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1.
J Clin Oncol ; 35(15): 1737-1743, 2017 May 20.
Article in English | MEDLINE | ID: mdl-28346805

ABSTRACT

Purpose To jointly update the Cancer Care Ontario guideline on brachytherapy for patients with prostate cancer to account for new evidence. Methods An Update Panel conducted a targeted systematic literature review and identified more recent randomized controlled trials comparing dose-escalated external beam radiation therapy (EBRT) with brachytherapy in men with prostate cancer. Results Five randomized controlled trials provided the evidence for this update. Recommendations For patients with low-risk prostate cancer who require or choose active treatment, low-dose rate brachytherapy (LDR) alone, EBRT alone, and/or radical prostatectomy (RP) should be offered to eligible patients. For patients with intermediate-risk prostate cancer choosing EBRT with or without androgen-deprivation therapy, brachytherapy boost (LDR or high-dose rate [HDR]) should be offered to eligible patients. For low-intermediate risk prostate cancer (Gleason 7, prostate-specific antigen < 10 ng/mL or Gleason 6, prostate-specific antigen, 10 to 20 ng/mL), LDR brachytherapy alone may be offered as monotherapy. For patients with high-risk prostate cancer receiving EBRT and androgen-deprivation therapy, brachytherapy boost (LDR or HDR) should be offered to eligible patients. Iodine-125 and palladium-103 are each reasonable isotope options for patients receiving LDR brachytherapy; no recommendation can be made for or against using cesium-131 or HDR monotherapy. Patients should be encouraged to participate in clinical trials to test novel or targeted approaches to this disease. Additional information is available at www.asco.org/Brachytherapy-guideline and www.asco.org/guidelineswiki .


Subject(s)
Brachytherapy/methods , Brachytherapy/standards , Prostatic Neoplasms/radiotherapy , Humans , Male , Randomized Controlled Trials as Topic
2.
Brachytherapy ; 16(2): 313-322, 2017.
Article in English | MEDLINE | ID: mdl-28017293

ABSTRACT

PURPOSE: To evaluate the incidence of acute urinary toxicity after permanent seed prostate brachytherapy (BT) over a 15-year period. METHODS AND MATERIALS: The study consisted of 782 prostate cancer patients treated with BT. All patients completed self-administered International Prostate Symptoms Score (IPSS) at baseline and during regular follow-up. We evaluated the risk of acute urinary retention (AUR) up to 3 months post-BT and lower urinary tract symptom (LUTS) resolution (defined as return to within two points of baseline IPSS score) at regular intervals, up to 24 months post-BT. Univariate and multivariate logistic regressions were used to evaluate the effect of various patient, tumor, and treatment factors on the risk of AUR and the likelihood of LUTS resolution. RESULTS: Ninety-six patients (12%) developed AUR at a median of 1 day post-BT. Increased peak urinary flow is independently associated with lower risk of AUR (odds ratio [OR] = 0.94; 95% confidence interval [CI] = 0.91-0.97). Decline in incidence of AUR was observed over time with increased institutional experience (p = 0.03). Of the 646 patients with a minimum of 24-month follow-up, 29%, 49%, and 72% had LUTS resolution at 6, 12, and 24 months, respectively. Patients who had pre-BT transurethral resection of prostate (OR = 2.4; 95% CI = 1.5-4.0), cytoreductive neo-adjuvant androgen deprivation (OR = 2.0; 95% CI = 1.0-4.0), and higher baseline IPSS (OR = 1.1; 95% CI = 1.07-1.19) are more likely to report LUTS resolution at 24 months. CONCLUSIONS: We reported decline in AUR over time with increased institutional experience in one of the largest Australasian BT series. Approximately three-quarters of patients achieved LUTS resolution at 24-month follow-up.


Subject(s)
Brachytherapy/adverse effects , Prostatic Neoplasms/radiotherapy , Radiation Injuries/etiology , Urinary Retention/etiology , Acute Disease , Aged , Brachytherapy/methods , Brachytherapy/standards , Chemotherapy, Adjuvant , Clinical Competence , Follow-Up Studies , Humans , Incidence , Male , Middle Aged , Neoadjuvant Therapy , Neoplasm Grading , Prostatic Neoplasms/pathology , Prostatic Neoplasms/therapy , Severity of Illness Index , Transurethral Resection of Prostate , Urinary Bladder/pathology
4.
PLoS One ; 9(12): e115155, 2014.
Article in English | MEDLINE | ID: mdl-25521914

