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At least 217 records · Page 12Linked to original sources
PubMed1996

Combined surgery and brachytherapy in the treatment of some cancers of the bladder (partial cystectomy and interstitial iridium-192).

Eighty-five bladder cancers were treated at the Urology Clinic of Nancy and the Centre Alexis Vautrin from 1975 to 1992 with short course preoperative radiation therapy (3 x 3.5 Gy), conservative surgery and brachytherapy by iridium-192. The tumours were classified according to the 1979 UICC pTNM classification. There were 27 pT1, 31 pT2 and 22 pT3, two pT4 and three pTx. The pT1-pT2 cases received only one brachytherapy (50 Gy at least) after the short course preoperative irradiation. The pT3 cases received only 30 Gy of brachytherapy and an external irradiation boost (generally 40 Gy to the node areas and 30 Gy to the tumour, but the dose varied during the time course). Surgery was often preceded by an endoscopic resection consisting of a tumoral resection or a partial cystectomy according to the localisation. The plastic vector tubes were put into place at the time of partial cystectomy. Until 1983 the radioactive wires were loaded into the vector tubes on the day following surgery, thereafter it was done one week later. The 85 patients were classified into two groups: 63 patients who were untreated previously and 22 patients who had received one or more endoscopic resections for recurrences. The median follow-up was 84 months. The local controls at 5 years were 78% in the first group versus 56% in the second group (p = 0.005) with an overall survival of 73 and 65%, respectively. The local control did not vary according to the differentiation (grade 1/2 vs. grade 3). The local control for pT1, pT2, pT3 was 85, 64 and 70% with a specific survival of 85, 76 and 72%, and an overall survival of 78, 66 and 66%. Among early complications, delay in healing of the bladder wall with subsequent vesico-cutaneous fistula depends mainly on the loading time of radioactive wires after surgery and is rare if the loading is delayed by one week. The late complications depend mostly on dosimetric factors. We found 24 grade 1, three grade 2, four grade 3 and one grade 4. The following factors are significant: the surface treated (> 14 cm2), a distance between the sources of more than 2 cm and, especially, activity of the wires of more than 2 mCi/cm (this factor was found in the five complications of grade 3 and 4), the other factors were not significant in univariate analyses.

Brachytherapy↗
PubMedDate not supplied

Iridium 192 implantation of squamous cell carcinomas of the oropharynx.

From 1970 to 1984, 127 patients with T1 or T2 carcinomas of the oropharynx were treated with external irradiation to the primary tumor and neck nodes to a dose of 45 Gy, followed by a further 30 Gy delivered by an iridium 192 implant to the primary tumor. Patients with clinically positive nodes had either further neck irradiation using electrons or a neck dissection. Crude 5-year disease-free survival was 66% for tonsillar carcinomas, 43% for soft palate, and 51% for base of tongue. Local control was 98%, 85%, and 76%, respectively. Regional control was 97% for N0 patients and 88% for N1-3. Soft tissue ulceration occurred in 17 patients; all healed spontaneously. The high rate of local control achieved in these patients while preserving function and minimizing xerostomia supports the use of this approach.

Adult↗
PubMed1992

Treatment of oral cancer by interstitial irradiation using iridium-192.

Sixty-seven patients with squamous cell carcinoma of the oral cavity were treated by implantation of radio-active iridium wire between 1977 and 1986. The results are presented in the hope of providing a comparison with those of primary surgical management. The crude 5-year survival rates were 61% for T1, 74% for T2, and 37% for T3 tumours. The major causes of death were uncontrolled tumour in the neck and intercurrent disease. Seven of 52 patients with T1 or T2 tumours (13%) developed local recurrence at the primary site; five were salvaged surgically, for an ultimate failure rate of 4%. The ultimate failure for a group of 15 T3 tumours was 47%. The only morbidity was a 31% incidence of soft tissue ulcers occurring during the first 18 months after treatment, none of which persisted. Elective external beam radiotherapy to the clinically negative neck significantly reduced the incidence of overt lymph node metastases.

Adult↗
PubMed1991

Iridium implant treatment without external radiotherapy for operable breast cancer: a pilot study.

A pilot study has been conducted to examine a new approach to the treatment of operable breast carcinoma. 27 patients with tumours measuring up to 4 cm in diameter have been treated by tumourectomy, axillary clearance and high dose iridium-192 implant (55 Gy) without any external beam radiotherapy. This enabled the entire local primary treatment of the breast carcinoma to be given in five days. The technique was compatible with adjuvant chemotherapy for those with involved axillary nodes. Local complications have been few and locoregional control has to date been satisfactory. With a relatively short median follow-up of 27 months, cosmesis was objectively rated as good or excellent in over 80% of cases and subjectively rated good/excellent in 96%. High dose brachytherapy now requires testing in a prospective clinical trial to determine whether it is as effective as standard breast conservation techniques for management of early breast cancer.

