The prognostic value of PET and PET/CT in cervical cancer

Clitoral metastasis from squamous cell carcinoma of the cervix on 18F-FDG PET/CT and MRI

Metastasis to the clitoris is extremely rare. Here, we report a highly unusual case of high-grade squamous cell carcinoma of the cervix metastasizing to the clitoris a year following surgery and chemoradiotherapy. The patient presented with a painless clitoral mass identified through physical examination. Magnetic resonance imaging (MRI) showed a diffusely enhancing clitoral mass with hyperintense signals on diffusion-weighted imaging (DWI) and fluid-sensitive T2-weighted (T2W) sequences. This malignant tumor was detected by 18fluorine-fluorodeoxyglucose positron emission tomography/computed tomography (18F-FDG PET/CT) due to its high FDG uptake. Pathological examination confirmed clitoral metastasis. Clitoral metastasis, although exceedingly rare, should be considered in cervical cancer patients presenting with clitoral masses on physical examination and imaging, particularly in those with advanced stages. Our case report is unique because it represents a recurrence in a patient initially diagnosed with early-stage cancer.

Is PET Radiomics Useful to Predict Pathologic Tumor Response and Prognosis in Locally Advanced Cervical Cancer?

This study investigated whether radiomic features extracted from pretreatment [18F]FDG PET could improve the prediction of both histopathologic tumor response and survival in patients with locally advanced cervical cancer (LACC) treated with neoadjuvant chemoradiotherapy followed by surgery compared with conventional PET parameters and histopathologic features. Methods: The medical records of all consecutive patients with LACC referred between July 2010 and July 2016 were reviewed. [18F]FDG PET/CT was performed before neoadjuvant chemoradiotherapy. Radiomic features were extracted from the primary tumor volumes delineated semiautomatically on the PET images and reduced by factor analysis. A receiver-operating-characteristic analysis was performed, and conventional and radiomic features were dichotomized with Liu's method according to pathologic response (pR) and cancer-specific death. According to the study protocol, only areas under the curve of more than 0.70 were selected for further analysis, including logistic regression analysis for response prediction and Cox regression analysis for survival prediction. Results: A total of 195 patients fulfilled the inclusion criteria. At pathologic evaluation after surgery, 131 patients (67.2%) had no or microscopic (≤3 mm) residual tumor (pR0 or pR1, respectively); 64 patients (32.8%) had macroscopic residual tumor (>3 mm, pR2). With a median follow-up of 76.0 mo (95% CI, 70.7-78.7 mo), 31.3% of patients had recurrence or progression and 20.0% died of the disease. Among conventional PET parameters, SUVmean significantly differed between pathologic responders and nonresponders. Among radiomic features, 1 shape and 3 textural features significantly differed between pathologic responders and nonresponders. Three radiomic features significantly differed between presence and absence of recurrence or progression and between presence and absence of cancer-specific death. Areas under the curve were less than 0.70 for all parameters; thus, univariate and multivariate regression analyses were not performed. Conclusion: In a large series of patients with LACC treated with neoadjuvant chemoradiotherapy followed by surgery, PET radiomic features could not predict histopathologic tumor response and survival. It is crucial to further explore the biologic mechanism underlying imaging-derived parameters and plan a large, prospective, multicenter study with standardized protocols for all phases of the process of radiomic analysis to validate radiomics before its use in clinical routine.

Prognostic significance of delayed complete metabolic response on PET/CT after primary chemoradiation treatment of cervical cancer

OBJECTIVE

To investigate the prognostic significance of near-complete metabolic response on initial follow-up PET/CT after primary chemoradiation treatment of cervical cancer.

METHODS

Survival data were retrospectively compared between patients who had complete metabolic response on first follow-up PET/CT, 3 months after chemoradiation (group 1) with those who had near-complete metabolic response on first PET/CT and later showed complete metabolic response at subsequent PET/CT, 6 months or more after treatment (group 2).

RESULTS

Of the 108 patients included in the final analysis, 74 (68.5%) showed complete metabolic response on initial PET/CT, 3 months after treatment, and 34 patients (31.5%) showed complete metabolic response on subsequent PET/CT, 6 months after treatment. Tumor characteristics were comparable between groups. Group 1 had higher percent of stage 1 (12% vs 0%) and lower percent of stage 4 disease (3% vs 14%) than those of group 2. Group 2 patients had significantly fewer cases of recurrences and deaths than group 1 patients (6% vs 26%, p=0.018; 0% vs 20%, p=0.003, respectively), with comparable 3-year survival rates (group 1, 90% vs group 2, 100%, p=0.31). Twelve patients had progressive disease on first follow-up PET/CT; these patients had significantly worse overall survival compared with all other patients (log-rank test, p<0.001). Younger age and delayed complete metabolic response were associated with lower chance of recurrence and death on univariate analysis. On multivariate analysis, delayed complete metabolic response remained significantly associated with no recurrence HR=0.14 (95% CI 0.25 to 0.84), p=0.031.

CONCLUSIONS

Survival outcome of patients with cervical cancer who show residual 18F-fluorodeoxyglucose uptake on initial PET/CT after treatment, but reach complete metabolic response on follow-up PET/CT, is not inferior compared with survival of patients who show complete metabolic response on initial PET/CT 3 months after treatment. Watchful waiting with follow-up PET/CT seems a safe option for these patients.

Prediction of Recurrent Cervical Cancer in 2-Year Follow-Up After Treatment Based on Quantitative and Qualitative Magnetic Resonance Imaging Parameters: A Preliminary Study

PURPOSE

This study investigated predictors of cervical cancer (CC) recurrence from native T1 mapping, conventional imaging, and clinicopathologic metrics.

