Clinical outcomes of mild hyperthermia for locally advanced rectal cancer treated with preoperative radiochemotherapy

Neoadjuvant chemoradiotherapy in combination with deep regional hyperthermia followed by surgery for rectal cancer: a systematic review and meta-analysis

BACKGROUND AND PURPOSE

Combining chemoradiotherapy (CRT) with deep regional hyperthermia (HT) shows promise for enhancing clinical outcomes in selected rectal cancer patients. This study aimed to integrate the evidence and evaluate the efficacy of this combined treatment approach.

MATERIALS AND METHODS

A systematic search of the PubMed, Scopus, and Mendeley databases was performed. This review was conducted according to the PRISMA guidelines. The quality of studies was evaluated using the Newcastle-Ottawa scale (NOS). Random-effects meta-analyses (DerSimonian and Laird) were performed. The primary outcome was pathological complete response (pCR), and secondary endpoints were overall survival (OS), disease-free survival (DFS), local recurrence-free survival (LRFS), and toxicity.

RESULTS

In total, 12 studies were included, mostly of moderate quality. Patients with locally advanced rectal cancer (LARC; n = 760) and locally recurrent rectal cancer (LRRC; n = 22) were eligible. The pooled pCR rate was 19% (95% confidence interval [CI]: 16-22%) among all 782 patients and 19% (95%CI:16-23%) among 760 LARC patients. Due to significant study heterogeneity, survival outcomes were pooled by excluding LRRC patients. The pooled 5‑year OS rate among 433 LARC patients was 87% (95%CI: 83-90%). The pooled 5‑year DFS and LRFS in LARC patients were 75% (95%CI: 70-80%) and 95% (95%CI: 92-97%), respectively. There was a lack of consistent reporting of HT treatment parameters and toxicity symptoms among the studies.

CONCLUSION

The collective clinical evidence showed that neoadjuvant CRT combined with HT in rectal cancer patients is feasible, with a 19% pCR rate and excellent survival outcomes in long term follow-up.

Mild hyperthermia with magnetic resonance- guided high intensity focused ultrasound combined with salvage chemoradiation for recurrent rectal cancer

INTRODUCTION

Pelvic recurrences from rectal cancer present a challenging clinical scenario. Hyperthermia represents an innovative treatment option in combination with concurrent chemoradiation to enhance therapeutic effect. We provide the initial results of a prospective single center feasibility study (NCT02528175) for patients undergoing rectal cancer retreatment using concurrent chemoradiation and mild hyperthermia with MR-guided high intensity focused ultrasound (MR-HIFU).

METHODS

All patients were deemed ineligible for salvage surgery and were evaluated in a multidisciplinary fashion with a surgical oncologist, radiation oncologist and medical oncologist. Radiation was delivered to a dose of 30.6 Gy in 1.8 Gy per fraction with concurrent capecitabine. MR-HIFU was delivered on days 1, 8 and 15 of concurrent chemoradiation. Our primary objective was feasibility and toxicity.

RESULTS

Six patients (total 11 screened) were treated with concurrent chemoradiation and mild hyperthermia with MR-HIFU. Tumor size varied between 3.1-16.6 cm. Patients spent an average of 228 min in the MRI suite and sonication with the external transducer lasted an average of 35 min. There were no complications on the day of the MR-HIFU procedure and all acute toxicities (no grade >/=3 toxicities) resolved after completion of treatment. There were no late grade >/=3 toxicities.

CONCLUSION

Mild hyperthermia with MR-HIFU, in combination with concurrent chemoradiation for appropriately selected patients, is safe for localized pelvic recurrences from rectal cancer. The potential for MR-HIFU to be applied in the recurrent setting in rectal cancer treatment requires further technical development and prospective evaluation.

Deep regional hyperthermia combined with modern concurrent chemoradiotherapy increases T-downstaging rate in locally advanced rectal cancer

BACKGROUND

Deep regional hyperthermia might have an additional effect on radiotherapy in treating locally advanced rectal cancer (LARC). This study aimed to investigate the role of hyperthermia combined with modern preoperative concurrent chemoradiotherapy (CRT) for LARC.

