Adjuvant chemotherapy and survival outcomes in rectal cancer patients with good response (ypT0-2N0) after neoadjuvant chemoradiotherapy and surgery: A retrospective nationwide analysis

Impact of adjuvant chemotherapy on survival in ypT0-2 N0 rectal cancer

PURPOSE

The role of adjuvant chemotherapy in rectal cancer patients downstaged to ypT0-2 N0 after neoadjuvant chemoradiotherapy (CRT), and surgery is still debated. This study investigates the impact of adjuvant chemotherapy on survival outcomes in this patient population.

METHODS

This retrospective study analyzed hospital records of rectal cancer cases from Shefa Al Orman Cancer Hospital between January 2016 and December 2020, focusing on patients downstaged to ypT0-2 N0 after neoadjuvant CRT and surgery. Patients were divided into two groups based on whether they received adjuvant chemotherapy. Baseline characteristics, DFS, and OS were compared, and survival factors were analyzed using univariate and multivariate Cox regression.

RESULTS

Eighty-five patients met the inclusion criteria; 55 received adjuvant chemotherapy, and 30 did not. The median age was 52, but those receiving adjuvant therapy were younger (47 vs. 60 years, P = 0.006). No significant differences were observed in sex, tumor location, or pathology between groups. Although adjuvant chemotherapy showed a trend toward better 3-year DFS (89.5% vs. 81.9%, P = 0.153) and OS (88.1% vs. 84.6%, P = 0.654), these differences were not statistically significant. Univariate and multivariate analyses confirmed no significant effect of adjuvant chemotherapy on DFS or OS, nor were any other variables significantly associated with survival.

CONCLUSION

Adjuvant chemotherapy did not significantly improve DFS or OS in rectal cancer patients downstaged to ypT0-2 N0 following neoadjuvant CRT and surgery. Further studies are needed to define the role of adjuvant therapy in this group.

Lymph node metastasis following chemoradiotherapy in advanced rectal cancer: ypT2-focused analyses of total mesorectal excision specimens

BACKGROUND

Non-radical management is an option for good responders to neoadjuvant chemoradiotherapy in mid-to-low rectal cancer. This study aimed to analyze risk factors for lymph node metastasis in patients with ypT2 rectal cancer, exploring the possibility of non-radical management.

METHODS

We included patients with ypT2 rectal cancer who received neoadjuvant chemoradiotherapy followed by total mesorectal excision between January 2004 and December 2022. Clinicopathological parameters were evaluated to identify risk factors for lymph node metastasis.

RESULTS

Among the 198 patients, 158 (79.8%) had ypT2N0 and 40 (20.2%) had ypT2N+. In univariable analyses, the risk factors of lymph node metastasis were perineural invasion (48.0% vs. 16.3% without perineural invasion, P < 0.001), female sex (30.0% vs. 14.8% with male sex, P = 0.011), and clinically positive nodes after neoadjuvant chemoradiotherapy (32.6% vs. 16.4% with negative nodes, P = 0.017). These factors were confirmed as independent risk factors in multivariable analyses: perineural invasion (odds ratio [OR]: 4.50; 95% confidence interval [CI]: 1.79-11.29; P < 0.001), female sex (OR: 2.62; 95% CI: 1.24-5.52; P = 0.012) and clinical node involvement after neoadjuvant chemoradiotherapy (OR: 2.28; 95% CI: 1.03-5.05; P = 0.012). The rate of lymph node metastasis in patients with ypT2 rectal cancer without any of these three risk factors was 12.5%.

CONCLUSIONS

This study revealed a high probability of lymph node metastasis in patients with ypT2 rectal cancer, even in the absence of identifiable risk factors. We confirm that lymph node metastasis should be considered in ypT2 rectal cancer.

Small molecule inhibitors as adjuvants in cancer immunotherapy: enhancing efficacy and overcoming resistance

Adjuvant therapy is essential in cancer treatment to enhance primary treatment effectiveness, reduce adverse effects, and prevent recurrence. Small molecule inhibitors as adjuvants in cancer immunotherapy aim to harness their immunomodulatory properties to optimize treatment outcomes. By modulating the tumor microenvironment, enhancing immune cell function, and increasing tumor sensitivity to immunotherapy, small molecule inhibitors have the potential to improve patient responses. This review discusses the evolving use of small molecule inhibitors as adjuvants in cancer treatment, highlighting their role in enhancing the efficacy of immunotherapy and the opportunities for advancing cancer therapies in the future.

The role of adjuvant chemotherapy in rectal cancer patients with ypT0-2N0 after neoadjuvant chemoradiotherapy

Background

Neoadjuvant chemoradiotherapy has emerged as the established treatment for locally advanced rectal cancer. Nevertheless, there remains a debate regarding the necessity of adjuvant chemotherapy for patients with locally advanced rectal cancer who exhibit a favorable tumor response (ypT0-2N0) after neoadjuvant chemoradiotherapy and surgery. Thus, the objective of this study is to investigate the impact of adjuvant chemotherapy on the oncological prognosis of rectal cancer patients who have a good response to neoadjuvant chemoradiotherapy.

