5-Year Results of Pulsed Dose Rate Brachytherapy Applied as a Boost after Breast-Conserving Therapy in Patients at High Risk for Local Recurrence from Breast Cancer

Purpose: The aim of this study was to evaluate effect, toxicity, and cosmesis of a prospectively applied pulsed dose rate (PDR) brachytherapy boost schedule in patients with stage I/II/IIIa invasive breast cancer. Patients and Methods: A total of 113 patients were treated after breast-conserving surgery (BCS) and external beam radiotherapy (median 50 Gy, range 46-52). The boost dose was graded in accordance to the pathologic tumor characteristics: 20-25 Gy: incomplete resection (n = 34), vascular invasion (n = 27), close margin resection (n = 41); 15 Gy: T2G3 stage (n = 11). PDR brachytherapy (37 GBq, ¹⁹²Ir source) was carried out after geometric volume optimization with 1 Gy/pulse/h. The implantation and dose specification were performed similar to the rules of the Paris system. Results: The overall local failure rate after a median follow-up of 61 months was 4.4% (5/113). The actuarial 5- and 8-year local recurrence-free survival rates were 95% and 93%, respectively. Cosmesis was rated by 90% of the patients as excellent or good. 14/113 patients experienced grade III (all caused by planar telangiectasia) and none of the patients grade IV late toxicity of the skin (RTOG/EORTC). A boost dose of 25 Gy resulted in a significantly higher rate of late toxicity (Fisher's exact test, p < 0.01). Conclusions: PDR brachytherapy is safe, effective, and provides good cosmesis. A CLDR breast boost can be replaced by PDR brachytherapy without significant loss of therapeutic ratio. Ziel: Diese Studie diente der Evaluierung von Effektivität, Toxizität und kosmetischen Ergebnissen eines prospektiv applizierten PDR- (pulsed dose-rate-)Brachytherapieboostkonzeptes bei Patienten mit invasivem Mammakarzinom im Stadium I/II/IIIa. Patienten und Methoden: Insgesamt wurden 113 Patienten nach brusterhaltender Therapie (BET) und externer Bestrahlung (Median 50 Gy, Range 46-52) behandelt. Die Boostdosis wurde anhand histopathologischer Tumorcharakteristika graduiert (Tabelle 1): 20-25 Gy: inkomplette Resektion (n = 34), Lymphgefäß- oder Gefäßinvasion (n = 27), "close-margin"-Resektion (n = 41); 15 Gy: T2G3 Stadium (n = 11). Die gepulste Brachytherapie (37 GBq, ¹⁹²Ir-Quelle) wurde nach geometrischer Volumenoptimierung mit 1 Gy/Puls/h durchgeführt. Applikation und Dosisspezifikation erfolgten in Anlehnung an das Pariser System. Ergebnisse: Die Lokalrezidivrate betrug nach einer medianen Nachbeobachtungszeit von 61 Monaten 4,4% (5/113). Das aktuarische lokalrezidivfreie 5- und 8-Jahres-Überleben betrug 95% bzw. 93% (Abbildungen 1 und 2). 90% der Patienten beurteilten ihre kosmetischen Ergebnisse als gut oder exzellent (Tablle 3). Bedingt durch flächige Teleangiektasien im Boostareal entwickelten 14/113 Patienten eine Grad-III-Spättoxizität (0/113 Grad IV) der haut (RTOG/EORTC, Tabelle 2). Eine Boostdosis von 25 Gy resultierte in einer signifikant erhöhten Spättoxizitätsrate (Fishers Exakt-Test, p < 0,01, Abbildung 3). Schlussfolgerung: Die gepulste Brachytherapie ist sicher und effektiv. Die kosmetischen Ergebnisse sind gut. Der interstitielle CLDR-Mammaboost kann durch die PDR-Brachytherapie ohne signifikanten Verlust an therapeutischer Breite ersetzt werden.     

Daytime pulsed dose rate brachytherapy as a new treatment option for previously irradiated patients with recurrent oesophageal cancer

The aim of this study was to evaluate the feasibility, effects, and toxicity of pulsed dose rate (PDR) brachytherapy for re-irradiation of oesophageal carcinoma. A total of 16 patients (median age 67 years) with inoperable recurrences from oesophageal cancer after primary radio-(chemo)-therapy (median 50 Gy) were re-irradiated using PDR brachytherapy ((192)Ir, 37 GBq). Treatment was carried out on an outpatient basis applying a weekly 5 Gy daytime schedule (0.5 Gy pulse(-1) h(-1), total dose 15-20 Gy). The dose was prescribed 10 mm from the mid-dwell position and encompassed the clipped tumour extension with 2 cm margins. The use of clips for delineation of tumour extent and catheter movement during irradiations was evaluated. All 61 PDR treatments were applied safely. The median catheter movement was 5 mm, range 2-12 mm. After a median follow-up of 8 months, three patients had a complete and five a partial remission. Body weight increased in 5 of 16 (31%) and was stable in 4 of 16 (25%) patients, respectively. The median grade 2 (RTOG/EORTC) dysphagia-free survival was 17 months. Seven patients experienced grade 1, five grade 2, and one grade 3 late toxicity. Three patients with uncontrolled locoregional disease showed grade 4 complications (oesophago-tracheal fistulae (n=2), fatal arterial bleeding (n=1). Daytime PDR brachytherapy proved to be feasible and provided effective palliation. Toxicity remains a major problem. Thus, total dose should be restricted to <15 Gy in this palliative situation.     

