Reno, a European postmarket surveillance registry, confirms effectiveness of coronary brachytherapy in routine clinical practice

Developing a Lymphatic Surgery Program: A First-Year Review

BACKGROUND

Lymphedema is a chronic condition that carries a significant physical, psychosocial, and economic burden. The authors' program was established in 2017 with the aims of providing immediate lymphatic reconstruction in high-risk patients undergoing lymphadenectomy and performing delayed lymphatic reconstruction in patients with chronic lymphedema. The purpose of this study was to describe the authors' clinical experience in the first year.

METHODS

A retrospective review of our clinical database was performed on all individuals presenting to the authors' institution for lymphatic surgery consideration. Patient demographics, clinical characteristics, and surgical management were reviewed.

RESULTS

A total of 142 patients presented for lymphatic surgery evaluation. Patients had a mean age of 54.8 years and an average body mass index of 30.4 kg/m. Patients with lymphedema were more likely to be referred from an outside facility compared to patients seeking immediate lymphatic reconstruction (p < 0.001). For patients with lymphedema, the most common cause was breast cancer related. Thirty-two percent of all patients evaluated underwent a lymphatic procedure. Of these, 32 were immediate lymphatic reconstructions and 13 were delayed lymphatic reconstructions. In the authors' first year, 94 percent of eligible patients presenting for immediate lymphatic reconstruction underwent an intervention versus only 38 percent of eligible lymphedema patients presenting for delayed lymphatic reconstruction (p < 0.001).

CONCLUSIONS

First-year review of our lymphatic surgery experience has demonstrated clinical need evidenced by the number of patients and high percentage of outside referrals. As a program develops, lymphatic surgeons should expect to perform more time-sensitive immediate lymphatic reconstructions, as evaluation of chronic lymphedema requires development of a robust team for workup and review.

Frequency and risk factors for arm lymphedema after multimodal breast-conserving treatment of nodal positive breast Cancer - a long-term observation

Background

Arm-lymphedema is a major complication after breast cancer. Recent studies demonstrate the validity of predicting Breast Cancer Related Lymphedema (BCRL) by self-reports. We aimed to investigate the rate of BCRL and its risk factors in the long-term using self-reported symptoms.

Methods

Data was collected from 385 patients who underwent multimodal therapy for nodal positive breast cancer, including breast conserving surgery, axillary dissection, and local or locoregional radiotherapy. Two validated questionnaires were used for the survey of BCRL (i.e. LBCQ-D and SDBC-D). These were analysed collectively with retrospective data of our medical records.

Results

23.5% (n = 43) suffered a permanent BCRL (stage II-III) after a median follow-up time of 10.1 years (4.9–15.9 years); further 11.5% (n = 23) reported at least one episode of reversible BCRL (Stage 0-I) during the follow-up time. 87.1% of the patients with lymphedema developed this condition in the first two years. Adjuvant chemotherapy was a significant risk factor for the appearance of BCRL (p = 0.001; 95%-CI 7.7–10.2).

Conclusions

Breast cancer survivors face a high risk of BCRL, particularly if axillary dissection was carried out. Almost 90% of BCRL occurred during the first two years after radiotherapy. Self-report of symptoms seems to be a suitable instrument of early detection of BCRL.

Multiscale nonlinear microscopy and widefield white light imaging enables rapid histological imaging of surgical specimen margins

The ability to histologically assess surgical specimens in real-time is a long-standing challenge in cancer surgery, including applications such as breast conserving therapy (BCT). Up to 40% of women treated with BCT for breast cancer require a repeat surgery due to postoperative histological findings of close or positive surgical margins using conventional formalin fixed paraffin embedded histology. Imaging technologies such as nonlinear microscopy (NLM), combined with exogenous fluorophores can rapidly provide virtual H&E imaging of surgical specimens without requiring microtome sectioning, facilitating intraoperative assessment of margin status. However, the large volume of typical surgical excisions combined with the need for rapid assessment, make comprehensive cellular resolution margin assessment during surgery challenging. To address this limitation, we developed a multiscale, real-time microscope with variable magnification NLM and real-time, co-registered position display using a widefield white light imaging system. Margin assessment can be performed rapidly under operator guidance to image specific regions of interest located using widefield imaging. Using simulated surgical margins dissected from human breast excisions, we demonstrate that multi-centimeter margins can be comprehensively imaged at cellular resolution, enabling intraoperative margin assessment. These methods are consistent with pathology assessment performed using frozen section analysis (FSA), however NLM enables faster and more comprehensive assessment of surgical specimens because imaging can be performed without freezing and cryo-sectioning. Therefore, NLM methods have the potential to be applied to a wide range of intra-operative applications.

