Using a reduced spot size for intensity-modulated proton therapy potentially improves salivary gland-sparing in oropharyngeal cancer

التفاصيل البيبلوغرافية
العنوان: Using a reduced spot size for intensity-modulated proton therapy potentially improves salivary gland-sparing in oropharyngeal cancer
المؤلفون: Eugen B. Hug, Tara A. van de Water, C. Schilstra, Hendrik P. Bijl, Antony J. Lomax, Johannes A. Langendijk
المصدر: International journal of radiation oncology, biology, physics. 82(2)
سنة النشر: 2010
مصطلحات موضوعية: Organs at Risk, Cancer Research, medicine.medical_treatment, Submandibular Gland, Xerostomia, Salivary Glands, Sublingual Gland, stomatognathic system, Carcinoma, medicine, Proton Therapy, Humans, Parotid Gland, Radiology, Nuclear Medicine and imaging, Radiation treatment planning, Radiation Injuries, Proton therapy, Probability, Mouth, Radiation, Soft palate, Salivary gland, business.industry, Cancer, Radiotherapy Dosage, medicine.disease, Submandibular gland, Radiation therapy, stomatognathic diseases, Oropharyngeal Neoplasms, medicine.anatomical_structure, Oncology, Carcinoma, Squamous Cell, Radiotherapy, Intensity-Modulated, Palate, Soft, business, Nuclear medicine, Organ Sparing Treatments
الوصف: Purpose To investigate whether intensity-modulated proton therapy with a reduced spot size (rsIMPT) could further reduce the parotid and submandibular gland dose compared with previously calculated IMPT plans with a larger spot size. In addition, it was investigated whether the obtained dose reductions would theoretically translate into a reduction of normal tissue complication probabilities (NTCPs). Methods Ten patients with N0 oropharyngeal cancer were included in a comparative treatment planning study. Both IMPT plans delivered simultaneously 70 Gy to the boost planning target volume (PTV) and 54 Gy to the elective nodal PTV. IMPT and rsIMPT used identical three-field beam arrangements. In the IMPT plans, the parotid and submandibular salivary glands were spared as much as possible. rsIMPT plans used identical dose–volume objectives for the parotid glands as those used by the IMPT plans, whereas the objectives for the submandibular glands were tightened further. NTCPs were calculated for salivary dysfunction and xerostomia. Results Target coverage was similar for both IMPT techniques, whereas rsIMPT clearly improved target conformity. The mean doses in the parotid glands and submandibular glands were significantly lower for three-field rsIMPT (14.7 Gy and 46.9 Gy, respectively) than for three-field IMPT (16.8 Gy and 54.6 Gy, respectively). Hence, rsIMPT significantly reduced the NTCP of patient-rated xerostomia and parotid and contralateral submandibular salivary flow dysfunction (27%, 17%, and 43% respectively) compared with IMPT (39%, 20%, and 79%, respectively). In addition, mean dose values in the sublingual glands, the soft palate and oral cavity were also decreased. Obtained dose and NTCP reductions varied per patient. Conclusions rsIMPT improved sparing of the salivary glands and reduced NTCP for xerostomia and parotid and submandibular salivary dysfunction, while maintaining similar target coverage results. It is expected that rsIMPT improves quality of life during and after radiotherapy treatment.
تدمد: 1879-355X
URL الوصول: https://explore.openaire.eu/search/publication?articleId=doi_dedup___::cd70783980225a8b355cf10c6a2eec7c
https://pubmed.ncbi.nlm.nih.gov/21708427
Rights: CLOSED
رقم الانضمام: edsair.doi.dedup.....cd70783980225a8b355cf10c6a2eec7c
قاعدة البيانات: OpenAIRE