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J Blasko

Publications and source records attributed to J Blasko.

At least 19 recordsLinked to original sources

Clinical staging of prostate cancer: reproducibility and clarification of issues.

The American Joint Committee on Cancer (AJCC) staging system for prostate cancer adopted in 1992 is based on tumor-node-metastasis (TNM) designations. It has been widely accepted for use in local and advanced disease. The purpose of this study was to assess reproducibility of staging among observers and to help clarify staging issues. Twelve prostate cancer cases were sent to 20 physicians with special expertise in prostate cancer including eight urologists, eight radiation oncologists, and four medical oncologists. Physicians were asked to assign a stage based on the 1992 AJCC clinical staging. The most frequently reported stage assigned to each case was taken to be the consensus. Agreement was the percentage of physicians who reported that particular stage. Seventy-five percent of the physicians responded. The overall agreement for assignment of T stage was 63.9%. Differences were found by specialty for inclusion of available information in designating a T stage. The overall agreement for N stage was 73.8%. The most common designation was Nx regardless of availability of a computed tomography scan. The overall agreement for M stage was 76.6%. Without a bone scan the most common designation was Mx regardless of Gleason grade or prostate-specific antigen (PSA). A frequent comment was that PSA was more indicative of disease extent than current clinical staging. The reproducibility of the 1992 clinical AJCC staging is poor even among experts in the field. This problem arises primarily from disagreement regarding which studies are included in assigning a stage. Some of these difficulties are addressed in the 1997 revision. However, the clinical staging does not address the true biological significance of disease in many instances.

Humans↗

Transperineal brachytherapy in patients with large prostate glands.

The purpose of this study is to help clarify the use of prostate size as a selection factor for prostate brachytherapy. From 1997 to 1998, 33 patients with a TRUS-based prostate volume greater than 50 cc were treated at the University of Washington by I-125 (144 Gy) or Pd-103 (115 Gy) implantation for prostatic carcinoma. These 33 patients comprised 7% of the total implants performed. Each patient underwent a preimplant TRUS study in the lithotomy position, taking serial axial images of the prostate at 0.5 cm intervals from the base of the gland to the apex. The contours on the preimplant TRUS images were used to calculate the prostate volumes reported here. Only one patient received supplemental external beam irradiation prior to implantation. Twelve patients were treated with neoadjuvant androgen ablation prior to implantation. The prostate volumes quoted here are those taken after hormonal downsizing. Postimplant axial CT images were digitized to calculate the CT-based target coverage. Preimplant urinary obstructive symptoms were quantified by the criteria of the American Urologic Association. Each patient was contacted at the time of this article preparation to update postimplant morbidity information. In all cases, at least 80% of the postimplant volume was covered, despite a median implant-related volume increase of 15%. Five of the 33 patients' postimplant CT scans showed some degree of incomplete target coverage of the anterior/lateral prostate margin. There was no clear association between inadequate anterior/lateral coverage and the degree of interference. Twelve of the 33 patients developed acute postimplant urinary retention, all occurring within 24 hr of implantation. Within this group of 33 patients with a large prostate volume, there was no relationship between the likelihood of acute or chronic urinary retention and preimplant prostate size or obstructive symptoms. Patients who developed postimplant retention lasting more than one week were generally managed by intermittent self-catheterization. By one month, 85% of patients were catheter-free. Based on the data reported here, we are more inclined to accept patients with a large prostate for implantation without insisting on preimplant size reduction. Int. J. Cancer (Radiat. Oncol. Invest.) 90, 199-205 (2000).

Brachytherapy↗

American brachytherapy society recommendations for clinical implementation of NIST-1999 standards for (103)palladium brachytherapy. The clinical research committee of the American Brachytherapy Society.

PURPOSE: Recent important developments in palladium-103 ((103)Pd) dosimetry mandate a reevaluation of (103)Pd brachytherapy prescribing practices. METHODS AND MATERIALS: The clinical research committee of the American Brachytherapy Society (ABS) convened a consensus session of brachytherapists and physicists to develop recommendations regarding future dose prescribing guidelines for National Institute of Standards and Technology (NIST-1999) calibrated (103)Pd sources. RESULTS: The ABS recommends that clinicians attempt to reproduce the implant doses delivered and reported in the literature through the past decade. CONCLUSIONS: The following should be immediately implemented for (103)Pd dosimetry: 1) All practicing physicians, physicists, dosimetrists, and suppliers implement NIST-1999 air-kerma strength standard for (103)Pd brachytherapy. 2) All treatment planning systems and dose calculation algorithms must be updated to reflect new dose rate constants. The AAPM-recommended validated value for Theraseed model 200 is 0.665 cGy h(-1) U(-1). The dose rate constant for the Mentor MED3633 seed is currently reported as 0.68 cGy h(-1) U(-1). This latter value and the values for seeds from other manufacturers are awaiting independent confirmation. 3) Physicians who previously prescribed 115 Gy for (103)Pd monotherapy prostate implants should now prescribe 125 Gy. When using (103)Pd as a boost following 45 Gy of external beam irradiation, 100 Gy should be prescribed instead of the previous 90 Gy. It is critical that all three changes be implemented concurrently, because they are interdependent.

