Concurrent chemoradiotherapy with gemcitabine plus regional hyperthermia for locally advanced pancreatic carcinoma: initial experience

Hyperthermia combined with chemotherapy vs chemotherapy in patients with advanced pancreatic cancer: A multicenter retrospective observational comparative study

BACKGROUND

Several studies report the useful therapeutic results of regional hyperthermia in association with chemotherapy (CHT) and radiotherapy for the treatment of pancreatic cancer. Modulated electro-hyperthermia (mEHT) is a new hyperthermia technique that induces immunogenic death or apoptosis of pancreatic cancer cells in laboratory experiments and increases tumor response rate and survival in pancreatic cancer patients, offering beneficial therapeutic effects against this severe type of cancer.

AIM

To assess survival, tumor response and toxicity of mEHT alone or combined with CHT compared with CHT for the treatment of locally advanced or metastatic pancreatic cancer.

METHODS

This was a retrospective data collection on patients affected by locally advanced or metastatic pancreatic cancer (stage III and IV) performed in 9 Italian centers, members of International Clinical Hyperthermia Society-Italian Network. This study included 217 patients, 128 (59%) of them were treated with CHT (no-mEHT) and 89 (41%) patients received mEHT alone or in association with CHT. mEHT treatments were performed applying a power of 60-150 watts for 40-90 min, simultaneously or within 72 h of administration of CHT.

RESULTS

Median patients' age was 67 years (range 31-92 years). mEHT group had a median overall survival greater than non-mEHT group (20 mo, range 1.6-24, vs 9 mo, range 0.4-56.25, P < 0.001). mEHT group showed a higher number of partial responses (45% vs 24%, P = 0.0018) and a lower number of progressions (4% vs 31%, P < 0.001) than the no-mEHT group, at the three months follow-up. Adverse events were observed as mild skin burns in 2.6% of mEHT sessions.

CONCLUSION

mEHT seems safe and has beneficial effects on survival and tumor response of stage III-IV pancreatic tumor treatment. Further randomized studies are warranted to confirm or not these results.

Clinical Evidence for Thermometric Parameters to Guide Hyperthermia Treatment

Hyperthermia (HT) is a cancer treatment modality which targets malignant tissues by heating to 40-43 °C. In addition to its direct antitumor effects, HT potently sensitizes the tumor to radiotherapy (RT) and chemotherapy (CT), thereby enabling complete eradication of some tumor entities as shown in randomized clinical trials. Despite the proven efficacy of HT in combination with classic cancer treatments, there are limited international standards for the delivery of HT in the clinical setting. Consequently, there is a large variability in reported data on thermometric parameters, including the temperature obtained from multiple reference points, heating duration, thermal dose, time interval, and sequence between HT and other treatment modalities. Evidence from some clinical trials indicates that thermal dose, which correlates with heating time and temperature achieved, could be used as a predictive marker for treatment efficacy in future studies. Similarly, other thermometric parameters when chosen optimally are associated with increased antitumor efficacy. This review summarizes the existing clinical evidence for the prognostic and predictive role of the most important thermometric parameters to guide the combined treatment of RT and CT with HT. In conclusion, we call for the standardization of thermometric parameters and stress the importance for their validation in future prospective clinical studies.

Modulated Electro-Hyperthermic (mEHT) Treatment in the Therapy of Inoperable Pancreatic Cancer Patients-A Single-Center Case-Control Study

Our present oncological treatment arsenal has limited treatment options for pancreatic ductal adenocarcinoma (PDAC). Extended reviews have shown the benefits of hyperthermia for PDAC, supporting the perspectives with the improvements of the treatment possibilities.

METHODS

A retrospective single-center case-control study was conducted with the inclusion of 78 inoperable PDAC patients. Age-, sex-, chemotherapy-, stage-, and ascites formation-matched patients were assigned to two equal groups based on the application of modulated electro-hyperthermia (mEHT). The EHY2030 mEHT device was used.

