. After 14 days of ropidoxuridine-capecitabine-radiotherapy, the patient developed sigmoid typhlitis requiring a 10-day hospitalization and 14-day disruption of treatment. The patient died 27 days after the start of ropidoxuridine-capecitabine-radiotherapy. This adverse event was listed as a definite attribution to the ropidoxuridine-capecitabine treatment; pharmacokinetic and pharmacodynamic data showed low ropidoxuridine metabolite DNA incorporation and high capecitabine metabolite concentration. The accelerated titration phase I clinical trial has been subsequently closed to accrual (NCT04406857).

CONCLUSIONS

We believe this case report demonstrates the decision-making process for terminating a phase I accelerated titration designed clinical trial. The report also presents the rare complication of sigmoid typhlitis as a treatment-attributed adverse event. In this case, a ropidoxuridine-capecitabine combination was used as an investigational radiosensitizing treatment now with a narrower future clinical development pathway.

Neoadjuvant chemoradiotherapy versus neoadjuvant chemotherapy alone for patients with locally advanced rectal cancer: a propensity-score-matched analysis combined with SEER validation

BACKGROUND

Neoadjuvant therapy followed by radical surgery is recommended for locally advanced rectal cancer (LARC). But radiotherapy can cause potential adverse effects. The therapeutic outcomes, postoperative survival and relapse rates between neoadjuvant chemotherapy (N-CT) and neoadjuvant chemoradiotherapy (N-CRT) patients have rarely been studied.

METHODS

From February 2012 to April 2015, patients with LARC who underwent N-CT or N-CRT followed by radical surgery at our center were included. Pathologic response, surgical outcomes, postoperative complications and survival outcomes (including overall survival [OS], disease-free survival [DFS], cancer-specific survival [CSS] and locoregional recurrence-free survival [LRFS]) were analyzed and compared. Concurrently, the Surveillance, Epidemiology, and End Results Program (SEER) database was used to compare OS in an external source.

RESULTS

A total of 256 patients were input into the propensity score-matching (PSM) analysis, and 104 pairs remained after PSM. After PSM, the baseline data were well matched and there was a significantly lower tumor regression grade (TRG) (P < 0.001), more postoperative complications (P = 0.009) (especially anastomotic fistula, P = 0.003) and a longer median hospital stay (P = 0.049) in the N-CRT group than in the N-CT group. No significant difference was observed in OS (P = 0.737), DFS (P = 0.580), CSS (P = 0.920) or LRFS (P = 0.086) between the N-CRT group and the N-CT group. In the SEER database, patients who received N-CT had similar OS in both TNM II (P = 0.315) and TNM III stages (P = 0.090) as those who received N-CRT.

CONCLUSION

N-CT conferred similar survival benefits but caused fewer complications than N-CRT. Thus, it could be an alternative treatment of LARC.

Selecting a TNT Schedule in Locally Advanced Rectal Cancer: Can We Predict Who Actually Benefits?

Many consider the standard of care for locally advanced rectal cancer (LARC) to be preoperative chemoradiotherapy, radical surgery involving a total mesorectal excision, and post-operative adjuvant chemotherapy based on the pathology of the specimen. The poor impact on distant control is a major limitation of this strategy, with metastasis rates remaining in the 25-35% range and recovery after radical surgery leading to reluctance with prescription and inconsistent patient compliance with adjuvant chemotherapy. A second limitation is the low rate of pathologic complete response (pCR) (around 10-15%) despite multiple efforts to potentiate preoperative chemoradiation regimens, which in turn means it is less effective at achieving non-operative management (NOM). Total neoadjuvant treatment (TNT) is a pragmatic approach to solving these problems by introducing systemic chemotherapy at an early timepoint. Enthusiasm for delivering TNT for patients with LARC is increasing in light of the results of published randomized phase III trials, which show a doubling of the pCR rate and a significant reduction in the risk of subsequent metastases. However, there has been no demonstrated improvement in quality of life or overall survival. A plethora of potential chemotherapy schedules are available around the radiotherapy component, which include preoperative induction or consolidation with a range of options (FOLFOXIRI, FOLFOX, or CAPEOX,) and a varying duration of 6-18 weeks, prior to long course chemoradiation (LCCRT) or consolidation NACT following short-course preoperative radiation therapy (SCPRT) using 5 × 5 Gy or LCCRT using 45-60 Gy, respectively. The need to maintain optimal local control is a further important factor, and preliminary data appear to indicate that the RT schedule remains a crucial issue, especially in more advanced tumors, i.e., mesorectal fascia (MRF) invasion. Thus, there is no consensus as to the optimum combination, sequence, or duration of TNT. The selection of patients most likely to benefit is challenging, as clear-cut criteria to individuate patients benefiting from TNT are lacking. In this narrative review, we examine if there are any necessary or sufficient criteria for the use of TNT. We explore potential selection for the individual and their concerns with a generalized use of this strategy.

Long-term results of a phase 2 study of neoadjuvant chemotherapy with molecularly targeted agents for locally advanced rectal cancer

BACKGROUND

We previously reported the feasibility and efficacy of neoadjuvant chemotherapy without radiotherapy for locally advanced rectal cancer. Here, we report the results of a long-term follow-up study.

METHODS

This was a multi-institutional, prospective phase 2 study of patients with locally advanced rectal cancer. Patients received neoadjuvant chemotherapy with molecularly targeted agents before undergoing total mesorectal excision. Six cycles of modified FOLFOX (mFOLFOX6) with bevacizumab were administered to KRAS-mutant patients, and mFOLFOX6 with cetuximab was administered to KRAS-wild-type patients. Here, we report the secondary end points of overall survival, relapse-free survival, and local recurrence rate.

RESULTS

Sixty patients were enrolled in this study. R0 resection was achieved in 98.3% (59/60) patients, and pathological complete response was achieved in 16.7% (10/60) patients. After a median follow-up of 5.4 years, the 5 year overall survival was 81.6%, the 5 year relapse-free survival was 71.7%, and the 5 year local recurrence rate was 12.6%. None of the patients who achieved pathological complete response developed recurrence within 5 years.

CONCLUSIONS

The use of molecularly targeted agents in the neoadjuvant setting for locally advanced rectal cancer has an acceptable prognosis.

