Impact of age on efficacy of postoperative oxaliplatin-based chemotherapy in patients with rectal cancer after neoadjuvant chemoradiotherapy

Postoperative Adjuvant Treatment Strategy for Locally Advanced Rectal Cancer after Neoadjuvant Treatment

Background

Neoadjuvant (chemo) radiotherapy is used as a standard treatment for locally advanced rectal cancer (LARC), but there is no general consensus on either the efficacy of postoperative adjuvant chemotherapy in patients with LARC after neoadjuvant treatment and surgery, or whether the addition of oxaliplatin to adjuvant chemotherapy provides survival benefits.

Methods

We performed a meta-analysis of data from the PubMed and Embase databases. We included patients with LARC who received neoadjuvant (chemo) radiotherapy and curative surgery. Overall survival (OS), disease-free survival (DFS), toxicity, and compliance were analyzed in the oxaliplatin/fluorouracil- (OX/FU-) based group compared with the FU-based group, and in the chemotherapy group compared with the observation group.

Results

Twenty studies were included in the analysis. Our results indicated that adjuvant chemotherapy prolonged OS (hazard ratio [HR] = 0.78, 95%CI = 0.67–0.91) in patients with LARC treated with neoadjuvant (chemo) radiotherapy and surgery compared with those in the observation group. Subgroup analysis showed the same results in both the ypStage II and ypStage III groups. Compared with those in the observation group, patients in the chemotherapy group also showed an increase in DFS (HR = 0.75, 95%CI = 0.60–0.93). No significant increase was observed in OS (HR = 1.04, 95%CI = 0.87–1.24) or DFS (HR = 0.98, 95%CI = 0.76–1.27) when oxaliplatin was added to FU-based adjuvant chemotherapy, as compared with the FU-based treatment, and subgroup analysis also indicated no survival benefits in the clinical stage II, clinical stage III, ypStage II, and ypStage III groups.

Conclusions

For patients with LARC who have already received neoadjuvant (chemo) radiotherapy and curative surgery, adjuvant chemotherapy improves OS over that in the observation group. Adding oxaliplatin to FU-based adjuvant chemotherapy does not confer survival benefits beyond those from FU-based adjuvant chemotherapy.

Impact of age on the efficacy of oxaliplatin in the preoperative chemoradiotherapy and adjuvant chemotherapy of rectal cancer: a post hoc analysis of the CAO/ARO/AIO-04 phase III trial

Background

The German rectal cancer trial CAO/ARO/AIO-04 has shown a significant benefit in 3-year disease-free survival (DFS) of adding oxaliplatin to a standard preoperative 5-fluorouracil (5-FU)-based chemoradiotherapy (CRT) and adjuvant chemotherapy in patients with locally advanced rectal cancer. The use of oxaliplatin as adjuvant treatment in elderly patients with colon cancer is controversial. We therefore investigated the impact of age on clinical outcome in the CAO/ARO/AIO-04 phase III trial.

Patients and methods

We carried out a post hoc analysis of the CAO/ARO/AIO-04 phase III trial evaluating primary and secondary end points according to age. Patient and tumor characteristics, NCI CTC adverse events grades 3-4 (version 3.0), dose intensities as well as survival and recurrence data were analyzed in three specified age groups (<60, 60-70, and ≥70 years). The influence of age as a continuous variable on DFS was modeled using a subpopulation treatment effect pattern plot (STEPP) analysis.

Results

A total of 1232 patients were assessable. With the exception of Eastern Cooperative Oncology Group status (P < 0.001), no differences in patient and tumor characteristics were noticed between age groups. Likewise, toxicity pattern, dose intensities of CRT and surgical results were similar in all age groups. After a median follow-up of 50 months, in patients aged <60 years a significant benefit of adding oxaliplatin to 5-FU-based CRT and adjuvant chemotherapy was observed for local (P = 0.013) and systemic recurrences (P = 0.023), DFS (P = 0.011), and even overall survival (OS; P = 0.044). The STEPP analysis revealed improved hazard ratios for DFS in patients aged 40-70 years compared with elderly patients treated with oxaliplatin.

Conclusion

The addition of oxaliplatin significantly improved DFS and OS in younger patients aged <60 years with advanced rectal cancer. Patients aged ≥70 years had no benefit.