MRI sequences for the detection of individual lymph nodes in regional breast radiotherapy planning

OBJECTIVE

In regional radiotherapy (RT) for patients with breast cancer, lymph node (LN) targets are delineated on CT, defined by anatomical boundaries. By identifying individual LNs, MRI-based delineations may reduce target volumes and thereby toxicity. We optimized MRI sequences for this purpose. Our aim was to evaluate the techniques for LN delineation in RT planning.

METHODS

Supine MRI was explored at 1.5 T in RT position (arms in abduction). 5 MRI techniques were optimized in 10 and evaluated in 12 healthy female volunteers. The scans included one T1 weighted (T1w), three T2 weighted (T2w) and a diffusion-weighted imaging (DWI) technique. Quantitative evaluation was performed by scoring LN numbers per volunteer and per scan. Qualitatively, scans were assessed on seven aspects, including LN contrast, anatomical information and insensitivity to motion during acquisition.

RESULTS

Two T2w fast spin-echo (FSE) methods showed the highest LN numbers (median 24 axillary), high contrast, excellent fat suppression and relative insensitivity to motion during acquisition. A third T2w sequence and DWI showed significantly fewer LNs (14 and 10) and proved unsuitable due to motion sensitivity and geometrical uncertainties. T1w MRI showed an intermediate number of LNs (17), provided valuable anatomical information, but lacked LN contrast.

CONCLUSION

Explicit LN imaging was achieved, in supine RT position, using MRI. Two T2w FSE techniques had the highest detection rates and were motion insensitive. T1w MRI showed anatomical information. MRI enables direct delineation of individual LNs.

ADVANCES IN KNOWLEDGE

Our optimized MRI scans enable accurate target definition in MRI-guided regional breast RT and development of personalized treatments.

Identification of Prognostic Risk Factors for Transient and Persistent Lymphedema after Multimodal Treatment for Breast Cancer

PURPOSE

The purpose of this study is to identify risk factors for transient lymphedema (TLE) and persistent lymphedema (PLE) following treatment for breast cancer.

MATERIALS AND METHODS

A total of 1,073 patients who underwent curative breast surgery were analyzed. TLE was defined as one episode of arm swelling that had resolved spontaneously by the next follow-up; arm swelling that persisted over two consecutive examinations was considered PLE.

RESULTS

At a median follow-up period of 5.1 years, 370 cases of lymphedema were reported, including 120 TLE (11.2%) and 250 PLE (23.3%). Initial grade 1 swelling was observed in 351 patients, of which 120 were limited to TLE (34%), while the other 231 progressed to PLE (66%). All initial swelling observed in TLE patients was classified as grade 1. In multivariate analysis, chemotherapy with taxane and supraclavicular radiation therapy (SCRT) were associated with development of TLE, whereas SCRT, stage III cancer and chemotherapy with taxane were identified as risk factors for PLE (p < 0.05). The estimated incidence of TLE among initial grade 1 patients was calculated using up to three treatment-related risk factors (number of dissected axillary lymph nodes, SCRT, and taxane chemotherapy). The approximate ratios of TLE and PLE based on the number of risk factors were 7:1 (no factor), 1:1 (one factor), 1:2 (two factors), and 1:3 (three factors).

CONCLUSION

One-third of initial swelling events were transient, whereas the other two-thirds of patients experienced PLE. Estimation of TLE and PLE based on known treatment factors could facilitate prediction of this life-long complication.

