Indications, techniques and results of postoperative brachytherapy in cancer of the oral cavity.

PURPOSE/OBJECTIVE: We tried to reduce the number of local recurrences after surgery and external beam irradiation (EBI) in carcinoma of the oral cavity, when margins were positive or close. MATERIAL AND METHODS: From 1980 to 1992, we treated 97 cases of carcinomas of the oral cavity by postoperative brachytherapy. Surgery was combined with EBI+brachytherapy in 51 cases and with brachytherapy alone in 46 cases. We treated 29 T1, 34 T2, 30 T3T4 and four Tx (73% were N0 at first examination and 23% had positive nodes). The type of surgery is analysed. Brachytherapy was performed in one or two planes along the surgical scar. If the mandibular rim was resected, especially when the tongue or the remaining floor were sutured to the internal face of the inferior lip or to the buccal mucosa, the bridge technique was used. To decrease the dose to the inferior part of the mandible, the bridge was modified thanks to experimental dosimetry. RESULTS: At 5 years, the local control (LC) is 89%, the locoregional control (LRC) 82%, the specific survival (SS) 74% and the overall survival (OS) 67%. COMPLICATIONS: We noted 19% of grade 1 (minor), 12% of grade 2 (moderate) and 6% of grade 3 (major) complications. CONCLUSION: Compared with the results of the literature, we think that postoperative brachytherapy can improve classical radiosurgical results in selected cases with a risk of local recurrence.

Effects of selenium on UVA-induced lipid peroxidation in cultured human skin fibroblasts.

The effect of selenium on the lethal action of ultraviolet radiations and on the lipid peroxidation induced by exposures to ultraviolet A (320-400 nm; 360 kJ.m-2) and ultraviolet B (290-320 nm; 2 kJ.m-2) have been measured in cultured human skin fibroblasts. The experiments have been performed with either pure selenium or a spring water containing selenium and other trace elements (zinc and strontium). For cells cultured in a standard medium containing 10% fetal calf serum, no effect of selenium or spring water addition to the culture medium was observed on the lethality or on the peroxidative process induced by ultraviolet A and B radiations. Concurrently, there was no detectable increase of the seleno-dependent glutathione peroxidase activity. For cells previously depleted in selenium by a culture in a medium containing only 2% serum, a protective effect of selenium can be detected. Depending on the fibroblast donor, we observed (1) a protective effect on lethality of dividing fibroblasts induced by ultraviolet A radiations, (2) a protective effect on lipid peroxidation induced by ultraviolet A radiations on dividing or quiescent fibroblasts and (3) an increase in glutathione peroxidase activity in fibroblasts.

Stereotactic radiosurgery: the Lyon experience.

From 10/1989 to 12/1992, 135 patients were treated, in Lyon, by Stereotactic Radiosurgery (RS) +/- External beam Radiotherapy (EBRT). Indications were AVMs or tumours that could not be cured by embolisation or/and surgery and are not larger than 30 to 35 mm. Lesions received 15 to 20 Gy (70% isodose) in one course. Among the 42 AVMs, only one rebled 6 months after RS and 9/15 had clinical improvement. Thirty-one had a radiological follow-up of 4 to 29 months after RS. Ten were totally obliterated, seven regressed more than 80% and six had a reduction of 50 to 80% of their AVM. Three grade 3 radio necrosis occurred for a cerebral trunk AVM and two large lesions. Three of the 15 treated meningiomas progressed after RS, 2 of them were controlled by conventional surgery. Four out of nine presenting symptoms had clinical improvement and, with a radiological follow-up of 4 to 24 months, 5 were stabilised and 6 regressed. Two grade three complications occurred for large lesions. The biological and radiological results of RS were good for the 42 treated pituitary adenomas but the high visual complication rate (12/42 with 8 grade 3) was too important and we stopped RS for these tumours except for small (less than 2 cm) adenoma at some distance from the optic chiasma. The visual complications were related to the tumour volume, the distance between the adenoma and the visual tract and pre-existent visual alterations.(ABSTRACT TRUNCATED AT 250 WORDS)

Membrane damage induced in cultured human skin fibroblasts by UVA irradiation.

Irradiation of cultured human skin fibroblasts with ultraviolet light from 320 to 400 nm (UVA) leads to a decrease in the membrane fluidity exemplified by an enhanced fluorescence anisotropy of the lipophilic fluorescent probe 1-[4-trimethylamino)-phenyl]-6-phenylhexa-1,3,5-triene. This UVA-induced decrease in fluidity is associated with lactate dehydrogenase leakage in the supernatant. Vitamin E, an inhibitor of lipid peroxidation, exerts a protective effect on both phenomena. Therefore, this UVA-induced damage in membrane properties may be related to lipid peroxidation processes. Moreover, exponentially growing cells are more sensitive to these UVA-induced alterations than confluent cells.

