Comparative dosimetrical analysis of intensity-modulated arc therapy, CyberKnife therapy and image-guided interstitial HDR and LDR brachytherapy of low risk prostate cancer

Background: The objective of the study was to dosimetrically compare the intensity-modulated-arc-therapy (IMAT), CyberKnife therapy (CK), single fraction interstitial high-dose-rate (HDR) and low-dose-rate (LDR) brachytherapy (BT) in low-risk prostate cancer. Materials and methods: Treatment plans of ten patients treated with CK were selected and additional plans using IMAT, HDR and LDR BT were created on the same CT images. The prescribed dose was 2.5/70 Gy in IMAT, 8/40 Gy in CK, 21 Gy in HDR and 145 Gy in LDR BT to the prostate gland. EQD2 dose-volume parameters were calculated for each technique and compared. Results: EQD2 total dose of the prostate was significantly lower with IMAT and CK than with HDR and LDR BT, D90 was 79.5 Gy, 116.4 Gy, 169.2 Gy and 157.9 Gy (p < 0.001). However, teletherapy plans were more conformal than BT, COIN was 0.84, 0.82, 0.76 and 0.76 (p < 0.001), respectively. The D2 to the rectum and bladder were lower with HDR BT than with IMAT, CK and LDR BT, it was 66.7 Gy, 68.1 Gy, 36.0 Gy and 68.0 Gy (p = 0.0427), and 68.4 Gy, 78.9 Gy, 51.4 Gy and 70.3 Gy (p = 0.0091) in IMAT, CK, HDR and LDR BT plans, while D0.1 to the urethra was lower with both IMAT and CK than with BTs: 79.9 Gy, 88.0 Gy, 132.7 Gy and 170.6 Gy (p < 0.001). D2 to the hips was higher with IMAT and CK, than with BTs: 13.4 Gy, 20.7 Gy, 0.4Gy and 1.5 Gy (p < 0.001), while D2 to the sigmoid, bowel bag, testicles and penile bulb was higher with CK than with the other techniques. Conclusions: HDR monotherapy yields the most advantageous dosimetrical plans, except for the dose to the urethra, where IMAT seems to be the optimal modality in the radiotherapy of low-risk prostate cancer

External beam accelerated partial breast irradiation: dosimetric assessment of conformal and three different intensity modulated techniques

Background The aim of the study was to evaluate and compare four different external beam radiotherapy techniques of accelerated partial breast irradiation (APBI) considering target coverage, dose to organs at risk and overall plan quality. The investigated techniques were three dimensional conformal radiotherapy (3D-CRT), "step and shoot" (SS) and "sliding window" (SW) intensity-modulated radiotherapy (IMRT), intensity-modulated arc therapy (RA). Patients and methods CT scans of 40 APBI patients were selected for the study. The planning objectives were set up according to the international recommendations. Homogeneity, conformity and plan quality indices were calculated from volumetric and dosimetric parameters of target volumes and organs at risk. The total monitor units and feasibility were also investigated. Results There were no significant differences in the coverage of the target volume between the techniques. The homogeneity indices of 3D-CRT, SS, SW and RA plans were 0.068, 0.074, 0.058 and 0.081, respectively. The conformation numbers were 0.60, 0.80, 0.82 and 0.89, respectively. The V50% values of the ipsilateral breast for 3D-CRT, SS, SW and RA were 47.5%, 40.2%, 39.9% and 31.6%, respectively. The average V10% and V40% values of ipsilateral lung were 13.1%, 28.1%, 28%, 36% and 2.6%, 1.9%, 1.9%, 3%, respectively. The 3D-CRT technique provided the best heart protection, especially in the low dose region. All contralateral organs received low doses. The SW technique achieved the best plan quality index (PQI). Conclusions Good target volume coverage and tolerable dose to the organs at risk are achievable with all four techniques. Taking into account all aspects, we recommend the SW IMRT technique for APBI

Kis és közepes kockázatú prosztatarákos betegek sztereotaxiás sugárkezelése CyberKnife gyorsítóval: korai radiogén mellékhatások

We report implementation of stereotactic body radiotherapy (SBRT) for the treatment of early, localized prostate cancer patients, and acute side effects caused by radiation therapy. Between February 2018 and July 2018, 36 prostate cancer patients were treated with SBRT. Treatments were performed with "CyberKnife M6" linear accelerator. In low-risk patients 8 Gy was delivered to the prostate in each fraction. For intermediate risk, 8 Gy to the prostate and 6.5 Gy to the seminal vesicles were delivered by each fraction with a simultaneous integrated boost technique. A total of 5 fractions (total dose 40 Gy) were given every second working days. Acute radiogenic genitourinary (GU) and gastrointestinal (GI) side effects were assessed using the Radiation Therapy Oncology Group (RTOG) score. The duration of radiotherapy was 1 week and 3 days. The frequency of acute radiogenic side effects was as follows: GU grade 0: 13.9%, grade I: 30.6%, grade II: 52.8%, grade III: 2.7%. GI grade 0: 55.5%, grade I: 30.6%, grade II: 13.9%, grade III: 0%. Grade IV-V side effects were not observed. SBRT appears to be a safe and well tolerated treatment in patients with early stage, localized prostate cancer

Izominvazív hólyagrák képvezérelt sugárkezelése intravesicalisan befecskendezett lipiodolos jelöléssel: A hólyagmegtartó kezelés új lehetősége.

