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F Reboul

Publications and source records attributed to F Reboul.

At least 19 recordsLinked to original sources
PubMed2004

[Recommendations in the use of portal images].

Technical radiotherapy progress drive the practices towards increasingly more precise irradiations. The recent developments of the various imaging methods and specialized software made more controls possible. The fields of investigations relate to the quality assurance of the irradiation, the reproducibility of positioning, the movements evaluations and real time dosimetry. Radiotherapy finds, in the images exploitation, a strong potential in improving quality treatments, however it is conditioned by the implementation of ambitious programs, time consuming, but essential to grant the precision of virtual simulations and the daily practice. If all the existing technical devices and software offer higher tools than the current practices, the recommendations can be limited to the insurance of a sufficient precision and reproducibility of the whole treatments. It is thus fundamental to be able to filter the errors, the systematic deviations and to control the statistics of positioning and movements. Each radiotherapy department must apply an adapted program to each site and exploit the imaging chain to maintain its results.

Humans↗
PubMed2003

[Dose-response relationship in radiotherapy: an evidence?].

The dose-response relationship is a fundamental basis of radiobiology. Despite many clinical datas, difficulties remain to demonstrate a relation between dose and local control: relative role of treatment associated with radiation therapy (surgery, chemotherapy, hormonal therapy), tumor heterogeneity, few prospective randomized studies, uncertainty of local control assessment. Three different situations are discussed: tumors with high local control probabilities for which dose effect is demonstrated by randomized studies (breast cancer) or sound retrospective datas (soft tissues sarcomas), tumors with intermediate local control probabilities for which dose effect seems to be important according to retrospective studies and ongoing or published phase III trials (prostate cancer), tumors with low local control probabilities for which dose effect appears to be modest beyond standard doses, and inferior to the benefit of concurrent chemotherapy (lung and oesophageal cancer). For head and neck tumors, the dose-response relationship has been explored through hyperfractionation and accelerated radiation therapy and a dose effect has been demonstrated but must be compared to the benefit of concurrent chemotherapy. Last but not least, the development of conformal radiotherapy allow the exploration of the dose response relationship for tumors such as hepatocellular carcinomas traditionally excluded from the field of conventional radiation therapy. In conclusion, the dose-response relationship remains a sound basis of radiation therapy for many tumors and is a parameter to take into account for further randomized studies.

Adult↗
PubMed2003

[Respiration-gated radiotherapy: current techniques and potential benefits].

Respiration-gated radiotherapy offers a significant potential for improvement in the irradiation of tumor sites affected by respiratory motion such as lung, breast and liver tumors. An increased conformality of irradiation fields leading to decreased complications rates of organs at risk (lung, heart...) is expected. Respiratory gating is in line with the need for improved precision required by radiotherapy techniques such as 3D conformal radiotherapy or intensity modulated radiotherapy. Reduction of respiratory motion can be achieved by using either breath hold techniques or respiration synchronized gating techniques. Breathhold techniques can be achieved with active, in which airflow of the patient is temporarily blocked by a valve, or passive techniques, in which the patient voluntarily breath-hold. Synchronized gating techniques use external devices to predict the phase of the respiration cycle while the patient breaths freely. These techniques presently investigated in several medical centers worldwide. Although promising, the first results obtained in lung and liver cancer patients require confirmation. Physical, technical and physiological questions still remain to be answered. This paper describes the most frequently used gated techniques and the main published clinical reports on the use of respiration-gated radiotherapy in order to evaluate the impact of these techniques.

Breast Neoplasms↗
PubMed2002

[Radiotherapy of lung cancer: the inspiration breath hold with spirometric monitoring].

A CT acquisition during a free breathing examination generates images of poor quality. It creates an uncertainty on the reconstructed gross tumour volume and dose distribution. The aim of this study is to test the feasibility of a breath hold method applied in all preparation and treatment days. Five patients received a thoracic radiotherapy with the benefit of this procedure. The breathing of the patient was measured with a spirometer. The patient was coached to reproduce a constant level of breath-hold in a deep inspiration. Video glasses helped the patients to fix the breath-hold at the reference level. The patients followed the coaching during preparation and treatment, without any difficulty. The better quality of the CT reconstructed images resulted in an easier contouring. No movements of the gross tumour volume lead to a better coverage. The deep breath hold decreased the volume of irradiated lung. This method improves the reproducibility of the thoracic irradiation. The decrease of irradiated lung volume offers prospects in dose escalation and intensity modulation radiotherapy.

