Comparison of long course and short course preoperative radiotherapy in the treatment of locally advanced rectal cancer: a systematic review and meta-analysis

Abstract

Background: rectal cancer (RC) is one of the most prevalent malignancies worldwide and different preoperative radiotherapies may lead to different outcomes. This meta-analysis aimed to compare the effectiveness of long-course (LC) and shortcourse radiotherapy (SC), with or without chemotherapy, for locally advanced rectal cancer. Methods: studies published up to March 31 st 2018 were retrieved from PubMed, Medline, Cochrane and EMABSE. Randomized control or consort control trials that reported the outcomes of short or long course radiotherapy were eligible. Either a fixed or random effects model was used to access the overall combined risk estimates. Results: sixteen studies with a total of 2,773 RC patients were included in the analysis. There were no significant differences between LC and SC therapies with regard to the following: pathological complete response (PCR) (I 2 = 78%, p < 0.05, RR = 0.54, 95% CI: 0.26-1.10); tumor downstaging (I 2 = 79%, p < 0.05, RR = 0.83, 95% CI: 0.58-1.17); local recurrences (I 2 = 22%, p = 0.27, RR = 0.55, 95% CI: 0.26-1.16); distant metastases (I 2 = 29%, p = 0.22, RR = 1.03, 95% CI: 0.77-1.37); mortality (I 2 = 0%, p = 0.78, RR = 0.95, 95% CI: 0.78-1.15) and serious late toxicity (I 2 = 74%, p = 0.01, RR = 1.10, 95% CI: 0.37-3.26). In the subgroup analysis, LC had a better PCR and tumor downstaging rate compared with SC in the RCT subgroup. Besides, LC also presented a better PCR rate compared with SC without chemotherapy. Conclusions: LC and SC are both effective in the preoperative treatment of RC with regard to PCR, tumor downstaging, local recurrences, distant metastases, mortality and serious late toxicity. Furthermore, chemotherapy may enhance the efficacy of preoperative treatment.

Multidisciplinary management of elderly patients with rectal cancer: recommendations from the SICG (Italian Society of Geriatric Surgery), SIFIPAC (Italian Society of Surgical Pathophysiology), SICE (Italian Society of Endoscopic Surgery and new technologies), and the WSES (World Society of Emergency Surgery) International Consensus Project

“…Similarly to other meta-analyses, PLCCRT increased the rate of grade 3-4 acute toxicity (RR = 0.13, P < 0.00001) and pCR (RR = 0.15, P = 0.003). Similar outcomes have been found in a recent systematic review and meta-analysis performed by the Chinese group of Yu et al [ 92 ]. Sixteen studies with a total of 2.773 rectal cancer patients were included in the pooled analysis.…”

Efficacy of conversion therapy on initially unresectable locally advanced rectal cancer

“…Second, our patients received consolidation chemotherapy during the interval of chemoradiotherapy and TME, which had been confirmed efficient in improving the pCR rate in previous studies [13,17]. Third, comparing to the former group which used short-course radiotherapy with 3 cycles of FOLFOX4, our R0 resection rate was slightly higher, probably because the concurrent chemotherapy may enhance the efficacy of preoperative treatment [18], even though no direct evidence was found to demonstrate the superiority of conventionally fractionated radiation to short-course radiation [16,19]. Finally, the addition of oxaliplatin to fluorouracil-based chemotherapy has been reported to be more efficient in preoperative treatment [8,9].…”

Comparing neoadjuvant long-course chemoradiotherapy with short-course radiotherapy in rectal cancer

“…This may be because the SC group received more preoperative chemotherapy. A previous meta-analysis found that LC presented a better pCR rate compared with the SC without chemotherapy, meaning that chemotherapy may enhance the efficacy of preoperative treatment [ 12 ]. Another randomized phase III study by Bujko et al [ 13 ] compared patients receiving radiotherapy (5 × 5 Gy) and three cycles of FOLFOX4 with those receiving 50.4 Gy in 28 fractions combined with two 5-day cycles of bolus 5-Fu 325 mg/ m 2 /day and leucovorin 20 mg/m 2 /day during the first and fifth week of irradiation along with five infusions of oxaliplatin 50 mg/m 2 once weekly.…”