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International Journal of Radiation Oncology Biology Physics | 1987

Salvage irradiation of oropharyngeal cancers using iridium 192 wire implants: 5-Year results of 70 cases

J.J. Mazeron; Denis Langlois; Daniel Glaubiger; Judith Huart; Michel Martin; Michel Raynal; E. Calitchi; G. Ganem; Marl Faraldi; Franck Feuilhade; B. Brun; Lorraine Marin; Jean-Paul Le Bourgeois; François Baillet; Bernard Pierquin

Between May 1971 and November 1980, 70 patients with recurrent or new oropharyngeal cancers arising in previously irradiated tissues were treated using iridium 192 afterloading techniques. The actuarial local control was 72% at 2 years and 69% at 5 years. Although local control of the tumor was achieved in the majority of these patients, only 10 patients remained alive at 5 years (14%). Patients with lesions of the faucial arch and posterior pharyngeal wall had the best results; local control was achieved in 100% of these patients. Patients with lesions of the base of tongue and of the glosso-tonsillar sulcus had poorer results; local control was achieved in 61%. Because these results compare favorably with the results of previously published series, we recommend re-irradiation with brachytherapy for recurrent or new malignancies arising in a previously irradiated oropharynx. When the lesion is located in the faucial arch, brachytherapy is the treatment of choice. When the lesion is located in the base of tongue, brachytherapy is a reasonable option.


Radiotherapy and Oncology | 1991

Effect of dose rate on local control and complications in definitive irradiation of T1-2 squamous cell carcinomas of mobile tongue and floor of mouth with interstitial iridium-192.

J.J. Mazeron; Jean-Marc Simon; C. Le Pechoux; Juanita Crook; Laval Grimard; Pascal Piedbois; J.P. Le Bourgeois; Bernard Pierquin

From 1971 to 1988, 134 T1 and 145 T2 biopsy-proven squamous cell carcinomas of mobile tongue and floor of mouth were definitively managed by iridium-192. Implantations were performed using either guide gutters or afterloading plastic catheters. The prescribed dose at the reference isodose (85% of the basal dose rate, Paris system) was 60-70 Gy. Total dose was not adjusted to dose rate or tumor volume. Results of the 279 implants have been analysed to look for a possible influence of dose rate on local control and necrosis. Follow-up patients free of local recurrence is 1-180 months with average of 51 months. The 279 tumors were divided in four groups according to dose and dose rate: greater than or equal to 62.5 Gy and greater than or equal to 0.5 Gy/h (n = 130), greater than or equal to 62.5 Gy and less than 0.5 Gy/h (n = 36), less than 62.5 Gy and greater than or equal to 0.5 Gy/h (n = 81), less than 62.5 Gy and less than 0.5 Gy/h (n = 32). The four groups were comparable according to age, sex, tumor diameter and macroscopic aspect. At 5 years, the estimated local control (Kaplan Meier) was 93, 87, 79 and 52%, respectively (dose adjusted to dose rate: p less than 0.001, dose rate adjusted to dose: p less than 0.01, Log-rank); the necrosis rate was 44, 24, 37 and 5%, respectively (dose adjusted to dose rate: p = 0.08, dose rate adjusted to dose: p less than 0.01).(ABSTRACT TRUNCATED AT 250 WORDS)


International Journal of Radiation Oncology Biology Physics | 1988

Combined external irradiation and interstitial implantation for T1 and T2 epidermoid carcinomas of base of tongue: The creteil experience (1971–1981)

Juanita Crook; J.J. Mazeron; G. Marinello; Michel Martin; Michel Raynal; E. Calitchi; Marc Faraldi; G. Ganem; Jean-Paul Le Bourgeois; Bernard Pierquin

Forty-eight patients with T1 or T2 epidermoid carcinomas of the base of tongue were treated at the Henri Mondor Hospital between 1971 and 1981. Forty-one patients received moderate dose 60Co external beam irradiation (mean: 48.6 Gy) to the primary tumor and regional nodes, followed by an interstitial iridium 192 implant to the primary tumor (mean: 32 Gy). This completed the treatment for the 30 node negative patients, but those with clinically positive nodes were managed by either an additional electron beam boost to the involved nodes or a neck dissection. Seven tumors were treated exclusively by implantation to the base of tongue (mean: 63 Gy). Five-year crude disease-free survival is 50% with 35% of patients dying of recurrent disease. Definitive local control for T1 lesions is 85% (11/13) and for T2 is 71% (25/35). A dose response effect was observed with local control of 79% (26/33) obtained with a combined dose greater than or equal to 75 Gy, but only 50% (4/8) for less than or equal to 70 Gy. For N0 patients definitive regional control is 97% and for N1-3 is 89%. Minor or moderate soft tissue ulceration was observed in 12 patients, including 3 cases that progressed to osteonecrosis. None required surgical intervention. No correlation exists between necrosis and tumor size or total dose.