Aged↗
PubMed2002

[Prostate cancer: has local radiation treatment had an impact on survival?].

Local control is an important goal in the treatment of prostate cancer. Firstly, it avoids the morbidity due to locoregional evolution (urethral obstruction, vascular compression, rectal or vesical involvement). Moreover, local control of the disease may decrease the mortality due to metastases disseminated from local relapse. Local control evaluation remains difficult: neither rectal examination nor imaging or prostate biopsies have an absolute value in diagnostic of local relapse. PSA increase does not permit to differentiate local from distant relapses. Recent developments in radiotherapy techniques allow dose escalation without major toxicity. Retrospective studies and one randomized study have shown that an increase from 70 to 80 Gy or more, improve biological relapse-free survival. In one randomized study comparing 70 to 78 Gy, the biochemical disease-free survival was improved from 69 to 79% at five years. Such an improvement can only be explained by an improvement of local control. The benefit in term of overall survival is not yet demonstrated and needs a longer follow-up and other studies. Another approach to improve local control is the association of a local radiotherapy with hormonal adjuvant therapy. Four randomized studies have been published for locally advanced prostate cancer. These studies have all demonstrated an improvement of local control, and a decrease of metastatic risk. The benefit in term of overall survival, observed in one of this trial, may be explained by the improvement of either local or distant control or both. Such therapeutic progress, associated with the development of prostate cancer screening should lead to a decrease of prostate cancer mortality for the next ten years.

Adenocarcinoma↗
PubMed2002

[Thoracic radiotherapy and control of respiration: current perspectives].

Three-dimensional conformal radiotherapy (3D CRT) is adversely affected by setup error and organ motion. In thoracic 3D CRT, breathing accounts for most of intra-fraction movements, thus impairing treatment quality. Breath control clearly exhibits dosimetric improvement compared to free breathing, leading to various techniques for gated treatments. We review benefits of different breath control methods--i.e. breath-holding or beam gating, with spirometric, isometric or X-ray respiration sensor--and argument the choice of expiration versus inspiration, with consideration to dosimetric concerns. All steps of 3D-CRT can be improved with breath control. Contouring of organs at risk (OAR) and target are easier and more accurate on breath controlled CT-scans. Inter- and intra-fraction target immobilisation allows smaller margins with better coverage. Lung outcome predictors (NTCP, Mean Dose, LV20, LV30) are improved with breath-control. In addition, inspiration breath control facilitates beam arrangement since it widens the distance between OAR and target, and leaves less lung normal tissue within the high dose region. Last, lung density, as of CT-scan, is more accurate, improving dosimetry. Our institution's choice is to use spirometry driven, patient controlled high-inspiration breath-hold; this technique gives excellent immobilization results, with high reproducibility, yet it is easy to implement and costs little extra treatment time. Breath control, whatever technique is employed, proves superior to free breathing treatment when using 3D-CRT. Breath control should then be used whenever possible, and is probably mandatory for IMRT.

Artifacts↗
PubMed2001

[Are there physical, technical and morphological limits to conformational radiotherapy?].

Conformal radiotherapy results from several technical and data processing advances. The treatment planning and the daily treatments have benefited from a significant improvement of the quality control. However, all the steps of the process contain various limitations of varying effects. It appear important to identify, describe and exploit those limits to better drive the procedures and optimise the quality. Identifying the limits of the conformal radiotherapy should be an important help to implement intensity modulation radiotherapy.

Anthropometry↗
PubMed2000

[Radiotherapy of localized prostatic cancer: follow-up of 48 patients. G.C.C.P. (Cooperative Group for the Study of Prostatic Cancer)].

OBJECTIVE: To evaluate the safety and long-term efficacy of curative-intent radiation therapy in patients with apparently localized prostate cancer. METHOD: 48 patients with T < 3 M0 prostate cancer recruited between 1981 and 1985 received regular clinical follow-up for at least ten years or until their death. Radiation therapy was given according to the protocols established by Ray and Bagshaw. RESULTS: Radiation therapy was safe and effective in most patients. The rate of escape phenomenon was less than 10% after two years. Tumor control rates were greater than 80% after five years and 50% after ten years. Unfortunately, local remission, even when prolonged, did not necessarily indicate a complete cure: 20% of local recurrences developed five to 11 years after radiation therapy. CONCLUSION: Radiation therapy may be the best first-line treatment in men older than 75 years of age and in those whose life expectancy seems shorter than ten years, but should probably not be considered curative.

