High dose rate (HDR) endobronchial brachytherapy is a
palliative treatment for symptomatic airway obstruction by malignant tumours. We report a novel use of HDR brachytherapy for treating non-malignant bronchial obstruction. The patient had a metal stent placed in a reconstructed airway after a bronchial tear to ensure patency. Granulation tissue formation in and around the stent caused
symptomatic occlusion of the airway, necessitating multiple laser
applications. A single treatment of HDR brachytherapy (1000 cGy) was
delivered following laser therapy. The patient remains well 15 months
after treatment with no evidence of recurrent granulation tissue
formation on bronchoscopy. HDR brachytherapy is an effective treatment
for non-malignant airway obstruction.
The literature supporting high-dose rate brachytherapy (HDR) in the treatment of cervical carcinoma derives primarily from retrospective series. However, controversy still persists regarding the efficacy and safety of HDR brachytherapy compared to low-dose rate (LDR) brachytherapy, in particular, due to inadequate tumor coverage for stage III patients. Whether LDR or HDR brachytherapy produces better results for these patients in terms of survival rate, local control rate and the treatment complications remain controversial.
A meta-analysis of RCT was performed comparing LDR to HDR brachytherapy for cervix cancer treated for radiotherapy alone. The MEDLINE, EMBASE, CANCERLIT and Cochrane Library databases, as well as abstracts published in the annual proceedings were systematically searched. We assessed methodological quality for each outcome by grading the quality of evidence using the Grading of Recommendations Assessment, Development and Evaluation (GRADE) methodology. We used "recommend" for strong recommendations, and "suggest" for weak recommendations.
Pooled results from five randomized trials (2,065 patients) of HDR brachytherapy in cervix cancer showed no significant increase of mortality (p = 0.52), local recurrence (p = 0.68), or late complications (rectal; p = 0.7, bladder; p = 0.95 or small intestine; p = 0.06) rates as compared to LDR brachytherapy. In the subgroup analysis no difference was observed for overall mortality and local recurrence in patients with clinical stages I, II and III. The quality of evidence was low for mortality and local recurrence in patients with clinical stage I, and moderate for other clinical stages.
Our meta-analysis shows that there are no differences between HDR and LDR for overall survival, local recurrence and late complications for clinical stages I, II and III. By means of the GRADE system, we recommend the use of HDR for all clinical stages of cervix cancer.
To investigate the efficacy and safety of accelerated partial breast irradiation (APBI) via high-dose-rate (HDR) multicatheter interstitial brachytherapy for early-stage breast cancer.
Between 2002 and 2006, 48 prospectively selected patients with early-stage breast cancer received APBI using multicatheter brachytherapy following breast-conserving surgery. Their median age was 52 years (range 36-78). A median of 34 Gy (range 30-34) in 10 fractions given twice daily within 5 days was delivered to the tumor bed plus a 1-2 cm margin. Most (92%) patients received adjuvant systemic treatments. The median follow-up was 53 months (range 36-95). Actuarial local control rate was estimated from surgery using Kaplan-Meier method.
Local recurrence occurred in two patients. Both were true recurrence/marginal miss and developed in patients with close (< 0.2 cm) surgical margin after 33 and 40 months. The 5-year actuarial local recurrence rate was 4.6%. No regional or distant relapse and death has occurred to date. Late Grade 1 or 2 late skin and subcutaneous toxicity was seen in 11 (22.9%) and 26 (54.2%) patients, respectively. The volumes receiving 100% and 150% of the prescribed dose were significantly higher in the patients with late subcutaneous toxicity (p = 0.018 and 0.034, respectively). Cosmesis was excellent to good in 89.6%.
APBI using HDR multicatheter brachytherapy yielded local control, toxicity, and cosmesis comparable to those of conventional whole breast irradiation for select early-stage breast cancer. Patients with close resection margins may be ineligible for APBI.
Brachytherapy results in better dose distribution compared with other treatments because of steep dose reduction in the surrounding normal tissues. Excellent local control rates and acceptable side effects have been demonstrated with brachytherapy as a sole treatment modality, a postoperative method, and a method of reirradiation. Low-dose-rate (LDR) brachytherapy has been employed worldwide for its superior outcome. With the advent of technology, high-dose-rate (HDR) brachytherapy has enabled health care providers to avoid radiation exposure. This therapy has been used for treating many types of cancer such as gynecological cancer, breast cancer, and prostate cancer. However, LDR and pulsed-dose-rate interstitial brachytherapies have been mainstays for head and neck cancer. HDR brachytherapy has not become widely used in the radiotherapy community for treating head and neck cancer because of lack of experience and biological concerns. On the other hand, because HDR brachytherapy is less time-consuming, treatment can occasionally be administered on an outpatient basis. For the convenience and safety of patients and medical staff, HDR brachytherapy should be explored. To enhance the role of this therapy in treatment of head and neck lesions, we have reviewed its outcomes with oral cancer, including Phase I/II to Phase III studies, evaluating this technique in terms of safety and efficacy. In particular, our studies have shown that superficial tumors can be treated using a non-invasive mold technique on an outpatient basis without adverse reactions. The next generation of image-guided brachytherapy using HDR has been discussed. In conclusion, although concrete evidence is yet to be produced with a sophisticated study in a reproducible manner, HDR brachytherapy remains an important option for treatment of oral cancer.
