To operate or to radiate: the added value of the maximal standardized uptake value in PET–FDG in cervical cancer patients

Metabolic activity determines survival depending on the level of lymph node involvement in cervical cancer

Background

To assess the impact of PET/CT functional parameters on survival, locoregional, and distant failure according to the most distant level of lymph node [¹⁸F]FDG uptake in patients with locally advanced cervical cancer (LACC).

Methods

Retrospective study including 148 patients with LACC treated with concurrent chemoradiotherapy after PET/CT and para-aortic lymph node (PALN) surgical staging. Two senior nuclear medicine physicians reviewed all PET/CT exams and retrieved tumor and lymph node metabolic parameters: SUVmax, MTV, TLG. Oncological outcomes according to metabolic parameters and level of lymph node spread on PET/CT were assessed.

Results

In patients without lymph node uptake on PET/CT, high MTV values of the cervical tumor were associated with DFS (HR = 5.14 95%CI = [2.15–12.31]), OS (HR = 6.10 95%CI = [1.89–19.70]), and time to distant (HR = 4.73 95%CI = [1.55–14.44]) and locoregional recurrence (HR = 5.18 95%CI = [1.72–15.60]). In patients with pelvic lymph node (PLN) uptake but without PALN uptake on [¹⁸F]FDG-PET/CT, high MTV values of the cervical tumor were associated with DFS (HR = 3.17 95%CI = [1.02–9.83]) and OS (HR = 3.46 95%CI = [0.96–12.50]), and the number of PLN fixations was associated with DFS (HR = 1.30 95%CI = [1.10–1.53]), OS (HR = 1.35 95%CI = [1.11–1.64]), and time to distant (HR = 1.35 95%CI = [1.08–1.67]) and locoregional recurrence (HR = 1.31 95%CI = [1.08–1.59]). There was no significant association between cervical tumor metabolic or lymph node metrics and survival outcome in patients with PALN uptake.

Conclusions

Cervical MTV is more accurate than SUVmax to predict survival outcome in patients with locoregional disease confined to the pelvis and should be implemented in routine clinical practice. Prognostic value of metabolic metrics disappears with PALN uptake, which is associated with distant failure in nearly half of patients.

Graphical Abstract

Validity of 18F-fluorodeoxyglucose positron emission tomography/computed tomography for pretreatment evaluation of patients with cervical carcinoma: a retrospective pathology-matched study

OBJECTIVE

The aim of this study was to evaluate the validity of 18F-fluorodeoxyglucose (18F-FDG) positron emission tomography (PET)/computed tomography (CT) for pretreatment evaluation of patients with cervical carcinoma.

METHODS

Retrospective evaluation of 63 patients, diagnosed with stage IA-IIA cervical carcinoma who underwent 18F-FDG PET/CT before surgery, was performed. Sensitivity, specificity, positive predictive value, negative predictive value, likelihood ratios (LRs) of PET/CT for predicting the positive cervix, vagina, uterine body, and lymph node invasion at the surgical specimen was calculated.

RESULTS

Sensitivity, specificity, positive predictive value, and negative predictive value of the positive cervix invasion in PET/CT to detect positive surgical specimen were 88.2%, 75%, 93.8%, and 60%, respectively. The LR+ ratio was 3.5, and the LR- ratio was 0.2. Sensitivity, specificity, positive predictive value, and negative predictive value of the positive vagina invasion in PET/CT to detect positive surgical specimen were 100%, 70.97%, 5.3%, and 100%, respectively. The LR+ ratio was 3.4, and the LR- ratio was 0. Sensitivity, specificity, positive predictive value, and negative predictive value of the positive uterine body invasion in PET/CT to detect positive surgical specimen were 75%, 83.1%, 23.1%, and 98%, respectively. The LR+ ratio was 4.4, and the LR- ratio was 0.3. Sensitivity, specificity, positive predictive value, and negative predictive value of the positive lymph node invasion in PET/CT to detect positive surgical specimen were 87.5%, 78.4%, 38.9%, and 97.6%, respectively. The LR+ ratio was 4.1, and the LR- ratio was 0.2.

CONCLUSIONS

The cervix invasion, negative uterine body invasion, and negative lymph node invasion are effective 18F-FDG PET/CT findings.

The role of F-fluorodeoxyglucose (FDG) positron emission tomography-computed tomography (PET/CT) in the screening of cervical cancer: a literature review

F-fluorodeoxyglucose (FDG) positron emission tomography-computed tomography (PET/CT) has of late gained prominence in the investigation of cervical cancer since it gives a better clarity on imaging modalities for the status of the lymph node and distant metastasis. The current review is an appraisal of the recent updates on the role of FDG-PET/CT in the screening of cervical cancer as evidenced by publications till date. 985 studies were obtained in the initial search on cervical cancer and publications selected based on inclusion and exclusion criteria. In the final selection, 14 were selected and coded as the most appropriate for the present review. Valuable studies on (FDG) PET/CT have been identified. These studies point to the fact that recent advanced protocols like PET/CT supported by therapeutic innovations ensure better cancer care and survival chances in cervical cancer patients.

Adnexal masses requiring surgical intervention in women with advanced cervical cancer

OBJECTIVE

Surgical evaluation of adnexal masses in patients with cervical cancer can be considered in order to optimize treatment outcomes and rule out a second pathologic process. Our objective was to review treatment patterns and outcomes in women with advanced cervical cancer (ACC) and an adnexal mass.

METHODS

A retrospective review was performed with IRB approval of patients treated for advanced cervical cancer at our institution between 1990 and 2011. Patients were identified using institutional databases and tumor registries. Descriptive statistics were performed using Microsoft Excel 2011 and Instat was used to perform Fisher's exact test and student T-tests.

RESULTS

Two hundred twenty eight patients with stage IIB-IVB cervical cancer were identified, 50 (22%) of whom had an adnexal mass on initial imaging studies (31 stage IIB, 15 stage IIIB, 3 stage IVA, 3 stage IVB). The mean follow up time of patients with adnexal masses was 22 months (range 3-128 months). Thirteen of 50 (26%) patients underwent surgical evaluation of the adnexal mass. Six were found to have cervical cancer metastatic to the adnexae, while seven had benign adnexal lesions. Thirty-seven of 50 (74%) patients were conservatively managed. All 37 women had cystic masses <8 cm or complex masses <5 cm in size. Thirty-four of the 37 (92%) patients had resolution of their adnexal mass and 3 were deemed stable on follow up imaging. Twenty three percent of surgically managed patients and 57% of conservatively managed patients had disease recurrence (p=0.05). There were no recurrences in the adnexa.

CONCLUSION

Twelve percent of women with ACC and an adnexal mass have ovarian metastases. Patients with cystic masses less than 8 cm and complex masses less than 5 cm in size can be expectantly managed.

Improving patient access in nuclear medicine: a case study of PET scanner scheduling

We used the systems engineering technique of discrete event simulation modeling to assist in increasing patient access to positron emission tomographic examinations in the Department of Nuclear Medicine at Mayo Clinic, Rochester. The model was used to determine the best universal slot length to address the specific access challenges of a destination medical center such as Mayo Clinic. On the basis of the modeling, a new schedule was implemented in April 2012 and our before and after data analysis shows an increase of 2.4 scans per day. This was achieved without requiring additional resources or negatively affecting patient waiting, staff satisfaction (as evaluated by day length), or examination quality.