Nonoperative management of gastrointestinal malignancies in era of neoadjuvant treatment

Cancers derived from the gastrointestinal (GI) tract are often treated with radical surgery to achieve a cure. However, recent advances in the management of GI cancers involve the use of a combination of neoadjuvant radiation and chemotherapy followed by surgical intervention to achieve improved local control and cure. Interestingly, a small proportion of patients with highly sensitive tumors achieved a pathological complete response (pCR) (no residual tumor cells in the resected specimen) to neoadjuvant chemoradiation therapy (nCRT). The desire for organ preservation and avoidance of surgical morbidity brings the idea of a nonoperative management (NOM) strategy. Because of the different nature of tumor biology, GI cancers present diverse responses to nCRT, ranging from high sensitivity (anal cancer) to low sensitivity (gastric/esophageal cancer). There is an increasing attention to NOM of localized GI cancers; however, without the use of biomarkers/imaging parameters to select such patients, NOM will remain a challenge. Therefore, this review intends to summarize some of the recent updates from the aspect of current nCRT regimens, criteria for patient selection and active surveillance schedules. We also hope to review significant sequelae of radical surgery and the complications of nCRT to clarify the directions for optimization of nCRT and NOM for oncologic outcomes and quality of life.

Implications of recent neoadjuvant clinical trials on the future practice of radiotherapy in locally advanced rectal cancer

Over the last two decades, the standard treatment for locally advanced rectal cancer (LARC) has been neoadjuvant chemoradiotherapy plus total mesorectal excision followed by adjuvant chemotherapy. Total neoadjuvant treatment (TNT) and immunotherapy are two major issues in the treatment of LARC. In the two latest phase III randomized controlled trials (RAPIDO and PRODIGE23), the TNT approach achieved higher rates of pathologic complete response and distant metastasis-free survival than conventional chemoradiotherapy. Phase I/II clinical trials have reported promising response rates to neoadjuvant (chemo)-radiotherapy combined with immunotherapy. Accordingly, the treatment paradigm for LARC is shifting toward methods that increase the oncologic outcomes and organ preservation rate. However, despite the progress of these combined modality treatment strategies for LARC, the radiotherapy details in clinical trials have not changed significantly. To guide future radiotherapy for LARC with clinical and radiobiological evidence, this study reviewed recent neoadjuvant clinical trials evaluating TNT and immunotherapy from a radiation oncologist’s perspective.

Preoperative Chemoradiotherapy With Capecitabine With or Without Temozolomide in Patients With Locally Advanced Rectal Cancer: A Prospective, Randomised Phase II Study Stratified by O6-Methylguanine DNA Methyltransferase Status: KCSG-CO17-02

AIMS

To evaluate the clinical efficacy of adding temozolomide (TMZ) to preoperative capecitabine (CAP)-based chemoradiotherapy in patients with locally advanced rectal cancer (LARC) and validate O⁶-methylguanine DNA methyltransferase (MGMT) methylation status as a predictive marker for TMZ combined regimens.

MATERIALS AND METHODS

LARC patients with clinical stage II (cT3-4N0) or III (cT_anyN+) disease were enrolled. They were stratified into unmethylated MGMT (uMGMT) and methylated MGMT (mMGMT) groups by methylation-specific polymerase chain reaction before randomisation and were then randomly assigned (1:1) to one of four treatment arms: uMGMT/CAP (arm A), uMGMT/TMZ + CAP (arm B), mMGMT/CAP (arm C) and mMGMT/TMZ + CAP (arm D). The primary end point was the pathological complete response (pCR) rate.

RESULTS

Between November 2017 and July 2020, 64 patients were randomised. Slow accrual caused early study termination. After excluding four ineligible patients, 60 were included in the full analysis set. The pCR rate was 15.0% (9/60), 0%, 14.3%, 18.8% and 26.7% for the entire cohort, arms A, B, C and D, respectively (P = 0.0498 between arms A and D). The pCR rate was 9.7% in the CAP group (arms A + C), 20.7% in the TMZ + CAP group (arms B + D), 6.9% in the uMGMT group (arms A + B) and 22.6% in the mMGMT group (arms C + D). Grade 1-2 nausea or vomiting was significantly more frequent in the TMZ + CAP treatment groups (arms B + D) than in the CAP treatment groups (arms A + C, P < 0.001) with no difference in grade 3 adverse events. There were no grade 4 or 5 adverse events.

CONCLUSION

The addition of TMZ to CAP-based chemoradiotherapy tended to improve pCR rates, particularly in those with mMGMT LARC. MGMT status may warrant further investigation as a predictive biomarker for chemotherapeutic agents and radiotherapy.

Preoperative Radiochemotherapy in Rectal Cancer: Is There an Impact of Oxaliplatin on Pathologic Complete Response and Survival Rates under "Real World" Conditions?

This study aimed to evaluate the benefit of additional administration of oxaliplatin during fluorouracil-based neoadjuvant radiochemotherapy (nRCT) in terms of pathologic complete remission (pCR), disease-free survival (DFS), and overall survival (OS) in patients with advanced rectal cancer. Between 2006 and 2021, 669 patients (pts) were diagnosed with locally advanced rectal cancer, of whom a total of 414 pts with nRCT were identified and included in the study. A total of 283 pts were treated by nRCT using concurrent chemotherapy with fluorouracil or capecitabine; 131 pts were treated using a combination of fluorouracil or capecitabine and oxaliplatin. Propensity score matching analyses (PSM) with 114 pts in each group were used to balance the patients' characteristics. OS, DFS, pCR-rate, and potential prognostic factors were compared between the two groups. The median follow-up time was 59.5 weeks in the fluorouracil-group and 43 weeks in the fluorouracil/oxaliplatin group (p = 0.003). After PSM, the pCR-rate (including sustained clinical complete remission) was 27% (31/114 pts) in the fluorouracil/oxaliplatin group and 16% (18/114 pts) in the fluorouracil-group (p = 0.033). There was no difference between these two groups for both 10-year OS and DFS neither before nor after PSM, respectively (OS: 72.6% vs. 55.4%, p = 0.066, and 67.8% vs. 55.1%, p = 0.703, and DFS: 44.8% vs. 46.8%, p = 0.134, and 44.7% vs. 42.3%, p = 0.184). Multivariate analysis identified regression grading according to Dworak grade 4 (HR: 0.659; CI: 0.471-0.921; p = 0.015) and age over 60 years (HR: 2.231; CI: 1.245-4.001; p = 0.007) as independent predictors for OS. In conclusion, the addition of oxaliplatin to fluorouracil during nRCT significantly improved pCR-rate without having an impact on survival.