brachytherapy; oral cancer; high dose rate
Surgery is the major therapeutic method in soft tissue sarcomas of the extremity (E-STS). Treatment of large high-grade tumours, which resection cannot be performed with a wide safe margin, should include complementary radiation and/or chemo-therapy. Hopefully, the use of adjuvant brachytherapy will improve the prognosis of E-STS.
After a long process of diagnosing a tumour in the medial compartment of the thigh, a 65-year-old woman with diagnosed synovial sarcoma underwent a surgery. Compartment resection was performed and the tumour was removed with a 10 mm safety margin of healthy tissue. Adjuvant brachytherapy was delivered with 192Ir (MicroSelectron, Nucletron Electa Group, Stockholm, Sweden®) with 10 Ci of nominal activity to a dose of 55 Gy in 16 days because of large tumour size (99 × 78 × 73 mm) and its proximity to the neurovascular bundle. No complications were reported. The patient was discharged from the hospital on the 28th day after the surgery. The wound healed without any complications and the outpatient follow-up is being continued.
Adjuvant brachytherapy is rarely used after surgical treatment due to its limited accessibility in hospitals with surgical and orthopaedic departments. There are numerous publications proving positive influence of brachytherapy on local control and decreased number of recurrences. The recurrence-free survival time also increased significantly, however no direct impact on the number of distant metastases was found. Treatment is well tolerated and short. The complication rate varies between centres from 5 to 30%. The most common adverse effects include: peripheral neuropathy, skin necrosis and osteonecrosis of the long bones.
Treatment of large soft tissue sarcomas of the extremity (E-STS) should include combination of surgical intervention and external beam radiotherapy or brachytherapy. Adjuvant brachytherapy improves local control rate up to 78%, is well tolerated and rarely causes complications. We couldn't determine which type of adjuvant radiation therapy is more effective.
soft tissue sarcoma; brachytherapy; compartment surgery
This report presents the 2011 update to the American Brachytherapy Society (ABS) high-dose-rate (HDR) brachytherapy guidelines for locally advanced cervical cancer.
Members of the American Brachytherapy Society (ABS) with expertise in cervical cancer brachytherapy formulated updated guidelines for HDR brachytherapy using tandem and ring, ovoids, cylinder or interstitial applicators for locally advanced cervical cancer were revised based on medical evidence in the literature and input of clinical experts in gynecologic brachytherapy.
The Cervical Cancer Committee for Guideline Development affirms the essential curative role of tandem-based brachytherapy in the management of locally advanced cervical cancer. Proper applicator selection, insertion, and imaging are fundamental aspects of the procedure. Three-dimensional imaging with magnetic resonance or computed tomography or radiographic imaging may be used for treatment planning. Dosimetry must be performed after each insertion prior to treatment delivery. Applicator placement, dose specification and dose fractionation must be documented, quality assurance measures must be performed, and follow-up information must be obtained. A variety of dose/fractionation schedules and methods for integrating brachytherapy with external-beam radiation exist. The recommended tumor dose in 2 Gray (Gy) per fraction radiobiologic equivalence (EQD2) is 80–90 Gy, depending on tumor size at the time of brachytherapy. Dose limits for normal tissues are discussed.
These guidelines update those of 2000 and provide a comprehensive description of HDR cervical cancer brachytherapy in 2011.
To assess brachytherapy catheter positioning accuracy and to evaluate the effects of prolonged irradiation time on the tolerance dose of normal liver parenchyma following single-fraction irradiation with 192 Ir.
