Vincent Sampiere

Hypothalamic, pituitary and thyroid dysfunction after radiotherapy to the head and neck

One hundred-ten patients who had nasopharyngeal cancer and paranasal sinus tumors and were free of the primary disease were studied one to 26 years following radiotherapy. There were 70 males and 40 females ranging in age from 4 to 75 years, with a mean age of 36.5 years. During therapy both the hypothalamus and the anterior pituitary gland were in the field of irradiation. The radiation dose to the hypothalamus and the anterior pituitary gland was estimated to be 400 to 7500 rad with a median dose of 5618 rad to the anterior pituitary gland and a median dose of 5000 rad to the hypothalamus. We found evidence of endocrine deficiencies in 91 of the 110 patients studied. Seventy-six patients showed evidence of one or more hypothalamic lesions and 43 patients showed evidence of primary pituitary deficiency. Forty of the 66 patients who received radiotherapy to the neck for treatment or prevention of lymph node metastasis showed evidence of primary hypothyroidism. The range of the dose to the thyroid area was 3000 to 8800 rad with a median of 5000 rad. One young adult woman who developed galactorrhea and amenorrhea 2 years following radiotherapy showed a high serum prolactin level, but had normal anterior pituitary function and sella turcica. She regained her menses and had a normal pregnancy and delivery following bromocriptine therapy. These results indicate that endocrine deficiencies after radiotherapy for tumors of the head and neck are common and should be detected early and treated. Long-term follow-up of these patients is indicated since complications may appear after the completion of radiotherapy.

Minicolpostats, dome cylinders, other additions and improvements of the fletcher-suit afterloadable system: Indications and limitations of their use☆

Abstract The Fletcher prelosidable colpostat and intrauterine system was described in 1952. In the early 1960s it was made afterloadable by Suit et al; in 1968 we added cylindrical colpostats with specific indications for their use. Since the description of the first afterloadable system, several modifications have been made without departing from the fundamental features of the original preloadable model. The importance of these features was discussed at length in a recent publication. In this paper we describe improvements in design and introduce the minicolpostats and the dome colpostats. In addition, we discuss indications and limitations of their use.

Can the fletcher gamma ray colpostat system be extrapolated to other systems

The basic rules governing the intracavitary application or radium for the treatment of carcinoma of the uterine cervix at M. D. Anderson Hospital and Tumor Institute were established in the early 1950s. The Fletcher preloadable colpostats were designed with specific purposes. The aim was to provide a colpostat that could be easily applied and maintained in the lateral fornices, and that could allow an increase in paracervical and parametrial irradiation by better distribution of the radium sources and the addition of bladder and rectal shielding. In the 1960s, the original ovoids, and tandems were adapted so that they could be afterloaded with the standard radium tubes, but the original design restrictions were maintained in the afterloadable models. Additionally, a number of afterloadable colpostats, some with similar external design have become available commercially, but x‐ray and measurements of these colpostats show that the manufacturer did not adhere to the original design restrictions. In addition, several of these colpostats have been modified for use with cesium. Extreme caution is advised in the use of colpostats built elsewhere without proper supervision, other colpostats, and sources other than radium. Tables and guidelines outlined in Fletchers publication are to be used only with the recommended applicators and sources. The use of normalized doses at point A does not reflex the doses to bladder and rectal areas, because these doses vary with the type of applicator employed and the nature and physical characteristics of the radioactive source.

WHOLE ABDOMINAL IRRADIATION BY COBALT-60 MOVING-STRIP TECHNIC.

The moving-strip technic was developed in Manchester, England, during the 1940s for utilization with orthovoltage irradiation. Since 1957 it has been applied in the M. D. Anderson Hospital and Tumor Institute to Co60 therapy. The purpose of developing such a technic was to find a method of irradiating the whole abdomen, which would improve systemic tolerance. There are two main types of disease which require total abdominal irradiation: The ovarian carcinomas, and the abdominal manifestations of the lymphomas. A variety of clinical situations such as seminomas, with extensive involvement of the periaortic nodes, also call for such a technic. Static Field Technic of Whole Abdominal Irradiation Irradiation to the whole abdomen should be given preferably in one undivided volume with homogeneous dosage. With either conventional 250-kv or supervoltage roentgen therapy, the whole abdomen can be irradiated through large parallel opposed portals, if the distance from the skin to the target is sufficiently great,...

Fast neutron radiotherapy for locally advanced pelvic cancer

Between March 1973 and May 1975, 82 patients with locally advanced pelvic tumors were treated with 50 MeVd→Be neutrons. Seventy‐nine have been included for analysis. The clinical material included 51 patients with gynecologic cancers, 15 with colorectal adenocarcinomas, and 13 with prostatic adenocarcinomas. Three treatment approaches have been used: 1) neutrons only—160 radνγ twice weekly, 2) neutron boost following 25 MV photon irradiation—160 radνγ twice weekly, and 3) mixed beam—photons (200 rads) three times weekly and neutrons (65 radνγ) twice weekly. The preliminary results with the mixed beam are superior to those obtained with neutrons only or a neutron boost. However, the patients treated with the mixed beam have presented with slightly less advanced cancer and have been treated to slightly higher equivalent doses than those treated with neutrons only. The superior results with the mixed beam may be related to a better volume distribution and/or five‐times weekly fractionation.

Afterloading Vaginal Irradiators

The authors describe a set of vaginal cylinders of variable diameter (2 to 5 cm) and of adaptable length. With these almost any vagina may be fitted at the time of surgery, and exposure to personnel is eliminated. Lead may be incorporated in the cylinders to partially shield either the vagina or the rectum.

Brachytherapy techniques in the treatment of carcinoma of the cervix

The basic rules governing the intracavitary application or radium for the treatment of carcinoma of the uterine cervix at M. D. Anderson Hospital and Tumor Institute were established in the early 1950s. The Fletcher preloadable colpostats were designed with specific purposes. The aim was to provide a colpostat that could be easily applied and maintained in the lateral fornices, and that could allow an increase in paracervical and parametrial irradiation by better distribution of the radium sources and the addition of bladder and rectal shielding. In the 1960s, the original ovoids, and tandems were adapted so that they could be afterloaded with the standard radium tubes, but the original design restrictions were maintained in the afterloadable models. Additionally, a number of afterloadable colpostats, some with similar external design have become available commercially, but x-ray measurements of these colpostats show that the manufacturer did not adhere to the original design restrictions, In addition, several of these colpostats have been modified for use with cesium. Extreme caution is advised in the use of colpostats built elsewhere without proper supervision, other colpostats , and sources other than radium. Tables and guidelines outlined in Fletchers publication are to be used only with the recommended applicators and sources. The use of normalized doses at point A does not reflect the doses to bladder and rectal areas, because these doses vary with the type of applicator employed and the nature and physical characteristics of the radioactive source.

A Practical Method for Correcting the Primary Component of the Field of a 60CO Irradiator at Off-Axis Points

Decrease in the primary dose with distance from the central axis was studied for two 60Co irradiators. Measurements were made with an ionization chamber, and isoresponse curves were obtained which were significantly different for the two machines. An investigation of such plots for different field sizes indicate that they cannot be scaled numerically and it is suggested that to make off-axis corrections, a library of measured isoresponse plots for different field sizes should be obtained which is extensive enough so that interpolation errors are small.