Short-course radiotherapy followed by chemotherapy before total mesorectal excision (TME) versus preoperative chemoradiotherapy, TME, and optional adjuvant chemotherapy in locally advanced rectal cancer (RAPIDO): a randomised, open-label, phase 3 trial

Circulating tumour DNA in predicting and monitoring survival of patients with locally advanced rectal cancer undergoing multimodal treatment: long-term results from a prospective multicenter study

BACKGROUND

Neoadjuvant chemoradiotherapy (nCRT) is the standard for locally advanced rectal cancer (LARC). However, distant metastasis remains the primary cause of treatment failure. Early identification of high-risk individuals for personalized treatment may offer a solution. Circulating tumour DNA (ctDNA) could assist in this process.

METHODS

From September 2017 to June 2019, the study prospectively recruited 113 patients with LARC (cT3-4N0M0 or cTanyN + M0) who underwent nCRT followed by radical surgery across 8 tertiary centers. ctDNA was analysed using large-panel targeted sequencing at baseline, during nCRT, pre-surgery, post-surgery, post-adjuvant chemotherapy (ACT), and during annual follow-ups for 3 years.

FINDINGS

We analysed 103 tissue and 669 plasma samples from 103 patients. With a median 53-month follow-up, significantly worse progression-free survival (PFS) and overall survival (OS) were observed if median variant allele frequency (mVAF) of baseline ctDNA per patient was ≥0.5% (PFS, HR 4.39, p < 0.001; OS, HR 5.61, p = 0.004) or ctDNA was still detectable two weeks into nCRT (PFS, HR 7.63, p < 0.001; OS, HR 5.08, p < 0.001). Furthermore, when compared to the low-risk (C1) group (characterized by "ctDNA undetected during nCRT with baseline mVAF <0.5%" or "ctDNA undetected during nCRT with TMB (tumour mutational burden) ≥20/Mb"), the high-risk (C2) group (characterized by "ctDNA detected during nCRT" or "baseline mVAF ≥0.5% with TMB <20/Mb") showed significantly worse long-term outcomes (3 y-PFS, 55.9% vs. 94.2%; 3 y-OS, 79.4% vs. 100%). The ctDNA clearance during nCRT, baseline mVAF, and TMB may be effective prognostic indicators.

INTERPRETATION

Our findings reaffirm the clinical monitoring value of ctDNA and demonstrate the strong prognostic value of baseline ctDNA and its early clearance status in patients with LARC undergoing nCRT. This highlights the potential of dynamic ctDNA monitoring as actionable stratified indicators to guide personalized neoadjuvant treatment strategies.

FUNDING

This work was supported by the Major Grants Program of Beijing Science and Technology Commission (No. D171100002617003) and the National High Level Hospital Clinical Research Funding (2022-PUMCH-C-005).

Intensity-modulated radiation therapy can reduce acute toxicities in long-course neoadjuvant radiation therapy combined with S-1 for locally advanced rectal cancer

BACKGROUND

The purpose of this study was to compare outcomes and adverse events between three-dimensional conformal radiation therapy (3D-CRT) and intensity-modulated radiation therapy (IMRT) in patients undergoing long-course neoadjuvant radiation therapy (NA-RT) for locally advanced rectal adenocarcinoma (LARC).

METHODS

We retrospectively analyzed a total of 47 consecutive patients who received NA-RT for LARC between January 2011 and September 2022. Seven and 40 patients were diagnosed with clinical stages II and III, respectively. The prescribed dose per fraction was 1.8 Gy for total doses of 45 or 50.4 Gy. Seventeen and 30 patients received 3D-CRT and IMRT, respectively. NA-RT was delivered with concurrent chemotherapy of oral administration of S-1.

RESULTS

Planned NA-RT was completed without any treatment interruption in 43 of the 47 patients. Two patients experienced treatment interruption, and two patients discontinued due to grade ≥ 3 toxicities. No significant differences were observed between patients receiving 3D-CRT and IMRT in local control, progression-free survival, and overall survival (P = 0.488, 0.259, and 0.636, respectively). Patients receiving IMRT showed significantly fewer non-hematological grade ≥ 2 acute toxicities than those receiving 3D-CRT (33.3% vs. 70.6%, P = 0.018). In addition, patients who received IMRT tended to have less intestinal toxicity of grade ≥ 2 than those who received 3D-CRT (P = 0.057).

