Diagnosis of recurrent uterine cervical cancer: computed tomography versus positron emission tomography

Cervical cancer - staging and restaging with 18F-FDG PET/CT

The Guidelines Project, an initiative of the Brazilian Medical Association, aims to combine information from the medical field in order to standardize producers to assist the reasoning and decision-making of doctors. The information provided through this project must be assessed and criticized by the physician responsible for the conduct that will be adopted, depending on the conditions and the clinical status of each patient.

Clinical Value of Combining 18F-FDG PET/CT and Routine Serum Tumor Markers in The Early Detection of Recurrence Among Follow-up Patients Treated for Cervical Squamous Cell Carcinoma

Objective: The purpose of this retrospective study was to investigate the role of 18F-Fluorodeoxyglucose Positron Emission Tomography (¹⁸F-FDG PET/CT) and evaluate if combined elevated serum tumor markers levels improve the accuracy of ¹⁸F-FDG PET/CT in detecting recurrence of cervical squamous cell carcinoma. Methods: A total number of 42 patients who were treated for cervical squamous cell carcinoma and had underwent ¹⁸F-FDG PET/CT for suspected recurrence of cervical cancer were retrospectively reviewed in this study and their clinical, pathological and serological data were collected and analyzed. The clinical value of combining ¹⁸F-FDG PET/CT with serum tumor markers was investigated. Results: Among the 42 patients, ¹⁸F-FDG PET/CT was true positive in 25 (59.5%), false positive in 5 (11.9%), true negative in 12 (28.5%) and false negative in none. The overall patient-based sensitivity, specificity, accuracy, positive predictive value and negative predictive value of ¹⁸F-FDG PET/CT in detecting recurrent cervical cancer were 100%, 70.6, 88.1%, 83.3%, and 100%, respectively. The accuracy of ¹⁸F-FDG PET/CT with combined squamous cell carcinoma antigen (SCC Ag) and carcinoembryonic antigen (CEA) elevation was 100% compared to only SCC Ag elevation and only CEA elevation, 90% and 33.3%, respectively. The positive predictive value of a positive ¹⁸F-FDG PET/CT with combined SCC Ag and CEA elevation was 100% for detection of recurrent cervical cancer. Also, the negative predictive value of a negative ¹⁸F-FDG PET/CT combined with normal SCC Ag and CEA levels was 100%. Conclusion:¹⁸F-FDG PET/CT is highly sensitive in the diagnosis of recurrent cervical cancer. When ¹⁸F-FDG PET/CT is associated with both SCC Ag and CEA elevation or only SCC Ag elevation, the accuracy is increased but not when associated with only CEA elevation. Positive ¹⁸F-FDG PET/CT associated with both tumor markers elevation can precisely predict recurrence. Moreover, normal levels of both tumor markers with a negative ¹⁸F-FDG PET/CT result may clinically reassure that a recurrence is absent.

Comparative Study of Positron Emission Tomography/Computed Tomography and Computed Tomography in the Evaluation of Post-treatment Carcinoma Cervix Patients

Purpose of Study:

To evaluate and compare imaging findings using computed tomography (CT) alone and positron emission tomography/CT (PET/CT) fusion imaging in posttreatment carcinoma cervix patients for recurrence.

Subjects and Methods:

From June 2014 to May 2016, 50 posttreatment carcinoma cervix patients were referred to our institution for PET/CT imaging. In all 50 of these patients referred for evaluation, a reliable reference standard was available. The reference standard was established by histopathological examination of accessible locoregional and nodal/distant metastatic involvement or follow-up of patients. CT and PET/CT were performed and analyzed for locoregional, pelvic nodal, and distant metastasis involvement in posttreatment carcinoma cervix cases.

