Neoadjuvant short- or long-term radio(chemo)therapy for rectal cancer: how and who should be treated?

Compare clinical efficacy and safety of neoadjuvant therapy and neoadjuvant chemoradiotherapy for locally advanced rectal cancer: Meta-analysis

BACKGROUND

To compare the efficacy and safety of total neoadjuvant therapy (TNT) and neoadjuvant chemoradiotherapy (nCRT) in the treatment of middle and low locally advanced rectal cancer. Our study will systematically collect and integrate studies to evaluate the ability of these two treatments to improve tumor shrinkage rates, surgical resection rates, tumor-free survival, and severe adverse events.

AIM

To provide clinicians and patients with more reliable treatment options to optimize treatment outcomes and quality of life for patients with locally advanced rectal cancer by comparing the advantages and disadvantages of the two treatment options.

METHODS

A full search of all clinical studies on the effectiveness and safety of TNT and nCRT for treating locally advanced rectal cancer identified in Chinese (CNKI, Wanfang, China Biomedical Literature Database) and English (PubMed, Embase) databases was performed. Two system assessors independently screened the studies according to the inclusion and exclusion criteria. Quality evaluation and data extraction were performed for the included literature. We used RevMan 5.3 software to perform a meta-analysis of the pathologic complete response (pCR) rate, T stage degradation rate, resection 0 (R0) rate, anal grade 3/4 acute toxicity rate, perioperative complications, overall survival (OS), and disease-free survival (DFS) in the TNT and nCRT groups.

RESULTS

Finally, 14 studies were included, six of which were randomized controlled studies. A total of 3797 patients were included, including 1865 in the TNT group and 1932 in the nCRT group. The two sets of baseline data were comparable. The results of the meta-analysis showed that the pCR rate [odds ratio (OR) = 1.57, 95% confidence interval (CI): 1.30-1.90, P < 0.00001], T stage degradation rate (OR = 2.16, 95%CI: 1.63-2.57, P < 0.00001), and R0 resection rate (OR = 1.42, 95%CI: 1.09-1.85, P = 0.009) were significantly greater in the nCRT group than in the nCRT group. There was no significant difference in the incidence of grade 3/4 acute toxicity or perioperative complications between the two groups. The 5-year OS [hazard ratio (HR) = 0.84, 95%CI: 0.69-1.02, P = 0.08] and DFS (HR = 0.94, 95%CI: 0.03-1.39, P = 0.74) of the TNT group were similar to those of the nCRT group.

CONCLUSION

TNT has greater clinical efficacy and safety than nCRT in the treatment of locally advanced rectal cancer.

Comparison of preoperative magnetic resonance imaging with postoperative pathology results in rectal cancer patients undergoing neoadjuvant therapy

BACKGROUND

Locally advanced rectal cancer often requires neoadjuvant treatment (NAT) before surgical intervention. This study aimed to assess the concordance between preoperative magnetic resonance imaging (MRI) findings and postoperative pathology results after NAT in rectal cancer patients.

METHOD

A retrospective analysis of 52 patients who underwent NAT and subsequent surgery at Ankara Bilkent City Hospital between May 2019 and May 2023 was conducted. Demographics, preoperative MRIs, time intervals between NAT, MRI, and surgery, and postoperative pathology were assessed.

RESULTS

The median age of the cohort was 59 years, with a male predominance (76.9%). Tumour T stage (κ = 0.157), lymph node stage (κ = 0.138), and circumferential resection margin (κ = 0.138) concordance showed poor agreement between post-neoadjuvant treatment (PNT) MRI and pathology. PNT MRI demonstrated a limited correlation with postoperative pathology.

CONCLUSIONS

While preoperative MRI is commonly used for restaging after NAT in rectal cancer, our study highlights its limited concordance with postoperative pathology. The sensitivity and specificity metrics, although reported in the literature, should be interpreted alongside concordance assessments for a comprehensive evaluation.

Preoperative short-course radiotherapy followed by consolidation chemotherapy for treatment with locally advanced rectal cancer: a meta-analysis

Background

The addition of consolidation chemotherapy to preoperative short-course radiotherapy during the prolonged interval between the completion of radiation and surgery in locally advanced rectal cancer (LARC) could enhance pathologic response and might act on potential micrometastasis. We performed this meta-analysis to evaluate whether short-course radiotherapy followed by consolidation chemotherapy (SCRT/CCT) could be a neoadjuvant treatment option compared with conventional long-course chemoradiotherapy (LCCRT).

