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J P Homasson

Publications and source records attributed to J P Homasson.

At least 19 recordsLinked to original sources
PubMed2004

[Primary lung cancer in elderly subjects in France].

INTRODUCTION: There are few data on primary bronchial carcinoma in France. We report here the results of the study KBP 2000-CPHG in which there were 1868 patients aged 70 or more and 338 aged 80 or more. METHODS: We compared the patients under 70 (Group I) with those aged 70 or more (Group II) as well as with the details of the over 80's. RESULTS: Group II included significantly more women (17.4% vs 15.2%; p = 0.04), non-smokers (11.2% vs 5.3%; p<0.0001), patients of poor performance status (24.2% vs 14.5%; p<0.0001) and squamous carcinomas (44.5% vs 37.8%; p<0.001) than Group I, but fewer adenocarcinomas (27.2% vs 31.5%; p = 0.009) and as many small cell carcinomas (15.9% vs 16.9%; p = 0.32). In Group II there were less stage III and IV tumours (75.1% vs 78.1%; p = 0.0005) more symptomatic treatment (23.2% vs 6.1%) and radiotherapy alone (12.8% vs 3.8%; p < 0.0001). The results were similar beyond 80 years. On multivariate analysis age, performance status and stage appeared to be independent variables in the choice of curative or symptomatic treatment. CONCLUSIONS: Age alone is not therefore a limiting factor in the choice of treatment.

Age Factors↗
PubMed2001

[Lung autofluorescence. Preliminary study of two systems without laser illumination or photosensitization].

When illuminated with a certain wavelength, lung tissue emits a weak fluorescence. The fluorescence from normal tissue is different from that from diseased tissue. This technique can thus be used for early diagnosis of precancerous lesions. Technical manipulations are required to amplify the fluorescence signal. Numerous studies have used the LIFE (Lung Imaging Fluorescent Endoscope) to study lung diseases. This system of detection uses a laser helium-cadmium excitation source; the principal photosensitizing agents are hematoporphyrin derivatives. The cost, bulkiness and secondary effects have limited diffusion of this type of photodynamic diagnostic system. We have used 2 systems (SAFE 1000 Pentax and D-LIGHT Storz) successively in a prospective study to analyze autofluorescence of lung tissue without laser illumination or photosensitization. Fifty-four patients were selected for their risk factors. We were able to detect one case of severe dysplasia but did not identify any case of carcinoma in situ. Among 18 cases, 16 were evident with white light. Two were detected with autofluorescence used to orient biopsies while white light had only revealed a common inflammatory aspect. Thirty-nine low-grade lesions (metaplasia, dysplasia) were found. The systems are easy to use. Lower cost would allow more widespread use of these systems currently reserved for risk populations. These techniques broaden the scope of interventional endoscopy.

Adult↗
PubMed2000

An uncommon etiology of isolated pleural effusion. The ovarian hyperstimulation syndrome.

We report three cases of pleural effusion in the context of ovarian stimulation for in vitro fertilization. The ovarian hyperstimulation syndrome usually causes pleural effusion and ascites. When the latter is lacking, an isolated pleural effusion in a pregnant patient can be mistaken for pulmonary embolism. Early recognition of the condition should allow for an appropriate diagnostic and therapeutic management. Except for some rare but life-threatening complications, such as major hypovolemia or respiratory distress syndrome, the spontaneous outcome is usually favorable. The pathogenesis of this condition may involve an increase of capillary permeability due to the release of vasoactive mediators.

Adult↗
PubMed1999

Morphological changes induced by extensive endobronchial electrocautery.

Due to recent improvements of safety conditions for therapeutic devices, electrocautery is being considered with renewed interest in the field of therapeutic bronchoscopy. The efficiency of this technique for destructing intraluminal tumours is well documented and makes it an attractive alternative to Yttrium aluminium garnet (YAG) laser photo-coagulation. Little is known, however, about the morphologic changes induced by electrocautery within the bronchial wall structures. This information is, however, important since electrocautery has been proposed as an alternative to other techniques to treat superficial tumours of the bronchial wall. Soft coagulation, with autostop, using two different power setting (40 and 120 W), produced by a new generation of high frequency voltage regulated generators was applied circumferentially to the trachea or left main bronchus, in a series of 52 piglets. Early (48 h) and late effects (6 weeks) were assessed through gross examination (bronchoscopy and autopsy) and light microscopy. Early effects of electrocautery included coagulation necrosis of the mucosa only and intense acute inflammation extending deep into the bronchial structure. The inflammatory phase progressively resolved while extensive transmural fibrosis and deterioration of the cartilage plates developed. The nature and extent of these lesions did not depend upon the energy delivered (40 W versus 120 W). Retractile scar formation and loss of cartilaginous support then produced iatrogenic secondary stenoses. These results do not question the use of electrocautery to palliate endoluminal tumours but should make operators careful when treating extensive infiltration of the bronchial wall.

