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J J Beitler

Publications and source records attributed to J J Beitler.

At least 19 recordsLinked to original sources
PubMed2002

Improved dose homogeneity in scalp irradiation using a single set-up point and different energy electron beams.

Homogeneous irradiation of the entire or a large portion of the superficial scalp poses both technical and dosimetric challenges. Some techniques will irradiate too much of the underlying normal brain while other techniques are either complex and involve field matching problems or may require sophisticated linear accelerator (linac) add-ons such as intensity modulated radiation therapy (IMRT)/electron multileaf collimation. However, many radiotherapy facilities are not equipped with such treatment modalities. We propose a practical treatment technique that can be delivered with a standard linac capable of producing high energy electrons. The proposed technique offers a simple alternative for achieving results equivalent to IMRT. Dose homogeneity throughout the treatment volume is achieved by aiming different energy electron beams at differential areas of the treatment surface to achieve improved dosimetry and rapid treatment delivery, while using a single set-up point. We introduced this treatment technique at our institution to treat superficial cancers of the scalp and other irregular surfaces.

Brachytherapy↗
PubMed2001

Methods of bolusing the tracheostomy stoma.

PURPOSE: The tracheostomy stoma is a potential site of recurrence for patients who have subglottic cancer or subglottic spread of cancer. In these patients, it is important that the anterior supraclavicular field does not underdose the posterior wall of the tracheostomy stoma when using a 6-MV anterior photon field. Conventionally, this problem is surmounted with placement of a plastic tracheostomy tube, which is uncomfortable for the patient, potentially traumatic, and can interfere with vocalization via a tracheal esophageal puncture. Our study was designed to investigate the dosimetry of this region and see if alternate methods would be effective. METHODS AND MATERIALS: A phantom was constructed using a No. 6 tracheostomy tube as the model for the tracheostomy curvature and size. Using the water-equivalent phantom, film dosimetry, and films oriented parallel to the en face field, we investigated the dose at the depth of the surface of the posterior wall of the phantom's tracheostomy stoma. Dose was measured both in space and at the tissue interface by scanning points of interest both horizontally and vertically. We measured doses with a No. 6 and No. 8 plastic tracheostomy tube, either 0.5 cm and 1.0 cm of bolus (1-cm airhole) with no tracheostomy tube, as well as 0.3 cm and 0.6 cm tissue-equivalent Aquaplast (Med-Tec Co., Orange City, Iowa) over the tracheostomy. Dosimetry at the posterior interface was confirmed using thermoluminescent dosimeters. RESULTS: Three mm and 6 mm of Aquaplast produced a posterior tracheal dose of 93% and 100%. CONCLUSION: There is no need for these patients to wear a temporary plastic tracheostomy tube during their external radiation therapy. Aquaplast should allow better position reproducibility, reduce trauma, not interfere with patient respiratory efforts, and be compatible with vocalization via a tracheal esophageal puncture.

Glottis↗
PubMed2001

Weekend warriors.

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Costs and Cost Analysis↗
PubMed2001

Stage 4 squamous cell carcinoma of the tongue in a child: complete response to chemoradiotherapy.

This report describes a complete response to a chemoradiotherapy regimen in a child with an advanced and unresectable squamous cell carcinoma of the tongue. An 8-year-old girl had stage 4 squamous cell carcinoma of the tongue (T4N2M0), causing severe trismus and dysphagia. She received hyperfractionated external beam radiotherapy (total 74.4 Gy) and concomitant intravenous infusion of hydroxyurea (0.313 mg/m2 per min) for 43 days. Grade 3 mucositis and myelosuppression were the main toxicities. There was marked symptomatic improvement, and the patient achieved a complete response. She is disease-free 24 months after treatment, and all the acute symptoms have resolved. The regimen was well tolerated with acceptable toxicity and led to a complete objective response. This regimen needs further evaluation to confirm its efficacy and to ascertain its long-term effects in children.