Late Effects and Cosmetic Results of Conventional Versus Hypofractionated Irradiation in Breast-Conserving Therapy

BACKGROUND AND PURPOSE: Breast irradiation after lumpectomy is an integral component of breast-conserving therapy (BCT). As the prognosis is general good following BCT, late morbidity and cosmesis are important. The present study compares two different radiation schedules with respect to these two endpoints. PATIENTS AND METHODS: 129 breast cancer patients (pT1-2 pN0-1 cM0) were irradiated between 09/1992 and 08/1994 with either a 22-day fractionation schedule (2.5 Gy to 55 Gy, 4x/week, n = 65) or with a conventional fractionation schedule (28 days, 2.0 Gy to 55 Gy, 5x/week, n = 64), both without additional boost. The equivalent dose of 2-Gy fractions (EQD2) was 55 Gy and 62 Gy, respectively. Late toxicity, assessed according to the LENT-SOMA criteria, and cosmetic outcome, graded on a 5-point scale, were evaluated after a median of 86 months (range 72-94 months) in tumor-free breast cancer patients. RESULTS: LENT-SOMA grade 2/3 toxicity (2.5 Gy vs. 2.0 Gy): breast pain (18% vs. 11%; p = 0.3), fibrosis (57% vs. 16%; p < 0.001), telangiectasia (22% vs. 3%; p = 0.002), atrophy (31% vs. 3%; p < 0.001). Medication to breast pain was taken by 8% versus 9% of patients. Cosmesis was very good/good/acceptable in 75% versus 93% (2.5 Gy vs. 2.0 Gy; p = 0.006). CONCLUSION: Late morbidity was significantly frequent and cosmesis was significantly worse after hypofractionated radiotherapy (2.5 Gy to 55 Gy). However, morbidity was not associated with major implications on daily life.     

Electron and High-Dose-Rate Brachytherapy Boost in the Conservative Treatment of Stage I–II Breast Cancer

BACKGROUND AND AIMS: To evaluate the effect of electron and high-dose-rate brachytherapy (HDR BT) boost on local tumor control (LTC), side effects and cosmesis after breast-conserving surgery (BCS) in a prospective randomized study. PATIENTS AND METHODS: 207 women with stage I-II breast cancer who underwent BCS were treated by 50 Gy irradiation to the whole breast and then randomly assigned to receive either a boost to the tumor bed (n = 104) or no further radiotherapy (n = 103). Boost treatments consisted of either 16 Gy electron irradiation (n = 52) or 12-14,25 Gy HDR BT (n = 52). Breast cancer-related events, side effects, and cosmetic results were assessed. RESULTS: At a median follow-up of 5.3 years, the crude rate of local recurrences was 6.7% (7/104) with and 15.5% (16/103) without boost. The 5-year probability of LTC, relapse-free survival (RFS), and cancer-specific survival (CSS) was 92.7% vs. 84.9% (p = 0.049), 76.6% vs. 66.2% (p = 0.044), and 90.4% vs. 82.1% (p = 0.053), respectively. There was no significant difference in LTC between patients treated with electron or HDR BT boost (94.2% vs. 91.4%; p = 0.74). On multivariate analysis, patient age < 40 years (RR: 4.53), positive margin status (RR: 4.17), and high mitotic activity index (RR: 3.60) were found to be significant risk factors for local recurrence. The incidence of grade 2-3 side effects was higher in the boost arm (17.3% vs. 7.8%; p = 0.03). However, the rate of excellent/good cosmetic results was similar for the two arms (85.6% vs 91.3%; p = 0.14). Cosmesis was rated as excellent/good in 88.5% of patients treated with HDR BT and 82.7% of patients with electron boost (p = 0.29). CONCLUSIONS: Boost dose significantly improves LTC and RFS in patients treated with BCS and radiotherapy. In spite of the higher incidence of late side effects in the boost arm, boost dose is strongly recommended for patients at high risk for local recurrence. Positive or close margin status, high mitotic activity index, and young patient age should be viewed as absolute indications for tumor bed boost. LTC and cosmesis are excellent and similar to patients boosted with either HDR BT or electrons.     

