Clinical implementation of intensity modulated proton therapy for testicular seminoma
DOI:
https://doi.org/10.2340/1651-226X.2025.43848Keywords:
testicular seminoma, intensity-modulated proton therapy (IMPT), Stage IIa seminoma, Proton Therapy, secondary cancers, Pencil beam scanningAbstract
Background and purpose: We have previously shown that proton therapy results in considerable reduced doses to abdominal organs at risk (OAR) which likely reduces the patient’s risk of a second malignant tumor, which is vital for this young population with favourable prognosis. Here, we present dosimetric results after implementing intensity modulated proton therapy (IMPT) as a national standard for seminoma.
Patient/material and methods: Thirty patients with stage IIA and IIB (< 3 cm) seminoma were treated with five-field robustly multi-field optimised (MFO) proton therapy to 20–24 Gy (relative biological effectiveness [RBE]) to the dog-leg retroperitoneal volume followed by a boost of 10–16 Gy (RBE) to the nodal metastasis. Control CTs were performed routinely, and target coverage evaluated. A standard two cone-beam CT (CBCT) set-up strategy with four match structures was developed, enabling implementation of a standard adaptive scheme.
Results: The median clinical target volume (CTV-E) length in the craniocaudal direction was 26.9 cm, with a median volume of 551.4 cm3. Target coverage V95% = 100% for the nominal plan and V95% ≥ 98% for worst-case scenarios were fulfilled for all treatment plans and the 46 recalculated plans on control CTs. Kidney V17Gy was 0–6% and mean kidney dose 0–6 Gy across all plans. Bowel bag V15Gy was 194–698 cm3. All other OAR showed low doses.
Four patients had replans (1–2 per patient). The median time for our image guidance (IG) strategy was 14:07 min across all patients with two CBCTs.
Interpretation: We have established a robust setup for treatment planning, IG strategy, treatment delivery and adequate response to replanning. Therefore, we suggest considering IMPT for testicular seminoma whenever available.
Downloads
References
Simone CB, Kramer K, O’Meara WP, Bekelman JE, Belard A, McDonough J, et al. Predicted rates of secondary malignancies from proton versus photon radiation therapy for stage I seminoma. Int J Radiat Oncol Biol Phys. 2012;82(1):242–9. https://doi.org/10.1016/j.ijrobp.2010.11.021 DOI: https://doi.org/10.1016/j.ijrobp.2010.11.021
Pasalic D, Prajapati S, Ludmir EB, Tang C, Choi S, Kudchadker R, et al. Outcomes and toxicities of proton and photon radiation therapy for testicular seminoma. Int J Part Ther. 2020;7(2):11–20. https://doi.org/10.14338/IJPT-20-00018.1 DOI: https://doi.org/10.14338/IJPT-20-00018.1
Pierorazio PM, Cheaib JG, Tema G, Patel HD, Gupta M, Sharma R, et al. Performance characteristics of clinical staging modalities for early stage testicular germ cell tumors: a systematic review. J Urol. 2020;203(5):894–901. https://doi.org/10.1097/JU.0000000000000594 DOI: https://doi.org/10.1097/JU.0000000000000594
Bandak M, Lauritsen J, Johansen C, Kreiber M, Skøtt JW, Agerbaek M, et al. Sexual function in a nationwide cohort of 2,260 survivors of testicular cancer after 17 years of followup. J Urol. 2018;200(4):794–800. https://doi.org/10.1016/j.juro.2018.04.077 DOI: https://doi.org/10.1016/j.juro.2018.04.077
Lauritsen J, Bandak M, Kreiberg M, Skøtt JW, Wagner T, Rosenvilde JJ, et al. Long-term neurotoxicity and quality of life in testicular cancer survivors—a nationwide cohort study. J Cancer Surviv. 2021;15:509–17. https://doi.org/10.1007/s11764-020-00944-1 DOI: https://doi.org/10.1007/s11764-020-00944-1
Knap MM, Bentzen SM, Jens Overgaard J. Late neurological complications after irradiation of malignant tumors of the testis. Acta Oncol. 2007;46(4):497–503. https://doi.org/10.1080/02841860601052752 DOI: https://doi.org/10.1080/02841860601052752
Travis LB, Fosså SD, Schonfeld SJ, McMaster ML, Lynch CF, Storm H, et al. Second cancers among 40,576 testicular cancer patients: focus on long-term survivors. J Natl Cancer Inst. 2005;97(18):1354–65. https://doi.org/10.1093/jnci/dji278 DOI: https://doi.org/10.1093/jnci/dji278
Kier MG, Hansen MK, Lauritsen J, Mortensen MS, Bandak M, Agerbaek M, et al. Second malignant neoplasms and cause of death in patients with germ cell cancer. A Danish nationwide cohort study. JAMA Oncol. 2016;2(12):1624–7. https://doi.org/10.1001/jamaoncol.2016.3651 DOI: https://doi.org/10.1001/jamaoncol.2016.3651