Materials and methods
Fifty patients with 76 malignant liver tumors treated by computed tomography (CT)-guided high-dose-rate brachytherapy (HDR-BT) were included in the study. The prescribed radiation dose was delivered by 1 - 11 catheters with exposure times in the range of 844 - 4432 seconds. Magnetic resonance imaging (MRI) datasets for assessing irradiation effects on normal liver tissue, edema, and hepatocyte dysfunction, obtained 6 and 12 weeks after HDR-BT, were merged with 3D dosimetry data. The isodose of the treatment plan covering the same volume as the irradiation effect was taken as a surrogate for the liver tissue tolerance dose. Catheter positioning accuracy was assessed by calculating the shift between the 3D center coordinates of the irradiation effect volume and the tolerance dose volume for 38 irradiation effects in 30 patients induced by catheters implanted in nearly parallel arrangement. Effects of prolonged irradiation were assessed in areas where the irradiation effect volume and tolerance dose volume did not overlap (mismatch areas) by using a catheter contribution index. This index was calculated for 48 irradiation effects induced by at least two catheters in 44 patients.
Positioning accuracy of the brachytherapy catheters was 5-6 mm. The orthogonal and axial shifts between the center coordinates of the irradiation effect volume and the tolerance dose volume in relation to the direction vector of catheter implantation were highly correlated and in first approximation identically in the T1-w and T2-w MRI sequences (p = 0.003 and p < 0.001, respectively), as were the shifts between 6 and 12 weeks examinations (p = 0.001 and p = 0.004, respectively). There was a significant shift of the irradiation effect towards the catheter entry site compared with the planned dose distribution (p < 0.005). Prolonged treatment time increases the normal tissue tolerance dose. Here, the catheter contribution indices indicated a lower tolerance dose of the liver parenchyma in areas with prolonged irradiation (p < 0.005).
Positioning accuracy of brachytherapy catheters is sufficient for clinical practice. Reduced tolerance dose in areas exposed to prolonged irradiation is contradictory to results published in the current literature. Effects of prolonged dose administration on the liver tolerance dose for treatment times of up to 60 minutes per HDR-BT session are not pronounced compared to effects of positioning accuracy of the brachytherapy catheters and are therefore of minor importance in treatment planning.
Intracavitary brachytherapy is an integral part of radiotherapy for locally advanced gynecologic malignancies. A dosimetric intercomparison of high dose rate intracavitary brachytherapy (HDR_BT) and intensity-modulated radiotherapy in cervical carcinoma has been made in the present study. CT scan images of 10 patients treated with HDR_BT were used for this study. A sliding-window IMRT (IMRT_SW) and step-and-shoot IMRT plans were generated using 6-MV X-rays. The cumulative dose volume histograms of target, bladder, rectum and normal tissue were analyzed for both techniques and dose distributions were compared. It was seen that the pear-shaped dose distribution characteristic of intracavitary brachytherapy with sharp dose fall-off outside the target could be achieved with IMRT. The integral dose to planning target volume was significantly higher with HDR_BT in comparison with IMRT. Significant differences between the two techniques were seen for doses to 1 cc and 2 cc of rectum, while the differences in 1 cc and 2 cc doses to bladder were not significant. The integral doses to the nontarget critical and normal structures were smaller with HDR_BT and with IMRT. It is concluded that IMRT can be the choice of treatment in case of non-availability of HDR brachytherapy facilities or when noninvasive treatments are preferred
Cervical carcinoma; high dose rate; intensity-modulated radiotherapy; intracavitary brachytherapy
BACKGROUND: External irradiation is an established palliative treatment for patients with inoperable lung cancer. However, persistent or recurrent symptoms due to local disase are common following external irradiation. The impact of high dose rate (HDR) brachytherapy in the palliative management of patients with local sequelae of residual or recurrent endobronchial lung carcinoma following external irradiation was investigated. METHODS: A prospective cohort of 29 patients (19 men, mean age 65 years) underwent HDR brachytherapy for inoperable lung cancer. All patients had completed external irradiation at least one month before entry into the study (mean (SD) dose 4400 (1481) cGy, completed 12.9 (21.3) months previously). Patients underwent outpatient bronchoscopic placement of 1-3 HDR brachytherapy catheters for delivery of 750-1000 cGy of intraluminal irradiation every two weeks on 1-3 occasions. Prospective evaluation before and four weeks after completion of HDR brachytherapy included assessment of indices of level of function, symptoms, extent of atelectasis (chest radiography), and bronchoscopic determination of degree of endobronchial obstruction. RESULTS: One hundred and eighteen catheters were placed in 81 treatments. Eleven of the 26 patients who underwent repeat bronchoscopy showed a reduction in the degree of endobronchial obstruction; five of 18 patients had radiographic improvement in the extent of atelectasis. Positive response rates ranged from 25% for signs and symptoms related to pneumonitis to 69% for haemoptysis. Performance status improved in 24% of patients. Two patients died before completion of the study protocol. Short term complications included one episode of non-fatal, massive haemoptysis, five of minor haemoptysis, and one pneumothorax. CONCLUSIONS: HDR brachytherapy may improve the degree of endobronchial obstruction, atelectasis, symptoms, and level of function with minimal short term complications in patients with recurrent or residual symptomatic disease following external irradiation.