ABSTRACT

High dose rate brachytherapy (HDR) using 192Ir sources is well accepted as an important treatment option and thus requires an accurate dosimetry standard. However, a dosimetry standard for the direct measurement of the absolute dose to water for this particular source type is currently not available. An improved standard for the absorbed dose to water based on Fricke dosimetry of HDR 192Ir brachytherapy sources is presented in this study. The main goal of this paper is to demonstrate the potential usefulness of the Fricke dosimetry technique for the standardization of the quantity absorbed dose to water for 192Ir sources. A molded, double-walled, spherical vessel for water containing the Fricke solution was constructed based on the Fricke system. The authors measured the absorbed dose to water and compared it with the doses calculated using the AAPM TG-43 report. The overall combined uncertainty associated with the measurements using Fricke dosimetry was 1.4% for k = 1, which is better than the uncertainties reported in previous studies. These results are promising; hence, the use of Fricke dosimetry to measure the absorbed dose to water as a standard for HDR 192Ir may be possible in the future.


Subject(s)
Brachytherapy/standards , Ferrous Compounds/radiation effects , Iridium Radioisotopes/therapeutic use , Radiometry/methods , Solutions/radiation effects , Absorption, Radiation , Algorithms , Brachytherapy/methods , Feasibility Studies , Radiotherapy Dosage/standards , Water/chemistry
5.
J Cancer Res Ther ; 9(3): 402-9, 2013.
Article in English | MEDLINE | ID: mdl-24125974

ABSTRACT

PURPOSE: For the treatment of nasopharnx carcinoma (NPC) using brachytherapy methods and high-energy photon sources are common techniques. In the common three dimensional (3D) treatments planning, all of the computed tomography images are assumed homogeneous. This study presents the results of Monte Carlo calculations for non-homogeneous nasopharynx phantom, MAGICA normoxic gel dosimetry and 3D treatment planning system (TPS). MATERIALS AND METHODS: The head phantom was designed with Plexiglas cylinder, head bone, and nasopharynx brachytherapy silicon applicator. For the simulations, version 5 of the Monte Carlo N-particle transport code (MCNP5) was used. 3D treatment planning was performed in Flexiplan software. A normoxic radiosensitive polymer gel was fabricated under normal atmospheric conditions and poured into test tubes (for calibration curve) and the head phantom. In addition, the head phantom was irradiated with Flexitron afterloader brachytherapy machine with (192)Ir source. To obtain calibration curves, 11 dosimeters were irradiated with dose range of 0-2000 cGy. Evaluations of dosimeters were performed on 1.5T scanner. RESULTS: Two-dimensional iso-dose in coronal plan at distances of z = +0.3, -0.3 cm was calculated. There was a good accordance between 3D TPS and MCNP5 simulation and differences in various distances were between 2.4% and 6.1%. There was a predictable accordance between MAGICA gel dosimetry and MCNP5 simulation and differences in various distances were between 5.7% and 7.4%. Moreover, there was an acceptable accordance between MAGICA gel dosimetry and MCNP5 data and differences in various distances were between 5.2% and 9.4%. CONCLUSION: The sources of differences in this comparison are divided to calculations variation and practical errors that was added in experimental dosimetry. The result of quality assurance of nasopharynx high dose rate brachytherapy is consistent with international standards.


Subject(s)
Brachytherapy/methods , Brachytherapy/standards , Computer Simulation , Monte Carlo Method , Nasopharyngeal Neoplasms/radiotherapy , Radiotherapy Planning, Computer-Assisted , Brachytherapy/instrumentation , Carcinoma , Humans , Magnetic Resonance Imaging , Nasopharyngeal Carcinoma , Phantoms, Imaging , Radiometry , Radiotherapy Dosage
6.
Article in Russian | MEDLINE | ID: mdl-23718082

ABSTRACT

The objective of the present study was to provide hygienic assessment of hospital wards equipped with the therapeutic sylvinite screens (TSS) and compare the results of the treatment of 80 patients suffering vulgar psoriasis with the use of TSS and without them. The sylvinite screens made it possible to create comfortable microenvironment in the wards and moderately increased the radiation background (0,15+/-0,005 Sv/hour) thereby promoting saturation of the ward atmosphere with aeroions dominated by the light negative particles (491,5+/-14,4 units/cm3). Such healthy environment hadc beneficial effect on the clinical course of the psoriatic process, the state of functional systems of the patients and their quality of life. It is concluded that the introduction of halotherapy in the treatment in patients presenting with vulgar psoriasis makes it possible to achieve clinical remission in 65% of them compared with 20% of the patients given the traditional treatment.