METHODS AND MATERIALS

From 2012 to 2018, 152 consecutive patients with LARC treated with neoadjuvant chemoradiation were enrolled and analyzed retrospectively. Pelvic radiotherapy (45-50 Gy) was delivered as volumetric modulated arc therapy (VMAT), concurrently with capecitabine chemotherapy. Fifty patients received hyperthermia combined with CRT (HCRT group) twice a week. Treatment response and outcomes were compared between the two groups. Furthermore, the relationships between peripheral blood neutrophil-to-lymphocyte ratio (NLR), platelet-to-lymphocyte ratio (PLR) and lymphocyte-to-monocyte ratio (LMR) in response to hyperthermia were analyzed.

RESULTS

Patients treated with hyperthermia had a significantly higher T-downstaging rate than those without hyperthermia (82.0 vs. 62.7%; p = .016). Hyperthermia was an independent favorable predictor of T-downstaging (odds ratio [OR] = 2.473; 95% confidence interval [CI] 1.050-5.826; p = .038). In the HCRT group, a pre-therapeutic elevated NLR (≥3) was associated with a higher T-downstaging rate (100.0 vs. 73.5%, p = .043). However, NLR was not associated with the T-downstaging rate in the CRT group. Five-year rates of locoregional recurrence-free survival (96.8 vs. 94.7%, p = .959), disease-free survival (DFS; 61.4 vs. 79.3%, p = .242), and overall survival (OS; 92.7 vs. 89.8%, p = .831) were not statistically different between the CRT and HCRT groups.

CONCLUSIONS

Hyperthermia can improve preoperative treatment response in LARC. Pretreatment NLR may be a predictive factor for hyperthermia.

Long-Term Feasibility of 13.56 MHz Modulated Electro-Hyperthermia-Based Preoperative Thermoradiochemotherapy in Locally Advanced Rectal Cancer

Simple Summary

We demonstrated that a 13.56 MHz modulated electro-hyperthermia (mEHT) boost is feasible in neoadjuvant treatment for rectal cancer. Herein, we attempted to present the long-term results for this phase 2 trial. Although there are many reports on the usefulness of thermoradiochemotherapy for loco-regional control, so far, only a few cases of survival benefit exist. Thus, this study assessed whether this limitation of hyperthermia could be overcome through the mEHT method featuring an applied energy variable. Following a median follow-up of 58 months for 60 patients, mEHT boost showed comparable results with conventional hyperthermia; potential therapeutic effects were also observed. Moreover, mEHT could be considered a useful tool in combination treatment with radiotherapy owing to its low thermotoxicity and improved treatment compliance.

Abstract

We evaluated the effect of 13.56 MHz modulated electro-hyperthermia (mEHT) boost in neoadjuvant treatment for cT3-4- or cN-positive rectal cancer. Sixty patients who completed the mEHT feasibility trial (ClinicalTrials.gov Identifier: NCT02546596) were analyzed. Whole pelvis radiotherapy of 40 Gy, mEHT boost twice a week during radiotherapy, and surgical resection 6–8 weeks following radiotherapy were performed. The median age was 59. The median follow-up period was 58 (6–85) months. Total/near total tumor regression was observed in 20 patients (33.3%), including nine cases of complete response. T- and N-downstaging was identified in 40 (66.6%) and 53 (88.3%) patients, respectively. The 5-year overall and disease-free survival were 94.0% and 77.1%, respectively. mEHT energy of ≥3800 kJ potentially increased the overall survival (p = 0.039). The ypN-stage and perineural invasion were possible significant factors in disease-free (p = 0.003 and p = 0.005, respectively) and distant metastasis-free (p = 0.011 and p = 0.034, respectively) survival. Tumor regression, resection margin status, and other molecular genetic factors showed no correlation with survival. Although a limited analysis of a small number of patients, mEHT was feasible considering long-term survival. A relatively low dose irradiation (40 Gy) plus mEHT setting could ensure comparable clinical outcomes with possible mEHT-related prognostic features.