CONCLUSION

IMRT significantly reduced grade ≥ 2 acute toxicities without compromising oncologic outcomes compared to 3D-CRT. Therefore, IMRT may be considered as a current standard treatment in the total neoadjuvant therapy era.

Digestive cancers: mechanisms, therapeutics and management

Cancers of the digestive system are major contributors to global cancer-associated morbidity and mortality, accounting for 35% of annual cases of cancer deaths. The etiologies, molecular features, and therapeutic management of these cancer entities are highly heterogeneous and complex. Over the last decade, genomic and functional studies have provided unprecedented insights into the biology of digestive cancers, identifying genetic drivers of tumor progression and key interaction points of tumor cells with the immune system. This knowledge is continuously translated into novel treatment concepts and targets, which are dynamically reshaping the therapeutic landscape of these tumors. In this review, we provide a concise overview of the etiology and molecular pathology of the six most common cancers of the digestive system, including esophageal, gastric, biliary tract, pancreatic, hepatocellular, and colorectal cancers. We comprehensively describe the current stage-dependent pharmacological management of these malignancies, including chemo-, targeted, and immunotherapy. For each cancer entity, we provide an overview of recent therapeutic advancements and research progress. Finally, we describe how novel insights into tumor heterogeneity and immune evasion deepen our understanding of therapy resistance and provide an outlook on innovative therapeutic strategies that will shape the future management of digestive cancers, including CAR-T cell therapy, novel antibody-drug conjugates and targeted therapies.

Simultaneous integrated boost to lateral pelvic lymph nodes during chemoradiotherapy in high-risk rectal cancer

BACKGROUND

Preoperative chemoradiotherapy combined with total mesorectal excision (TME) is a standard treatment for locally advanced rectal cancer (LARC). However, lateral pelvic lymph nodes (LPLNs) are often inadequately treated with standard regimens. This study examines the treatment and postoperative outcomes in LARC patients receiving a simultaneous integrated boost (SIB) for LPLNs during long-course chemoradiotherapy.

METHODS

This retrospective study included high-risk LARC patients (UICC, "Union Internationale Contre le Cancer", stage III) treated with preoperative chemoradiotherapy and SIB to LPLNs. Radiotherapy was delivered to the primary tumor and elective volumes with 50.4 Gy in 28 fractions, and an SIB with a median dose of 60.2 Gy was administered to clinically positive LPLNs. TME quality and postoperative complications were assessed using MERCURY and Clavien-Dindo, respectively. Time-to-event data were analyzed according to Kaplan-Meier.

RESULTS

Between 2019 and 2023, 27 patients with high-risk LARC and LPLN metastases were treated with chemoradiotherapy. After a median follow-up of 19 months, 2‑year overall survival was 80%, disease-free survival 80%, and local control of dose-escalated lymph nodes 100%. Three patients were managed nonoperatively after a clinical complete response on endoscopy and imaging. Of the 22 patients who had surgery, only one had complications higher than Clavien-Dindo grade I; TME was graded as MERCURY I in 73%.

DISCUSSION AND CONCLUSION

The SIB approach for LPLNs in LARC is feasible, does not increase postoperative morbidity, and achieves excellent local control. This study supports the consideration of dose-escalated radiotherapy for LPLNs to address high local recurrence risks.

Curative-Intended Management of Synchronous Esophageal and Rectal Cancer-A Systematic Literature Review

PURPOSE

Synchronous esophageal (EC) and rectal carcinoma (RC) is a rare and challenging condition, particularly in curative-intended treatment. Especially locally advanced tumors may not be suitable for primary resection and require individual multimodal treatment. This review examines curative-intended management of synchronous EC and RC.

MATERIAL AND METHODS

A systematic literature search across five electronic databases according to the PRISMA guideline was conducted. Individual patient data was analyzed, including two additional cases from our institution.

