Pre-operative positron emission tomography scan is associated with lower rates of adjuvant treatment in surgically treated patients with cervical cancer: a 4C Working Group study.

OBJECTIVE: Pre-operative imaging has the potential to improve selection of surgical candidates in early-stage cervical cancer, but limited evidence exists on its association with post-operative adjuvant treatment. This study investigated the role of imaging in candidate selection for radical surgery and its association with the need for adjuvant treatment in early-stage cervical cancer. METHODS: Retrospective analysis was performed using the Canadian Cervical Cancer Collaborative (4C) database of surgical cases from 11 tertiary centers between 2007 and 2017. All patients with squamous, adenocarcinoma, or adenosquamous histology, staged IAI to IIIC per the International Federation of Gynecology and Obstetrics 2018 system, who underwent primary surgical treatment with radical hysterectomy or trachelectomy were included. Groups were defined as no pre-operative imaging, computed tomography (CT) only, magnetic resonance imaging (MRI) with or without CT ("MRI"), or positron emission tomography (PET) with or without MRI or CT ("PET"). Regression analyses estimated associations of pre-operative imaging with adjuvant treatment, recurrence, and death. RESULTS: A total of 1103 patients were analyzed. PET use increased over the study period. Imaging modality was not associated with odds of lymph node spread (p =.16). Pre-operative PET was associated with decreased odds of adjuvant therapy compared with CT only (adjusted odds ratio 0.35; 95% confidence interval 0.18 to 0.66, p <.001) after controlling for other factors including site and year of surgery, age, surgical approach, and histology. No associations between imaging modality and recurrence-free survival or overall survival were observed. CONCLUSIONS: PET use before radical surgery for early-stage cervical cancer was associated with decreased odds of adjuvant treatment but no significant difference in oncologic outcomes. Future studies may refine our understanding of the predictive performance of multi-modal imaging for adjuvant treatment and prognosis.