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PubMed1988

Conservative treatment of bladder carcinoma by partial cystectomy and interstitial iridium 192.

From 1971 to 1984, 85 patients with bladder carcinoma were treated conservatively at the Henri Mondor Hospital by a combination of short course of pre-operative external pelvic irradiation, iliac node dissection, partial cystectomy, and iridium 192 implantation. There were 79 transitional cell carcinomas (G1: 12, G2: 25, G3: 36, Gx: 6) and 6 squamous cell carcinomas. By clinical stage, based on endoscopic resection, there were 43 T1, 30 T2, 5 T3, and 7 Tx. After partial cystectomy the pathologic stage distribution was: 41 pT1, 31 pT2, and 13 pT3. Crude disease-free survival at 5 years is 72% for T1 tumors and 55% for T2, but overall only 16% of patients died of bladder carcinoma. Local failures were seen in 11.5% of T1 and 0% of T2 tumors, and second bladder tumors developed at a distance from the treated site in 11.5% of T1 and 7% of T2. There is a non significant trend for intravesical recurrences (both local failures and second tumors) to occur more frequently for G1 tumors (25%) than for G2 (16%) or G3 (7%). At 5 years 95% of disease-free survivors have a functioning bladder. Regional or distant metastases occurred in 54% of patients with pT3 tumors and 10% of those with pT1 or pT2; within each stage there was no apparent influence of grade on metastatic risk. The four patients with histologically positive iliac nodes received additional post-operative external pelvic irradiation; three died of metastases and one is disease free at 10 years. No abdominal scar recurrences were seen. Late complications occurred in 6% of the population. For T1 tumors we suggest modification of the described protocol, eliminating the pre-operative irradiation and the lymph node dissection. If there is no doubt as to the pathologic stage after complete endoscopic resection, iridium 192 implantation delivering a dose of 60 Gy, without partial cystectomy, may be sufficient management. By contrast, for T2 tumors, all elements of the protocol seem important to obtain optimal results.

Adult↗
PubMed1988

Treatment of bladder cancer with interstitial iridium-192 implantation and external beam irradiation.

Although interstitial implantation of invasive carcinoma of the bladder has been shown to be an effective treatment in Europe, there has been little experience with this method in the U.S. During the past 6 years, 14 patients at the Hospital of the University of Pennsylvania with single bladder tumors less than 5 cm and no evidence of carcinoma in situ on random bladder biopsies have been treated by a combination of external beam radiation and iridium wire implant. The iridium wire is inserted by an afterloading technique following tumor exposure via suprapubic cystotomy. Following delivery of the prescribed dose, the sources are removed percutaneously. Three patients with recurrent or high grade T1 lesions and 11 patients with T2-T3A lesions have been treated. With a median follow-up of 22 months (range 17 to 65 months), 9 patients are currently NED, 4 patients have died of disease, and 1 patient has died of intercurrent disease. There have been two isolated bladder recurrences, both non-invasive, one having been treated with cystectomy and one being treated locally. In addition, one patient developed regional failure, two developed distant metastases only, and one developed local recurrence following distant failure. The 2-year actuarial local control rate is 84%, with an overall 2-year actuarial survival of 66%. Complications have been minimal. Bladder implantation by this method is technically simple and produces excellent local control with acceptable morbidity.

Adult↗
PubMed1990

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

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.

Adult↗
PubMed1993

Influence of dose-rate and dose per fraction on clinical outcome of breast cancer treated by external beam irradiation plus iridium-192 implants: analysis of 289 cases.