Subject(s)
Brachytherapy/methods , Hygiene/standards , Microclimate , Minerals/therapeutic use , Psoriasis/therapy , Speleotherapy/methods , Adolescent , Adult , Brachytherapy/standards , Combined Modality Therapy , Humans , Middle Aged , Psoriasis/diagnosis , Psoriasis/drug therapy , Psoriasis/psychology , Quality of Life , Skin/drug effects , Skin/radiation effects , Speleotherapy/standards , Young Adult
7.
Australas Phys Eng Sci Med ; 35(3): 291-6, 2012 Sep.
Article in English | MEDLINE | ID: mdl-22766686

ABSTRACT

Successful treatment for permanent implant brachytherapy is based on accurate measurement of dosimetry parameters for the seed sources. Literature describes the application of various types of phantom to determine the AAPM TG-43 dosimetry parameters for permanent implant seeds. Previously we created a new type of phantom used to measure the dosimetry parameters of a high dose-rate (192)Ir source. In this study, we modified the phantom to suit to a common type of (125)I seed source (Sinko BT-125-1). The dose-rate constant, radial dose function and anisotropy function of this source were measured in detail and compared with the published values of other similar in-design (125)I seed sources. The experimental results exhibit fairly small measurement uncertainties and good self-consistency. The modified phantom is demonstrated on the measurement of dosimetry parameters for the Sinko BT-125-1 (125)I seed, however, it could easily be used for similar measurements of other permanent implantation seed sources.


Subject(s)
Brachytherapy/instrumentation , Brachytherapy/standards , Iodine Radioisotopes/analysis , Iodine Radioisotopes/standards , Polystyrenes/radiation effects , Prostheses and Implants , Radiometry/instrumentation , Dose-Response Relationship, Radiation , Internationality , Radiation Dosage , Radiometry/methods , Radiometry/standards , Reproducibility of Results , Sensitivity and Specificity
8.
Int J Radiat Oncol Biol Phys ; 82(5): e795-801, 2012 Apr 01.
Article in English | MEDLINE | ID: mdl-22330999

ABSTRACT

PURPOSE: External-beam radiation therapy combined with low-doserate permanent brachytherapy are commonly used to treat men with localized prostate cancer. This Phase II trial was performed to document late gastrointestinal or genitourinary toxicity as well as biochemical control for this treatment in a multi-institutional cooperative group setting. This report defines the long-term results of this trial. METHODS AND MATERIALS: All eligible patients received external-beam radiation (45 Gy in 25 fractions) followed 2-6 weeks later by a permanent iodine 125 implant of 108 Gy. Late toxicity was defined by the Radiation Therapy Oncology Group/European Organization for Research and Treatment of Cancer late radiation morbidity scoring scheme. Biochemical control was defined by the American Society for Therapeutic Radiology and Oncology (ASTRO) Consensus definition and the ASTRO Phoenix definition. RESULTS: One hundred thirty-eight patients were enrolled from 20 institutions, and 131 were eligible. Median follow-up (living patients) was 8.2 years (range, 2.7-9.3 years). The 8-year estimate of late grade >3 genitourinary and/or gastrointestinal toxicity was 15%. The most common grade >3 toxicities were urinary frequency, dysuria, and proctitis. There were two grade 4 toxicities, both bladder necrosis, and no grade 5 toxicities. In addition, 42% of patients complained of grade 3 impotence (no erections) at 8 years. The 8-year estimate of biochemical failure was 18% and 21% by the Phoenix and ASTRO consensus definitions, respectively. CONCLUSION: Biochemical control for this treatment seems durable with 8 years of follow-up and is similar to high-dose external beam radiation alone or brachytherapy alone. Late toxicity in this multi-institutional trial is higher than reports from similar cohorts of patients treated with high-dose external-beam radiation alone or permanent low-doserate brachytherapy alone, perhaps suggesting further attention to strategies that limit doses to normal structures or to unimodal radiotherapy techniques.


Subject(s)
Adenocarcinoma/pathology , Adenocarcinoma/radiotherapy , Organs at Risk/radiation effects , Prostatic Neoplasms/pathology , Prostatic Neoplasms/radiotherapy , Radiation Injuries/complications , Adenocarcinoma/blood , Adult , Aged , Aged, 80 and over , Brachytherapy/adverse effects , Brachytherapy/methods , Brachytherapy/standards , Dose Fractionation, Radiation , Erectile Dysfunction/etiology , Follow-Up Studies , Gastrointestinal Tract/radiation effects , Humans , Iodine Radioisotopes/adverse effects , Iodine Radioisotopes/therapeutic use , Male , Middle Aged , Neoplasm Grading , Proctitis/etiology , Prostate-Specific Antigen/blood , Prostatic Neoplasms/blood , Radiotherapy/adverse effects , Radiotherapy/methods , Risk , Urination Disorders/etiology , Urogenital System/radiation effects
9.
Brachytherapy ; 11(1): 58-67, 2012.
Article in English | MEDLINE | ID: mdl-22265439