RESULTS

A trend in favor of mEHT was found in overall survival (p = 0.1420). To further evaluate the potential beneficial effects of mEHT, the presence of distant metastasis or ascites in the patients' oncological history was investigated. Of note, mEHT treatment had a favorable effect on patients' overall survival in metastatic disease (p = 0.0154), while less abdominal fluid responded to the mEHT treatment in a more efficient way (p ≤ 0.0138).

CONCLUSION

mEHT treatment was associated with improved overall survival in PDAC in our single-center retrospective case-control study. The outcome measures encourage us to design a randomized prospective clinical study to further confirm the efficiency of mEHT in this patient cohort.

Evidence based tools to improve efficiency of currently administered oncotherapies for tumors of the hepatopancreatobiliary system

Hepatopancreatobiliary tumors are challenging to treat, and the advanced or metastatic forms have a very low 5-year survival rate. Several drug combinations have been tested, and new therapeutic approaches have been introduced in the last decades, including radiofrequency and heat based methods. Hyperthermia is the artificial heating of tumors by various biophysical methods that may possess immunostimulant, tumoricidal, and chemoradiotherapy sensitizer effects. Both whole-body and regional hyperthermia studies have been conducted since the 1980s after the introduction of deep-seated tumor hyperthermia techniques. Results of the effects of hyperthermia in hepatocellular and pancreatic cancer are known from several studies. Hyperthermia in biliary cancers is a less investigated area. High local and overall responses to treatment, increased progression-free and overall survival, and improved laboratory and quality-of-life results are associated with hyperthermia in all three tumor types. With the evolution of chemotherapeutic agents and the introduction of newer techniques, the combination of adjuvant hyperthermia with those therapies is advantageous and has not been associated with an increase in alarming adverse effects. However, despite the many positive effects of hyperthermia, its use is still only known at the experimental level, and its concomitant utilization in routine cancer treatment is not certain because of the lack of thorough clinical studies.

Heating technology for malignant tumors: a review

The therapeutic application of heat is very effective in cancer treatment. Both hyperthermia, i.e., heating to 39-45 °C to induce sensitization to radiotherapy and chemotherapy, and thermal ablation, where temperatures beyond 50 °C destroy tumor cells directly are frequently applied in the clinic. Achievement of an effective treatment requires high quality heating equipment, precise thermal dosimetry, and adequate quality assurance. Several types of devices, antennas and heating or power delivery systems have been proposed and developed in recent decades. These vary considerably in technique, heating depth, ability to focus, and in the size of the heating focus. Clinically used heating techniques involve electromagnetic and ultrasonic heating, hyperthermic perfusion and conductive heating. Depending on clinical objectives and available technology, thermal therapies can be subdivided into three broad categories: local, locoregional, or whole body heating. Clinically used local heating techniques include interstitial hyperthermia and ablation, high intensity focused ultrasound (HIFU), scanned focused ultrasound (SFUS), electroporation, nanoparticle heating, intraluminal heating and superficial heating. Locoregional heating techniques include phased array systems, capacitive systems and isolated perfusion. Whole body techniques focus on prevention of heat loss supplemented with energy deposition in the body, e.g., by infrared radiation. This review presents an overview of clinical hyperthermia and ablation devices used for local, locoregional, and whole body therapy. Proven and experimental clinical applications of thermal ablation and hyperthermia are listed. Methods for temperature measurement and the role of treatment planning to control treatments are discussed briefly, as well as future perspectives for heating technology for the treatment of tumors.

Effect of gastrointestinal gas on the temperature distribution in pancreatic cancer hyperthermia treatment planning

PURPOSE

In pancreatic cancer treatment, hyperthermia can be added to increase efficacy of chemo- and/or radiotherapy. Gas in stomach, intestines and colon is often in close proximity to the target volume. We investigated the impact of variations in gastrointestinal gas (GG) on temperature distributions during simulated hyperthermia treatment (HT).