Results:

In the evaluation of locoregional involvement, CT alone was found to have a sensitivity of 75% and specificity of 90% while PET/CT was found to have a sensitivity of 95% and specificity of 100%. Furthermore, in evaluation of pelvic nodal involvement, CT alone was found to have a sensitivity of 72% and specificity of 92.6% while PET/CT was found to have a sensitivity of 95.5% and specificity of 92.9%. In context to distant metastasis involvement (including para-aortic nodes), CT alone was found to have a sensitivity of 91.7% and specificity of 96.2% while PET/CT was found to have a sensitivity of 95.8% and specificity of 100%. PET/CT fusion in comparison to CT alone is better in sensitivity and specificity in the detection of locoregional involvement, pelvic node invasion, and distant metastasis in posttreatment carcinoma cervix cases.

Multimodality imaging of locally recurrent and metastatic cervical cancer: emphasis on histology, prognosis, and management

The management of recurrent and metastatic cervical cancer is evolving in concert with the available advanced imaging techniques and molecular targeted therapy. The purpose of this review is to provide an overview of imaging and treatment of cervical cancer patients with locoregional recurrence and metastatic disease, with emphasis on characteristic patterns of spread based on histology (squamous cell carcinoma and other subtypes), prognostic factors, diagnosis, and treatment response assessment, as well as updated therapeutic options.

Positron emission tomography alone, positron emission tomography-computed tomography and computed tomography in diagnosing recurrent cervical carcinoma: a systematic review and meta-analysis

INTRODUCTION

The aim of the study was to assess systematically the accuracies of positron emission tomography (PET), PET/computed tomography (CT), and CT in diagnosing recurrent cervical cancer.

MATERIAL AND METHODS

We searched for articles published from January 1980 to June 2013 using the following inclusion criteria: articles were reported in English; the use of PET, interpreted with or without the use of CT; use of CT to detect recurrent cervical cancer; and histopathologic analysis and/or close clinical and imaging follow-up for at least 6 months. We extracted data to calculate sensitivity, specificity, summary receiver operating characteristic curves, and the area under the receiver operating characteristic curve (AUC) as well as test for heterogeneity.

RESULTS

In 23 included studies, PET had the highest pooled specificity at 92% (95% CI: 90-94), whereas PET/CT had the highest pooled sensitivity at 94% (95% CI: 90-97). The area under the curve (AUC) of PET alone, PET/CT, and CT were 0.9594, 0.9508, and 0.9363, respectively. Results of the pairwise comparison between each modality show that the specificity of PET was higher than that of PET/CT (p < 0.05). The difference in the pooled sensitivities and AUC of PET alone and PET/CT showed no statistical significance. No evidence of publication bias was found. However, evidence of heterogeneity was observed.

CONCLUSIONS

The PET/CT may be a useful supplement to current surveillance techniques, particularly for patients with negative CT imaging. However, in terms of diagnostic accuracy, interpreted CT images may have limited additional value to PET in detecting recurrent cervical cancer.

Evaluating PET-CT in the detection and management of recurrent cervical cancer: systematic reviews of diagnostic accuracy and subjective elicitation

BACKGROUND

Positron emission tomography-computed tomography (PET-CT) is recommended to triage women for exenterative surgery and surveillance after treatment for advanced cervical cancer.

OBJECTIVE

To evaluate diagnostic accuracy of additional whole body PET-CT compared with CT/magnetic resonance imaging (MRI) alone in women with suspected recurrent/persistent cervical cancer and in asymptomatic women as surveillance.

DESIGN

Systematic reviews. Subjective elicitation to supplement diagnostic information.

SEARCH STRATEGY/SELECTION CRITERIA/DATA COLLECTION AND ANALYSIS

Searches of electronic databases were performed to June 2013. Studies in women with suspected recurrent/persistent cervical cancer and in asymptomatic women undergoing follow up with sufficient numeric data were included. We calculated sensitivity, specificity and corresponding 95% confidence intervals. Meta-analyses employed a bivariate model that included a random-effects term for between-study variations (CT studies) and univariate random effects meta-analyses (PET-CT studies) for sensitivity and specificity separately.