ABSTRACT

PURPOSE: To develop recommendations for the use of adjuvant vaginal cuff brachytherapy after hysterectomy and update previous American Brachytherapy Society (ABS) guidelines. METHODS AND MATERIALS: A panel of members of the ABS performed a literature review, supplemented their clinical experience, and formulated recommendations for adjuvant vaginal cuff brachytherapy. RESULTS: The ABS endorses the National Comprehensive Cancer Network guidelines for indications for radiation therapy for patients with endometrial cancer and cervical cancer and the guidelines on quality assurance of the American Association on Physicists in Medicine. The ABS made specific recommendations for applicator selection, insertion techniques, target volume definition, dose fractionation, and specifications for postoperative adjuvant vaginal cuff therapy. The ABS recommends that applicator selection should be based on patient anatomy, target volume geometry, and physician judgment. The dose prescription point should be clearly specified. Suggested doses were tabulated for treatment with brachytherapy alone, and in combination with external beam radiation therapy, when applicable. A properly fitted brachytherapy applicator should be selected that conforms to the vaginal apex and achieves mucosal contact with optimal tumor and normal tissue dosimetry. Dose prescription points may be individually selected but doses should be reported at the vaginal surface and at 0.5-cm depth. CONCLUSIONS: Recommendations are made for adjuvant vaginal cuff brachytherapy. Practitioners and cooperative groups are encouraged to use these recommendations to formulate their treatment and dose reporting policies. These recommendations will permit meaningful comparisons of reports from different institutions and lead to better and more appropriate use of vaginal brachytherapy.


Subject(s)
Brachytherapy/instrumentation , Brachytherapy/standards , Practice Guidelines as Topic , Radiotherapy, Adjuvant/instrumentation , Radiotherapy, Adjuvant/standards , Vaginal Neoplasms/radiotherapy , Vaginal Neoplasms/surgery , Female , Humans , Postoperative Care/standards , United States
10.
Radiother Oncol ; 100(3): 456-62, 2011 Sep.
Article in English | MEDLINE | ID: mdl-21963285

ABSTRACT

BACKGROUND AND PURPOSE: The feasibility of a real-time in vivo dosimeter to detect errors has previously been demonstrated. The purpose of this study was to: (1) quantify the sensitivity of the dosimeter to detect imposed treatment errors under well controlled and clinically relevant experimental conditions, and (2) test a new statistical error decision concept based on full uncertainty analysis. MATERIALS AND METHODS: Phantom studies of two gynecological cancer PDR and one prostate cancer HDR patient treatment plans were performed using tandem ring applicators or interstitial needles. Imposed treatment errors, including interchanged pairs of afterloader guide tubes and 2-20mm source displacements, were monitored using a real-time fiber-coupled carbon doped aluminum oxide (Al(2)O(3):C) crystal dosimeter that was positioned in the reconstructed tumor region. The error detection capacity was evaluated at three dose levels: dwell position, source channel, and fraction. The error criterion incorporated the correlated source position uncertainties and other sources of uncertainty, and it was applied both for the specific phantom patient plans and for a general case (source-detector distance 5-90 mm and position uncertainty 1-4mm). RESULTS: Out of 20 interchanged guide tube errors, time-resolved analysis identified 17 while fraction level analysis identified two. Channel and fraction level comparisons could leave 10mm dosimeter displacement errors unidentified. Dwell position dose rate comparisons correctly identified displacements ≥ 5mm. CONCLUSION: This phantom study demonstrates that Al(2)O(3):C real-time dosimetry can identify applicator displacements ≥ 5mm and interchanged guide tube errors during PDR and HDR brachytherapy. The study demonstrates the shortcoming of a constant error criterion and the advantage of a statistical error criterion.


Subject(s)
Brachytherapy/standards , Genital Neoplasms, Female/radiotherapy , Medical Errors/prevention & control , Prostatic Neoplasms/radiotherapy , Radiometry/instrumentation , Aluminum Oxide , Brachytherapy/instrumentation , Dose Fractionation, Radiation , Equipment Design , Feasibility Studies , Female , Humans , Male , Monte Carlo Method , Needles , Quality Assurance, Health Care , Radiotherapy Dosage , Sensitivity and Specificity , Titanium
11.
Radiat Prot Dosimetry ; 120(1-4): 95-9, 2006.
Article in English | MEDLINE | ID: mdl-16644958