Adult↗
PubMed1985

Management of malignant airway obstruction: clinical and dosimetric considerations using an iridium-192 afterloading technique in conjunction with the neodymium-YAG laser.

Fourteen patients with malignant airway obstruction have had 21 placements of a flexible nylon catheter for afterloading Iridium-192 using the flexible fiberoptic bronchoscope. Prescribed therapy was completed in 13 patients (18 courses). All patients had prior full-dose external irradiation, and no effective surgical or chemotherapeutic options remained. While many have had a trial of neodymium-YAG (yttrium-aluminum-garnet) laser therapy alone, eight patients received laser treatment one to three weeks prior to planned brachytherapy to provide immediate relief of symptoms and/or facilitate access and safe catheter placement. Most patients (64%) had recurrent squamous cell lung cancer. A dose of 3000 cGy is currently specified to 5 mm and 10 mm in the bronchus and trachea, respectively. Nine of the 13 treated patients have had follow-up bronchoscopy at approximately three months post-treatment with improvement documented in seven and progression in two patients. One patient was clinically improved without follow-up bronchoscopy, and three patients have had insufficient follow-up. A single patient treated with laser and 6000 rad at 5 mm developed a bronchoesophageal fistula. No other complication has been observed. The technique is simple and safe with the use of laser therapy when needed and appears to offer effective palliation in most patients even when standard therapy is exhausted.

Airway Obstruction↗
PubMed1985

Pelvic lymphadenectomy combined with transperineal interstitial implantation of iridium-192 and external beam radiotherapy for locally advanced prostatic carcinoma: technical description.

Regardless of the treatment modality, control of locally advanced extracapsular prostatic cancer remains a therapeutic challenge. At the Mayo Clinic, we have recently developed a combined approach for surgically staged patients employing interstitial irradiation with 192 Iridium via a transperineal template. The Martinez Universal Perineal Interstitial Template (MUPIT-II) and moderate doses of external beam irradiation. The procedure consists of: 1) preoperative single dose external beam irradiation to decrease potential for tumor seeding or showering of malignant cells during MUPIT-II placement; 2) adequate surgical staging through a bilateral retroperitoneal lymphadenectomy; 3) transperineal interstitial implantation of the tumor and retropubic palpation of the needles to verify proper position; 4) intraoperative X rays are taken and used for documentation of needle position as well as for calculation and optimization of the implant dose distribution with the aid of a computerized system; 5) moderate doses of external beam irradiation postoperatively to the prostate with adequate margins. Our favorable preliminary results obtained in 18 patients treated with the above approach warrant the continuation of this trial. Details of this technique are presented.

Adenocarcinoma↗
PubMed1987

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

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.

Adult↗
PubMed1988

Salvage irradiation of oropharynx and mobile tongue about 192 iridium brachytherapy in Centre Alexis Vautrin.

Between 1972 and 1984, 123 patients were treated using 192 Iridium afterloading techniques for recurrence or new cancer of the tongue or oropharynx arising in previously irradiated tissues. The actuarial local control was 67% at 2 years and 59% at 5 years. Local control of the tumor was achieved in the majority of these patients, the actuarial survival was only 48% at 2 years and 24% at 5 years. Twenty-eight patients developed mucosal necrosis. We analyzed prognostic factors for survival, local control, and complication. We proposed a selection for this salvage therapy.

Brachytherapy↗
PubMed1988

Dosimetric calculations and measurements of gold plaque ophthalmic irradiators using iridium-192 and iodine-125 seeds.

The dosimetry of ophthalmic plaques designed to hold iridium-192 or iodine-125 seeds is investigated experimentally and by means of a computer model. A phantom for thermoluminescent dosimetry (TLD) which permits measurements to within 2 mm of the plaque surface is described. TLD data are compared with model calculations that take into account the active length of the seeds, anisotropy of dose distribution from single seeds, and scatter within the phantom. An isotropic point source calculational model is accurate for clinical calculations, particularly at depths greater than 5 mm. Relative central axis dose measurements for 125I in a gold plaque are also in agreement with the model. Comparisons of 192Ir, 125I and 60Co plaques are presented. The relative advantages of using these isotopes in eye plaques are discussed.