PURPOSE: To study the influence of Iridium 192 implant dose-rate and dose per fraction of external irradiation on clinical outcome, the results in 289 patients with early breast cancer were analyzed retrospectively. METHODS AND MATERIALS: From 1980 to 1990, 118 T1 and 171 T2 lesions of breast were treated definitively by radiotherapy, following conservative surgery. External irradiation dose of 45 Gy was delivered either with 2.5 Gy or 1.8 Gy per fraction to the entire target volume, plus boost to the primary tumor. Boost dose of 15 to 30 Gy was given to the primary tumor either with iridium-192 implants or electrons. The implant dose-rate varied between 20 cGy/hr to 160 cGy/hr. RESULTS: The minimum follow-up was of 12 months and maximum of 11 years (median: 56 months). Out of 273 tumors boosted with implants, the 270 patients were divided into five groups according to dose-rate as, groups 1 (20-29 cGy/hr, n = 17), group 2 (30-49 cGy/hr, n = 144), group 3 (50-69 cGy/hr, n = 69), group 4 (70-99 cGy/hr, n = 27) and group 5 (100-160 cGy/hr, n = 13). The local failure rate was significantly increased in the group of patients treated with implant dose-rate < 30 cGy/hr (p < 0.05). While the incidence of late normal tissue complications and poor cosmetic outcome was significantly higher in the group of patients treated with implant dose-rate > 100 cGy/hr (p < 0.05). CONCLUSION: The present analysis indicate that the implant dose-rate should be maintained between 30-70 cGy/hr to maximize local control and reduce the late normal tissue injury. Also the increase in dose per fraction of external irradiation while not influencing local control rate was crucial for incidence of late complications and cosmetic outcome.

Adult↗
PubMed1994

Improved local control and survival for surgically staged patients with locally advanced prostate cancer treated with up-front low dose rate iridium-192 prostate implantation and external beam irradiation.

PURPOSE: In an effort to improve upon the historically poor local control and survival rates for locally advanced prostate carcinoma, a prospective multidisciplinary clinical trial was initiated using low dose rate Iridium-192 prostate implantation and external beam irradiation. METHODS AND MATERIALS: Between January 1983 and September 1989, 57 patients with newly diagnosed bulky prostatic carcinoma (5 Stage B2, 52 Stage C) were treated at the Mayo Clinic (34 patients) and William Beaumont Hospital (23 patients) with (a) 5 Gy delivered preoperatively in one fraction, (b) pelvic lymphadenectomy with interstitial implantation of the prostate using Iridium-192 seeds via a perineal template to 30-35 Gy, and (c) 30.6 Gy external irradiation to prostate only in 17 fractions. RESULTS: After lymphadenectomy, 30/57 (53%) patients had pathologically confirmed positive lymph nodes or "D1" disease. Thirty-four patients (60%) had Gleason scores > or = 7. Mean age at diagnosis was 63.3 years. Median overall follow-up was 72 months. The 5-year actuarial survival rate was 85% and disease-free survival was 63%. The 5-year survival for patients with negative nodes was 93% and with positive nodes was 79%. The corresponding survival for patients with Gleason scores < or = 6 was 96% and > or = 7 was 78%. Multivariate analysis demonstrated that of all covariates considered, only Gleason score had prognostic significance for disease-free survival (p < 0.05) and no covariates were statistically significant for overall survival. Thirty-nine of the 57 patients had a prostatic re-biopsy performed at 18 months. Pathologically confirmed local control was ultimately achieved in 31/39 (79.5%). There was no difference in survival in patients with positive re-biopsies vs. those with negative results. The 5-year actuarial rate of clinical local control was 94%. Three patients clinically failed locally and 21 demonstrated distant progression. The median time to progression was 34 months. Nineteen percent received some form of hormonal manipulation at the time of their treatment course and an additional 42% were treated with hormones during their follow-up period, primarily after distant failure. The grade 4 rectal ulceration rate decreased to 4.5% with modification of the brachytherapy technique. Three patients experienced grade 4 urinary incontinence and three patients experienced grades 3 or 4 chronic perineal pain. CONCLUSION: These results indicate that bulky prostate carcinoma can be successfully controlled locally by this novel and aggressive approach with moderate toxicity and improved survival.

Adenocarcinoma↗
PubMed1994

Iridium-192 interstitial implant and external beam radiation therapy in the management of squamous cell carcinomas of the tonsil and soft palate.

