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C Carrie

Publications and source records attributed to C Carrie.

At least 19 recordsLinked to original sources
PubMed2003

Conformal irradiation for pure and mixed oligodendroglioma: the experience of Centre Leon Berard Lyon.

PURPOSE: To assess whether conformal radiotherapy (CRT) after incomplete surgery or biopsy for pure oligodendrogliomas and mixed gliomas results in decreased long-term sequelae without impairing local control and while reducing irradiated volume. MATERIALS AND METHODS: Twenty-six consecutive patients who presented with pure (21) or mixed (5) oligodendrogliomas and who were given incomplete resections were treated according 3 different strategies: CRT alone (12), chemotherapy followed by CRT (4), and chemotherapy and delayed CRT at the time of tumor progression (10). CRT consisted of multiple noncoplanar fields. Median dose was 60 Gy. Quality of CRT was assessed using tumor and normal tissue conformal indexes. The location of recurrences was assessed with MRI and dosimetric data. Late sequelae were assessed by a questionnaire exploring professional outcome, and also by a Mini Mental State Examination test. RESULTS: The mean overall survival was 5.2 years. Fifteen patients experienced a local relapse. All but 1 occurred in the 95% isodose. Among 11 nonevolutive patients, 6 have a full-time or part-time job. CONCLUSIONS: Despite CRT, infield recurrence was a common feature in patients with oligodendrogliomas and mixed tumors. Further research, including molecular biology typing of tumors and type of treatment, is warranted to improve survival and quality of life.

Adult↗
PubMed2002

Comparison of manual and computer-generated customized blocks for whole brain fields used in the treatment of medulloblastoma.

BACKGROUND: By using CT simulation and three-dimensional planning, we have developed a simple but accurate method of producing customized blocks for the cranial fields in the treatment of medulloblastoma. We compare here the margins and the volume of normal tissues included in the treatment volume with those obtained using blocks generated manually. PROCEDURE: Customized blocks for the whole brain field are generated using CT planning and autoblock function. The clinical target volume (CTV) is defined as the whole cerebrospinal fluid pathway, and the whole brain and spinal cord are contoured. A margin of 1.1 cm is generated using the autoblock function to account for set-up errors (3-5 mm) and penumbra (approximately 7 mm). A separate set of blocks was generated manually without the knowledge of the ones generated by the CT-simulator. These 2 sets of blocks were compared for a cohort of 7 consecutive patients. RESULTS: Overall, the manual blocks and the computer-generated blocks were quite similar. Those generated manually had more variations; they were always tighter (median of 6 mm tighter; range: 3-7 mm) at the level of the cribriform plate and in 5/7 patients were more generous (median of 6 mm more generous, range: 0-6 mm) at the temporal lobes. Dosimetric analysis showed that both methods provide adequate coverage of the CTV, with 100% of the CTV receiving > 95% of the prescribed dose for both. CONCLUSIONS: The customized block method for whole brain fields is simple to use and ensures adequate coverage of the target volume.

Cerebellar Neoplasms↗
PubMed2002

[Target-volume and critical-organ delineation for conformal radiotherapy of prostate cancer: experience of French dose-escalation trials].

The delineation of target volume and organs at risk depends on the organs definition, and on the modalities for the CT-scan acquisition. Inter-observer variability in the delineation may be large, especially when patient's anatomy is unusual. During the two french multicentric studies of conformal radiotherapy for localized prostate cancer, it was made an effort to harmonize the delineation of the target volumes and organs at risk. Two cases were proposed for delineation during two workshops. In the first case, the mean prostate volume was 46.5 mL (extreme: 31.7-61.3), the mean prostate and seminal vesicles volume was 74.7 mL (extreme: 59.6-80.3), the rectal and bladder walls varied respectively in proportion from 1 to 1.45 and from 1 to 1.16; in the second case, the mean prostate volume was 53.1 mL (extreme: 40.8-73.1), the volume of prostate plus seminal vesicles was 65.1 mL (extreme: 53.2-89), the rectal wall varied proportionally from 1 to 1, 24 and the vesical wall varied from 1 to 1.67. For participating centers to the french studies of dose escalation, a quality control of contours was performed to decrease the inter-observer variability. The ways to reduce the discrepancies of volumes delineation, between different observers, are discussed. A better quality of the CT images, use of urethral opacification, and consensual definition of clinical target volumes and organs at risk may contribute to that improvement.

Adenocarcinoma↗
PubMed2002

[Treatment of bronchial carcinoma in the elderly].