Ultraviolet A-induced lipid peroxidation and antioxidant defense systems in cultured human skin fibroblasts.

Cultured human skin fibroblasts from healthy donors were irradiated with 180 kJ.m-2 ultraviolet (UV) A (320-400 nm) and assayed for thiobarbituric acid-reactive substances (TBARS), taken as an indicator of lipid peroxidation. Antioxidant defenses, including total glutathione (GSH) levels, superoxide dismutase (SOD), glutathione peroxidase (GSHPx), and catalase (Cat) activities were simultaneously assayed before and after irradiation. For the various donors, with different activities of these antioxidant systems before irradiation, TBARS correlated positively with SOD activity and negatively with Cat activity, whereas no correlation with GSH level or GSHPx activity was found. These data support the view that O2- is generated by UVA irradiation. They also suggest that H2O2, arising from O2- dismutation by SOD is not completely removed by Cat. Thus, the sensitivity of human fibroblasts to UVA-induced lipid peroxidation depends on a balance between SOD and Cat activities. After UVA irradiation, Cat activity was strongly inhibited, whereas GSH level was slightly decreased. By contrast, GSHPx and SOD activity remained unchanged after UVA irradiation.

An original technique of brachytherapy for T1 T2 carcinomas of the mobile tongue.

Twenty-four patients with T1 or T2 (17 T1 N0, 7 T2 N0 not exceeding 3 cm) epidermoid carcinomas from the middle third of the mobile tongue benefit from brachytherapy with "cavaliers-legos" consisting of guide-gutters that are inserted in a rigid support (legos) and covered with a lead plate. Several advantages can be advocated with this technique: easy implantation even with local anaesthetic, no risk of bleeding, good parallelism between Iridium wires, protection of the mandible with the lead plate. Local control was achieved in 22/24 patients (92%). Four patients (16%) developed soft tissue necrosis but only one required surgical intervention and no mandibular necrosis was seen.

[Stereotactic radiosurgery. Preliminary experience of a team of Lyon]. / La radiothérapie stéréotaxique multifaisceaux. Expérience préliminaire d'une équipe lyonnaise.

Radiosurgery (RS) is a new technique that is being developed worldwide to treat a variety of central nervous system (CNS) diseases. We report preliminary results concerning the first 35 patients treated at our institution between October 1989 and December 1990. These patients presented with pituitary adenomas (PA: 12 patients), primary CNS tumors with different histologies (11 patients), arteriovenous malformations (AVM: 6 patients), acoustic neurinomas (3 patients) and CNS metastases (3 patients). All patients were treated with a linear accelerator and received a single dose of 20 Gy delivered on the 70% isodose curve localized stereotactically by mean of either a CT scan or angiography. Preliminary results with a median follow-up of 26 months were as follows. AVM had totally disappeared in 3 patients after 12 and 17 months, and remained stable in 3 at 6 and 26 months. In 3 PA patients, the adenoma was partially regressed on the CT scan and, in 2 patients, the visual field was moderately improved; none experienced clinical improvement due to hormonal hypersecretion. One patient with neurinoma experienced clinical improvement, but the CT scan remained unchanged in the 3 patients. Of the patients with primary or secondary tumors, 8 exhibited a reduced lesion diameter on the CT scan, but 3 died later of progressive disease. Complications were not rare. In 7 patients, delayed reactions were observed: one case of cerebral edema reversed under corticotherapy; and 6 cases of neurological impairment due to brain necrosis, reversed in only one. RS appears to be an interesting approach for the treatment of deeply located AVM and for small acoustic neurinomas.(ABSTRACT TRUNCATED AT 250 WORDS)

[Evaluation of the consequences of signing a written consent on physician-patient relations. Apropos of Huriet's legislation]. / Evaluation des conséquences de la signature d'un consentement écrit sur la relation médecin-malade. A propos de la loi Huriet.

Whenever an innovative treatment or a research protocol is proposed to a patient, the "loi Huriet" requires a written consent from the patient. This is an important change in the field of the interrelation between the doctor and his patient. To evaluate the impact of this written consent we asked 215 patients who have signed a consent form to answer a questionnaire at the end of their radiation treatment. The signature appears as an important event. The majority of the patients (70%) is not shocked by this procedure. In 97% of cases, in spite of this written relation, the patients keep intact their confidence in their doctor. Sometimes this consent form may improve the information given to the patient and it should not be seen as an obstacle for the development of research trials. There are still many problems to be solved as regards the information of the patient and the application of the "loi Huriet".