Recent advances in in situ oxygen-generating and oxygen-replenishing strategies for hypoxic-enhanced photodynamic therapy

Cancer is a leading cause of death worldwide, accounting for an estimated 10 million deaths by 2020. Over the decades, various strategies for tumor therapy have been developed and evaluated. Photodynamic therapy (PDT) has attracted increasing attention due to its unique characteristics, including low systemic toxicity and minimally invasive nature. Despite the excellent clinical promise of PDT, hypoxia is still the Achilles' heel associated with its oxygen-dependent nature related to increased tumor proliferation, angiogenesis, and distant metastases. Moreover, PDT-mediated oxygen consumption further exacerbates the hypoxia condition, which will eventually lead to the poor effect of drug treatment and resistance and irreversible tumor metastasis, even limiting its effective application in the treatment of hypoxic tumors. Hypoxia, with increased oxygen consumption, may occur in acute and chronic hypoxia conditions in developing tumors. Tumor cells farther away from the capillaries have much lower oxygen levels than cells in adjacent areas. However, it is difficult to change the tumor's deep hypoxia state through different ways to reduce the tumor tissue's oxygen consumption. Therefore, it will become more difficult to cure malignant tumors completely. In recent years, numerous investigations have focused on improving PDT therapy's efficacy by providing molecular oxygen directly or indirectly to tumor tissues. In this review, different molecular oxygen supplementation methods are summarized to alleviate tumor hypoxia from the innovative perspective of using supplemental oxygen. Besides, the existing problems, future prospects and potential challenges of this strategy are also discussed.

Development of an ultrasonic nonlinear frequency compounding method with applications in tissue thermometry

Frequency compounding is an ultrasound imaging technique used to improve signal-to-noise ratio (SNR). In this work, a nonlinear frequency compounding (NLFC) method was introduced, and its application in noninvasive tissue thermometry investigated. The NLFC method was used to produce two-dimensional maps of the temperature sensitive change in backscattered energy of acoustic harmonics (hCBE), during heating of ex vivo porcine tissue with a low intensity focused ultrasound transducer. A hCBE-to-temperature calibration was performed, and temperature maps produced and compared with a theoretical COMSOL based model. Last, a comparative study of the NLFC and previously used nonlinear single frequency (NLSF) methods was completed to quantify the improvement in SNR of the produced hCBE maps. When using the NLFC method, a SNR of 6.06 ± 1.28 was found. SNR values of 3.70 ± 0.53 and 4.38 ± 0.84 were found while using central frequencies of 4.31 and 5.43 MHz, respectively, with the NLSF method. This translates to an improvement of (64.13 ± 4.16)% over the 4.31 MHz NLSF, and (38.72 ± 2.97)% over the 5.43 MHz NLSF methods overall. It was concluded that the NLFC method can produce hCBE and temperature maps with superior image SNR over the NLSF method.

Deep regional hyperthermia with preoperative radiochemotherapy in locally advanced rectal cancer, a prospective phase II trial

PURPOSE

The goal of the present study was to investigate the effect of deep regional hyperthermia on early and long-term oncological outcomes in the context of preoperative radiochemotherapy in rectal cancer.

METHODS

In this prospective phase II trial, patients with locally advanced rectal cancer were treated with 5-fluorouracil based preoperative radiochemotherapy with 50.4 Gy in 28 fractions. Deep regional hyperthermia was scheduled twice weekly. Pathological tumor regression was scored according to the Dworak regression system. The primary endpoint was pathological complete response (pCR). Further endpoints were local control (LC), distant control (DC), disease-free survival (DFS) and overall survival (OS). Hyperthermia was defined as feasible if 70% of patients received at least eight treatments. Quality of life was assessed at follow-up by the EORTC-QLQ-C30 and QLQ-CR29 questionnaires. Time to event data was analyzed according to Kaplan-Meier based on first-events. The study was registered on clinicaltrials.gov (NCT02353858).