Brachytherapy↗

Brachytherapy in patients with small prostate glands.

PURPOSE: To better define the role of small prostate volume in selecting patients for brachytherapy. MATERIALS AND METHODS: Thirty patients with a transrectal ultrasound (TRUS)-based prostate volumes less than 20 cc were treated at the University of Washington by permanent isotope implantation for prostatic carcinoma. Preimplant TRUS studies were taken at 0.5-cm intervals from the base of the gland to the apex. Planning margins of 1 to 5 mm were added to the prostatic margins, and sources were routinely planned to be placed as much as 5 mm outside of the prostatic margin. The prescription dose was 144 and 115 Gy for full-dose iodine 125 and palladium 103 monotherapy, respectively. For patients receiving supplemental external-beam irradiation, the implant doses were 120 and 90 Gy for 125I and 103Pd, respectively. The morning following the implant, axial computed tomographic (CT) images of the prostate were obtained at 0.5-cm intervals with patients in the supine position. Follow-up ranged from 11 to 28 months (median 21 months). RESULTS: The median coverage of the postimplant prostate volume by the prescription dose was 92%. To calculate the incidence of source migration, the number of sources placed at the time of implant was compared with the number identified on postimplant CT scan. The median number of sources implanted was 84 (range 65-103) compared to an average of 82 identified postoperatively, which is consistent with a source migration rate of two. A median of 31 sources appeared to be outside of the prostatic margins, as identified on postimplant CT scan (range 14-53). Of the 23 patients contacted at the time of this report, one had developed acute postimplant urinary retention that resolved within 2 weeks of implantation. At last follow-up, patient pre- and postimplant AUA scores were not substantially different, with the median AUA score increasing from 7 (range 2-21) to 8 (range 1-27). CONCLUSIONS: Patients with small prostate volumes appear to have acceptable morbidity and target coverage with prostate brachytherapy. Based on the data reported here, we do not believe that a small prostate volume in itself is a contraindication to brachytherapy.

Brachytherapy↗

Prostate brachytherapy in patients with prior evidence of prostatitis.

PURPOSE: To refute a misconception that a prior history of prostatitis is a contraindication to prostate brachytherapy. METHODS AND MATERIALS: Five patients with clinical or pathologic evidence of prior prostatitis were treated with transperineal brachytherapy. Four of the patients received a single i.v. dose of ciprofloxacin (500 mg) intraoperatively. Postimplant antibiotics were not given. The pretreatment biopsy slides were reviewed. RESULTS: Two of the five patients developed postimplant urinary retention requiring short-term catheterization, and both resolved spontaneously. One patient developed what appeared to be an exacerbation of his chronic prostatitis. CONCLUSION: We continue to recommend prostate brachytherapy for the treatment of clinically organ-confined cancer, with no concern about prior clinical or pathologic evidence of prostatitis.

Aged↗

Radiation safety parameters following prostate brachytherapy.

PURPOSE: To determine the degree and variability of radiation exposure to the general public from patients after I-125 or Pd-103 prostate brachytherapy. METHODS AND MATERIALS: Radiation exposure measurements were made from 38 consecutive, unselected patients with stage T1 or T2 prostatic carcinoma who had transperineal I-125 or Pd-103 implants at the University of Washington in 1998. RESULTS: The exposure rate at the anterior skin surface following a I-125 implant ranged from 2.2 to 8.9 mrem/hour (average: 5.0). The exposure rate at the anterior skin surface from a Pd-103 implant ranged from 0.5 to 4.9 mrem/hour (average: 1.7). Based on the current Nuclear Regulatory Commission (NRC) regulations the time required to reach the annual limit at the anterior skin surface would be 20 hours for I-125 and 59 hours for Pd-103. For exposure at the lateral skin surface, the times would exceed 500 hours for either isotope. CONCLUSIONS: This data suggest that patients need not be concerned about being a radiation risk to the general public following their procedure.

