The Impact of Positron Emission Tomography/Computed Tomography in Edge Delineation of Gross Tumor Volume for Head and Neck Cancers

Journal Article · Fri Jun 01 04:00:00 EDT 2007 · International Journal of Radiation Oncology, Biology and Physics

DOI:https://doi.org/10.1016/j.ijrobp.2006.12.029· OSTI ID:20951657

Ashamalla, Hani ^[1]; Guirgius, Adel ^[2]; Bieniek, Ewa ^[2]; Rafla, Sameer ^[2]; Evola, Alex ^[3]; Goswami, Ganesh ^[3]; Oldroyd, Randall ^[2]; Mokhtar, Bahaa ^[2]; Parikh, Kapila ^[2]

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1. Department of Radiation Oncology, New York Methodist Hospital, Weill Medical College of Cornell University, New York, NY (United States) and Leading Edge Radiation Oncology Services, Brooklyn, NY (United States)
2. Department of Radiation Oncology, New York Methodist Hospital, Weill Medical College of Cornell University, New York, NY (United States)
3. Leading Edge Radiation Oncology Services, Brooklyn, NY (United States)

Purpose: To study anatomic biologic contouring (ABC), using a previously described distinct halo, to unify volume contouring methods in treatment planning for head and neck cancers. Methods and Materials: Twenty-five patients with head and neck cancer at various sites were planned for radiation therapy using positron emission tomography/computed tomography (PET/CT). The ABC halo was used in all PET/CT scans to contour the gross tumor volume (GTV) edge. The CT-based GTV (GTV-CT) and PET/CT-based GTV (GTV-ABC) were contoured by two independent radiation oncologists. Results: The ABC halo was observed in all patients studied. The halo had a standard unit value of 2.19 {+-} 0.28. The mean halo thickness was 2.02 {+-} 0.21 mm. Significant volume modification ({>=}25%) was seen in 17 of 25 patients (68%) after implementation of GTV-ABC. Concordance among observers was increased with the use of the halo as a guide for GTV determination: 6 patients (24%) had a {<=}10% volume discrepancy with CT alone, compared with 22 (88%) with PET/CT (p < 0.001). Interobserver variability decreased from a mean GTV difference of 20.3 cm{sup 3} in CT-based planning to 7.2 cm{sup 3} in PET/CT-based planning (p < 0.001). Conclusions: Using the 'anatomic biologic halo' to contour GTV in PET/CT improves consistency among observers. The distinctive appearance of the described halo and its presence in all of the studied tumors make it attractive for GTV contouring in head and neck tumors. Additional studies are needed to confirm the correlation of the halo with presence of malignant cells.

• OSTI ID: 20951657
• Journal Information: International Journal of Radiation Oncology, Biology and Physics, Journal Name: International Journal of Radiation Oncology, Biology and Physics Journal Issue: 2 Vol. 68; ISSN IOBPD3; ISSN 0360-3016
• Country of Publication: United States
• Language: English

Related Subjects

62 RADIOLOGY AND NUCLEAR MEDICINE
COMPUTERIZED TOMOGRAPHY
HEAD
MEDICAL PERSONNEL
NECK
NEOPLASMS
PATIENTS
PLANNING
POSITRON COMPUTED TOMOGRAPHY
RADIOTHERAPY
THICKNESS