The value of F-18 FDG-PET in invasive cervical cancer
Date
2014-03-31
Authors
Mahomed, Faiza
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Abstract
Uterine Cervical Cancer is one of the leading causes of morbidity amongst the female
genital tract cancers. This study aims to identify the Value of Fluorine-18 - FluorinedeoxyGlucose –
Positron emission tomography scan in cervical cancer. Currently, the International Federation of
Gynaecology and Obstetrics (FIGO) staging is the routine method used internationally for staging of
cervical cancer. This staging is based on clinical criteria and does not take into account para-aortic
lymph nodes or pelvic lymph node involvement, which may affect the radiation target volumes. F-18-
FDG-PET/CT scanning can identify metabolically active lymph nodes as well as distant metastases
including para-aortic lymph nodes. This method aims to show that many patients in our setting have
distant metastases; hence the current FIGO staging method may not be a very accurate method of
staging in the Pre-treatment setting.
F-18 FDG-PET/CT was done post radiation therapy to assess response to treatment. Post treatment
F-18 FDG PET/CT was correlated to clinical findings and responses after radiation. Radiation target
volumes may be modified in future if para-aortic lymph nodes are found on pre-treatment F-18
FDG-PET/CT scan and extended field radiation will then be used. When a large primary tumour is
found with no disease beyond the pelvis, patients may benefit from 3D Brachytherapy.
Methodology: This was a prospective randomised trial done at Charlotte Maxeke Johannesburg
Academic Hospital, between May 2010 and Jan 2012 .After the routine tests were done and patients
staged according to FIGO staging, patients had a Pre-Radiation F-18 FDG-PET/CT scan, followed
by a post therapy F-18 FDG-PET/CT scan 3 months after treatment. Patients were stratified from
clinical stages IBi to stage IIIB.All patients were biopsy confirmed with invasive cervical cancer.
Results: In future, the role of F-18 FDG-PET/CT will be an important modality in the initial staging as
well as in the post therapy setting to assess the response of radiation in cervical cancer. The results
showed that there was no association between FIGO clinical staging and findings in a pre-radiation
F-18 FDG -PET/CT scan as para-aortic lymph nodes were not detected by FIGO staging.
Conclusion: The current staging used for cervical cancer does not correlate with pre -treatment PET
findings. A large proportion of patients were upstaged by F-18 FDG-PET/CT scan. A proportion of
patients were not identified prior to F-18 FDG- PET/CT scan, as having distant metastases. The
value of F18 FDG-PET/CT scan may have an impact on the future management of patients with
cervical cancer. PET in the post therapy setting is also a good surrogate endpoint for determining
tumour control as well as residual and metastatic disease.