Elderly patients form an increasing proportion of the lung cancer population. However, they are poorly represented in clinical trials. The published studies are generally phase II trials on highly selected small numbers of patients. Applying these trials to clinical practice is therefore difficult and this is compounded by the fear of increased treatment toxicity in elderly patients. In the event of organ failure (respiratory, cardiac or other organ failure), where conventional therapy is not possible, there are a number of alternative options: radiotherapy for inoperable limited non-small-cell-lung cancer, chemotherapy without platinum for those with more extensive disease or with analogues of platinum for small-cell-lung-cancer. Finally, adjunctive therapy with haematopoietic-cell growth factors or cytoprotectors may allow full doses of treatment to be delivered whilst limiting toxicity. More studies in elderly patients, with larger numbers, are needed to develop more rational therapeutic strategies. We present here some studies of reference and the most recent publications on this subject.

Age Factors↗
PubMed2001

Prognostic factors in localized Ewing's tumours and peripheral neuroectodermal tumours: the third study of the French Society of Paediatric Oncology (EW88 study).

PURPOSE: (1) To improve survival rates in patients with Ewing's sarcoma (ES) or peripheral neuroectodermal tumours (PNET) using semi-continuous chemotherapy and aiming to perform surgery in all; (2) To identify early prognostic factors to tailor therapy for future studies. PATIENTS AND METHODS: One hundred and forty-one patients were entered onto the trial between January 1988 and December 1991. Induction therapy consisted of five courses of Cytoxan, 150 mg/m(2) x 7 days, followed by Doxorubicin, 35 mg/m(2) i.v on day 8 given at short intervals. Surgery was recommended whenever possible. The delivery of radiation therapy was based on the quality of resection and the histological response to CT. Maintenance chemotherapy consisted of vincristine + actinomycin and cytoxan + doxorubicin. The total duration of therapy was 10 months. RESULTS: After a median follow-up of 8.5 years, the projected overall survival at 5 years was 66% and disease-free survival (DFS) was 58%. In patients treated by surgery, only the histological response to CT had an influence on survival: 75% DFS for patients with a good histological response (less than 5% of cells), 48% for intermediate responders and only 20% for poor responders (> or = 30% of cells), P < 0.0001. The initial tumor volume by itself had no influence on DFS in these patients. In contrast, the tumour volume had a strong impact on DFS in patients treated by radiation therapy alone. Age had no impact on outcome. CONCLUSION: Therapeutic trials for localized Ewing's sarcoma should be based on the histological response to chemotherapy or on the tumour volume according to the modality used for local therapy.

Adolescent↗
PubMed2001

Osteosarcoma.

Explore the source record for details and available documents.

Bone Neoplasms↗
PubMed2001

[Multicenter study on dose escalation with conformal and conventional radiotherapy for the treatment of localized prostatic cancer. Preliminary results of tolerance and quality of life].

OBJECTIVE: To study the safety of conformal radiotherapy dose escalation up to 80 Gy for curative treatment of prostate cancer. MATERIAL AND METHODS: A multicentre trial sponsored by the PHRC include 164 patients under the age of 75 years with stage T1b-T3 N0 M0 prostatic adenocarcinoma, between 1995 and 1998. The prostate was treated at 5 dose levels: 18 patients at 66 Gy, 28 at 70 Gy, 49 at 74 Gy, 48 at 78 Gy, 21 at 80 Gy. The acute and delayed toxicity was graded according to a multidisciplinary glossary. Quality of life was evaluated before and one year after treatment using the EORTC QLQ-C30 questionnaire and additional questions. RESULTS: 89% and 55% of mild or moderate gastrointestinal and urinary adverse effects were observed during treatment, respectively. At long-term follow-up, of the 162 evaluable patients, 12.3% presented grade 2 adverse effects and 2.5% presented grade 3 adverse effects (1 case of haematuria, 2 urethral strictures, 1 bladder neck lesion) with no significant difference between the various dose levels. Two successive quality of life questionnaires were available for 119 patients: tiredness, pain and dyspnoea increased in parallel, but non-significantly in the groups receiving conventional doses or high doses. The proportion of patients reporting sexual activity without endocrine therapy decreased from 48% before treatment to 35% one year later. The proportion of patients with no clinical or laboratory signs of progression was higher in the high-dose group. CONCLUSION: No significant difference was observed between conventional dose levels and high dose levels in terms of toxicity or quality of life. As the adverse effects were acceptable, a randomized trial comparing 70 Gy and 80 Gy has been initiated.

Adenocarcinoma↗
PubMed2001

[Is conformational radiotherapy progressing? What are its difficulties and limits?].