METHODS

We used sets of one CT and eight cone-beam CT (CBCT) scans obtained prior to/during fractionated image-guided radiotherapy in four pancreatic cancer patients. In Plan2Heat, we simulated locoregional heating by an ALBA-4D phased array radiofrequency system and calculated temperature distributions for (i) the segmented CT (sCT), (ii) sCT with GG replaced by muscle (sCT₀), (iii) sCT₀ with eight different GG distributions as visible on CBCT inserted (sCT_CBCT). We calculated cumulative temperature-volume histograms for the clinical target volume (CTV) for all ten temperature distributions for each patient and investigated the relationship between GG volume and change in ΔT₅₀ (temperature increase at 50% of CTV volume). We determined location and volume of normal tissue receiving a high thermal dose.

RESULTS

GG volume on CBCT varied greatly (9-991 cm³). ΔT₅₀ increased for increasing GG volume; maximum ΔT₅₀ difference per patient was 0.4-0.6 °C. The risk for GG-associated treatment-limiting hot spots appeared low. Normal tissue high-temperature regions mostly occurred anteriorly; their volume and maximum temperature showed moderate positive correlations with GG volume, while fat-muscle interfaces were associated with higher risks for hot spots.

CONCLUSIONS

Considerable changes in volume and position of gastrointestinal gas can occur and are associated with clinically relevant tumor temperature differences.

A Narrative Review of Regional Hyperthermia: Updates From 2010 to 2019

The role of hyperthermia (HT) in cancer therapy and palliative care has been discussed for years in the literature. There are plenty of articles that show good feasibility of HT and its efficacy in terms of tumor response and survival improvements. Nevertheless, HT has never gained enough interest among oncologists to become a standard therapy in clinical practice. The main advantage of HT is the enhancement of chemotherapy (CHT), radiotherapy (RT), chemoradiotherapy (CRT), and immunotherapy benefits. This effect has been confirmed in several types of tumors: esophageal, gastrointestinal, pancreas, breast, cervix, head and neck, and bladder cancers, and soft tissue sarcoma. HT effects include oxygenation and perfusion changes, DNA repair inhibition and immune system activation as a consequence of new antigen exposure. The literature shows a wide variety of randomized, nonrandomized, and observational studies and both prospective and retrospective data to confirm the advantage of HT association to CHT and RT. There are still many ongoing trials on this subject. This article summarizes the available literature on HT in order to update the current knowledge on HT use in association with RT and/or CHT from 2010 up to 2019.

Concentration changes in gemcitabine and its metabolites after hyperthermia in pancreatic cancer cells assessed using RP-HPLC

Background

Gemcitabine (2′,2′-difluoro-2′-deoxycytidine;dFdC) is a first-line chemotherapy drug for pancreatic cancer. Recently, a synergistic anti-tumor treatment of dFdC and hyperthermia has achieved good clinical results, but there are few reports on the molecular mechanism influenced by hyperthermia. This study is an initial exploration of the effects of hyperthermia on changes in the concentration of dFdC and its metabolites in pancreatic cancer cells. The aim is to provide a theoretical basis for clinical detection and pharmacokinetic research.

Methods

PANC-1 cells at logarithmic growth phase were used as the experimental object. The MTT assay was performed to determine the half maximal inhibitory concentration (IC₅₀) of dFdC. After PANC-1 cells were cultured in DMEM medium containing IC₅₀dFdC and treated with hyperthermia at 41 °C or 43 °C, changes in the concentration of dFdC, 2′,2′-difluorodeoxyuridine (dFdU) and difluorodeoxycytidine triphosphate (dFdCTP) in the cells were tested using an optimized reverse phase high-performance liquid chromatography (RP-HPLC) protocol.

Results

We found that 41 °C and 43 °Chyperthermia gave rise to a decrease in dFdC and dFdU content. At 41 °C, the levels respectively fell to 9.28 and 30.93% of the baseline, and at 43 °C, to 24.76 and 57.80%, respectively. The dFdCTP content increased by 21.82% at 41 °C and 42.42% at 43 °C.

Conclusion

The two heat treatments could alter the mechanism of dFdC metabolism in PANC-1 cells. The effect of 43 °C hyperthermia is more significant. Our observations may be instrumental to explaining the higher anti-tumor efficacy of this combination therapy.