Salvage therapy in head and neck cancer (HNC) is a controversy issue and the literature is scarce regarding the use of interstitial high-dose rate brachytherapy (I-HDR) in HNC. We evaluated the long-term results of a treatment policy combining salvage surgery and I-HDR for cervical recurrences of HNC. Charts of 21 patients treated from 1994 to 2004 were reviewed. The crude local control rate for all patients was 52.4%. The 5- and 8-years overall (OS) and local relapse-free survival (LRFS) rates were 50%, 42.9%, 42.5% and 28.6%, respectively. The only predictive factor associated to LFRS and OS was negative margin status (p = 0.0007 and p = 0.0002). We conclude that complete surgery is mandatory for long term control and the doses given by brachytherapy are not high enough to compensate for microscopic residual disease after surgery.
To estimate the rate of late grade 3 or greater genitourinary (GU) and gastrointestinal (GI) adverse events (AEs) following treatment with external beam radiation therapy and prostate high dose rate (HDR) brachytherapy.
Methods and Materials
Each participating institution submitted CT based HDR brachytherapy dosimetry data electronically for credentialing and for each study patient. Patients with locally confined T1c-T3b prostate cancer were eligible for this study. All patients were treated with 45 Gy in 25 fractions from external beam radiotherapy and one HDR implant delivering 19 Gy in 2 fractions. All AEs were graded according to CTCAEv3.0. Late GU/ GI AEs were defined as those occurring more than nine months from the start of the protocol treatment, in patients with at least 18 months of potential follow-up.
A total of 129 patients from 14 institutions were enrolled in this study. 125 patients were eligible and AE data was available for 112 patients. The pretreatment characteristics of the patients were as follows: T1c-T2c 91%, T3a-T3b 9%, PSA ≤ 10 70%, PSA >10-≤20 30%, GS 2-6 10%, GS 7 72%, and GS 8-10 18%. At a median follow-up time of 29.6 months, 3 acute and 4 late grade 3 GU/GI AEs were reported. The estimated rate of late grade 3-5 GU and GI AE at 18 months was 2.56%.
This is the first prospective, multi-institutional trial of CT based HDR brachytherapy and external beam radiotherapy. The technique and doses used in this study resulted in acceptable levels of adverse events.
Prostate cancer; High Dose Rate; Brachytherapy; Prospective multi-institutional clinical trial
Purpose. To assess the effectiveness of Ir-192 interstitial brachytherapy
as an adjunct to wide local excision as a functionsaving strategy for soft tissue sarcomas.
Subjects and methods. From September 1993 to April 1998, 20
consecutive patients diagnosed with soft tissue sarcomas were treated with a combination
of wide local excision and interstitial brachytherapy. In 16 patients brachytherapy was done
as an intraoperative procedure, while in four, the implant was performed post-operatively
under local anesthesia. Eleven of the 20 patients also received external beam radiotherapy
following the implant.
Results. After a mean follow-up of 27 months (4–54) the local control rate
for all 20 patients was 85% (17/20). In the 16 patients who had an intra-operative implant,
local control was 94% (15/16). In the four patients who underwent a post-operative implant,
local control was 50% (2/4). Actuarial 5-year survival was 90%. There were three cases (15%)
of severe local complications.
Conclusions. Wide local excision followed by low dose rate intersitital
brachytherapy have yielded a 85% local control rate in 20 patients with soft tissue sarcomas.
Local control rates were higher when the implants were done as an intra-operative procedure
than as a post-operative one.
Purpose: To evaluated prognostic factors and impact of the quality of planning of high dose rate brachytherapy (HDR-BT) for patients with local or locally advanced prostate cancer treated with external beam radiotherapy (EBRT) and HDR-BT.
Methods and Materials: Between 1997 and 2005, 209 patients with biopsy proven prostate adenocarcinoma were treated with localized EBRT and HDR-BT at the Department of Radiation-Oncology, Hospital A. C. Camargo, Sao Paulo, Brazil. Patient's age, Gleason score (GS), clinical stage (CS), initial PSA (iPSA), risk group for biochemical failure (GR), doses of EBRT and HDR-BT, use of three-dimensional planning for HDR-BT (3DHDR) and the Biological Effective Dose (BED) were evaluated as prognostic factors for biochemical control (bC).