Breast Cancer-Related Lymphedema after Neoadjuvant Chemotherapy

Purpose

The risk for lymphedema (LE) after neoadjuvant chemotherapy (NCT) in breast cancer patients has not been fully understood thus far. This study is conducted to investigate the incidence and time course of LE after NCT.

Materials and Methods

A total of 313 patients with clinically node-positive breast cancer who underwent NCT followed by surgery with axillary lymph node (ALN) dissection from 2004 to 2009 were retrospectively analyzed. All patients received breast and supraclavicular radiation therapy (SCRT). The determination of LE was based on both objective and subjective methods, as part of a prospective database.

Results

At a median follow-up of 5.6 years, 132 patients had developed LE: 88 (28%) were grade 1; 42 (13%) were grade 2; and two (1%) were grade 3. The overall 5-year cumulative incidence of LE was 42%. LE first occurred within 6 months after surgery in 62%; 1 year in 77%; 2 years in 91%; and 3 years in 96%. In a multivariate analysis, age (hazard ratio [HR], 1.66; p < 0.01) and the number of dissected ALNs (HR, 1.68; p < 0.01) were independent risk factors for LE. Patients with both of these risk factors showed a significantly higher 5-year cumulative incidence of LE compared with patients with no or one risk factor (61% and 37%, respectively; p < 0.001). The addition of adjuvant chemotherapy did not significantly correlate with LE.

Conclusion

LE after NCT, surgery, and SCRT developed early after treatment, and with a high incidence rate. More frequent surveillance of arm swelling may be necessary in patients after NCT, especially during the first few years of follow-up.

Manual lymph drainage when added to advice and exercise may not be effective in preventing lymphoedema after surgery for breast cancer

Summary of: Devoogdt N et al (2011) Effect of manual lymph drainage in addition to guidelines and exercise therapy on arm lymphoedema related to breast cancer: randomized controlled trial. BMJ 343: d5326. [Prepared by Nicholas Taylor, CAP Editor.]

QUESTION

Does manual lymph drainage prevent lymphoedema in patients who have had surgery for breast cancer?.

DESIGN

Randomised, controlled trial with concealed allocation and blinded outcome assessment.

SETTING

A multidisciplinary breast centre of a tertiary hospital in Belgium.

PARTICIPANTS

Patients were eligible to be included if they received unilateral surgery with axillary node dissection for breast cancer, and agreed to participate. Randomisation of 160 participants allocated 79 to the intervention group and 81 to a control group.

INTERVENTIONS

Both groups received guidelines about the prevention of lymphoedema in the form of a brochure, and exercise therapy involving supervised individualised 30 minute sessions - initially twice a week, reducing to once fortnightly as patients progressed. Participants in both groups were also asked to perform exercises at home twice/day. In addition, the intervention group received 40 sessions of manual lymph drainage over 20 weeks with each session lasting 30 minutes and performed by trained therapists.

OUTCOME MEASURES

The primary outcomes were the cumulative incidence of and the time to develop arm lymphoedema (defined as a 200 ml increase) as measured with the water displacement method with measures taken at baseline and 1, 3, 6, and 12 months after surgery. Secondary outcome measures were lymphoedema measured with the arm circumference method, health-related quality of life using the SF-36 scale, and a patient reported questionnaire to score the presence of subjective arm lymphoedema.

RESULTS

154 participants (96%) completed the study at 12 months. At 12 months the incidence of lymphoedema in the intervention group (n=18, 24%) was similar to the incidence of lymphoedema in the control group (n = 15, 19%, OR 1.3, 95% CI 0.6 to 2.4); also there was no difference in incidence at 3 or 6 months. There was no difference between the groups in the time taken to develop lymphoedema, and no difference between the groups in any secondary outcome measure.

CONCLUSION

The application of manual lymph drainage after axillary node dissection for breast cancer in addition to providing guidelines and exercise therapy did not prevent lymphoedema in the first year after surgery.