Interstitial brachytherapy alone after breast conserving surgery: interim results of a German-Austrian multicenter phase II trial

PURPOSE: To evaluate the value of interstitial brachytherapy (iBT) alone in the treatment of low-risk breast cancer patients with regard to local control, side effects, and cosmesis. METHODS AND MATERIALS: From November 2000 to January 2004, 176 patients with low-risk breast cancer were treated with iBT only. Patients were eligible for entering the study if: the tumor size was <3 cm; resection margins were clear by at least 2 mm; there were no lymph node metastases or only one micrometastasis (pNo, pNmi); age was >35 years; steroid hormone receptor was positive; and histologic grade was 1 or 2. Seventy-five percent of patients received pulsed-dose-rate brachytherapy (D(ref) = 50 Gy); 25% of patients received high-dose-rate brachytherapy (D(ref) = 32.0 Gy). An interim analysis is presented for all patients after an interim follow-up of 12 months, and for half the patient population with an interim follow-up of 21 months. RESULTS: All patients remained disease-free on the date of analysis. A perioperative complication breast infection was recorded for 1/176 (0.6%) patients. Late toxicity i.e., hypersensation, hyperpigmentation, fibrosis, or teleangiectasia was observed in 1-12% of all patients. Grade I Fibrosis was registered in 7.6% (13/172) and grade II in 7.0% (12/172) of evaluable patients. Similarly, grade I teleangiectasia was observed in 4.7% (8/172), grade II in 0.6% (1/172), and grade III also in 0.6% (1/172) of evaluable patients. Excellent or good cosmetic results have been observed in 92-95% of patients. CONCLUSIONS: Brachytherapy as monotherapy in low-risk breast cancer patients after breast-conserving surgery is an effective, precise treatment modality without perioperative morbidity, low acute, mild late toxicity, and yields good to excellent cosmetic results.     

Brachytherapy focal dose escalation using ultrasound based tissue characterization by patients with non-metastatic prostate cancer: Five-year results from single-center phase 2 trial

PURPOSEThis prospective trial investigates side effects and efficacy of focal dose escalation with brachytherapy for patients with prostate cancer.METHODS AND MATERIALSIn the Phase II, monocentric prospective trial 101 patients with low-/intermediate- and high-risk prostate cancer were enrolled between 2011 and 2013. Patients received either PDR-/HDR-brachytherapy alone with 86–90 Gy (EQD2, α/β = 3 Gy) or PDR-/HDR-brachytherapy as boost after external beam radiation therapy up to a total dose of 91–96 Gy (EQD2, α/β = 3 Gy). Taking place brachytherapy all patients received the simultaneous integrated focal boost to the intra-prostatic tumor lesions visible in computer-aided ultrasonography (HistoScanning?) - up to a total dose of 108–119 Gy (EQD2, α/β = 3 Gy). The primary endpoint was toxicity. Secondary endpoints were cumulative freedom from local recurrence, PSA-free survival, distant metastases-free survival, and overall survival. This trial is registered with ClinicalTrials.gov, number NCT01409876.ResultsMedian follow-up was 65 months. Late toxicity was generally low with only four patients scoring urinary grade 3 toxicity (4/101, 4%). Occurrence of any grade of late rectal toxicities was very low. We did not register any grade ≥2 of late rectal toxicities. The cumulative 5 years local recurrence rate (LRR) for all patients was 1%. Five years- biochemical disease-free survival estimates according Kaplan-Meier were 98,1% and 81,3% for low-/intermediate-risk and high-risk patients, respectively. Five years metastases-free survival estimates according Kaplan-Meier were 98,0% and 83,3% for all patients, low-/intermediate-risk and high-risk patients, respectively.ConclusionsThe 5 years-results from this Phase II Trial show that focal dose escalation with computer-aided ultrasonography and brachytherapy for patients with non-metastatic prostate cancer is safe and effective.     

Feasibility and Early Results of Interstitial Intensity-Modulated HDR/PDR Brachytherapy (IMBT) with/without Complementary External-Beam Radiotherapy and Extended Surgery in Recurrent Pelvic Colorectal Cancer

BACKGROUND: A new multimodality treatment concept consisting of extended resection and postoperative fractionated intensity-modulated interstitial brachytherapy (IMBT) was introduced for pelvic recurrence of colorectal carcinoma. PATIENTS AND METHODS: 46 patients received extended resection and single plastic tubes were sutured directly onto the tumor bed. IMBT was started within 2 weeks postoperatively with a median dose of 24.5 Gy (5-35 Gy). Patients were treated either with high-dose-rate brachytherapy (HDR; n = 23) or with pulsed-dose-rate brachytherapy (PDR; n = 23). 25 patients received complementary 45-Gy external-beam irradiation (EBRT) to the pelvic region after explanting the plastic tubes. RESULTS: Median follow-up was 20.6 months (7-107 months) and mean patient survival 25.7 +/- 25.8 months (median 17, range 1-107 months). After 5 years overall survival, disease-free survival and local control rate were 23%, 20% and 33%, significantly influenced by the resectional state. There was a trend in favor of PDR compared to HDR, which reached statistical significance in patients who had not received additional EBRT. CONCLUSION: The combination of extended surgery and postoperative interstitial IMBT is feasible and offers effective interdisciplinary treatment of recurrent colorectal cancer. In this small and inhomogeneous cohort of patients PDR seems to be more effective than HDR, particularly when application of complementary EBRT is not possible. None of the patients who required resection of distant metastasis survived > 2 years in this study.     

Long-term results of pulsed irradiation of skin metastases from breast cancer. Effectiveness and sequelae.

