Accuracy of preoperative cross-sectional imaging in cervical cancer patients undergoing primary radical surgery

Radical hysterectomy or chemoradiotherapy for clinically early-stage cervical cancer with suspicious lymph nodes on imaging: a retrospective cohort study

OBJECTIVE

The optimal treatment of clinically early-stage cervical cancer with suspicious lymph nodes on pretreatment imaging is unclear. Therefore, we aimed to compare surgery (i.e., radical hysterectomy and pelvic lymphadenectomy±adjuvant therapy) with primary chemoradiotherapy as treatment strategies in this patient group regarding recurrence-free, overall survival and toxicity.

METHODS

Women diagnosed between 2009-2017 with the International Federation of Gynecology and Obstetrics (2009) stage IA-IIA and suspicious nodes based on radiologic assessment of pretreatment imaging were retrospectively selected from the Netherlands Cancer Registry. Cox proportional hazard was used to estimate survival and logistic regression for toxicity. Inverse probability weighting was used to correct for confounding. Grade ≥2 surgery-related (≤30 days) and grade ≥3 chemotherapy or radiotherapy-related (≤6 months) toxicity were collected. Missing data were imputed.

RESULTS

Of 330 patients included, 131 (40%) received surgery (followed by adjuvant therapy in 54%) and 199 (60%) chemoradiotherapy. Pathological nodal status was known in 100% of the surgery group and 32% (n=63) of the chemoradiotherapy group, of whom 43% (56/131) and 89% (56/63), respectively, had metastases. After adjustment for confounders, the recurrence-free survival (hazard ratio [HR]=0.67; 95% confidence interval [CI]=0.34-1.31) and overall survival (HR=0.75; 95% CI=0.38-1.47) were not significantly different between both groups, while surgery was associated with more toxicity (odds ratio=2.82; 95% CI=1.42-5.60), mainly surgery-related.

CONCLUSION

In patients with clinically early-stage cervical cancer and suspicious nodes on imaging, surgery and primary chemoradiotherapy yielded comparable results in terms of survival, whereas surgery might be associated with more (surgery-related) short-term toxicity.

Assessing the Efficacy of 18F FDG PET-CT in Preoperative Staging of Early-Stage Cervical Cancer in Novi Sad, Serbia-A Pilot Study

Background and Objectives: This study primarily aims to evaluate the preoperative staging effectiveness of PET-CT in early-stage cervical cancer, particularly, its ability to detect primary tumors and micrometastases. Materials and Methods: In this retrospective study, cervical cancer patients who had undergone preoperative 18F FDG PET-CT scans and were treated at the Department of Gynecology, Institute of Oncology, Vojvodina, in Sremska Kamenica, during the period from 2016 to 2020 were analyzed. Results: The study included 62 patients (mean age, 49.3 ± 9.6 years). Squamous cell carcinoma was the predominant histological type (95.2%), with G2 differentiation (82.3%) and FIGO stage Ib1 (80.6%) being the most common. Assessed by 18F FDG PET-CT, the mean tumor size was 26.4 ± 10.8 mm, which is slightly lower than the 26.9 mm measured during clinical examination (p = 0.784), with a significant (r = 0.678, p < 0.001) correlation between these methods. 18F FDG PET-CT demonstrated an overall accuracy of 88.7% for identifying primary tumors, with a sensitivity of 86.8%, specificity of 100.0%, PPV of 100.0%, and NPV of 56.2%. An intraoperative examination showed identical overall accuracy but higher sensitivity (98.1%) and lower specificity (33.3%). For 18F FDG PET-CT, the level of agreement with the histopathological examination was good (Kappa 0.656), while for the intraoperative examination, it was moderate (Kappa 0.409). Regarding the lymph node assessment, 18F FDG PET-CT's accuracy was 82.2%, with a sensitivity of 53.8% and a specificity of 89.8%. The intraoperative examination showed lower accuracy (66.1%) but higher sensitivity (76.9%). The 18F FDG PET-CT Kappa value indicated moderate agreement (0.449), while the intraoperative examination showed poor agreement (0.282). Conclusions: In conclusion, significant effectiveness is shown by 18F FDG PET-CT for preoperative staging of early-stage cervical cancer, offering superior accuracy in detecting primary tumors and micrometastases, particularly in predicting lymph node metastases, thereby enhancing diagnostic accuracy and informing treatment decisions.

