Accelerated Partial Breast Irradiation in the treatment of breast cancer — current status and treatment methods

Podstawowym powodem opracowania techniki przyspieszonego częściowego napromieniania raka piersi (AcceleratedPartial Breast Irradiation — APBI) było założenie, że prowadzi ono do uzyskania równorzędnego odsetkakontroli miejscowej wraz z mniejszą toksycznością leczenia w porównaniu z napromienianiem całej piersi wiązkamizewnętrznymi (Whole Breast Radiation Therapy — WBRT) po chirurgicznym leczeniu oszczędzającym (Breast ConservingSurgery — BCS). Jest to metoda radioterapii skierowana do wyselekcjonowanej grupy pacjentek we wczesnej faziezaawansowania choroby. Głównym powodem wprowadzenia do praktyki klinicznej APBI było niskie ryzyko wznowymiejscowej w tej samej piersi poza pierwotnie zajętym kwadrantem. Opublikowano szereg badań sugerującychmożliwość rezygnacji z WBRT. Dotychczas dostępne są wyniki 3 badań randomizowanych i 19 nierandomizowanych,w których badano skuteczność APBI. W poszczególnych badaniach klinicznych stosowano różne techniki APBI, dawkii frakcjonowanie, ale zasadnicza różnica w stosowanych technikach dotyczyła określenia obszaru do napromieniania(Clinical Target Volume — CTV i Planning Target Volume — PTV). Obecnie czekamy na wyniki siedmiu randomizowanychbadań klinicznych dotyczących zastosowania APBI w raku piersi po leczeniu oszczędzającym. W artykule dokonanoprzeglądu stosowanych technik, zasad kwalifi kacji oraz wyników leczenia metodą APBI.Breast conserving surgery (BCS) with following radiotherapy (EBRT) of the conserved breast became widely acceptedin the last decades for the treatment of early invasive breast cancer. The standard technique of EBRT after BCS is totreat the whole breast up to a total dose of 45 Gy to 50 Gy. Additional dose is given to the treated volume after EBRTto boost a portion of the breast to a higher dose. However, over the past 10 years, the application of radiotherapy inbreast cancer has changed. In early stage breast cancer, research has shown that the area requiring radiation treatmentto prevent the cancer from local recurrence is the breast tissue that surrounds the area where the initial cancerwas removed. Because this typically includes only a part of the breast, APBI is now used to treat the targeted portionof the breast and as a result allows accelerated delivery of the radiation dose in four to fi ve days. Published resultsof APBI techniques are very promising. In this article the current status, indications, technical aspects and recentlypublished results of APBI in breast cancer treatment are presented

Personalized Superficial HDR Brachytherapy—Dosimetric Verification of Dose Distribution with Lead Shielding of Critical Organs in the Head and Neck Region

Background: Surface brachytherapy, usually characterized by a high dose gradient, allows the dose to be precisely deposited in the irradiated area while protecting critical organs. When the lesion is located in the nasal or ocular region, the organ of vision must be protected. The aim of this study was to verify the dose distributions near critical organs in the head and neck region during a brachytherapy procedure using lead shielding of the eye. Methods: Anthropomorphic phantom using 3D-printing technology was prepared. The doses deposited at a point in the lens of the eye and on the surface of the eyelid, directly under the lead shield were calculated and measured using EBT3 radiochromic films. Comparison of doses planned in the treatment planning system using the TG-43 formalism, TG-186 formalism, and measured were also performed. Results: Comparing the planned and calculated doses with TG186 formalism it can be assumed that the use of lead shields is a method for protecting the organ of vision from the adverse effects of ionizing radiation. Conclusions: The decision to use a lead shield during facial surface brachytherapy procedures should be made on a patient-by-patient basis and based on model-based calculation methods recommended by TG186

Thermal Boost to Breast Tumor Bed—New Technique Description, Treatment Application and Example Clinical Results

(1) Current breast-conserving therapy for breast cancer consists of a combination of many consecutive treatment modalities. The most crucial goal of postoperative treatment is to eradicate potentially relapse-forming residual cancerous cells within the tumor bed. To achieve this, the HDR brachytherapy boost standardly added to external beam radiotherapy was enhanced with an initial thermal boost. This study presents an original thermal boost technique developed in the clinic. (2) A detailed point-by-point description of thermal boost application is presented. Data on proper patient selection, microwave thermal boost planning, and interstitial hyperthermia treatment delivery are supported by relevant figures and schemes. (3) Out of 1134 breast cancer patients who were administered HDR brachytherapy boost in the tumor bed, 262 were also pre-heated interstitially without unexpected complications. The results are supported by two example cases of hyperthermia planning and delivery. (4) Additional breast cancer interstitial thermal boost preceding HDR brachytherapy boost as a part of combined treatment in a unique postoperative setting was feasible, well-tolerated, completed in a reasonable amount of time, and reproducible. A commercially available interstitial hyperthermia system fit and worked well with standard interstitial brachytherapy equipment