Cervical cancer histology and tumor differentiation affect 18F-fluorodeoxyglucose uptake

This study aimed to evaluate the variation in cervical cancer glucose metabolism for different tumor histologies and levels of differentiation, as measured by the uptake of 18F-fluorodeoxyglucose (FDG) by positron emission tomography (PET).

The study population consisted of 240 patients with International Federation of Gynecology and Obstetrics stages Ib1 through IVb cervical cancer, who underwent a pretreatment FDG-PET. Tumor histology included 221 squamous cell (SC), 4 adenosquamous (AS), and 15 adenocarcinoma (AC) tumors. There were 14 well, 145 moderately, and 81 poorly differentiated tumors. The stage distribution was as follows: 70 stage I tumors (9 AC, 2 AS, and 59 SC), 102 stage II tumors (3 AC, 1 AS, and 98 SC), 64 stage III tumors (3 AC, 1 AS, and 60 SC), and 4 stage IV tumors (4 SC). From the FDG-PET, maximal standardized uptake value (SUVmax) was determined. The variation in SUVmax was analyzed for differences based on tumor histology and differentiation.

For all patients, the mean SUVmax was 11.62 (range, 2.50-50.39). The mean SUVmax by histology was as follows: SC, 11.91 (range, 2.50-50.39); AS, 8.85 (range, 6.53-11.26); and AC, 8.05 (range, 2.83-13.92). Squamous versus nonsquamous tumors demonstrated a significant difference in SUVmax (P=.0153). SUVmax and tumor volume were not found to be correlated (R2=0.013). The mean SUVmax was 8.58 for well-differentiated, 11.56 for moderately differentiated, and 12.23 for poorly differentiated tumors. The mean SUVmax was significantly different for well-differentiated versus poorly differentiated cervical tumors (P=.0474).

Cervical tumor FDG uptake varied by histology and differentiation. SC tumors demonstrated a significantly higher SUVmax compared with nonsquamous cell tumors, and poorly differentiated tumors also had a higher SUVmax.