RESULTS

From 2012 until 2017, 78 patients were recruited. Median follow-up was 54 months. Based on magnetic resonance imaging, the mesorectal fascia was involved or threatened in 60% of the patients. Compliance with radiotherapy was 99%, 91% received both cycles of chemotherapy and 77% had eight or more hyperthermia treatments. Median time from the end of radiotherapy to surgery was 6.7 weeks. A pathological complete response was reported in 14% of the patients, 50% had either Dworak 4 (complete regression) or Dworak 3 regression (scattered tumor cells only). Three year estimates for OS, DFS, LC and DC were 94%, 81%, 96% and 87%. Patients with higher hyperthermia related cumulative temperatures showed stronger tumor regression. Global health status based on EORTC-QLQ-C30 was comparable with data from the general population.

CONCLUSION

Deep regional hyperthermia was feasible, did not compromise standard treatments and resulted in promising long-term oncological outcomes and QoL.

Selecting patients for hyperthermia combined with preoperative chemoradiotherapy for locally advanced rectal cancer

BACKGROUND

This study investigated the role of hyperthermia combined with preoperative concurrent chemoradiotherapy (CCRT) for locally advanced rectal cancer (LARC) according to hypoxic marker expression.

METHODS

One hundred and nine LARC patients with tissue blocks available for immunohistochemical assessment of carbonic anhydrase 9 (CA9) expression were reviewed. CA9 expression was considered positive when the staining percentage of tumor cells was >25% (n = 31). Pelvic radiotherapy with a total dose of 39.6-45 Gy was delivered concurrently with fluorouracil-based chemotherapy. Hyperthermia was administered to 52 patients twice a week during CCRT. Treatment response and outcomes were compared between hyperthermochemoradiotherapy (HCRT) and CCRT groups.

RESULTS

In patients with positive CA9 expression, the rates of downstaging (p = 0.060) and pathologic complete response (p = 0.064) tended to be higher in the HCRT group than in the CCRT group. Distant metastasis-free survival (p = 0.029) and cancer-specific survival (p = 0.020) were significantly worse in tumors with both positive CA9 expression and poor tumor response. Negative CA9 expression, presence of major tumor response, and the use of hyperthermia were significant favorable prognostic factors for cancer-specific survival after the first recurrence in multivariate analysis.

CONCLUSIONS

Hyperthermia might selectively enhance the preoperative treatment response in LARC with positive CA9 expression and offset the negative effect of hypoxia on prognosis. Pretreatment evaluation of hypoxia could aid in the selection of patients who might benefit from hyperthermia.

Integrating Hyperthermia into Modern Radiation Oncology: What Evidence Is Necessary?

Hyperthermia (HT) is one of the hot topics that have been discussed over decades. However, it never made its way into primetime. The basic biological rationale of heat to enhance the effect of radiation, chemotherapeutic agents, and immunotherapy is evident. Preclinical work has confirmed this effect. HT may trigger changes in perfusion and oxygenation as well as inhibition of DNA repair mechanisms. Moreover, there is evidence for immune stimulation and the induction of systemic immune responses. Despite the increasing number of solid clinical studies, only few centers have included this adjuvant treatment into their repertoire. Over the years, abundant prospective and randomized clinical data have emerged demonstrating a clear benefit of combined HT and radiotherapy for multiple entities such as superficial breast cancer recurrences, cervix carcinoma, or cancers of the head and neck. Regarding less investigated indications, the existing data are promising and more clinical trials are currently recruiting patients. How do we proceed from here? Preclinical evidence is present. Multiple indications benefit from additional HT in the clinical setting. This article summarizes the present evidence and develops ideas for future research.