RESULTS

We identified 9 relevant cases from 1552 results. Additionally, two male patients (62 and 65 years old) from our institution were included. Both received 5-fluorouracil/cisplatin-based chemoradiotherapy (CRT) for EC. Sequential short-course radiation (SCRT) for RC was performed in one patient. After complete response (CR) in both tumors, no consecutive surgery was performed. He underwent resection for local recurrence of RC 11 months later and is currently considered as disease-free (30 months follow-up). The second patient underwent primary resection of RC and had early progression following resection of EC. We found that most patients had advanced EC (8/11), with the majority receiving neoadjuvant (5/11) or definitive treatment (3/11). Locally advanced RC was diagnosed in 5/11 patients, primarily treated with sequential resection. Pyrimidine-based systemic treatment was common. Four relapses and two deaths were reported, but median follow-up was 11 (range 1.5-30) months only.

CONCLUSION

The review suggests that neoadjuvant multimodal approaches may offer curative potential for synchronous EC and RC, with individualized treatment protocols adapted from single-cancer protocols. Nevertheless, data on long-term outcome is limited.

Longitudinal circulating tumor DNA monitoring in predicting response to short-course radiotherapy followed by neoadjuvant chemotherapy and camrelizumab in locally advanced rectal cancer: data from a Phase Ⅲ clinical trial (UNION)

This study, conducted as part of a multicenter phase III clinical trial, aimed to assess the utility of circulating tumor DNA (ctDNA)-based minimal residual disease (MRD) in comparing the efficacy of short-course and long-course chemoradiotherapy (CRT) for locally advanced rectal cancer (LARC). A total of 244 plasma samples from 79 LARC patients undergoing neoadjuvant therapy (NAT) before surgery were collected at various time points. Targeted deep sequencing using a novel MRD panel was performed. During NAT, ctDNA levels declined significantly. Baseline ctDNA-MRD status did not correlate significantly with treatment response. Notably, compared to long-course radiotherapy, microsatellite instability increased significantly after short-course radiotherapy (shortRT). Additionally, ctDNA negativity or lower levels were significantly associated with pathological complete response (pCR). Clearance of ctDNA and MRD after shortRT correlated significantly with pCR. A predictive model based on ctDNA-MRD, combined with carcinoembryonic antigen (CEA), outperformed models using only MRD or only CEA in predicting pCR/non-pCR. These findings provide insights into NAT for LARC and highlight ctDNA-based MRD assessment's potential in tailoring treatment strategies, emphasizing the need for personalized approaches.

Economic Evaluation of 'Watch and Wait' Following Neoadjuvant Therapy in Locally Advanced Rectal Cancer: A Systematic Review

BACKGROUND

Owing to multimodal treatment and complex surgery, locally advanced rectal cancer (LARC) exerts a large healthcare burden. Watch and wait (W&W) may be cost saving by removing the need for surgery and inpatient care. This systematic review seeks to identify the economic impact of W&W, compared with standard care, in patients achieving a complete clinical response (cCR) following neoadjuvant therapy for LARC.

METHODS

The PubMed, OVID Medline, OVID Embase, and Cochrane CENTRAL databases were systematically searched from inception to 26 April 2024. All economic evaluations (EEs) that compared W&W with standard care were included. Reporting and methodological quality was assessed using the Consolidated Health Economic Evaluation Reporting Standards (CHEERS), BMJ and Philips checklists. Narrative synthesis was performed. Primary and secondary outcomes were (incremental) cost-effectiveness ratios and the net financial cost.

RESULTS

Of 1548 studies identified, 27 were assessed for full-text eligibility and 12 studies from eight countries (2016-2024) were included. Seven cost-effectiveness analyses (complete EEs) and five cost analyses (partial EEs) utilized model-based (n = 7) or trial-based (n = 5) analytics with significant variations in methodological design and reporting quality. W&W showed consistent cost effectiveness (n = 7) and cost saving (n = 12) compared with surgery from third-party payer and patient perspectives. Critical parameters identified by uncertainty analysis were rates of local and distant recurrence in W&W, salvage surgery, perioperative mortality and utilities assigned to W&W and surgery.