ABSTRACT

A thermoluminescence dosimetry (TLD) system was characterised at SSDL-ININ to verify the air-kerma strength (S(K)) and dose-to-water (D(W)) values for (137)Cs sources used in low dose rate (LDR) brachytherapy treatments at the Hospital General de Mexico (HGM). It consists of a Harshaw 3500 reader and a set of TLD-100 powder capsules. The samples of TLD-100 powder were calibrated in terms of D(W) vs. nC or nC mg(-1), and their dose response curves were corrected for supralinearity. The D(W) was calculated using the AAPM TG-43 formalism using S(K) for a CDCSM4 (137)Cs reference source. The S(K) value was obtained by using a NE 2611 chamber, and with two well chambers. The angular anisotropy factor was measured with the NE 2611 chamber for this source. The HGM irradiated TLD-100 powder capsules to a reference dose D(W) of 2 Gy with their (137)Cs sources. The percent deviations between the imparted and reference doses were 1.2% < or = Delta < or = 6.5%, which are consistent with the combined uncertainties: 5.6% < or = u(c) < or = 9.8% for D(W).


Subject(s)
Brachytherapy/standards , Cesium Radioisotopes/analysis , Cesium Radioisotopes/therapeutic use , Thermoluminescent Dosimetry/methods , Thermoluminescent Dosimetry/standards , Water , Body Burden , Brachytherapy/methods , Mexico , Radiotherapy Dosage , Reference Values , Relative Biological Effectiveness
12.
Australas Phys Eng Sci Med ; 28(3): 196-9, 2005 Sep.
Article in English | MEDLINE | ID: mdl-16250476

ABSTRACT

Calibration of a High-Dose-Rate 1000 Plus ionisation chamber and associated electrometer for the determination of reference air kerma rate for 125I brachytherapy seeds has been developed. Traceability was established from ionisation chamber measurements of an Amersham model 6711 125I seed for which a primary standard measurement of reference air kerma rate has been made by the National Institute of Standards and Technology. The status of an Australian secondary standard is to be realised by establishing legal verifying authority from the National Measurement Institute. The calibrated chamber thus provides a measurement from which similar chambers in hospitals may be calibrated. For quality assurance this result was compared with the calibration certificate supplied by the Accredited Dosimetry Calibration Laboratory of the University of Wisconsin, USA.


Subject(s)
Brachytherapy/standards , Guidelines as Topic , Iodine Radioisotopes/analysis , Iodine Radioisotopes/standards , Radiometry/instrumentation , Radiometry/standards , Australia , Body Burden , Calibration/standards , Radiometry/methods , Radiotherapy Dosage , Reference Standards , Relative Biological Effectiveness , Reproducibility of Results , Sensitivity and Specificity
13.
Curr Treat Options Oncol ; 5(6): 463-76, 2004 Dec.
Article in English | MEDLINE | ID: mdl-15509480

ABSTRACT

When treating soft tissue sarcomas (STS) of the extremities, the major therapeutic goals are survival, local tumor control, optimal function, and minimal morbidity. Surgical resection of the primary tumor is the essential component of treatment for virtually all patients. However, local control by surgery alone is poor for the majority of patients with extremity lesions unless the procedure removes large volumes of grossly normal tissue (ie, widely negative margins are attained, because sarcomas tend to infiltrate normal tissue adjacent to the evident lesion). Thus, removal of the gross lesion by a simple excision alone is followed by local recurrence in 60% to 90% of patients. Radical resections reduce the local recurrence rate to 10% to 30%, but may compromise limb function. The combination of function-sparing surgery and radiation achieves better outcomes than either treatment alone for nearly all patients with STS. Because both surgical and radiation technique are critically important for optimizing local control of tumor and functional outcome, it is important to manage these patients in dedicated multispecialty clinics comprised of physicians with expertise in sarcomas, including orthopedic and general oncologic surgeons, radiation oncologists, medical oncologists, sarcoma pathologists, and bone and soft tissue diagnostic radiologists. Radiation therapy can be given by external beam radiation therapy (EBRT) or brachytherapy (BRT) or combination thereof. External beam radiation can be given either preoperatively or postoperatively. The clinical considerations and the outcome data that must be considered in choosing the most appropriate treatment technique for the individual patient are discussed.


Subject(s)
Extremities , Sarcoma/radiotherapy , Sarcoma/surgery , Soft Tissue Neoplasms/radiotherapy , Soft Tissue Neoplasms/surgery , Brachytherapy/standards , Combined Modality Therapy , Humans , Neoplasm Recurrence, Local , Phototherapy/standards , Radiation Dosage , Radiotherapy/adverse effects , Radiotherapy/standards , Radiotherapy, Adjuvant/standards , Sarcoma/pathology , Soft Tissue Neoplasms/pathology , Treatment Outcome , Wound Healing
14.
Int J Radiat Oncol Biol Phys ; 60(2): 648-53, 2004 Oct 01.
Article in English | MEDLINE | ID: mdl-15380602