Aged↗
PubMed1999

[Endobronchial brachytherapy].

Endobronchial brachytherapy was developed following the miniaturization of radio-active sources enabling the use of fiberoptic techniques to deliver treatment at high dose yet substantially reducing the duration of treatment. Endobronchial brachytherapy has been used in patients presenting with symptomatic obstruction of the proximal bronchial tree in association with laser therapy. The level of responses in these palliative indications is around 80 per cent. Currently, other investigations are undergoing evaluation to test the method in association with conventional treatment to determine whether brachytherapy can augment local control. In the treatment of small tumours when other conventional treatments are not possible brachytherapy employed alone has shown undoubted efficacy. However there remain numerous problems to resolve: what is the ideal protocol in terms of total dose, dose per fraction, the order of dosing and fractions? How can secondary complications to endoluminal irradiation be limited in particular for curative therapy. An answer should be found for all these questions before this technique is eventually integrated into the primary treatment regimes for bronchial cancer.

Brachytherapy↗
PubMed1998

High dose rate endobronchial brachytherapy: results and complications in 189 patients.

The purpose of this study was to determine the benefit of high dose rate endobronchial brachytherapy in the treatment of obstructive lung cancer. Between September 1990 and March 1995, 189 patients with bronchogenic carcinoma were treated with high dose rate endobronchial brachytherapy. Most patients (69.3%) had received prior treatment and presented with symptomatic bronchial obstruction due to either recurrent or residual endobronchial disease. A small group (12%) was medically unfit for either surgical resection or thoracic radiotherapy and benefited from endobronchial brachytherapy alone for small endobronchial tumours. The remainder of the patients had not been treated previously and endobronchial brachytherapy was performed for life-threatening symptoms requiring emergency obstruction relief before other therapy. Treatment was performed weekly and consisted of three to four 8 to 10 Gy fractions at a radius of 10 mm from the centre of the source. Major symptomatic relief was obtained for haemoptysis (74%), dyspnoea (54%), and cough (54%). Complete endoscopic response was observed in 54% of cases. Median survival was 7 months for the entire group. For small, strictly endobronchial tumours, complete response rate was 96%, median survival 17 months, and 30 month survival 46%, with a plateau starting at 18 months. Grade 3 to 4 toxicities occurred at a rate of 17% and included massive haemoptysis (n=13), bronchial stenosis (n=12), soft tissue necrosis (n=8), and bronchial fistula (n=3). By univariate analysis, no factor was found to be predictive of late pulmonary toxicity. The present study confirms the usefulness of endobronchial brachytherapy in alleviating symptoms caused by endobronchial recurrence of bronchogenic carcinoma. In addition, this therapy can be tried with curative intent in patients who present with small endobronchial tumours and are not candidates for other forms of therapy.

Adult↗
PubMed1998

[Treatment of infiltrating cancer of the bladder with cisplatin, fluorouracil, and concurrent radiotherapy: results of a pilot study].

PURPOSE: Pilot study to assess treatment feasibility and results of a 2-drug chemotherapy (CT) regimen administered concurrently with radiotherapy (RT) for muscle-invasive bladder cancer. MATERIALS AND METHODS: Fourty-six patients were included into a prospective study from December 1992 to April 1996. The median age was 66 years. Thirty-seven percent of the patients had T3B-T4 tumors, and 46% had benefited from prior macroscopically complete transurethral resection (TUR). Pelvic irradiation consisted of 50.4 Gy in 28 fractions over 39 days. Concurrent CT consisting of cisplatin (80 mg/m2/d1) and 5-fluorouracil (800 mg/m2/d2 to 5) by continuous infusions (5-FU) was delivered during the first and fifth weeks of radiation therapy. Twenty-three patients received two additional courses of adjuvant CT with cisplatin, methotrexate and vinblastin (MCV). RESULTS: The median follow-up was 38 months. The feasibility of concurrent CT-RT was excellent: 96% of the patients completed radiotherapy and 100% of them received the two courses of P-FU. The acute toxicity was mild: no hematological toxicity or renal toxicity over grade II, 4 cases of bowel or rectal reversible grade III toxicity and 2 cases of reversible grade III cystitis. A complete response was achieved in 30 out of the 42 evaluable patients (65.2%). Nine patients received an immediate salvage treatment (3 TUR, 3 additional radiotherapy and 3 cystectomies). Ten patients had local failure. Projected 3-year locoregional control was 49% for the 46 patients. Projected overall 3-year survival was 53%. Functional results were good for disease-free patients with preserved bladder: 1 grade I, 3 grade II, and no grade III cystitis. CONCLUSION: Concurrent 2-drug chemoradiotherapy with cisplatin and 5-fluorouracil is feasible without major toxicity and offers a potentially curative and conservative treatment for patients with localized muscle-invasive bladder cancer.