Animals↗
PubMed1999

[High-frequency thermocoagulation. Use in bronchial endoscopy].

High frequency thermocoagulation is a relatively recent technique of destroying tracheobronchial tumour mass. It selects the thermal effect of electrical current whilst avoiding the electrolytic and faradic effects of nerve and muscle stimulation. With gentle coagulation which is generally utilised the tissues are heated to between 70 and 100 degrees with the formation of water vapour and immediate destruction of the tissues. The electrodes are usually unipolar and are either rigid or flexible. The HF current which circulates across the tissues is gathered and evacuated by neutral electrodes. A new generation of fiberoptic bronchoscopes which isolate the exit current may optimise the safety of the procedure. New generators delivering a stable voltage controlled by a microprocessor enable the control of the process of coagulation and adapt the thermal energy delivered to the volume and nature of the tissue to be destroyed. The electrode is put in contact with the tissues. The immediate effects is similar to those described with laser. The simplicity, speed of utilization, minimal morbidity and relatively low cost has made this an interesting technique even in developed countries where the investment budgets are becoming more and more limited.

Bronchial Neoplasms↗
PubMed1998

Predictive factors for late toxicity after endobronchial brachytherapy: a multivariate analysis.

PURPOSE: To determine the predictive factors associated with hemoptysis and radiation bronchitis after endobronchial brachytherapy by univariate and multivariate analyses METHODS AND MATERIALS: One hundred forty-nine patients underwent endobronchial brachytherapy and were divided into three therapeutic groups: group 1: patients treated with palliative intent (n=47); group 2: patients treated with curative intent (small endobronchial tumors without mediastinal or general dissemination: n=73); group 3: patients also receiving external irradiation (n=29). One hundred twelve patients had previously received external irradiation. Brachytherapy was delivered with a dose per fraction ranging from 4 to 7 Gy and a prescription point between 0.5 and 1.5 cm, usually 1 cm from the source center. Two to six fractions were delivered according to the therapeutic group and clinical situation. The influence of the following variables on the incidence of hemoptysis or radiation bronchitis was studied: age, sex, Karnofsky score, therapeutic group, histologic type, endoscopic tumor length, dose per fraction, total brachytherapy dose, total external beam irradiation dose, total dose (brachytherapy dose plus external irradiation dose), volumes of the 100% and 200% isodoses, and volumes of the 7 and 14 Gy isodoses. RESULTS: We observed 11 hemoptyses (7.4%), 10 were lethal. All but one occurred in patients with progressive disease. Two clinical factors were significantly associated with hemoptysis by univariate analysis: palliative group (p=0.009) and endobronchial tumor length (p=0.004). No technical factors seem to be implicated in the occurrence of hemoptysis. Only endobronchial tumor length remained in the multivariate model (p=0.02). Radiation bronchitis was observed in 13 cases (8.7%). By univariate analysis, a good Karnofsky score (p=0.02), curative treatment (p=0.02), and tumor location on trachea and main stem bronchus (p=0.002) were significantly associated with this complication. Two technical factors were also incriminated: the total dose (p=0.04) and the 100% isodose volume (p=0.02). By multivariate analysis, only the tumor location retained statistical significance (p=0.009). CONCLUSION: Hemoptysis is most likely due to disease progression, with the bleeding being facilitated by brachytherapy. Some rare cases could be a direct complication of brachytherapy itself, particularly when tumors are located in the upper lobes. In contrast, radiation bronchitis occurred more frequently in patients with controlled disease, and was significantly influenced by tumor location and technical factors (dose and volumes treated). Technical improvements should increase the therapeutic ratio.