SUBJECTIVE ELICITATION

Prevalence of recurrence and the accuracy of imaging elicited using the allocation of points technique. Coherence of elicited subjective probabilities with estimates in the literature examined.

RESULTS

We identified 15 relevant studies; none directly compared additional PET-CT with MRI or CT separately. Most CT and MRI studies used older protocols and the majority did not distinguish between asymptomatic and symptomatic women. Meta-analysis of nine PET-CT studies in mostly symptomatic women showed sensitivity of 94.8 (95% CI 91.2-96.9), and specificity of 86.9% (95% CI 82.2-90.5). The summary estimate of the sensitivity of CT for detection of recurrence was 89.64% (95% CI 81.59-94.41) and specificity was 76% (95% CI 43.68-92.82). Meta-analysis for MRI test accuracy studies was not possible because of clinical heterogeneity. The sensitivity and specificity of MRI in pelvic recurrence varied between 82 and 100% and between 78 and 100%, respectively. Formal statistical comparisons of the accuracy of index tests were not possible. Subjective elicitation provided estimates comparable to the literature. Subjective estimates of the increase in accuracy from the addition of PET-CT were less than elicited increases required to justify the use in PET-CT for surveillance.

CONCLUSION

Evidence to support additional PET-CT is scarce, of average quality and does not distinguish between application for surveillance and diagnosis. Guidelines recommending PET-CT in recurrent cervical cancer need to be reconsidered in the light of the existing evidence base.

Usefulness of F-18 FDG PET/CT in Assessment of Recurrence of Cervical Cancer After Treatment

OBJECTIVE

Until now, serum tumor markers, physical examination, and conventional imaging modalities, such as CT or MRI, have been used in assessment of recurrence of cervical cancer after treatment. However, CT and MRI provide only anatomical data, which makes analysis of post-treatment change difficult. This study aims to explore the effectiveness of PET/CT, a new scanning device that combines PET and CT, in evaluation of cervical cancer lesions in patients with suspected recurrence.

METHODS

We studied 51 patients suspected of recurrence among those who underwent F-18 FDG PET/CT for cervical cancer follow-up at Gachon University Gil Hospital between June 2006 and August 2009. Patients were considered to be at risk for recurrence if they reported symptoms that were clinically suggestive of recurrence, or if physical examination showed abnormalities, serum tumor marker levels rose, or follow-up images revealed changes, such as new lesions or swelling of previous sites. Sensitivity, accuracy, specificity, and positive and negative predictive values of PET/CT were measured.

RESULTS

A total of 37 patients were confirmed with recurrence or metastasis, 13 of whom were diagnosed histologically. Measured across all patients, PET/CT scored 97.3% on sensitivity, 71.4% on specificity, a positive predictive value of 90%, a negative predictive value of 90.9%, and an accuracy of 90.2%. PET/CT yielded only one false negative diagnosis and four false positives.

CONCLUSION

As F-18 FDG PET/CT has high sensitivity and negative predictive value in diagnosis of recurrent cervical cancers, it is expected that it will be useful for clinical determination of recurrence and prevention of unnecessary additional treatments. The hope is that a future study on a larger scale will contribute further to determination of the efficacy of PET/CT.

Gynecological cancers

The clinical problems raised in patients presenting with all forms of gynecological malignancy are currently addressed using conventional cross-sectional imaging, usually MRI. In general, F-18 FDG PET-CT has not been shown to have a clinical role in any of these cancers at presentation, although studies are under way to use this form of metabolic imaging to predict prognosis and the response to treatment. Although F-18 FDG PET-CT is superior to conventional imaging techniques, it is only moderately sensitive in demonstrating lymph node metastasis preoperatively, and is inadequate for local staging of patients with endometrial cancer. In ovarian cancer, F-18 FDG PET-CT provides an accurate assessment of the extent of disease, particularly in areas difficult to assess for metastases by CT and MRI such as the abdomen and pelvis, mediastinum, and supraclavicular region. F-18 FDG PET-CT is a sensitive method of detecting pelvic and para-aortic lymph nodal disease in cervical cancer, and appears to be superior to MRI and CT despite the limitations in identifying small foci of disease. In the main, as elsewhere in patients with cancer, the value of PET-CT is in identifying and defining the extent of recurrent disease, in distinguishing between posttreatment fibrosis and recurrence, and possibly in monitoring response to therapy.