INTRODUCTION AND AIM: To implement lipiodol as a fiducial marker of the tumor bed for image-guided radiotherapy with simultaneous integrated boost technique as part of radiochemotherapy for muscle invasive bladder tumors. METHOD: Since April 2016, radiochemotherapy was performed in 3 male patients with muscle invasive, transitional cell bladder carcinoma. Prior to radiochemotherapy, tumor bed resection was performed for each patient, at the same time 10 ml of lipiodol solution was injected submucosally into the resection site, thus marking the tumor bed for escalated dose irradiation. During radiochemotherapy 51 Gy (1.7 Gy/die) to the pelvis, 57 Gy (1.9 Gy/die) to the whole bladder, and 63 Gy (2.1 Gy/die) to the lipiodol-labeled tumor bed was delivered with simultaneous integrated boost technique. The accuracy of the irradiation was controlled by daily kilovoltage CT. Early radiogenic urogenital and gastrointestinal side effects were recorded according to Radiation Therapy Oncology Group side-effects grading recommendation. RESULTS: Substantial perioperative side effect or toxicity were not observed during and after the injection of lipiodol. The prescribed dose was successfully delivered in all patients. Radiotherapy duration was 6 weeks. The lipiodol-labeled tumor bed was clearly visible on daily kilovoltage cone beam CT. In one patient grade II cystitis and proctitis was observed, another patient experienced only grade I cystitis. These complaints improved with symptomatic medication. In the third patient no significant side effect occurred. CONCLUSIONS: The injection of lipiodol into the bladder wall is a safe technique, without any perioperative toxicity or complication. The tumor bed demarcated by lipiodol was visible both on treatment planning and kilovoltage CTs. The total treatment time was shortened by 4 days. The treatment was well tolerated, early side effects were moderate, or slight. Orv Hetil. 2017; 158(51): 2041-2047

Második emlőmegtartó műtét és szövetközi sugárkezelés az emlődaganat lokális kiújulásának kezelésére. Ötéves eredmények = Second breast conserving surgery and interstitial radiotherapy for the treatment of breast tumor local recurrences. Five-year results

Absztrakt: Bevezetés és célkitűzés: Második emlőmegtartó műtét és nagy dózisteljesítményű szövetközi sugárkezelés eredményeinek bemutatása azonos oldali emlődaganat kiújulása miatt kezelt betegeknél. Módszer: Korai invazív emlőrák előzetes emlőmegtartó kezelése után jelentkező helyi daganatkiújulás miatt 1999 és 2015 között 33 betegnél végeztünk második emlőmegtartó műtétet perioperatív szövetközi sugárkezeléssel. A második emlőmegtartó műtét során a tumorágyba átlagosan 8 (tartomány: 4–24) darab flexibilis katétert ültettünk be. A perioperatív időszakban a tumorágy és annak 1–2 cm-es biztonsági zónájának területére adott összdózis 22 Gy volt (5 × 4,4 Gy, 3 nap alatt). Adjuváns szisztémás kezelésként 24 beteg (73%) egyedüli endokrin kezelésben, 6 beteg (18%) pedig kemoterápiában részesült. A túlélési eredményeket a Kaplan–Meier-módszerrel elemeztük. A késői mellékhatásokat és a kozmetikai eredményeket feljegyeztük. Eredmények: A második emlőmegtartó kezeléstől számított követési idő középértéke 61 hónap (tartomány: 26–189 hónap) volt. A követési idő alatt 4 betegnél (12,1%) alakult ki második lokális recidíva. A második helyi daganatkiújulás, a regionális daganatkiújulás és a távoli áttétképződés ötéves valószínűsége 6,3%, 6,1% és 14,9% volt, azonos sorrendben. Az ötéves betegségmentes, daganatspecifikus és teljes túlélés 76,2%, 92,4% és 89,2% volt. Kiváló, jó, megfelelő és rossz kozmetikai eredményt 4 (12%), 19 (58%), 4 (12%) és 6 (18%) betegnél állapítottunk meg. Grade 2-es és 3-as fibrosis 9 (27%) és 1 (3%) betegnél alakult ki. Tünetmentes zsírnekrózist 7 (21%) betegnél figyeltünk meg. Következtetés: A második emlőmegtartó műtét perioperatív szövetközi sugárkezeléssel biztonságos lehetőség az emlődaganat helyi kiújulásának kezelésére. A szövetközi sugárkezelés elfogadható kozmetikai eredmények és kevés késői mellékhatás mellett csökkentheti a második lokális kiújulás valószínűségét, így válogatott esetekben a standard mastectomiát helyettesítheti. Orv Hetil. 2018; 159(11): 430–438. | Abstract: Introduction and aim: To report the clinical outcomes of second breast-conserving therapy with perioperative interstitial radiotherapy for the treatment of ipsilateral breast tumor recurrences. Method: Between 1999 and 2015, 33 patients, presenting with an ipsilateral breast tumor recurrence after previous breast conserving therapy, were salvaged by re-excision and perioperative high-dose-rate interstitial brachytherapy. A median of 8 (range: 4–24) catheters were implanted into the tumor bed intraoperatively. A total dose of 22 Gy in 5 fractions of 4.4 Gy was delivered to the tumor bed with a margin of 1–2 cm, on 3 consecutive days. The adjuvant systemic treatments consisted of hormonal therapy for 24 patients (73%) and chemotherapy for 6 patients (18%). The survival results were estimated by the Kaplan–Meier method. Late side effects and cosmetic results were also registered. Results: The median follow-up time following the second breast conserving therapy was 61 months (range: 26–189 months). During the follow-up, 4 patients (12.1%) developed second local recurrence. The five-year actuarial rates of the second local, regional and distant recurrence were 6.3%, 6.1%, and 14.9%, respectively. The five-year probabilities of disease-free, cancer-specific and overall survival were 76.2%, 92.4%, and 89.2%, respectively. Four (12%), 19 (58%), 4 (12%) and 6 (18%) patients had excellent, good, fair and poor cosmetic results, respectively. Grade 2 and 3 fibrosis developed in 9 (27%) and 1 (3%) patients. Asymptomatic fat necrosis was detected in 7 (21%) women. Conclusion: Second breast conserving therapy with perioperative high-dose-rate interstitial brachytherapy is a safe and feasible option for the management of ipsilateral breast tumor recurrences. Interstitial brachytherapy may decrease the risk of second local relapse with acceptable cosmetic results and low rate of late side effects. Hence, in selected cases it can provide a feasible alternative to salvage mastectomy. Orv Hetil. 2018; 159(11): 430–438