Brachytherapy↗

Use of TRUS to predict pubic arch interference of prostate brachytherapy.

PURPOSE: To demonstrate the potential for transrectal ultrasound (TRUS) to predict pubic arch interference of transperineal needle placement for prostate brachytherapy. METHODS AND MATERIALS: TRUS and pelvic computerized tomography (CT) scans from 22 patients who had transperineal prostate brachytherapy at University of Washington were analyzed for pubic arch visualization and interference. The outer margins of the prostate and the inner margins of the pubic bones from each imaging modality were outlined and compared. RESULTS: The pubic arch was readily visualized by TRUS in 21 of the 22 patients. There was good correlation between TRUS and CT for evaluating the amount of pubic arch interference (r = 0.90). CONCLUSION: TRUS can be substituted for CT imaging to evaluate pubic arch interference of transperineal needle placement for prostate brachytherapy. Eliminating routine CT scanning would reduce the cost of treatment.

Brachytherapy↗

Use of pelvic CT scanning to evaluate pubic arch interference of transperineal prostate brachytherapy.

PURPOSE: To determine the necessity of preoperative evaluation of pubic arch interference in patients with small prostate volumes. METHODS AND MATERIALS: CT scans from 97 consecutive, unselected patients with stage T1 or T2 prostatic carcinoma who had transperineal I-125 or Pd-103 implants at the University of Washington in 1997 were analyzed for pubic arch interference. Transrectal ultrasound (TRUS) was performed with 6.0-MHz transducer with the patient in the lithotomy position and the patient's thighs vertical, similar to that used during the implant procedure. CT scans were obtained with the patient in the supine position, with 0.5-cm images taken at every 0.5 cm. To check for potential arch interference, the largest prostate cross-section was overlaid on the narrowest portion of the pubic arch. The overlap of the pubic arch and the prostate margin is measured at right angles to the inner pubic surface. The prostate volume obtained from the TRUS images was compared with the degree of pubic arch interference in order to determine whether TRUS volume predicted for interference. RESULTS: There was considerable variability in pubic arch interference between patients. The mm of pubic arch overlap with the prostatic margin varied from -11 mm to 20 mm. Patients with larger prostate volumes generally had more pubic arch interference, but the degree of interference was only loosely related to the prostate volume (r = 0.46). CONCLUSIONS: The degree of pubic arch interference is highly variable from one patient to the next and the TRUS volume cannot reliably predict patients who do or do not need a pelvic CT to detect potential arch interference.

Brachytherapy↗

Comparability of CT-based and TRUS-based prostate volumes.

PURPOSE: To compare the prostate volumes defined by transrectal ultrasound (TRUS) versus computed tomographic (CT) scans used for brachytherapy planning. METHODS AND MATERIALS: Ten unselected patients underwent evaluation for prostate brachytherapy with TRUS and CT imaging. Axial prostate contours were obtained at 5-mm intervals in both studies. The CT images were photographed, scanned into a commercial software program, and reprinted from a laser printer at 600 dots per inch to provide individual images that were interpreted independently by the three physician authors (BK, KW, and JB). An effort was made to exclude pelvic floor muscles from the defined prostate contour. Volumes were calculated in cubic centimeters. The prostate volume and maximum dimension in each plane were compared for each imaging modality. RESULTS: The CT-based prostate volumes ranged from 31.1 cc to 48.1 cc. The TRUS-based volumes ranged from 26.6 cc to 46.4 cc. There was close agreement between imaging modalities (r = 0.9). The anterior-posterior, lateral, and craniocaudal prostatic dimensions were similar between modalities. To test for consistency between observers, the CT volumes were drawn independently by KB, KW, and JB. The prostatic measurements were consistent in all dimensions between observers. CONCLUSION: CT scan volumes and measurements correlate well with those obtained by TRUS, and are appropriate for pre- or postimplant dosimetry.

Brachytherapy↗

Anticipating prostatic volume changes due to prostate brachytherapy.

