Hyperthermia – description of a method and a review of clinical applications

SummaryThe aim of this paper is to give a concise description of hyperthermia and a brief review of its clinical applications. Hyperthermia (HT, thermal therapy) is thought to be one of the cancer therapies and is considered to be an artificial way of increasing the body tissue temperature by delivering heat obtained from external sources to destroy cancerous cells or prevent their further growth. The first principles of hyperthermic biology are presented. The phenomena of thermotolerance and radiosensitization are briefly described, as well as the concept of thermal dose delivered to the tissues.Three main clinical applications of HT are presented. They include local, regional or part-body HT and whole-body HT that deliver heat to localized, advanced or deep-seated and disseminated malignancies, respectively, depending on location, depth and staging of the tumour. Energies used to apply heat to the tumour include microwaves, radiofrequency energy, ultrasound, infrared radiators and different kinds of hot sources (hot water, ferromagnetic seeds, nanoparticles, resistive implants). General indications for each HT subtype and possible combinations of HT with other cancer treatment modalities are presented.Substantially, HT is used as an adjuvant therapy and in such a role it is being evaluated in many clinical randomized trials throughout the scientific medical centres. Their first preliminary results are already available, but still time is needed to produce firm conclusions and strict indications for hyperthermia treatment

Thermally boosted interstitial high-dose-rate brachytherapy in high-risk early-stage breast cancer conserving therapy — large cohort long-term results

Background: Early-stage high-risk breast cancer (BC) is standardly treated with breast-conserving therapy (BCT), combined with systemic therapy and radiotherapy (RT) ± tumor bed boost, e.g., with interstitial high-dose-rate brachytherapy (HDR-BT). To improve local recurrence rate (LRR), BT radiosensitization (thermal boost, TB) with interstitial microwave hyperthermia (MWHT) may be an option. The paper aims to report a retrospective single-institutional study on 5- and 10-year local control (LC), distant metastasis-free survival (DMFS), disease-free survival (DFS), overall survival (OS), cosmetic outcome (CO), and late toxicity (fibrosis, fat necrosis) after thermally enhanced HDR-BT boost to the BC tumor bed. Materials and methods: In 2006–2018, 557 early-stage (I–IIIA) high-risk BC patients were treated with BCT. If indicated, they were administered systemic therapy, then referred for 40.0–50.0 Gy whole breast irradiation (WBI) and 10 Gy interstitial HDR-BT boost (group A). Eligible patients had a single MWHT session preceding BT (group B). Based on present risk factors (RF), medium-risk (1–2 RF) and high-risk subgroups (≥ 3 RF) were formed. Patients were standardly checked, and control mammography (MMG) was performed yearly. Breast cosmesis (Harvard scale) and fibrosis were recorded. LC, DMFS, DFS, and OS were statistically analyzed. Results: Out of 557 patients aged 57 years (26–84), 364 (63.4%) had interstitial HDR-BT boost (group A), and 193 (34.6%) were preheated with MWHT (group B). Patients in group B had a higher clinical stage and had more RFs. The median follow-up was 65.9. Estimated 5-year and 10-year LC resulted in 98.5% and 97.5%, respectively. There was no difference in LC, DMFS, DFS, and OS between groups A and B and between extracted high-risk subgroups A and B. Five- and ten-year OS probability was 95.4% and 88.0%, respectively, with no difference between groups A and B. Harvard criteria-based CO assessment revealed good/excellent cosmesis in 74.9–79.1%. Tumor bed hardening was present in 40.1–42.2%. Asymptomatic fat necrosis-related macrocalcifications were detected in 15.6%, more frequently in group B (p = 0.016). Conclusions: Thermally boosted or not, HDR-BT was locally highly effective as part of combined treatment. Five- and ten-year LC, DMFS, DFS, and OS were high and equally distributed between the groups, although TB was prescribed in more advanced one with more RFs. TB did not influence CO and fibrosis. TB added to late toxicity regarding asymptomatic fat necrosis detected on MMG

Hyperthermia – description of a method and a review of clinical applications

The aim of this paper is to give a concise description of hyperthermia and a brief review of its clinical applications. Hyperthermia (HT, thermal therapy) is thought to be one of the cancer therapies and is considered to be an artificial way of increasing the body tissue temperature by delivering heat obtained from external sources to destroy cancerous cells or prevent their further growth. The first principles of hyperthermic biology are presented. The phenomena of thermotolerance and radiosensitization are briefly described, as well as the concept of thermal dose delivered to the tissues.Three main clinical applications of HT are presented. They include local, regional or part-body HT and whole-body HT that deliver heat to localized, advanced or deep-seated and disseminated malignancies, respectively, depending on location, depth and staging of the tumour. Energies used to apply heat to the tumour include microwaves, radiofrequency energy, ultrasound, infrared radiators and different kinds of hot sources (hot water, ferromagnetic seeds, nanoparticles, resistive implants). General indications for each HT subtype and possible combinations of HT with other cancer treatment modalities are presented.Substantially, HT is used as an adjuvant therapy and in such a role it is being evaluated in many clinical randomized trials throughout the scientific medical centres. Their first preliminary results are already available, but still time is needed to produce firm conclusions and strict indications for hyperthermia treatment

