The current evidence in support of multimodal treatment of locally advanced, potentially resectable esophageal cancer

Neoadjuvant chemoradiotherapy or chemotherapy alone for oesophageal cancer: population-based cohort study

BACKGROUND

Although both neoadjuvant chemoradiotherapy (nCRT) and chemotherapy (nCT) are used as neoadjuvant treatment for oesophageal cancer, it is unknown whether one provides a survival advantage over the other, particularly with respect to histological subtype. This study aimed to compare prognosis after nCRT and nCT in patients undergoing oesophagectomy for oesophageal adenocarcinoma (OAC) or squamous cell carcinoma (OSCC).

METHODS

Data from the National Cancer Database (2006-2015) were used to identify patients with OAC and OSCC. Propensity score matching and Cox multivariable analyses were used to account for treatment selection biases.

RESULTS

The study included 11 167 patients with OAC (nCRT 9972, 89.3 per cent; nCT 1195, 10.7 per cent) and 2367 with OSCC (nCRT 2155, 91.0 per cent; nCT 212, 9.0 per cent). In the matched OAC cohort, nCRT provided higher rates of complete pathological response (35.1 versus 21.0 per cent; P < 0.001) and margin-negative resections (90.1 versus 85.9 per cent; P < 0.001). However, patients who had nCRT had similar survival to those who received nCT (hazard ratio (HR) 1.04, 95 per cent c.i. 0.95 to 1.14). Five-year survival rates for patients who had nCRT and nCT were 36 and 37 per cent respectively (P = 0.123). For OSCC, nCRT had higher rates of complete pathological response (50.9 versus 30.4 per cent; P < 0.001) and margin-negative resections (92.8 versus 82.4 per cent; P < 0.001). A statistically significant overall survival benefit was evident for nCRT (HR 0.78, 0.62 to 0.97). Five-year survival rates for patients who had nCRT and nCT were 45.0 and 38.0 per cent respectively (P = 0.026).

CONCLUSION

Despite pathological benefits, including primary tumour response to nCRT, there was no prognostic benefit of nCRT compared with nCT for OAC suggesting that these two modalities are equally acceptable. However, for OSCC, nCRT followed by surgery appears to remain the optimal treatment approach.

The Optimal Treatment for Resectable Esophageal Cancer: A Network Meta-Analysis of 6168 Patients

The optimal treatment for resectable esophageal cancer remains unclear. This network meta-analysis compares the efficacy of different treatments. PubMed, Embase, and the Cochrane library were systematically screened. Randomized controlled trials comparing the efficacy of different treatments for resectable esophageal cancer were included. Hazard ratios (HR) for overall survival (OS), progression-free survival, or disease-free survival, and odds ratios for locoregional recurrence and distant metastasis rates were identified as the measurements of efficacy. A Bayesian network meta-analysis was performed. In this study, 26 studies were included. Patients received either surgery alone; neoadjuvant chemotherapy (CT), neoadjuvant radiotherapy (RT), or neoadjuvant chemoradiotherapy (CRT) followed by surgery; or surgery followed by adjuvant CT, adjuvant RT, or adjuvant CRT. Neoadjuvant CRT followed by surgery (pooled HR = 0.76, 95% credible interval: 0.67–0.85) and neoadjuvant CT followed by surgery compared with surgery alone were the only two showing statistically confident improvement on OS. Ranking analysis showed that neoadjuvant CRT with surgery was likely to be the best option in terms of efficacy. Therefore, for patients with resectable esophageal cancer, neoadjuvant CRT with surgery is the optimal treatment. Future studies should focus on the optimization of neoadjuvant CRT regimens.

Optimal preoperative neoadjuvant therapy for resectable locally advanced esophageal squamous cell carcinoma

Esophageal squamous cell carcinoma (ESCC) is one of the most common malignancies worldwide, especially in East Asia. ESCC accounts for more than 90% of esophageal cancer. Currently, neoadjuvant therapy in combination with surgical resection is the mainstay of treatment. However, the overall survival rate of patients with locally advanced ESCC is not satisfactory even when treated following the standard treatment guidelines. With neoadjuvant chemoradiotherapy, chemotherapy, or emerging immunotherapy, continuous exploration of efficacy in relation to ESCC is expected to improve overall survival further. Here, we review and summarize current evidence for efficacy of preoperative therapy for locally advanced ESCC.

THUMP domain containing 2 protein possibly induces resistance to cisplatin and 5-fluorouracil in in vitro human esophageal squamous cell carcinoma cells as revealed by transposon activation mutagenesis

BACKGROUND

Although chemotherapy is a core treatment for esophageal cancer, some patients develop drug resistance. Gene screening with transposons (i.e. mobile genetic elements) is a novel procedure for identifying chemotherapy-resistant genes. Transposon insertion can randomly affect nearby gene expression. By identifying the affected genes, candidate genes can be found. The present study aimed to identify cisplatin (CDDP)/5-fluorouracil (5-FU)-resistant genes in in vitro human esophageal squamous cell carcinoma with transposons.

