Do 18F-FDG PET/CT Parameters in Oropharyngeal and Oral Cavity Squamous Cell Carcinomas Indicate HPV Status?

Abstract

Objective To explore the relationship of PET/CT parameters with HPV status of oropharyngeal (OP) and oral cavity (OC) squamous cell carcinomas (SCC). Material and Methods We retrospectively reviewed 39 patients with OC and OP SCC who underwent staging 18F-FDG PET/CT. PET/CT parameters were measured for the primary tumor and the hottest involved node, including maximum, mean, peak standardized uptake values (SUV max, SUV mean, SUV peak), metabolic tumor volume (MTV), total lesion glycolysis (TLG), standardized added metabolic activity (SAM), normalized standardized added metabolic activity (N SAM). Patient characteristics compared between HPV positive (HPV+) and negative (HPV−) groups. ROC analysis was used to dichotomize PET/CT parameters into high and low. Logistic regression models predicting HPV status were fit for each PET/CT parameter. Results The HPV+ group was comprised of 18 patients all with OP SCC; the HPV− group consisted of 21 patients, 4 OP cancer patients and 17 OC cancer patients. The HPV+ group had a higher proportion of N2 stage (94% vs 43%; p<0.001). Nodal PET/CT parameters were higher in the HPV+ group (p<0.01), this difference was not present for the primary lesion. After adjusting for sex and age, the association of higher nodal SUV max (OR 9.67), SUV mean (OR 10.48), SUV peak (OR 9.67), MTV (OR 14.52), TLG (OR 11.84) and SAM, N SAM (OR 16.21) with HPV+ status remained statistically significant (p<0.05). Conclusion Nodal PET/CT parameters predict HPV status. High nodal FDG uptake should raise suspicion for positive HPV status in the evaluation of the primary lesion.

Is There a Role for PET/CT Parameters to Characterize Benign, Malignant, and Metastatic Parotid Tumors?

“…The most widely used parameter is maximum standardized uptake value (SUV max ). SUV max reflects the highest pixel in a volume of interest (VOI) [8, 9]. Metabolic tumor volume is another parameter that gained interest in recent years [8, 10].…”

“…SUV max reflects the highest pixel in a volume of interest (VOI) [8, 9]. Metabolic tumor volume is another parameter that gained interest in recent years [8, 10]. Metabolic tumor volume is the volume of visually positive FDG activity [8, 10].…”

“…Peak SUV is the local average of a 1-mL spherical VOI centered on the SUV max . Peak SUV may be less affected by image noise and is more reproducible than SUV max [8, 9, 11]. Total lesion glycolysis is the product of metabolic tumor volume and mean SUV, incorporating both tumor size and functionality [8, 12, 13].…”

“…All of these PET/CT parameters can be used as biomarkers that may have prognostic and diagnostic value [8], although each has limitations. Both SUV max and peak SUV are prone to partial volume effects, reducing the voxel value in small tumors and making the assessment of small tumors challenging [8, 14, 15].…”

“…Both SUV max and peak SUV are prone to partial volume effects, reducing the voxel value in small tumors and making the assessment of small tumors challenging [8, 14, 15]. Metabolic tumor volume is dependent on the method used to determine the VOI [8, 16], and mean SUV and total lesion glycolysis also depend on the measured volume. Increasing the VOI’s size for the same tumor will reduce the mean SUV and increase total lesion glycolysis.…”