CONCLUSION

Despite heterogenous methodological design and reporting quality, W&W is likely to be cost effective and cost saving compared with standard care following cCR in LARC. Clinical Trials Registration PROSPERO CRD42024513874.

Hypofractionated Preoperative Radiation Therapy for Soft Tissue Sarcoma: A Systematic Review

PURPOSE

Hypofractionated radiation therapy is being used more frequently for many common cancer sites. Conventionally fractionated radiation therapy treatment regimens have remained the standard of care when radiation therapy is indicated for soft tissue sarcoma (STS). The aim of this study was to systematically review published data on the use of preoperative hypofractionated radiation therapy as part of a curative treatment paradigm in patients with STS. Herein, we summarize current evidence for the use of hypofractionated radiation therapy in the preoperative treatment of STS.

METHODS AND MATERIALS

We conducted a database search for prospectively or retrospectively collected data on patients with a diagnosis of STS treated with hypofractionated radiation therapy. Studies evaluating STS of all histologic subtypes affecting extremities or trunks were included in the search. Articles were screened by 2 independent reviewers for inclusion in this review. Patient, treatment, toxicity, and outcome data were recorded and collated from selected studies.

RESULTS

Twenty-five articles are included in this review. Nine prospective trials have been published since 2020. Dose fractionations range from 25 to 40 Gy in 5 fractions or 28-42.75 Gy in 8-15 fractions. Local control and overall survival outcomes are consistent with historical data for conventionally fractionated radiation therapy. Acute toxicity and wound complication rates are in keeping with acceptable results. Late toxicity data are limited and require longer follow-up. Rates of pathologic complete response are promising across all studies.

CONCLUSIONS

There is a growing body of evidence supporting hypofractionation as safe and effective in the preoperative treatment of STS. This review highlights potential areas that could be further investigated to optimize preoperative treatment for STS.

The Influence of Pelvic Bone Dose-volume Parameters on Bone Marrow Suppression During Radiation Therapy in Patients With Stage I to III Rectal Cancer Based on Real-world Data

Purpose

The aim of this study was to evaluate the effect of pelvic bone dose-volume parameters on bone marrow suppression during radiation therapy (RT) in patients with rectal cancer stage I to III disease receiving either neoadjuvant radiation therapy (neo-RT) or curative-intent radiation therapy (cur-RT).

Methods and Materials

This was a retrospective study with data mined from an electronic medical record review at a single institution. Between January 2016 and September 2022, patients with rectal cancer who consecutively received neo-RT or cur-RT in our department were included. The data collected included complete baseline peripheral blood counts and hematologic toxicity (HT) data collected during RT. The radiation dose-volume parameters of 3 pelvic bone marrow subsites (iliac bone marrow [IBM], lumbosacral bone marrow, and lower pelvis bone marrow) were collected. The primary endpoint was grade ≥ 2 HT (HT2+), including leukopenia, neutropenia, anemia, thrombocytopenia, and total HTs. Logistic regression was employed to analyze the associations of HT2+ with dosimetric parameters and clinicopathologic characteristics. Receiver operating characteristic curves and the area under the curve (AUC) were generated to verify the prediction efficacy of the pelvic bone dose-volume parameters combined with clinicopathologic indices.

Results

A total of 130 patients with stage I to III rectal cancer with complete clinical data were included. During neo-RT and cur-RT, 57 (43.8%) of these patients experienced HT2+. Multivariate analysis revealed that gender, the IBM-Dmean, the IBM-V15, and the IBM-V40 were significantly associated with grade 2+ leukopenia (P < .05), and the AUC of gender combined with the IBM-Dmean, the IBM-V15, and the IBM-V40 in predicting grade 2+ leukopenia was 0.834. The optimal cutoff values were an IBM-Dmean = 2692.75 cGy, an IBM-V15 = 86.65%, and an IBM-V40 = 20.75%. Patients who received oxaliplatin-containing concurrent chemotherapy (ChT) regimens were more likely to experience grade 2+ thrombocytopenia (P = .054). The AUC of concurrent ChT regimens in predicting grade 2+ thrombocytopenia was 0.678. Female gender was significantly associated with grade 2+ anemia and total HT2+ status.

