Adding Ipsilateral V{sub 20} and V{sub 30} to Conventional Dosimetric Constraints Predicts Radiation Pneumonitis in Stage IIIA-B NSCLC Treated With Combined-Modality Therapy

Journal Article · Fri Jan 15 04:00:00 EST 2010 · International Journal of Radiation Oncology, Biology and Physics

DOI:https://doi.org/10.1016/j.ijrobp.2009.01.036· OSTI ID:21367593

Ramella, Sara ^[1]; Trodella, Lucio ^[1]; Mineo, Tommaso Claudio; Pompeo, Eugenio ^[2]; Stimato, Gerardina; Gaudino, Diego ^[1]; Valentini, Vincenzo ^[3]; Cellini, Francesco; Ciresa, Marzia; Fiore, Michele ^[1]; Piermattei, Angelo ^[4]; Russo, Patrizia ^[5]; Cesario, Alfredo ^[6]; D'Angelillo, Rolando M ^[1]

---

1. Radiotherapy Unit, Campus Bio-Medico University, Rome (Italy)
2. Department of Thoracic Surgery, Tor Vergata University, Rome (Italy)
3. Department of Radiation Therapy, Catholic University, Rome (Italy)
4. Department of Physics, Catholic University, Rome (Italy)
5. Lung Cancer Unit, National Cancer Research Institute, Genoa (Italy)
6. Clinical CdC San Raffaele, Velletri (Italy)

Purpose: To determine lung dosimetric constraints that correlate with radiation pneumonitis in non-small-cell lung cancer patients treated with three-dimensional radiation therapy and concurrent chemotherapy. Methods and Materials: Between June 2002 and December 2006, 97 patients with locally advanced non-small-cell lung cancer were treated with concomitant radiochemotherapy. All patients underwent complete three-dimensional treatment planning (including dose-volume histograms), and patients were treated only if the percentage of total lung volume exceeding 20 Gy (V{sub 20}) and 30 Gy (V{sub 30}), and mean lung dose (MLD) had not exceeded the constraints of 31%, 18%, and 20 Gy, respectively. The total and ipsilateral lung dose-volume histogram parameters, planning target volume, and total dose delivered were analyzed and correlated with pneumonitis incidence. Results: If dose constraints to the total lung were respected, the most statistically significant factors predicting pneumonitis were the percentage of ipsilateral lung volume exceeding 20 Gy (V{sub 20}ipsi), percentage of ipsilateral lung volume exceeding 30 Gy (V{sub 30}ipsi), and planning target volume. These parameters divided the patients into low- and high-risk groups: if V{sub 20}ipsi was 52% or lower, the risk of pneumonitis was 9%, and if V{sub 20}ipsi was greater than 52%, the risk of pneumonitis was 46%; if V{sub 30}ipsi was 39% or lower, the risk of pneumonitis was 8%, and if V{sub 30}ipsi was greater than 39%, the risk of pneumonitis was 38%. Actuarial curves of the development of pneumonitis of Grade 2 or higher stratified by V{sub 20}ipsi and V{sub 30}ipsi were created. Conclusions: The correlation between pneumonitis and dosimetric constraints has been validated. Adding V{sub 20}ipsi and V{sub 30}ipsi to the classical total lung constraints could reduce pulmonary toxicity in concurrent chemoradiation treatment. V{sub 20}ipsi and V{sub 30}ipsi are important if the V{sub 20} to the total lung, V{sub 30} to the total lung, and mean lung dose have not exceeded the constraints of 31%, 18%, and 20 Gy, respectively.

• OSTI ID: 21367593
• Journal Information: International Journal of Radiation Oncology, Biology and Physics, Journal Name: International Journal of Radiation Oncology, Biology and Physics Journal Issue: 1 Vol. 76; ISSN IOBPD3; ISSN 0360-3016
• Country of Publication: United States
• Language: English

Related Subjects

62 RADIOLOGY AND NUCLEAR MEDICINE
BODY
CHEMOTHERAPY
CORRELATIONS
DISEASES
DOSES
LUNGS
MEDICINE
NEOPLASMS
NUCLEAR MEDICINE
ORGANS
PNEUMONITIS
RADIATION DOSES
RADIOLOGY
RADIOTHERAPY
RESPIRATORY SYSTEM
THERAPY
THREE-DIMENSIONAL CALCULATIONS