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Venezia brachy applicator for cervical cancer

Brachytherapy

Brachytherapy veteran Jean-Michel Hannoun-Levi’s observations on intracavitary/interstitial gynecological brachytherapy and Elekta’s new Advanced Gynecological Applicator, Venezia

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Dr. Hannoun-Levi

Nice University’s Head of Radiation Therapy Department, Jean-Michel Hannoun-Levi, MD, PhD, has been involved in brachytherapy as far back as his first days as a radiation oncology resident at Leon Berard (Lyon) and Alexis Vautrin (Nancy) Cancer Centers, and has been fortunate to meet and work with renowned French brachytherapists Monique Pernot, Alain Gerbaulet and Jean-Pierre Gerard. These impactful experiences led him to a career in brachytherapy, serving as chief of the brachytherapy unit at Marseilles Cancer Center from 1996 to 2000. In 2000, he became head of the brachytherapy service at Nice University, over the ensuing years engaging in several prospective brachytherapy trials for breast, gynecological and prostate cancers. In gynecological brachytherapy alone, he has performed over 500 implantations.

In 2004, Dr. Hannoun-Levi began concentrating on the use of HDR brachytherapy for gynecological cancers. Successful brachytherapy of varying stages of cervical cancer has revolved around the selection of the appropriate applicator. Treating disease that has extended far into the parametrium and vagina has been challenging due to the limited reach of existing brachytherapy applicators. Dr. Hannoun-Levi has worked with Elekta on applicator designs that address this challenge and contributed his insights toward the development of the Advanced Gynecological Applicator Venezia.

Wavelength spoke with Dr. Hannoun-Levi about applicator designs and Venezia.

WL: What issues have you encountered with applicators designed to treat cervical cancer?

Dr. Hannoun-Levi: Over the years, I’ve observed that the standard ring applicator has limitations. Its use requires great skill, the dose escalation is limited and the organs-at-risk – mainly the bladder and rectum – can be exposed to increased radiation.

In addition, the insertion of a ring applicator in small pelvic anatomy can be quite challenging.

WL: I understand that these observations led your team at Nice University to consider a different applicator design – can you elaborate on that?

H-L: The solution we developed was a vaginal cylinder that would allow us to combine intracavitary and interstitial brachytherapy. In 2006, we began working with Elekta [Nucletron at the time] on a prototype that we called the Nice Gynecological Applicator [NGA]. During that year, Vienna University – working with Nucletron – published its work on the Vienna Ring Applicator, a device that incorporated interstitial needles around the intrauterine tandem.1 The Nice group published its first results with the NGA in brachytherapy in 2013.2

With Venezia you will be able to treat various stages of advanced cervical cancer

WL: What were the limitations of the NGA applicator and how did this device evolve?

H-L: In the case of locally advanced disease – tumors in the parametrium – if your choice was to use brachytherapy it was recommended to split the brachytherapy boost. The first implant was dedicated to the central disease and the second implant one or two weeks later was based on parametrium involvement. Regarding patient comfort and quality of life, as well as radiobiological considerations, it was debatable to accept this two-procedure process. But at the time it was not possible to do it another way.

However, since I performed transperineal interstitial brachytherapy during my residency to treat parametrial involvement, we formed a concept of a new NGA prototype that combined intracavitary and interstitial brachytherapy, using an Elekta perineal template to facilitate a transperineal approach to treat the tumors in the parametrium. This applicator would enable implants to treat both the central disease and parametrial extensions during the same procedure.3

WL: How has this improved NGA applicator worked?

H-L: We obtained some beautiful dose distributions – some of the best we can achieve in this situation – but to be honest, with this specific template we have to increase the number of implanted needles if we want to optimize the dose distribution. We agreed with Elekta to keep the concept of transperineal implants for the parametrium, but at the same time increasing the number of needles that can be implanted in the right area. That’s why the perineal template of the Venezia applicator is designed differently compared to the perineal template of the NGA.

WL: How is the Venezia perineal template different?

H-L: The Venezia template has many more holes – 134 in total versus six in the NGA – meaning that the clinician has more options to implant needles transperineally. Clearly, there will be extremely few clinical situations that require implanting that many needles in this area. However, if you want to cover the parametrium area we will be able to implant 6, 8, 9 or 10 needles in the right area, and – at the time of the dose distribution analysis – we will choose the right number of needles and the correct needles we want to use for treatment delivery. The concept of increasing the number of implanted needles at the beginning of the process is an interesting concept and offers more flexibility for achieving the preferred dosimetry.

WL: What are the advantages of the Venezia applicator in your mind?

H-L: The ability to use Venezia for both intracavitary and interstitial brachytherapy makes it a more universal applicator. With Venezia you will be able to treat various stages of advanced cervical cancer. If you need to treat very localized disease – T1B1 of T1B2 – it is possible. If you want to treat a larger tumor it is also possible, using exactly the same applicator. For the radiation oncologist and for the patient, of course, it will be more comfortable, more accurate and you will need to buy just one applicator.

WL: What challenges do you see for the use of brachytherapy in treating gynecological cancers?

H-L: Currently, brachytherapy is not widely used. For cervical cancer, in particular, some clinics prefer to use external beam or other stereotactic radiotherapies instead of brachytherapy, even if the clinical evidence indicates that brachytherapy is the best treatment we can provide in terms of local control and overall survival. The challenge will be making sure an applicator like Venezia is easy to use and easy to teach. Physicians who use a dedicated applicator – a Utrecht applicator for instance – might find it difficult to switch to another applicator, like Venezia, even if this applicator seems more useful for treating locally advanced stages.

WL: What is the solution?

H-L: It will be important to follow teams who begin using Venezia, to teach these brachytherapists the right way to use this applicator in two, three or four cases. This is really important, because if not executed correctly the concept of intracavitary/interstitial and the concept of a transperineal approach could appear less accurate compared to the two-phase method, even though Venezia is clearly a better and more versatile applicator.

I believe that Elekta with BrachyAcademy is committed to teaching the proper use of Venezia – at either intensive on-site or off-site trainings – and I think clinical teams will find treating all stages of advanced cervical cancer considerably less complex than it may have seemed before.

 Advanced Gynecological Applicator Venezia™ is CE-approved and available for sales in the USA, but is not available in all markets.

References

  1. Kirisits C, Lang S, Dimopoulos J et al. The Vienna applicator for combined intracavitary and interstitial brachytherapy of cervical cancer: design, application, treatment planning, and dosimetric results. Int J Radiat Oncol Biol Phys 2006; 65: 624-630.
  2. Hannoun-Levi J-M, Chand-Fouche M-E, Gautier M et al. Interstitial preoperative high-dose-rate brachytherapy for early stage cervical cancer: dose-volume histogram parameters, pathologic response and early clinical outcome. Brachytherapy 2013; 12: 48-155.
  3. Bailleux C, Falk Tuan, A, Chande-Fouche M-E, et al. Concomitant cervical and transperineal parametrial high-dose-rate brachytherapy boost for locally advanced cervical cancer. J Contemp Brachytherapy. 2016 Feb;8(1): 23-31. doi: 10.5114/jcb.2016.57535. Epub 2016 Jan 28.

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