Methods

We searched the PubMed, EMBASE, MEDLINE, and Cochrane Library databases. The primary endpoints were pathological outcomes, and the secondary endpoints included survival rate, sphincter preservation rate, R0 resection rate and toxicity. RevMan 5.3 was used to calculate pooled risk ratio (RRs) and 95% confidence intervals (CIs).

Results

A total of seven eligible studies and 1865 participants were included in this meta-analysis. Compared with the LCCRT, SCRT/CCT increased pathologic complete response (pCR) rate [RR = 1.74, 95% CI (1.41, 2.15), P < 0.01] and led to a lower proportion of patients with adjuvant pathologic tumor stage 3–4 (ypT3-4) disease [RR = 0.88, 95% CI (0.80, 0.97), P = 0.01] or lymph node positive (ypN +) disease [RR = 0.83, 95% CI (0.71, 0.98), P = 0.02]. In addition, the disease-free survival (DFS) was better in SCRT/CCT group [RR = 1.10, 95% CI (1.02, 1.18), P = 0.01], while overall survival rate and toxicity and surgical procedures were similar between two groups.

Conclusion

Based on better pathological outcomes and DFS in SCRT/CCT group, we recommended preoperative short-course radiotherapy followed by consolidation chemotherapy as the optional neoadjuvant treatment for LARC.

Neoadjuvant short-course radiotherapy with consolidation chemotherapy for locally advanced rectal cancer: a systematic review and meta-analysis

BACKGROUND

Short-course radiotherapy with consolidation chemotherapy (SCRT-CCT) has emerged as a promising alternative to the long course chemoradiotherapy (LCRT) regimen in locally advanced rectal cancer management. The systematic review and meta-analysis is aimed at summarizing current evidence on SCRT-CCT and comparing it to LCRT.

MATERIAL AND METHODS

Electronic databases of MEDLINE, Web of Science, and Cochrane library were searched using a predefined search strategy returning 3314 articles. This review included 11 studies (6 randomized trials and 5 non-randomized studies) on SCRT-CCT regimen based on seven different cohorts. Weighted arithmetic means and forest plots were generated to determine summary estimates.

RESULTS

The probability of achieving pathological complete response (pCR) was higher with SCRT-CCT compared to LCRT (risk ratio [RR] = 1.75, 95% confidence interval [CI]: 1.41-2.19). No statistically significant difference in 3-year overall survival (OS) was observed between the two groups (RR= 1.06, 95% CI: 0.98-1.14). The weighted arithmetic mean of 3-year OS and pCR was 83.6% versus 80.9%, and 24.5% versus 13.6% for SCRT-CCT and LCRT, respectively. R0 resection and T-downstaging rates ranged from 69.2-100% to 47-75% for SCRT-CCT, and 71-92.3% and 41-75% for LCRT, respectively. The regimens had similar compliance, postoperative, and late toxicity, however, acute toxicity rates varied primarily due to differences in treatment protocols.

CONCLUSIONS

This review highlights the ability of SCRT-CCT to produce improved tumor response with comparable OS, R0 resection, and T-downstaging at the cost of increased acute toxicity. However, heterogeneity in treatment protocols across studies makes it difficult to provide definitive conclusions regarding the regimen. Several ongoing trials are expected to provide further evidence confirming the findings of RAPIDO trial and detail appropriate SCRT-CCT protocols to improve oncological outcomes, minimize toxicity, and determine its effectiveness as the standard-of-care for locally advanced rectal cancer patients.

Total Neoadjuvant Therapy (TNT) versus Standard Neoadjuvant Chemoradiotherapy for Locally Advanced Rectal Cancer: A Systematic Review and Meta-Analysis

BACKGROUND

Total neoadjuvant therapy (TNT) is a novel approach for locally advanced rectal cancer (LARC), which attempts to deliver both systemic chemotherapy and neoadjuvant chemoradiotherapy prior to surgery. However, its efficacy and safety remain controversial in randomized controlled trials (RCTs). We conducted this meta-analysis to assess such concerns.

MATERIALS AND METHODS

Head-to-head phase II/III RCTs were searched in Embase, PubMed, Web of Science, and the Cochrane Library, as well as other sources. The primary endpoint was pathologic complete response (pCR). Secondary endpoints were disease-free survival (DFS), overall survival (OS), local recurrence-free survival, distant metastasis-free survival, and the R0 resection rate.

