Format

Send to

Choose Destination
Radiother Oncol. 2015 Jun;115(3):335-41. doi: 10.1016/j.radonc.2015.05.019. Epub 2015 Jun 23.

Impact of 4D-(18)FDG-PET/CT imaging on target volume delineation in SBRT patients with central versus peripheral lung tumors. Multi-reader comparative study.

Author information

1
Department of Radiation Oncology, University Medical Center Freiburg, Germany; German Cancer Consortium (DKTK), Heidelberg, Partner Site Freiburg, Germany.
2
Department of Radiation Oncology, University Medical Center Freiburg, Germany.
3
Department of Radiation Oncology, Massachusetts General Hospital, Boston, USA.
4
Department of Nuclear Medicine, University Medical Center Freiburg, Germany.
5
Department of Radiation Oncology, University Medical Center Freiburg, Germany; German Cancer Consortium (DKTK), Heidelberg, Partner Site Freiburg, Germany. Electronic address: ursula.nestle@uniklinik-freiburg.de.

Abstract

PURPOSE:

Evaluation of the effect of co-registered 4D-(18)FDG-PET/CT for SBRT target delineation in patients with central versus peripheral lung tumors.

METHODS:

Analysis of internal target volume (ITV) delineation of central and peripheral lung lesions in 21 SBRT-patients. Manual delineation was performed by 4 observers in 2 contouring phases: on respiratory gated 4DCT with diagnostic 3DPET available aside (CT-ITV) and on co-registered 4DPET/CT (PET/CT-ITV). Comparative analysis of volumes and inter-reader agreement.

RESULTS:

11 cases of peripheral and 10 central lesions were evaluated. In peripheral lesions, average CT-ITV was 6.2 cm(3) and PET/CT-ITV 8.6 cm(3), resembling a mean change in hypothetical radius of 2 mm. For both CT-ITVs and PET/CT-ITVs inter reader agreement was good and unchanged (0.733 and 0.716; p=0.58). All PET/CT-ITVs stayed within the PTVs derived from CT-ITVs. In central lesions, average CT-ITVs were 42.1 cm(3), PET/CT-ITVs 44.2 cm(3), without significant overall volume changes. Inter-reader agreement improved significantly (0.665 and 0.750; p<0.05). 2/10 PET/CT-ITVs exceeded the PTVs derived from CT-ITVs by >1 ml in average for all observers.

CONCLUSION:

The addition of co-registered 4DPET data to 4DCT based target volume delineation for SBRT of centrally located lung tumors increases the inter-observer agreement and may help to avoid geographic misses.

KEYWORDS:

4DPET/CT; Central lung tumors; SBRT; Target volume delineation

PMID:
26116339
DOI:
10.1016/j.radonc.2015.05.019
[Indexed for MEDLINE]

Supplemental Content

Full text links

Icon for Elsevier Science
Loading ...
Support Center