The purpose of the study was to determine which clinical parameters might predict individual prostate volume changes from prostate brachytherapy. Fifty consecutive, unselected patients treated at the University of Washington by I-125 or Pd-103 implantation for prostatic carcinoma in 1998 were analyzed. The prostate contours on preimplant transrectal ultrasound (TRUS) images were digitized and the prostate volumes calculated. Postimplant axial CT images of the prostate was obtained at 0.5 cm intervals with patients in the supine position the morning after the implant. The postimplant prostate volume increased by an average factor of 1.7 (+/-0.34) compared with the preimplant volume, the size increase being primarily in the anterior-posterior dimension. The absolute volume change was similar in patients with small vs. large preimplant prostate volume (r = -0.39), but the proportional change was less in patients with a larger prostate volume (r = -0.71). Because patients with a small preimplant prostate had proportionately greater volume increase, their postimplant target coverage was generally less. No single parameter, including preimplant prostate volume, preimplant hormonal deprivation, or supplemental external beam radiation therapy (EBRT) can accurately predict the degree of swelling. The precise significance of and practical solution to implant-related prostate volume changes remains to be determined.

Brachytherapy↗

Stereotactic radiosurgery toxicity in the treatment of intracanalicular acoustic neuromas: the Seattle Northwest gamma knife experience.

Patients with acoustic neuromas have several treatment options. The appropriate individual treatment decision and expected control rates and risks for the individual techniques have been outlined in several texts [1-4, 6-8]. This article describes radiosurgery toxicity in those patients with acoustic neuromas who have intracanalicular disease. 52 patients with 54 acoustic neuromas were treated between September 1993 and April 1997. 14 tumors were intracanalicular lesions, with a mean diameter <1 cm and volume <1 cm3. Dose to the periphery of the intracanalicular lesion extension ranged from 12-18 Gy (mean 16 Gy). The margin isodose was 40-60% (mean 47%). 32 isocenters were used to treat the 14 intracanalicular tumors (mean 2.3 isocenters per patient). At a mean follow-up of 18 months (range 1-39 months), 12/12 or 100% of the intracanalicular lesions demonstrated regression or no change in size on subsequent imaging. The following acute side effects were observed posttreatment in intracanalicular tumors: diminished hearing 14%, facial neuropathy 43%, trigeminal neuropathy 21%, balance disorder 14%, dizziness 7%, and headache 7%. Facial and trigeminal neuropathy, balance disorder, dizziness, vertigo and headaches were more common in patients with intracanalicular tumors than those with an extracanalicular extension. Although it has been suggested that small acoustic neuromas (i.e. <1 cm3) tolerate doses of 18 Gy with acceptable toxicity, when the lesion is located in the auditory canal a lesser dose may be warranted to minimize potential side effects. For now, our center has established a protocol that limits radiosurgical stereotactic intracanalicular peripheral doses to 12 Gy until further toxicity studies have been collected and reviewed.

Cranial Nerve Diseases↗

Gamma knife radiosurgery as a lesioning technique in movement disorder surgery.

OBJECT: To increase knowledge of the safety and efficacy of the use of gamma knife radiosurgery in patients with movement disorders, the authors describe their own experience in this field and include blinded independent assessments of their results. METHODS: Fifty-five patients underwent radiosurgical placement of lesions either in the thalamus (27 patients) or globus pallidus (28 patients) for treatment of movement disorders. Patients were evaluated pre- and postoperatively by a team of observers skilled in the assessment of gait and movement disorders who were blinded to the procedure performed. The observers were not associated with the surgical team and concomitantly and blindly also assessed a group of 11 control patients with Parkinson's disease who did not undergo any surgical procedures. All stereotactic lesions were made with the Leksell gamma unit using the 4-mm secondary collimator helmet and a single isocenter with maximum doses from 120 to 160 Gy. Clinical follow-up evaluation indicated that 88% of patients who underwent thalamotomy became tremor free or nearly tremor free. Statistically significant improvements in performance were noted in the independent assessments of Unified Parkinson's Disease Rating Scale (UPDRS) scores in the patients undergoing thalamotomy. Of patients undergoing pallidotomy who had exhibited levodopainduced dyskinesias, 85.7% had total or near-total relief of that symptom. Clinical assessment indicated improvements in bradykinesia and rigidity in 64.3% of patients who underwent pallidotomy. Independent blinded assessments did not reveal statistically significant improvements in Hoehn and Yahr scores or UPDRS scores. On the other hand, 64.7% of patients showed improvements in subscores of the UPDRS, including activities of daily living (58%), total contralateral score (58%), and contralateral motor scores (47%). Total ipsilateral score and ipsilateral motor scores were both improved in 59% of patients. One (1.8%) of 55 patients experienced a homonymous hemianopsia 9 months after pallidotomy due to an unexpectedly large lesion. No other complications of any kind were seen. Neuropsychological test scores that were obtained for the combined pallidotomy and thalamotomy treatment groups preoperatively and at 6 months postoperatively demonstrated an absence of cognitive morbidity. Follow-up neuroimaging confirmed correct lesion location in all patients, with a mean maximum deviation from the planned target of 1 mm in the vertical axis. Measurements of lesions at regular intervals on postoperative magnetic resonance images demonstrated considerable variability in lesion volumes. The safety and efficacy of functional lesions made with the gamma knife appear to be similar to those made with the assistance of electrophysiological guidance with open functional stereotactic procedures. CONCLUSIONS: Functional lesions may be made safely and accurately using gamma knife radiosurgical techniques. The efficacy is equivalent to that reported for open techniques that use radiofrequency lesioning methods with electrophysiological guidance. Complications are very infrequent with the radiosurgical method. The use of functional radiosurgical lesioning to treat movement disorders is particularly attractive in older patients and in those with major systemic diseases or coagulopathies; its use in the general movement disorder population seems reasonable as well.