Adult↗
PubMed2000

The next generation.

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Dose Fractionation, Radiation↗
PubMed2000

Long-term swallowing problems after organ preservation therapy with concomitant radiation therapy and intravenous hydroxyurea: initial results.

OBJECTIVE: To evaluate the long-term effects on swallowing function of concomitant continuous infusion hydroxyurea and hyperfractionated radiation therapy used to treat advanced head and neck carcinoma. DESIGN: A prospective evaluation of swallowing function was performed on an inception cohort by analyzing posttreatment videoflouroscopic swallow function studies using radiological descriptors for pharyngeal transport abnormalities and temporal measures of structural movements, as well as by conducting patient interviews to assess alimentation, more than 1 year after tumor treatment (range, 52-124 weeks; median, 70 weeks). SETTING: Academic tertiary care referral medical center. PATIENTS: Ten patients, aged 44 to 71 years, with stage III and IV squamous cell carcinoma of the oral cavity, oropharynx, or hypopharynx. MAIN OUTCOME MEASURE: Radiographic and temporal swallow abnormalities, as well as functional status, were documented and compared with published norms and results of earlier swallowing studies when possible. RESULTS: Pharyngeal transport dysfunction and anterior segment abnormalities, manifested by epiglottic dysmotility, vallecular residue, laryngeal penetration, or aspiration, were evident in all 10 patients. Posterior segment abnormalities, such as pharyngeal stasis, constrictor dysmotility and piriform residue were documented in 8 patients. Three patients developed late aspiration, and the majority of patients showed persistent or worsened delay in laryngeal movement compared with their earlier posttreatment evaluations. Also, 3 patients developed a hypopharyngeal stricture, and 6 patients continued to require gastrostomy tube supplementation beyond 1 year. There was no association between site of primary, duration to swallowing evaluation, and severity of dysfunction. CONCLUSION: Prolonged and debilitating functional swallowing abnormalities may occur after this aggressive concomitant chemotherapy and radiotherapy regimen.

Adult↗
PubMed2000

Early wound complications in advanced head and neck cancer treated with surgery and Ir 192 brachytherapy.

OBJECTIVES: Brachytherapy, either as primary or adjuvant therapy, is increasingly used to treat head and neck cancer. Reports of complications from the use of brachytherapy as adjuvant therapy to surgical excision have been limited and primarily follow Iodine 125 (I125) therapy. Early complications include wound breakdown, infection, flap failure, and sepsis, and late complications may include osteoradionecrosis, bone marrow suppression, or carotid injuries. The authors sought to identify the early wound complications that follow adjuvant interstitial brachytherapy with iridium 192 (IrS92). STUDY DESIGN: A retrospective chart review of all patients receiving adjuvant brachytherapy at a tertiary medical center over a 4-year period. METHODS: Nine patients receiving Ir192 brachytherapy via afterloading catheters placed during surgical resection for close or microscopically positive margin control were evaluated. It was used during primary therapy in six patients and at salvage surgery in three. Early complications were defined as those occurring within 6 weeks of surgical therapy. RESULTS: The overall complication rate was 55% (5/9), and included significant wound breakdown in two patients, minor wound dehiscence in three, and wound infection, bacteremia, and local tissue erosion in one patient each. All complications occurred in patients receiving flap reconstruction and one patient required further surgery to manage the complication. Complication rates were not associated with patient age, site, prior radiotherapy, timing of therapy, number of catheters, or dosimetry. CONCLUSIONS: The relatively high complication rate is acceptable, given the minor nature of most and the potential benefit of radiotherapy. Further study should be undertaken to identify those patients who will achieve maximum therapeutic benefit without prohibitive local complications.

Aged↗
PubMed1999

Benign parotid hypertrophy on +HIV patients: limited late failures after external radiation.