PURPOSE: To evaluate the results, techniques, indications and complications of interstitial brachytherapy in the management of squamous cell carcinomas of the tonsil and soft palate, we reviewed the Stanford University Medical School experience with this modality. METHODS AND MATERIALS: Between May 1975 and January 1990, 37 patients with squamous cell carcinomas of the Tonsillo-Palatine region were treated with a combination of external beam irradiation and a removable Iridium-192 interstitial implant. The mean age of these patients was 56. Twenty-two were males and 15 were females. The stage distribution included four patients with Stage I, 5 with Stage II, 10 with Stage III, and 18 with Stage IV cancers. Thirty-two percent (12/37) of these patients had T3 or T4 lesions. Forty-nine percent (18/37) had stage N2 or N3 cervical lymphadenopathy. All 37 patients received initial external beam irradiation to the primary, bilateral necks, and supraclavicular region (mean dose: 5400 cGy, range 4000-6600). Eighteen patients (49%) also received neck dissections. All 37 patients received an interstitial Irridium-192 implant using a combination intraoral swage and external looping technique. The mean dose was 2700 cGy (range 2000-4000 cGy) to an average volume of 24 cc (range 5-81). RESULTS: Local control was obtained in 95% (35/37) of the patients. Eighty-seven percent (32/37) of the patients have remained disease-free in the neck. Nine patients have developed second primary lesions, and one developed pulmonary metastasis. Fifteen patients have died (6 succumbed to their cancers, 6 to second primaries, 2 to intercurrent disease, 1 from an unknown cause). The actuarial freedom from relapse is 75%, and overall survival is 64% at 5 years, with a mean follow up of 43 months (range 5-110). Complications were limited to one case of osteoradionecrosis of the mandible and one tonsillar ulcer. Functional and esthetic integrity was preserved in most of these patients. CONCLUSION: Iridium-192 interstitial implant boost combined with external beam radiation therapy is a safe and effective therapy in the management of locally advanced carcinomas of the tonsil and soft palate.

Adult↗
PubMed1987

Palliation of obstructive oesophageal and cardial carcinomas with laser and endoluminal iridium radiation.

The combination of laser with endoluminal 192-iridium radiation for the palliation of malignancies of the oesophagus and the cardia has been introduced to overcome the short-lived effect of laser treatment alone. Concluding from early experience, this method seems to prolong the effect of laser treatment alone, with a low risk of complications. However the initial optimistic results, claiming a permanent relief of dysphagia in 80% of the patients, cannot be reproduced under prospective conditions. The combination of laser and 192-iridium radiation with other palliative methods, such as external radiation and/or chemotherapy is feasible and remains to be studied in a comparative way.

Brachytherapy↗
PubMed1989

Design and dose distribution for rectal applicators for the high dose rate remote afterloading iridium-192 brachytherapy system.

A Remote High Dose Rate (HDR) Brachytherapy Iridium-192 System for outpatient brachytherapy procedures necessitates a variety of applicators in order to accomplish the optimal desired treatment for the patient's tumor involved anatomy. The Nucletron Corporation that manufactures the microselection HDR Iridium-192 treatment unit provided us with their standard applicators; however, a rectal applicator system was not available at the time of purchase. In order to provide this treatment to the patient, the physicians and the physicists designed a custom set of rectal applicators that would meet the current and immediate needs of our patients. A description of the clinical rationale and physical aspects of the rectal applicator system, including design and radiation dosimetry will be presented.

Ambulatory Care↗
PubMed1996

Inadequacy of iridium implant as sole radiation treatment for operable breast cancer.

In order to avoid a prolonged course of external irradiation as part of breast conservation therapy, 27 patients received an iridium implant to the primary tumour bed as sole radiation treatment. Surgery was standardised comprising tumourectomy and axillary clearance. Using a rigid implant afterloading with iridium192 wires, 55 Gy was delivered on a continuous basis over 5 days. After 6 years median follow-up, relapse of cancer within the treated breast has occurred in 10 of the 27 patients (37%). Compared with historical controls treated by similar surgery and iridium192 implant (20 Gy) with external radiotherapy (46 Gy), there was a significantly increased breast relapse rate in those treated by iridium implant alone. However, the incidence of distant metastases and overall survival was similar. Thus, a continuous iridium192 implant delivering 55 Gy in 5 days is not an effective means of achieving local control in patients with operable breast cancer.

Brachytherapy↗
PubMed2004

Over-pulsing degrades activated iridium oxide films used for intracortical neural stimulation.