Activities of Daily Living↗

Gamma knife radiosurgery as a lesioning technique in movement disorder surgery.

Fifty-five patients underwent radiosurgical placement of lesions either in the thalamus (27 patients) or globus pallidus (28 patients) for treatment of movement disorders. Patients were evaluated pre- and postoperatively by a team of observers skilled in the assessment of gait and movement disorders who were blinded to the procedure performed. They were not associated with the surgical team and concomitantly and blindly also assessed a group of 11 control patients with Parkinson's disease who did not undergo any surgical procedures. All stereotactic lesions were made with the Leksell gamma unit using the 4-mm secondary collimator helmet and a single isocenter with dose maximums from 120 to 160 Gy. Clinical follow-up evaluation indicated that 88% of patients who underwent thalamotomy became tremor free or nearly tremor free. Statistically significant improvements in performance were noted in the independent assessments of Unified Parkinson's Disease Rating Scale (UPDRS) scores in the patients undergoing thalamotomy. Eighty-five and seven-tenths percent of patients undergoing pallidotomy who had exhibited levodopa-induced dyskinesias had total or near-total relief of that symptom. Clinical assessment indicated improvement of bradykinesia and rigidity in 64.3% of patients who underwent pallidotomy. Independent blinded assessments did not reveal statistically significant improvements in Hoehn and Yahr scores or UPDRS scores. On the other hand, 64.7% of patients showed improvements in subscores of the UPDRS, including activities of daily living (58%), total contralateral score (58%), and contralateral motor scores (47%). Ipsilateral total UPDRS and ipsilateral motor scores were both improved in 59% of patients. One (1.8%) of 55 patients experienced a homonymous hemianopsia 9 months after pallidotomy due to an unexpectedly large lesion. No other complications of any kind were seen. Follow-up neuroimaging confirmed correct lesion location in all patients, with a mean maximum deviation from the planned target of 1 mm in the vertical axis. Measurements of lesions at regular interals on postoperative magnetic resonance images demonstrated considerable variability in lesion volumes. The safety and efficacy of functional lesions made with the gamma knife appear to be similar to those made with the assistance of electrophysiological guidance with open functional stereotactic procedures. Functional lesions may be made safely and accurately using gamma knife radiosurgical techniques. The efficacy is equivalent to that reported for open techniques that use radiofrequency lesioning methods with electrophysiological guidance. Complications are very infrequent with the radiosurgical method. The use of functional radiosurgical lesioning to treat movement disorders is particularly attractive in older patients and those with major systemic diseases or coagulopathies; its use in the general movement disorder population seems reasonable as well.

Journal Article↗

A method for implementing the American Association of Physicists in Medicine Task Group-43 dosimetry recommendations for 125I transperineal prostate seed implants on commercial treatment planning systems.

PURPOSE: To present our experience implementing the American Association of Physicists in Medicine (AAPM) Task Group #43 (TG-43) recommendations for 125I dosimetry parameters utilizing two commercially available treatment planning systems. METHODS AND MATERIALS: Single seed point source calculations were performed on two treatment planning systems and intercomparisons were conducted between known points of interest for (a) previously published data on each system, (b) TG-43 data on each system, and (c) hand calculations. Additional calculations and intercomparisons were performed for a typical 35 cm3 prostate volume implant with a prescribed dose of 160 Gy. RESULTS: Intercomparisons of calculations for single seed point source approximations with previously published data and TG-43 data indicated good agreement between the two systems at a distance of 1 cm. Point source comparisons between previously published data and TG-43 recommendations show a difference in dose of 11% to the 1 cm point. Calculations for a 35 cm3 permanent interstitial prostate implant showed the 160 Gy isodose line pulled centrally toward the seeds 1-2 mm as a result of the 11% change. CONCLUSIONS: It is advisable for physicians, physicists, and dosimetrists to exercise caution when incorporating the TG-43 recommendations for 125I into treatment planning systems. The effects caused by differences in dosimetry parameters need to be understood and accounted for when matching prescribed doses in order to ensure continuity of treatment and clinical results as reported in the current literature.

