Biomedical subjects

D R Goffinet

Publications and source records attributed to D R Goffinet.

At least 91 records · Page 5Linked to original sources

PubMed1976

The metal/tissue interface effect in irradiation of the oral cavity.

Metal dental prostheses or overlays may lead to increased mucosal reactions of adjacent tissue surfaces during intensive irradiation of the oral cavity. The dosimetry of this phenomenon was investigated by irradiating dental phantoms with 4-and 6-MeV photons. Gold and amalgam interfaces may produce local mucosal doses as high as 150-170% depending on the beam geometry, but doses of 111-126% for gold crowns and about 109-118% for amalgam fillings were found for opposed-beam configurations. 2-4 mm of tissue-equivalent absorber is sufficient to re-establish a homogeneous dose distribution and should be employed throughout therapy whenever dental extraction is unwarranted. The radiobiological exaggeration of the interface effect in treatment with opposed beams using one field per day is discussed.

Absorptiometry, Photon↗

PubMed1976

The effects of single and multifraction radiation courses on the mouse spinal cord.

Thoraco-lumbar spinal cord segments of C3H mice were irradiated with 250 kVp x rays and the acute and late effects of several variables were compared: single and multifraction radiation courses; changes in the length of irradiated spinal cord; and multifraction studies in which three-week and three-month splits were compared to a continuous radiation course. A scoring system for assessing the degree of radiation-induced myelopathy was devised, using a scale ranging from 1.0 (loss of rear limb reflex extension) to 4.0 (paraplegia). A significant increase in severity of spinal cord radiation injury was noted when single doses were compared to equal doses given in 10 consecutive fractions. Increasing the irradiated segment from 6 to 12 mm was also associated with more severe and earlier radiation cord injury.

Animals↗

PubMed1976

Carcinoma of the oropharynx. Results of megavoltage radiation therapy in 305 patients.

Three hundred and five patients with oropharyngeal carcinomas received linear accelerator radiation therapy at the Stanford University Medical Center between 1956 and 1973. All were staged by the TNM system, using the UICC Classification of 1962. Actuarial five year survival for patients with tonsil cancers ranged from 50% to 18% for those with T1 and T3 lesions, respectively. Disease-free survival was higher than actuarial survival for patients with T1 and T2 lesions, reflecting an alteration of the latter curves by deaths from intercurrent diseases and second primary malignancies. Actuarial survival for patients with base of the tongue carcinomas was approximately 35% for those with T1 and T2 primary lesions and 22% for patients with T3 carcinomas. Considering all oropharyngeal sites of involvement together, clinically involved cervical lymph nodes were controlled by radiation therapy alone in 60 of 91 patients with N1 nodal involvement (67%), in twelve of 25 with N2 neck disease (48%) and in 46% of those patients with N3 involvement (34 of 74). Eighty-nine percent of patients whose lymph nodes were not controlled by radiation therapy alone also had uncontrolled primary cancers. Over 90% of the patients whole cervical lymph nodes were initially uninvolved remained free of late nodal metastases if at least the regional (first echelon) lymph nodes were included in the primary treatment fields. The results of a randomized trial which compared surgery and radiation therapy alone and the two modalities in combination for the treatment of a limited number of patients with advanced cancers of the oropharynx, supraglottic larynx and hypopharynx suggest that surgery alone is not the treatment of choice.

Carcinoma, Squamous Cell↗

PubMed1975

Carcinoma of the oral tongue and floor of mouth: fifteen years' experience with linear acceleration therapy.

One hundred fourteen patients with carcinoma of the oral tongue and floor of mouth were treated with high-dose megavoltage radiation at Stanford University from 1956 to1970. Actuarial 5-year survival for 56 patients with oral tongue lesions was: T', 73; T', 37%; and T', 19%. Similarly, for 58 patients with lesions of the floor mouth, 5-year survival was: T', 73%; T', 37%; and T', 25%. Local control of the primary was obtained in oral tongue T' lesions 10 of 11 times; T', 5 of 8; and T', 13 of 36 times. For floor of mouth, local control was: T', 22 of 26;T', 7 of 14; andT', 3 of 15. There was an indication that better control was obtained if interstitialtherapy was a planned part of the treatment. Dose for local control when external radiation alone was utilized was usually over 1900 rets. Patients with initially clinicallynegative nodes (TXNO) who had a low radiation dose to primary echelon lymph nodes developed later cervical lymph node metastases 38% of the time. In no case did late metastatic disease appear in patients whose necks were treated prophylactically.

Aged↗

PubMed1975

Treatment of chromophobe adenmas with megavoltage tirradiation.