Microelectrodes using activated iridium oxide (AIROF) charge-injection coatings have been pulsed in cat cortex at levels from near-threshold for neural excitation to the reported in vitro electrochemical charge-injection limits of AIROF. The microelectrodes were subjected to continuous biphasic current pulsing, using an 0.4V (versus Ag|AgCl) anodic bias with equal cathodal and anodal pulse widths, for periods up to 7h at a frequency of either 50Hz or 100Hz. At charge densities of 3mC/cm(2), histology revealed iridium-containing deposits in tissue adjacent to the charge-injection sites and scanning electron microscopy of explanted electrodes revealed a thickened and poorly adherent AIROF coating. Microelectrodes pulsed at 2mC/cm(2) or less remained intact, with no histologic evidence of non-biologic deposits in the tissue. AIROF microelectrodes challenged in vitro under the same pulsing conditions responded similarly, with electrodes pulsed at 3mC/cm(2) showing evidence of AIROF delamination after only 100s of pulsing at 100Hz (10,000 pulses total), while electrodes pulsed at 2mC/cm(2) for 7h at 50Hz (1.3 x 10(6) pulses total) showed no evidence of damage. In vitro electrochemical potential transient measurements in buffered physiologic saline indicate that polarizing the AIROF beyond the potential window for electrolysis of water (-0.6 to 0.8V versus Ag|AgCl) results in the observed degradation.

Animals↗
PubMedDate not supplied

Treatment of malignant biliary obstruction by endoscopic implantation of iridium 192 using a new double lumen endoprosthesis.

Iridium 192 seeds contained in a ribbon were preloaded into a new double lumen 11 Fr endoprosthesis which was then inserted into malignant strictures of the bile duct and ampulla and left in place for 48 hours until 5000 rads were delivered to the tumor. The procedure was carried out in 14 patients (7 women, 7 men; mean age, 63.2 years; range, 46 to 86 years). Six patients were treated for cholangiocarcinomas, four with pancreatic carcinomas, and four with ampullary carcinomas. No complications occurred. The mean survival of the group was 7 months (range, 3 days to 27 months). This new technique provides both intraluminal brachytherapy and biliary drainage and is inserted intraduodenally across the papilla of Vater avoiding puncture of the liver and external hardware required by the percutaneous technique and hardware necessitated with a nasobiliary tube. Following removal of the iridium prosthesis, a large caliber endoprosthesis is inserted for continued decompression. Because of proven efficacy of endoprostheses, this new technique should be considered when intraluminal irradiation is indicated.

Adenoma, Bile Duct↗
PubMedDate not supplied

Laser versus laser plus afterloading with iridium-192 in the palliative treatment of malignant stenosis of the esophagus: a prospective, randomized, and controlled study.

Thirty-nine patients with malignant stenoses of the esophagus (22 adenocarcinomas, 17 squamous cell carcinomas) were treated either with Nd:YAG laser recanalization alone (N = 20) or with laser recanalization and subsequent endoluminal afterloading irradiation with iridium-192 at a dose of 3 x 7 Gy (6 x 7 Gy). Squamous cell carcinoma patients in the afterloading group showed a prolonged dysphagia-free first interval (65 vs. 30 days, p less than 0.03), while patients with an adenocarcinoma did not share this benefit, and had a need for more frequent endoscopic procedures (p less than 0.05). The complication of esophagitis was only seen following afterloading treatment (21%, N = 4). Re-stenosis occurred in all patients. Neither the duration of relative dysphagia nor survival time was prolonged after endoluminal irradiation in adenocarcinoma or squamous cell carcinoma patients. After prior laser recanalization, palliative afterloading treatment with iridium-192 would seem helpful only in cases of squamous cell carcinoma with a high performance status with the aim of prolonging the first dysphagia-free interval.

Adenocarcinoma↗
PubMed1985

Treatment of bladder tumors by iridium 192 implantation. The Créteil technique.