Increase local control rate is the main objective of 3D conformal radiotherapy (3DCRT) through sparing surrounding tissues and more precise target volume irradiation. Limits are however present for each step of the procedure (immobilisation device, anatomical data acquisition, dose calculation and optimisation, treatment verification and execution). Dose distribution is clearly better with 3DCRT and allows dose escalation. However, clinical data comparing irradiation techniques are rare and do not allow to consider yet 3DCRT as a standard treatment. Medical and medico-economical studies are warranted both for 3DCRT and IMRT in order to prove their utility and justify their cost.

Costs and Cost Analysis↗
PubMed2000

A study of dose delivery in small segments.

PURPOSE: Use of conformal therapy techniques increases the number of beams used in order to obtain better conformation of the treated volume to the planning target volume. As the number of beams increases, the number of monitor units (MU) for each beam decreases. In this work we have studied, the influence of low MU on dose and homogeneity. METHODS AND MATERIALS: To study the field symmetry and flatness, films were irradiated. The "dose" for each field was always 60 MU; but it was divided into different segment sizes: 2 segments of 30 MU, 3 segments of 20 MU, and so on up to 12 segments of 5 MU. After being developed, films were scanned and analyzed using a densitometer. The measurements were carried out for three X-ray energies: 6 MV, 10 MV, and 18 MV. RESULTS: Each measurement was repeated twice for each energy, and the results were equal. The means of the symmetry and flatness values obtained for each energy are lower than the commonly accepted limits. CONCLUSION: The dose delivered by adding small segments is equivalent to the dose delivered by a conventional segment with our Philips Linacs SL15 and SL20.

Phantoms, Imaging↗
PubMed2000

Conformal radiotherapy for paranasal sinus and nasal cavity tumors: three-dimensional treatment planning and preliminary results in 40 patients.

PURPOSE: To assess the possibility to deliver a high and homogeneous irradiation with respect to maximal tolerated dose to the visual pathways for paranasal sinus and nasal cavity tumors. METHODS AND MATERIALS: Forty patients with advanced stage malignant tumors were treated with postoperative (30) or primary (10 patients) conformal radiotherapy (CRT). Five patients were previously irradiated. Six to 15 individually shaped isocentric noncoplanar field arrangements, using a multileaf collimator were designed. Dose-volume histograms (DVH) for the planning target volumes (PTV) and the optic pathways were analyzed in 31 cases. RESULTS: Median and maximal delivered doses to the PTV were 60 (+/-3) and 66 (+/-4) Gy. Dose distributions for critical organs are detailed. Median follow-up was 19 months (3 to 48). Local, nodal, and metastatic recurrences occurred in 8, 2, and 7 cases, respectively. Major prognostic factor for local recurrences was central nervous system (CNS) involvement. One patient died of meningitis. Two patients developed cataract, and 1 patient ipsilateral blindness due to vascular glaucoma. CONCLUSION: CRT for locally advanced paranasal sinus and nasal cavity tumors enables the delivery of high homogeneous doses to the PTV with respect to critical organs, with a low toxicity and a high local control.

Adult↗
PubMed2000

Prospective evaluation of early lung toxicity following three-dimensional conformal radiation therapy in non-small-cell lung cancer: preliminary results.

PURPOSE: Radiation pneumonitis is the restricting complication following lung cancer irradiation. The correlation between dose-volume histograms (DVHs) and pneumonitis, with a clinical, radiological, and respiratory function evaluation was assessed. Special endpoint was the evaluation of respiratory function after three-dimensional conformal radiotherapy (3D-CRT). METHODS AND MATERIALS: Fifty-four patients with non metastatic non-small-cell lung cancer (NSCLC) were treated with a curative intent with 3D-CRT (66 Gy). Thirty-one patients were treated postoperatively (pneumonectomy in 9 patients) for residual tumor or massive nodal involvement (N2 or N3); 23 patients were treated with exclusive radiotherapy. Clinical evaluation, CT scan, and pulmonary functional tests were performed before and 6 weeks after irradiation. The DVHs were calculated applying lung density heterogeneity. RESULTS: Twenty patients had radiation pneumonitis. Irradiation significantly decreased total lung capacity. Volume of the PTV2 (more than 200 cm(3)) was a significant prognostic factor for lung complication. CONCLUSION: DVHs combined with initial pulmonary functional tests can predict pulmonary toxicity and could allow us to adjust volume that received total highest dose with acceptable toxicity.

Adenocarcinoma↗
PubMed2000

Impact of tissues heterogeneities on monitor units calculation and ICRU dose point: analysis of 30 cases of prostate cancer treated with 18-MV photons after three-dimensional planning.