Materials and methods

The study was conducted following the Preferred Reporting Items for Systematic Reviews and Meta-Analyses protocol. Articles were searched in the Web of Science, PubMed, and Cochrane Library databases. The primary outcomes assessed were 5-year overall survival, disease-free survival, cancer-specific survival, recurrence-free survival, local recurrence, and distant metastasis. The data was summarized using a random effects model.

Results

A meta-analysis was conducted using 18 retrospective studies published between 2009 and 2023. The studies included 9 from China and 5 from Korea, involving a total of 6566 patients with ypT0-2N0 rectal cancer after neoadjuvant chemoradiotherapy. The pooled data revealed that adjuvant chemotherapy significantly improved 5-year overall survival (OR=1.75, 95% CI: 1.15-2.65, P=0.008), recurrence-free survival (OR=1.73, 95% CI: 1.20-2.48, P=0.003), and reduced distant metastasis (OR=0.68, 95% CI: 0.51-0.92, P=0.011). However, adjuvant chemotherapy did not have a significant effect on disease-free survival, cancer-specific survival, and local recurrence in ypT0-2N0 rectal cancer. Subgroup analysis indicated that adjuvant chemotherapy was beneficial in improving overall survival for ypT1-2N0 rectal cancer (OR=1.89, 95% CI: 1.13-3.19, P=0.003).

Conclusion

The findings of the meta-analysis suggest that adjuvant chemotherapy may provide benefits in terms of oncological outcomes for rectal cancer patients with ypT0-2N0 after neoadjuvant chemoradiotherapy and radical surgery. However, further prospective clinical studies are needed to confirm these findings.

Effect of adjuvant chemotherapy on the oncological outcome of rectal cancer patients with pathological complete response

BACKGROUND

Locally advanced rectal cancer is typically treated using a combination of neoadjuvant chemoradiotherapy and total mesorectal resection. While achieving pathological complete response following neoadjuvant chemoradiotherapy has been recognized as a positive prognostic factor in oncology, the necessity of adjuvant chemotherapy for locally advanced rectal cancer patients with pathological complete response after surgery remains uncertain. The objective of this meta-analysis was to examine the impact of adjuvant chemotherapy on the oncological outcomes of rectal cancer patients who attain pathological complete response after neoadjuvant chemoradiotherapy.

METHODS

This meta-analysis followed the guidelines outlined in the preferred reporting items for systematic review and meta-analysis (PRISMA). The Web of Science, PubMed, and Cochrane Library databases were systematically searched to identify relevant literature.

RESULTS

A total of 34 retrospective studies, including 9 studies from the NCBD database, involving 31,558 patients with pathological complete response rectal cancer, were included in the meta-analysis. The included studies were published between 2008 and 2023. The pooled analysis demonstrated that adjuvant chemotherapy significantly improved overall survival (HR = 0.803, 95% CI 0.678-0.952, P = 0.011), and no heterogeneity was observed (I2 = 0%). Locally advanced rectal cancer patients with pathological complete response who underwent adjuvant chemotherapy exhibited a higher 5-year overall survival rate compared to those who did not receive adjuvant chemotherapy (OR = 1.605, 95% CI 1.183-2.177, P = 0.002). However, the analysis also revealed that postoperative ACT did not lead to improvements in disease-free survival and recurrence-free survival within the same patient population. Subgroup analysis indicated that pathological complete response patients with clinical stage T3/T4, lymph node positivity, and younger than 70 years of age may benefit from adjuvant chemotherapy in terms of overall survival.

CONCLUSIONS

The findings of this meta-analysis suggest that adjuvant chemotherapy has a beneficial effect on improving overall survival among rectal cancer patients with pathological complete response. However, no such association was observed in terms of disease-free survival and recurrence-free survival.

The Conditioning of Adjuvant Chemotherapy for Stage II and III Rectal Cancer Determined by Postoperative Pathological Characteristics in Romania

The management of locally advanced rectal cancer (LARC) suffered changes thanks to the development of improved surgical procedures, radiation delivery, and chemotherapy. Although treatment options improved individually, the optimal order is still debated. Neoadjuvant chemo-radiotherapy followed by total mesorectal excision (TME) has been the "golden standard" for locally advanced rectal cancer. There is no common ground in international guidelines on the indications of adjuvant chemotherapy (ADJCHT), with differences between the American, European, and Japanese guidelines. This paper studies the preferences of Romanian oncologists in prescribing ADJCHT. We conducted a single-institution, retrospective study of all nonmetastatic, ECOG 0-1 LARC patients staged II-III who underwent TME and were admitted to the Oncology or Radiotherapy Department of Colțea Clinical Hospital, Bucharest between January 2017 and March 2021. A total of 186 patients were included in the study. A positive correlation was found between ADJCHT and each of the following: (y)pT > 2, (y)pN > 0, and the presence of perineural invasion (PNI+). A strong positive correlation was found between ADJCHT and the presence of at least one risk factor: (y)pT > 2, (y)pN > 0, PNI+, lymphovascular invasion, positive margins, or tumor grade > 1. Tumor downstaging decreased the risk of metastases in the first 2 years and was associated with the use of neoadjuvant radiotherapy, while adding neoadjuvant chemotherapy increased the chance of nodal downstaging. ADJCHT practice for LARC in Romania follows either NCCN or ESMO guidelines, at the discretion of the oncologist, due to the lack of national guideline.