ABSTRACT

PURPOSE: To evaluate, in a retrospective review, prostate brachytherapy dosimetry outcomes relative to the transurethral resection of the prostate (TURP) cavity size to address the theoretical concern that an intraprostatic cavity may hinder adequate radioactive source placement. METHODS AND MATERIALS: A total of 73 patients who underwent prostate brachytherapy as part of their treatment of localized prostate cancer had a history of a prior TURP. Of these 73 patients, 37 underwent (125)I implantation, 19 (103)Pd implantation, and 17 partial (103)Pd implantation. The dose was calculated using the dose to 90% of the prostate gland (D(90)) from the 1-month post-implant dosimetric analysis. The doses were normalized relative to 100% of the prescription dose. Archived transrectal ultrasound images were used to determine the maximal length and width of the visible residual TURP cavities. The prolate spheroid or symmetric egg shape was used to calculate each residual cavity volume. The derived volume of the TURP cavity was divided by the measured ultrasound volume of the prostate at brachytherapy, creating a percentage of volume measurement for each prostate. All p values, unless otherwise specified, were generated by comparing patients without a visible TURP defect with the subgroups of patients with a visible defect using the Student t test. RESULTS: A visible residual TURP defect was noted on the operative transrectal ultrasound images of 55 (75%) of the 73 patients with a history of TURP before brachytherapy. The 18 patients without a visible TURP defect had a median D(90) of 96% and were used for subsequent statistical comparison. Thirty-six patients with a TURP defect <10% of the entire prostate volume had a median D(90) of 109% (p = 0.02). Thirteen patients with a TURP defect between 10% and 20% of the prostate volume had a median D(90) of 112% (p = 0.03). Six patients with a TURP defect >20% of the prostate volume had a D(90) of 89% (p = 0.43). CONCLUSION: A visible residual TURP cavity that is assumed to have a prolate spheroid shape and occupy >/=10% of a prostate volume did not appear to be a statistically significant hindrance to proper dosimetric outcome.


Subject(s)
Brachytherapy/standards , Prostatic Neoplasms/radiotherapy , Prostatic Neoplasms/surgery , Transurethral Resection of Prostate , Brachytherapy/instrumentation , Contraindications , Humans , Iodine Radioisotopes/therapeutic use , Male , Palladium/therapeutic use , Prostate/diagnostic imaging , Prostate/pathology , Prostatic Neoplasms/diagnostic imaging , Radioisotopes/therapeutic use , Radiotherapy Dosage , Retrospective Studies , Ultrasonography
15.
Cancer Radiother ; 8 Suppl 1: S50-5, 2004 Nov.
Article in French | MEDLINE | ID: mdl-15679247

ABSTRACT

ICRP (International Commission for Radiological Protection) Committee 3 ("Radioprotection in medicine") is currently finalizing two recommendations about Brachytherapy. The first text, from Task Group (TG) 53, is focussing on the prevention of high-dose-rate brachytherapy accidents. It reminds the reader of the 500 accidents/incidents which have been reported so far in the literature, and reports in details on some representative accidents. Building on those data, the text gives general and specific recommendations, aiming at reducing both the frequency and the severity of those accidents. The second text, from Task Group 57, considers the radiation safety aspects of brachytherapy for prostate cancer using permanently implanted sources. For this topic, no severe accident has never been reported so far. However, some radioprotection problems arose, due to the dose received from the patients, to migrating seeds and to cremation. The text presents recommendations specifically addressing those issues.


Subject(s)
Brachytherapy , Prostatic Neoplasms/radiotherapy , Radiation Injuries/prevention & control , Radiation Protection , Adult , Brachytherapy/adverse effects , Brachytherapy/instrumentation , Brachytherapy/standards , Humans , Iodine Radioisotopes/therapeutic use , Iridium Radioisotopes/therapeutic use , Male , Palladium/therapeutic use , Radiation Injuries/etiology , Radioisotopes/therapeutic use , Radiotherapy Dosage
16.
Med Phys ; 29(7): 1562-71, 2002 Jul.
Article in English | MEDLINE | ID: mdl-12148739