Conclusions

Among patients with rectal cancer stage I to III disease who received neo-RT or cur-RT, female patients with higher IBM-Dmean, IBM-V15, and IBM-V40 were more likely to experience grade 2+ leukopenia, and oxaliplatin-containing concurrent ChT regimens were identified as a potential factor for increasing the incidence of grade 2+ thrombocytopenia.

Risk factors for local recurrence in patients with clinical stage II/III low rectal cancer: A multicenter retrospective cohort study in Japan

Background

Identifying risk factors for local recurrence (LR) is pivotal in optimizing rectal cancer treatment. Total mesorectal excision (TME) and lateral lymph node dissection (LLND) are the standard treatment for advanced low rectal cancer in Japan. However, large-scale studies to evaluate risk factors for LR are limited.

Methods

Data from 1479 patients with clinical stage II/III low rectal cancer below the peritoneal reflection, surgically treated between January 2010 and December 2011 across 69 hospitals, were analyzed. Fine-Gray multivariable regression modeling was used to identify risk factors associated with LR. Two models were developed: one using preoperative factors only, and the other incorporating operative and postoperative factors.

Results

Across the entire cohort, the 5-year cumulative incidence of LR was 12.3% (95% confidence interval, 10.7-14.1). The multivariable analysis associated LR with various preoperative (body mass index, distance from anal verge, cN category, and histological subtype), treatment-related (neoadjuvant therapy, and LLND), and postoperative (pT, pN, and resection margins) risk factors. For patients without neoadjuvant treatment, LR risk was unacceptably high with two or three preoperative risk factors (body mass index ≥25 kg/m2, distance from anal verge ≤4.0 cm, non-well/moderately differentiated adenocarcinoma). The 5-year cumulative incidence of LR was 24.7% in patients treated without LLND and 22.9% in patients treated with LLND.

Conclusion

This large multicenter cohort study identified some risk factors for LR in the setting where upfront TME was predominant, offering insights to optimize rectal cancer treatment.

Palliative pelvic radiotherapy for symptomatic frail or metastatic patients with rectal adenocarcinoma: A systematic review

BACKGROUND

Locally advanced rectal cancer can cause severe symptomatic pelvic morbidity such as pain, haemorrhage or bowel obstruction for frail or metastatic patients, which are often unfit to undergo surgery or intense systemic treatment. The most frequent radiation schedule is 25 Gy/ 5f but the optimal dose is yet to determine. Our aim was to conduct a systematic review on the efficacy and toxicity of the published radiation schedules of palliative rectal cancer.

METHODS

Systematic literature of the Medline, Embase and Cochrane library databases were performed throughout the year 2023. Published articles on palliative external beam radiation therapy (EBRT) for locally advanced or metastatic rectal cancer reporting on symptom palliation, overall survival (OS) and quality of life (QOL) were eligible for inclusion.

RESULTS

Thirteen studies were included, five of them were prospective studies. There were large variations in radiation schedules, associated chemotherapy and palliative care. Pooled overall symptomatic response rate was 71 %, while response rates were respectively 90 %, 85 %, and 84 % for pain, bleeding, and pelvic symptoms. Acute toxicities were mostly mild genitourinary or gastrointestinal.

CONCLUSIONS

Short course palliative radiation for LARC for frail or metastatic patients is efficient for symptom palliation with few adverse effects. A short course EBRT with an integrated IMRT boost on the tumoral volume could be of interest.

Treatment Pattern and Outcome of Locally Advanced Rectal Cancer in Resource-Constrained Countries: Experience at Tikur Anbessa Specialized Hospital, Addis Ababa, Ethiopia

PURPOSE

Management of locally advanced rectal cancer (LARC) includes neoadjuvant chemoradiotherapy (NACRT) followed by total mesorectal excision. Recently, total neoadjuvant treatment (TNT) has gained attention. In developing countries, patients with rectal cancer often present at advanced stages. This study assesses treatment patterns and outcomes in LARC at a largest referral center in Ethiopia.