PURPOSE: The concept of pulsed brachytherapy suggested by Brenner and Hall requires an unusual fractionation scheme. Effectiveness and sequelae of this new irradiation method were observed in patients with disseminated cutaneous metastases of breast cancer. PATIENTS AND METHODS: A flexible, reusable skin mold (weight 110 g) was developed for use with a pulsed dose rate (PDR) afterloader. An array of 18 parallel catheters (2 mm diameter) at equal distances of 10 or 12 mm was constructed by fixation of the catheters in a plastic wire mesh. The array is sewn between 2 foam rubber slabs of 5 mm thickness to provide a defined constant distance to the skin. Irradiations are possible up to a maximum field size of 20 x 23.5 cm using a nominal 37 GBq Ir-192 source. Pulses of 1 Gy reference dose at the skin surface are applied at a rate of 1 pulse every 1.2 hours (0.8 Gy per hour). The dose distribution is geometrically optimized to provide a homogeneous skin dose (100% +/- 10%). The 80% dose level lies at 5 mm below the skin surface. Between April 1994 and December 1997, 52 patients suffering from cutaneous metastases at the thoracic wall were treated with 54 fields and total doses of 38 to 50 Gy (median 42 Gy) applying 2 PDR courses with a pause of 4 to 5 weeks. RESULTS: Forty-six patients (48 fields) were eligible for evaluation in June 1998. The median follow-up was 16 months (range 7.1 to 46.2 months). Local control was achieved in 40 out of 48 fields (83%) or 41 of 46 patients (89%), respectively. Moist desquamation occurred in 52% of the patients. Late reactions were judged after a minimum follow-up of 6 months. Thirty-two fields had been previously irradiated with external beam therapy to doses of 40 to 60 Gy. Regardless of whether the skin was preirradiated or not all patients surviving long enough developed telangiectasia within 2 years after PDR irradiation. In preirradiated patients (n = 32) skin contractures and/or skin necrosis occurred in 12% each. In newly irradiated patients (n = 14) no contractures or skin necrosis were observed. CONCLUSIONS: Pulsed brachytherapy is an effective and time-sparing method for the treatment of cutaneous metastases from breast cancer. Skin reactions are comparable to the sequelae of orthovoltage therapy. Two sessions of approximately 20 Gy PDR were tolerated on preirradiated skin without severe sequelae.     

Preliminary Report of Pulsed Dose Rate Brachytherapy in Head-and-Neck Cancer

PURPOSE: To assess the feasibility and acute/delayed toxicity of pulsed-dose-rate brachytherapy (PDR BT) in head-and-neck tumors. PATIENTS AND METHODS: 45 head and neck cancer patients underwent interstitial or contact PDR BT at a dose of 10.2-70 Gy (median, 70 Gy) and 0.6 or 1.0 Gy/pulse/h. 42 patients were administered BT as part of their curative treatment; 32 of them had sole BT. Three reirradiated patients with recurrent tumor had palliative BT. RESULTS: PDR BT was well tolerated. Intense bleeding was the only complication associated with catheter removal from the tongue and bucca. 44 patients who completed BT experienced acute mucositis. Grade 3 toxicity of skin and oral mucosa occurred in three (6.8%) and six patients (13.6%), respectively. At a median follow-up of 22 months (range, 2-67 months), late serious toxicity (grade 4, for soft tissue and bone) was seen in seven patients (15.9%). Among the parameters analyzed, only dental care performed before BT had a significant impact on mucosal side effects. Acute severe mucositis was observed in 23% of patients without dental care compared to 0% of those with dental care (p=0.044). Late severe mucositis occurred in 17.7% and 26.9% of the respective patients (p=0.035), overall in 23%. The larger the volume encompassed by the reference isodose, the more late (p=0.004) mucosal reactions were observed. CONCLUSION: PDR BT continued over a few days is a feasible and safe approach in head-and-neck tumors; however, it is accompanied by some toxicity. Dental care should precede isotope application.     

Locally recurrent breast cancer: pulse dose rate brachytherapy for repeat irradiation following lumpectomy-- a second chance to preserve the breast

PURPOSE: To perform and assess the effectiveness of local excision of recurrent tumor followed by postoperative pulse dose rate (PDR) brachytherapy. MATERIALS AND METHODS: From 1994 to 2000, 17 patients who had small recurrent breast carcinomas after initially undergoing breast-conserving therapy (BCT), which included postoperative radiation therapy, were treated with local tumor excision and PDR brachytherapy. Recurrences occurred at a median time of 50 months (range, 11-208 months) after primary treatment. Eight patients underwent a combination of PDR brachytherapy (total dose range, 12.5-28.0 Gy) and external-beam radiation therapy (EBT) (total dose range, 12-30 Gy). Nine patients underwent radiation therapy with 40.2-50.0-Gy PDR brachytherapy only. The prescribed radiation dose was 0.5-1.0 Gy per pulse. Patients were examined for local tumor control and treatment-related side effects. RESULTS: Twelve of 17 patients had no local tumor at a median follow-up time of 59 months (range, 20-84 months); two of these patients showed signs of having distant disease. One patient died after a cerebral stroke without evidence of tumor. Four women treated with combined EBT and brachytherapy had secondary local tumor recurrences 4, 8, 8, and 11 months after therapy and had to undergo mastectomy. Despite having undergone radiation therapy previously, patients had side effects limited to moderate (grade 1-2) fibrosis. CONCLUSION: Local tumor excision combined with PDR brachytherapy for small local-regional tumor recurrences after primary BCT is feasible and well tolerated and might obviate mastectomy. Preliminary experiences are encouraging. Further studies are required for appropriate patient selection.     