ABSTRACT

The dose distribution around an intravascular brachytherapy 90Y line source with centering balloon catheters was measured with a plastic scintillator, TLD and radiochromic film. The absolute dose rates measured with the three detectors in a solid water phantom at 1, 2 and 3 mm distance from the centering balloon surfaces are in agreement within 3.5%, when the detectors are calibrated with the same 90Sr/90Y source. The dose rates measured with the plastic scintillator in the solid water phantom are in agreement with those directly measured in water. The measured relative dose distributions can be reproduced by Monte Carlo calculations. Also, the influence of the balloon diameter on the dose rate can be reproduced by the calculations. The dose rate calibration routinely performed with the plastic scintillator was checked for fifty-one sources with a well chamber and with another dedicated dose rate checking device. These measurements show that the consistency of the calibration of these sources was better than 10%. In a previous paper absolute dose rates for five other 90Y sources measured with TLD and radiochromic film in a solid water phantom were compared with those obtained with the plastic scintillator in water [Piessens and Reynaert, "Verification of absolute dose rates for intravascular beta sources," Phys. Med. Biol. 45, 2219-2231 (2000)]. Differences of 25 to 41%, depending on the balloon diameter, were reported. In this paper we show the evidence for three main reasons for these previously observed discrepancies: an inconsistency between a detector calibration performed with a 6 MeV electron beam and with a calibrated 90Sr/90Y source from NIST (16%), inaccuracies of the measuring distances in the solid water phantom (maximum 7.5%) and a time instability of the plastic scintillator, probably due to radiation damage (6%).


Subject(s)
Brachytherapy/methods , Brachytherapy/standards , Catheterization/methods , Radioisotopes/therapeutic use , Ytterbium/therapeutic use , Calibration , Humans , Models, Statistical , Monte Carlo Method , Phantoms, Imaging , Radiometry , Water , X-Ray Film
17.
Cardiovasc Radiat Med ; 3(3-4): 209-12, 2002.
Article in English | MEDLINE | ID: mdl-12974376

ABSTRACT

PURPOSE: Beta radiation has found increasing interest in intravascular brachytherapy for successfully overcoming the severe problem of restenosis after interventional treatment of arterial stenosis. Prior to initiating procedures applying beta radiation there is a common need to specify methods for the determination and specification of the absorbed dose to water or tissue and their spatial distributions. The DIN-NAR standardization in radiology task group Dosimetry has initiated an international ad hoc working group for an ISO new work item proposal on the standardization of procedures in clinical beta radiation dosimetry. METHODS: The intent of this standard is to review methods and to give recommendations for the calibration of therapeutic beta sources, a code of practice for clinical beta radiation dosimetry and guidance for estimating the uncertainty of the absorbed dose to water delivered. The standard will be confined to "scaled" radioactive sources such as single seeds, source trains, line, shell and volume sources for which only the beta radiation emitted is of therapeutic relevance. The topics will include dosimetric quantities; source data; calibration and traceability; general principles and requirements for absorbed dose measurements; in phantom dosimetry; theoretical modeling; presentation of dose distributions; clinical dosimetry; clinical quality control; irradiation treatment planning; as well as uncertainties. The document is geared to organizations wishing to establish reference methods in dosimetry aiming at clinical demands for appropriate small measurement uncertainties. Existing normative documents as well as international recommendations, such as those from AAPM, DGMP, ESTRO, NCS, ICRU, or IAEA will be taken into account. RESULTS: The first meetings of the new international working group took place in March and September 2002 at Essen, Germany [IAEA-cn-96-73, 2002]. CONCLUSIONS: Based on the DGMP Report 16, the AAPM TG 60 up-date draft, other recommendations and normative documents, the DIN-NAR project has collected and prepared detailed material on the calibration and dosimetry of beta radiation brachytherapy sources in terms of absorbed dose to water. The ISO new work item proposal will be completed in spring 2003.


Subject(s)
Beta Particles/therapeutic use , Brachytherapy/standards , Coronary Restenosis/radiotherapy , Practice Guidelines as Topic/standards , Practice Patterns, Physicians'/standards , Radiometry/standards , Water/pharmacology , Calibration/standards , Humans , Radiotherapy Dosage/standards
18.
Med Phys ; 28(8): 1776-85, 2001 Aug.
Article in English | MEDLINE | ID: mdl-11548949

ABSTRACT

In this work, we have calculated the two-dimensional dose distribution in water for a 32P intravascular brachytherapy source wire using the EGSnrc Monte Carlo code. The beta source (Guidant Vascular Intervention) has a radioactive core with a length of 27 mm and a diameter of 0.24 mm. The dose parameters required by the AAPM TG-60 formalism are discussed and calculated. Dose rate evaluated at the reference point is 0.1311+/-0.0001 Gy min(-1) mCi(-1). For the beta source studied, the dose distribution is uniform along the axial direction z for a given radial position p for - 10 mm< or =z< or =10 mm and p< or =7 mm. In such a dose-uniformity region, the dose field can be characterized by one-dimensional dose distribution, D(p), the dose distribution on the transverse axis. Beyond this region a two-dimensional (2D) description is necessary. However, for the long beta source wire the anisotropy function proposed by the TG-60 formalism becomes indefinable when the radial distance exceeds penetration depth of beta electrons. We have proposed that the anisotropy function be expressed in the cylindrical coordinate system, instead of a polar system, to remedy this deficiency. For practical purposes, the entire 2D dose distribution and the dose parameters calculated in the work are tabulated for ease of use.


