Biomedical subjects
Publications and source records attributed to V Michelet.
[reaction: see text] The easily prepared catalyst systems PdCl(2), RhCl(2)(COD)(2), NiCl(2).6H(2)O, or Ni(COD)(2)/TPPTS have been found to form a C-C bond in organoaqueous medium. Intramolecular metallo-ene reactions have been efficiently realized. Metal selectivity has been discovered.
The prevalence of serum anti-phospholipid antibodies (aPL) was evaluated in multiple sclerosis (MS) patients to search for a possible association with a distinct form of the disease. Anti-cardiolipin antibodies (Ab) (aCL) and anti-beta 2 glycoprotein I Ab (abeta2GPI) were measured together with antinuclear Ab (ANA), anti-double-stranded DNA Ab (anti-ds DNA) and anti-myelin Ab in 89 patients. Twenty-nine (32.6%) patients had serum aPL, 19xaCL (15 of the IgG and four of the IgM isotype), 14 abeta2GPI (two IgG and 12 IgM) (four of these patients had both Ab). Prevalence of aCL correlated with that of ANA, which were positive in 52 patients (P=0. 005) and with anti-myelin Ab detected in two patients (P=0.046) but not with that of anti-ds DNA (mostly of the IgM class) detected in 28% of case by ELISA. No correlation could be found between aPL and age, sex, duration of the disease from diagnosis, category of MS, clinical course, clinical symptoms, serum IgM levels nor atypical lesions by magnetic resonance imaging. Hence, aCL and abeta2GPI are neither rare in MS nor associated with a specific clinical form of the disease and they cannot be a diagnosis exclusion criteria.
Tumors of the salivary glands are exceptional, representing approximately 2% of head and neck tumors. The parotid gland is most often involved, at a frequency reaching 80%. Histology examination generally shows a pleomorphous adenoma. The choice of a surgical technique best adapted to curative treatment depends on the type of tumor and is widely debated. Our management strategy is based on simultaneous histology examination and superficial parotidectomy. Several pre and intra-operative factors determine the need for resection. We verified our strategy with a retrospective study.
Fibrous dysplasia accounts for approximately 2% of bone tumors. The ribs, proximal femurs and cranio-facial bones represent the majority of bone lesions. Surgery is the mainstay of treatment but the technique is controversial: conservative surgery or removal of dysplastic lesions followed by implantation of autogenous bone graft. The aim of this study was to assess the indications of each method. The medical records of 25 patients with fibrous dysplasia of the cranio-facial bones treated between January 1, 1980 and December 31, 1994 at the Department of Maxillofacial Surgery, Centre Hospitalier Universitaire de Bordeaux, France, were reviewed. Fourteen (56%) patients were women and 11 (44%) men. The median age at the time of diagnosis was 23 years (ranging from 8 to 56 years). The mean follow-up was 8 years. Two patients were unavailable for follow-up after treatment. The primary sites of the tumors were the mandible (n = 19 [76%]), maxilla (n = 1 [4%]) and skull (n = 5 [20%]). For mandibular lesions, the primary treatment always included a correction of deformations and asymmetry, which was the only treatment in 14 cases. Two patients required subsequent surgery to reduce further bone enlargement (1 and 2 years later in the first case and 11 years later in the second) without further problems. In 3 cases a segmental mandibulectomy followed by implantation of autogenous bone graft was required, and no further recurrence was observed. Therefore, the success rate of conservative surgery was 74% initially, and up to 86% after subsequent surgery. Skull lesions, although often very extensive, were remarkably stable and asymptomatic. They were successfully treated 4 times by conservative surgery, mainly for cosmetic reasons. One patient, with an ethmoidal tumor producing a mass effect along the course of the optic nerve, underwent a combined cranio-facial resection. As for the only maxillary tumor, three curettages were performed throughout an 11-year period and there was no evidence of further recurrence 4 years after the last intervention. In all cases, conservative surgery may be recommended as primary treatment of fibrous of the craniofacial bones, providing essential structures like the optic nerve are not at risk. Cosmetic results and local control proved excellent, and a further removal of the tumor remained feasible in the event of a recurrence. Success or failure did not correlate with tumor size, which justifies the use of this technique.