Brachytherapy↗
PubMed1988

Intracatheter hyperthermia and iridium-192 radiotherapy in the treatment of bile duct carcinoma.

We report a case of a patient with locally advanced bile duct carcinoma treated with 4500 cGy external beam radiotherapy, followed 3 weeks later by intracatheter 915 MHz microwave hyperthermia and radiotherapy delivered through a biliary U-tube placed at the time of surgery. Heating was to 43-45 degrees C for 1 hour followed immediately by intracatheter Iridium-192 seeds to deliver 5000 cGy over a 72 hour period. Prior to treatment, a thermal dosimetry study in phanton was conducted, using the same type of U-tube catheter tubing as in the patient. Orthogonal X rays of the patient's porta hepatis region were used to reconstruct the catheter geometry in the phantom. Proper insertion depth was determined thermographically to obtain maximum heating at the center of the tumor. The maximum SAR was 8.8 watts per kilogram per watt input. During the treatment, the average power applied was 30 W. Six months after therapy, the patient is asymptomatic. Although alkaline phosphatase, SGOT and SGPT have remained elevated, bilirubin has returned to normal and computerized tomographic scans and cholangiograms remain stable. A duodenal ulcer developed after therapy and is healing well with conservative medical management. This case demonstrates that hyperthermia applied through biliary drainage catheters is technically feasible and clinically tolerated. We believe the use of intracatheter hyperthermia in conjunction with external and/or intracatheter radiotherapy in selected patients with unresectable bile duct carcinomas warrants further study.

Alanine Transaminase↗
PubMed1989

Effect of dose rate on local control and complications in the reirradiation of head and neck tumors with interstitial iridium-192.

Interstitial Iridium-192 was used as the sole treatment for 23 previously irradiated patients with recurrent or second primary malignancy in the head and neck region. Doses used in initial external beam treatment ranged from 50.0 to 72.0 Gy, in daily fractions of 180 to 200 cGy. Retreatment with interstitial implant using the Quimby system delivered total doses between 38.5 and 60 Gy, with hourly dose rates of 30 to 66 cGy. Local control in the implanted volume was seen in 21 of 23 patients at 5 to 34 months post-implant (median 10 months). Dose rate (hourly dose delivered at 0.5 cm beyond the periphery of the implanted tumor volume) did not affect local control, but did have a significant impact on severe complications (soft tissue necrosis and fistulae; p = 0.26). No effect on either local control or complication rate was found for volume of implant, initial external beam radiation dose, time to recurrence, or anatomic site of treatment. These findings suggest that interstitial irradiation is effective treatment for head and neck cancers in previously irradiated sites. Dose rates as low as 32 cGy/hr provided adequate local control, with few long-term complications to date; doses above 42 cGy/hr may be associated with severe and even fatal complications.

Adult↗
PubMed1990

Interstitial iridium 192 for cutaneous carcinoma of the external nose.

Several implantation techniques useful for nasal skin carcinoma have been developed at the Henri Mondor Hospital in Créteil, France and are described in detail. Iridium 192 wires, 0.3 mm in diameter, are afterloaded into either supple plastic tubes or rigid needles implanted according to the rules of the Paris system. Dosimetry is performed by computer, based on either direct measurements of active lengths and spacing, orthogonal films or a tomogram oriented in the central plane of the implant. According to a recent review by the European Curietherapy Group of 468 implants, the optimal dose is 60 Gy. The overall failure rate was 2.6%. Indications for implantation and choice of technique, based on tumor size, site, and gross morphology are discussed.

Brachytherapy↗
PubMed1990

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

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.

Adult↗
PubMed1990

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

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.

Adult↗
PubMed1991

Twenty years experience of interstitial iridium brachytherapy in the management of soft tissue sarcomas.