Enhancement of radiation therapy by indoleamine 2,3 dioxygenase 1 inhibition through multimodal mechanisms

BACKGROUND

Indoleamine 2,3-dioxygenase 1 (IDO1) is an enzyme that converts tryptophan to kynurenine. IDO1 expression is found not only in tumor cells but also in immune cells and is associated with tumor proliferation and immune responses. IDO1 inhibitors and radiation may cooperatively suppress tumor proliferation through the alterations in the Wnt/β-catenin pathway, cell cycle, and immune response. We investigated the antitumor effects of combination therapy of an IDO1 inhibitor, 1-methyl tryptophan (1-MT), and radiation on colorectal cancer.

METHODS

In vitro experiments were conducted using human and murine colon cancer cell lines (HCT116, HT-29, and Colon26). Cell growth inhibition was assessed using a MTS assay and Clonogenic assay. Cells were cultured for 48 h with or without 500 µM 1-MT after exposure to radiation (4 Gy). Cell cycle effects and modulation of Wnt/β-catenin pathway were evaluated using western blot analysis, flow cytometry, RT-PCR. Subcutaneous Colon26 tumors in BALB/c mice were treated by oral 1-MT (6 mg/mL) for 2 weeks and/or local radiation (10 Gy/10 fr). Bromodeoxyuridine (BrdU) incorporation in tumor cells and expression of differentiation markers of immune cells were evaluated using immunohistochemistry.

RESULTS

1-MT and a small interfering RNA against IDO1 suppressed proliferation of all cell lines, which was rescued by kynurenine. Clonogenic assay showed that administration of 1-MT improved radiosensitivity by suppressing the Wnt/β-catenin pathway activated by radiation and enhancing cell cycle arrest induced by radiation. Combination therapy showed a further reduction in tumor burden compared with monotherapies or untreated control, inducing the highest numbers of intratumoral CD3 + and CD8 + T cells and the lowest numbers of Foxp3 + and BrdU-positive tumor cells.

CONCLUSIONS

The combination of 1-MT and radiation suppressed colon cancer cells in vitro and in vivo via multiple mechanisms.

A Phase II Study of Preoperative Chemoradiotherapy with Capecitabine Plus Simvastatin in Patients with Locally Advanced Rectal Cancer

PURPOSE

The purpose of this phase II trial was to evaluate whether the addition of simvastatin, a synthetic 3-hydroxy-3-methylglutaryl coenzyme A reductase inhibitor, to preoperative chemoradiotherapy (CRT) with capecitabine confers a clinical benefit to patients with locally advanced rectal cancer (LARC).

MATERIALS AND METHODS

Patients with LARC (defined by clinical stage T3/4 and/or lymph node positivity) received preoperative radiation (45-50.4 Gy in 25-28 daily fractions) with concomitant capecitabine (825 mg/m2 twice per day) and simvastatin (80 mg, daily). Curative surgery was planned 4-8 weeks after completion of the CRT regimen. The primary endpoint was pathologic complete response (pCR). The secondary endpoints included sphincter-sparing surgery, R0 resection, disease-free survival, overall survival, the pattern of failure, and toxicity.

RESULTS

Between October 2014 and July 2017, 61 patients were enrolled; 53 patients completed CRT regimen and underwent total mesorectal excision. The pCR rate was 18.9% (n=10) by per-protocol analysis. Sphincter-sparing surgery was performed in 51 patients (96.2%). R0 resection was achieved in 51 patients (96.2%). One patient experienced grade 3 liver enzyme elevation. No patient experienced additional toxicity caused by simvastatin.

CONCLUSION

The combination of 80 mg simvastatin with CRT and capecitabine did not improve pCR in patients with LARC, although it did not increase toxicity.

Efficacy and safety of preoperative chemoradiotherapy with S-1 for advanced rectal cancer: a phase II study

Background

Preoperative chemoradiotherapy (CRT) for patients with rectal cancer is not yet established in Japan. We aimed to evaluate the efficacy and safety of preoperative CRT with S-1, a fixed-dose combination of tegafur, gimeracil, and oteracil potassium.

Materials and methods

We conducted a prospective, interventional, non-randomized single-center study. Radiotherapy was administered at a total dose of 45 Gy (1.8 Gy in 25 fractions) for five weeks. S-1 was administered orally for nine weeks (five weeks during and four weeks after radiotherapy) at a dose of 80 mg/m²/day. The endpoint was the pathological complete response (pCR) rate.

Results

Twenty-eight patients were finally enrolled. The following patient characteristics were recorded: clinical Stage (II: n = 12, III: n = 16), median age (66 years, range 40-77 years), male/female ratio (20/8), and lesion site (Ra-Rb:3/Rb:23/Rb-P:2). Preoperative treatment was completed in 27 patients (96%). Treatment abandonment occurred because of diarrhea. Grade 3 or higher adverse events were observed in one (4%) patient with two events. No serious adverse events occurred in the ≥ 70 years group. The response rate was 68% in all patients and 68% among elderly patients. Radical resection was achieved in all patients, including 19 (68%) who underwent sphincter-preserving surgery. The pCR rate was 11% (three patients). The five-year disease-free survival rate was 68%, and the overall survival rate was 82%. Local recurrence occurred in only one patient five years after surgery.

Conclusion

Preoperative CRT with S-1 alone may be a safe and acceptable regimen from the perspective of adverse events and oncological outcomes.

Trial registration

UMIN Clinical Trial Registry: UMIN000013598. Registered 1 April 2014, https://upload.umin.ac.jp/cgi-open-bin/ctr_e/ctr_view.cgi?recpt-no=R000015887.

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.

Strategies to Optimize Treatment for Locally Advanced Rectal Cancer

Neoadjuvant long-course concurrent chemoradiation plus surgery, followed by optional adjuvant chemotherapy, is a standard of care for locally advanced rectal cancer (LARC). However, this traditional approach has several limitations, including low pathological complete response (pCR) (10-25%), high metastasis rate (30-35%), and highly inconsistent compliance with adjuvant chemotherapy (25-75%). Treatment modalities for LARC have dramatically evolved in recent years. Multiple clinical trials have focused on optimizing strategies to achieve a win-win situation for oncologic outcomes and functions. Here, we review the latest studies into optimizing neoadjuvant treatment for LARC.