Results: Median age and median follow-up time were 68 and 5.3 years, respectively. Median EBRT and HDR-BT doses were 45 Gy and 20 Gy. The crude bC at 3.3 year was 94.2%. For the Low, intermediate and high risk patients the bC rates at 3.3 years were 91.5%, 90.2% and 88.5%, respectively. Overall survival (OS) and disease specific survival rates at 3.3 years were 97.8% and 98.4%, respectively. On univariate analysis the prognostic factors related bC were GR (p= 0.040), GS ≤ 6 (p= 0.002), total dose of HDR-BT ≥ 20 Gy (p< 0.001), 3DHDR (p< 0.001), BED-HDR ≥ 99 Gy1.5 (p<0.001) and BED-TT ≥ 185 (p<0.001). On multivariate analysis the statistical significant predictive factors related to bC were RG (p< 0.001), HDR-BT ≥ 20 Gy (p=0.008) and 3DHDR (p<0.001).
Conclusions: we observed that the bC rates correlates with the generally accepted risk factors described in the literature. Dose escalation, evaluated through the BED, and the quality of planning of HDR-BT are also important predictive factors when treating prostate cancer.
high-dose rate brachytherapy; external beam radiotherapy; prostate cancer; RTOG-ASTRO Phoenix; biochemical failure; biochemical control
A survey of quality control (QC) currently undertaken in UK radiotherapy centres for high dose rate (HDR) and pulsed dose rate (PDR) brachytherapy has been conducted. The purpose was to benchmark current accepted practice of tests, frequencies and tolerances to assure acceptable HDR/PDR equipment performance. It is 20 years since a similar survey was conducted in the UK and the current review is timed to coincide with a revision of the IPEM Report 81 guidelines for quality control in radiotherapy.
Material and methods
All radiotherapy centres in the UK were invited by email to complete a comprehensive questionnaire on their current brachytherapy QC practice, including: equipment type, patient workload, source calibration method, level of image guidance for planning, prescribing practices, QC tests, method used, staff involved, test frequencies, and acceptable tolerance limits.
Survey data was acquired between June and August 2012. Of the 64 centres invited, 47 (73%) responded, with 31 centres having brachytherapy equipment (3 PDR) and fully completing the survey, 13 reporting no HDR/PDR brachytherapy, and 3 intending to commence HDR brachytherapy in the near future. All centres had comprehensive QC schedules in place and there was general agreement on key test frequencies and tolerances. Greatest discord was whether source strength for treatment planning should be derived from measurement, as at 58% of centres, or from the certified value, at 42%. IPEM Report 81 continues to be the most frequently cited source of QC guidance, followed by ESTRO Booklet No. 8.
A comprehensive survey of QC practices for HDR/PDR brachytherapy in UK has been conducted. This is a useful reference to which centres may benchmark their own practice. However, individuals should take a risk-assessment based approach, employing full knowledge of local equipment, clinical procedures and available test equipment in order to determine individual QC needs.
high dose rate (HDR); brachytherapy; quality control (QC); quality assurance (QA); survey
A technique for transperineal high-dose-rate (HDR) prostate brachytherapy and needle biopsy in a standard 1.5 T MRI scanner is demonstrated. In each of eight procedures (in four patients with intermediate to high risk localized prostate cancer), four MRI-guided transperineal prostate biopsies were obtained followed by placement of 14–15 hollow transperineal catheters for HDR brachytherapy. Mean needle-placement accuracy was 2.1 mm, 95% of needle-placement errors were less than 4.0 mm, and the maximum needle-placement error was 4.4 mm. In addition to guiding the placement of biopsy needles and brachytherapy catheters, MR images were also used for brachytherapy treatment planning and optimization. Because 1.5 T MR images are directly acquired during the interventional procedure, dependence on deformable registration is reduced and online image quality is maximized.
MRI; brachytherapy; prostate; prostatic neoplasms; biopsy; interventional MRI
To demonstrate the safety and efficacy of limited margin radiotherapy in the local control of pediatric and young adult patients with high grade non-rhabdomyosarcoma soft tissue sarcoma (NRSTS).
Methods and Materials
Pediatric patients with high-grade NRSTS requiring radiation were treated on an IRB approved prospective institutional study of conformal / intensity modulated / interstitial brachytherapy using a 2 cm anatomically constrained margin.
Thirty-two patients (median age 15.3 years, range 2–22 years) received adjuvant (27 patients) or definitive (5 patients) irradiation. With a median follow-up of 32 months, the 3-year cumulative incidence of local failure was 3.7% for patients irradiated after surgical resection. In total four patients experienced local failure; the mean dose to the volume of recurrence was ≥ 97% of the prescribed dose.