RESULTS

Eight phase II/III RCTs involving 2,196 patients with LARC were assessed. The primary analysis demonstrated a statistically significant improvement in the pCR rate for TNT treatment (odds ratio, 1.77; 95% confidence interval [CI], 1.28-2.45; p = .0005). TNT treatment also showed improvements in DFS and OS outcomes compared with standard chemoradiotherapy (hazard ratio [HR], 0.83; 95% CI, 0.72-0.96; p = .03 and HR, 0.88; 95% CI, 0.74-1.05; p = .15). In addition, TNT treatment showed significant efficacy in reducing the risk of distant metastasis (HR, 0.81; 95% CI, 0.68-0.95; p = .012).

CONCLUSION

The overall pCR rate may be improved with TNT compared with standard treatment. The TNT strategy may also improve DFS and OS and reduce the risk of distant metastasis.

IMPLICATIONS FOR PRACTICE

Locally advanced rectal cancer (LARC) is a relatively common disease, with a poor prognosis because of its high metastatic potential. The role of total neoadjuvant therapy (TNT) has always been controversial. This meta-analysis found that TNT in LARC is associated with a significant improvement in overall pathologic complete response rate, disease-free survival, overall survival, and distant metastasis-free survival compared with standard treatment. TNT is a promising strategy for LARC, especially for patients who have little desire for surgery.

The association of age with decline in renal function after low anterior resection and loop ileostomy for rectal cancer: a retrospective cohort prognostic factor study

BACKGROUND

Low anterior resection (LAR) is often performed with diverting loop ileostomy (DLI) for anastomotic protection in patients with rectal cancer. We aim to analyze, if older patients are more prone to a decline in kidney function following creation and closure of DLI after LAR for rectal carcinoma versus younger patients.

METHODS

A retrospective cohort study from a database including 151 patients undergoing LAR for rectal carcinoma with DLI was used. Patients were divided in two age groups (Group A: <65 years, n = 79; Group B: ≥65 years, n = 72). For 123 patients undergoing DLI reversal prognostic factors for an impairment of serum creatinine (SCr) and estimated glomerular filtration rate (eGFR) 3 months after DLI reversal was analyzed using a multivariate linear regression analysis.

RESULTS

SCr before LAR(T₀) was significant higher in Group B (P = 0.04). Accordingly, the eGFR at T₀ in group B was significantly lower (P < 0.001). No patients need to undergo hemodialysis after LAR or DLI reversal. Age and SCr at T₀were able to statistically significant predict an increase in SCr (P<0.001) and eGFR (P=0.001) three months after DLI reversal (The R² for the overall model was .82 (adjusted R² = .68).

CONCLUSION

DLI creation may result in a reduction of eGFR in older patients 3 months after DLI closure. Apart from this, patients do not have a higher morbidity after creation and closure of DLI resulting from LAR regardless of their age.

The 2017 Assisi Think Tank Meeting on rectal cancer: A positioning paper

BACKGROUND AND PURPOSES

To describe current practice in the management of rectal cancer, to identify uncertainties that usually arise in the multidisciplinary team (MDT)'s discussions ('grey zones') and propose next generation studies which may provide answers to them.

MATERIALS AND METHODS

A questionnaire on the areas of controversy in managing T2, T3 and T4 rectal cancer was drawn up and distributed to the Rectal-Assisi Think Tank Meeting (ATTM) Expert European Board. Less than 70% agreement on a treatment option was indicated as uncertainty and selected as a 'grey zone'. Topics with large disagreement were selected by the task force group for discussion at the Rectal-ATTM.

RESULTS

The controversial clinical issues that had been identified within cT2-cT3-cT4 needed further investigation. The discussions focused on the role of (1) neoadjuvant therapy and organ preservation on cT2-3a low-middle rectal cancer; (2) neoadjuvant therapy in cT3 low rectal cancer without high risk features; (3) total neoadjuvant therapy, radiotherapy boost and the best chemo-radiotherapy schedule in T4 tumors. A description of each area of investigation and trial proposals are reported.

CONCLUSION

The meeting successfully identified 'grey zones' and, in the light of new evidence, proposed clinical trials for treatment of early, intermediate and advanced stage rectal cancer.