Should adjuvant radiotherapy to the supraclavicular fossa be routinely given in patients with breast conservative treatment?

BACKGROUND

To analyze the overall outcome, supraclavicular fossa (SCF) recurrence rate, and pattern of failure in breast cancer patients treated with conservative surgery and adjuvant radiotherapy excluding SCF treatment.

METHODS

A total of 143 patients were enrolled in the study. Ninety-two percent of patients were stages I and II, and 8% were stage III. The median age was 44 years, and 31% of patients were </=40 years old. Radiotherapy was delivered to the ipsilateral breast excluding the SCF.

RESULTS

The 5-year overall survival rate of the cohort was 95%, and disease-free survival rate was 91%. The cumulative incidence of SCF recurrence was 18% in patients with involved axillary nodes (N) >/= 4, and 0.8% in patients with N < 4. The 5-year SCF-recurrence-free survival in patients with N >/= 4 and N < 4 was 80% and 99%, respectively (P < 0.001). N >/= 4 was the only independent predictor for locoregional control (P = 0.045), disease-free survival (P = 0.001), and overall survival (P = 0.008) in multivariate analysis.

CONCLUSIONS

Women with N >/= 4 have a significantly higher risk of SCF recurrence and poorer survival. The SCF might be safely spared in patients with N < 4, but should be routinely included in the radiotherapy design for those with N >/= 4.

Drug-Eluting Stents

The introduction of percutaneous transluminal coronary angioplasty has revolutionized the field of cardiology by providing patients with coronary artery disease immediate and effective therapy. Overshadowing the early success of angioplasty was the high rate of angiographic restenosis and recurrent symptoms at 6 months. The use of stents reduced the incidence of restenosis; however, the rise in the number of patients undergoing percutaneous interventions produced a new problem of restenosis occurring within the stent: in-stent restenosis (ISR). Mechanical approaches, including directional and rotational atherectomy and systemic pharmacotherapy, have failed to demonstrate a reduction in ISR in randomized clinical trials. Intravascular brachytherapy is currently the only approved therapy for ISR, although this treatment has numerous unresolved questions and is not effective in a large percent of patients. Drug-eluting stents have reduced the incidence of restenosis by providing localized therapy to the targeted lesion without systemic toxicity. The purpose of this review is to synthesize data from major clinical trials involving the 2 most successful agents used in the prevention of restenosis: sirolimus and paclitaxel. The cellular and molecular mechanisms of both ISR and restenosis postangioplasty derived from animal models will be introduced. Second, an overview of 3 alternate interventions that attempt to reduce the rates of restenosis is presented. Finally, the major randomized, controlled trials involving sirolimus and paclitaxel are described, and their clinical implications and use as a possible solution in the prevention of restenosis is discussed.

Comparison between drug-eluting stents and beta-radiation for the treatment of diffuse in-stent restenosis: clinical and angiographic outcomes

BACKGROUND

Initial reports on drug-eluting stents (DES) for the treatment for in-stent restenosis (ISR) show very good outcomes. Nevertheless, few data are available on direct comparison with intracoronary brachytherapy (IBT). The aim of this study was to compare brachytherapy and DES in treatment of diffuse ISR.

METHODS

One hundred forty-one consecutive patients with diffuse ISR were treated with IBT (68 patients; beta (90Sr/90Y) emitters) or with DES (73 patients; 32 with sirolimus-eluting and 41 with paclitaxel-eluting stents). Angiographic and clinical follow-up was scheduled within 9 months.

RESULTS

The first 74 lesions were treated with IBT (group 1) and the latter 74 with DES (group 2). The two groups were well matched for clinical/angiographic characteristics. At follow-up, restenosis rates were 37.8% (28/74) in IBT group and 14.9% (11/74) in DES group (P = .0028). A diffuse pattern of recurrence was more frequent after IBT (20/74 vs 6/74, P = .005). A worse outcome after IBT was associated with the "edge effect," accounting for most failures. Recurrence within the original restenotic stent was similar in both groups (12.9% vs 14.9% in groups 1 and 2 respectively, P = .8).