Analysis of Variance↗
PubMed1997

[Postoperative radiotherapy in non-small cell lung cancer. Apropos of a series of 374 cases].

PURPOSE: Several randomized trials have led us to address the usefulness of post-surgical external beam therapy (EBT) in non-oat cell bronchial carcinoma. Results that were obtained in a group of 374 patients submitted between 1977 and 1994 to identical therapy-the follow-up being done by the same team-and results of six randomized trials are analyzed. PATIENTS AND METHODS: The tumor stages were the following: T1, 13%; T2, 56%; T3, 29%; and T4, 2%; N0, 31%; N1, 34%; and N2, 35%. There were 85% histologically complete resections. EBT was administered according to either the classical irradiation scheme (C) or as an 'equivalent hypofractionated dose' (H) in the case of complete resection. When resection was not complete, 60 to 65 Gy were administered according to a C or an H irradiation scheme. The irradiation scheme was C in 73% of the cases and H in 27%. The EBT technique has been chosen to ensure maximum lung sparing. Following a 45 Gy-irradiation with anteroposterior beams, orthogonal or, when necessary, oblique beams were used. Non homogeneity of the lungs was taken into account in establishing the treatment planning. The treatment file was collectively checked by the medical staff in 75% of the cases. EBT was indicated for N+(N1+N2), T3 and incomplete resections. RESULTS: The overall survival was 42% at 5 years and 27% at 10 years. The 5-year survival was 52% for stage I cancer (T1N0-T2N0), 60% for stage II cancer (T1N1-T2N1), 31% for stage IIIa cancer (T3N0, T1-3N2), 45% for complete resection and 30% when resection was not complete. CONCLUSION: Regarding the benefits of post-surgical radiotherapy, the analysis of the six randomized trials does not allow any conclusion. This might be due to either the insufficient number of cases, a follow-up time not long enough, incorrect radiotherapy, or insufficient available data. Comparison of the results pertaining to the six trials with those of our series shows an advantage for the current series, indicating that survival is likely to be improved if EBT is correctly done with regard to the dose, volume and technique used.

Actuarial Analysis↗
PubMed1995

[Treatment of bronchial tumors with high-frequency thermocoagulation. Preliminary studies].

Several techniques are available for endobroncheal tissue destruction. The cost and nature of the effect of the different techniques are determining factors in deciding on which equipment to use. Electrocoagulation is an old method which has practically been abandoned in favour of high frequency coagulation. This technique has an immediate effect, somewhat like the laser. We treated 32 patients with inoperable malignant (17) or benign (5) tumours obstructing the trachea or the bronchi. Response to treatment was evaluated on clinical manifestations and endoscopic findings. Haemostasis was obtained in 11/12 cases and tumour destruction of more than 50% in 27/32 cases. Complications included haemoptysia in 2 patients followed by death due to respiratory failure in 1. The ERBOTOM ACC 450 equipment was piloted with a microcomputer to control the power output automatically. White coagulation was induced by slow heating up to 70-100 degrees C causing tissue vaporization. The cost of this multiple applications of this equipment is competitive.

Adult↗
PubMed1995

Cryotherapy for tracheobronchial disorders.

Cryotherapy is the therapeutic application of extreme cold for local destruction of living tissue. This technique has been shown to be effective and safe in treating endobronchial lesions, particularly in patients with endobronchial carcinoma and airway obstruction. This article describes cryotherapy and its use in treating tracheobronchial disorders.

Animals↗
PubMed1994

The operation and efficacy of cryosurgical, nitrous oxide-driven cryoprobe. I. Cryoprobe physical characteristics: their effects on cell cryodestruction.

