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J E Bellotti

Publications and source records attributed to J E Bellotti.

5 recordsLinked to original sources
PubMed1993

Intracavitary radiation in the treatment of advanced esophageal carcinoma: a comparison of high dose rate vs. low dose rate brachytherapy.

Twenty-two patients were irradiated using two different dose schedules of intracavitary irradiation for palliation of locally advanced or metastatic carcinoma of the esophagus. Irradiation was given solely with either manually afterloaded low/intermediate dose Cesium-137 (LDR) or high dose rate Iridium-192 (HDR) delivered via remote afterloader. This study was designed to test the effectiveness of HDR intracavitary brachytherapy in the relief of dysphagia and the maintenance of esophageal patency and to compare with our previous experiences with LDR intracavitary brachytherapy. Accelerated treatments were especially suited for patients with poor physical condition or short life expectancy unlikely to complete a full course of external beam irradiation without treatment interruption. Two thousand cGY in three fractions of LDR was compared with 1,250 cGY in one fraction HDR with essentially equal results.

Brachytherapy↗
PubMed1993

Application of the ICRU Report 38 reference volume concept to the radiotherapeutic management of recurrent endometrial and cervical carcinoma.

Radiation therapy was given to 25 patients presenting with pelvic recurrence of endometrial (14) and cervical (11) cancer. Of these patients, all but one had undergone hysterectomy following their original diagnosis. Two endometrial patients received preoperative intracavitary irradiation. The recurrence-free interval ranged from 5 to 71 months (mean = 21 months). External beam radiation therapy for pelvic recurrence ranged from 3000 to 5000 cGy. Additional central radiation was given to 18 patients with either external beam, intracavitary, interstitial, or transvaginal technique. Dose and dose rates from brachytherapy are documented with maximum values, along with the location of these dose points. Such specification is essential in obtaining a more accurate impression of the total dose delivered to the patient, especially when different techniques are employed to increase the dose to the center of the pelvis. Reference volume dimensions, similar to those specified by ICRU Report 38 for intracavitary treatments, are presented. Mean follow-up from completion to radiotherapy is 22 months; 16 patients are dead, 2 are alive with disease, and 7 are alive with no evidence of disease.

Adult↗
PubMed1990

Effective palliation for inoperable esophageal cancer using intensive intracavitary radiation.

In a pilot study between May 1988 and May 1989, ten consecutive patients with advanced esophageal cancer were treated with a short intensive course of intraluminal curietherapy without external beam irradiation at the Kaiser Permanente-Los Angeles Medical Center. Nine of ten patients achieved effective palliation comparable to that of standard external beam teletherapy from other series. Most patients had already failed other palliative modalities including chemotherapy, laser debridement, dilation, and electrocautery. The duration of response was generally longer than with these techniques. All patients completed therapy, and tolerance was excellent. Intraluminal irradiation is an attractive, effectual therapeutic alternative, especially in patients with advanced local or distant disease unlikely to tolerate 5 to 7 weeks of external beam therapy.

Aged↗
PubMedDate not supplied

Conversion from Cs-137 to Ir-192 for high dose rate remote afterloading: practical considerations.

High dose rate (HDR) remote afterloading is increasingly being used to replace many conventional low dose rate (LDR) brachytherapy procedures. Implementation of the microSelectron-HDR with Ir-192 at our facility necessitated this study to obtain equivalent dosimetric distributions with those of our LDR Cs-137 techniques using our current treatment planning system. Three anatomical sites are presented: nasopharynx, esophagus, and uterine cervix. Attention must be given to the anisotropy of Cs-137 tubes when converting to Ir-192; for linear geometries, total equivalent activity may be preserved but the shapes of the resulting isodose curves for Ir-192 are longer than those of Cs-137. In the case of Fletcher-Suit intracavitary treatments of the uterine cervix, the longer contours for Ir-192 in the vaginal ovoids results in higher isodose levels reaching the bladder and rectum. Maintaining the traditional dose levels to these organs is accomplished by modifying the loading of the ovoids to approximately 85% of the corresponding Cs-137 activity. Computerized dosimetry is presented, along with a chart we have devised to easily convert a standard LDR treatment to HDR dwell times. Our results are especially suitable to those users who will continue to make use of their present computer treatment planning system.

Brachytherapy↗