MATERIALS AND METHODS

A cross-sectional study was conducted on 100 patients with LARC treated at Tikur Anbessa Specialized Hospital from January 2020 to September 2022.

RESULTS

The median age at diagnosis was 45.5 years (range, 20-86), with 51% male. Of the patients, 81% had no previous oncologic treatment and 75.3% was discussed in a multidisciplinary tumor board. Up-front surgery was planned for 44.4% of patients, whereas 22.2% and 8.6% were assigned to TNT and NACRT, respectively. Among 81 treatment-naïve patients, 79 were triaged for surgery, but only 47 (59.5%) underwent surgery, achieving an 89.9% R0 resection rate. Of 36 up-front planned surgeries, 35 proceeded as planned, whereas only 12 of 43 (28%) planned after neoadjuvant treatment underwent surgery. Neoadjuvant chemotherapy (NACT) was given to 37% of patients, with 16.7% (5 of 30) undergoing subsequent surgery. Radiotherapy was given to 24.2% of participants, with 56.25% undergoing surgery. Short-course radiotherapy (SCRT) was given to two patients. Only 14.8% completed all planned treatments, with radiation waiting time (median, 10 months) being the main impediment.

CONCLUSION

Timely administration of neoadjuvant treatment is not possible in most resource-limited settings. Because of better treatment completion, up-front surgery looks a more viable option than NACT in these situations. Extended waiting time for radiotherapy can be mitigated by opting for alternatives like SCRT in selected patients.

FDG-PET/MRI in colorectal cancer care: an updated systematic review

PURPOSE

Since its introduction in 2011, FDG-PET/MRI has been advocated as a useful adjunct in colorectal cancer care. However, gaps and limitations in current research remain. This systematic review aims to review the current literature to quantify the utility of FDG-PET/MRI in colorectal cancer care.

METHODS

An up-to-date review was performed on the available literature between 2000 and 2023 on PubMed, EMBASE, Medline, databases. All studies reporting on the use of FDG-PET/MRI in colorectal cancer care were analyzed. The main outcome measures were accuracy in initial staging, restaging, and detection of metastatic disease in both rectal as well as colon cancers. The secondary outcome was comparing the performance of FDG-PET/MRI versus Standard of Care Imaging (SCI). Finally, the clinical significance of FDG-PET/MRI was measured in the change in management resulting from imaging findings.

RESULTS

A total of 22 observational studies were included, accounting for 988 patients. When individually compared to current Standard of Care Imaging (SCI)-MRI pelvis for rectal cancer and thoraco-abdominal contrast CT, PET/MRI proved superior in terms of distant metastatic disease detection. This led to as much as 21.0% change in management. However, the technological limitations of PET/MRI were once again highlighted, suggesting SCI should retain its place as first-line imaging.

CONCLUSION

FDG-PET/MRI appears to be a promising adjunct in staging and restaging of colorectal cancer in carefully selected patients.

The Chinese Society of Clinical Oncology (CSCO): Clinical guidelines for the diagnosis and treatment of colorectal cancer, 2024 update

The 2024 updates of the Chinese Society of Clinical Oncology (CSCO) Clinical Guidelines for the diagnosis and treatment of colorectal cancer emphasize standardizing cancer treatment in China, highlighting the latest advancements in evidence-based medicine, healthcare resource access, and precision medicine in oncology. These updates address disparities in epidemiological trends, clinicopathological characteristics, tumor biology, treatment approaches, and drug selection for colorectal cancer patients across diverse regions and backgrounds. Key revisions include adjustments to evidence levels for intensive treatment strategies, updates to regimens for deficient mismatch repair (dMMR)/ microsatellite instability-high (MSI-H) patients, proficient mismatch repair (pMMR)/ microsatellite stability (MSS) patients who have failed standard therapies, and rectal cancer patients with low recurrence risk. Additionally, recommendations for digital rectal examination and DNA polymerase epsilon (POLE)/ DNA polymerase delta 1 (POLD1) gene mutation testing have been strengthened. The 2024 CSCO Guidelines are based on both Chinese and international clinical research, as well as expert consensus, ensuring their relevance and applicability in clinical practice, while maintaining a commitment to scientific rigor, impartiality, and timely updates.

