Prospective imaging assessment of mortality risk after head-and-neck radiotherapy.
OBJECTIVE
The optimal roles for imaging-based biomarkers in the management of head-and-neck cancer remain undefined. Unresolved questions include whether functional or anatomic imaging might improve mortality risk assessment for this disease. We addressed these issues in a prospective institutional trial.


METHODS
Ninety-eight patients with locally advanced pharyngolaryngeal squamous cell cancer were enrolled. Each underwent pre- and post-chemoradiotherapy contrast-enhanced computed tomography (CT) and (18)F-fluorodeoxyglucose (FDG)-positron emission tomography (PET)/CT imaging. Imaging parameters were correlated with survival outcomes.


RESULTS
Low post-radiation primary tumor FDG avidity correlated with improved survival on multivariate analysis; so too did complete primary tumor response by CT alone. Although both imaging modalities lacked sensitivity, each had high specificity and negative predictive value for disease-specific mortality risk assessment. Kaplan-Meier estimates confirmed that both CT and FDG-PET/CT stratify patients into distinct high- and low-probability survivorship groups on the basis of primary tumor response to radiotherapy. Subset analyses demonstrated that the prognostic value for each imaging modality was primarily derived from patients at high risk for local treatment failure (human papillomavirus [HPV]-negative disease, nonoropharyngeal primary disease, or tobacco use).


CONCLUSIONS
CT alone and FDG-PET/CT are potentially useful tools in head-and-neck cancer-specific mortality risk assessment after radiotherapy, particularly for selective use in cases of high-risk HPV-unrelated disease. Focus should be placed on corroboration and refinement of patient selection for imaging-based biomarkers in future studies.
Moeller
Benjamin J
BJ
Department of Radiation Oncology, University of Texas MD Anderson Cancer Center, Houston, TX 77030, USA.
Rana
Vishal
V
Cannon
Blake A
BA
Williams
Michelle D
MD
Sturgis
Erich M
EM
Ginsberg
Lawrence E
LE
Macapinlac
Homer A
HA
Lee
J Jack
JJ
Ang
K Kian
KK
Chao
K S Clifford
KS
Chronowski
Gregory M
GM
Frank
Steven J
SJ
Morrison
William H
WH
Rosenthal
David I
DI
Weber
Randal S
RS
Garden
Adam S
AS
Lippman
Scott M
SM
Schwartz
David L
DL
D000328:Adult; D000368:Aged; D002294:Carcinoma, Squamous Cell / Q000000981:diagnostic imaging / Q000188:drug therapy / Q000401:mortality / Q000532:radiotherapy; D019583:Dose Fractionation, Radiation; D005260:Female; D019788:Fluorodeoxyglucose F18; D052162:Human papillomavirus 16 / Q000302:isolation & purification; D006801:Humans; D007822:Laryngeal Neoplasms / Q000000981:diagnostic imaging / Q000188:drug therapy / Q000401:mortality / Q000532:radiotherapy; D008297:Male; D008875:Middle Aged; D015999:Multivariate Analysis; D010610:Pharyngeal Neoplasms / Q000000981:diagnostic imaging / Q000188:drug therapy / Q000401:mortality / Q000532:radiotherapy; D049268:Positron-Emission Tomography / Q000379:methods*; D011446:Prospective Studies; D012372:ROC Curve; D019275:Radiopharmaceuticals; D050397:Radiotherapy, Intensity-Modulated; D018570:Risk Assessment; D012680:Sensitivity and Specificity; D014057:Tomography, X-Ray Computed / Q000379:methods*
D019275:Radiopharmaceuticals; D019788:Fluorodeoxyglucose F18