CyberKnife versus multicatheter interstitial brachytherapy for accelerated partial breast irradiation: a dosimetrical assessment with focus on organs at risk

Background: The purpose of the study was to dosimetrically compare multicatheter interstitial brachytherapy (MIBT) and stereotactic radiotherapy with CyberKnife (CK) for accelerated partial breast irradiation with special focus on dose to organs at risk (OARs). Materials and methods: Treatment plans of thirty-one patients treated with MIBT were selected and additional CK plans were created on the same CT images. The OARs included ipsilateral non-target and contralateral breast, ipsilateral and contralateral lung, skin, ribs, and heart for left sided cases. The fractionation was identical (4 x 6.25 Gy). Dose-volume parameters were calculated for both techniques and compared. Results: The D90 of the PTV for MIBT and CK were similar (102.4% vs. 103.6%, p = 0.0654), but in COIN the MIBT achieved lower value (0.75 vs. 0.91, p < 0.001). Regarding the V100 parameter of non-target breast CK performed slightly better than MIBT (V100: 1.1% vs. 1.6%), but for V90, V50 and V25 MIBT resulted in less dose. Every examined parameter of ipsilateral lung, skin, ribs and contralateral lung was significantly smaller for MIBT than for CK. Protection of the heart was slightly better with MIBT, but only the difference of D2cm3 was statistically significant (17.3% vs. 20.4%, p = 0.0311). There were no significant differences among the dose-volume parameters of the contralateral breast. Conclusion: The target volume can be properly irradiated by both techniques with high conformity and similar dose to the OARs. MIBT provides more advantageous plans than CK, except for dose conformity and the dosimetry of the heart and contralateral breast. More studies are needed to analyze whether these dosimetrical findings have clinical significance

Májáttétes betegek sztereotaxiás ablatív sugárkezelésével (SABRT) elért első eredményeink

Recently the prevalence of oligometastatic patients is increasing. A common site of distant spread is the liver. The standard of care is curative surgical resection, however, the resecability rate is only 10-20%. Alternatively, radiofrequency ablation (RFA) or transarterial chemoembolization (TACE) may be used. Stereotactic ablative body radiotherapy (SABRT) makes it possible to deliver curative radiation dose without radiation injury to the healthy liver tissue. We delivered SABRT to three patients with inoperable hepatic metastases. The primary tumors were rectal (2) and lung (1). The dose was 3x20 Gy every other day. We observed one grade 1 side effect. All the metastases showed complete remission and no local recurrence or late side effect occurred during the one year of follow-up. One patient is tumor-free, one has stable disease, in one patient two new hepatic metastases appeared and receives chemo-biological therapy. SABRT of liver metastases is safe and highly effective. It can be expected that in the near future it will become one of the standard treatments of hepatic tumors