International Journal of Radiation Oncology Biology Physics | 1990

Iridium 192 implantation of T1 and T2 carcinomas of the mobile tongue

J.J. Mazeron; Juanita Crook; V. Benck; G. Marinello; M. Martin; Michel Raynal; Elias Haddad; Roger Peynegre; J.P. Le Bourgeois; W. Walop; Bernard Pierquin

Between 1970 and 1986, 166 patients with T1 or T2 epidermoid carcinomas of the mobile tongue were treated by iridium 192 implantation (70 T1N0, 83 T2N0, 13 T1-2 N1-3). Five-year actuarial survival was 52% for T1N0, 44% for T2aN0, and 8% for or T1-2 N1-3. Cause specific survivals were 90%, 71%, and 46%, respectively. Local control was 87% for both T1N0 and T2N0, and 69% for T1-2 N1-3. Seven of 23 failures were salvaged by surgery, increasing local control to 96% for T1 and 90% for T2. Thirty-six patients developed a minor or moderate necrosis (16% T1, 28% T2). Half of these involved bone but only five required surgical intervention. Both local control (LC) and necrosis (nec) increased with increasing dose but improvement beyond 65 Gy is minimal (less than or equal to 60 Gy: LC = 78% nec = 13%; 65 Gy: LC = 90% nec = 29%; greater than or equal to 70 Gy: LC = 94% nec = 23%). For N0 patients, neck management consisted of surveillance (n = 78), elective neck dissection followed with external irradiation for pathologically positive nodes (n = 72), or irradiation (n = 3). Clinically positive nodes (13 patients) were managed by either neck dissection followed by external irradiation if pathologically positive (n = 10) or irradiation alone (n = 3). Regional control was 79% for N0 patients, improving to 88% after surgical salvage, and was 9/13 for N1-3 patients. We recommend that T1 and T2 carcinomas of the mobile tongue be treated by iridium 192 implantation to deliver 65 Gy. Mandibular necrosis should be reduced by using an intra-oral lead-lined dental mold.


Radiotherapy and Oncology | 1986

Conservative treatment of breast cancer in Europe: Report of the Group Européen de Curiethérapie

Bernard Pierquin; J.J. Mazeron; Daniel Glaubiger

These two meetings organised successively to discuss the conservative methods of treatment of breast cancer, made it possible to gather data on a substantial number of patients from an important number of European centers. It is encouraging to note that there is a general consensus among the various European centers concerning the basic principles of treatment and that long years of experience have led to the use of well defined technical protocols which are relatively similar from one center to another. Since serious complications have now become exceptional, we foresee that the conservative treatment of breast cancer will continue to evolve on a technical level as the indications for this approach continue to develop within the overall plan of patient care with the assurance that optimum results may be maintained. However, we must point out that the lack of a unified system of reporting irradiation doses in volumes corresponding to the possible and/or real extension of the tumor remains an obstacle in developing a truly unified attitude in the application of these techniques. Each center defines the radiation dose given by wide field techniques and the dose given by cone-down (boost) techniques in a relatively arbitrary way without true anatomic correlations. These correlations must be found and defined, so that a specified dose has a universal meaning. The role of the surgeon in the successful application of breast conserving techniques is far from negligible. Now that our colleagues who wield the scalpel have begun to gain confidence in the curative powers of irradiation, we may hope that a close collaboration between radiotherapist and surgeon will lead to the application of conservative techniques under optimal conditions in the breast, with the development of minimal tumorectomy and minimal curative cone-down dose; and in the axilla, with the development of axillary dissection limited to the lower border of the pectoralis minor and followed by radiation therapy only if more than two nodes show tumor involvement. However, it is important to point out that while it is possible to use radiation therapy alone to treat breast cancer and conserve the breast at all stages of the development of the disease, it is not possible to use conservative surgical techniques alone as a substitute for adequate irradiation. The development of protocols which routinely apply breast conserving methods in synonymous with the development and routine use of the best radiation therapy techniques. This article presents two separate and complementary studies of two different sets of data presented at two successive meetings.(ABSTRACT TRUNCATED AT 400 WORDS)