Radical neck dissection was the golden standard of treatment for cervical nodes in head and neck tumors. From the seventies, the preservation of the spinal accessory nerve has become increasingly popular in order to improve the functional result of the neck dissections. The aim of this study was to assess the degree of functional disability associated with each type of neck dissection and the value of anatomical references for dissection of the spinal accessory nerve. One hundred twenty seven patients were evaluated 1 month and 1 year after radical, functional or supraomohyoid neck dissection with a questionnaire and a physical examination. Anatomical measurements of the spinal accessory nerve were performed in 20 patients. We found considerable or severe shoulder dysfunction in 7%, 34% and 51% respectively of patients in whom supraomohyoid, functional and radical neck dissections were performed. Furthermore 49% of patients having undergone a radical neck dissection had little or no symptoms. Sacrifice of the spinal accessory nerve in radical neck dissection may lead to shoulder dysfunction. A functional disability may also be associated, although in a less extent, with any neck dissection in which the spinal accessory nerve is dissected and placed in traction. There is a large variation in the degree of functional disability and pain in patients with similar neck dissections. The course of the spinal accessory nerve in the neck makes it particularly vulnerable to injury during the dissection near the sternocleidomastoid muscle and in the posterior cervical triangle.
Marginal mandibulectomies are now widely performed in the anterior aspect of the mandible providing that the preoperative clinical and radiologic evaluation shows no bone invasion. These marginal resections can be extended to the posterior area. Molar, retromolar and ascending ramus resections can be performed. This removes the upper bone segment preserving the dental canal whenever possible. From 1990, 14 patients were treated with this technique for carcinoma of the retromolar triangle (9 cases) and oropharynx (5 cases). 11 different flaps were used to cover the soft tissue defect and 3 direct sutures were performed. Eleven patients underwent postoperative radiotherapy with a mean dose of 58 Gray. Median follow-up was 32 months. Functional and cosmetic results were very satisfactory due to preservation of mandibular continuity. We found no osteomyelitis, postoperative fracture or radionecrosis. This technique avoids a segmental resection in some well-defined cases and the disability produced as a result of this treatment. There is therefore, no need for complex reconstruction and the operating time is shortened in fragile patients.
Carcinoma of the oral cavity in patients less than thirty years of age is quite uncommon. Moreover, the usual tobacco and alcohol exposure is not found in these patients. We reviewed retrospectively the medical files of 7 patients with squamous cell carcinoma of the oral cavity treated between 1980 and 1993. Six patients were male. Mean age was 26 years. The primary site was staged T1 in 2 patients, T2 in 3 patients, T3 in 1 patient and T4 in 1 patient. The results of treatment suggest that there is no difference in control rate between this group and older patients. It is difficult to draw conclusions from most of published reports because studies often include patients up to fourty years of age and tumors of various anatomic sites. Young age and alcohol and tobacco exposure do not appear significant factors of prognosis.
The aim of this study was to assess the reconstruction of floor of the mouth defects after cancer surgery. The medical records of 140 patients treated between January 1st, 1987 and December 31st, 1995 were reviewed. Ninety-six patients had primary reconstruction: there were 82 cutaneous or osteomyocutaneous flaps and 14 microsurgical transfers. Among these patients 15 had titanium mandibular reconstruction plates. The reconstruction procedures and postoperative follow-up were evaluated. Healing by first intention is appropriate for superficial soft tissue defects. The nasolabial flap is used only for small mucosal defects. A forearm flap should be the first choice treatment for large soft tissue defects owing to its plasticity and reliable vessels. Segmental mandibular resections often imply mandibular reconstruction. Titanium plates may be used alone or with a cutaneous flap. Tolerance of plates after radiotherapy is very good and they are an effective method of reconstruction for fragile patients.
OBJECTIVE: To evaluate treatment of ameloblastoma of the jaws and suggest a more aggressive approach for well-defined cases. SETTING: Referral center. PATIENTS: Forty-one patients were treated for ameloblastoma of the jaws. RESULTS: Seventeen patients had a local recurrence; 14 had initial curettage and three had initial resection. Seven patients had two or more recurrences. Eight patients underwent radiotherapy; two died of progressive disease. CONCLUSIONS: Ameloblastoma had a high rate of local recurrence if not adequately removed. Segmental resection for the mandible and partial maxillectomy for the maxilla should be the primary treatment; marginal resection is appropriate only for small primary tumors. For multiple recurrences, radiotherapy is effective, and surgery and radiotherapy (50 Gy postoperatively) should be used in selected cases.
The medical records of 31 patients with histologically proven primary carcinoma of the parotid gland seen between January 1980 and December 1992 were reviewed. The efficiency of combined treatment both on locoregional control and overall survival was assessed. Twenty nine patients underwent extensive surgery and postoperative radiotherapy, two patients underwent extensive surgery alone. Locoregional control of disease at the end of treatment was achieved in 29 patients (94%). Eleven patients had recurrences. For the complete series the overall two and five-year survival rates were 73% and 46% respectively. Even in case of locoregional control with combined treatment, overall survival rates are low because of distant metastases.
