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R R Dobelbower

Publications and source records attributed to R R Dobelbower.

61 records · Page 4Linked to original sources
PubMedDate not supplied

Adjuvant radiotherapy with selective sandwich technique in treatment of rectal cancer: results of a continuing study.

Sixty-two patients with carcinoma of the rectum were treated with "selective sandwich" adjuvant radiotherapy in a pilot study which began in September 1976 at Thomas Jefferson University Hospital. All patients received 500 rads preoperative irradiation on the day of or day preceding surgery. Following surgery, the lesions were staged pathologically according to Astler-Coller's modification of Dukes' staging. Patients with poor prognostic characteristics (Stages B2, C1, and C2) were treated with aggressive postoperative pelvic irradiation (4500 rads in five weeks). All 62 patients received the single preoperative dose of 500 rads. Forty-four patients underwent abdominoperineal resection, four patients, a low anterior resection, ten patients, a combined abdominotranssacral resection, and four patients found to have liver metastasis at laparotomy had colostomy followed by palliative therapy. Twenty-one patients found to have early disease (Stages A or B1) were given no further therapy. Of 37 patients with Stages B2 or C disease, 21 received postoperative irradiation. Follow-up ranged from 6 months to 36 months, with a median of 18 months. Of patients with Stage A or B1 disease, one patient has died with metastasis. Two of 21 patients receiving postoperative irradiation have developed metastatic disease; neither has failed in the pelvis. Of 16 patients who did not receive postoperative irradiation, three have had metastasis to the pelvis and two others have developed distant metastasis.

Follow-Up Studies↗
PubMedDate not supplied

Radiation contamination and leakage assessment of intraoperative electron applicators.

In intraoperative radiation therapy, it is critical to reduce the radiation contamination outside the useful field by as much as physically feasible. Additionally, a uniform dose is clinically desirable across the tumor volume. A study of the Medical College of Ohio applicators indicates that the radiation contamination outside the field can be as high as 18% of the central axis dose. The effects of the photon collimator setting on the magnitude and energy of the radiation contamination are discussed and means are presented for reducing this unwanted radiation. The dose nonuniformity across the field is found to be virtually independent of the photon collimator setting and is shown to be mostly due to the transparent applicator wall. The clinical significance of the findings is discussed.

Combined Modality Therapy↗
PubMedDate not supplied

Radiation oncology practice accreditation.

The practice accreditation program of The American College of Radiology is described. Practice accreditation constitutes a facile mechanism to accomplish external quality assurance and to assess compliance with recognized standards. The process of accreditation includes critical review of each radiation therapy facility, the technical staff, all quality assurance procedures, medical physics staff, nursing and physician personnel as well as a whole host of other items, the most important of which is meticulous examination of selected patient charts. In the appendix, standards developed by the American College of Radiation Oncology, are reported.

Accreditation↗
PubMedDate not supplied

Interstitial hyperthermia.

The effectiveness of hyperthermia as a treatment modality for cancer continues to gain popularity in the medical community. One of the disappointing findings has been the inability to deliver uniform thermal doses to tumor volumes. This inability to heat certain tumors is due to a variety of physical and physiologic phenomena. To increase the ability of heating tumors, local interstitial techniques have been developed that are proving to be safe and effective. These techniques employ implanted microwave or radiofrequency antennae for the delivery of local thermal doses. Recently, investigations into the placement of interstitially located ferromagnetic seeds for local hyperthermia have also been conducted. The seeds can be heated by delivery of a high-wattage RF magnetic field to the implanted volume by an external source after implantation. The tissue surrounding the ferromagnetic implant is heated by conduction of heat away from the implanted seeds. While these techniques have been effective, further development of the instrumentation for interstitial therapies is continuing. These developments will include the application of specific control circuitry for delivery of accurate thermal doses.

Animals↗
PubMedDate not supplied

Intraoperative radiation therapy (IORT) in rectal cancer: methodology and indications.

In intraoperative radiation therapy (IORT) a high dose of radiation is delivered to the tumor or to the tumor bed, thus favouring local control with no significant increase in toxicity. At present it is used to deliver a boost dose of radiation for rectal cancer in protocols which include preoperative external beam radiation therapy (ERT). From various experiences carried out in a number of centers, the technical and methodological features of this procedure have been defined also relatively to cost-effectiveness in terms of a longer surgical treatment, involved specialized staff and resources. At the 5th IORT International Congress held in Lyon in September, 1994, of over 70 clinical studies reported, 15 were on rectal cancer with about 700 patients undergoing IORT. The growing interest in the use of this procedure in rectal cancer is explained by the natural history of the disease, burdened with a high rate of local recurrence, and by the possibility of preventing it with high doses of radiation. In primary tumors unresectable for cure and in local recurrence it is evidenced that ERT+surgery+IORT enable an improvement in local control and survival as compared to ERT alone. Results are better when surgery is radical. Several studies deal with the role of preoperative combined concomitant radiochemotherapy which can favour a radical surgery. A sizeable percentage of these patients will present with metastasis, thus adjuvant chemotherapy seems suitable. A role of IORT is envisaged also for resectable high risk tumors, however results should be confirmed by larger clinical series.

Combined Modality Therapy↗
PubMedDate not supplied

Brachytherapy for pancreatic cancer: a review.

Brachytherapy has been used for pancreatic cancer for over eight decades. Appositional, interstitial and intraluminal applications have been employed. Data from approximately three hundred cases are summarized in this review. The most common form of brachytherapy. Although this procedure, when combined with external beam radiation therapy and systemic chemotherapy, provides the best possible local control of pancreatic cancer, it is a hazardous procedure in most hands. Hopefully, the new techniques, such as intraluminal brachytherapy and infusional brachytherapy, will less prone to serious complications and they will prove to be efficacious in the management of cancer of the pancreas.

Brachytherapy↗