International Journal of Radiation Oncology Biology Physics | 1990

Prognostic factors of local outcome for T1, T2 carcinomas of oral tongue treated by iridium 192 implantation

J.J. Mazeron; Juanita Crook; G. Marinello; W. Walop; Bernard Pierquin

The results of Iridium 192 implantation for 121 node negative T1 or T2 squamous carcinomas of mobile tongue were reviewed to look for predictors of local control and necrosis. Age, sex, total dose, dose rate, linear activity, and intersource spacing were examined. Minimum follow-up was 2 years but no patient with local recurrence or necrosis was excluded. There were 57 T1N0 tumors, 45 T2aN0 (2.1-3.0 cm), and 19 T2bN0 (3.1-4.0 cm). Local failures occurred in 14% of T1, 11% of T2a, and 26% of T2b. Univariate analysis showed that local control increased with increasing dose (55-60 Gy: 73%; 65-75 Gy: 92%, p = 0.005), whereas multivariate analysis revealed both sex and total dose to be significant. Radiation necrosis occurred in 17% of T1, 29% of T2a, and 47% of T2b (p = 0.034). Half were limited to soft tissue and the majority healed with conservative management. Univariate analysis showed that necrosis increased with increasing dose (55-60 Gy: 16%; 65-75 Gy: 33%, p = 0.037), as well as increasing dose rate, linear activity, and intersource spacing. With multivariate analysis only stage, dose rate, and spacing remained predictive of necrosis. Total dose was not adjusted for dose rate or tumor volume. This analysis suggests that within the therapeutic range of low dose rate brachytherapy, correction of total dose according to dose rate is unnecessary. We recommend 65 Gy. Lower dose rate (0.4-0.5 Gy/hr) and closer intersource spacing (12-14 mm) should be aimed for to minimize necrosis.


Radiotherapy and Oncology | 1990

Comparison of curietherapy versus external irradiation combined with curietherapy in Stage II squamous cell carcinomas of the mobile tongue

V. Benk; J.J. Mazeron; Laval Grimard; Juanita Crook; Elias Haddad; Pascal Piedbois; E. Calitchi; Michel Raynal; M. Martin; J.P. Le Bourgeois; Bernard Pierquin

One hundred and ten patients with Stage II epidermoid carcinomas of the mobile tongue were treated by interstitial irradiation (Group I: 85 patients) or external irradiation to the primary and the regional lymphatics followed by an interstitial boost (Group II: 25 patients). The neck was managed by either an elective neck dissection (43 patients) completed by external irradiation in 13 patients with pathological specimen or close follow-up (40 patients) with therapeutic neck dissection for relapses (7 patients) in Group I. Primary local control was 88% in Group I and 36% in Group II. Regional control was 91% in Group I and 5/6 in Group II for patients whose primary tumor was controlled. Five-year absolute disease-free survival (DFS) was 42% in Group I and 24% in Group II, but there was an imbalance in the distribution of larger tumors favoring Group I. There were 30 radiation-induced complications and four patients required corrective surgery. This retrospective analysis showed better results in patients whose primary was treated by interstitial irradiation alone which has the extra advantage of preserving salivary function.


Radiotherapy and Oncology | 2010

Patterns of care for brachytherapy in Europe: Updated results

Ferran Guedea; Jack Venselaar; Peter Hoskin; Taran Paulsen Hellebust; D. Peiffert; Bradley Londres; Montse Ventura; J.J. Mazeron; Erik Van Limbergen; Richard Pötter; György Kovács

OBJECTIVEnThis descriptive survey evaluated brachytherapy (BT) practices and resources in the European area. This was a follow-up study to the original patterns of care for brachytherapy in Europe (PCBE).nnnMATERIALS AND METHODSnA total of 1121 radiotherapy (RT) centres from 41 countries were asked to complete an online questionnaire on BT practices and resources. Countries with fewer than 50% of centres responding were excluded. Participating countries were divided into three groups based on gross domestic product (GDP); group I contained the countries with the highest GDP.nnnRESULTSnThe response rate was 56% (633/1121 centres) with 30/41 countries (73%) meeting the inclusion criteria. Sixty percent of reporting centres provided brachytherapy. Responding centres treated an average of 138 (±10, 1 SD) patients with BT; in group I, the mean was 110/centre, an increase of 18% from 2002. CT-dosimetry increased to 61% of centres vs. 33% in 2002. HDR (high-dose rate) BT was the most commonly reported technique (65% of centres). Most BT interventions were for gynaecological tumors (59% of all cases), followed by prostate (17%), breast (9%), lung/bronchus (3%), and esophagus tumors(2%).nnnCONCLUSIONnGynaecological BT remains the most common application, although both prostate and breast BT have increased. CT-based dosimetry has become increasingly common since 2002. The use of HDR and PDR (pulsed-dose rate) techniques has increased markedly, while both LDR and MDR (medium-dose rate) have declined.


