Artifacts in conventional computed tomography (CT) and free breathing four-dimensional CT induce uncertainty in gross tumor volume determination

Gitte Fredberg Persson, Ditte Eklund Nygaard, Per Munck af Rosenschöld, Ivan Richter Vogelius, Mirjana Josipovic, Lena Specht, Stine Korreman

    Publikation: Bidrag til tidsskriftTidsskriftartikelForskningpeer review

    Resumé

    Purpose
    Artifacts impacting the imaged tumor volume can be seen in conventional three-dimensional CT (3DCT) scans for planning of lung cancer radiotherapy but can be reduced with the use of respiration-correlated imaging, i.e., 4DCT or breathhold CT (BHCT) scans. The aim of this study was to compare delineated gross tumor volume (GTV) sizes in 3DCT, 4DCT, and BHCT scans of patients with lung tumors.

    Methods and Materials
    A total of 36 patients with 46 tumors referred for stereotactic radiotherapy of lung tumors were included. All patients underwent positron emission tomography (PET)/CT, 4DCT, and BHCT scans. GTVs in all CT scans of individual patients were delineated during one session by a single physician to minimize systematic delineation uncertainty. The GTV size from the BHCT was considered the closest to true tumor volume and was chosen as the reference. The reference GTV size was compared to GTV sizes in 3DCT, at midventilation (MidV), at end-inspiration (Insp), and at end-expiration (Exp) bins from the 4DCT scan.

    Results
    The median BHCT GTV size was 4.9 cm3 (0.1–53.3 cm3). Median deviation between 3DCT and BHCT GTV size was 0.3 cm3 (−3.3 to 30.0 cm3), between MidV and BHCT size was 0.2 cm3 (−5.7 to 19.7 cm3), between Insp and BHCT size was 0.3 cm3 (−4.7 to 24.8 cm3), and between Exp and BHCT size was 0.3 cm3 (−4.8 to 25.5 cm3). The 3DCT, MidV, Insp, and Exp median GTV sizes were all significantly larger than the BHCT median GTV size.

    Conclusions
    In the present study, the choice of CT method significantly influenced the delineated GTV size, on average, leading to an increase in GTV size compared to the reference BHCT. The uncertainty caused by artifacts is estimated to be in the same magnitude as delineation uncertainty and should be considered in the design of margins for radiotherapy.
    OriginalsprogEngelsk
    TidsskriftInternational Journal of Radiation Oncology, Biology, Physics
    Vol/bind80
    Udgave nummer5
    Sider (fra-til)1573-1580
    ISSN0360-3016
    DOI
    StatusUdgivet - 2011

    Citer dette

    Persson, Gitte Fredberg ; Nygaard, Ditte Eklund ; Munck af Rosenschöld, Per ; Vogelius, Ivan Richter ; Josipovic, Mirjana ; Specht, Lena ; Korreman, Stine. / Artifacts in conventional computed tomography (CT) and free breathing four-dimensional CT induce uncertainty in gross tumor volume determination. I: International Journal of Radiation Oncology, Biology, Physics. 2011 ; Bind 80, Nr. 5. s. 1573-1580.
    @article{f4aa7c20f3044e57bc5594e1b489ef72,
    title = "Artifacts in conventional computed tomography (CT) and free breathing four-dimensional CT induce uncertainty in gross tumor volume determination",
    abstract = "Purpose Artifacts impacting the imaged tumor volume can be seen in conventional three-dimensional CT (3DCT) scans for planning of lung cancer radiotherapy but can be reduced with the use of respiration-correlated imaging, i.e., 4DCT or breathhold CT (BHCT) scans. The aim of this study was to compare delineated gross tumor volume (GTV) sizes in 3DCT, 4DCT, and BHCT scans of patients with lung tumors. Methods and Materials A total of 36 patients with 46 tumors referred for stereotactic radiotherapy of lung tumors were included. All patients underwent positron emission tomography (PET)/CT, 4DCT, and BHCT scans. GTVs in all CT scans of individual patients were delineated during one session by a single physician to minimize systematic delineation uncertainty. The GTV size from the BHCT was considered the closest to true tumor volume and was chosen as the reference. The reference GTV size was compared to GTV sizes in 3DCT, at midventilation (MidV), at end-inspiration (Insp), and at end-expiration (Exp) bins from the 4DCT scan. Results The median BHCT GTV size was 4.9 cm3 (0.1–53.3 cm3). Median deviation between 3DCT and BHCT GTV size was 0.3 cm3 (−3.3 to 30.0 cm3), between MidV and BHCT size was 0.2 cm3 (−5.7 to 19.7 cm3), between Insp and BHCT size was 0.3 cm3 (−4.7 to 24.8 cm3), and between Exp and BHCT size was 0.3 cm3 (−4.8 to 25.5 cm3). The 3DCT, MidV, Insp, and Exp median GTV sizes were all significantly larger than the BHCT median GTV size. Conclusions In the present study, the choice of CT method significantly influenced the delineated GTV size, on average, leading to an increase in GTV size compared to the reference BHCT. The uncertainty caused by artifacts is estimated to be in the same magnitude as delineation uncertainty and should be considered in the design of margins for radiotherapy.",
    keywords = "Lung cancer, Four-dimensional CT, Artifacts, Gross tumor volume, Breathhold CT",
    author = "Persson, {Gitte Fredberg} and Nygaard, {Ditte Eklund} and {Munck af Rosensch{\"o}ld}, Per and Vogelius, {Ivan Richter} and Mirjana Josipovic and Lena Specht and Stine Korreman",
    year = "2011",
    doi = "10.1016/j.ijrobp.2010.10.036",
    language = "English",
    volume = "80",
    pages = "1573--1580",
    journal = "International Journal of Radiation Oncology, Biology, Physics",
    issn = "0360-3016",
    publisher = "Elsevier Inc.",
    number = "5",

    }

    Artifacts in conventional computed tomography (CT) and free breathing four-dimensional CT induce uncertainty in gross tumor volume determination. / Persson, Gitte Fredberg; Nygaard, Ditte Eklund; Munck af Rosenschöld, Per; Vogelius, Ivan Richter; Josipovic, Mirjana; Specht, Lena; Korreman, Stine.