Serum metabolic traits reveal therapeutic toxicities and responses of neoadjuvant chemoradiotherapy in patients with rectal cancer

Neoadjuvant chemoradiotherapy (nCRT) has become the standard treatment for patients with locally advanced rectal cancer (LARC). Therapeutic efficacy of nCRT is significantly affected by treatment-induced diarrhea and hematologic toxicities. Metabolic alternations in cancer therapy are key determinants to therapeutic toxicities and responses, but exploration in large-scale clinical studies remains limited. Here, we analyze 743 serum samples from 165 LARC patients recruited in a phase III clinical study using untargeted metabolomics and identify responsive metabolic traits over the course of nCRT. Pre-therapeutic serum metabolites successfully predict the chances of diarrhea and hematologic toxicities during nCRT. Particularly, levels of acyl carnitines are linked to sex disparity in nCRT-induced diarrhea. Finally, we show that differences in phenylalanine metabolism and essential amino acid metabolism may underlie distinct therapeutic responses of nCRT. This study illustrates the metabolic dynamics over the course of nCRT and provides potential to guide personalized nCRT treatment using responsive metabolic traits.

Preoperative chemoradiotherapy with capecitabine and triweekly oxaliplatin versus capecitabine monotherapy for locally advanced rectal cancer: a propensity-score matched study

Background

Distant metastasis has been the main failure pattern for locoregionally advanced rectal cancer (LARC) patients, and intensified neoadjuvant chemotherapy has become a popular research topic. The present study aimed to compare the survival outcomes, acute toxicities and surgical complications in LARC patients who received preoperative chemoradiotherapy with triweekly oxaliplatin and capecitabine (triweekly XELOX) or capecitabine.

Methods: Between 2007 and 2017, patients with clinically staged II-III rectal cancer who were treated with preoperative chemoradiotherapy using either triweekly XELOX (oxaliplatin 130 mg/m² plus capecitabine 825 mg/m²) or capecitabine were included. Variables potentially influencing chemotherapy treatment selection were used to generate propensity scores (PS). The association between chemotherapy regimens and survival endpoints, including distant metastasis-free survival (DMFS), overall survival (OS) and disease-free survival (DFS), were evaluated and adjusted with PS. The acute toxicities and surgical complications were also compared.

Results

A total of 810 patients were included in the analysis; 277 (34.2%) patients received triweekly XELOX, and 533 (65.8%) received capecitabine. The pathological complete response (pCR) rates were 20.2 and 19.9% (P = 0.912) for the groups treated with triweekly XELOX and capecitabine, respectively. The 5-year DMFS, OS and DFS with triweekly XELOX versus capecitabine were 75.6% vs. 77.6% (P = 0.555), 79.2% vs. 83.3% (P = 0.101), and 69.9% vs. 73.7% (P = 0.283), respectively. Triweekly XELOX was not associated with an increased risk of severe toxicity during chemoradiotherapy, but it increased the risk of postoperative complications compared to capecitabine. After PS adjustment, the differences between the two groups remained insignificant in pCR rate, survival outcomes, and acute toxicities, and the difference in surgical complications disappeared.

Conclusions

Triweekly XELOX or capecitabine concurrent with neoadjuvant radiotherapy leads to similar long-term survival outcomes, acute toxicities and surgical complications in LARC patients.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12885-022-09855-z.

A phase II study of neoadjuvant capecitabine, oxaliplatin, and irinotecan (XELOXIRI) in patients with locally advanced rectal cancer

Purpose

Addition of perioperative multi-agent chemotherapy to the treatment strategy for locally advanced rectal cancer (LARC) may be a promising option. We conducted a phase II study to evaluate the safety and efficacy of capecitabine combined with oxaliplatin and irinotecan (XELOXIRI) as triplet neoadjuvant chemotherapy in patients with LARC.

Methods

Patients received neoadjuvant irinotecan and oxaliplatin and capecitabine and then underwent total mesorectal excision. The primary study endpoint was the pathological complete response (pCR) rate.

Results

Between June 2013 and December 2016, 55 patients were enrolled in the study. Forty-two (77.8%) of 54 completed the study protocol. The pCR rate was 7.7% (95% CI 3.0% to 18.2%). The 3-year local recurrence rate was 3.9%, the 3-year disease-free survival (DFS) rate was 77.3, and the 3-year overall survival rate was 96.0%.

Conclusion

XELOXIRI neoadjuvant chemotherapy appears to be feasible and efficacious for patients with LARC. Although neoadjuvant XELOXIRI alone did not yield our expected pCR rate, the local recurrence rate, 3-year DFS, and measures of safety met current standards.

Health-related quality of life outcomes after neoadjuvant chemoradiotherapy for rectal cancer in NRG Oncology/NSABP R-04

Background

There has been limited evaluation of health‐related quality of life (HRQOL) in rectal cancer patients receiving neoadjuvant chemoradiotherapy. HRQOL outcomes in the National Surgical Adjuvant Breast and Bowel Project R‐04 trial are examined in this article.

Methods

Between 2004 and 2010, R‐04 patients were invited to enroll in the HRQOL substudy, with questionnaires administered before randomization, after completion of chemoradiotherapy, and 1‐year after surgery. HRQOL measures included: Functional Assessment of Cancer Therapy for colorectal cancer (FACT‐C); Short Form‐36v.2 Vitality scale; a treatment‐specific symptom scale; and the FACT neurotoxicity scale. A 5‐year postsurgery assessment was added to the protocol in 2012. Mixed‐effects models examined neoadjuvant therapy treatment effects in the 1‐year sample and models that explored associations of host factors and treatment impact on 5‐year HRQOL.

Results

A total of 1373 patients completed baseline HRQOL and at least one additional assessment. The average age was 58 years (range, 23–85 years), male (68%), and 59% Stage II. There were no statistically significant differences in HRQOL outcomes by treatment arm, but HRQOL worsened from baseline to postneoadjuvant chemoradiotherapy, with statistically significant effect sizes changes ranging from 0.6 (Vitality) to 0.9 (FACT‐C Trial Outcome Index). Neurotoxicity was greater in the oxaliplatin‐treated groups. Obese/overweight patients had statistically significantly worse FACT‐C Trial Outcome Index scores than did underweight/normal weight groups. At 5 years, younger patients and those with normal baseline weight had statistically significantly better physical function scores and older patients had better mental health outcomes.

Conclusions

HRQOL did not differ across the four R‐04 treatment arms; however, host factors explained significant variation in posttreatment HRQOL. ClinicalTrials.gov: NCT00058474 (https://ClinicalTrials.gov/ct2/show/NCT00058474).

Lay summary

This article reports on the health‐related quality of life (HRQOL) outcomes of patients treated with four different chemotherapy regimens combined with radiation in rectal cancer patients before definitive surgical treatment.

There were no significant differences in HRQOL by treatment regimen, but all patients experienced decreased vitality (energy) and physical functioning. By 1 year after treatment, most patients had returned to pretreatment vitality and physical functioning, with the exception of increased neurotoxicity.