From February 1968 to February 1988, 50 patients above 10 years of age with a soft tissue sarcoma were treated with interstitial brachytherapy, combined with a wide excision. After pathologic review, 48 were included in the final analysis. A pathological grading was made possible in 41, which showed a majority of high grades (2 + 3 = 86%). Patients presented mainly with small (less than 5 cm: 36) or mid-size lesions (greater than 5 cm: 12). The tumor was located in the limbs (32), trunk (9), and head and neck (7). Four patients had metastases at the time of treatment. Brachytherapy was part of the initial treatment in 22 cases, and of a salvage procedure after previous excision(s) combined or not with another form of treatment in 26. A uniform technique of iridium 192 wires after-loaded in plastic tubing was used. Sixty Gy median doses were delivered with brachytherapy alone (44) or combined with external beam (4). Sixteen patients also received an adjuvant chemotherapy. Follow up ranged from 16 months to 20 years (median 82 months). At the time of analysis, two patients (4%) only had failed in the irradiated volume, but the marginal failures rate (14:31%) was unexpectedly high. Seven of the patients who failed (43%) were salvaged by a second similar procedure. The 5-year survival was 62% in non-previously treated patients and 56.5% in previously treated ones (pNS). By multivariate analysis, only the tumor location appeared predictive of LF (p less than 0.01), which in turn was strongly correlated with the metastatic outcome (p less than 0.01). Necroses were observed in 17 cases (35%) and associated with a benign course in most of them. High dose brachytherapy combined with conservative surgery is highly effective in small and mid-size soft tissue sarcomas located in the extremities and head and neck, whereas in trunk and in recurrent tumors, the adjunction of large fields external radiotherapy and/or possibly polychemotherapy appears necessary.

Adolescent↗
PubMed1991

Split course interstitial brachytherapy with a source shift: the results of a new iridium implant technique versus single course implants for salvage irradiation of base of tongue cancers in 55 patients.

Between January 1973 and December 1984, 55 patients with prior irradiation of the oropharynx underwent salvage irradiation for recurrent (26 patients) or second cancers (29 patients) of the base of tongue. The initial irradiation had delivered from 45 to 80 Gy to the base of tongue. One of two techniques of Iridium implantation was used for salvage. Single course implants, delivering 60 Gy, were used until June 1981 in a total of 31 patients. After June 1981, split course implants with a source shift were used in 24 patients in the hope of decreasing treatment complications. The first and second course of the split course implants delivered 35 and 30 Gy, respectively, at a 1-month interval. The active lines of the second implant were placed parallel to and between the position of the lines of the first implant. This shift in the source position resulted in a more uniform dose within the treated volume with a 60% reduction in the high dose sleeves. The overall 3-year survival was 19% (28% T less than or equal to 3 cm). The overall local failure rate was 45.5% (25/55). The difference between the local failure rate after single course implants (52%) and after split course implants (37.5%) was not statistically significative. The response observed after the first course of a split course implant proved to be a reliable indication of the probability of achieving local control after a full course of treatment: 2/14 failures (14%) if the response was greater than or equal to 75% versus 7/10 (70%) if the response was less than 75% (p less than 0.01). The only complication noted in the 40 patients achieving immediate local control after either implant technique was mucosal necrosis. The introduction of split course implants was followed by a two and a half fold decrease in the incidence of necrosis: 43% (9/21) in the single course group and 16% (3/19) in the split course group (p = 0.05). Interstitial brachytherapy offers an effective and reasonable option for salvage therapy in patients with recurrent and second cancers occurring in the base of tongue even when the tumor arises in a zone that has previously received high dose irradiation. The use of split course implants with a shift in the position of the active lines at the time of the second implant significantly decreases the risk of radionecrosis.

Aged↗
PubMed1992

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

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.

Adenocarcinoma↗
PubMed1992

Iridium-192 interstitial therapy for squamous cell carcinoma of the penis.

From February 1971 through February 1989, 51 patients with biopsy proven epidermoid carcinoma of the penis were treated with interstitial therapy (Iridium 192). The breakdown according to the stage was T1s = 3, T1 = 14, T2 = 28, T3 = 6, N0 = 43, N1 = 7, N2 = 1. The dose ranged from 50 to 65 Gy (mean: 60 Gy). Patients without clinical nodal involvement received no treatment to the nodes. Stage N1 and N2 patients had surgery and external irradiation to the inguinal and iliac nodes. Six of fifty-one (12%) patients developed nodal and/or metastatic disease following therapy. Five of six presented initially with clinical nodal involvement. Seven of fifty-one (14%) developed local recurrence only, requiring surgery (four partial penectomies, three total penectomies). Six of these seven patients are alive and free of disease with a mean follow-up of 5.5 years. Nine of thirty eight (23%) patients with local control developed local necrosis. The treatment consisted of local excision (one patient), partial amputation (six patients) or total amputation (two patients). Partial urethral stenosis was noted in 17/38 (45%) of the patients. Foreskin sclerosis occurred in 3/38 (8%) uncircumcised patients. Interstitial irradiation for penile carcinoma provided effective local control rates, especially for T1-T2 patients (91%). Local failures could be treated successfully with surgery. Complications could be treated conservatively in most patients. Local control with penile conservation was achieved in 67% of all patients and 75% of patients with T1-T2 disease.

Adult↗