Patterns-of-failure guided biological target volume definition for head and neck cancer patients: FDG-PET and dosimetric analysis of dose escalation candidate subregions. Issue 2 (August 2017)

• Record Type: Journal Article
• Authors: Mohamed, Abdallah S.R.; Cardenas, Carlos E.; Garden, Adam S.; Awan, Musaddiq J.; Rock, Crosby D.; Westergaard, Sarah A.; Brandon Gunn, G.; Belal, Abdelaziz M.; El-Gowily, Ahmed G.; Lai, Stephen Y.; Rosenthal, David I.; Fuller, Clifton D.; Aristophanous, Michalis
• Is Part Of: Radiotherapy and oncology. Volume 124:Issue 2(2017:Aug.)
• Page Start: 248
• Page End: 255
• Publication Date: 2017-08
• Subjects: FDG-PET -- Patterns of failure -- Dose escalation -- Biological target volume -- Head and neck cancer; Oncology -- Periodicals; Radiotherapy -- Periodicals; Tumors -- Periodicals; Medical Oncology -- Periodicals; Neoplasms -- radiotherapy -- Periodicals; Radiotherapy -- Periodicals; Radiothérapie -- Périodiques; Cancérologie -- Périodiques; Tumeurs -- Périodiques; Electronic journals; 616.9940642
• DOI: 10.1016/j.radonc.2017.07.017
• Languages: English
• ISSNs: 0167-8140

Abstract

Abstract: Background: To identify the radio-resistant subvolumes in pretreatment FDG-PET by mapping the spatial location of the origin of tumor recurrence after IMRT for head-and-neck squamous cell cancer to the pretreatment FDG-PET/CT. Methods: Patients with local/regional recurrence after IMRT with available FDG-PET/CT and post-failure CT were included. For each patient, both pre-therapy PET/CT and recurrence CT were co-registered with the planning CT (pCT). A 4-mm radius was added to the centroid of mapped recurrence growth target volumes (rGTV's) to create recurrence nidus-volumes (NVs). The overlap between boost-tumor-volumes (BTV) representing different SUV thresholds/margins combinations and NVs was measured. Results: Forty-seven patients were eligible. Forty-two (89.4%) had type A central high dose failure. Twenty-six (48%) of type A rGTVs were at the primary site and 28 (52%) were at the nodal site. The mean dose of type A rGTVs was 71 Gy. BTV consisting of 50% of the maximum SUV plus 10 mm margin was the best subvolume for dose boosting due to high coverage of primary site NVs (92.3%), low average relative volume to CTV1 (41%), and least average percent voxels outside CTV1 (19%). Conclusions: The majority of loco-regional recurrences originate in the regions of central-high-dose. When correlated with pretreatment FDG-PET, the majority of recurrences originated in an area that would be covered by additional 10 mm margin on the volume of 50% of the maximum FDG uptake.