CONCLUSIONS

Drug-eluting stents are more effective than IBT with beta-irradiation in reducing recurrence rates after treatment of diffuse ISR. In case of failure, the pattern of restenosis is more benign after treatment with DES.

A comparison of four diagnostic criteria for lymphedema in a post-breast cancer population

BACKGROUND

Breast cancer survivors are at life-time risk of developing lymphedema (LE). The goal of this research was to describe LE incidence over time among women treated for breast cancer.

METHODS AND RESULTS

Limb volume changes (LVC) were evaluated by two measurement methods, circumferences and perometry, among 118 participants followed preoperative to 12 months postdiagnosis. Four diagnostic criteria were used: 200 mL perometry LVC; 10% perometry LVC; 2 cm circumferential increase; and report of heaviness or swelling, either "now" or "in the past year." Using 200 mL, the estimated LE rate was 24% (95% CI = 17%-32%) at 6 months, and 42% (31%-53%) at 1 year. Using 10% LVC, the estimated LE rate was 8% (2%-13%) at 6 months, and 21% (12%-30%) at 1 year. Using 2 cm, the estimated LE rate was 46% (36%-56%) at 6 months, and 70% (60%-79%) at 1 year. Based on reported symptoms of heaviness or swelling, the estimated LE rate was 19% (11%-26%) at 6 months, and 40% (30-59%) at 1 year.

CONCLUSIONS

In the absence of a gold standard, we can only say that the different LE definitions are not equivalent, but cannot say which is "best". From this data, it appears that 10% LVC corresponds to a more conservative definition, whereas the 2 cm difference corresponds to a more liberal definition. These preliminary findings also document the importance of baseline (preoperative) anthropometric and symptom data and monitoring of changes over time. Further investigation of LE occurrence over an extended time period is warranted.

Psychologic and social sequelae of secondary lymphedema: a review

BACKGROUND

The psychological and social sequelae of secondary lymphedema (SLE) have been an underrecognized and little-researched complication of treatment for breast carcinoma. The reported incidence and prevalence of SLE varied widely (0-48%). Reported reasons for the differences are related to the lack of standard diagnostic and universal assessment criteria.

METHODS

A comprehensive, computerized search was performed. All combinations of the following keywords were used: arm lymphedema, arm swelling, breast cancer, psychological and social, and quality of life (QOL). Eighteen studies were identified.

RESULTS

The literature supported the view that SLE leads to psychological and social sequelae. Psychological sequelae included frustration, distress, depression and anxiety. Social sequelae comprised changes in role function, lack of social support and pain and disability. Pain was a significant predictor of psychological and social morbidity. These experiences resulted in diminution of QOL, particularly psychological and social health. This was particularly worrisome because women must attend daily to the precautions and treatments for SLE.

CONCLUSIONS

Researchers should use psychological and social measures along with physiologic parameters when evaluating the impacts of SLE. Clinicians should work to develop standardized primary prevention programs and limb circumference should be measured at the time of breast carcinoma diagnosis. Gaps in knowledge related to intra/interethnic diversity, poverty, and comorbidities of women with breast carcinoma-related SLE need to be explored. The combined efforts of researchers and clinicians would reinforce awareness and knowledge for women at risk and provide important baseline data for research and practice.

Brachytherapy for restenosis after stenting for coronary artery disease: its role in the drug-eluting stent era

PURPOSE OF REVIEW

Recent years have brought remarkable changes to the field of interventional cardiology. The need for repeat intervention due to restenosis, the most vexing long-term failure of percutaneous coronary intervention, has been significantly reduced owing to the introduction of two major advances, the vascular brachytherapy (VBT) and the drug-eluting stents (DES).