METHODS

After establishing transposon-tagged cells, we obtained CDDP/5-FU-resistant colonies. A polymerase chain reaction and sequencing were used to identify the transposon inserted site and candidate CDDP/5-FU resistant genes. Focusing on one candidate gene, we confirmed CDDP/5-FU resistance by comparing the IC₅₀ between drug-resistant and wild-type cells. Furthermore, we investigated gene expression by a real-time polymerase chain reaction. Finally, we mediated the candidate gene level with small interfering RNA to confirm the resistance.

RESULTS

Thirty-nine candidate genes for CDDP/5-FU resistance were identified. Nineteen were for CDDP resistance and 27 were for 5-FU resistance. Seven genes, THUMP domain-containing protein 2 (THUMPD2), nuclear factor interleukin-3-regulated protein (NFIL3), tyrosine-protein kinase transmembrane receptor 2 (ROR2), C-X-C chemokine receptor type 4 (CXCR4), thrombospondin type-1 domain-containing protein 2 (THSD7B) alpha-parvin (PARVA) and TEA domain transcription factor 1 (TEAD1), were detected as candidate genes in both colonies. Regarding THUMPD2, its expression was downregulated and knocking down THUMPD2 suggested drug resistance in both drugs.

CONCLUSIONS

Thirty-nine candidate genes were identified with transposons. The downregulation of THUMPD2 was suggested to play a role in multidrug resistance in in vitro esophageal squamous cell carcinoma.

The Optimal Chinese Herbal Injections for Use With Radiotherapy to Treat Esophageal Cancer: A Systematic Review and Bayesian Network Meta-Analysis

Ethnopharmacological relevance: Esophageal cancer is one of the most common human cancers, and its incidence is highly endemic in China. The combination of Chinese herbal injections (CHIs) and radiotherapy should be informed by the best available evidence.

Aim of the study: To update and expand on previous work in order to compare and rank the efficacy and safety of CHIs in combination with radiotherapy to treat esophageal cancer.

Materials and Methods: We searched several electronic databases to identify randomized controlled trials (RCTs) regarding CHIs to treat esophageal cancer from their inception to March 15, 2017. In a network meta-analysis (NMA), the bias of the included trials was assessed by two individuals independently in accordance with the Cochrane Handbook for Systematic Reviews of Interventions. Outcomes such as the clinical effectiveness rate, performance status, adverse reactions (ADRs), and survival rate were evaluated. We performed a random-effects NMA to obtain estimates of efficacy and safety outcomes, and we present these estimates as odds ratios (ORs) and corresponding 95% confidence intervals (CIs) calculated via Stata 13.1 and WinBUGS 1.4 software. Furthermore, the surface under cumulative the ranking curve (SUCRA) was used to rank the efficacy and safety of different CHIs in relation to each outcome.

Results: Of 685 identified trials, 55 were eligible for inclusion in the study. These 55 trials included 12 CHIs and 4,114 participants. The cluster analysis results suggested that Compound kushen injection therapy is the optimal CHI treatment for patients with esophageal cancer in terms of improving the clinical effectiveness rate and performance status. Huachansu and Kangai injection are superior in improving 1-year and 2-year survival rates. Lentinan injection may be considered a favorable choice for reliving ADRs, and Compound kushen injection may provide treatment benefits by reducing both gastrointestinal reaction and radiation esophagitis.

Conclusions: The current clinical evidence indicated that Compound kushen injection combined with radiotherapy is the most preferable and beneficial option for patients with esophageal cancer in terms of efficacy and safety. However, the results of our study should be interpreted with caution given the limitations of the sample size and the methodological quality of the included trials.

The current optimal multimodality treatments for oesophageal squamous-cell carcinoma: A systematic review and meta-analysis

BACKGROUND

Multimodality treatments including definitive chemoradiotherapy (dCRT) and neoadjuvant chemoradiotherapy (nCRT) or chemotherapy (nCT) followed by surgery (S) are frequently used to improve prognosis in locally advanced oesophageal squamous-cell carcinoma (LAESCC), while the optimal multimodality regimen has yet to be defined; therefore, this systematic review and meta-analysis aimed to find out the current best multimodality regimen for LAESCC.

METHODS

We conducted a systematic search of PubMed, Embase, Ovid and Cochrane Library databases for studies comparing nCRT + S with nCT + S or dCRT. The primary outcome was overall survival. The secondary outcomes were the rates of R0 resection, pathologic complete response (pCR), tumor-free lymph nodes (pN0) and postoperative recurrence.