The technique and results of a treatment protocol for bladder cancer combining low dose pre-operative external beam irradiation followed by external iliac nodal dissection, limited partial cystectomy and curietherapy with iridium 192 are described. In 55 patients treated from 1971 to 1979, 37/45 (67%) are alive NED at 5 years--23/31 pT1, 10/14 pT2, 4/10 pT3--with 9/55 bladder recurrences at 5 years--7/31 pT1, 1/14 pT2, 1/10 pT3. Only two patients (total cystectomy) have not retained a functional bladder. These favorable results have been obtained in a carefully selected population; our indications for the technique being T1, T2, T3a tumors with a total surface area not exceeding 5 cm, not involving the bladder neck and unifocal or in some cases plurifocal, but closely grouped. The advantages and precise details of each stage of the technique will be described and compared with large series in which radium 226 is utilized and results of curietherapy will be compared with other modalities of treatment employed under similar circumstances for similar patient groups. We feel that curietherapy has certain advantages over other methods in the treatment of bladder cancer and that an afterloading technique employing iridium 192 wires permits the curietherapy to proceed under optimal conditions, allowing combination with partial cystectomy, optimal placement of sources, precise radiographic control and dosimetry, dose reduction in many cases, optimal conditions of radioprotection and widening of the indications for the technique.

Brachytherapy↗
PubMed1985

The treatment of squamous cell carcinoma of the nasal vestibule with interstitial iridium implantation.

From April 1981 to April 1984, 22 patients, all male, with a squamous cell carcinoma of the nasal vestibule were treated in the Rotterdam Radio-Therapeutic Institute with an interstitial iridium implantation alone or with a combination of external radiation and an interstitial iridium implantation. Median follow-up time was 26 months. One patient with a very large undifferentiated tumour developed local recurrences and regional metastases as well. No other patient had a local recurrence, regional or distant metastasis. Complications were only minor.

Aged↗
PubMed1998

Interstitial iridium-192 implantation combined with external radiotherapy in anal cancer: ten years experience.

PURPOSE: To report our experience in the use of interstitial iridium-192 implantation combined with external radiotherapy in anal cancer. METHODS AND MATERIALS: From 1984 to 1994, 79 patients with anal cancer were treated with radical intent using radiotherapy (plus chemotherapy) at Beatson Oncology Centre, Glasgow, Scotland. The mean and median age at presentation were 68 and 70 years, respectively (range 34-85) with a male-to-female ratio of 0.39. The histologic distribution was as follows: 48 squamous, 16 basaloid, 14 adenocarcinoma, and 1 basal cell carcinoma. The T stages were: 8 T1, 40 T2, 26 T3, and 5 T4 lesions. Twelve (15%) patients had nodal involvement at presentation. All patients underwent interstitial implantation using iridium-192 as part of the initial treatment. Seventy-six patients were treated with external radiotherapy followed by implant with a mean delay of 37 days after the end of radiotherapy. Twelve patients also received chemotherapy with 5-fluorouracil and mitomycin-C concurrently with external radiotherapy. Follow-up ranged from 6 to 123 months, with a median of 37 months. RESULTS: Seventy-nine patients were analyzed to assess local control, survival, and complications. A complete response rate of 91% (72 of 79) was achieved after planned radiation treatment. At the end of external radiotherapy, 29% (22 of 76) had achieved complete response, 58% (7 of 12) with chemotherapy and 23% (15 of 64) without it. Local control was achieved in 62 of 79 (78%) patients and 8 of 17 (47%) local failures were salvaged by abdominoperineal resection. Five patients developed inguinal node failure; four of these were salvaged. Overall, 10% of all patients developed distant metastasis as the first site of failure and 25% failed at any site after salvage therapy. Time to unsalvageable relapse was significantly different on comparing T stage (p = 0.005) and histology (p = 0.029) of tumor. Major complications requiring surgical intervention were seen in six (7.5%) patients. Anal function preservation with local control was possible in 56 of 79 (71%) patients. CONCLUSION: We report excellent results with radiotherapy in T1 and T2 lesions. The role of chemoradiotherapy as radical treatment of anal cancer should be defined in the context of locally advanced tumors.

Adenocarcinoma↗
PubMed1986

Comparison of ultrashort-lived iridium-191m with technetium-99m for first pass radionuclide angiocardiographic evaluation of right and left ventricular function in adults.