Modulated Electro-Hyperthermia as Palliative Treatment for Pancreatic Cancer: A Retrospective Observational Study on 106 Patients

Background: Pancreatic adenocarcinoma has a poor prognosis, resulting in a <10% survival rate at 5 years. Modulated electro-hyperthermia (mEHT) has been increasingly used for pancreatic cancer palliative care and therapy. Objective: To monitor the efficacy and safety of mEHT for the treatment of advanced pancreatic cancer. Methods: We collected data retrospectively on 106 patients affected by stage III-IV pancreatic adenocarcinoma. They were divided into 2 groups: patients who did not receive mEHT (no-mEHT) and patients who were treated with mEHT. We performed mEHT applying a power of 60 to 150 W for 40 to 90 minutes. The mEHT treatment was associated with chemotherapy and/or radiotherapy for 33 (84.6%) patients, whereas 6 (15.4%) patients received mEHT alone. The patients of the no-mEHT group received chemotherapy and/or radiotherapy in 55.2% of cases. Results: Median age of the sample was 65.3 years (range = 31-80 years). After 3 months of therapy, the mEHT group had partial response in 22/34 patients (64.7%), stable disease in 10/34 patients (29.4%), and progressive disease in 2/34 patients (8.3%). The no-mEHT group had partial response in 3/36 patients (8.3%), stable disease in 10/36 patients (27.8%), and progressive disease in 23/36 patients (34.3%). The median overall survival of the mEHT group was 18.0 months (range = 1.5-68.0 months) and 10.9 months (range = 0.4-55.4 months) for the non-mEHT group. Conclusions: mEHT may improve tumor response and survival of pancreatic cancer patients.

The clinical benefit of hyperthermia in pancreatic cancer: a systematic review

OBJECTIVE

In pancreatic cancer, which is therapy resistant due to its hypoxic microenvironment, hyperthermia may enhance the effect of radio(chemo)therapy. The aim of this systematic review is to investigate the validity of the hypothesis that hyperthermia added to radiotherapy and/or chemotherapy improves treatment outcome for pancreatic cancer patients.

METHODS AND MATERIALS

We searched MEDLINE and Embase, supplemented by handsearching, for clinical studies involving hyperthermia in pancreatic cancer patients. The quality of studies was evaluated using the Oxford Centre for Evidence-Based Medicine levels of evidence. Primary outcome was treatment efficacy; we calculated overall response rate and the weighted estimate of the population median overall survival (m_p) and compared these between hyperthermia and control cohorts.

RESULTS

Overall, 14 studies were included, with 395 patients with locally advanced and/or metastatic pancreatic cancer of whom 248 received hyperthermia. Patients were treated with regional (n = 189), intraoperative (n = 39) or whole-body hyperthermia (n = 20), combined with chemotherapy, radiotherapy or both. Quality of the studies was low, with level of evidence 3 (five studies) and 4. The six studies including a control group showed a longer m_p in the hyperthermia groups than in the control groups (11.7 vs. 5.6 months). Overall response rate, reported in three studies with a control group, was also better for the hyperthermia groups (43.9% vs. 35.3%).

CONCLUSIONS

Hyperthermia, when added to chemotherapy and/or radiotherapy, may positively affect treatment outcome for patients with pancreatic cancer. However, the quality of the reviewed studies was limited and future randomised controlled trials are needed to establish efficacy.

Designing a bio-inspired biomimetic in vitro system for the optimization of ex vivo studies of pancreatic cancer

Pancreatic cancer is one of the most aggressive and lethal human malignancies. Drug therapies and radiotherapy are used for treatment as adjuvants to surgery, but outcomes remain disappointing. Advances in tissue engineering suggest that 3D cultures can reflect the in vivo tumor microenvironment and can guarantee a physiological distribution of oxygen, nutrients, and drugs, making them promising low-cost tools for therapy development. Here, we review crucial structural and environmental elements that should be considered for an accurate design of an ex vivo platform for studies of pancreatic cancer. Furthermore, we propose environmental stress response biomarkers as platform readouts for the efficient control and further prediction of the pancreatic cancer response to the environmental and treatment input.