Chemoradiation combined with regional hyperthermia for advanced oesophageal cancer: a systematic review and meta-analysis

WHAT IS KNOWN AND OBJECTIVE

Hyperthermia is an effective treatment modality that augments the anticancer effects of radiotherapy and chemotherapy. Hyperthermia-chemo-radiotherapy (HCRT) is a combination therapy that can strengthen anticancer effects through a synergistic interaction between heat, chemotherapy and radiation. Here, we carried out a systematic review and meta-analysis to evaluate the clinical efficacy and safety of chemoradiation combined with regional hyperthermia (HCRT) for oesophageal carcinoma.

METHODS

We conducted computer searches of foreign databases, including Cochrane Library, PubMed, EMBASE, Web of Science and Chinese databases, including CBM, CNKI and WanFang; we also retrieved other sources as supplement. All relevant randomized controlled trials (RCTs) were collected to compare HCRT and other therapies, including chemotherapy combined with radiotherapy (CRT) and radiotherapy alone (RT). After literature screening, data extraction and quality evaluation performed by appropriate criteria, the meta-analyses were conducted using RevMan 5.1 software (The Nordic Cochrane Centre, The Cochrane Collaboration, Copenhagen, Denmark).

RESULTS AND DISCUSSION

Nineteen RCTs were included, comprising 1519 patients. Meta-analysis showed that the 1-, 3-, 5- and 7-year survival, complete response and total effective rates of the HCRT group were higher than those of the CRT group; the rates of gastrointestinal reaction, leucocytopenia and radiation oesophagitis in the HCRT group were lower than those of the CRT group, indicating significant differences (P < 0·05). The 1-, 2-, 3- and 5-year survival, complete response and total effective rates of the HCRT group were higher than those of the RT group, the recurrence and distant metastasis rates of the HCRT group were lower than those of the RT group, and there were significant differences in all of the indicators (P < 0·05).

WHAT IS NEW AND CONCLUSIONS

This is the first systematic review and meta-analysis to evaluate HCRT for oesophageal carcinoma. Compared with CRT or RT, HCRT can improve long-term and short-term curative effects; it is also safe and feasible. Additional high-quality and large sample size RCTs will be necessary to further demonstrate the long-term survival benefits and comprehensive safety profile of HCRT.

Long-term local control and survival after preoperative radiochemotherapy in combination with deep regional hyperthermia in locally advanced rectal cancer

PURPOSE

The aim of this study was to evaluate the impact of deep regional hyperthermia on long-term local control and survival in locally advanced non-metastatic rectal cancer.

METHODS

In total 103 patients with locally advanced non-metastatic rectal cancer were treated preoperatively with either neoadjuvant radiochemotherapy alone (n = 43) or the same treatment with additional deep regional hyperthermia (n = 60). The two groups were compared with respect to local control, overall survival (OS), disease-free survival (DFS), and distant metastases-free survival (DMFS).

RESULTS

Patients receiving additional hyperthermia had excellent long-term local control with a 5-year Kaplan-Meier estimate of 98% compared with 87% in the radiochemotherapy only group (p = 0.09). Five-year rates for OS (88% versus 76%, p = 0.08), DFS (77% versus 73%, p = n.s.) and DMFS (75% versus 77%, p = n.s.) were not statistically different between the two groups.

CONCLUSION

Radiochemotherapy combined with hyperthermia results in excellent long-term local control.

Surgery combined with intraoperative hyperthermic intraperitoneal chemotherapy (IHIC) for gastric cancer: a systematic review and meta-analysis of randomised controlled trials

BACKGROUND

Adjuvant intraoperative hyperthermic intraperitoneal chemotherapy (IHIC) is a therapy which combines thermotherapy and intraperitoneal chemotherapy. It is theoretically powerful for patients with advanced gastric cancer (AGC), but is there evident advantage in clinical practice? We need evidence to guide our decision-making.

OBJECTIVES

Meta-analysis was performed to assess the effectiveness and safety of adjuvant intraoperative hyperthermic intraperitoneal chemotherapy (IHIC) for patients with resectable locally advanced gastric cancer, and to provide the reference for clinical practice and study.