Described since 1976, the lateral trapezius flap is not very used in cervico facial reconstructive surgery because of its dissection which is considered as difficult and because of the variability of its vascular pedicle. This latter problem can be removed by the systematic use of preoperative arteriography. We present our retrospective experience of 89 flaps (70 cases of tumors and 19 cases of balistic pathology. We can conclude that the lateral trapezius flap owns specific indications: cutaneous and mucous defects of lips and cheeks, defects of pharyngeal area, defects of floor of the mouth considering of its thin thickness, mandibular defects where it takes place between reconstructive plates and revascularized bone transplants especially for the symphysis area.
The aim of the study was to assess the results of segmental mandibular resections and the validity of mandibular reconstructions. The medical records of 95 patients treated between January 1, 1987 and December 31, 1992 were reviewed. There were 82 (86%) carcinomas, 9 ameloblastomas and 4 sarcomas. Among the 82 patients treated for carcinoma, the overall 2- and 5-year survival rates were 70% and 33% respectively. The functional results evaluated one year after surgery showed no significant difference according to the reconstruction procedure: myocutaneous flap, osteomyocutaneous flap, titanium mandibular reconstruction plate or microsurgical transfer. The most important factor in functional rehabilitation is the amount of soft tissue resected. In head and neck oncology, aggressive surgical reconstruction of the mandible must only be used in patients with good general status and fair survival probability.
Soft tissue sarcomas of the head and neck account for less than 1% of all malignant neoplasms in this region. A significantly increased risk of treatment failure is associated with high histologic grade, leading to an aggressive treatment. The medical records of 17 patients with soft tissue sarcomas of the head and neck were reviewed. They were divided into two groups according to age: 13 adults and 4 children. The former underwent wide surgical excision with postoperative radiotherapy in some cases and possibly chemotherapy. The 2 and 5 years survivals were 54% and 46% respectively. The latter, with rhabdomyosarcoma, underwent multimodality treatment (chemotherapy, surgery, radiotherapy). The 2 years survival was 50%. The mainstay of treatment of soft tissue sarcomas of the head and neck in adults remains surgery. Patients with incomplete resection or high grade tumour should receive more aggressive treatment (surgery and postoperative radiotherapy). The use of systemic chemotherapy has showed no statistically significant improvement in local control or survival. However, for rhabdomyosarcoma in children, chemotherapy is an essential part of treatment.
The aim of this study was to assess the use of titanium mandibular reconstruction plates after cancer surgery. The medical records of 36 patients were reviewed. The mean follow-up was 22 months. All patients had primary reconstruction of the mandible with Leibinger titanium plates. Thirty patients underwent postoperative radiotherapy with the plate in the field. The mean dose was 60 Grays over 6 weeks and the overdosage into tissues was reduced to 5%. Thirty patients (83%) had retained the plate at 6 months and no sign of osteomyelitis was found in any patient. Quality of speech and deglutition were satisfactory in 63% and 94% of the patients respectively; sixty-six p. cent of them found their cosmetic appearance good or excellent. The overall success rate of the technique was 74%. This technique did not excessively prolong operating time unlike microvascular transfer. Plates are an effective method of primary reconstruction in patients with advanced cancer and uncertain long-term survival. Tolerance of plates after radiotherapy is outstanding. Speech, deglutition and facial contour are immediately restored and further bone reconstruction is feasible.
Head and neck bone sarcomas are very uncommon tumors. Therefore, treatment modalities are not clearly established. The medical record of 12 patients with bone sarcoma of the jaw were reviewed. Six patients with osteosarcoma underwent primary chemotherapy followed by wide surgical resection, radiation therapy or combined radiosurgical treatment. The 2 and 5 years survivals were 66% and 40% respectively. Five patients with chondrosarcoma were treated by wide surgical resection alone or combined with postoperative radiotherapy and possibly chemotherapy. All patients were alive; the mean follow-up was 9 years. One patient had Ewing's tumor. Osteosarcoma and chondrosarcoma in head and neck patients have a high rate of local recurrences. Surgery is the mainstay of treatment. Patients with voluminous tumors and high-grade lesions should receive postoperative radiotherapy. The role of chemotherapy has not been defined.
The study of adenoid cystic carcinoma of the salivary glands is limited by the paucity of series described and the lack of prospective reports. The medical records of 21 patients with histologically proven adenoid cystic carcinoma seen between January 1975 and December 1991 were reviewed. The efficiency of postoperative radiotherapy both on locoregional control and overall survival was assessed. Seventeen patients underwent extensive surgery and postoperative radiotherapy. Three patients had recurrences in the surgery and postoperative radiotherapy group. Two patients who underwent surgery alone presented tumor recurrences. For the complex series the overall five and ten-year survival rates were 83% and 67% respectively. For the 17 patients in the surgery and postoperative radiotherapy group, five and ten-year survival rates were 87% and 77% respectively. These results show postoperative radiotherapy to be effective in decreasing the recurrence rate which is largely reported elsewhere.