Clinical Trials Number

NCT00349076.

Treatment of Rectal Cancer in Older Adults

PURPOSE OF REVIEW

Rectal cancer is predominantly a disease of older adults but current guidelines do not incorporate the associated specific challenges leading to wide variation in the delivery of cancer care to this subset of population. Here, we will review the current data available regarding the management of rectal cancer in older adults.

RECENT FINDINGS

The greatest challenge arises in the management of stage II/III disease as it involves tri-modality treatment that can be harder to tolerate by frail older patients. Response to neoadjuvant treatment is being used as a new marker to tailor further therapy and possibly avoid surgery. Oxaliplatin can be omitted from the adjuvant treatment without compromising outcomes. Physicians should perform geriatric assessment utilizing many validated tools available to help predict treatment tolerability and outcomes in older adults that can help personalize subsequent management. Most older adults can undergo standard therapy for stages I, II, or III rectal cancer with curative intent. Increasing evidence suggests that patients with a clinical complete response to neoadjuvant treatment may be observed closely with the possibility of avoiding surgery. Studies are evaluating alternate systemic treatments for advanced metastatic disease with the hope of maintaining quality of life without compromising cancer outcomes.

Management of locally advanced rectal cancer in the elderly: a critical review and algorithm

Colorectal cancer incidence and death rates have been declining over the past 10 years. However, it remains the second leading cause of death in men ages 60-79 and the third leading cause of death in men over 80 and in women over 60 years old. However, there is little data specific to the treatment of the elder patient, since few of these patients are included in trials. With the advent of improved therapies, there are many alternative options available. Still, no definitive consensus or guidelines have been defined for this particular patient population. The goal of this study is to review the literature on the management of rectal cancer in the elderly and to propose treatment algorithms to help the oncology team in treatment decision-making.

Effect of Comorbidities in Stage II/III Colorectal Cancer Patients Treated With Surgery and Neoadjuvant/Adjuvant Chemotherapy: A Single-Center, Observational Study

BACKGROUND

Comorbidity has a detrimental effect on cancer survival, however, it is difficult to disentangle its direct effect from its influence on treatment choice. In this study we assessed the effect of comorbidity on survival in patients who received standard treatment for resected stage II and III colorectal cancer (CRC).

PATIENTS AND METHODS

In total, 230 CRC patients, 68 rectal (29.6%) and 162 colon cancer (70.4%) treated with surgical resection and neoadjuvant/adjuvant chemotherapy from December 2002 to December 2009 at Humanitas Cancer Center were retrospectively reviewed. The key independent variable was the Charlson Comorbidity Index (CCI) score, measured as a continuous variable. The differences between groups for categorical data were tested using the χ² test. Actuarial survival curves were generated using the Kaplan-Meier method.

RESULTS

Median follow-up was 113 (range, 8.2-145.0) months. Median age was 63 (range, 37-78) years. In univariate analysis CCI score was significantly associated with poorer disease-free survival (hazard ratio [HR], 1.65; 95% confidence interval [CI], 1.52-1.80; P < .001), and overall survival (OS; HR, 1.55; 95% CI, 1.41-1.71; P < .001). Factors associated with poorer outcome also included (stage III vs. stage II, P < .029) and age (age >70 vs. ≤70 years, P < .001). After adjusting for these factors, a significant negative prognostic role of CCI score was still observed (adjusted HR for OS, 1.59; 95% CI, 1.43-1.76; P < .001).

CONCLUSION

Among CRC patients who underwent surgical resection and chemotherapy, a higher CCI score was associated with poorer outcome and might predict long-term survival.