Esophageal Cancer

PURPOSE: To present the results of a prospective phase II study in esophageal carcinoma. PATIENTS AND METHODS: Patients received single doses of 1.8 Gy up to 27 Gy, then concomitant boost to a total of 50.4 Gy (PTV2 [planning target volume], single dose 1.8 Gy) and 64.8 Gy (PTV1, single dose 1.2 Gy in the morning and 1.8 Gy in the afternoon) concurrently with 800 mg/m(2)/d 5-fluorouracil and 20 mg/m(2)/d cisplatin (weeks 1 and 5). High-dose-rate brachytherapy (2-3 x 6 Gy) on Fridays of weeks 4-6 used a customized applicator facilitating central placement and circumferential dose homogeneity. RESULTS: 50 patients with squamous cell carcinoma (90%) or adenocarcinoma and mostly advanced tumor stage were treated (82% T3/T4 and 70% N1). Median overall survival (median OS 16 months; 1-year-OS 61%; 2-year OS 29%) was significantly longer for patients without nodal disease (35 vs. 11 months; p = 0.01). Hematotoxicity was grade 3 in 11/50, and grade 4 in 1/50 patients. Four percent of higher-grade nausea or vomiting occurred. Esophageal late toxicity was grade 3 in 9/50 patients, and grade 4 in 2/50 patients. CONCLUSION: Survival was excellent especially for patients without nodal disease in this dose-intensified schedule with acceptable tolerability.     

Experiences with a New High-Dose-Rate Brachytherapy (HDR-BT) Boost Technique for T3b Prostate Cancer

PURPOSE: Experiences with a new high-dose-rate brachytherapy (HDR-BT) boost technique in 41 patients with stage T3b prostate cancer are presented. PATIENTS AND METHODS: The patients received 18 Gy of HDR-BT (9 Gy on days 1 + 8) plus 50.4 Gy of EBRT. 20 patients (group A) had BT applicators placed into the prostate alone resulting in 18 Gy to prostate and 0 Gy (tip) to 12 Gy (base) to seminal vesicles (SV). The cumulative EQD2 (equivalent dose in 2-Gy fractions, alpha/beta 1.5 Gy) to the SV was 47.5-73.3 Gy. 21 patients (group B) had BT applicators placed into both prostate and SV resulting in 18 Gy to prostate and to > 80% (but not 100%) of the SV (cumulative EQD2 81.5-101.5 Gy). Both groups were compared for acute and late toxicity and for biochemical relapse-free survival (bRFS). RESULTS: The 3-year bRFS was 57% for group A and 79% for group B patients (p = 0.29). A grade 3 acute toxicity (CTC 2.0) was not observed. Grade 2 acute toxicity (proctitis, cystitis, skin toxicity) was comparable in both groups. A grade 3 late toxicity did not occur. Impotence rates were 35% in group A and 24% in group B, respectively (p = 0.73). CONCLUSION: The new HDR-BT technique (group B) was associated only with minor acute and late toxicity and appears to result in better bRFS than the conventional HDR-BT technique (group A). The results must be confirmed in a prospective trial.     

Role of Interstitial PDR Brachytherapy in the Treatment of Oral and Oropharyngeal Cancer

PURPOSE: To evaluate the role of pulsed-dose-rate interstitial brachytherapy (PDR IBT) in patients with head-and-neck malignancies. PATIENTS AND METHODS: From October 1997 to December 2003, 236 patients underwent PDR IBT for head-and-neck cancer at the authors' department. 192 patients received brachytherapy as part of their curative treatment regimen after minimal non-mutilating surgery, 44 patients were treated with irradiation alone. 144 patients had sole IBT (median D(REF) = 56 Gy), in 92 patients IBT procedures (median D(REF) = 24 Gy) were performed in combination with external irradiation. The pulses (0.4-0.7 Gy/h) were delivered 24 h a day with a time interval of 1 h between two pulses. The analysis of tumor control, survival and treatment-related toxicity was performed after a median follow-up of 26 months (6-75 months). RESULTS: At the time of analysis permanent local tumor control was registered in 208 of 236 patients (88%). At 5 years overall survival and local recurrence-free survival of the entire group were 82-73% and 93-83% for T1/2, and 56% and 83% for T3/4, respectively. Soft-tissue necrosis was seen in 23/236 patients (9.7%) and bone necrosis in 17/236 patients (7.2%). No other serious side effects were observed. CONCLUSION: PDR IBT with 0.4-0.7 Gy/h and 1 h between pulses is safe and effective. These results confirm that PDR IBT of head-and-neck cancer is comparable with low-dose-rate (LDR) brachytherapy - equally effective and less toxic.     