RECENT FINDINGS

Vascular brachytherapy has demonstrated its efficacy in limiting recurrence of existing in-stent restenosis. The past 2 years have sealed its reputation, with a variety of studies demonstrating its superiority over conventional therapy in challenging patient subsets with high risk for restenosis recurrence. Moreover, the long-term follow-up confirmed durability of this therapy, and the failures of VBT were characterized as easy to treat. Conversely, DES have shown spectacular efficacy at primarily preventing the first restenosis episode following the initial stent placement. Consequently, the role of VBT may be minimized, as the overall need for repeat revascularization is diminished as a result of the wide acceptance of DES. Furthermore, if the capacity of DES to treat in-stent restenosis is confirmed in randomized trials, they may eventually supersede VBT as the therapy of choice for in-stent restenosis.

SUMMARY

At present, VBT is the proven and durable therapeutic choice for patients with complex, diffuse in-stent restenosis who would otherwise have a very poor prognosis for long-term event-free survival. DES have emerged as remarkably effective in minimizing the first restenosis occurrence; they also represent a promising and competitive alternative to VBT for the treatment of in-stent restenosis.

Intracoronary radiation therapy using a novel beta emitter for in-stent restenosis

BACKGROUND

Intracoronary beta-radiation therapy reduces in-stent restenosis (ISR). We aimed to determine the safety and feasibility of intracoronary radiation therapy (IRT) utilizing tungsten (188W), a beta emitter.

METHODS

A total of 30 patients with angiographic evidence of ISR in a previously treated native coronary artery underwent percutaneous coronary intervention (PCI; balloon angioplasty, ablation by atherectomy, or laser angioplasty). After the intervention, a noncentered delivery catheter with a side guide 0.014-in. wire carrying a tungsten (188W) coil, with an active length of 33 mm, was inserted. Patients were randomized to a radiation dose of 18, 22, or 25 Gy at 2 mm from the center of the source. Aspirin and Plavix, at 300 mg loading dose, were administered prior to intervention. Plavix 75 mg/day was prescribed for 6 months after the procedure.

RESULTS

At 6 months follow-up, the overall binary angiographic restenosis rate was 18.8%. Target vessel revascularization (TVR) was 23% and target lesion revascularization related major adverse cardiac events (TLR-MACE) was 13.3%, without any intergroup differences. A comparison with the original Washington Radiation for In-stent restenosis Trial (WRIST) radiation cohort utilizing an 192Iridium source (prescription dose 15 Gy at 2 mm from the source) showed similar TVR and TLR-MACE rates of 30% and 18%, respectively. The TVR and TLR-MACE rates in the WRIST placebo cohort were 70% and 66%, respectively.

CONCLUSIONS

Vascular brachytherapy with tungsten (188W) is feasible and safe. The 6-month clinical outcomes are similar to the original WRIST radiation group.

Can hyperbaric oxygen therapy reduce breast cancer treatment-related lymphedema? A pilot study

OBJECTIVE

Arm lymphedema after surgery or radiation for breast cancer is common, causing pain and limitation of activities. Previous reports of hyperbaric oxygen (HBO) therapy for breast edema led us to consider the use of HBO therapy for arm lymphedema.

METHODS

Ten healthy postmenopausal women (age 58 +/- 5.7 years) with persistent (9.4 years +/- 9.1 years) arm lymphedema following breast cancer surgery and radiation (n = 10) plus chemotherapy (n = 7) received 20 HBO treatments (90 minutes at 2.0 ATA five times a week for 4 weeks). End points included changes in upper extremity volume, platelet counts, plasma levels of vascular endothelial growth factor (VEGF), and lymph angiogenic-associated vascular endothelial growth factor-C (VEGF-C). Lymphedema volume (LV) was defined as the volume of the unaffected arm subtracted from the volume of the affected arm.

RESULTS

We observed a 38% average reduction in hand lymphedema (-7.4 ml, 11.6 SD, range -30-+8 ml, p = 0.076, 95% confidence interval -15.7-0.9 ml) at the end of HBO, which was independent of changes in body weight. For those who benefited (n = 8), the reduction was persistent from the end of treatment to a final measurement an average of 14.2 months after the last HBO treatment. However, total LV did not change significantly. VEGF-C increased from baseline (p = 0.004) before treatment 20, suggesting HBO had begun to stimulate this growth factor.