Surgery for Locally Advanced T4 Rectal Cancer: Strategies and Techniques

Locally advanced T4 rectal cancer represents a complex clinical condition that requires a well thought-out treatment plan and expertise from multiple specialists. Paramount in the management of patients with locally advanced rectal cancer are accurate preoperative staging, appropriate application of neoadjuvant and adjuvant treatments, and, above all, the provision of high-quality, complete surgical resection in potentially curable cases. Despite the advanced nature of this disease, extended and multivisceral resections with clear margins have been shown to result in good oncological outcomes and offer patients a real chance of cure. In this article, we describe the assessment, classification, and multimodality treatment of primary locally advanced T4 rectal cancer, with a focus on surgical planning, approaches, and outcomes.

Outcomes of neoadjuvant chemoradiotherapy in Japanese locally advanced rectal carcinoma patients

Background

We investigated the efficacy and prognosis of neoadjuvant chemoradiotherapy (NACRT) for Japanese locally advanced rectal carcinoma patients.

Methods

Fifty-seven patients diagnosed with cT3-4 or any cT/cN+ disease using enhanced computed tomography or magnetic resonance imaging from 2002 to 2014 were enrolled. The male/female ratio was 42/15, and the median age was 67 years. Ra/Rb/Rb-P/P was expressed by 6/35/14/2 patients. Histological tumor types were tub1/tub2/por/muc in 22/30/4/1 patients. For NACRT, radiotherapy doses were 40–50.4 Gy chemotherapy consisted of 5′-DFUR, capecitabine, or S1.

Results

All 57 patients received curative surgical treatment. The anal preservation rate was 65.0 %. The ypStage of 0/I/II/IIIa/IIIb was 7/10/25/11/4 cases. The histological antitumor effect (HATE) was ≥grade (G) 2 and G3 in 31 (54.4 %) and 7 (12.3 %) cases, respectively. Postoperative complications occurred in 17 patients and exceeded GIII (Clavien–Dindo classification) in four patients. Recurrence was observed in 19 patients; the primary local recurrence rate was 5.3 %. The 3-year relapse-free survival (RFS) and overall survival (OS) rates were 64.8 and 95.5 %, respectively; the 5-year RFS and OS rates were 60.2 and 61.0 %, respectively. In multivariate analysis, ypN+ was a high-risk factor for distant organ recurrence. As predictive factors regarding the efficacy of NACRT, a neutrophil concentration <70 % and a neutrophil/lymphocyte ratio <3.0 in peripheral blood prior to treatment indicated that NACRT would be significantly more effective.

Conclusions

NACRT was effective in reducing local recurrence but did not suppress distant organ recurrence in Japanese locally advanced rectal carcinoma patients. A further investigation of an extension of the NACRT regimen is required.

Stereotactic body radiotherapy (SBRT) reirradiation for pelvic recurrence from colorectal cancer

BACKGROUND AND OBJECTIVES

When surgery is not adequate or feasible, stereotactic body radiotherapy (SBRT) reirradiation has been used for recurrent cancers. We report the outcomes of a series of patients with pelvic recurrences from colorectal cancer reirradiated with SBRT.

METHODS

The Cyberknife(TM) Robotic Stereotactic Radiosurgery system with fiducial based real time tracking was used. Patients were followed with imaging of the pelvis.

RESULTS

Four women and 14 men with 22 lesions were included. The mean dose was 25 Gy in median of five fractions. The mean prescription isodose was 77%, with a median maximum dose of 32.87 Gy. There were two local failures, with a crude local control rate of 89%. The median overall survival was 43 months. One patient had small bowel perforation and required surgery (Grade IV), two patients had symptomatic neuropathy (1 Grade III) and one patient developed hydronephrosis from ureteric fibrosis requiring a stent (Grade III).

CONCLUSIONS

Local recurrence in the pelvis after modern combined modality treatment for colorectal cancer is rare. However it presents a therapeutic dilemma when it occurs; often symptomatic and eventually life threatening. SBRT can be a useful non-surgical modality to control pelvic recurrences after prior radiation for colorectal cancer.

Multidisciplinary treatment of rectal cancer in 2014: where are we going?

In the present review we discuss the recent developments and future directions in the multimodal treatment of locally advanced rectal cancer, with respect to staging and re-staging modalities, to the current role of neoadjuvant chemo-radiation and to the conservative and more limited surgical approaches based on tumour response after neoadjuvant combined therapy. When initial tumor staging is considered a high accuracy has been reported for T pre-treatment staging, while preoperative lymph node mapping is still suboptimal. With respect to tumour re-staging, all the current available modalities still present a limited accuracy, in particular in defining a complete response. The role of short vs long-course radiotherapy regimens as well as the optimal time of surgery are still unclear and under investigation by means of ongoing randomized trials. Observational management or local excision following tumour complete response are promising alternatives to total mesorectal excision, but need further evaluation, and their use outside of a clinical trial is not recommended. The preoperative selection of patients who will benefit from neoadjuvant radiotherapy or not, as well as the proper identification of a clinical complete tumour response after combined treatment modalities,will influence the future directions in the treatment of locally advanced rectal cancer.