Differential effects of CLDR and PDR brachytherapy on cell cycle progression in a syngeneic rat prostate tumour model

PURPOSE: The study consisted of two treatment arms comparing the effects of CLDR (continuous low dose rate) and PDR (pulsed dose rate) brachytherapy on cell cycle progression in a radioresistant rat prostate tumour model. MATERIALS AND METHODS: Interstitial PDR and CLDR brachytherapy (both 192-Ir, 0.75 Gy/h) were administered to Dunning prostate R3327-AT1 carcinomas transplanted subcutaneously into the thigh of Copenhagen rats. Increasing doses of up to 20 as well as up to 40 Gy were applied. Cell cycle distributions of the aneuploid tumour cell subpopulations were determined at 4 h (3 Gy), 24 h (18 Gy), 48 h (20 and 36 Gy), as well as during the subsequent redistribution period (20 and 40 Gy) at 72, 96, and 120 h. Tumours either implemented with an empty tubing system (n=5) or under undisturbed growth (n=5) served as controls. Three animals were irradiated per time point and exposure condition. At least two flow cytometrical analyses were carried out per animal. RESULTS: The aneuploid cells possessed a constant DNA-Index of 1.9+/-0.06. In contrast to sham-treated controls, the aneuploid cell fraction with G2/M DNA content was significantly increased (p<0.05) after initiation of both, CLDR and PDR brachytherapy. However, CLDR resulted in an earlier accumulation of tumour cells in G2/M (24 h: 28% CLDR vs. 19% PDR, p<0.05) with a concomitant reduction of cells in G1, whereas PDR yielded delayed, but then more pronounced cell cycle changes, particularly expressed during the redistribution period after both 20 and 40 Gy. CONCLUSION: CLDR and PDR brachytherapy showed differential effects on cell cycle progression. The induction of a significantly earlier but also less persistent G2/M cell cycle arrest after CLDR compared to PDR brachytherapy implies that a substantially higher fraction of tumour cells are irradiated in G2/M after CLDR.     

High-Dose-Rate (HDR) or Pulsed-Dose-Rate (PDR) Perioperative Interstitial Intensity-Modulated Brachytherapy (IMBT) for Local Recurrences of Previously Irradiated Breast or Thoracic Wall Following Breast Cancer

PURPOSE: In patients receiving salvage high-dose-rate (HDR) or pulsed-dose-rate (PDR) brachytherapy for a local recurrence on the chest wall or in the previously treated breast, clinical outcome and benefit were investigated. All patients had previously been treated with full-dose adjuvant external-beam irradiation (EBRT). Disease-free interval after salvage treatment, local tumor control and side effects were analyzed retrospectively. PATIENTS AND METHODS: Between 1996 and 2002, a total of 32 consecutive patients were treated. 13 patients initially treated with mastectomy and postoperative irradiation and 19 patients initially treated with breast-conserving surgery and postoperative irradiation developed a local recurrence. The mean dose of previous radiation therapy was 58 Gy (range, 42-64 Gy), applied by conventional fractionation. After implantation +/- surgery of recurrent disease and CT-based 3-D planning, 15 patients were irradiated with HDR-IMBT (intensity-modulated brachytherapy) with a mean dose of 28 Gy (range, 10-30 Gy, 2 x 2.5 Gy/day at 6-h daily interfraction interval) and 17 patients received PDR-IMBT with a mean dose 30 Gy (range, 10-45 Gy, 5 x 1 Gy/day at 2-h pulse intervals). Four patients underwent additional EBRT using a dose of 24-40 Gy electrons. Treatment was performed only on working days. RESULTS: After a mean post-implant follow-up of 19 months (range, 1-83 months), no signs of local recurrence were observed in 20 of the 32 patients. In twelve patients, local recurrence occurred after a mean follow-up of 13 months (range, 1-78 months). 20 of the 32 patients experienced an additional systemic progress. In one patient, an EORTC/RTOG grade 3 side effect (ulceration of the skin) was described, which was followed by a local recurrence 12 months posttherapeutically. CONCLUSION: Perioperative interstitial HDR/PDR-IMBT of localized breast or thoracic wall recurrences following previous full-dose EBRT appears to be a meaningful salvage treatment with acceptable toxicity.     

Brachytherapy-based partial breast irradiation is associated with low rates of complications and excellent cosmesis