In a subsample of patients assessed at 5 years after surgery, physical function was better in those who at pretreatment were younger, normal weight, and had better performance status. Mental function was better in those who at pretreatment were older and had better performance status.

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Multicenter, Randomized, Phase III Trial of Short-Term Radiotherapy Plus Chemotherapy Versus Long-Term Chemoradiotherapy in Locally Advanced Rectal Cancer (STELLAR)

PURPOSE

To ascertain if preoperative short-term radiotherapy followed by chemotherapy is not inferior to a standard schedule of long-term chemoradiotherapy in patients with locally advanced rectal cancer.

MATERIALS AND METHODS

Patients with distal or middle-third, clinical primary tumor stage 3-4 and/or regional lymph node-positive rectal cancer were randomly assigned (1:1) to short-term radiotherapy (25 Gy in five fractions over 1 week) followed by four cycles of chemotherapy (total neoadjuvant therapy [TNT]) or chemoradiotherapy (50 Gy in 25 fractions over 5 weeks, concurrently with capecitabine [chemoradiotherapy; CRT]). Total mesorectal excision was undertaken 6-8 weeks after preoperative treatment, with two additional cycles of CAPOX (intravenous oxaliplatin [130 mg/m², once a day] on day 1 and capecitabine [1,000 mg/m², twice a day] from days 1 to 14) in the TNT group and six cycles of CAPOX in the CRT group. The primary end point was 3-year disease-free survival (DFS).

RESULTS

Between August 2015 and August 2018, a total of 599 patients were randomly assigned to receive TNT (n = 302) or CRT (n = 297). At a median follow-up of 35.0 months, 3-year DFS was 64.5% and 62.3% in TNT and CRT groups, respectively (hazard ratio, 0.883; one-sided 95% CI, not applicable to 1.11; P < .001 for noninferiority). There was no significant difference in metastasis-free survival or locoregional recurrence, but the TNT group had better 3-year overall survival than the CRT group (86.5% v 75.1%; P = .033). Treatment effects on DFS and overall survival were similar regardless of prognostic factors. The prevalence of acute grade III-V toxicities during preoperative treatment was 26.5% in the TNT group versus 12.6% in the CRT group (P < .001).

CONCLUSION

Short-term radiotherapy with preoperative chemotherapy followed by surgery was efficacious with acceptable toxicity and could be used as an alternative to CRT for locally advanced rectal cancer.

Treatment-Related Coronary Disorders of Fluoropyrimidine Administration: A Systematic Review and Meta-Analysis

Background: Coronary disorders are recognized as the most common manifestation of fluoropyrimidine-related cardiotoxicity in clinical practice. However, there are limited and conflicting data on the incidence and profiles of fluoropyrimidine-related coronary disorders. In this meta-analysis, we aimed to systematically assess the incidence of all-grade and grade 3 or higher fluoropyrimidine-related coronary disorders, and further explore the factors that influence its occurrence.

Methods: Studies reporting the fluoropyrimidine-related coronary disorders were retrieved from a systematic search of English literature in the PubMed, Web of Science, Medline, and Cochrane database from 1 Jan 2001, to 1 Jan 2022. The NIH assessment tool was used to evaluate the quality of each study. The data of basic study characteristics, treatment details, and results of coronary toxicities were extracted. According to the results of the heterogeneity test (I² and p-value statistic), a random-effect model or fixed-effect model was selected for the pooled analysis of the incidence of adverse coronary events. Subgroup analysis was conducted to further explore the risks influencing the occurrence of fluoropyrimidine-related coronary disorders. The stability and publication bias of our results were evaluated by sensitivity analysis and Egger test, respectively.

Results: A total of 63 studies were finally included in our pooled analysis, involving 25,577 patients. The pooled cumulative incidence of all-grade and grade 3 or higher coronary disorders was 2.75% (95% CI 1.89%–3.76%) and 1.00% (95% CI 0.62%–1.47%), respectively. The coronary disorders were most reported as myocardial ischemia (1.28%, 95% CI 0.42%–2.49%) and angina/chest pain (1.1%, 95% CI 0.54%–1.81%). Subgroup analysis revealed that studies in the female-only population seemed to have a lower incidence of fluoropyrimidine-related coronary disorders. The occurrence of adverse coronary events varied among different tumor types. Patients with esophageal cancer have the highest coronary toxicity (6.32%), while those with breast cancer have a relatively lower incidence (0.5%). Coronary disorders induced by 5-FU monotherapy are more frequent than that induced by capecitabine (3.31% vs. 1.21%, p < 0.01). Fluoropyrimidine combination therapy, whether combined with other chemotherapy drugs, targeted therapy drugs, or radiotherapy, significantly increased the incidence of coronary complications (p < 0.01).

Conclusion: This meta-analysis has defined the incidence of fluoropyrimidine-related coronary disorders and depicted its epidemiological profiles for the first time, which may provide a reference for clinical practice in cancer management.

Quality of life in a randomized trial comparing two neoadjuvant regimens for locally advanced rectal cancer-INCAGI004

BACKGROUND

Neoadjuvant chemoradiotherapy (neoCRT) followed by surgery is the standard of care for locally advanced rectal cancer (LARC), but the emergence of different drug regimens may result in different response rates. Good clinical response translates into greater sphincter preservation, but quality of life (QOL) may be impaired after treatment due to chemoradiotherapy and surgical side effects.

OBJECTIVE

To prospectively evaluate the impact of clinical response and surgical resection on QOL in a randomized trial comparing two different neoCRT regimens.

METHODS

Stage II and III rectal cancer patients were randomized to receive neoCRT with either capecitabine (group 1) or 5-Fu and leucovorin (group 2) concomitant to long-course radiotherapy. Clinical downstaging was accessed using MRI 6-8 weeks after treatment. EORTCs QLQ-C30 and CR38 were applied before treatment (T0), after neoCRT (T1), after rectal resection (T2), early after adjuvant chemotherapy (T3), and 1 year after the end of treatment or stoma closure (T4). The Wexner scale was used for fecal incontinence evaluation at T4. A C30SummaryScore (Geisinger and cols.) was calculated to compare QOL results.