CT-image based conformal high-dose-rate brachytherapy boost in the conservative treatment of stage I – II breast cancer – introducing the procedure

AimBreast-conserving surgery (BCS) followed by radiotherapy (RT) has become the standard treatment for the majority of patients with early breast cancer. With regard to boost technique some disagreements are found between groups that are emphasizing the value of electron boost treatment and groups pointing out the value of interstitial brachytherapy (BT) boost treatment. We present the preliminary results in treating selected patients with early-stage breast cancer using high-dose-rate brachytherapy (HDR-BT) as a boost after breast conservation therapy (BCT).Materials/MethodsBetween January 2006 and August 2007, a total of 58 female patients with first and second stage breast cancer underwent BCT. This therapeutic procedure involves BCS, whole breast radiation therapy (WBRT) and additional irradiation to the tumour bed (boost) using interstitial HDR-BT via flexible implant tubes. A 10 Gy boost dose was received by all patients. The treatment planning was based on CT-guided 3D (three-dimensional) reconstruction of the surgical clips, implant tubes and critical structures localization (skin and ribs). The accuracy of tumour bed localization, the conformity of planning target volume and treated volume were analyzed.ResultsThe evaluations of implant parameters involved the use of: dose volume histogram (DVH), the volume encompassed by the 100% reference isodose surface (V100%), the high dose volume calculation (V150%, V200%, V300%), the dose non-uniformity ratio (DNR), and the conformity index (COIN). Our results were as follows: the mean PTV volume, the mean high dose volume (V150%; V200%; V300%), the DNR and COIN mean value were estimated at 57.38, 42.98, 21.38, 7.90, 0.52 and 0.83 respectively.ConclusionsCT-guided 3D HDR-BT is most appropriate for planning the boost procedure after BT especially in large breast volume, in cases with a deep seated tumour bed, as well as in patients with high risk for local recurrences. This technique reduces the possibility of geographical miss. Moreover, better conformity could be achieved between planning the target volume and the treated volume, even at the cost of worse dose homogeneity. The irregular 3D shape of the target volume and the normal tissue structures can be correctly localized on the basis of visual information obtained from cross-sectional CT imaging. Better local control rate with fewer side effects might be achieved with this technique based on CT imaging

Permanent implants in treatment of prostate cancer

Low-dose rate brachytherapy (LDR – BT) is one of the radiation methods that is known for several years in treatment of localized prostate cancer. The main idea of this method is to implant small radioactive seeds as a source of radiation, directly into the prostate gland. LDR brachytherapy is applied as a monotherapy and also used along with external beam radiation therapy (EBRT) as a boost. In most cases it is used as a sole radical treatment modality, however not as a palliative treatment. The application of permanent seeds implants is a curative treatment alternative in patients with organ-confined cancer, without extracapsular extension of the tumour. Nowadays three kinds of radionuclide (I-125, Pd-103, Cs-131) are in use worldwide. This technique is particular favorite in United States, in Europe however, high-dose rate brachytherapy method (HDR BT) is more popular in early staged prostate cancer treatment (as a boost). HDR-BT monotherapy for early stage prostate cancer is still an investigational treatment. As monotherapy LDR-BT seems to be a reliable choice for early stage prostate cancer, according to low morbidity rate good results and short hospitalization. It is curative alternative of radical prostatectomy or external beam radiation (i.e. 3D CRT, IMRT) with comparable long-term survival and biochemical control and most favorable toxicity. The aim of this publication is to describe methods, indications, complications and selected results of prostate cancer LDR brachytherapy

Brachytherapy in breast cancer: an effective alternative

Breast conserving surgery (BCS) with following external beam radiation therapy (EBRT) of the conserved breast has become widely accepted in the last decades for the treatment of early invasive breast cancer. The standard technique of EBRT after BCS is to treat the whole breast up to a total dose of 42.5 to 50 Gy. An additional dose is given to treated volume as a boost to a portion of the breast. In the early stage of breast cancer, research has shown that the area requiring radiation treatment to prevent the cancer from local recurrence is the breast tissue that surrounds the area where the initial cancer was removed. Accelerated partial breast irradiation (APBI) is an approach that treats only the lumpectomy bed plus a 1-2 cm margin rather than the whole breast and as a result allows accelerated delivery of the radiation dose in four to five days. There has been a growing interest for APBI and various approaches have been developed under phase I-III clinical studies; these include multicatheter interstitial brachytherapy, balloon catheter brachytherapy, conformal external beam radiation therapy (3D-EBRT) and intra-operative radiation therapy (IORT). Balloon-based brachytherapy approaches include MammoSite, Axxent electronic brachytherapy, Contura, hybrid brachytherapy devices. Another indication for breast brachytherapy is reirradiation of local recurrence after mastectomy. Published results of brachytherapy are very promising. We discuss the current status, indications, and technical aspects of breast cancer brachytherapy