    I: International Journal of Radiation Oncology, Biology, Physics, Bind 80, Nr. 5, 2011, s. 1573-1580.

    Publikation: Bidrag til tidsskriftTidsskriftartikelForskningpeer review

    TY - JOUR

    T1 - Artifacts in conventional computed tomography (CT) and free breathing four-dimensional CT induce uncertainty in gross tumor volume determination

    AU - Persson, Gitte Fredberg

    AU - Nygaard, Ditte Eklund

    AU - Munck af Rosenschöld, Per

    AU - Vogelius, Ivan Richter

    AU - Josipovic, Mirjana

    AU - Specht, Lena

    AU - Korreman, Stine

    PY - 2011

    Y1 - 2011

    N2 - Purpose Artifacts impacting the imaged tumor volume can be seen in conventional three-dimensional CT (3DCT) scans for planning of lung cancer radiotherapy but can be reduced with the use of respiration-correlated imaging, i.e., 4DCT or breathhold CT (BHCT) scans. The aim of this study was to compare delineated gross tumor volume (GTV) sizes in 3DCT, 4DCT, and BHCT scans of patients with lung tumors. Methods and Materials A total of 36 patients with 46 tumors referred for stereotactic radiotherapy of lung tumors were included. All patients underwent positron emission tomography (PET)/CT, 4DCT, and BHCT scans. GTVs in all CT scans of individual patients were delineated during one session by a single physician to minimize systematic delineation uncertainty. The GTV size from the BHCT was considered the closest to true tumor volume and was chosen as the reference. The reference GTV size was compared to GTV sizes in 3DCT, at midventilation (MidV), at end-inspiration (Insp), and at end-expiration (Exp) bins from the 4DCT scan. Results The median BHCT GTV size was 4.9 cm3 (0.1–53.3 cm3). Median deviation between 3DCT and BHCT GTV size was 0.3 cm3 (−3.3 to 30.0 cm3), between MidV and BHCT size was 0.2 cm3 (−5.7 to 19.7 cm3), between Insp and BHCT size was 0.3 cm3 (−4.7 to 24.8 cm3), and between Exp and BHCT size was 0.3 cm3 (−4.8 to 25.5 cm3). The 3DCT, MidV, Insp, and Exp median GTV sizes were all significantly larger than the BHCT median GTV size. Conclusions In the present study, the choice of CT method significantly influenced the delineated GTV size, on average, leading to an increase in GTV size compared to the reference BHCT. The uncertainty caused by artifacts is estimated to be in the same magnitude as delineation uncertainty and should be considered in the design of margins for radiotherapy.

    AB - Purpose Artifacts impacting the imaged tumor volume can be seen in conventional three-dimensional CT (3DCT) scans for planning of lung cancer radiotherapy but can be reduced with the use of respiration-correlated imaging, i.e., 4DCT or breathhold CT (BHCT) scans. The aim of this study was to compare delineated gross tumor volume (GTV) sizes in 3DCT, 4DCT, and BHCT scans of patients with lung tumors. Methods and Materials A total of 36 patients with 46 tumors referred for stereotactic radiotherapy of lung tumors were included. All patients underwent positron emission tomography (PET)/CT, 4DCT, and BHCT scans. GTVs in all CT scans of individual patients were delineated during one session by a single physician to minimize systematic delineation uncertainty. The GTV size from the BHCT was considered the closest to true tumor volume and was chosen as the reference. The reference GTV size was compared to GTV sizes in 3DCT, at midventilation (MidV), at end-inspiration (Insp), and at end-expiration (Exp) bins from the 4DCT scan. Results The median BHCT GTV size was 4.9 cm3 (0.1–53.3 cm3). Median deviation between 3DCT and BHCT GTV size was 0.3 cm3 (−3.3 to 30.0 cm3), between MidV and BHCT size was 0.2 cm3 (−5.7 to 19.7 cm3), between Insp and BHCT size was 0.3 cm3 (−4.7 to 24.8 cm3), and between Exp and BHCT size was 0.3 cm3 (−4.8 to 25.5 cm3). The 3DCT, MidV, Insp, and Exp median GTV sizes were all significantly larger than the BHCT median GTV size. Conclusions In the present study, the choice of CT method significantly influenced the delineated GTV size, on average, leading to an increase in GTV size compared to the reference BHCT. The uncertainty caused by artifacts is estimated to be in the same magnitude as delineation uncertainty and should be considered in the design of margins for radiotherapy.

    KW - Lung cancer

    KW - Four-dimensional CT

    KW - Artifacts

    KW - Gross tumor volume

    KW - Breathhold CT

    U2 - 10.1016/j.ijrobp.2010.10.036

    DO - 10.1016/j.ijrobp.2010.10.036

    M3 - Journal article

    VL - 80

    SP - 1573

    EP - 1580

    JO - International Journal of Radiation Oncology, Biology, Physics

    JF - International Journal of Radiation Oncology, Biology, Physics

    SN - 0360-3016

    IS - 5

    ER -