BackgroundRecent retrospective, claims-based analyses have suggested a potential increased rate of toxicities associated with brachytherapy-based accelerated partial breast irradiation (APBI). The purpose of this analysis was to examine cosmesis and toxicity data from the prospective American Society of Breast Surgeons (ASBS) breast brachytherapy registry trial to compare to the findings from the claims analyses.MethodsThe ASBS breast brachytherapy registry is a prospective nonblinded multi-institutional registry trial. Patients with Stage 0–II breast cancer undergoing breast conserving therapy were eligible. A total of 1665 patients were enrolled and 1449 treated between 2002 and 2004 with a median followup of 63 months. All patients were treated with the MammoSite (Hologic, Inc.) single-lumen device to deliver adjuvant APBI (34 Gy in 3.4 Gy fractions).ResultsThe rate of excellent/good cosmesis was 90.6% at 84 months. The rate of a complication (symptomatic seroma, infection, fat necrosis, telangiectasias) at 1 year/any time point was 24.2%/38.5%, whereas the rate of noninfectious complications at 1 year/any time point was 14.8%/28.9%. The rate of symptomatic seroma, fat necrosis, infection, and telangiectasia at any time was 13.4%, 2.5%, 9.6%, and 13.0%, respectively.ConclusionsThe final toxicity analysis from ASBS breast brachytherapy registry trial confirms the previously noted excellent cosmesis and toxicity profiles and fails to confirm retrospective claims analyses that have suggested higher rates of toxicity for brachytherapy-based APBI.     

Accelerated Partial-Breast Irradiation with Interstitial Implants

PURPOSE: To describe relative skin dose estimations and their impact on cosmetic outcome in interstitial multicatheter accelerated partial-breast irradiation (APBI). PATIENTS AND METHODS: Between April 2001 and January 2005, 105 consecutive patients with early breast cancer were recruited in Erlangen, Germany, for this substudy of the German-Austrian APBI phase II trial. 51% (54/105) received pulsed-dose-rate (PDR), and 49% (51/105) high-dose-rate (HDR) brachytherapy. Prescribed reference dose for HDR brachytherapy was 32 Gy in eight fractions of 4 Gy, twice daily. Prescribed reference dose in PDR brachytherapy was 49.8 Gy in 83 consecutive fractions of 0.6 Gy every hour. Total treatment time was 3-4 days. With a wire cross on the skin surface during the brachytherapy-planning procedure the minimal, mean and maximal relative skin doses (SD(min%), SD(max%), SD(mean%)) were recorded. Endpoint of this evaluation was the cosmetic outcome in relation to the relative skin doses. RESULTS: Median follow-up time was 38 months (range, 19-65 months). Cosmetic results for all patients were excellent in 57% (60/105), good in 36% (38/105), and fair in 7% (7/105). The SD(min%) (27.0% vs. 31.7%; p = 0.032), SD(mean%) (34.2% vs. 38.1%; p = 0.008), and SD(max%) (38.2% vs. 46.4%; p = 0.003) were significantly lower for patients with excellent cosmetic outcome compared to patients with a suboptimal outcome. SD(mean%) (37.6% vs. 34.2%; p = 0.026) and SD(max%) (45.4% vs. 38.2%; p = 0.008) were significantly higher for patients with good cosmetic outcome compared with the patients with excellent results. CONCLUSION: The appraisal of skin doses has been shown to be relevant to the achievement of excellent cosmetic outcome. Further investigations are necessary, especially on the basis of CT-based brachytherapy planning, to further improve the treatment results of multicatheter APBI.     

Electron and High-Dose-Rate Brachytherapy Boost in the Conservative Treatment of Stage I-II Breast Cancer First Results of the Randomized Budapest Boost Trial