Total neoadjuvant therapy based on short-course radiotherapy versus standard long-course chemoradiotherapy for locally advanced rectal cancer: a systematic review and meta-analysis of randomized controlled trials

Background

We conducted the meta-analysis to compare the therapeutic effects of total neoadjuvant therapy (TNT) based on short-course radiotherapy followed by consolidation chemotherapy (SCRT/CCT) and long-course chemoradiotherapy (LCCRT) for locally advanced rectal cancer (LARC) according to certain significant randomized controlled trials (RCTs).

Methods

The researchers retrieved several databases, including PubMed, Embase, Web of Science, and the Cochrane Library, to collect all the relevant literature published since the establishment of the databases until July 30, 2024, and then screened to determine the qualified literature and extracted the relevant information. Finally, RevMan 5.4 software was utilized to conduct the meta-analysis for determining the 95% confidence interval (CI) and pooled risk ratio (RR). There were 9 study indicators, including the pathologic complete remission (pCR) rate, tumor downstaging rate, R0 resection rate, sphincter preservation rate, disease-free survival (DFS), overall survival (OS), acute ≥3 grade toxicity rate, surgery complication rate, and distant recurrence rate. When moderate, even severe, heterogeneity was found, a random-effect model was applied; otherwise, a fixed-effect model was used for the analysis.

Results

A total of 6 eligible RCTs and 2259 participants were included in this meta-analysis. Compared with the standard LCCRT, TNT treatment on the basis of SCRT/CCT increased the pCR rate significantly [RR = 1.67, 95% CI (1.36, 2.04), P < 0.00001], especially in ≥ 4 cycles of the CCT arm [RR = 1.77, 95% CI: (1.41-2.23), p < 0.00001], and led to a similar tumor downstaging rate [RR = 0.99, 95% CI (0.85, 1.15), P = 0.92]. Moreover, survival outcomes, distant recurrence rate, and surgical indicators were comparable between the two groups.

Conclusion

For LARC patients, the SCRT/CCT regimen not only has a higher pCR rate, equivalent OS, and comparable additional indicators versus standard LCCRT but also shortens the treatment time, costs less, and improves patients' adherence to the innovative anti-tumor therapy; hence, with the concept of acute toxicity control, it could be further widely and safely utilized, especially in resource-limited settings.

Systematic review registration

https://www.crd.york.ac.uk/prospero/, identifier CRD42024600180.

Long-term outcomes of S-1 and oxaliplatin neoadjuvant chemotherapy with total mesorectal excision and lateral lymph node dissection for rectal cancer

PURPOSE

Chemoradiotherapy (CRT) for rectal cancer is limited by its harmful side effects and its insufficient benefit on lateral lymph node metastases. The purpose of this study was to evaluate the long-term outcomes of S-1 and oxaliplatin with total mesorectal excision (TME) and lateral lymph node dissection (LLND) without radiation for rectal cancer.

METHODS

The inclusion criteria were patients with stage II or III rectal cancer located within 10 cm from the anal verge. Fifty-two patients who underwent neoadjuvant chemotherapy (NAC) followed by TME and LLND were evaluated. The primary endpoint was the 3-year local recurrence. The secondary endpoints were the 3-year rates of relapse-free survival and overall survival. Expected post-NAC and surgical outcomes were prospectively analyzed.

RESULTS

The overall recurrence rate was 15.4%, with eight patients developing distant recurrences. The local recurrence rate was 7.7% (n = 4). Among the 4 patients with local recurrence, 3 (5.8%) patients had central pelvis recurrence, and 1 (1.9%) patient had lateral pelvic recurrence. The 3-year survival rate was 98.1%, and the 3-year relapse-free survival rate was 84.6%. The risk factors for local recurrence were mucinous carcinoma (p = 0.016) and a positive resection margin (p = 0.009). Pathological mesorectal lymph node metastasis and local recurrence were independent risk factors for poor survival.

CONCLUSIONS

Although preoperative chemotherapy and TME with LLND are sufficient to control local recurrence, some cases will require more aggressive chemotherapy with radiation therapy.