Could preoperative short-course radiotherapy be the treatment of choice for localized advanced rectal carcinoma?

Short-course preoperative radiotherapy (RT) is widely used in northern Europe for locally advanced resectable rectal cancer, but its role in the era of advanced imaging techniques is uncertain. Here, we reviewed articles and abstracts on SCRT published from 1974 through 2013 with the goal of identifying patients who might be best suited for short-course RT. We included relevant articles comparing surgery with or without preoperative radiation published before and after the advent of total mesorectal excision. We also analyzed two randomized trials directly comparing short-course RT with conventionally fractionated chemoradiation (the Polish Colorectal Study Group and the Trans-Tasman Radiation Oncology Group) that compared short-course RT with conventional chemoradiotherapy. We conclude from our review that short-course RT can be generally applied for operable rectal cancer and produces high rates of pelvic control with acceptable toxicity; it reduces local recurrence rates but does not increase overall survival. SCRT seems to be best used for tumors considered "low risk," i.e., those that are >5 cm from the anal margin, without circumferential margin involvement, and involvement of fewer than 4 lymph nodes. Whether sequential chemotherapy can further improve outcomes remains to be seen, as does the best time for surgery (immediately or 6-8 weeks after RT). We further recommend that selection of patients for short-course RT should be based on findings from magnetic resonance imaging or transrectal ultrasonography.

Colorectal cancer

More than 1·2 million patients are diagnosed with colorectal cancer every year, and more than 600,000 die from the disease. Incidence strongly varies globally and is closely linked to elements of a so-called western lifestyle. Incidence is higher in men than women and strongly increases with age; median age at diagnosis is about 70 years in developed countries. Despite strong hereditary components, most cases of colorectal cancer are sporadic and develop slowly over several years through the adenoma-carcinoma sequence. The cornerstones of therapy are surgery, neoadjuvant radiotherapy (for patients with rectal cancer), and adjuvant chemotherapy (for patients with stage III/IV and high-risk stage II colon cancer). 5-year relative survival ranges from greater than 90% in patients with stage I disease to slightly greater than 10% in patients with stage IV disease. Screening has been shown to reduce colorectal cancer incidence and mortality, but organised screening programmes are still to be implemented in most countries.

Performance of gadofosveset-enhanced MRI for staging rectal cancer nodes: can the initial promising results be reproduced?

OBJECTIVES

A previous study showed promising results for gadofosveset-trisodium as a lymph node magnetic resonance imaging (MRI) contrast agent in rectal cancer. The aim of this study was to prospectively confirm the diagnostic performance of gadofosveset MRI for nodal (re)staging in rectal cancer in a second patient cohort.

METHODS

Seventy-one rectal cancer patients were prospectively included, of whom 13 (group I) underwent a primary staging gadofosveset MRI (1.5-T) followed by surgery (± preoperative 5 × 5 Gy) and 58 (group II) underwent both primary staging and restaging gadofosveset MRI after a long course of chemoradiotherapy followed by surgery. Nodal status was scored as (y)cN0 or (y)cN+ by two independent readers (R1, R2) with different experience levels. Results were correlated with histology on a node-by-node basis.

RESULTS

Sensitivity, specificity and area under the receiver operating characteristics curve (AUC) were 94%, 79% and 0.89 for the more experienced R1 and 50%, 83% and 0.74 for the non-experienced R2. R2's performance improved considerably after a learning curve, to an AUC of 0.83. Misinterpretations mainly occurred in nodes located in the superior mesorectum, nodes located in between vessels and nodes containing micrometastases.

CONCLUSIONS

This prospective study confirms the good diagnostic performance of gadofosveset MRI for nodal (re)staging in rectal cancer.

KEY POINTS

• Gadofosveset-enhanced MRI shows high performance for nodal (re)staging in rectal cancer. • Gadofosveset MRI may facilitate better selection of patients for personalised treatment. • Results can be reproduced by non-expert readers. • Experience of 50-60 cases is required to achieve required expertise level. • Main pitfalls are nodes located between vessels and nodes containing micrometastases.