RESULTS

Thirty-two patients were assigned to group 1 and 31 to group 2. Clinical downstaging occurred in 70.0% of group 1 and 53.3% of group 2 (p = 0.288), and sphincter preservation was 83.3% in group 1 and 80.0% in group 2 (p = 0.111). No significant difference in QOL was detected when comparing the two treatment groups after neoCRT using QLQ-C30. However, the CR38 module detected differences in micturition problems (15.3 points), gastrointestinal problems (15.3 points), defecation problems (11.8 points), and sexual satisfaction (13.3 points) favoring the capecitabine group. C30SummaryScore detected significant improvement comparing T0 to T1 and deterioration comparing T1 to T2 (p = 0.025). The mean Wexner scale score was 9.2, and a high score correlated with symptoms of diarrhea and defecation problems at T4.

CONCLUSIONS

QOL was equivalent between groups after neoCRT except for micturition problems, gastrointestinal problems, defecation problems, and sexual satisfaction favoring the capecitabine arm after. The overall QOL using the C30SummaryScore was improved after neoCRT, but decreased following rectal resection, returning to basal levels at late evaluation. Fecal incontinence was high after sphincter preservation.

TRIAL REGISTRATION

ClinicalTrials.gov Identifier: NCT03428529.

Hyperfractionation versus Conventional Fractionation of Preoperative Intensity-Modulated Radiotherapy with Oral Capecitabine in Locally Advanced Mid-Low Rectal Cancer: A Propensity Score Matching Study

Purpose

In theory, the hyperfractionated radiotherapy can enhance biological effect dose against tumor and alleviate normal tissue toxicity. This study is to assess the efficacy and safety of preoperative hyperfractionated intensity-modulated radiotherapy (IMRT) with oral capecitabine in patients with locally advanced rectal cancer (LARC).

Methods

We retrospectively screened patients with LARC from January 2015 to June 2016. Patients that received hyperfractionated IMRT or conventional fractionated IMRT were eligible in the hyperfractionation (HF) group or conventional fractionation (CF) group, respectively. The primary outcome was the complete response rate. Secondary outcomes included toxicity, postoperative complications, anus-reservation operation rate, local recurrence and distant metastases rate, overall survival (OS), cancer-specific survival (CSS), and disease-free survival (DFS).

Results

335 patients were included in the analysis. The complete response rate for the hyperfractionated and conventional fractionated IMRT was 20.41% vs. 23.47% (P = 0.583). The anus-reservation operation rate was 68.37% vs. 65.31% (P = 0.649). There were no cases of grade 4 toxicity during radiotherapy; the rate of grade 3 toxicity and postoperative complications was both comparable between groups. However, in the CF group, more patients had a second operation due to complications (0.0% vs. 5.68%, P = 0.011). The cumulative local regional recurrence and distant metastases rates of the HF group and CF group were 5.10% vs. 9.18% (P = 0.267) and 22.45% vs. 24.49% (P = 0.736), respectively. The 5-year OS, CSS, and DFS in the HF group and CF group were 86.45% vs. 73.30% (P = 0.503), 87.34% vs. 75.23% (P = 0.634), and 70.80% vs. 68.11% (P = 0.891), respectively.

Conclusions

The preoperative hyperfractionated IMRT with oral capecitabine, with an acceptable toxicity and favorable response and survival, could reduce the rate of secondary surgery.

SEOM-GEMCAD-TTD clinical guidelines for localized rectal cancer (2021)

The management of localized rectal cancer requires a multidisciplinary approach to optimize outcomes, reduce morbidity and prevent under or overtreatments. While early stages may obtain benefit of local resections without any additional therapies, locally advanced rectal cancer becomes a challenge defining the better sequential strategy of surgery, radiotherapy and chemotherapy. The latest results of international phase III studies have positioned the total neoadjuvant therapy as a potential new standard of care in high risk rectal cancers, however, the best schedule is still not well defined.

Phase I Study of Lenvatinib and Capecitabine with External Radiation Therapy in Locally Advanced Rectal Adenocarcinoma

Background

Neoadjuvant chemoradiation with fluoropyrimidine followed by surgery and adjuvant chemotherapy has been the standard treatment of locally advanced stages II and III rectal cancer for many years. There is a high risk for disease recurrence; therefore, optimizing chemoradiation strategies remains an unmet need. Based on a few studies, there is evidence of the synergistic effect of VEGF/PDGFR blockade with radiation.

Methods

In this phase I, dose-escalation and dose-expansion study, we studied 3 different dose levels of lenvatinib in combination with capecitabine-based chemoradiation for locally advanced rectal cancer.

Results

A total of 20 patients were enrolled, and 19 were eligible for assessment of efficacy. The combination was well tolerated, with an MTD of 24 mg lenvatinib. The downstaging rate for the cohort and the pCR was 84.2% and 37.8%, respectively. Blood-based protein biomarkers TSP-2, VEGF-R3, and VEGF correlated with NAR score and were also differentially expressed between response categories. The NAR, or neoadjuvant rectal score, encompasses cT clinical tumor stage, pT pathological tumor stage, and pN pathological nodal stage and provides a continuous variable for evaluating clinical trial outcomes.

Conclusion

The combination of lenvatinib with capecitabine and radiation in locally advanced rectal cancer was found to be safe and tolerable, and potential blood-based biomarkers were identified.

Clinical Trial Registration

NCT02935309

The Evolving Neoadjuvant Treatment Paradigm for Patients with Locoregional mismatch Repair Proficient Rectal Cancer

OPINION STATEMENT

The standard of care for locally advanced rectal cancer (LARC) has included preoperative chemoradiation, total mesorectal excision surgery and post operative adjuvant chemotherapy based on histopathology. The current therapeutic landscape in LARC has many different options with different directions of travel - depending on the goal of treatment. Enthusiasm for delivering total neoadjuvant therapy (TNT) for patients with locally advanced rectal cancer (LARC) is increasing in the light of recently published randomised phase III trials - RAPIDO and PRODIGE-23. There is a wide diversity of different potential schedules and a multitude of approaches, which include induction neoadjuvant chemotherapy (NACT) with a range of chemotherapy options (CAPEOX, FOLFOX, FOLFOXIRI) and a varying duration of 6-18 weeks, or consolidation NACT. These schedules either precede or follow short-course preoperative radiation therapy (SCPRT) using 5 × 5Gy or long-course chemoradiation (LCCRT) using 45-60Gy respectively. The different strategies of induction and consolidation neoadjuvant chemotherapy have been compared and have similar long-term outcomes, but consolidation chemotherapy may facilitate organ-sparing. The results are driving novel paradigms with both intensification and de-intensification treatment strategies. The ideal combination, sequence or duration of such a TNT approach remains undefined. As yet, there are no robust clinical, genetic, molecular, immune or imaging features (alone or integrated), which either direct or aid these choices. Currently, the selection of neoadjuvant treatment is driven by the impact on avoidance or feasibility of surgery or reducing the risk of metastases rather than prevention of local recurrence. Most believe that TNT will improve overall survival, despite the present lack of evidence. Both the inherent heterogeneity in LARC and the observed range of different responses underline the need for response biomarkers to individually tailor therapy rather than 'a one size fits all' approach.

