ABSTRACT
Nomograms for square planar arrays spanning the range from 3 X 3 cm to 10 X 10 cm were developed. The nomograms are intended to be used for pretreatment planning of implant geometry, so that the therapist may enter the operating room with a plan for the optimal implant in mind. We show that clinically useful implants are those in which the reference isodoses are fully coupled. Decoupling occurs when ribbon spacing exceeds approximately 1.2 cm and leads to undesirable "cold spots" within the treatment volume. Ribbon spacing of 1.0 cm is recommended. This represents a trade-off between adequate ribbon coupling and minimum tissue damage from trocar placement. For clinically useful arrays, the area enclosed by the reference isodose contour (85% of the maximum dose rate) is approximately 50% of the array area. Reference isodose contour and its enclosed area are independent of seed strength for a given array, as long as all seeds within the array are of equal strength.
Subject(s)
Brachytherapy/methods , Breast Neoplasms/radiotherapy , Iridium/therapeutic use , Radioisotopes/therapeutic use , Skin Neoplasms/radiotherapy , Humans , Radiotherapy DosageABSTRACT
The variability of malignant melanoma in its response to irradiation is well documented. Recent radiobiological studies suggest that high individual dose and low total fraction regimens will enhance the responsiveness of this tumor to irradiation. The experience of the Ellis Fischel State Cancer Hospital and the Cancer Research Center, Columbia, Missouri was reviewed with particular attention to such radiotherapeutic regimens. Of 41 lesions in 27 patients, the overall response rate to irradiation was 37%. When regimens using more than 400 cGy per fraction were analyzed, a 67% response rate was noted. Complete response and small volume of tumor correlated significantly (p = 0.008) with long-term survival.
Subject(s)
Melanoma/radiotherapy , Female , Humans , Male , Neoplasm Metastasis , Orbital Neoplasms/radiotherapy , Prognosis , Radiotherapy Dosage , Urethral Neoplasms/radiotherapy , Vaginal Neoplasms/radiotherapyABSTRACT
Pseudo-obstruction of the colon, or Ogilvie's syndrome, is characterized by an adynamic, dilated, unobstructed colon, the exact cause of which remains obscure. Although several precipitating factors have been described in the literature, we have observed three patients whose pseudo-obstruction of the colon occurred during interstitial and intracavitary pelvic irradiation. Such a cause has not been noted previously. Pseudo-obstruction of the colon can have serious consequences if it is not recognized early and treated vigorously.
Subject(s)
Colonic Diseases/etiology , Intestinal Obstruction/etiology , Intestinal Pseudo-Obstruction/etiology , Radiotherapy/adverse effects , Aged , Cecal Diseases/diagnostic imaging , Cecal Diseases/etiology , Colonic Diseases/diagnostic imaging , Female , Humans , Intestinal Pseudo-Obstruction/diagnostic imaging , Male , Middle Aged , Pelvic Neoplasms/radiotherapy , Radiography , SyndromeABSTRACT
The management of inflammatory carcinoma of the breast remains a therapeutic dilemma because of two basic conceptual problems: local control and systemic micrometastatic disease. Appropriate management requires a multidisciplinary approach involving radiation therapy, surgery, and medical oncology.