CONCLUSIONS

Future studies should explore the effects of a greater number of HBO treatments on lymphedema, with more patients.

Predictors of 32P beta brachytherapy failure in patients with high-risk in-stent restenosis

BACKGROUND

The effectiveness of coronary radiation therapy for the treatment of in-stent restenosis (ISR) has been established in several randomized clinical trials. The efficacy of this treatment in the general population is less well established.

METHODS AND MATERIALS

We report our experience in 118 consecutive patients with nonselected high-risk ISR who had undergone successful percutaneous coronary intervention and brachytherapy with (32)P beta-irradiation and who were prospectively enrolled in a quantitative angiographic and clinical follow-up protocol at 7 months after the index procedure. The aim of this study was to investigate the independent predictor of angiographic restenosis after (32)P brachytherapy treatment.

RESULTS

Of the patients, 28.8% were diabetics. The mean lesion and mean radiated lengths were, respectively, 30.1 +/- 17.2 and 43.8 +/- 16.9 mm. The ISR pattern was diffuse in 96% of the treated lesions; in particular, 22.1% presented an occlusive pattern and 37.1% a proliferative pattern. At follow-up angiographic, restenosis and major adverse cardiac events (MACE) rates were, respectively, 20.8% and 29.6%. The univariate predictors of angiographic restenosis were procedural geographic miss, pattern IV ISR, manual pullback maneuver of the radiation source, preprocedural lesion percentage stenosis and preprocedural lesion MLD. At logistic regression analysis, only geographic miss and pattern IV ISR were independent predictors of post intracoronary radiation therapy (IRT) angiographic restenosis.

CONCLUSION

These data indicate that 7-month angiographic restenosis after (32)P IRT in complex patients with ISR is not a frequent event and is predicted mainly by an occlusive lesion at baseline and by procedural geographical miss.

Evolution of angiographic restenosis rate and late lumen loss after intracoronary beta radiation for in-stent restenotic lesions

The aim of this study was to investigate the time course of angiographic restenosis rate and late loss after successful percutaneous coronary intervention and vascular brachytherapy with beta-irradiation using strontium-90/yttrium-90 in 98 patients who were prospectively enrolled into a quantitative angiographic and clinical follow-up protocol at 6, 12, and 24 months after the index procedure, regardless of their symptom status. Actuarial restenosis rates measured 11.2 +/- 5% at 6 months of follow-up, 24.5 +/- 5% at 12 months, and 28.5 +/- 6% at 24 months, respectively. Late loss of the stent segment during the first 6 months measured 0.38 +/- 0.40 mm (6 to 12 months: 0.25 +/- 0.38 mm; 12 to 24 months: 0.16 +/- 0.32 mm), of the injured segment 0.27 +/- 0.21 mm (6 to 12 months: 0.21 +/- 0.26 mm; 12 to 24 months: 0.13 +/- 0.24 mm), of the irradiated segment 0.18 +/- 0.29 mm (6 to 12 months: 0.19 +/- 0.31 mm; 12 to 24 months: 0.11 +/- 0.27 mm), and of the analysis segment 0.18 +/- 0.36 mm (6 to 12 months: 0.17 +/- 0.29 mm; 12 to 24 months: 0.11 +/- 0.20 mm). Restenosis after angioplasty and beta-irradiation of in-stent restenotic lesions is not complete within 6 months but is sustained with a gradual decrease over 24 months.

Brachytherapy for in-stent restenosis in general interventional practice: a single institution's experience using four radiation devices

BACKGROUND

The effectiveness of brachytherapy for the treatment of in-stent restenosis (ISR) has been established in a number of large randomized controlled trials. Efficacy of this therapy in general population is less well established.

METHODS AND MATERIALS

We report our experience of 207 patients, 236 coronary lesions, treated with brachytherapy between November 2000 and November 2002. All commercially available brachytherapy devices, as well as one investigational device, were utilized. This cohort was followed over 9 months and clinical outcomes were obtained with subsequent analysis of patient and lesion-specific characteristics.

