Beams Arrangement in Non-Small Cell Lung Cancer (NSCLC) According to PTV and Dosimetric Parameters Predictive of Pneumonitis

Ramella, Sara; Trodella, Lucio; Mineo, Tommaso Claudio; Pompeo, Eugenio; Gambacorta, Maria A.; Cellini, Francesco; Ciresa, Marzia; Fiore, Michele; Greco, Carlo; Gaudino, Diego; Stimato, Gerardina; Piermattei, Angelo; Cesario, Alfredo; D'Angelillo, Rolando M.

doi:10.1016/j.meddos.2009.05.003

« Previous Next »Medical Dosimetry
Volume 35, Issue 3 , Pages 169-178, Autumn 2010

Beams Arrangement in Non-Small Cell Lung Cancer (NSCLC) According to PTV and Dosimetric Parameters Predictive of Pneumonitis

Sara Ramella, M.D.
- Radiotherapy Unit, Campus Bio-Medico University, Rome, Italy
- Reprint requests to: Sara Ramella, M.D., Via E. Longoni 47, 00155, Rome, Italy
Lucio Trodella, M.D.
- Radiotherapy Unit, Campus Bio-Medico University, Rome, Italy
Tommaso Claudio Mineo, M.D.
- Department of Thoracic Surgery, Policlinico Tor Vergata University, Rome, Italy
Eugenio Pompeo, M.D.
- Department of Thoracic Surgery, Policlinico Tor Vergata University, Rome, Italy
Maria A. Gambacorta, M.D.
- Department of Radiation Therapy, Catholic University, Rome, Italy
Francesco Cellini, M.D.
- Radiotherapy Unit, Campus Bio-Medico University, Rome, Italy
Marzia Ciresa, M.D.
- Radiotherapy Unit, Campus Bio-Medico University, Rome, Italy
Michele Fiore, M.D.
- Radiotherapy Unit, Campus Bio-Medico University, Rome, Italy
Carlo Greco, M.D.
- Radiotherapy Unit, Campus Bio-Medico University, Rome, Italy
Diego Gaudino, Ph.D.
- Radiotherapy Unit, Campus Bio-Medico University, Rome, Italy
Gerardina Stimato, Ph.D.
- Radiotherapy Unit, Campus Bio-Medico University, Rome, Italy
Angelo Piermattei, Ph.D.
- Department of Physics, Catholic University, Rome, Italy
Alfredo Cesario, M.D.
- CdC San Raffaele, Velletri, Italy
- Department of Thoracic Surgery, Catholic University, Rome, Italy
Rolando M. D'Angelillo, M.D.
- Radiotherapy Unit, Campus Bio-Medico University, Rome, Italy

Received 5 September 2008; accepted 5 May 2009. published online 26 June 2009.

Abstract

The aim of this study is to propose and validate an original new class of solutions for three-dimensional conformal radiation therapy (3DCRT) treatment planning for non-small cell lung cancer (NSCLC) according to the different patterns of disease presentation (on the basis of tumor location and volume) and to explore beams arrangement (planar or no-planar solutions) to respect dose constraints to the lung parenchyma. Benchmarks matched to validate the new approach are interuser reproducibility and saving on planning time. Tumor location was explored and specific categories created according to the tumor volume and location. Therefore, by applying planar and no-planar 3D plans, we searched for an optimization of the beams arrangement for each category. Dose-volume histograms (DVHs) were analyzed and a plan comparison performed. Results were then validated (class solution planning confirmation) by applying the same strategy to another group of patients. This has been realized at two dose levels (50.4 and 59.4 Gy). Fifty-nine patients were enrolled in this dosimetric study. In the first 27 patients (“exploratory sample”) three main planning target volume location categories were identified according to the pattern of the disease presentation: (1) centrally located; (2) peripheral T and mediastinal N (P+N); and (3) superior sulcus. Original class solutions were proposed for each location category. On the next 32 patients (“validation sample”), the treatment planning started directly with the recommended approach. Mean V_20Gy value was 18.8% (SD ± 7.25); mean V_30Gy:12% (SD ± 4.05); and mean lung dose: 11.6Gy (SD ± 5.77). No differences between the two total dose level groups were observed. These results suggest a simple and reproducible tool for treatment planning in NSCLC, allowing interuser reproducibility and cutting down on planning time.

Key Words: Beams arrangement, Radiotherapy planning, NSCLC, Tumor volume