For specification of the requirements for efficient cell cryodestruction in tumors, we tested a N2O-driven cryoprobe on experimental models. The cryoprobe was a 3-mm-diameter type for operation via fiber optic bronchoscopes in respiratory medicine. The freezing process, namely the "ice-ball" formation around the cryoprobe tip, was monitored with an impedancemeter. Physical characteristics and formation kinetics of the ice-ball formation (volume, diameter, freezing rate) were studied under defined experimental conditions in various biological liquids, including saline, serum, whole blood, and tumor cell suspensions (rat ascitic hepatoma), either plain or supplemented with gelling agents to approximate solid tumor consistency. Cell destruction (i.e., cryotoxicity to cells) within the ice ball produced in rat ascitic hepatoma was assessed in two ways: the cells, collected after ice-ball thawing, were (1) seeded and cultured according to methods currently in use, or (2) injected into a rat to check for possible development of ascites. Both tests showed that cryotoxicity correlated with freezing rate within the ice ball, cell mortality was total next to the cryoprobe tip (i.e., site of highest freezing rate), while it was absent within the ice-ball periphery. In the area in between, mortality varied gradually. Together our experimental results show that cryotoxicity to cells may be improved by increasing the freezing rate (e.g., by brief precooling of the cryoprobe). Furthermore, for tumor cryosurgery, since cell mortality is maximal next to the cryoprobe, we point out that higher efficacy might be achieved by several overlapping short freezing spots in tumoral tissue, instead of one single prolonged freeze.

Animals↗
PubMed1994

Prolonged survival after high-dose rate endobronchial radiation for malignant airway obstruction.

STUDY OBJECTIVE: To show that prolonged survival can be observed after high-dose rate (HDR) endobronchial brachytherapy as the sole treatment for some selected patients presenting with an endobronchial malignant obstruction. PATIENTS: Twenty-nine patients (group 1) who presented with an endoluminal localized tumor without metastatic extension were treated by HDR endobronchial brachytherapy and are compared with 22 subjects who presented with extraluminal dissemination and were palliatively treated (group 2). TREATMENT PROTOCOL: Treatment consisted of sessions of two exposures, delivering 7 Grays at a 10-mm radius from the center of the applicator each, and repeated every 15 days, to a maximum of six exposures. Endoscopic response and survival are the main criteria of assessment. RESULTS: Follow-up bronchoscopies, performed 2 months after the end of the procedure, showed tumor regressions: macroscopic complete responses (CR) were observed in 21 of 25 patients evaluable in group 1, and 6 of 22 in group 2, with histologic CR in 18 and 2 patients, respectively. Median overall survival was not reached in group 1 after 23 months of follow-up; it was 5 months for group 2. CONCLUSIONS: These results confirm that HDR brachytherapy can be used as a monotherapy for carefully selected patients who have small tumors to all appearances limited to the bronchial lumen and bronchial wall without adjacent parenchymal extension or metastatic disease.

Airway Obstruction↗
PubMed1992

Tumor fixation of bleomycin labeled with 57 cobalt before and after cryotherapy of bronchial carcinoma.

The combined effect of cryotherapy and chemotherapy was studied in 12 patients with bronchial carcinoma. Radiolabeled (57 Co) Bleomycin (BLM) was injected intravenously and initial detection was carried out with a gamma-camera. Plasma half-life and clearance of 57 Co-BLM, as well as tumor/normal tissues ratios were calculated. The same protocol was performed 15 days later immediately after cryotherapy. A mean increase of 30% of radiolabeled BLM was found in the tumor area after cryotherapy, and pharmacokinetic data were significantly different after cryotherapy. The vascular component of cryodestruction offers an explanation for these results, with trapping of the anticancer drug in the tumor and immediately surrounding area due to vascular stasis. It seems that chemotherapy may be more effective after cryotherapy, and a multicenter study is in progress to evaluate the association of cryo-chemotherapy in France.

Adenocarcinoma↗
PubMed1992

[Reevaluation of environmental factors in allergy to mites: bedding not a factor?].

Prospective multicentric study was conducted among parents of children referred in three allergy units. Unlike current opinions: carpets are less frequent in bedrooms of mite's allergic children. foam bedding don't play any role, local humidity non significantly increases the mite's allergy risk. the sunlight absence is significantly correlated with this hypersensitivity. These data, mainly inconsistent with general conviction, could be explained by socio economic diversity of patients.

Allergens↗
PubMed1992

[Allergy: the pressing need for public education].

Data collected using a self-questionnaire filled out by the families of 294 children under 12 years of age seen in a pneumoallergology clinic showed widespread lack of information on the role of environmental factors in allergic diseases. Parents ascribed their child's disease to the environment at home only when they were dissatisfied by their housing conditions. Parents who were satisfied with their home failed to perceive that indoor factors with detrimental effects may nevertheless be present. This lack of information was seen across the spectrum of enrolled patients, including in those with hypersensitivity to house mites. The need for health education of the public at large aimed at promoting preventive strategies is underlined.

Allergens↗