Overexpression of heat shock protein 27 (HSP27) increases gemcitabine sensitivity in pancreatic cancer cells through S-phase arrest and apoptosis

We previously established a role for HSP27 as a predictive marker for therapeutic response towards gemcitabine in pancreatic cancer. Here, we investigate the underlying mechanisms of HSP27-mediated gemcitabine sensitivity. Utilizing a pancreatic cancer cell model with stable HSP27 overexpression, cell cycle arrest and apoptosis induction were analysed by flow cytometry, nuclear staining, immunoblotting and mitochondrial staining. Drug sensitivity studies were performed by proliferation assays. Hyperthermia was simulated using mild heat shock at 41.8°C. Upon gemcitabine treatment, HSP27-overexpressing cells displayed an early S-phase arrest subsequently followed by a strongly increased sub-G1 fraction. Apoptosis was characterized by PARP-, CASPASE 3-, CASPASE 8-, CASPASE 9- and BIM- activation along with a mitochondrial membrane potential loss. It was reversible through chemical caspase inhibition. Importantly, gemcitabine sensitivity and PARP cleavage were also elicited by heat shock-induced HSP27 overexpression, although to a smaller extent, in a panel of pancreatic cancer cell lines. Finally, HSP27-overexpressing pancreatic cancer cells displayed an increased sensitivity also towards death receptor-targeting agents, suggesting another pro-apoptotic role of HSP27 along the extrinsic apoptosis pathway. Taken together, in contrast to the well-established anti-apoptotic properties of HSP27 in cancer, our study reveals novel pro-apoptotic functions of HSP27—mediated through both the intrinsic and the extrinsic apoptotic pathways—at least in pancreatic cancer cells. HSP27 could represent a predictive marker of therapeutic response towards specific drug classes in pancreatic cancer and provides a novel molecular rationale for current clinical trials applying the combination of gemcitabine with regional hyperthermia in pancreatic cancer patients.

Intrabiliary RF heat-enhanced local chemotherapy of a cholangiocarcinoma cell line: monitoring with dual-modality imaging--preclinical study

PURPOSE

To determine whether magnetic resonance (MR) imaging heating guidewire-mediated radiofrequency (RF) hyperthermia could enhance the therapeutic effect of gemcitabine and 5-fluorouracil (5-FU) in a cholangiocarcinoma cell line and local deposit doses of chemotherapeutic drugs in swine common bile duct (CBD) walls.

MATERIALS AND METHODS

The animal protocol was approved by the institutional animal care and use committee. Green fluorescent protein-labeled human cholangiocarcinoma cells and cholangiocarcinomas in 24 mice were treated with (a) combination therapy with chemotherapy (gemcitabine and 5-FU) plus RF hyperthermia, (b) chemotherapy only, (c) RF hyperthermia only, or (d) phosphate-buffered saline. Cell proliferation was quantified, and tumor changes over time were monitored with 14.0-T MR imaging and optical imaging. To enable further validation of technical feasibility, intrabiliary local delivery of gemcitabine and 5-FU was performed by using a microporous balloon with (eight pigs) or without (eight pigs) RF hyperthermia. Chemotherapy deposit doses in the bile duct walls were quantified by means of high-pressure liquid chromatography. The nonparametric Mann-Whitney U test and the paired-sample Wilcoxon signed rank test were used for data analysis.

RESULTS

Combination therapy induced lower mean levels of cell proliferation than chemotherapy only and RF hyperthermia only (0.39 ± 0.13 [standard deviation] vs 0.87 ± 0.10 and 1.03 ± 0.13, P < .001). Combination therapy resulted in smaller relative tumor volume than chemotherapy only and RF hyperthermia only (0.65 ± 0.03 vs 1.30 ± 0.021 and 1.37 ± 0.05, P = .001). Only in the combination therapy group did both MR imaging and optical imaging show substantial decreases in apparent diffusion coefficients and fluorescent signals in tumor masses immediately after the treatments. Chemotherapy quantification showed a higher average drug deposit dose in swine CBD walls with intrabiliary RF hyperthermia than without it (gemcitabine: 0.32 mg/g of tissue ± 0.033 vs 0.260 mg/g ± 0.030 and 5-FU: 0.660 mg/g ± 0.060 vs 0.52 mg/g ± 0.050, P < .05).

