Pretreatment F-18 FDG-PET/CT scans may predict relapse in patients with advanced high-grade serous ovarian cancer, according to a research team in Spain.
Given that relapse and mortality rates are high in these patients, the finding suggests that the technique could help clinicians choose initial treatment strategies, noted lead author Daniela Travaglio Morales, MD, of La Paz University Hospital in Madrid, and colleagues.
“It is necessary to identify patients at high risk of relapse and to investigate different maintenance treatments to reduce recurrence,” the group wrote. The study was published February 19 in Cancers.
High-grade serous ovarian carcinoma (HGSOC) is an aggressive subtype of epithelial ovarian cancer with poor outcomes. Up to 80% of women with the disease who respond to first-line chemotherapy relapse within 18 months, the authors explained.
While many studies have investigated the prognostic value of PET/CT parameters such as metabolic tumor volume (MTV) and total lesion glycolysis (TLG) after initial treatment, so far, only a few studies have investigated the value of these parameters in patients before initial treatment, the group noted. To explore the additional value of the technique, the researchers thus analyzed the relationship between MTV and TLG on pretreatment F-18 FDG-PET/CT and clinical outcomes.
The group analyzed data from 47 patients diagnosed with advanced HGSOC who underwent pretreatment scans at their center between 2012 and 2020. Two experienced nuclear medicine physicians evaluated the images and calculated total lesion glycolysis and metabolic tumor volume parameters in regions of interest based on tumor uptake of F-18 FDG radiotracer. The group then performed a univariate and survival-curves analysis to determine correlations between the parameters and survival outcomes among the patients.
An example of two different patients with high and low tumor burden. (A) A 54-year-old patient with HGSOC; MTVtotal: 1,204 cm3, MTVtarget: 1,186 cm3, TLGtarget: 3768.6 mL × cm3, and TLGtotal: 3777.4 mL × cm3. DFS= 4 months. (B) A 50-year-old patient with HGSOC; MTVtotal: 194.8 cm3, MTVtarget: 152 cm3, TLGtarget: 542.6 mL × cm3, and TLGtotal: 261.2 mL × cm3. DFS = 44.9 months. Image and caption available for republishing under Creative Commons license (CC BY 4.0 DEED, Attribution 4.0 International) and courtesy of Cancers.
According to the results, the median disease-free survival (DFS) was 18 months, and overall survival was 33.6 months, and MTV was significantly associated with DFS. Specifically, patients with an MTVtotal greater than 427.8 cm3 and an MTVtarget greater than 434 cm3 on the images had shorter DFS than patients with lower values (18.8 vs. 31 months and 15.6 vs. 30 months).
In addition, patients with higher TLGtotal and TLG(t) values on F-18 FDG-PET/CT also tended to have worse DFS and MTVtotal was statistically significantly associated with DFS, the group reported.
“We found that MTV and TLG have a significant correlation with disease recurrence: patients with high tumor burden measured by MTV and TLG have a higher risk of relapse, with MTV being the strongest predictor,” the group wrote.
Ultimately, to date, all the published data concerning PET/CT metabolic parameters in patients with ovarian cancer have been retrospective studies with small numbers of patients, including the present study, and thus further prospective studies with a wider sample of patients are needed, the authors wrote.
“The variation of the metabolic parameters between pre- and post-treatment F-18 FDG-PET/CT, their prognostic value, and their impact on the assessment of the primary treatment would be very interesting fields of research for future studies,” the group concluded.
The full study is available here.