Delivery of limited margin radiotherapy using external beam or brachytherapy provides a high rate of local tumor control without marginal failure. Further follow-up is required to determine if normal tissue effects are minimized using this approach.
Soft-tissue sarcoma; Conformal; IMRT; Margin; Radiation
The optimal dosimetric parameters and planning techniques for high-dose-rate vaginal brachytherapy (HDR-VB) are unclear. Our aim was to evaluate the utility of bladder and rectal dosimetry for patients receiving HDR-VB for postoperative treatment of endometrial carcinoma.
Material and methods
Patients with endometrial cancer who underwent postoperative HDR-VB from January 1, 2004 through December 31, 2010 were included. All patients underwent primary surgery consisting of total hysterectomy and bilateral salpingo-oophrectomy (TH-BSO) with or without lymph node dissection and were treated with HDR-VB without pelvic external beam radiotherapy (EBRT) or chemotherapy. Demographic, pathologic, dosimetric and clinical data were collected.
One hundred patients were identified with the majority of patients receiving HDR-VB in 700 cGy × 3 fractions (45%) or 550 cGy x 4 fractions (53%). No plan was altered based on bladder dosimetry at the time of planning. The rate of acute urinary reactions (< 90 days from beginning of RT) grades 1 and 2 were 14% and 2%, respectively. The rate of late urinary reactions (> 90 days after RT) grades 1 and 2 were 7% and 3%, respectively. Dose to the bladder point did not correlate with urinary toxicity. No rectal toxicity was reported by patients receiving HDR-VB.
In the setting of HDR-VB without EBRT, the measured dose to the bladder point does not predict urinary toxicity and is very unlikely to indicate the need to change the treatment plan. The treatment of endometrial carcinoma utilizing HDR-VB alone is associated with very low rates of high-grade acute or late bladder toxicity.
endometrial cancer; high-dose-rate; brachytherapy
Millions of people are diagnosed with non-melanoma skin cancers (NMSC) worldwide each year. While surgical approaches are the standard treatment, some patients are appropriate candidates for radiation therapy for NMSC. High dose rate (HDR) brachytherapy using surface applicators has shown efficacy in the treatment of NMSC and shortens the radiation treatment schedule by using a condensed hypofractionated approach. An electronic brachytherapy (EBT) system permits treatment of NMSC without the use of a radioactive isotope.
Data were collected retrospectively from patients treated from July 2009 through March 2010. Pre-treatment biopsy was performed to confirm a malignant cutaneous diagnosis. A CT scan was performed to assess lesion depth for treatment planning, and an appropriate size of surface applicator was selected to provide an acceptable margin. An HDR EBT system delivered a dose of 40.0 Gy in eight fractions twice weekly with 48 hours between fractions, prescribed to a depth of 3-7 mm. Treatment feasibility, acute safety, efficacy outcomes, and cosmetic results were assessed.
Thirty-seven patients (mean age 72.5 years) with 44 cutaneous malignancies were treated. Of 44 lesions treated, 39 (89%) were T1, 1 (2%) Tis, 1 (2%) T2, and 3 (7%) lesions were recurrent. Lesion locations included the nose for 16 lesions (36.4%), ear 5 (11%), scalp 5 (11%), face 14 (32%), and an extremity for 4 (9%). Median follow-up was 4.1 months. No severe toxicities occurred. Cosmesis ratings were good to excellent for 100% of the lesions at follow-up.
The early outcomes of EBT for the treatment of NMSC appear to show acceptable acute safety and favorable cosmetic outcomes. Using a hypofractionated approach, EBT provides a convenient treatment schedule.
A modified form of high dose rate (HDR) brachytherapy has been developed called Axxent Electronic Brachytherapy (EBT). EBT uses a kilovolt X-ray source and does not require treatment in a shielded vault or a HDR afterloader unit. A multi-center clinical study was carried out to evaluate the success of treatment delivery, safety and toxicity of EBT in patients with endometrial cancer.
A total of 15 patients with stage I or II endometrial cancer were enrolled at 5 sites. Patients were treated with vaginal EBT alone or in combination with external beam radiation.
The prescribed doses of EBT were successfully delivered in all 15 patients. From the first fraction through 3 months follow-up, there were 4 CTC Grade 1 adverse events and 2 CTC Grade II adverse events reported that were EBT related. The mild events reported were dysuria, vaginal dryness, mucosal atrophy, and rectal bleeding. The moderate treatment related adverse events included dysuria, and vaginal pain. No Grade III or IV adverse events were reported. The EBT system performed well and was associated with limited acute toxicities.