CONCLUSION

The use of intrabiliary MR imaging heating guidewire-mediated RF hyperthermia can enhance the chemotherapeutic effect on a human cholangiocarcinoma cell line and local drug deposition in swine CBD tissues.

Heat shock protein 27 as a prognostic and predictive biomarker in pancreatic ductal adenocarcinoma

A role of heat shock protein 27 (HSP27) as a potential biomarker has been reported in various tumour entities, but comprehensive studies in pancreatic cancer are lacking. Applying tissue microarray (TMA) analysis, we correlated HSP27 protein expression status with clinicopathologic parameters in pancreatic ductal adenocarcinoma specimens from 86 patients. Complementary, we established HSP27 overexpression and RNA-interference models to assess the impact of HSP27 on chemo- and radiosensitivity directly in pancreatic cancer cells. In the TMA study, HSP27 expression was found in 49% of tumour samples. Applying univariate analyses, a significant correlation was found between HSP27 expression and survival. In the multivariate Cox-regression model, HSP27 expression emerged as an independent prognostic factor. HSP27 expression also correlated inversely with nuclear p53 accumulation, indicating either protein interactions between HSP27 and p53 or TP53 mutation-dependent HSP27-regulation in pancreatic cancer. In the sensitivity studies, HSP27 overexpression rendered HSP27 low-expressing PL5 pancreatic cancer cells more susceptible towards treatment with gemcitabine. Vice versa, HSP27 protein depletion in HSP27 high-expressing AsPC-1 cells caused increased gemcitabine resistance. Importantly, HSP27 expression was inducible in pancreatic cancer cell lines as well as primary cells. Taken together, our study suggests a role for HSP27 as a prognostic and predictive marker in pancreatic cancer. Assessment of HSP27 expression could thus facilitate the identification of specific patient subpopulations that might benefit from individualized treatment options. Additional studies need to clarify whether modulation of HSP27 expression could represent an attractive concept to support the incorporation of hyperthermia in clinical treatment protocols for pancreatic cancer.

Hyperthermia potentiates oncolytic herpes viral killing of pancreatic cancer through a heat shock protein pathway

BACKGROUND

Oncolytic herpes simplex virus-1 (HSV-1) is designed to specifically infect, replicate in, and lyse cancer cells. This study investigates a novel therapeutic regimen, combining the effects of NV1066 (a recombinant HSV-1) and hyperthermia in the treatment of pancreatic cancer.

METHODS

NV1066 is an attenuated HSV-1 that replicates in cells resistant to apoptosis. Heat shock protein 72 (Hsp72) is a member of a family of proteins that is upregulated after hyperthermic insult, lending cellular protection by inhibiting apoptosis. In these experiments, we test the hypothesis that increased Hsp72 expression in response to hyperthermia enhances anti-apoptotic mechanisms, thereby increasing viral replication and tumor cell kill. Hs 700T pancreatic cancer cells were treated with hyperthermia alone (42 degrees C), NV1066 alone, and combination therapy. Cell survival and viral growth were measured. The effect of siRNA-directed Hsp72 knockdown was also measured.

RESULTS

Combining hyperthermia and viral treatment produced a synergistic effect on cell kill. Viral growth increased greater than 6-fold in the presence of hyperthermia (P < .05). Hyperthermia alone showed minimal cytotoxic activity against Hs 700T cells, while NV1066 infection resulted in approximately 50% cell kill. The combination of hyperthermia and viral infection significantly increased cell kill to approximately 80% (P < .01). Hsp72 knockdown attenuated this synergistic effect.

CONCLUSION

Hyperthermia enhances NV1066 replication, thereby potentiating the viral oncolytic response against pancreatic cancer cells. This finding has potential clinical application in the use of heated perfusion or permissive hyperthermia for delivery of oncolytic viral therapies.