18 Fluoro-2deoxy-d-Glucose-Positron Emission Tomography and Locally Advanced Cervical Cancer

Introduction:

The aim of this study was to compare 18 fluoro-2deoxy-d-glucose-positron emission tomography (FDG-PET) after chemoradiation to histological findings after lymphadenectomy and radical hysterectomy and thus evaluate if FDG-PET could avoid surgery when negative.

Methods:

Twenty-one patients with locally advanced cervical cancer treated by chemoradiation, brachytherapy, and adjuvant surgery were prospectively enrolled. 18 Fluoro-2deoxy-d-glucose-PET was realized 5 weeks after concomitant chemoradiation and compared with histology.

Results:

18 Fluoro-2deoxy-d-glucose-PET assessed residual cervical involvement after chemoradiation with a sensitivity of 27.3%, specificity of 90%, and positive predictive value (PPV) of 75%. The negative predictive value (NPV) and the false-negative rate (FN) were 50%. Among patients with no evidence of disease on FDG-PET but with residual involvement on histology, 75% had residual involvement size under10 mm.

For residual pelvic lymph node involvement, the specificity was 100%, NPV was 83.3%, and FN rate was 16.7%.

For residual paraaortic lymph node involvement, specificity and sensitivity were 100%, but only 1 patient was concerned. Considering all the lymph node locations, sensitivity was 20%, specificity 100%, PPV 100%, and NPV 90%.

Considering all localizations for each patient, control FDG-PET had a 30% sensitivity, 87% specificity, 80% PPV, and 43% NPV. False-negative rate was 43%.

Conclusion:

The aim of this study was to evaluate if control FDG-PET might avoid surgery for patients with a negative screening. Although FDG-PET is an interesting diagnostic test for residual lymph node involvement evaluation, it seems not accurate enough to be the only element of the surgery's indication. However, our sample size was too small to definitely conclude.

Survivorship, late effects and cancer of the cervix

As the prevention and treatment of cervical cancer improves, there is increasing focus on the months and years after cancer treatment. Of those women living after a diagnosis of cancer, 10% will have a gynaecological malignancy and although the incidence of cervix cancer has dropped over the last 20 years, so has the age at diagnosis, with more than 60% surviving at least 5 years. In a recent report, 63% of 231 064 US survivors of cervix cancer were more than 10 years from diagnosis. More survivors are living long enough to develop chronic treatment-related conditions. The 2007 English Cancer Reform Strategy highlighted the importance of cancer survivorship and uses the US National Coalition for Cancer Survivorship definition-'living through and beyond cancer'. The emerging picture is of populations living after a diagnosis of cancer without active disease, still having similar health and disability profiles to populations with a diagnosis of a chronic illness. This offers new challenges in identifying and meeting their needs.

Comparison of CT and 18F-FDG pet for detecting peritoneal metastasis on the preoperative evaluation for gastric carcinoma

OBJECTIVE

The aim of our study was to compare the accuracy of CT and (18)FFDG PET for detecting peritoneal metastasis in patients with gastric carcinoma.

MATERIALS AND METHODS

One-hundred-twelve patients who underwent a histologic confirmative exam or treatment (laparotomy, n = 107; diagnostic laparoscopy, n = 4; peritoneal washing cytology, n = 1) were retrospectively enrolled. All the patients underwent CT and (18)F-FDG PET scanning for their preoperative evaluation. The sensitivities, specificities and accuracies of CT and (18)FFDG PET imaging for the detection of peritoneal metastasis were calculated and then compared using Fisher's exact probability test (p < 0.05), on the basis of the original preoperative reports. In addition, two board-certified radiologists and two board-certified nuclear medicine physicians independently reviewed the CT and PET scans, respectively. A receiver-operating characteristic curve analysis was performed to compare the diagnostic performance of CT and (18)F-FDG PET imaging for detecting peritoneal metastasis.