RESULTS

Average treatment age was 62.5 years; 73% were male and the most frequent presentation was unstable angina (74%). All patients had successful delivery of radiation, with no in-hospital deaths. Novoste BetaCath device was used for 163 (65%) lesions, Cordis Checkmate for 56 (24%) lesions, Interventional Therapies device in 13 (8%) lesions, and Guidant Galileo in 4 lesions (3%). At a mean follow-up of 9.1 months, 78.7% were free of major adverse cardiac event (MACE). Twenty-one patients required repeat PTCA (10.1%), 19 had CABG (9.2%), 3 had MI (1.4%), and there was 1 death (0.5%). Unadjusted MACE rates for each device were 21% for Novoste, 28% for Checkmate, 8% for Interventional Therapies, and 50% for Galileo. Lesion length, minimal lumen diameter, renal failure, diabetes, and smoking did not predict treatment failure; only age was inversely correlated with MACE (P=.002).

CONCLUSION

When applied across a spectrum of patients, lesions, and devices, brachytherapy retains its effectiveness with outcomes similar to those reported in randomized clinical trials.

Intravascular brachytherapy using 90Sr for saphenous vein grafts having diameters ranging from 2.0–5.0 mm

PURPOSE

Symptomatic coronary artery disease is routinely treated with angioplasty and stenting. Unfortunately, treatment failure in the form of in-stent restenosis (ISR) occurs relatively frequently. Intravascular brachytherapy (IVBT) is a safe and effective method proven to markedly reduce the rate of ISR in native coronary arteries. The commercially available devices for IVBT are not FDA-approved for treatment of saphenous vein grafts (SVG). This article presents calculated dosimetry for treatment of a wide range of SVG, in addition to further evaluating the dose homogeneity for native coronary arteries.

METHODS AND MATERIALS

AAPM Task Group 43 and 60 formalisms permitted dose calculations for a wide range of vessel internal diameters (phi) in both native coronary arteries and SVG. Doses were analytically calculated for the Novoste Beta-Cath 5.0 French (F) treatment devices (30, 40, and 60 mm sourcetrains) when employed for the treatment of native vessels with 2.7 <or= phi <or= 4.0 mm and for SVG with 2.0 <or= phi <or= 5.0 mm. This latter range of phi was segmented into 7 bins to facilitate rapid clinical implementation with minimal errors. Calculations of dose and dose rate for the 3.5 F devices were also performed. Dose inhomogeneity in the form of dose maxima and minima were calculated for the 3.5 and 5.0 F catheters, with the 30, 40, and 60 mm sourcetrains, and for 2.0 <or= phi <or= 5.0 mm.

RESULTS

The calculated doses rates for the 30 mm device were in agreement (typically +/- 0.3%) with measured dose rates. Reference dose calculations performed for SVG with 2.0 <or= phi <or= 5.0 mm were in alignment with those used for the more narrow range of native coronary arteries currently approved for IVBT. Errors associated with using a phi binning technique for simplifying clinical implementation did not exceed 15%, and were typically under 9%. The degree of dose inhomogeneity at a depth of 0.5 mm increased as phi increased, catheter size decreased, and sourcetrain length decreased, and was -42% and +101% relative to the prescribed dose for the 40 mm 5.0 F system with phi = 4.0 mm.

CONCLUSIONS

Use of 7 phi bins facilitates rapid clinical implementation of IVBT in the typical cardiac catheterization laboratory. While calculation of reference dose for treatment of large vessels is possible with established formalisms, the degree of dose inhomogeneity in light of current clinical results suggests further research is needed.

Beta emitter systems and results from clinical trials

Vascular brachytherapy has been established as the standard of care for the treatment of in-stent restenosis (ISR). Both beta and gamma emitters are currently in use for the prevention of ISR recurrence. The use of beta sources for vascular application is attractive from both the radiation exposure and safety points of view, and a wide variety of beta sources are available for this application. This review is intended to summarize the clinical trials utilizing beta emitter systems for the treatment of ISR and de novo lesions and their subsequent results.