Comparative Diagnostic Value of 18F-FDG-PET-CT and Intraoperative Examination in Cervical Cancer Staging

Background and Objectives: The primary objective of this study is to assess the effectiveness of 18F-FDG-PET-CT in preoperative staging of cervical cancer, focusing on determining surgical operability and exploring the correlation between its quantitative parameters and clinicopathological characteristics. Materials and Methods: This retrospective study included 62 cervical cancer patients treated at the Department of Gynecology, Clinic for Operative Oncology at the Institute of Oncology Vojvodina between January 2016 and January 2020, where preoperative clinical examinations and 18F-FDG-PET-CT were performed to assess the extent of cancer, followed by intraoperative and pathohistological examinations of surgically removed specimens to provide a comprehensive evaluation. Results: The mean tumor size measured by 18F-FDG-PET-CT was slightly greater than that obtained through clinical examination (26.4 mm vs. 26.0 mm), with a strong linear correlation (r = 0.678, p < 0.001) observed between the two measurement methods. The overall prediction accuracy of 18F-FDG-PET-CT for primary tumors is 88.7% (55/62) [sensitivity 86.8%, specificity 100.0%, PPV 100.0%, NPV 56.2%] and for intraoperative examination is 88.7% (55/62) [sensitivity 98.1%, specificity 33.3%, PPV 89.7%, NPV 75.0%]. The agreement with histopathological examination was good for 18F-FDG-PET-CT and moderate for intraoperative examination for primary tumors. Regarding lymph nodes, the overall prediction accuracy of 18F-FDG-PET-CT is 82.2% (51/62) [sensitivity 53.8%, specificity 89.8%, PPV 58.3%, NPV 88.8%] and for intraoperative examination 66.1% (41/62) [sensitivity 76.9%, specificity 63.3%, PPV 35.7%, NPV 91.2%]. The agreement with histopathological examination was moderate for 18F-FDG-PET-CT and poor for intraoperative examination for lymph node metastasis, highlighting that the overall accuracy of 18F-FDG-PET-CT (82.1%) was significantly higher than that of intraoperative examination (66.1%) (p = 0.002). Conclusions: In conclusion, 18F-FDG-PET-CT provides high accuracy in detecting primary tumors and superior predictive value for lymph node metastases compared to intraoperative examination, highlighting the importance of incorporating this imaging modality into the preoperative evaluation process to enhance diagnostic precision and inform treatment decisions.

Diagnostic accuracy of MRI, CT, and [18F]FDG-PET-CT in detecting lymph node metastases in clinically early-stage cervical cancer - a nationwide Dutch cohort study

OBJECTIVES

Imaging is increasingly used to assess lymph node involvement in clinically early-stage cervical cancer. This retrospective study aimed to evaluate the diagnostic accuracy of MRI, CT, and [18F]FDG-PET-CT.

METHODS

Women with International Federation of Gynaecology and Obstetrics (FIGO) 2009 stage IA2-IIA cervical cancer and pretreatment imaging between 2009 and 2017 were selected from the Netherlands Cancer Registry. Patient-based and region-based (i.e. pelvic and common iliac) nodal status was extracted from radiology reports. Pathology results were considered the reference standard for calculating accuracy indices. Multiple imputation was used for missing pathology to limit verification bias risk.

RESULTS

Nodal assessment was performed in 1676 patients with MRI, 926 with CT, and 379 with [18F]FDG-PET-CT, with suspicious nodes detected in 17%, 16%, and 48%, respectively. [18F]FDG-PET-CT was used to confirm MRI/CT results in 95% of patients. Pathology results were imputed for 30% of patients. [18F]FDG-PET-CT outperformed MRI and CT in detecting patient-based nodal metastases with sensitivities of 80%, 48%, and 40%, and AUCs of 0.814, 0.706, and 0.667, respectively, but not in specificity: 79%, 92%, and 92%. Region-based analyses showed similar indices in the pelvic region, but worse performance in the common iliac region with AUCs of 0.575, 0.554, and 0.517, respectively.

CONCLUSIONS

[18F]FDG-PET-CT outperformed MRI and CT in detecting nodal metastases, which may be related to its use as a verification modality. However, MRI and CT had the highest specificity. As MRI is generally performed routinely to assess local and regional spread of cervical cancer, [18F]FDG-PET-CT can be used to confirm suspicious nodes.

CRITICAL RELEVANCE STATEMENT

Accurate assessment of the nodal status in clinically early-stage cervical cancer is essential for tumour staging, treatment decision making and prognosis.

KEY POINTS

• The accuracy of MRI, CT or [18F]FDG-PET-CT for nodal staging in early cervical cancer is a subject of discussion. • Overall, [18F]FDG-PET-CT outperformed MRI, followed by CT, when used as a verification modality. • Staging with MRI and the addition of [18F]FDG-PET-CT to verify high-risk cases seems to be a good approach.