Humans↗

Gamma Knife radiosurgery for treatment of trigeminal neuralgia: idiopathic and tumor related.

Sixty patients with trigeminal neuralgia who did not have a response to pharmacologic treatment (including 22 who had no response to conventional surgical treatment) underwent stereotactic radiosurgical treatment with the Leksell Gamma Knife. A radiosurgical maximum dose of 70 Gy was delivered to the trigeminal nerve root adjacent to the pons via a 4-mm collimator helmet in 51 patients who presented with trigeminal neuralgia unrelated to tumors. In these patients, the root was localized by stereotactic MRI. Follow-up assessment of pain relief was accomplished by a third party not involved in the patients' clinical care. Within a latency period of 1 day to 4 months following the treatment, 38 of 51 patients (74.5%) were completely free of pain and eventually all medications were tapered off. An additional seven patients (13.7%) experienced reductions in pain from 50 to 90% and utilized little or no medications. Patients who had no prior surgical intervention fared much better than those who had previous surgery to relieve their facial pains. At last follow-up, a mean of 16.3 months (range 6-36 months) after treatment, 41 patients (80.4%) remained pain-free or had marked pain reduction. There were four patients with recurrent pain. All 26 patients with classical symptoms of trigeminal neuralgia with no atypical features who had no prior surgery, had complete or nearly complete pain relief, and none of these patients had recurrent pain. Nine patients with trigeminal neuralgia due to tumors received standard radiosurgical treatment directed at their tumors, and eight of nine (88.8%) had pain relief. Of the total of 60 patients treated for trigeminal neuralgia, 49 (81.7%) experienced complete or nearly complete relief of pain at last follow-up. Only one patient with pre-existing facial sensory loss due to a tumor had a mild increase in facial numbness. No other patient experienced either loss of facial sensation or any other complication. Gamma Knife radiosurgery appears to be a minimally invasive, safe, and effective therapy of trigeminal neuralgia.

Adult↗

Survey of brachytherapy practice in the United States: a report of the Clinical Research Committee of the American Endocurietherapy Society.

PURPOSE: To obtain reliable data on the extent of the brachytherapy practice in the United States by conducting a comprehensive survey of all facilities. METHODS AND MATERIALS: The Clinical Research Committee of the AES surveyed all 1321 radiation oncology facilities identified in the Patterns of Care Study (PCS) of the American College of Radiology (ACR). Multiple mailings and follow-up were made to obtain a high response rate. Survey responders and nonresponders were compared using chi-square tests. Summary statistics were reported. RESULTS: Of the 1321 facilities, 1054 responded (80%). Hospital-based and larger facilities had a statistically significant higher rate of response. Brachytherapy was being performed at 819 facilities (the median number of procedures = 21-50). Two hundred and two facilities did no brachytherapy. The common isotopes used were 137Cs (705 facilities), 192Ir (585 facilities), 125I (236 facilities), and 131I (194 facilities). The common brachytherapy techniques used were intracavitary (751 facilities), interstitial (536 facilities), intraluminal (310 facilities), and plaques (148 facilities). Remote afterloaded brachytherapy was used at 205 centers as follows: high dose rate (HDR) (164), medium dose rate (MDR) (5), and low dose rate (LDR) (36). Computerized dosimetry was most commonly used (790 facilities), followed by Patterson-Parker (104 facilities) and Quimby (72 facilities). The common sites treated were cervix (701 facilities), endometrium (565 facilities), head and neck (354 facilities), and lung (344 facilities). CONCLUSION: Data regarding brachytherapy practice has been obtained from a large percentage (80%) of all facilities in the United States. The majority (78-81%) of radiation oncology facilities perform brachytherapy; however, its use is restricted to gynecological implants in many of these centers. The results from this survey will be used to develop a pattern of care study and data registry in brachytherapy.

Brachytherapy↗