International Journal of Radiation Oncology Biology Physics | 1990

Iridium-192 curietherapy for T1 and T2 epidermoid carcinomas of the floor of mouth

J.J. Mazeron; Laval Grimard; Michel Raynal; Elias Haddad; Pascal Piedbois; M. Martin; G. Marinello; Rama C. Nair; J.P. Le Bourgeois; Bernard Pierquin

From 1970 to 1986, 117 patients with T1 (47) or T2 (70) epidermoid carcinomas of the floor of the mouth (SCC) were treated by iridium-192 implantation (192 Ir). The dose was prescribed according to the Paris System and varied over those years. Follow-up information was available on 116 patients. There were 46 T1N0, 47 T2N0, and 23 T2N1-3. Neck management varied for the 93 N0 patients consisting of surveillance (24 T1, 17 T2) or elective neck dissection (22 T1:all pN-, 30 T2: 20 pN-, 10 pN+). Cause specific survival rates were 94% for T1N0, 61.5% for T2N0, and 28% for T2N1-3 at 5 years. Primary local control was 93.5%, 74.5%, and 65%, respectively, and 98%, 79%, and 65% after salvage. Patients with gingival extension or a tumor size over 3 cm (T2b) had a local control of 50% (9/18) and 58% (15/26), respectively. Nodal control was 93.5% for Stage I, 85% for Stage II, and 48% for T2N1-3 patients. There was no difference in nodal control with regard to treatment policy for Stage I-II patients. There were few complications including three deaths: two from surgery and one from 192 Ir. Nodal status, tumor size defined as T1, T2a (less than or equal to 3 cm), T2b (greater than 3 cm), and gingival extension were the only independent prognostic factors. The management of T1N0 and T2N0 SCC by 192 Ir to a dose of 65 or 70 Gy, using the Paris System, is recommended for lesions 3 cm or less and without gingival extension.


International Journal of Radiation Oncology Biology Physics | 1992

Interstitial iridium-192 for bladder cancer (A multicentric survey: 205 patients)

Raymond Rozan; Eliane Albuisson; Denise Donnarieix; Bernard Giraud; J.J. Mazeron; J.-Pierre Gerard; Monique Pernot; A. Gerbaulet; François Baillet; Jacques Douchez; Tan D. Nguyen

Interstitial irradiation is a technique currently used in the treatment of bladder cancer. We report the data on 205 patients (177 men and 28 women) treated in eight French centers. The patients had received the following treatment: a short course of pre-operative pelvic irradiation, followed by surgery consisting of partial cystectomy or tumor resection, and implantation of plastic tubes filled with inactive lead wires, which were replaced by iridium 192 wires. The tumor characteristics were: transitional cell carcinoma, 88.8%; mean size of the tumor, 29 mm; pathological stages: pTis, 1; pT1, 98; pT2, 66; pT3a, 26; pT3b, 9; pT4, 1; unknown, 4 respectively; surgical lymph node status: N+, 3; N-, 118; no node dissection, 84. The mean follow-up was 51 months. Intravesical failures were seen in 35 patients (17.0%), 25 (71.4%) of them without metastases or regional recurrences. Twenty-one patients (10.2%) presented distant metastases, 2/3 of them suffered no bladder relapse. The 5-year survival, calculated according to the Kaplan-Meier method (all causes of death taken together) was 77.4% for the T1, 62.9% for the T2, and 46.8% for the T3. Fifty-three patients had immediate side-effects and three died from surgical complications. Twenty-nine patients had delayed bladder side-effects (haematuria, fistula, chronic cystitis). Six patients presented an ureteral stenosis. Of the disease-free survivors, 96.1% retained the bladder function. Three factors were significantly predictive of delayed side-effects: partial cystectomy, pre-operative radiotherapy total dose, and linear activity of the wires (p < 0.01). Comparing our results to different authors series interstitial irradiation is likely to provide a high local and general control of the disease and good quality of life in patients with selected tumors.

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Juanita Crook

University of British Columbia

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G. Ganem

Institut Gustave Roussy

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M. Martin

University of Washington

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Erik Van Limbergen

Katholieke Universiteit Leuven

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