Subject(s)
Brachytherapy/methods , Monte Carlo Method , Phosphorus Radioisotopes/therapeutic use , Anisotropy , Brachytherapy/standards , Electrons , Humans , Water
19.
Int J Radiat Oncol Biol Phys ; 49(4): 1033-43, 2001 Mar 15.
Article in English | MEDLINE | ID: mdl-11240245

ABSTRACT

PURPOSE: This report presents the American Brachytherapy Society (ABS) guidelines for the use of brachytherapy for patients with soft tissue sarcoma. METHODS AND MATERIALS: Members of the ABS with expertise in soft tissue sarcoma formulated brachytherapy guidelines based upon their clinical experience and a review of the literature. The Board of Directors of the ABS approved the final report. RESULTS: Brachytherapy used alone or in combination with external beam irradiation is an established means of safely providing adjuvant local treatment after resection for soft tissue sarcomas in adults and in children. Brachytherapy options include low dose rate techniques with iridium 192 or iodine 125, fractionated high dose rate brachytherapy, or intraoperative high dose rate therapy. Recommendations are made for patient selection, techniques, dose rates, and dosages. Complications and possible interventions to minimize their occurrence and severity are reviewed. CONCLUSION: Brachytherapy represents an effective means of enhancing the therapeutic ratio, offering both biologic and dosimetric advantage in the treatment of patients with soft tissue sarcoma. The treatment approach used depends upon the institution, physician expertise, and the clinical situation. Guidelines are established for the use of brachytherapy in the treatment of soft tissue sarcomas in adults and in children. Practitioners and cooperative groups are encouraged to use these guidelines to formulate their treatment and dose-reporting policies. These guidelines will be modified, as further clinical results become available.


Subject(s)
Brachytherapy/methods , Sarcoma/radiotherapy , Adult , Age Factors , Brachytherapy/standards , Child , Humans , Neoplasm Recurrence, Local/radiotherapy , Patient Selection , Radiography , Radiotherapy Dosage , Sarcoma/diagnostic imaging , Sarcoma/surgery
20.
Int J Radiat Oncol Biol Phys ; 48(3): 779-90, 2000 Oct 01.
Article in English | MEDLINE | ID: mdl-11020575

ABSTRACT

PURPOSE: To develop recommendations for use of high-dose-rate (HDR) brachytherapy in patients with endometrial cancer. METHODS: A panel of members of the American Brachytherapy Society (ABS) performed a literature review, supplemented their clinical experience, and formulated recommendations for endometrial HDR brachytherapy. RESULTS: The ABS endorses the National Comprehensive Cancer Network (NCCN) guidelines for indications for radiation therapy for patients with endometrial cancer and the guidelines on HDR quality assurance of the American Association on Physicists in Medicine (AAPM). The ABS made specific recommendations for HDR applicator selection, insertion techniques, target volume definition, dose fractionation, and specifications for postoperative adjuvant vaginal cuff therapy, for vaginal recurrences, and for medically inoperable primary endometrial cancer patients. The ABS recommends that applicator selection should be based on patient and target volume geometry. The dose prescription point should be clearly specified. The treatment plan should be optimized to conform to the target volume whenever possible while recognizing the limitations of computer optimization. Suggested doses were tabulated for treatment with HDR alone, and in combination with external beam radiation therapy (EBRT), when applicable. For intravaginal brachytherapy, the largest diameter applicator should be selected to ensure close mucosal apposition. Doses should be reported both at the vaginal surface and at 0.5-cm depth irrespective of the dose prescription point. For vaginal recurrences, intracavitary brachytherapy should be restricted to patients with nonbulky (< 0.5-cm thick) disease. Patients with bulky (> 0.5-cm thick) recurrences should be treated with interstitial techniques. For medically inoperable patients, an appropriate applicator that will allow adequate irradiation of the entire uterus should be selected. CONCLUSION: Recommendations are made for HDR brachytherapy for endometrial cancer. Practitioners and cooperative groups are encouraged to use these recommendations to formulate their treatment and dose reporting policies. This will lead to meaningful comparisons of reports from different institutions and lead to advances and appropriate use of HDR.


Subject(s)
Brachytherapy/standards , Carcinoma/radiotherapy , Endometrial Neoplasms/radiotherapy , Brachytherapy/instrumentation , Brachytherapy/methods , Female , Humans , Societies, Medical/standards , United States , Vaginal Neoplasms/radiotherapy , Vaginal Neoplasms/secondary
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