PURPOSE: Although 8-10 Gy of external radiation therapy for +HIV associated parotid hypertrophy has achieved high response rates, the responses were transient with only 1/12 of patients retaining cosmetic control at median follow-up procedures of 9.5 months. Retreatment for failures after 8-10 Gy has also been unsatisfactory. Having shown that 24 Gy of external radiation therapy for benign parotid hypertrophy produced more durable cosmetic control than 8-10 Gy, we now report on longer follow-up periods on a group of patients receiving 24 Gy. MATERIALS AND METHODS: Twenty +HIV patients with clinical and radiographic evidence of lymphoepithelial lesions of the parotid were treated with 24 Gy of external radiation therapy using daily 1.5 Gy fractions; parallel opposed technique and 6 MV photons were used in 19 patients, and unilateral electron treatment was performed for one patient. RESULTS: With a mean follow-up period of 24 months, the cosmetic control appears durable. We have had no late failures past 24 months. Two patients have complained of modest xerostomia. There was no correlation with size of the cyst and eventual cosmetic result. CONCLUSIONS: Twenty-four Gy produces durable parotid control for HIV associated lymphoepithelial lesions of the parotid glands in +HIV patients. Failures after 2 years are uncommon and the side effects have been tolerable.

Female↗
PubMed1999

Chemoradiotherapy of locally advanced esophageal cancer: long-term follow-up of a prospective randomized trial (RTOG 85-01). Radiation Therapy Oncology Group.

CONTEXT: Carcinoma of the esophagus traditionally has been treated by surgery or radiation therapy (RT), but 5-year overall survival rates have been only 5% to 10%. We previously reported results of a study conducted from January 1986 to April 1990 of combined chemotherapy and RT vs RT alone when an interim analysis revealed significant benefit for combined therapy. OBJECTIVE: To report the long-term outcomes of a previously reported trial designed to determine if adding chemotherapy during RT improves the survival rate of patients with esophageal carcinoma. DESIGN: Randomized controlled trial conducted 1985 to 1990 with follow-up of at least 5 years, followed by a prospective cohort study conducted between May 1990 and April 1991. SETTING: Multi-institution participation, ranging from tertiary academic referral centers to general community practices. PATIENTS: Patients had squamous cell or adenocarcinoma of the esophagus, T1-3 N0-1 M0, adequate renal and bone marrow reserve, and a Karnofsky score of at least 50. Interventions Combined modality therapy (n = 134): 50 Gy in 25 fractions over 5 weeks, plus cisplatin intravenously on the first day of weeks 1, 5, 8, and 11, and fluorouracil, 1 g/m2 per day by continuous infusion on the first 4 days of weeks 1, 5, 8, and 11. In the randomized study, combined therapy was compared with RT only (n = 62): 64 Gy in 32 fractions over 6.4 weeks. MAIN OUTCOME MEASURES: Overall survival, patterns of failure, and toxic effects. RESULTS: Combined therapy significantly increased overall survival compared with RT alone. In the randomized part of the trial, at 5 years of follow-up the overall survival for combined therapy was 26% (95% confidence interval [CI], 15%-37%) compared with 0% following RT. In the succeeding nonrandomized part, combined therapy produced a 5-year overall survival of 14% (95% CI, 6%-23%). Persistence of disease (despite therapy) was the most common mode of treatment failure; however, it was less common in the groups receiving combined therapy (34/130 [26%]) than in the group treated with RT only (23/62 [37%]). Severe acute toxic effects also were greater in the combined therapy groups. There were no significant differences in severe late toxic effects between the groups. However, chemotherapy could be administered as planned in only 89 (68%) of 130 patients (10% had life-threatening toxic effects with combined therapy vs 2% in the RT only group). CONCLUSION: Combined therapy increases the survival of patients who have squamous cell or adenocarcinoma of the esophagus, T1-3 N0-1 M0, compared with RT alone.

Adenocarcinoma↗
PubMed1999

The relationship between dose heterogeneity ("hot" spots) and complications following high-dose rate brachytherapy.