Hoppe BS, Mamalui-Hunter M, Mendenhall NP, Li Z, Indelicato DJ. Improving the therapeutic ratio by using proton therapy in patients with stage I or II seminoma. Am J Clin Oncol. 2013;36(1):31–7. https://doi.org/10.1097/COC.0b013e3182354b9e DOI: https://doi.org/10.1097/COC.0b013e3182354b9e
Efstathiou JA, Paly JJ, Lu HM, Athar BS, Moteabbed M, Niemierko A, et al. Adjuvant radiation therapy for early stage seminoma: Proton versus photon planning comparison and modeling of second cancer risk. Radiother Oncol. 2012;103(1):12–7. https://doi.org/10.1016/j.radonc.2012.01.012 DOI: https://doi.org/10.1016/j.radonc.2012.01.012
Maxwell R, Chang Y, Paul C, Vaughn DJ, Christodouleas JP. Cancer control, toxicity, and secondary malignancy risks of proton radiation therapy for stage I-IIB testicular seminoma. Adv Radiat Oncol. 2023;8(1):101259. https://doi.org/10.1016/j.adro.2023.101259 DOI: https://doi.org/10.1016/j.adro.2023.101259
Pursley J, Remillard K, Depauw N, Lee G, Grassberger C, Paganetti H, et al. Radiation therapy for stage IIA/B seminoma: modeling secondary cancer risk for protons and VMAT versus 3D photons. Cancers. 2024;16(4):784. https://doi.org/10.3390/cancers16040784 DOI: https://doi.org/10.3390/cancers16040784
Rønde HS, Kronborg C, Høyer M, Hansen J, Bak ME, Agergaard SN, et al. Dose comparison of robustly optimized intensity modulated proton therapy (IMPT) vs IMRT and VMAT photon plans for testicular seminoma. Acta Oncol. 2023;62(10):1222–9. https://doi.org/10.1080/0284186X.2023.2254925 DOI: https://doi.org/10.1080/0284186X.2023.2254925
Dansk Testis Cancer Gruppe (DaTeCa). Testikelkræft – primær screening, udredning, behandling, opfølgning og senfølger [Internet]. 2023. Danish. [Cited date: May 8th 2025] Available from: https://ducg.dk/dateca-testiscancer/kliniske-retningslinjer
Gay HA, Barthold HJ, O’Meara E, Bosch WR, Naga IE, Al-Loza R, et al. Pelvic normal tissue contouring guidelines for radiation therapy: a radiation therapy oncology group consensus panel atlas. Int J Radiat Oncol Biol Phys. 2012;83(3):e353–62. https://doi.org/10.1016/j.ijrobp.2012.01.023 DOI: https://doi.org/10.1016/j.ijrobp.2012.01.023
Jabbour SK, Hashem SA, Bosch W, Kim TK, Finkelstein SE, Anderson, BM, et al. Upper abdominal normal organ contouring guidelines and atlas: a radiation therapy oncology group consensus. Pract Radiat Oncol. 2014;4(2):82–9. https://doi.org/10.1016/j.prro.2013.06.004 DOI: https://doi.org/10.1016/j.prro.2013.06.004
ICRP, 1977. Recommendations of the ICRP. ICRP Publication 26. Ann. ICRP 1(3):1-53. DOI: https://doi.org/10.1016/0146-6453(76)90009-9
Van der Kogel A, Joiner M. Basic clinical radiobiology. 4th ed. CRC Press, London; 2009, p 195–206; 263–70. DOI: https://doi.org/10.1201/b13224
Kavanagh BD, Pan CC, Dawson LA, Das SK, Li WA, Haken RKT, et al. Radiation dose-volume effects in the stomach and small bowel. Int J Radiat Oncol Biol Phys. 2010;76(3):101–7. https://doi.org/10.1016/j.ijrobp.2009.05.071 DOI: https://doi.org/10.1016/j.ijrobp.2009.05.071
Banerjee R, Chakraborty S, Nygren I, Sinha R. Small bowel dose parameters predicting grade ≥3 acute toxicity in rectal cancer patients treated with neoadjuvant chemoradiation: an independent validation study comparing peritoneal space versus small bowel loop contouring techniques. Int J Radiat Oncol Biol Phys. 2013;85(5):1225–31. https://doi.org/10.1016/j.ijrobp.2012.09.036 DOI: https://doi.org/10.1016/j.ijrobp.2012.09.036
Pugh TJ, Amos RA, Baptiste SJ, Choi S, Nguyen QN, Zhu XR, et al. Multi-field optimization intensity-modulated proton therapy (MFO-IMPT) for prostate cancer: robustness analysis through simulation of rotational and translational alignment errors. Med Dosim. 2013;38(3):344–50. DOI: https://doi.org/10.1016/j.meddos.2013.03.007
https://doi:10.1016/j.meddos.2013. 03.007
Additional Files
Published
How to Cite
Issue
Section
Categories
License
Copyright (c) 2025 Heidi S. Rønde, Jesper F. Kallehauge, Morten Høyer, Anne Birgitte Als, Mads Agerbæk, Jakob Lauritsen, Peter M. Petersen , Lars Dysager, Camilla J.S. Kronborg
This work is licensed under a Creative Commons Attribution 4.0 International License.