RESULTS

Based on the original preoperative reports, CT and (18)F-FDG PET showed sensitivities of 76.5% and 35.3% (p = 0.037), specificities of 91.6% and 98.9% (p = 0.035), respectively, and equal accuracies of 89.3% (p = 1.0). The receptor operating characteristics curve analysis showed a significantly higher diagnostic performance for CT (Az = 0.878) than for PET (Az = 0.686) (p = 0.004). The interobserver agreement for detecting peritoneal metastasis was good (kappa value = 0.684) for CT and moderate (kappa value = 0.460) for PET.

CONCLUSION

For the detection of peritoneal metastasis, CT was more sensitive and showed a higher diagnostic performance than PET, although CT had a relatively lower specificity than did PET.

Microvessel density and p53 in detecting cervical cancer by FDG PET in cases of suspected recurrence

PURPOSE

Cervical cancer is the second most frequently diagnosed cancer in women worldwide. About one-third of patients experience recurrent disease. A better chance of survival might be achieved by the early detection of recurrent cervical cancer. [(18)F]fluoro-2-deoxy-D-glucose (FDG) PET could be a promising imaging modality for this purpose, given that FDG PET has high diagnostic efficacy. Ideally, pre-selection of patients should be performed before considering FDG PET. The purpose of this study was to investigate parameters of primary cervical cancer associated with recurrence as a basis for pre-selection of patients in whom FDG PET should be performed.

METHODS

Thirty-eight cervical cancer patients, clinically suspected of having recurrent disease, underwent FDG PET. Tissue from primary tumours and nine histologically confirmed metastases was analysed for biomarkers possibly related to glucose metabolism and prognosis (vascular endothelial growth factor, CD31 for microvessel density, glucose transporter-1, hexokinases I, II and III, Ki67, p53, hypoxia-inducible factor 1alpha, and degree of infiltration by lymphocytes and macrophages).

RESULTS

Based on clinical outcome, sensitivity and specificity of FDG PET were 96% and 100%, respectively. Cox regression revealed microvessel density and p53 (tumour suppressor protein) to be the two most important biomarkers for prediction of recurrence (hazard ratios 2.54 and 2.28, respectively). By combining these two biomarkers in a parallel test, sensitivity and specificity in predicting recurrence were 87% and 71%, respectively. Leave-one-out cross-validation demonstrated predictive validity of a model based on microvessel density and p53.

CONCLUSION

In this first study of its kind, we have demonstrated that microvessel density and p53 profiles could be important in pre-selecting cervical cancer patients for detection of recurrence by FDG PET.

FDG-PET for management of cervical and ovarian cancer

OBJECTIVE

To assess the diagnostic performance of Positron Emission Tomography using fluorodeoxyglucose (FDG-PET) in comparison to conventional imaging modalities in the assessment of patients with cervical and ovarian cancer.

METHODS

Studies published between 1966 and 2003 were identified using an OVID search of the MEDLINE database. Inclusion criteria were use of a dedicated scanner, resolution specified, >/=12 human subjects, clinical follow-up >/=6 months or histopathology as reference standard, and sufficient data provided to construct a two-by-two table. Two reviewers independently abstracted data regarding sensitivity and specificity of PET.