Aged↗
PubMed1998

[Results of long-term treatment of inoperable cancer of the bladder with cisplatin and concurrent irradiation: prognostic factors of local control and survival].

PURPOSE: Therapeutic strategies for muscle invasive bladder cancer are currently evolving. A recent European randomized study has shown that neoadjuvant chemotherapy does not improve the chance of cure or and radiotherapy would provide better results but there is a need to identify by prognostic factors patients who may benefit from such a conservative strategy. MATERIAL AND METHODS: One hundred and nine patients with localized muscle-invasive bladder cancer, who were not candidates for radical cystectomy, were treated with concomitant cisplatin and radiation therapy. Their mean age was 71. Thirty-six percent of the patients had T3B-4 tumors, and 37% had benefited from prior macroscopically complete transurethral resection (TUR). Pelvic irradiation consisted of 40 to 45 Gy and was followed by a boost to the bladder to a total dose of 55 to 60 Gy. Continuous infusion cisplatin (20 to 25 mg/m2/d for 5 days) was delivered during the second and fifth weeks of radiation therapy. RESULTS: Median follow-up was 73 months. The projected 5-year locoregional control rate was 43% for the 109 patients and 55% for the 86 patients with complete response. The projected overall 5-year survival rate was 36% for all patients and 44% for complete responders. Univariate analysis of prognostic factors was carried out for local control, and survival. The local control was statistically better in patients with good performance status, T2-3A, complete initial TUR, and in patients without hydronephrosis. In terms of overall survival, four factors were significant: the performance status, T-stage, absence of hydronephrosis, and complete response. By multivariate analysis, performance status, hydronephrosis and T-stage were significant factors for local control, while T-stage and complete response were the strongest determinants for survival. CONCLUSION: Concurrent cisplatin and radiation therapy is a potentially locally curative treatment for 43% of patients with muscle-invasive bladder cancer not candidates for radical surgery. Clinical T-stage and hydronephrosis have a significant and independent prognostic value on local control but appears not discriminant enough to select patients for conservative treatment.

Adult↗
PubMed1997

[Concomitant radiochemotherapy with cisplatin-etoposide with or without surgery in stage III non-small cell lung cancers: results of a pilot study in 67 patients].

PURPOSE: This pilot phase II study was aimed at determining the feasibility, toxicity, response rate, local control, and survival of concomitant chemotherapy with cisplatin-etoposide and radiotherapy in stage IIIA or IIIB non small-cell lung cancer (NSCLC). PATIENTS AND METHODS: Between February 1992 and February 1994, 67 patients with either medically or technically inoperable stage III NSCLC were treated with concomitant chemoradiotherapy. Thoracic radiotherapy was administered to a median dose of 60 Gy over 6 weeks. Concomitant chemotherapy consisted of cisplatin 20 mg/m2/day plus etoposide 50 mg/m2/day from day 1 to day 5, every 4 weeks over four cycles. Medically operable patients were evaluated for surgical resection after a 45-Gy irradiation and two cycles of concomitant chemotherapy. Only 14 patients could undergo subsequent surgery. RESULTS: With a median 49-month and a minimum 34-month follow-up, the overall survival rate was 42% at 2 years, and 34% at 4 years. The median survival was 19 months and the actuarial local control rate was 57% at 3 years. Toxicity was mainly associated with myelosuppression and esophagitis, but could be treated and was of short duration. CONCLUSION: Concomitant chemoradiotherapy with cisplatin and etoposide at this dose level provides a well tolerated outpatient regimen that results in high local control rate and encouraging survival at 2.4 years. A similar regimen is being compared in a phase III trial including induction chemotherapy followed by radiotherapy.

