Treatment of esophageal cancer with radiation therapy -a pan-Chinese survey of radiation oncologists

Neoadjuvant Radiotherapy Facility Type Affects Anastomotic Complications After Esophagectomy

BACKGROUND

Esophagectomy is a complex oncologic surgery that results in lower perioperative morbidity and mortality when performed in high-volume hospitals by experienced surgeons; however, limited data exists evaluating the importance of neoadjuvant radiotherapy delivery at high- versus low-volume centers. We sought to compare postoperative toxicity among patients treated with preoperative radiotherapy delivered at an academic medical center (AMC) versus community medical centers (CMC).

METHODS

Consecutive patients undergoing esophagectomy for locally advanced esophageal or gastroesophageal junction (GEJ) cancer at an academic medical center between 2008 and 2018 were reviewed. Associations between patient factors and treatment-related toxicities were calculated in univariate (UVA) and multivariable analyses (MVA).

RESULTS

One hundred forty-seven consecutive patients were identified: 89 CMC and 58 AMC. Median follow-up was 30 months (0.33-124 months). Most patients were male (86%) with adenocarcinoma (90%) located in the distal esophagus or GEJ (95%). Median radiation dose was 50.4 Gy between groups. Radiotherapy at CMCs resulted in higher rates of re-operation after esophagectomy (18% vs 7%, p = 0.055) and increased rates of anastomotic leak (38% vs 17%, p < 0.01). On MVA, radiation at a CMC remained predictive of anastomotic leak (OR 6.13, p < 0.01).

CONCLUSION

Esophageal cancer patients receiving preoperative radiotherapy had higher rates of anastomotic leaks when radiotherapy was completed at a community medical center versus academic medical center. Explanations for these differences are uncertain but further exploratory analyses regarding dosimetry and radiation field size are warranted.

Mechanism and clinical value of exosomes and exosomal contents in regulating solid tumor radiosensitivity

Radiotherapy is among the routine treatment options for malignant tumors. And it damages DNA and other cellular organelles in target cells by using ionizing radiation produced by various rays, killing the cells. In recent years, multiple studies have demonstrated that exosomes are mechanistically involved in regulating tumor formation, development, invasion and metastasis, and immune evasion. The latest research shows that radiation can affect the abundance and composition of exosomes as well as cell-to-cell communication. In the environment, exosome-carried miRNAs, circRNA, mRNA, and proteins are differentially expressed in cancer cells, while these molecules play a role in numerous biological processes, including the regulation of oncogene expression, mediation of signaling pathways in cancer cells, remodeling of tumor-related fibroblasts, regulation of cell radiosensitivity, and so forth. Therefore, elucidation of the mechanism underlying the role of exosomes in radiotherapy of malignant tumors is crucial for improving the efficacy of radiotherapy. This review will summarize the research advances in radiosensitivity of malignant tumors related to exosomes.

Comparison of the effect of postoperative radiotherapy with surgery alone for esophagus squamous cell carcinoma patients: A meta-analysis

BACKGROUND

This meta-analysis was conducted to evaluate the effect of postoperative radiotherapy for patients having esophagus squamous cell carcinoma after radical surgery.

METHODS

A comprehensive research was performed in Pubmed, Embase and Cochrane Library electronic databases from inception until December 10, 2017. We collected all published full articles about comparison of surgery plus postoperative radiotherapy with surgery alone.

RESULTS

Four randomized-controlled trials (RCTs) with 1050 participants and 8 non-randomized-controlled trials with 3248 participants were included and evaluated separately. The risk ratio rate and its 95% confidence interval (CI) were calculated. Both RCTs and non-randomized-controlled trials (NRCTs) groups showed a significant increase in 3-year overall survival (OS) rate (RRRCT = 0.89, 95% CI: 0.80-0.99; RRNRCT = 0.82, 95% CI: 0.76-0.88) and decrease locoregional recurrence rate (RRRCT = 0.53, 95% CI: 0.43-0.66; RRNRCT = 0.47, 95% CI: 0.32-0.69) after postoperative radiotherapy compared with surgery alone. The 5-year OS rate in the group of NRCTs was markedly enhanced (RR = 0.87, 95% CI: 0.82-0.92), while that of the RCTs group was not enhanced in a significant way (RR = 0.84, 95% CI: 0.70-1.02). Subgroup analysis based on pathological lymph node status revealed that postoperative radiotherapy could improve OS regardless of pathological lymph node status (pathological lymph node positive patients: RR5-year os-RCT = 0.81, 95% CI: 0.70-0.93; RR5-year os-NRCT = 0.87, 95% CI: 0.80-0.94; Pathological lymph node negative patients: RR3-year os-RCT = 0.76, 95% CI: 0.59-0.96; RR3-year os-NRCT = 0.52, 95% CI: 0.30-0.89). No effect on distant recurrence rate was detected. Adverse effects induced by postoperative radiotherapy were comparatively modest and tolerable.

CONCLUSION

Polled results yielded that postoperative radiotherapy was promising in improving OS and reducing the locoregional recurrence rate. More large-scale up-to-date RCTs are needed to further validate the use of postoperative radiotherapy in modern practice.