BRIDGE -1 TRIAL: BReak Interval Delayed surgery for Gastrointestinal Extraperitoneal rectal cancer, a multicentric phase III randomized trial

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The lengthening of the surgical interval has a positive impact on pathological complete response (pCR) rate.

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Lengthening the surgical interval from the end of preoperative chemoradiation is not detrimental to survival outcomes in locally advanced rectal cancer.

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Prospective validation of the impact of surgical interval lengthening on complete response and survival outcomes in a randomized trial.

Design

Methods

Conclusions

Neoadjuvant Therapy for Rectal Cancer

The treatment of locally advanced rectal cancer is challenging and requires a multidisciplinary approach. Neoadjuvant treatment has improved local control by the combination of radiotherapy, surgery, and chemotherapy. However, neoadjuvant treatment has not yet been shown to improve overall survival and is associated with toxicities and late sequelae that impair the quality of life of patients. Currently, different types of neoadjuvant strategies have raised the question about which one is the optimal strategy for rectal cancer treatment. In this article, we explore the different neoadjuvant treatment regimens currently available, their associated benefits and toxicities, and novel approaches in this area.

Predicting response to neoadjuvant chemoradiotherapy in rectal cancer: from biomarkers to tumor models

Colorectal cancer (CRC) is a major contributor to cancer-associated morbidity worldwide and over one-third of CRC is located in the rectum. Neoadjuvant chemoradiotherapy (nCRT) followed by surgical resection is commonly applied to treat locally advanced rectal cancer (LARC). In this review, we summarize current and novel concepts of neoadjuvant therapy for LARC such as total neoadjuvant therapy and describe how these developments impact treatment response. Moreover, as response to nCRT is highly divergent in rectal cancers, we discuss the role of potential predictive biomarkers. We review recent advances in biomarker discovery, from a clinical as well as a histopathological and molecular perspective. Furthermore, the role of emerging predictive biomarkers derived from the tumor environment such as immune cell composition and gut microbiome is presented. Finally, we describe how different tumor models such as patient-derived cancer organoids are used to identify novel predictive biomarkers for chemoradiotherapy (CRT) in rectal cancer.

Cost-effectiveness of Total Neoadjuvant Therapy With Short-Course Radiotherapy for Resectable Locally Advanced Rectal Cancer

IMPORTANCE

Short-course radiotherapy and total neoadjuvant therapy (SCRT-TNT) followed by total mesorectal excision (TME) has emerged as a new treatment paradigm for patients with locally advanced rectal adenocarcinoma. However, the economic implication of this treatment strategy has not been compared with that of conventional long-course chemoradiotherapy (LCCRT) followed by TME with adjuvant chemotherapy.

OBJECTIVE

To perform a cost-effectiveness analysis of SCRT-TNT vs LCCRT in conjunction with TME for patients with locally advanced rectal cancer.

DESIGN, SETTING, AND PARTICIPANTS

A decision analytical model with a 5-year time horizon was constructed for patients with biopsy-proven, newly diagnosed, primary locally advanced rectal adenocarcinoma treated with SCRT-TNT or LCCRT. Markov modeling was used to model disease progression and patient survival after treatment in 3-month cycles. Data on probabilities and utilities were extracted from the literature. Costs were evaluated from the Medicare payer's perspective in 2020 US dollars. Sensitivity analyses were performed for key variables. Data were collected from October 3, 2020, to January 20, 2021, and analyzed from November 15, 2020, to April 25, 2021.

EXPOSURES

Two treatment strategies, SCRT-TNT vs LCCRT with adjuvant chemotherapy, were compared.

MAIN OUTCOMES AND MEASURES

Cost-effectiveness was evaluated using the incremental cost-effectiveness ratio and net monetary benefits. Effectiveness was defined as quality-adjusted life-years (QALYs). Both costs and QALYs were discounted at 3% annually. Willingness-to-pay threshold was set at $50 000/QALY.

RESULTS

During the 5-year horizon, the total cost was $41 355 and QALYs were 2.21 for SCRT-TNT; for LCCRT, the total cost was $54 827 and QALYs were 2.12, resulting in a negative incremental cost-effectiveness ratio (-$141 256.77). The net monetary benefit was $69 300 for SCRT-TNT and $51 060 for LCCRT. Sensitivity analyses using willingness to pay at $100 000/QALY and $150 000/QALY demonstrated the same conclusion.

CONCLUSIONS AND RELEVANCE

These findings suggest that SCRT-TNT followed by TME incurs lower cost and improved QALYs compared with conventional LCCRT followed by TME and adjuvant chemotherapy. These data offer further rationale to support SCRT-TNT as a novel cost-saving treatment paradigm in the management of locally advanced rectal cancer.

Effects of Neoadjuvant Radiotherapy on Postoperative Complications in Rectal Cancer: A Meta-Analysis

Objective

Neoadjuvant radiotherapy (nRT) is an important treatment approach for rectal cancer. The relationship, however, between nRT and postoperative complications is still controversial. Here, we conducted a meta-analysis to evaluate such concerns.

Methods

The electronic literature from 1983 to 2021 was searched in PubMed, Embase, and Web of Science. Postoperative complications after nRT were included in the meta-analysis. The pooled odds ratio (OR) was calculated by the random-effects model. Statistical analysis was conducted by Review Manager 5.3 and STATA 14.

Results

A total of 23,723 patients from 49 studies were included in the meta-analysis. The pooled results showed that nRT increased the risk of anastomotic leakage (AL) compared to upfront surgery (OR = 1.23; 95% CI, 1.07-1.41; p=0.004). Subgroup analysis suggested that both long-course (OR = 1.20, 95% CI 1.03-1.40; p=0.02) and short-course radiotherapy (OR = 1.25, 95% CI, 1.02-1.53; p=0.04) increased the incidence of AL. In addition, nRT was the main risk factor for wound infection and pelvic abscess. The pooled data in randomized controlled trials, however, indicated that nRT was not associated with AL (OR = 1.01; 95% CI 0.82-1.26; p=0.91).

Conclusions

nRT may increase the risk of AL, wound infection, and pelvic abscess compared to upfront surgery among patients with rectal cancer.

