Coronary artery radiation therapy for the prevention of restenosis after percutaneous coronary angioplasty, II: Outcomes of clinical trials

Endobronchial brachytherapy provides excellent long-term control of recurrent granulation tissue after tracheal stenosis

PURPOSE

To review the experience of using endobronchial brachytherapy (EBB) as a treatment for recurrent tracheal granulation tissue.

METHODS AND MATERIALS

Patients referred for EBB at the Rabin Medical Center for benign stenosis were reviewed with institutional review board approval. Patients underwent bronchoscopic resection of granulation tissue followed by insertion of self-expanding metallic stents. After stenting, repeat laser resection was done at least 1 week before brachytherapy. After CT simulation, patients had three-dimensional brachytherapy treatment planning. A single 10-Gy dose was prescribed to 1.0cm from the source and treatment was delivered using high-dose-rate afterloader with (192)Ir source. Patients were followedup with bronchoscopy every 3 months after the completion of therapy.

RESULTS

From November 2001 to January 2009, 29 patients were treated with EBB to prevent granulation tissue reformation. Median age was 70 years and 55% of patients were male. Ninety percent of patients were treated to the trachea and the remaining patients had stenoses in the main stem bronchi. The primary cause of stenosis was prolonged mechanical ventilation (76%). The median time from stent placement to brachytherapy was 69 days. Median active length of treatment was 7cm. With a median followup of 36 months, 66% (19 of 29) of patients remained free of granulation tissue. Forty-eight percent of patients have died, with all except 1 patient dying of their underlying condition. A single patient experienced death from tracheoesophageal fistula.

CONCLUSION

EBB is an effective and safe treatment to prevent recurrent granulation tissue formation after endobronchial resection and should be considered in patients who are unable to undergo surgical resection.

External beam radiotherapy in the treatment of extensive vascular malformation of the lower extremity refractory to surgery and interventional embolisation therapy

This patient case-study represents the introduction of radiotherapy in the management of extra-cranial vascular malformations, a topic with virtually no supported literature before our case study. In those patients refractory to established therapies and facing the inevitability of mutilating amputation, radiotherapy may be a viable option to preserve the limb.

Percutaneous coronary revascularization in diabetics: from balloon angioplasty to drug-eluting stents

Diabetic patients may have aggressive coronary disease with an excessive rate of restenosis and accelerated atherosclerotic progression. This article reviews the different modalities of percutaneous treatment and their results in the diabetic population, from the early days of balloon angioplasty to the current implementation of drug-eluting stents. As restenosis may be virtually eradicated in the near future, plaque progression remains the cornerstone for interventional cardiologists and the medical community. In this regard, attempts to modify life habits, and a more accurate control of the components of the metabolic syndrome should be the main therapeutic objective.

High-dose-rate brachytherapy of recurrent rectal adenocarcinoma presenting as a solitary intravascular metastasis of the iliac vein: a case report

PURPOSE

To describe a novel use of high-dose-rate intravascular brachytherapy in the first reported case of macroscopic metastatic rectal adenocarcinoma within a peripheral vein.

METHODS AND MATERIALS

Following thrombolytic therapy to ablate an overlying venous thrombosis, a vascular stent was deployed across the entire length of the tumor. Using the stent as a target, 4300 cGy was delivered to the tumor via megavoltage external beam radiation. This was followed by two weekly intravascular high-dose-rate 192Ir brachytherapy applications of 400 cGy each.

RESULTS

There is no evidence of recurrence in the treated vein at 43 months of follow-up.

CONCLUSIONS

In this unique case, a combination of external beam radiation therapy and intravascular brachytherapy provided effective control of a solitary intravascular metastasis from rectal carcinoma.

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: indications and management of adverse events

Intravascular brachytherapy has become the standard of care for the treatment of coronary in-stent restenosis after repeat angioplasty. More than 5000 patients have been treated as part of various clinical trials. Based on the results of the GAMMA I trial, the START ((90)Sr Treatment of Angiographic Restenosis Trial), and the INHIBIT (INtimal Hyperplasia Inhibition with Beta In-stent restenosis Trial), the Checkmate system using (192)Ir, the Betacath system using (90)Sr/Y, and the Galileo system using (32)P, have been approved for the treatment of in-stent restenosis. With a better understanding and application of radiation oncology concepts to vascular brachytherapy, problems such as edge failure are being overcome. The complication of late thrombosis has also become less significant with the elimination of restenting at the brachytherapy procedure, and the prolonged use of antiplatelet therapy. There are other competing modalities in the early phases of clinical trials. The durability of results, lack of any significant long-term complications and the confirmation of the efficacy in other sites will further consolidate the role of radiation in treating in-stent restenosis.

Drug-eluting stents: potential applications for peripheral arterial occlusive disease

Many different approaches have been evaluated to prevent restenosis in stents after vascular implantation. Currently, drug-eluting stents are extremely promising in suppressing neointimal hyperplasia. Various animal studies and randomized trials in humans have shown excellent results in terms of safety and efficacy during intermediate-term follow-up. This article will give an overview of experimental and clinical data of the different agents in published and ongoing trials.

[Brachytherapy for coronary restenosis: state of art in 2003]

Based on therapeutic approach for benign diseases, vascular brachytherapy decreases smooth vascular muscle cells proliferation and multiplication which lead to the formation of the neo-intima. The radioactive positive action affects arterial recoil due to post angioplasty vessel injury. Randomised studies has shown good angiographic results up to 6 months of follow-up, with 50% in-stent restenosis rate decrease and on the analysed segment as well. Decrease on Mace and TLR show statistically significance. Results don't correlate with emitter and bêta emitters had been introduced in France recently. Vascular brachytherapy is actually indicated for in-stent restenosis, there is no evidence to perform this treatment for de novo lesion. Geographic miss, source centering, late thrombosis and pullback procedure may interfere with treatment quality. IVUS allows best target volume determination to a higher quality level. Internationals guidelines such as Eva-Gec-Estro recommendations could increase treatment safety and enable development of an optimal technique.