Predictive value of 18F-FDG PET/CT in restaging patients affected by ovarian carcinoma: a multicentre study
Ovarian cancer is the eighth most common malignancy among women and has a high mortality rate. Prognostic factors able to drive an effective therapy are essential. 18F-Fluoro-2-deoxyglucose positron emission tomography/computed tomography (18F-FDG PET/CT) has been investigated in patients with epithelial ovarian cancer and showed promise in diagnosing, staging, detecting recurrent lesions and monitoring treatment response. Conversely, its prognostic role remains unclear. We aimed at assessing the prognostic value of 18F-FDG PET/CT performed in the restaging process in a multicentre study.
We evaluated 168 patients affected by ovarian carcinoma, who underwent a restaging 18F-FDG PET/CT. The presence of local recurrences, lymph node involvement and distant metastasis was recorded as well as lesion dimensions, maximum and mean standardized uptake values (SUVmax and SUVmean, respectively). Progression-free survival (PFS) and overall survival (OS) at 3 and 4 years were computed by using Kaplan-Meier curves. Increased odds ratio was assessed using Cox regression analysis testing all lesion parameters measured by PET/CT.
PFS was significantly longer in patients with a negative than a positive restaging PET/CT study (3- and 4-year PFS 64 and 53 % vs 23 and 12 %, respectively; p < 0.001). Similarly, a negative study was associated with a significantly higher OS rate after 4 years of follow-up (67 vs 25 % in negative and positive groups, respectively; p < 0.001). Lymph node or distant involvement were also independently associated with an increased risk of disease progression [hazard ratio (HR) 1.6 and 2.2, respectively; p = 0.003]. Moreover, PET/CT showed an incremental prognostic value compared to the International Federation of Gynecology and Obstetrics (FIGO) staging system. In the analysis of patient subsets, individuals with the same FIGO stage I–II but with negative PET had a significantly better 4-year OS than patients with low FIGO stage but positive PET. This implies that patients with the same FIGO stage can be further prognostically stratified using PET (p = 0.01). At receiver-operating characteristic (ROC) analysis, no thresholds for semiquantitative parameters were predictive of a worse outcome.
18F-FDG PET/CT has an important prognostic value in assessing the risk of disease progression and mortality rate. An efficacious therapy planning might therefore effectively rely on 18F-FDG PET/CT findings. Semiquantitative data were not proven to be an effective tool to predict disease progression.
KeywordsOvarian carcinoma 18F-FDG PET/CT Prognostic value FIGO staging system Restaging
We would like to thank all the institutions and their co-workers who actively participated in our multicentre study for their invaluable help. We also thank Dr. James T. Thackeray for language editing and thorough revision of the manuscript.
Compliance with ethical standards
Conflicts of interest
The authors disclose that they did not receive any personal or financial support for this multicentre study.
All procedures performed in studies involving human participants were in accordance with the ethical standards of the institutional and/or national research committee and with the 1964 Declaration of Helsinki and its later amendments or comparable ethical standards. For this type of study formal consent is not required.
Informed consent was obtained from all individual participants included in the study.
- 6.Konishi H, Takehara K, Kojima A, Okame S, Yamamoto Y, Shiroyama Y, et al. Maximum standardized uptake value of fluorodeoxyglucose positron emission tomography/computed tomography is a prognostic factor in ovarian clear cell adenocarcinoma. Int J Gynecol Cancer 2014;24:1190–4.PubMedCrossRefGoogle Scholar
- 15.Schwarz JK, Grigsby PW, Dehdashti F, Delbeke D. The role of 18F-FDG PET in assessing therapy response in cancer of the cervix and ovaries. J Nucl Med 2009;50 Suppl 1:64S–73.Google Scholar
- 20.Boers-Sonderen MJ, de Geus-Oei LF, Desar IM, van der Graaf WT, Oyen WJ, Ottevanger PB, et al. Temsirolimus and pegylated liposomal doxorubicin (PLD) combination therapy in breast, endometrial, and ovarian cancer: phase Ib results and prediction of clinical outcome with FDG-PET/CT. Target Oncol 2014;9:339–47.PubMedCrossRefGoogle Scholar
- 23.Tsuyoshi H, Morishita F, Orisaka M, Okazawa H, Yoshida Y. 18F-fluorothymidine PET is a potential predictive imaging biomarker of the response to gemcitabine-based chemotherapeutic treatment for recurrent ovarian cancer: preliminary results in three patients. Clin Nucl Med 2013;38:560–3.PubMedCrossRefGoogle Scholar
- 24.Risum S, Høgdall C, Markova E, Berthelsen AK, Loft A, Jensen F, et al. Influence of 2-(18F) fluoro-2-deoxy-D-glucose positron emission tomography/computed tomography on recurrent ovarian cancer diagnosis and on selection of patients for secondary cytoreductive surgery. Int J Gynecol Cancer 2009;19:600–4.PubMedCrossRefGoogle Scholar
- 27.Kosary CL. FIGO stage, histology, histologic grade, age and race as prognostic factors in determining survival for cancers of the female gynecological system: an analysis of 1973–87 SEER cases of cancers of the endometrium, cervix, ovary, vulva, and vagina. Semin Surg Oncol 1994;10:31–46.PubMedCrossRefGoogle Scholar