PURPOSE: Analysis of dose specification of tissue heterogeneities. METHODS AND MATERIALS: Three-dimensional dose distribution analyses of 30 patients with localized prostate cancer were reviewed with and without tissue heterogeneity correction. The number of monitor units for each portal entrance (more than 300 different fields) was calculated and the impact of targeting and number of portal entrances was also integrated. RESULTS: The presence of gas in the rectum induces an overdosage of 0.6%, pubic bone induces an underdosage of -1.5%, and femoral heads are responsible for 6% underdosage. For the treatment as a whole, the underdosage is correlated with targeting techniques and weighting of each portal entrance (range, -0.5% to -3.2%). CONCLUSION: Dose calculation must take into account tissue heterogeneities and more precise guidelines for dose prescription are mandatory for further intercomparison.

Algorithms↗
PubMed2000

Dose escalation with 3D-CRT in prostate cancer: French study of dose escalation with conformal 3D radiotherapy in prostate cancer-preliminary results.

PURPOSE: To evaluate the feasibility of dose escalation in a multi-institutional study in prostate cancer patients. METHODS AND MATERIALS: Between October 1995 and October 1998, 164 patients with localized adenocarcinoma of the prostate were treated with 3-dimensional conformal radiotherapy at one of five French institutions. The dose of radiation was escalated from 66 to 80 Gy (ICRU point). The maximum dose to the rectal wall was limited to 75 Gy. RESULTS: Results were compared in two groups, one (group 1) receiving the standard dose (n = 46 patients; 66 to 70 Gy) and the other (group 2) receiving the escalated dose (n = 118 patients; 74 to 80 Gy). There was no difference in the characteristics of patients between the two groups. The mean follow-up time was 32 months in group 1 and 17.5 months in group 2. No statistical difference between the two groups was observed in the incidence of late gastrointestinal and urinary toxicities. The probability of achieving a posttreatment prostate-specific antigen nadir of </=1 ng/mL in the 120 patients who did not receive neoadjuvant androgen-deprivation therapy was significantly higher in the dose-escalation group and was directly related to the dose of radiation given. CONCLUSION: This multi-institutional study demonstrated the feasibility of escalating the dose of radiation to 80 Gy in prostate cancer patients.

Adenocarcinoma↗
PubMed2000

Primary cerebral lymphomas: unsolved issues regarding first-line treatment, follow-up, late neurological toxicity and treatment of relapses. The FNCLCC. French Fédération Nationale des Centres de Lutte contre le Cancer.

BACKGROUND: Primary cerebral non-Hodgkin's lymphomas (NHL) in immunocompetent patients (PCL) are located exclusively in the central nervous system, the eye, or meninges. Clinical management of these patients remains controversial. PATIENTS AND METHODS: Clinical characteristics of the patients and parameters influencing their outcome as of December 1998 were investigated and registered in a database of 226 patients treated in the French Federation of Cancer Centers between 1980 and 1995. RESULTS: Most PCL are diffuse large-cell NHL with a B phenotype. The incidence of PCL has been steadily increasing over the past 20 years in some but not all countries. The overall survival of primary cerebral lymphoma (PCL) patients in the published series, a median of 12-16 months and a five-year survival of 5%-20%, is poor. Several series have now reported long-term survivals of more than 10 years and PCL may therefore be a curable tumor in some patients. The optimal treatment of PCL is not known. Complete resection of the tumor does not improve outcome and multidisciplinary approaches combining chemotherapy and radiotherapy are now commonly used, although the superiority of combination over radiotherapy- or chemotherapy-alone has never been demonstrated in a phase III trial. The optimal chemotherapy regimen, the dose and even the usefulness of brain radiotherapy after chemotherapy are therefore still matters of debate. Recently, several authors have reported a relatively high incidence of late neurological sequelae after PCL treatment. CONCLUSIONS: The optimal treatment of PCL patients remains to be defined. Large cooperative international phase III trials are now required to define and improve the optimal treatment of PCL and reduce its sequelae.

Antineoplastic Combined Chemotherapy Protocols↗
PubMed2000

[Innovations in the treatment of medulloblastoma].

Prognosis of medulloblastoma remains serious with a disease-free survival rate of 70% at 5 years and severe sequelae in the majority of children. In order to improve this survival rate without unacceptable toxicity, various ways are currently under investigation. Among them, hyperfractionation and conformal therapy seem to be promising. Quality control of radiotherapy treatment could surely also play a major role on outcome.

Cerebellar Neoplasms↗