EBT shows acute results similar to HDR brachytherapy. Additional research is needed to further assess the clinical efficacy and safety of EBT in the treatment of endometrial cancer.
To determine current practice patterns with regard to gynecologic high-dose-rate (HDR) brachytherapy among international members of the Gynecologic Cancer Intergroup (GCIG) in Japan/Korea (Asia), Australia/New Zealand (ANZ), Europe (E) and North America (NAm).
Materials and Methods
A 32-item survey was developed requesting information on brachytherapy practice patterns and standard management for Stage IB-IVA cervical cancer. The chair of each GCIG member cooperative group selected radiation oncology members to receive the survey.
A total of 72 responses were analyzed; 61 respondents (85%) utilized HDR. The three most common HDR brachytherapy fractionation regimens for Stage IB-IIA patients were 6 Gy for 5 fractions (18%), 6 Gy × 4 (15%), 7 Gy × 3 (11%), and for Stage IIB-IVA patients were 6 Gy for 5 fractions (19%), 7 Gy × 4 (8%), and 7 Gy × 3 (8%). Overall, the mean combined external-beam and brachytherapy equivalent dose (EQD2) was 81.1 (standard deviation [SD], 10.16). The mean EQD2 recommended for Stage IB-IIA patients was 78.9 Gy (SD, 10.7) and for Stage IIB-IVA was 83.3 Gy (SD, 11.2) (p=0.02). By region, the mean combined EQD2 was: Asia, 71.2 Gy (SD, 12.65); ANZ, 81.18 (SD, 4.96); E, 83.24 (SD, 10.75); and NAm, 81.66 (SD, 6.05; p=0.02 for Asia vs. other regions). The ratio of brachytherapy to total prescribed dose was significantly higher for Japan (p=0.0002).
Although fractionation patterns may vary, the overall mean dose administered for cervical cancer is similar in Australia/New Zealand, Europe and North America, with practitioners in Japan administering a significantly lower external-beam dose but higher brachytherapy dose to the cervix. Given common goals, standardization should be possible in future clinical trials.
brachytherapy; cervical cancer; radiation dose
To compare the results of external beam radiotherapy in combination with 3D- computed tomography (CT)-implanted interstitial high dose rate brachytherapy (ERT/3D-HDR-BT) versus conventional external beam radiotherapy (ERT) for the treatment of stage T2b nasopharyngeal carcinoma (NPC).
Forty NPC patients diagnosed with stage T2b NPC were treated with ERT/3D-HDR-BT under local anesthesia. These patients received a mean dose of 60 Gy, followed by 12-20 Gy administered by 3D-HDR-BT. Another 101 patients diagnosed with non-metastatic T2b NPC received a mean dose of 68 Gy by ERT alone during the same period.
Patients treated with ERT/3D-HDR-BT versus ERT alone exhibited an improvement in their 5-y local failure-free survival rate (97.5% vs. 80.2%, P = 0.012) and disease-free survival rate (92.5% vs. 73.3%, P = 0.014). Using multivariate analysis, administration of 3D-HDR-BT was found to be favorable for local control (P = 0.046) and was statistically significant for disease-free survival (P = 0.021). The incidence rate of acute and chronic complications between the two groups was also compared.
It is possible that the treatment modality enhances local control due to improved conformal dose distributions and the escalated radiation dose applied.
Radical radiotherapy is one of the options for the management of prostate cancer. In external beam therapy, 3D conformal radiotherapy (3DCRT) and intensity modulated radiotherapy (IMRT) are the options for delivery of increased radiation dose, as vital organs are very close to the prostate and a higher dose to these structures leads to an increased toxicity. In brachytherapy, low dose rate brachytherapy with permanent implant of radioactive seeds and high dose rate brachytherapy (HDR) with remote after loaders are available. A dosimetric analysis has been made on IMRT and HDR brachytherapy plans. Ten cases from each IMRT and HDR brachytherapy have been taken for the study. The analysis includes comparison of conformity and homogeneity indices, D100, D95, D90, D80, D50, D10 and D5 of the target. For the organs at risk (OAR), namely rectum and bladder, V100, V90 and V50 are compared. In HDR brachytherapy, the doses to 1 cc and 0.1 cc of urethra have also been studied. Since a very high dose surrounds the source, the 300% dose volumes in the target and within the catheters are also studied in two plans, to estimate the actual volume of target receiving dose over 300%. This study shows that the prescribed dose covers 93 and 92% of the target volume in IMRT and HDR brachytherapy respectively. HDR brachytherapy delivers a much lesser dose to OAR, compared to the IMRT. For rectum, the V50 in IMRT is 34.0cc whilst it is 7.5cc in HDR brachytherapy. With the graphic optimization tool in HDR brachytherapy planning, the dose to urethra could be kept within 120% of the target dose. Hence it is concluded that HDR brachytherapy may be the choice of treatment for cancer of prostate in the early stage.