Adult↗
PubMed1997

[Conformational radiotherapy in cancers of the prostate: contribution of pelvic immobilization and new fiducial markers].

PURPOSE: To reduce errors in the positioning of patients treated with external conformal radiotherapy for prostate cancer, we evaluated both the use of an immobilization device and new fiducial markers. MATERIALS AND METHODS: The immobilization device consisted of an individual mold made of polyurethan foam. Two sets of skin markers located on the anterior tibial surfaces were used to identify the pelvic isocenter. The patient's position was evaluated by orthogonal port films which were then compared with the original simulation film. RESULTS: Results are presented with respect to orthogonal axes. Comparison with classic procedures without immobilization showed that use of the mold and new fiducial markers led to a decrease in set-up errors which were less than 5 mm. CONCLUSION: With the use of an immobilization device and optimized techniques for patients' positioning, conformal radiotherapy of prostate cancer is more accurate.

Computer Simulation↗
PubMed1997

[Concomitant radiochemotherapy for locally advanced bronchial cancers: current results and prospects].

The prognosis of locally advanced lung cancer is reportedly poor in all histologic types. In non-small cell lung cancer, radiation therapy alone results in disappointing long-term survival. Three recent randomized trials, however, have shown a limited but significant improvement of survival with induction chemotherapy, though local control remained poor in these studies as well as in small-cell lung cancer treated with chemotherapy and late radiotherapy. Two randomized trials focusing on small-cell lung cancer have recently shown significant benefit due to the combination of early concurrent mediastinal irradiation and chemotherapy, with major improvement in local control and a more than 40% 2-year survival rate. The concept of concurrent chemoradiotherapy has also been studied in non-small cell carcinoma with several pilot studies leading to both encouraging results and improved survival rate (up to 40% at 2 years). Ongoing phase III trials are comparing sequential versus concurrent chemoradiotherapy and will define the role of radical surgery after chemoradiotherapy in locally advanced non-small cell lung cancer.

Antineoplastic Combined Chemotherapy Protocols↗
PubMed1997

[Adjuvant combined radiochemotherapy: a feasibility study of a new strategy in stages I and II].

Adjuvant radiotherapy is the rule after conservative surgery for breast cancer. Furthermore, an anthracycline-based chemotherapy is recommended in node-positive patients and in poor prognosis tumors. The optimal schedule of treatment has yet to be determined, but ideally, none of these therapeutic modalities should be delayed. We have therefore conducted a feasibility trial using post-operative concurrent chemoradiation therapy with an anthracenedione. Between May 1990 and October 1994, 154 patients with stage I or II breast cancer who had benefited of either limited or radical surgery were treated with adjuvant concurrent chemoradiotherapy. Radiotherapy consisted of 50 Gy in 25 fractions over 5 weeks to the chest wall or the breast, and to the supraclavicular and internal mammary lymph nodes. When indicated, a boost of 15 Gy was then delivered to the primary tumor bed (n = 75). Starting on the first week of radiotherapy, combined chemotherapy with 5-fluorouracil, mitoxantrone, and cyclophosphamide was administered at 21-day intervals, for 4 to 6 cycles. Compliance to therapy was excellent. Median radiotherapy dose was 49.5 Gy to the chest wall or breast, and to the lymph nodes, and 14.2 Gy to the tumor bed. Chemotherapy was given at full dose in over 80% of the cases and the 21-day interval between cycles was respected in 31%. In 45% of the cases, a 28-day interval was required due to toxicity, and at least one interval longer than 28 days was necessary in the remainder of the patients. Main toxicities were nausea and vomiting (20.8%) and grade 3-4 neutropenia (12.3%). Grade 1 cutaneous toxicity occurred in 62.3% of the cases, and severe grade 3 radiation dermatitis requiring temporary interruptions of therapy in 4.5%. With the exception of one case of grade 3 acute cardiac toxicity, there was no other severe side-effects. In conclusion, this pilot study demonstrates the feasibility of concurrent chemoradiation therapy with an anthracenedione for stage I and II breast cancer in the adjuvant setting. Whether this approach compares favorably with standard sequential therapy in terms of long-term results remains to be determined and should be assessed in a phase III trial.

Adult↗