METHODS

We searched the Cochrane Library, PubMed, Embase, Web of Science and Chinese databases (Chinese BioMedical Literature Database (CBM), China National Knowledge Infrastructure (CNKI) and Wanfang) electronically and also retrieved papers from other sources (tracing related references and communication with other authors). All relevant randomised controlled trials (RCTs) were collected to compare surgery combined with IHIC to surgery without IHIC for AGC. There were no language restrictions. After independent quality assessment and data extraction by two reviewers, meta-analysis was conducted by RevMan 5.1 software.

RESULTS

16 RCTs involving 1,906 patients were included. Compared with surgery alone, combination therapy (surgery plus IHIC) was associated with a significant improvement in survival rate at 1 year (hazard ratio (HR) = 2.99; 95% confidence interval (CI) = 2.21 to 4.05; p < 0.00001), 2 years (HR = 2.43; 95%CI = 1.81 to 3.26; p < 0.00001), 3 years (HR = 2.63; 95%CI = 2.17 to 3.20; p < 0.00001), 5 years (HR = 2.49; 95%CI = 1.97 to 3.14; p < 0.00001), and 9 years (HR = 2.14; 95%CI = 1.38 to 3.32; p = 0.0007). Compared with surgery alone, combination therapy was associated with a significant reduction in recurrence rate at 2 years (RR = 0.42; 95%CI = 0.29 to 0.61; p < 0.00001), 3 years (RR = 0.35; 95%CI = 0.24 to 0.51; p < 0.00001) and 5 years (RR = 0.47; 95%CI = 0.39 to 0.56; p < 0.00001). IHIC was not found to be associated with higher risks of anastomotic leakage, ileus, bowel perforation, myelosuppression, gastrointestinal reaction and hypohepatia, but it increased the incidence of abdominal pain (RR = 21.46; 95%CI = 5.24 to 87.78; p < 0.00001).

CONCLUSIONS

Compared with surgery alone, surgery combined with IHIC can improve survival rate and reduce the recurrence rate, with acceptable safety. However, safety outcomes should be further evaluated by larger samples and high quality studies. Additionally, hyperthermia for the intraperitoneal chemotherapy needs more clinical research.

Quality assurance: recommended guidelines for safe heating by capacitive-type heating technique to treat patients with metallic implants

This article is a redissemination of the previous Japanese Quality Assurance Guide guidelines. Specific absorption rate and temperature distribution were investigated with respect to various aspects including metallic implant size and shape, insertion site, insertion direction, blood flow and heating power, and simulated results were compared with adverse reactions of patients treated by radio frequency capacitive-type heating. Recommended guidelines for safe heating methods for patients with metallic implants are presented based on our findings.

Conductive thermal ablation of 4T1 murine breast carcinoma reduces severe hypoxia in surviving tumour

PURPOSE

The purpose of this study was to quantify hypoxia changes in viable tumour volumes after thermal ablation of a murine breast carcinoma.

METHODS

Murine breast 4T1 tumours were grown in the rear leg of BALB/c mice to an average diameter of 10-12 mm. Tumours were treated with conductive interstitial thermal therapy (CITT) at a peak temperature of 80-90°C for 10 min. The animals were euthanised 72 h later, and the tumours were removed for immunohistochemical staining with pimonidazole - a marker of partial pressure of oxygen. The levels of pimonidazole staining intensity were used to quantify changes in hypoxia gradients in terms of strong, medium and weak positive pixel fractions.

RESULTS

The pimonidazole staining ratio of viable control tumour tissue to viable tissue in tumours that were ablated was 0.7 for weak staining, 2.7 for medium staining and 8.0 (p < 0.03) for strong pimonidazole staining.

CONCLUSION

This shift of pimonidazole staining toward lower intensity pixels in the remaining tumour indicates that tumour ablation with CITT may increase radiosensitivity of the remaining tumour tissue and presents a rationale for combination therapy.