The survival impact of preoperative FOLFOX for resectable locally advanced rectal cancer: the R-NAC-01 study

PURPOSE

In this follow-up of the R-NAC-01 study, we assessed the long-term oncological benefit of four courses of modified leucovorin, 5-fluorouracil (FU), and oxaliplatin (mFOLFOX6) chemotherapy before rectal surgery.

METHODS

In this prospective, multicenter study (UMIN 000012559) involving 11 hospitals in Japan, patients with lower rectal cancer underwent four cycles of mFOLFOX6 chemotherapy and subsequent surgery within four to six weeks. The 3-year recurrence-free survival and local recurrence rates were then reported.

RESULTS

Of 41 patients (36 males, 5 females; mean age: 60.8 years old) who received 4 courses of chemotherapy, 40 underwent total mesorectal excision, and 1 underwent total pelvic exenteration. R0 resection was achieved in 40 patients, but none showed a pathological complete response. Twenty-nine patients received adjuvant chemotherapy for an average of 4 months. The 3 year recurrence-free survival and local recurrence rates in patients undergoing curable resection were 72.8% and 8.5%, respectively. cStage III patients with adjuvant chemotherapy had a significantly higher 3 year recurrence-free survival than those without adjuvant chemotherapy (76.6 vs. 40.0%, log-rank p = 0.03).

CONCLUSION

Four courses of mFOLFOX6 chemotherapy before surgery may be a promising treatment strategy for locally advanced rectal cancer. Adjuvant chemotherapy might be needed for cStage III patients, even after four courses of neoadjuvant mFOLFOX6.

Revealing potential immunotherapy targets through analysis of a ceRNA network in human colon adenocarcinoma

BACKGROUND

Microsatellite instability-high (MSI-H) is a special type of human colon adenocarcinoma (COAD) that responds well to immunotherapy. MicroRNAs (miRNAs) and long non-coding RNAs (lncRNAs), which are important members of competing endogenous RNAs (ceRNAs) networks, are involved in the tumorigenesis and development of MSI-H COAD. This study aimed to establish a ceRNA network for MSI in COAD to identify targets and prognostic markers that may explain the effects of immunotherapy.

METHODS

COAD sequencing data were extracted from The Cancer Genome Atlas (TCGA), after which differentially expressed miRNAs, lncRNAs, and mRNAs were determined according to microsatellite status. After building a network based on the ceRNA hypothesis, the relationships between microsatellite status and clinical features were explored. Biological processes in the Gene Ontology (GO) and the Kyoto Encyclopedia of Genes and Genomes (KEGG) databases were analyzed for specific miRNAs, lncRNAs, and mRNAs. Survival analysis was used to identify potential biomarkers.

RESULTS

Based on the inclusion criteria, a total of 363 COAD samples were obtained from TCGA. Strict screening criteria were used to identify differentially expressed RNAs in the MSI-H and microsatellite-stable groups, with 82 miRNAs, 1,280 lncRNAs, and 2121 mRNAs obtained (fold change >2, false discovery rate <0.01). Based on the RNA interaction mechanism, a miRNA-lncRNA-mRNA network was constructed, through which a subnetwork composed of 5 miRNAs was discovered. hsa-miR-31-5p, hsa-miR-302a-3p, hsa-miR-302b-3p, hsa-miR-302d-3p, hsa-miR-3619-5p and the RNAs interaction with them have the potential to become novel targets to change the effect of existing immunotherapy. GO and KEGG analyses showed that these differentially expressed miRNAs, lncRNAs, and mRNAs may play key roles in tumorigenesis, tumor development, and drug efficacy, with natural killer cells potentially becoming the next emerging targets for immunotherapy enhancement. Moreover, survival analysis identified 10 lncRNAs as potential survival markers.

CONCLUSIONS

This study identified novel immunotherapy targets and revealed potential biomarkers for COAD according to microsatellite status.

Is There a Benefit of Oxaliplatin in Combination with Neoadjuvant Chemoradiotherapy for Locally Advanced Rectal Cancer? An Updated Meta-Analysis

BACKGROUND

Neoadjuvant fluoropyrimidine (5FU or capecitabine)-based chemoradiotherapy (CRT) has been considered the standard of care for locally advanced rectal cancer (LARC). Whether addition of oxaliplatin (OXP) will further improve clinical outcomes is still unclear.

METHODS

To identify clinical trials combining oxaliplatin in preoperative CRT or perioperative chemotherapy for LARC published until March 2021, we searched PubMed and the Cochrane Library. We also searched for relevant ASCO conference abstracts. The primary endpoint was disease-free survival (DFS). Data were extracted from every study to perform a meta-analysis using Review Manager (version 5.3).

RESULTS

A total of seven randomized clinical trials (ACCORD-12, CARO-AIO-04, FOWARC, JIAO, NSABP, PETACC-6, and STAR-01) with 5782 stage II or III rectal cancer patients were analyzed, including 2727 patients with OXP + 5FU regimen and 3055 patients with 5FU alone. Compared with the 5FU alone group, the OXP + 5FU regimen improved DFS (HR = 0.90, 95% CI: 0.81-0.99, p = 0.03) and pathologic complete response (pCR) (OR = 1.21, 95% CI: 1.07-1.37, p = 0.002). Patients treated with the OXP + 5FU regimen had significantly less metastatic progression (OR = 0.79; 95% CI, 0.67 to 0.94; p = 0.007). Considering adverse events (AEs), there was more grade 3-4 diarrhea with OXP + 5FU (OR = 2.41, 95% CI: 1.74-3.32, p < 0.00001). However, there were no significant differences grade 3-4 hematologic AEs (OR = 1.16, 95% CI: 0.87-1.57, p = 0.31).

CONCLUSIONS

Our meta-analysis with long-term results from the randomized studies showed a benefit of the addition of OXP + 5FU regiment in terms of DFS, metastatic progression, and pCR rate that did not translate to improved OS.

Multidisciplinary management of early rectal cancer - The role of surgical local excision in current and future clinical practice

The implementation of bowel cancer screening programs has led to a rise in the incidence of early rectal cancer. The combination of increased incidence and the growing interest in organ-sparing treatment options has led to an amplified importance of local excision techniques in treatment strategies for early rectal cancer. In addition, developments in new technologies of single-port surgery have popularized surgical techniques. Although local treatment of early rectal cancer seems promising, a multidisciplinary approach is necessary and awareness of the oncological robustness is warranted to enable shared decision-making. This review illustrates the position of surgical local excision in the treatment of early rectal cancer and reflects on its role in current and future clinical practice.