High dose-rate endoluminal brachytherapy for primary and recurrent esophageal cancer: Experience from a large single-center cohort

Meta analysis of the second course of radiotherapy for recurrent esophageal cancer1

BACKGROUND

How to improve efficacy and reduce side effects in treating recurrent esophageal cancer by applying the second course of radiotherapy alone and its combination with chemotherapy has been attracting broad research interest.

OBJECTIVE

This review paper aims to systematically evaluate efficacy and side effects of applying the second course of anterograde radiotherapy alone and its combination with chemotherapy in treating recurrent esophageal cancer.

METHODS

First, the relevant research papers are retrieved from PubMed, CNKI and Wanfang databases. Next, Redman 5.3 software is used to calculate the relative risk and 95% confidence interval to evaluate the efficacy and adverse reactions of applying the single-stage radiotherapy with and without combining single/multi dose chemotherapy to treat recurrent esophageal cancer. Then, a meta data analysis is applied to examine the effectiveness and side effects of radiation alone and re-course radiotherapy plus chemotherapy in treating esophageal cancer recurrence after the first radiotherapy.

RESULTS

Fifteen papers are retrieved, which included 956 patients. Among them, 476 patients received radiotherapy combined with single drug/multi drug chemotherapy (observation) and others received only radiotherapy (control). Data analysis results show that the incidence of radiation induced lung injury and bone marrow suppression is high in the observation group. Subgroup analysis also shows the higher effective rate or one-year overall survival rate of patients treated with the second course radiotherapy combined with single drug chemotherapy.

CONCLUSION

The meta-analysis result demonstrates that combining the second course of radiotherapy with single-drug chemotherapy has advantages in treating recurrent esophageal cancer with the manageable side effects. However, due to insufficient data, it is not possible to conduct the further subgroup analysis comparing the side effects of restorative radiation with the combined chemotherapy using between a single drug and multiple drugs.

Dose reduction in HDR brachytherapy of esophageal cancer using gold and gold alloy plaques: a Monte Carlo study

In this work, the use of gold and gold alloy plaques is proposed for the first time, to reduce the dose to healthy organs in brachytherapy with Ir-192 sources. For dose simulations in tumour and healthy tissue, the MCNPX Monte Carlo code was used. The radiation source implemented in those simulations was benchmarked with well-known TG-43 criteria of dose rate constant, air-kerma strength, radial dose function, and 2D anisotropy function. For various arrangements of iridium sources and plaques of gold and gold alloy of various thicknesses, the dose distributions in an esophagus tumour and in surrounding healthy organs were simulated. The results showed that while the dose to the tumour is not much affected by the presence of gold plaques with a thickness of 3.5 mm in an optimized ¹⁹²Ir sources' configuration, a relative reduction in average organ dose of 64%, 65%, 73%, 67%, and 35% was observed, for esophagus, thyroid, heart, stomach, and liver, respectively. Moreover, it was found that a gold plaque leads to smaller doses to healthy organs than a gold alloy plaque. It is concluded that gold plaques can be used to improve the treatment of esophageal cancer by HDR brachytherapy and to protect surrounding non-target organs.

External beam radiotherapy with or without californium-252 neutron brachytherapy for treatment of recurrence after definitive chemoradiotherapy

We aimed to evaluate the application of external beam radiotherapy (EBRT) combined with californium-252 (²⁵²Cf) neutron intraluminal brachytherapy (NBT) in patients with local recurrent esophageal cancer after definitive chemoradiotherapy (CRT). Sixty-two patients with local recurrent esophageal squamous cell carcinoma after definitive CRT were retrospectively analyzed; 31 patients underwent NBT+EBRT, and 31 received EBRT alone. The response rate; 1-, 2-, and 3-year overall survival rates; and adverse event occurrence rates were compared between these two patient groups. The response rate was 83.87% (26/31) in the NBT+EBRT group and 67.74% (21/31) in the EBRT group (p < 0.001). The 1-, 2-, and 3-year overall survival rates were 80.6%, 32.3%, and 6.5%, respectively, in the EBRT group, with a median survival time of 18 months. The 1-, 2-, and 3-year overall survival rates were 83.8%, 41.9%, and 6.9%, respectively, in the NBT+EBRT group, with a median survival time of 19 months. The differences between the groups were not significant (p = 0.352). Regarding acute toxicity, no incidences of fistula or massive bleeding were observed during the treatment period. The incidences of severe and late complications were not significantly different between the two groups (p = 0.080). However, the causes of death for all patients differed between the groups. Our data indicate that ²⁵²Cf-NBT+EBRT produces favorable local control for patients with local recurrent esophageal cancer after CRT, with tolerable side effects.

Esophageal brachytherapy: Institut Gustave Roussy's experience

PURPOSE

Esophageal cancer is characterized by its propension to local evolution, which conditions prognosis and quality of life. Brachytherapy may be a therapeutic option for all stages of esophageal cancer.

METHODS AND MATERIALS

This retrospective unicentric study included all consecutive patients treated for an esophageal high-dose-rate brachytherapy in our institution from 1992 to 2018.

RESULTS

Ninety patients were included. They were treated in four distinct indications: exclusive (7 patients), boost after external beam radiotherapy (41), reirradiation (36), or palliative aim (6). Most frequently prescribed schemes were 3 × 5 Gy (boost) or 6 × 5 Gy (exclusive treatment and reirradiation) at applicator's surface or at 5 mm. At the end of follow-up, 50% of patients had presented with local recurrence. Seventeen percent of patients had a metastatic relapse. Median overall survival was 15 months in the whole cohort: 22 months in the boost setting, 25 months for exclusive brachytherapy, 15 months for reirradiation, and only 2 months for palliative treatment. Tumor length at brachytherapy, brachytherapy dose, and interfraction response were significantly associated to overall survival. 40% of patients presented with grade 2+ toxicity, mostly esophagitis, including three toxic deaths.

