The role of 18F-fluorodeoxyglucose positron emission tomography in gestational trophoblastic tumours: a pilot study
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We conducted a pilot trial to evaluate the value of 18F-fluorodeoxyglucose (18F-FDG) positron emission tomography (PET) in gestational trophoblastic tumours (GTTs).
Patients with placental site trophoblastic tumour (PSTT), high-risk GTT (World Health Organisation score ≥8, disease onset at postpartum or greater than 6 months after antecedent pregnancy), metastatic GTT, recurrent/resistant GTT after chemotherapy, or post-molar GTT with unexplained abnormal β-hCG regression and patients undergoing re-evaluation after salvage treatment were enrolled. PET was undertaken within 1 week after computed tomography (CT). Clinical impacts of additional PET were determined on a scan basis.
A total of 14 patients were recruited. Sixteen PET scans were performed, with one patient having three serial studies. Benefits of additional PET were seen in 7 of 16 (43.8%) scans; these benefits included disclosure of chemotherapy-resistant lesions (n=2), exclusion of false-positive CT lesions (n=1), detection of an additional lesion not found by conventional imaging (n=1) in high-risk GTT at the start of primary chemotherapy, and confirmation of complete response to treatment for PSTT or to salvage therapy for recurrent/resistant GTT (n=3). On the other hand, in two instances there were false-negative PET findings, six scans yielded no benefit, and one showed an indeterminate lesion.
Our preliminary results suggest that 18F-FDG PET is potentially useful in selected patients with GTT by providing precise mapping of metastases and tumour extent upfront, by monitoring treatment response and by localising viable tumours after chemotherapy. A larger study is necessary to further define the role of 18F-FDG PET in GTT.
Keywords18F-FDG PET Gestational trophoblastic tumour β-hCG Chemoresistant
This work was supported by grants from Chang Gung Memorial Hospital (CTRP 91-017) and the National Science Council of Taiwan (NSC 91-2314-B-182A-157 and NSC 92-2314-B-182A-184).
- 16.World Health Organization. Gestational trophoblastic diseases. WHO Technical Report Series. Switzerland: WHO; 1983. p. 692Google Scholar
- 21.Lotz JP, Andre T, Donsimori R, Firmin C, Bouleuc C, Bonnak H, et al. High dose chemotherapy with ifosfamide, carboplatin, and etoposide combined with autologous bone marrow transplantation for the treatment of poor-prognosis germ cell tumours and metastatic trophoblastic disease in adults. Cancer 1995;75:874–85PubMedGoogle Scholar