RESULTS

Five studies comparing nCRT + S with nCT + S and fourteen studies comparing nCRT + S with dCRT were finally included. Meta-analysis showed that nCRT + S had higher rates of R0 resection (OR 1.84, 95% CI 1.03-3.29), pCR (OR: 2.90 95% CI 1.37-6.14) and pN0 (OR: 2.55 95% CI 1.54-4.24) with a significant survival advantage (HR 0.72; 95% CI 0.52-0.99) when compared with nCT + S in LAESCC. When nCRT + S was compared with dCRT, nCRT + S yielded a significant survival benefit (HR 0.65; 95% CI 0.56-0.76) and had a significantly lower rate of local recurrence (OR: 0.35 95% CI 0.22-0.57).

CONCLUSION

Current evidence suggests that CRT + S may be the optimal potential curative treatment mode for patients with LAESCC as long as they are suitable for this multimodality regimen.

Neoadjuvant chemoradiotherapy or chemotherapy? A comprehensive systematic review and meta-analysis of the options for neoadjuvant therapy for treating oesophageal cancer

Neoadjuvant therapy followed by surgery is a standard treatment for locally advanced oesophageal cancer. However, the roles of neoadjuvant chemoradiotherapy and chemotherapy in treating oesophageal cancer remain controversial. In this comprehensive meta-analysis, we examine the efficacy of adding radiotherapy to neoadjuvant chemotherapy for treating oesophageal cancer as reported in qualified randomized controlled trials (RCTs). We conducted a systematic literature search using PubMed, Embase, Cochrane Library databases, Google Scholar and the American Society of Clinical Oncology database to identify relevant studies up to 31 March 2016. Data including the pathological complete response rate, R0 resection rate and 3-year survival rate were extracted and analysed. Five qualified RCTs were included with a total of 709 patients. Meta-analysis showed that neoadjuvant chemoradiotherapy significantly increases the rates of pathological complete response and R0 resection in patients with oesophageal adenocarcinoma or squamous cell carcinoma (SCC). However, we found a significantly increased 3-year survival rate only in oesophageal SCC patients treated with neoadjuvant chemoradiotherapy compared with neoadjuvant chemotherapy (56.8 and 42.8%, respectively); relative risk (RR): 1.31 [95% confidence interval (CI) 1.10-1.58, P = 0.003]. In oesophageal adenocarcinoma patients, no significant survival benefit of neoadjuvant chemoradiotherapy was found compared with neoadjuvant chemotherapy alone (46.3 and 41.0%, respectively; RR: 1.13, 95% CI 0.88-1.45, P = 0.34). Our meta-analysis adds to the evidence showing that neoadjuvant chemoradiotherapy should be the standard preoperative treatment strategy for locally advanced oesophageal SCC. For oesophageal adenocarcinoma, neoadjuvant chemotherapy alone may be the best preoperative treatment strategy to avoid the risk of adverse effects of radiotherapy.

Comprehensive screening of genes resistant to an anticancer drug in esophageal squamous cell carcinoma

Drug resistance to chemotherapy is a major issue in esophageal cancer management. Drug resistance may be mediated by genetic changes in the tumor; therefore, the identification of gene mutations may lead to better therapeutic outcomes. We used a novel method involving transposons to screen and identify drug-resistant genes. Transposons are DNA sequences that move from one location on the gene to another. A modified piggyBac transposon was designed as an insertion mutagen, and a cytomegalovirus (CMV) promoter sequence was added to induce strong transcription. When the transposon is inserted to the upstream of a certain gene, the gene will be overexpressed while when intserted down or intragenically, it will be downregulated. After establishing a transposon-tagged cell library, we treated cell lines derived from esophageal squamous cell carcinomas (ESCC) [Tohoku esophagus (TE)] with cisplatin (CDDP). We performed splinkerette PCR and TOPO cloning on the resistant colonies. Bacterial colonies were sequenced, and next-generation sequencing was used to identify the overexpressed/downregulated sequences as candidate genes for CDDP resistance. We established 4 cell lines of transposon-tagged cells, TE4, 5, 9 and 15. We treated the two relatively viable cell lines, TE4 and TE15, with CDDP. We identified 37 candidate genes from 8 resistant colonies. Eight genes were overexpressed whilst 29 were downregulated. Among these genes was Janus kinase 2 (JAK2) that is implicated in the progression of myeloproliferative neoplasms. We identified 37 candidate genes responsible for CDDP resistance in the two cell lines derived from ESCC cells. The method is inexpensive, relatively simple, and capable of introducing activating and de-activating mutations in the genome, allowing for drug-resistant genes to be identified.