CONCLUSIONS

Although local control outcomes are still poor, one must remember that patients are unfit for any curative therapeutic option and that palliative chemotherapy offers mediocre results. The most promising setting probably is reirradiation because brachytherapy offers a remarkable dose gradient allowing best organ at risk sparing, with an encouraging rate of long survivors (19% at 2 years). Esophageal brachytherapy deserves to be further investigated because some patients, even unfit, may benefit from it, with acceptable toxicity.

[Normal tissue: radiosensitivity, toxicity, consequences for planning]

Along with chemotherapy, surgery and immunotherapy, radiotherapy is a mainstay of cancer treatment. Considering the improving survival rates for various malignancies during the past decades, the importance of radiation-induced late normal tissue response is increasing. Quality of life is becoming an important issue in modern cancer treatment and is correlated with acute and late normal tissue response after radiotherapy. A profound understanding of radiation-induced normal tissue response is necessary to sufficiently diagnose and treat radiation-induced side effects and thereby increase the patients' quality of life. Here, the various normal tissue responses in consideration of the radiation biology are specified and prospective options to attenuate radiation-induced side effects are discussed.

Differential response of esophageal cancer cells to particle irradiation

Background

Radiation therapy is a mainstay in the treatment of esophageal cancer (EC) patients, and photon radiotherapy has proved beneficial both in the neoadjuvant and the definitive setting. However, regarding the still poor prognosis of many EC patients, particle radiation employing a higher biological effectiveness may help to further improve patient outcomes. However, the influence of clinically available particle radiation on EC cells remains largely unknown.

Methods

Patient-derived esophageal adenocarcinoma and squamous cell cancer lines were treated with photon and particle irradiation using clinically available proton (¹H), carbon (¹²C) or oxygen (¹⁶O) beams at the Heidelberg Ion Therapy Center. Histology-dependent clonogenic survival was calculated for increasing physical radiation doses, and resulting relative biological effectiveness (RBE) was calculated for each radiation modality. Cell cycle effects caused by photon and particle radiation were assessed, and radiation-induced apoptosis was measured in adenocarcinoma and squamous cell EC samples by activated caspase-3 and sub-G1 populations. Repair kinetics of DNA double strand breaks induced by photon and particle radiation were investigated.

Results

While both adenocarcinoma EC cell lines demonstrated increasing sensitivities for ¹H, ¹²C and ¹⁶O radiation, the two squamous cell carcinoma lines exhibited a more heterogeneous response to photon and particle treatment; average RBE values were calculated as 1.15 for ¹H, 2.3 for ¹²C and 2.5 for ¹⁶O irradiation. After particle irradiation, squamous cell EC samples reacted with an increased and prolonged block in G2 phase of the cell cycle compared to adenocarcinoma cells. Particle radiation resulted in an incomplete repair of radiation-induced DNA double strand breaks in both adenocarcinoma and squamous cell carcinoma samples, with the levels of initial strand break induction correlating well with the individual cellular survival after photon and particle radiation. Similarly, EC samples demonstrated heterogeneous levels of radiation-induced apoptosis that also corresponded to the observed cellular survival of individual cell lines.

Conclusions

Esophageal cancer cells exhibit differential responses to irradiation with photons and ¹H, ¹²C and ¹⁶O particles that were independent of tumor histology. Therefore, yet unknown molecular markers beyond histology may help to establish which esophageal cancer patients benefit from the biological effects of particle treatment.

Electronic supplementary material

The online version of this article (10.1186/s13014-019-1326-9) contains supplementary material, which is available to authorized users.

Neoadjuvant chemoradiation for esophageal cancer : Surgery improves locoregional control while response based on FDG-PET/CT predicts survival

INTRODUCTION

To retrospectively analyze the outcome of patients with esophageal cancer treated with neoadjuvant chemoradiation.

METHODS

A total of 41 patients received neoadjuvant intent chemoradiation for esophageal cancer. Most patients had a locally advanced disease (T3/4: 82%, N+: 83%, M0: 100%) and squamous cell carcinoma (83%). All patients received concurrent chemotherapy with cisplatin/5-fluorouracil or mitomycin/5-fluorouracil. Median radiation dose was 50.4 Gy in the 25 patients who proceeded to surgery and 57.4 Gy in 16 patients who did not undergo surgery. FDG-PET/CT was used for treatment planning in 24 patients. A second FDG-PET/CT was available for response evaluation in 18 patients.

RESULTS

Median follow-up was 16 months in all patients and 30 months in survivors. Radiotherapy was completed without interruptions >3 days in 90% of patients, and chemotherapy was carried out to >80% in 85% of patients. The 2‑year locoregional control rate was 60%, distant control rate 54% and overall survival rate 50%. Hematological toxicity grade 3/4 was observed in 34%/10% of patients and non-hematological toxicity grade 3/4 in 46%/2% of patients. Perioperative 30-day mortality was 4%. Subgroup analyses revealed that surgery significantly improved locoregional control (74% vs. 39%, p = 0.034), but not the 2‑year survival rate (54% vs. 43%, p = 0.246). In contrast, response based on FDG-PET/CT prior and after chemoradiation significantly predicted improved overall survival (2-year overall survival 61% vs. 40%, p = 0.048).

CONCLUSION

Outcomes of our cohort were comparable to other series using similar treatments. Surgery significantly improved locoregional control but not survival. Response based on FDG-PET/CT predicted survival and might be used for treatment stratification.