Brachytherapy; conformity; intensity modulated radiotherapy; prostate
This study was performed to evaluate the treatment results, prognostic factors and complication rates in patients with locally advanced cancer of uterine cervix after radiotherapy with high-dose rate (HDR) brachytherapy.
Materials and Methods
One hundred and twenty patients with a locally advanced (stages IIB~IVA according to FIGO classification) carcinoma of the uterine cervix were treated with radiotherapy at the Department of Radiation Oncology, Samsung Medical Center between September 1994 and December 2001. The median age of the patients was 61 years (range 29 to 81). Sixty-one, 56 and 3 patients had FIGO stage IIB, III, and IV diseases, respectively. All patients were given external beam radiotherapy over the whole pelvis (median 50.4 Gy) and HDR intracavitary brachytherapy, with a median of 4 Gy per fraction, to point A. Twenty-one patients received chemotherapy, of which 13 and 21 received neoadjuvant chemotherapy and concurrent chemotherapy, respectively, during the first and fourth weeks of external beam radiotherapy. The chemotherapy was not randomly assigned and the median follow-up time was 28.5 months (range: 6~100 months).
The three- and 5-year overall survival (OS) and disease-free survival (DFS) rates were 64.4 and 57.0%, and 63.7 and 60.2%, respectively. The 5-year OS and DFS rates of the patients at stages IIB, III and IV were 60.2, 57.9 and 33.3%, and 57.4, 65.4 and 33.3%, respectively. Univariate analysis indicated that the FIGO stage, overall treatment time (OTT) and treatment response were significant variables for the OS (p=0.035, p=0.0649 and p=0.0009) and of the DFS (p=0.0009, p=0.0359 and p=0.0363). Multivariate analysis showed that the treatment response was the only significant variable for the OS (p=0.0018) and OTT for the DFS (p=0.0360). The overall incidence of late complications in the rectum and bladder were 11.7 and 6.7%, respectively. In addition, insufficiency fractures were observed in 7 patients (5.8%).
The results of this study suggest that radical radiotherapy with HDR brachytherapy was appropriate for the treatment of locally advanced uterine cervix cancer. Also, the response after treatment and OTT are significant prognostic factors.
Radiotherapy; Advanced cancer of the uterine cervix; High-dose rate brachytherapy
Orthogonal film-based treatment planning is the most commonly adopted standard practice of treatment planning for cancer of the uterine cervix using high dose rate brachytherapy (HDR). This study aims at examining the variation in rectal and bladder doses when the same set of orthogonal films was given to different observers. Five physicists were given 35 pairs of orthogonal films obtained from patients who had undergone HDR brachytherapy. They were given the same instructions and asked to plan the case assuming the tumor was centrally placed, using the treatment-planning system, PLATO BPS V13.2. A statistically significant difference was observed in the average rectal (F = 3.407, P = 0.01) and bladder (F = 3.284, P = 0.013) doses and the volumes enclosed by the 100% isodose curve (P < 0.01) obtained by each observer. These variations may be attributed to the differences in the reconstruction of applicators, the selection of source positions in ovoids and the intrauterine (IU) tube, and the differences in the selection of points especially for the rectum, from lateral radiographs. These variations in planning seen within a department can be avoided if a particular source pattern is followed in the intrauterine tube, unless a specific situation demands a change. Variations in the selection of rectal points can be ruled out if the posterior vaginal surface is clearly seen.
High dose rate brachytherapy; interobserver variation; uterine cervix
Low-dose rate brachytherapy has become a mainstream treatment option for men diagnosed with prostate cancer because of excellent long-term treatment outcomes in low-, intermediate-, and high-risk patients. To a great extend due to patient lead advocacy for minimally invasive treatment options, high-quality prostate implants have become widely available in the US, Europe, and Japan. High-dose-rate (HDR) afterloading brachytherapy in the management of localised prostate cancer has practical, physical, and biological advantages over low-dose-rate seed brachytherapy. There are no free live sources used, no risk of source loss, and since the implant is a temporary procedure following discharge no issues with regard to radioprotection use of existing facilities exist. Patients with localized prostate cancer may benefit from high-dose-rate brachytherapy, which may be used alone in certain circumstances or in combination with external-beam radiotherapy in other settings. The purpose of this paper is to present the essentials of brachytherapies techniques along with the most important studies that support their effectiveness in the treatment of prostate cancer.