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Sinonasal malignancies and charged particle radiation treatment: a systematic literature review.

Cianchetti M, Amichetti M - Int J Otolaryngol (2012)

Bottom Line: We found six studies with data on clinical outcome.Conclusion.Promising results achieved so far must be confirmed in further studies.

View Article: PubMed Central - PubMed

Affiliation: Agenzia Provinciale per la Protonterapia Trento (ATrep), Via Fratelli Perini, 181, 38122 Trento, Italy.

ABSTRACT
Background. Paranasal and nasal cavity malignancies are rare tumors that frequently present at advanced stages. Tumor extension and anatomic complexity pose a challenge for their treatment. Due to their peculiar physical and biological properties particle radiation therapy, i.e. protons and ions can have a role in their management. We performed a systematic literature review to gather clinical evidence about their use to treat sinonasal malignancies. Materials and Methods. We searched the browsers PubMed and Medline as well as specific journals and conference proceedings. Inclusion criteria were: at least 10 patients, English language, reporting outcome and/or toxicity data. Results. We found six studies with data on clinical outcome. Carbon and helium ions were each used in one study, protons in four. Toxicity was specifically described in five studies. One reported acute toxicity of carbon ions, one dealt with brain toxicity from both carbon ions and protons. Three papers reported on visual toxicity: one from carbon ions, one from protons and one from both. Specific data were extracted and compared with the most pertinent literature. Conclusion. Particle radiation therapy is in its early phase of development. Promising results achieved so far must be confirmed in further studies.

No MeSH data available.


Related in: MedlinePlus

Bragg peak and Spread-Out Bragg Peak (SOBP) for a proton beam in comparison with photon and electron dose distributions.
© Copyright Policy - open-access
Related In: Results  -  Collection


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fig1: Bragg peak and Spread-Out Bragg Peak (SOBP) for a proton beam in comparison with photon and electron dose distributions.

Mentions: Particle radiation therapy, that is, protons and heavy ions, is a relatively new type of radiation therapy that could enhance the therapeutic ratio for sinonasal malignancies. Protons and heavy ions share the same characteristic dose distribution, the so-called Bragg Peak, that is the release of almost all their energy in a few millimeters at the end of their path (see Figure 1). This peak is narrow and not suitable to treat target volumes so it has to be opportunely spread out, the so-called SOBP-Spread Out-Bragg Peak, allowing thus the delivery of high doses sparing at the same time OARs. Comparative treatment planning studies have demonstrated the robustness of heavy particle generated plans and showed their advantages over photon plans [25]. Protons have a relative biologic effectiveness (RBE) that is slightly higher than photons according to some authors [26], its value being around 1.1, or exactly the same as photons according to others [27]. Anyhow, the International Commission on Radiation Units and Measurements (ICRU) in its 78 report issued in 2007 recommends using a value of 1.1 [28]. More complex is the situation for heavy charged particles since the RBE is not constant along their path, but increases with increasing depth, reaching the maximum at the peak region [29]. RBE is dependent indeed by the microdosimetric pattern of energy deposition that is, the Linear Energy Transfer (LET) that increases as they slow down [30]. The advantage of high LET radiations is that there is less variation in radiosensitivity during the cell cycle, less reduction of repair of radiation injury, and lower oxygen enhancement ratio [31]. From preparatory studies, an RBE value of 3 for carbon ion was found at the distal part of the SOPB [32]. In order of taking into account the different RBE of particle radiation therapy, their dose is expressed in Gy (RBE) that is the product of the physical dose in Gy multiplied for the specific RBE [30].


Sinonasal malignancies and charged particle radiation treatment: a systematic literature review.

Cianchetti M, Amichetti M - Int J Otolaryngol (2012)

Bragg peak and Spread-Out Bragg Peak (SOBP) for a proton beam in comparison with photon and electron dose distributions.
© Copyright Policy - open-access
Related In: Results  -  Collection

Show All Figures
getmorefigures.php?uid=PMC3368195&req=5

fig1: Bragg peak and Spread-Out Bragg Peak (SOBP) for a proton beam in comparison with photon and electron dose distributions.
Mentions: Particle radiation therapy, that is, protons and heavy ions, is a relatively new type of radiation therapy that could enhance the therapeutic ratio for sinonasal malignancies. Protons and heavy ions share the same characteristic dose distribution, the so-called Bragg Peak, that is the release of almost all their energy in a few millimeters at the end of their path (see Figure 1). This peak is narrow and not suitable to treat target volumes so it has to be opportunely spread out, the so-called SOBP-Spread Out-Bragg Peak, allowing thus the delivery of high doses sparing at the same time OARs. Comparative treatment planning studies have demonstrated the robustness of heavy particle generated plans and showed their advantages over photon plans [25]. Protons have a relative biologic effectiveness (RBE) that is slightly higher than photons according to some authors [26], its value being around 1.1, or exactly the same as photons according to others [27]. Anyhow, the International Commission on Radiation Units and Measurements (ICRU) in its 78 report issued in 2007 recommends using a value of 1.1 [28]. More complex is the situation for heavy charged particles since the RBE is not constant along their path, but increases with increasing depth, reaching the maximum at the peak region [29]. RBE is dependent indeed by the microdosimetric pattern of energy deposition that is, the Linear Energy Transfer (LET) that increases as they slow down [30]. The advantage of high LET radiations is that there is less variation in radiosensitivity during the cell cycle, less reduction of repair of radiation injury, and lower oxygen enhancement ratio [31]. From preparatory studies, an RBE value of 3 for carbon ion was found at the distal part of the SOPB [32]. In order of taking into account the different RBE of particle radiation therapy, their dose is expressed in Gy (RBE) that is the product of the physical dose in Gy multiplied for the specific RBE [30].

Bottom Line: We found six studies with data on clinical outcome.Conclusion.Promising results achieved so far must be confirmed in further studies.

View Article: PubMed Central - PubMed

Affiliation: Agenzia Provinciale per la Protonterapia Trento (ATrep), Via Fratelli Perini, 181, 38122 Trento, Italy.

ABSTRACT
Background. Paranasal and nasal cavity malignancies are rare tumors that frequently present at advanced stages. Tumor extension and anatomic complexity pose a challenge for their treatment. Due to their peculiar physical and biological properties particle radiation therapy, i.e. protons and ions can have a role in their management. We performed a systematic literature review to gather clinical evidence about their use to treat sinonasal malignancies. Materials and Methods. We searched the browsers PubMed and Medline as well as specific journals and conference proceedings. Inclusion criteria were: at least 10 patients, English language, reporting outcome and/or toxicity data. Results. We found six studies with data on clinical outcome. Carbon and helium ions were each used in one study, protons in four. Toxicity was specifically described in five studies. One reported acute toxicity of carbon ions, one dealt with brain toxicity from both carbon ions and protons. Three papers reported on visual toxicity: one from carbon ions, one from protons and one from both. Specific data were extracted and compared with the most pertinent literature. Conclusion. Particle radiation therapy is in its early phase of development. Promising results achieved so far must be confirmed in further studies.

No MeSH data available.


Related in: MedlinePlus