From 1956-1972, 62 previously untreated patients with chromophobe adenomas received high-dose (average equivalent dose: 5700rads in 6 weeks) megavoltage (4-4.8 MeV) irradiation at Stanford, 33 postoperatively and 29 as the only intended treatment. Initialtreatment failure rates were 18% and 41%, respectively; however, overall control was 85% and 90%, despite 2 uncontrolled "invasive" adenomas in each group. Nine of the 12 failures in the group treated by irradiation alone had cystic tumors, and 9 of the 12 "failed" in less than 3 months. Despite a considerably greater degree of abnormal vision initially in the postoperative irradiation group, improvement of vision with treatment in that group was 83% (19% returned to normal) compared to 46% (only 8% to normal) in the irradiation alone group. Based upon an evaluation of the extent of findings at diagnosis and our results, we recommend surgical decompression followed by 5000 rads in 5 weeks for patients with any one or more of the following findings: 1)more than minimal depression of peripheral visual fields; 2) corrected visual actuity of less than 20/30 in either eye; or 3)more than 1-cm suprasellar extension of tumor. We recommend irradiation alone, as specified, for smaller adenomas accompanied by less extensive or no visual abnormalities.

Adenoma, Chromophobe↗

PubMed1975

Megavoltage irradiation in the treatment of gliomas of the brain and spinal cord.

Curative radiotherapy was attempted in treating 256 patients with unresected or partially excised gliomas of the brain and spinal cord. Survival decreased with increasing age, reflecting the different incidences of tumor types in various age groups. Actuarial 5-year survival ranged from 85% for cerebellar astrocytomas, to 47% for medulloblastomas, to 41% for cerebral hemispheric astrocytomas, and 0% for glioblastoma multiforme. Further improvements in survival utilizing radiotherapy are unlikely until new adjuncts are developed, for higher radiation doses may lead to a disproportionate increase in radiation complications.

Age Factors↗

PubMed1975

Bladder cancer: results of radiation therapy in 384 patients.

Between 1957 and 1972, 384 patients with bladder cancers were treated initially with megavoltage radiation therapy. Actuarial five-year survival ranged from 35 to 42% for Stages A and B1 tumors, and was 35, 22 and 7%, respectively, for Stages B2, C and D carcinomas. Approximately 30-40% of deeply invasive tumors confined to the bladder can be controlled with radiation therapy alone, directed solely to the bladder itself.

Aged↗

PubMed1975

Combined radiosensitizer infusion and irradiation of osteogenic sarcomas.

Three children with osteogenic sarcomas which were either unresectable or whose parents refused permission to amputate were treated with combined intra-arterial 5'bromodeoxyuridine (BUdR) infusion and high-dose-per-fraction megavoltage irradiation to the primary site. Pulsed, 48-hour BUdR infusions were performed prior to each 600-rad radiation therapy fraction, with a total radiation dose to the primary site of 4,200-4,800 rads in five weeks. Local control was obtained in all 3 children. One child is alive two years after treatment, another died with metastatic disease and the third patient who received radiotherapy to the lungs for pulmonary metastases is without evidence of disease one year later.

Bromodeoxyuridine↗

PubMed1975

Irradiation of clinically uninvolved cervical lymph nodes.

Of 402 patients with cancers of the oral cavity, oropharynx, and supraglottic larynx treated at Stanford between 1957 and 1972, 164 had clinically uninvolved cervical lymph nodes prior to the initiation of radiation therapy. Lymph node metastases developed later in 38 per cent of patients with primary oral cavity carcinomas who were treated with interstitial radium implants alone. No late cervical lymph node involvement was found in those patients who received high dose external irradiation to at least the primary site and first echelon lymph nodes. Lymph node failures were ultimately noted in 20 of the 140 patients (14 per cent), who received partial or complete neck irradiation, but 18 of these occurred in patients with uncontrolled primary lesions, suggesting that re-seeding of cervical lymph nodes had taken place rather than failure of the initial irradiation to control subclinical metastases. Our present policy is to treat the primary lesion and adjacent lymph nodes with high dose megavoltage techniques, combined with interstitial irradiation if possible. Bilateral supplemental inferior neck radiation ports are added for patients with advanced primary neoplasms and for those with clinically involved cervical lymph nodes. All other patients undergoing radiation therapy for stage T1 primary lesions and clinically negative necks also receive ipsilateral low neck irradiation. In addition, cervical lymph nodes are electively irradiated when the primary lesion has been resected. When these policies are adopted, the incidence of cervical lymph node failures is extremely low in patients whose primary sites remain controlled, and morbidity from the cervical radiation fields is negligible.

Humans↗

PubMed1974