PURPOSE: It is generally believed that "hot" spots should be avoided in radiotherapy because they lead to complications. Dose homogeneity within the target volume is much more difficult to achieve during brachytherapy than during external beam irradiation, and implants are rarely geometrically perfect. To not underdose some parts of the target volume, therefore, it may be necessary to accept hot spots in other parts of the target volumes, but it is not at all clear from the literature how much dose heterogeneity should be considered excessive. We undertook this study in an effort to determine just how high a dose to a hot spot is associated with clinically significant complications. METHODS AND MATERIALS: We studied 40 patients treated by high-dose rate brachytherapy with or without external irradiation. For each patient, we calculated the minimum dose to the "hottest" 1 cubic centimeter (cc) volume (Dmax1) and, for 18 patients, the minimum dose to the hottest 10 cc volume (Dmax10) as well. RESULTS: Considerable dose heterogeneity existed within the target volume. The Dmax1 ranged from 150-2000% (median 320%) of the minimum target dose (MTD). The median MTD/fraction was 2.50 Gy (range 1.50-25.00), and the median Dmax1/fraction was 10.00 Gy (range 3.75-150.00). The median Dmax1 from the entire course of brachytherapy was 75.00 Gy (range 25.00-550.00). Adding the doses from planned external irradiation, plus any prior irradiation to the same area, the median total Dmax1 was 112.50 Gy (range 30.00-580.00), yet the incidence of complications, even among those in the highest quartile of this dose range, was not greater than the lowest quartile. The total median Dmax10 was 85.00 Gy (range 32.00-130.00), but the incidence of complications was, again, similar whether the dose was in the lower or the upper half of this range (32.00-85.00 Gy, or 86.00-130.00 Gy, respectively). CONCLUSIONS: We had expected to find that the patients with the highest Dmax1 and/or Dmax10 would be the ones most likely to suffer complications, but the results did not support this hypothesis. Thus, dose heterogeneity, within the scope of our study, turned out to be rather unimportant with regard to complications. This finding contradicts the conventional wisdom and suggests that concerns about hot spots need not preclude optimization to ensure adequate dosage to all parts of the target volume.

Adult↗
PubMed1999

Pharyngeal transport dysfunction consequent to an organ-sparing protocol.

OBJECTIVE: To investigate the effects of a protocol of concomitant intravenous hydroxyurea and hyperfractionated, accelerated, external-beam radiation therapy on the swallowing mechanism of patients with advanced-stage head and neck cancer. DESIGN: Posttreatment videofluoroscopic swallow function studies, using images of single-bolus swallows of low-density liquid barium, were analyzed in real time, slow motion, and frame by frame using an integrated system that allows objective analysis of video recordings through image processing and digitization (Kay Elemetrics Computerized Swallowing Station). Radiological descriptors were used for pharyngeal transport abnormalities, and temporal measures were obtained of structural movements. SETTING: Academic, tertiary care, referral medical center. PATIENTS: Fifteen consecutive patients with previously untreated, stages III and IV, nonmetastatic squamous cell carcinoma of the head and neck who underwent a phase 1 study of prolonged infusion hydroxyurea therapy in combination with hyperfractionated, accelerated external-beam radiation therapy for their disease. RESULTS: All patients had anterior pharyngeal segment dysfunction, characterized by no epiglottic movement and slowed laryngeal motility (1.011 +/- 0.379 seconds [mean +/- SD). Anterior pharyngeal dysfunction was more severe in patients with primary tumors of the hypopharynx than in those with cancer of the oropharynx. Twelve (80%) of our patients demonstrated posterior pharyngeal segment dysfunction characterized by impaired pharyngeal constrictor motility. All 15 patients displayed pharyngeal stage abnormalities that limited bolus transport and clearance. CONCLUSIONS: Severe pharyngeal physiological abnormalities were present that led to impaired bolus transport and that were frequent and debilitating consequences of this organ-sparing protocol. Long-term follow-up of this group will be required to assess the permanence of the abnormalities.

Adult↗