RESULTS

25 studies (15 cervical cancer, 10 ovarian cancer) met inclusion criteria for full text review. For cervical cancer, pooled sensitivity and specificity of PET for aortic node metastasis are 0.84 (95% CI 0.68-0.94) and 0.95 (0.89-0.98). Pooled sensitivity and specificity for detection of pelvic node metastasis are: PET, 0.79 (0.65-0.90) and 0.99 (0.96-0.99); MRI, 0.72 (0.53-0.87) and 0.96 (0.92-0.98). Pooled sensitivity for CT is 0.47 (0.21-0.73) (pooled specificity not available). Pooled sensitivity and specificity of PET for recurrent cervical cancer with clinical suspicion are 0.96 (0.87-0.99) and 0.81 (0.58-0.94). For ovarian cancer, pooled sensitivity and specificity to detect recurrence with clinical suspicion are: PET, 0.90 (0.82-0.95) and 0.86 (0.67-0.96); conventional imaging, 0.68 (0.49-0.83) and 0.58 (0.33-0.80); CA-125, 0.81 (0.62-0.92) and 0.83 (0.58-0.96). When conventional imaging and CA-125 are negative, pooled sensitivity and specificity of PET are 0.54 (0.39-0.69) and 0.73 (0.56-0.87), respectively. When CA-125 is rising and conventional imaging is negative, the pooled sensitivity and specificity of PET are 0.96 (0.88-0.99) and 0.80 (0.44-0.97).

CONCLUSIONS

There is good evidence that PET is useful for the pre-treatment detection of retroperitoneal nodal metastasis in cervical cancer. There is fair evidence that PET is useful for the detection of recurrent cervical cancer. PET is less useful for the detection of microscopic residual ovarian cancer but has fair sensitivity to detect recurrence in the setting of a rising CA-125 and negative conventional imaging studies. Available studies are limited by low numbers of patients and wide confidence intervals.

PET imaging in gynecologic malignancies

FDG-PET has a definite role in detecting lymph node involvement and distant metastases. It has also shown encouraging results in assessing tumor recurrence and restaging, but further studies are required before FDG-PET can be incorporated in routine clinical practice for diagnosis of recurrence. In ovarian cancer, FDG-PET has high sensitivity and specificity in identifying patients with recurrent tumor, but lesion localization is difficult with PET. Normal FDG activity in the gastrointestinal tract and bladder may obscure some lesions. Combined PET/CT can help in localizing lesions and differentiating between pathologic and physiologic uptake in the pelvis and abdomen.

The reproductive tract

Diagnostic imaging has played a major role in the evaluation of patients with the cancers of the reproductive tract. The imaging modalities have included ultrasonography, computed tomography, magnetic resonance imaging, hysterosalpingography, and scintigraphy with radiolabeled monoclonal antibodies. Positron emission tomography (PET) with [F-18]fluorodeoxyglucose also has been shown to be useful in the imaging evaluation of these patients. Clinical applications have included initial staging and posttherapy restaging of disease, detecting metastatic disease, differentiating posttherapy anatomic alterations from recurrent or residual disease, and predicting and evaluating treatment response. In this article, we review the diagnostic utility of dedicated PET and combined PET-computed tomography systems in the imaging assessment of reproductive tract malignancies (excluding prostate cancer) in both sexes with an emphasis on fluorodeoxyglucose applications.

The diagnostic accuracy of 18F-Fluorodeoxyglucose PET/CT in patients with gynecological malignancies

OBJECTIVE

To evaluate the diagnostic accuracy of integrated positron emission tomography/computerized tomography (PET/CT) in patients with gynecological cancer.

METHODS

Fifty-three consecutive patients with gynecologic malignancies were included. The patients were referred to our tertiary center to undergo a PET/CT scan. The sensitivity, specificity, positive predictive value (PPV) and negative predictive value (NPV) of PET/CT were compared with the conventional imaging assessments [CT, magnetic resonance imaging (MRI) and ultrasonography (US)].

RESULTS

All tested values were higher for PET/CT than those for the conventional modalities: sensitivity 0.97 vs. 0.40, specificity 0.94 vs. 0.65, PPV 0.97 vs. 0.70, and NPV 0.94 vs. 0.34, respectively.

CONCLUSION

PET/CT is a reliable modality for assessing the extent of disease in patients with gynecologic malignancy.