Background and Aims: To evaluate the effect of electron and high-dose-rate brachytherapy (HDR BT) boost on local tumor control (LTC), side effects and cosmesis after breast-conserving surgery (BCS) in a prospective randomized study. Patients and Methods: 207 women with stage I-II breast cancer who underwent BCS were treated by 50 Gy irradiation to the whole breast and then randomly assigned to receive either a boost to the tumor bed (n = 104) or no further radiotherapy (n = 103). Boost treatments consisted of either 16 Gy electron irradiation (n = 52) or 12-14,25 Gy HDR BT (n = 52). Breast cancer-related events, side effects, and cosmetic results were assessed. Results: At a median follow-up of 5.3 years, the crude rate of local recurrences was 6.7% (7/104) with and 15.5% (16/103) without boost. The 5-year probability of LTC, relapse-free survival (RFS), and cancer-specific survival (CSS) was 92.7% vs. 84.9% (p = 0.049), 76.6% vs. 66.2% (p = 0.044), and 90.4% vs. 82.1% (p = 0.053), respectively. There was no significant difference in LTC between patients treated with electron or HDR BT boost (94.2% vs. 91.4%; p = 0.74). On multivariate analysis, patient age < 40 years (RR: 4.53), positive margin status (RR: 4.17), and high mitotic activity index (RR: 3.60) were found to be significant risk factors for local recurrence. The incidence of grade 2-3 side effects was higher in the boost arm (17.3% vs. 7.8%; p = 0.03). However, the rate of excellent/good cosmetic results was similar for the two arms (85.6% vs 91.3%; p = 0.14). Cosmesis was rated as excellent/good in 88.5% of patients treated with HDR BT and 82.7% of patients with electron boost (p = 0.29). Conclusions: Boost dose significantly improves LTC and RFS in patients treated with BCS and radiotherapy. In spite of the higher incidence of late side effects in the boost arm, boost dose is strongly recommended for patients at high risk for local recurrence. Positive or close margin status, high mitotic activity index, and young patient age should be viewed as absolute indications for tumor bed boost. LTC and cosmesis are excellent and similar to patients boosted with either HDR BT or electrons. Hintergrund und Ziel: In einer prospektiv randomisierten Studie werden die Effekte eines Elektronenboosts und eines High-Dose-Rate-Brachytherapie-(HDR-BT-)Boosts bezüglich lokaler Tumorkontrolle (LTC), Nebenwirkungen und kosmetischer Ergebnisse nach brusterhaltender Operation (BCS) evaluiert. Patienten und Methodik: 207 Patientinnen mit Brustkarzinomen im Stadium I-II wurden einer BCS zugeführt. Postoperativ erfolgte eine perkutane Radiatio der gesamten Brust bis 50 Gy. Daran schloss sich willkürlich entweder eine Boostbestrahlung des Tumorbetts (n = 104) oder keine weitere Radiatio (n = 103) an. Die Boostbestrahlung erfolgte perkutan mit 16 Gy Elektronen (n = 52) oder in Form einer HDR-BT mit 12-14,25 By (n = 52). Untersucht wurden LTC, Nebenwirkungen und kosmetische Ergebnisse. Ergebnisse: Die mediane Nachbeobachtungszeit betrug 5,3 Jahre. Die Lokalrezidivrate lag mit Boostbestrahlung bei 6,7% (7/104), ohne Boost bei 15,5% (16/103). Die 5-Jahres-Überlebensrate für LTC, für die rezidivfreie Überlebenszeit (RFS) und für die krebsspezifische Überlebenszeit (CSS) betrugen 92,7% vs. 84,9% (p = 0,049), 76,6% vs. 66,2% (p = 0,044) und 90,4% vs. 82,1% (p = 0,053). Bezüglich der LTC bestand kein signifikanter Unterschied zwischen Patienten, die mit einem Elektronen- oder HDR-BT-Boost behandelt wurden (94,2% vs. 91,4$; p = 0,74). Die multivariate Analyse zeigte, dass Faktoren wie Patientenalter > 40 Jahre (RR: 4,53), positive Resektionsränder (RR: 4,17) und ein hoher Mitoseaktivitätsindex (RR: 3.60) das Risiko eines lokalen Rezidivs signifikant erhöhen. Die Inzidenz von Nebenwirkungen Grad 2-3 war im Boost-Arm höher (17,3% vs. 7,8%; p = 0,03). Allerdings waren die sehr guten kosmetischen Ergebnisse in beiden Armen gleich (85,6% bs. 91,3%, p = 0,14). Sehr gute kosmetische Ergebnisse wurden bei 88,5% der Patientinnen mit HDR-BT-Boost und 82,7% der Patientinnen mit Elektronenboost erreicht (p = 0,29). Schlussfolgerungen: Die Boost-Dosis verbessert signifikant LTC und RFS bei Patientinnen, die einer BCS und anschließender Radiatio zugeführt wurden. Obwohl eine höhere Inzidenz an Spätnebenwirkungen im Boost-Arm gefunden wurde, wird eine Boost-Dosis für Patientinnen mit hohem Risiko für die Entwicklung eines Lokalrezidivs empfohlen. Unserer Meinung nach ist bei Faktoren wie positive Schnittränder, schmaler Sicherheitssaum, hoher Mitoseaktivitätsindex und niedriges Patientenalter, die absolute Indikation zur Boost-Bestrahlung des Tumorbetts gegeben. LTC und die kosmetischen Ergebnisse sind sehr gut und unterscheiden sich nicht in Bezug auf Elektronenboost oder HDR-BT-Boost.     

Template-based high-dose-rate interstitial brachytherapy in gynecologic cancers: A single institutional experience

PurposeTo report the outcome and toxicities of radical external beam radiotherapy (EBRT) and template-based high-dose-rate interstitial brachytherapy (ISBT) in patients diagnosed with cervical cancer undergoing inadvertent surgery, vault cancers, and vaginal cancers at our institution.Methods and MaterialsBetween January 2000 and December 2008, 113 patients (37 patients of cervical cancer post-inadvertent surgery, 57 patients with vault cancers, and 19 patients with primary vaginal cancers) were treated with Martinez Universal Perineal Interstitial Template brachytherapy boost after EBRT. The median EBRT dose was 50 Gy, median ISBT dose was 20 Gy, whereas median total dose was 73 Gy equivalent dose at 2 Gy per fraction in all three groups.ResultsMedian followup of surviving patients for the whole group was 43 months (interquartile range, 19–67 months). The 3-year actuarial disease-free survival and overall survival for three groups was 61%, 61%, 59% and 64%, 64%, and 56%, respectively. Grade III/IV rectal toxicity was seen in 11 (10%) patients, bladder toxicity in 5 (4.5%) patients, whereas 7 (6%) patients developed Grade III small bowel toxicity. Residual disease at brachytherapy had significant impact on DFS and OS. Other factors such as age, disease volume, parametrial extension, and vaginal extension did not impact the survivals.ConclusionsMartinez Universal Perineal Interstitial Template–based high-dose-rate ISBT boost in gynecologic cancer results in a reasonable outcome in terms of survivals with acceptable late toxicities. The use of template-based ISBT is associated with a definite learning curve.