To operate or to radiate: The added value of the maximal standardized uptake value in PET-FDG in cervical cancer patients

Cervical cancer is one of the leading causes of death among women with gynecological malignancies. In early stages of the disease (IB-IIA), surgical treatment alone is usually the treatment of choice. However, some high-risk patients are referred for postoperative chemo-radiotherapy, leading to increased morbidity. Maximal Standardized Uptake Value (SUV_max) is a positron emission tomography-computed tomography (PET-CT)-derived semiquantitative measurement of fluorodeoxyglucose (FDG) uptake in a defined lesion and may reflect tumor aggressiveness. The purpose of this study was to determine whether preoperative high SUV_max values can be used for the selection of initial therapy, thus reducing the side effects resulting from bimodal treatment. PET-CT studies of 46 cervical cancer patients who underwent surgery were reviewed, and SUV_max data were collected. Statistical analyses were performed to determine the relationships between SUV_max values and clinical parameters, modalities of treatment, and outcomes. SUV _max was found to correlate with depth of tumor invasion (r = 0.46, p < 0.003). A statistically significant correlation was also found between SUV_max and histological grade, with the mean and variance of SUV _max significantly lower for grade one, as compared to grades two and three (mean 1.10, 11.06, and 8.88; variance 3.57, 45.60, and 29.79, respectively; p < 0.0001 and p = 0.076). A possible SUV_max cutoff value of 10.08 was identified as a potential indicator of increased risk for receiving bimodal treatment, with a sensitivity of 61.5 % and a specificity of 75.8 %. SUV_max can be used for differentiating early-stage cervical cancer patients who will need postoperative adjuvant treatment and therefore can serve as an additional modality to reduce the need for bimodal therapy in these patients.