Fluorouracil-based neoadjuvant chemoradiotherapy with or without oxaliplatin for treatment of locally advanced rectal cancer: An updated systematic review and meta-analysis

To measure the safety and efficacy of oxaliplatin (OX) application in neoadjuvant chemoradiotherapy (CRT) for locally advanced rectal cancer (LARC), EMBASE, PubMed, Cochrane Library, and Web of Science were used for a literature search. Cochrane's risk of bias tool of randomized controlled trials (RCTs) was used for quality evaluation. The statistical analyses were performed using RevMan 5.3. In addition, 95% confidence intervals (CIs) and pooled risk ratios (RRs) were calculated. Seven RCTs were included in our meta-analysis. After adding OX to fluoropyrimidine (FU), a marginal significant improvement in disease-free survival was noted compared with FU alone (RR = 0.89, 95% CI: 0.78–1.00; P = 0.05). Neoadjuvant CRT with OX significantly decreased the distant metastasis rate (RR = 0.79, 95% CI: 0.67–0.94, P = 0.007). However, no improvement in the local recurrence rate (RR = 0.86, 95% CI: 0.68–1.08; P = 0.19) was noted. In addition, neoadjuvant CRT with OX also significantly increased the pathologic complete response (RR = 1.24, 95% CI: 1.02–1.51; P = 0.03). Grade 3–4 acute toxicity and grade 3–4 diarrhea was considerably higher for OX/FU compared with FU alone. In conclusion, the use of OX on the basis of FU/capecitabine in preoperative CRT is feasible. LARC patients are likely to benefit from CRT regimens with OX.

The differences on efficacy of oxaliplatin in locally advanced colon cancer between mucinous and nonmucinous adenocarcinoma

Until now, it remains unclear how to best use the histological subtype in clinical practice. This study aimed to compare differences in the efficacy of postoperative chemotherapy among different histological subtypes of colon adenocarcinomas. Using the Surveillance, Epidemiology, and End Results‐Medicare database, 51,200 patients with stage II or III primary colon carcinomas who underwent resection for curative intent between 1992 and 2008 were included. The survival benefit was evaluated using a Cox proportional hazards model, interaction analyses, and propensity score‐matched techniques. There was no significant difference in survival for low‐risk stage II mucinous adenocarcinoma (MA) or nonmucinous adenocarcinoma (NMA) between 5‐FU and oxaliplatin‐treated groups (P = 0.387 for MA, P = 0.629 for NMA). Patients with high‐risk stage II NMA who received the oxaliplatin chemotherapy regimen had significantly improved cancer‐specific survival (CSS) compared with the 5‐FU group (P = 0.004), while those with MA saw no improvement (P = 0.690). For stage III tumors, patients with NMA who received the oxaliplatin chemotherapy regimen had significantly improved CSS compared with the 5‐FU group (P < 0.001), while those with MA saw no improvement (P = 0.300). There were significant interactions between chemotherapy regimen and histological subtype. For patients with resected colon cancer who received 5‐FU‐based postoperative chemotherapy, oxaliplatin chemotherapy prolongs CSS for stage III and high‐risk stage II NMA. Conversely, there was no similar improvement with addition of oxaliplatin for patients with stage III or stage II MA.

What has preoperative radio(chemo)therapy brought to localized rectal cancer patients in terms of perioperative and long-term outcomes over the past decades? A systematic review and meta-analysis based on 41,121 patients

We asked what preoperative radiotherapy/chemoradiotherapy (PRT/PCRT) has brought to patients in terms of perioperative and long-term outcomes over the past decades. A systematic review and meta-analysis was conducted using PubMed, Embase and Web of Science databases. All original comparative studies published in English that were related to PRT/PCRT and surgical resection and which analyzed survival, postoperative and quality of life outcomes were included. Data synthesis and statistical analysis were carried out using Stata software. Data from 106 comparative studies based on 80 different trials enrolling 41,121 patients were included in our study. Based on our overall analyses, PRT/PCRT significantly improved patients' local recurrence-free survival (LRFS), but neither overall survival (OS) nor metastasis-free survival (MFS) showed improvement. In addition, PRT significantly increased the postoperative morbidity and mortality but PCRT did not have a significant effect. Furthermore, PRT/PCRT significantly increased the risk of postoperative wound complications but not anastomotic leakage and bowel obstruction. Our comprehensive subgroup analyses further supported the aforementioned results. Meanwhile, long-term anorectal symptoms (impaired squeeze pressures, use of pads, incontinence and urgency) and erectile dysfunction were also significantly increased in patients after PRT/PCRT. The benefits of PRT/PCRT as applied over the last several decades have not been sufficient to improve OS. Metastases of primary tumor and postoperative adverse effects were the two primary obstacles for an improved OS. In fact, the greatest advantage of PRT/PCRT is still local tumor control and a significantly improved LRFS.