Ultrashort-lived iridium-191m (Ir-191m, physical half-life = 5.0 seconds) has been used in angiocardiography, primarily in pediatric patients. A theoretical obstacle to more widespread use of Ir-191m is the belief that its physical half-life is too short to permit evaluation of left ventricular function in adult patients. To evaluate its usefulness in adults, first pass ejection fractions of the left and right ventricles determined with use of Ir-191m and technetium-99m (Tc-99m) were compared in 33 adult patients. An osmium-191m----iridium-191m (Os-191----Ir-191m) generator was employed to deliver doses of 150 to 250 mCi (5.5 to 9.2 GBq) of Ir-191m for intravenous injection. The whole body radiation absorbed dose with Ir-191m was 15 to 25 mrad. High quality angiocardiograms were obtained with both Tc-99m and Ir-191m. Total counts per image for the right ventricle were 51,000 +/- 8,000 (mean +/- SD) for Ir-191m and 30,000 +/- 8,000 for Tc-99m. The left ventricular counts were comparable for both radiotracers (25,000 +/- 7,000 for Ir-191m and 25,000 +/- 8,000 for Tc-99m). Right ventricular ejection fractions were similar: 44 +/- 8% for Ir-191m and 47 +/- 9% for Tc-99m. The correlation coefficient was 0.93 with a standard deviation of the regression of 3.1% ejection fraction units. The left ventricular ejection fractions were also similar: 45 +/- 14% for Ir-191m and 46 +/- 13% for Tc-99m. The left ventricular ejection fraction correlation coefficient was 0.96 with a standard deviation of the regression of 3.7%.(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗
PubMed1998

Treatment of squamous cell carcinomas of the floor of the mouth and tongue by interstitial high-dose-rate irradiation using iridium-192.

The results are presented of afterloading high-dose-rate-radiation with iridium-192 in 34 patients with squamous cell carcinomas of the floor of the mouth and tongue. Some patients were also treated surgically or given percutaneous radio- or chemotherapy. At the time of diagnosis, 28.0% had a T2 tumour, 41.9% a T3 tumour and 30.1% a T4 tumour, 41.2% had positive lymph nodes and 2.9% distant metastases. The response rate was 64.7%, 26.5% of which were complete remissions and 38.2% partial remissions. In 61.8% of cases, the tumour was recurrent and responded with a rate as high as 57.2%, 23.9% of which were complete remissions and 33.3% partial remissions. Survival times were dependent upon therapy results. The mean survival of patients with complete remission was 40.3 months, with partial remission 16.1 months as opposed to 7.2 and 3.5 months respectively in patients showing no change or progressive disease. It can be concluded that afterloading therapy using high-dose-rate-radiation with iridium-192 achieves good palliative results and should be looked at as a supplementary treatment modality for squamous cell carcinomas of the floor of the mouth and tongue.

Adult↗
PubMed1991

Radiotherapy after conservative surgery for breast cancer: selective use of iridium-192 wire boost to tumour bed in high risk patients.

The results of treatment for 51 patients referred for radiotherapy after local excision of an 'early' breast carcinoma are reviewed. The patients were considered to be at particularly high risk of local recurrence due to the presence of one or more adverse histological features, most commonly microscopic involvement of resection margins. The patients received a course of whole-breast irradiation (40 Gy in 15 fractions over 3 weeks) but instead of following this with a routine photon or electron tumour-bed boost (15 Gy in five fractions) these patients received an iridium-192 wire implant, giving a tumour-bed boost of 25 Gy over approximately 3 days. After a median follow-up of 38 months, five patients have recurred locally within the breast, giving an actuarial breast recurrence-free survival of 87.8% at 8 years. Four patients have died of metastatic breast cancer, none of whom had uncontrolled local disease. Cosmesis was good or excellent in 76% of cases. The presence of microscopic tumour at resection margins or other adverse histological features is not, therefore, necessarily an indication for further surgery, as a good level of local control can still be achieved with radiotherapy providing a relatively high-dose tumour-bed boost is employed using an iridium-192 wire implant.

Adult↗