PATIENTS AND METHODS

In total, 144 patients with histopathologically confirmed CC (90 with and 54 without surgical treatment) were enrolled in this prospective study. Native T1 relaxation time, conventional imaging, and clinicopathologic characteristics were acquired. The association of quantitative and qualitative parameters with post-treatment tumor recurrence was assessed using univariate and multivariate Cox proportional hazard regression analyses. Independent risk factors were combined into a model and individual prognostic index equation for predicting recurrence risk. The receiver operating characteristic (ROC) curve determined the optimal cutoff point.

RESULTS

In total, 12 of 90 (13.3%) surgically treated patients experienced tumor recurrence. Native T1 values (X1) [hazard ratio (HR) 1.008; 95% confidence interval (CI) 1.001-1.016], maximum tumor diameter (X2) (HR 1.065; 95% CI 1.020-1.113), and parametrial invasion (X3) (HR 3.930; 95% CI 1.013-15.251) were independent tumor recurrence risk factors. The individual prognostic index (PI) of the established recurrence risk model was PI = 0.008X1 + 0.063X2 + 1.369X3. The area under the ROC curve (AUC) of the Cox regression model was 0.923. A total of 20 of 54 (37.0%) non-surgical patients experienced tumor recurrence. Native T1 values (X1) (HR 1.012; 95% CI 1.007-1.016) and lymph node metastasis (X2) (HR 4.064; 95% CI 1.378-11.990) were independent tumor recurrence risk factors. The corresponding PI was calculated as follows: PI = 0.011X1 + 1.402X2; the Cox regression model AUC was 0.921.

CONCLUSIONS

Native T1 values combined with conventional imaging and clinicopathologic variables could facilitate the pretreatment prediction of CC recurrence.

Simultaneous integrated or sequential boost to clinically involved lymph nodes in patients with locally advanced cervical cancer treated with definitive chemoradiotherapy

OBJECTIVE

The optimal treatment of metastatic lymph nodes (LNs) in locally-advanced cervical cancer (LACC) is controversial. With the widespread use of modern radiotherapy (RT) techniques, it is become possible to perform dose escalation in clinically involved LNs. This study aimed to evaluate the oncologic outcomes of dose escalation to the involved LNs with the simultaneous-integrated (SIB) or sequential boost (SEB) techniques as a part of definitive chemoradiotherapy (CRT) for patients with LACC.

METHODS

The data of 47 patients treated with definitive CRT with either a SIB or SEB technique to the metastatic LNs between 2015 and 2021 were retrospectively analyzed. All patients received 50.4 Gy/28 fractions of external-beam RT and 28 Gy/4 fractions of brachytherapy.

RESULTS

The number of boosted LNs was 146. The median size of the LNs was 2 cm (range, 1-5 cm). The median cumulative equivalent dose in 2-Gy fractions for the LNs was 64.2 Gy (range, 57.6-71.2 Gy). During the median 30 months of follow-up (range, 14-91 months), no boosted LNs recurred and the local control (LC) rate was 100%. The 2-year overall, disease-free, local recurrence-free, and distant metastasis-free survival rate was 83.1%, 70.5%, 77.5%, and 74.4%, respectively. In multivariate analysis, the non-squamous cell histology was the only negative independent prognostic factor for DFS and DMFS. Treatment was well tolerated without any serious acute toxicity. Serious late toxicity developed in three (6%) patients as ureteral stenosis, rectal bleeding and pelvic fracture in one patient each.

CONCLUSIONS

RT dose escalation provides excellent LC for the clinically involved LNs, even for bulky ones, with a low toxicity profile. Routine LN dissection may not be necessary. However, randomized trials are needed to determine the optimal treatment approach.

Risk of recurrence after chemoradiotherapy identified by multimodal MRI and 18F-FDG-PET/CT in locally advanced cervical cancer

BACKGROUND AND PURPOSE

MRI, applying dynamic contrast-enhanced (DCE) and diffusion-weighted (DW) sequences, and 18F-fluorodeoxyglucose (18F-FDG) PET/CT provide information about tumor aggressiveness that is unexploited in treatment of locally advanced cervical cancer (LACC). We investigated the potential of a multimodal combination of imaging parameters for classifying patients according to their risk of recurrence.

MATERIALS AND METHODS

Eighty-two LACC patients with diagnostic MRI and FDG-PET/CT, treated with chemoradiotherapy, were collected. Thirty-eight patients with MRI only were included for validation of MRI results. Endpoints were survival (disease-free, cancer-specific, overall) and tumor control (local, locoregional, distant). K^trans, reflecting vascular function, apparent diffusion coefficient (ADC), reflecting cellularity, and standardized uptake value (SUV), reflecting glucose uptake, were extracted from DCE-MR, DW-MR and FDG-PET images, respectively. By applying an oxygen consumption and supply-based method, ADC and K^trans parametric maps were voxel-wise combined into hypoxia images that were used to determine hypoxic fraction (HF).

RESULTS

HF showed a stronger association with outcome than the single modality parameters. This association was confirmed in the validation cohort. Low HF identified low-risk patients with 95% precision. Based on the 50th SUV-percentile (SUV₅₀), patients with high HF were divided into an intermediate- and high-risk group with high and low SUV₅₀, respectively. This defined a multimodality biomarker, HF/SUV₅₀. HF/SUV₅₀ increased the precision of detecting high-risk patients from 41% (HF alone) to 57% and showed prognostic significance in multivariable analysis for all endpoints.

CONCLUSION

Multimodal combination of MR- and FDG-PET/CT-images improves classification of LACC patients compared to single modality images and clinical factors.

[F18]FDG PET/CT-Derived Metabolic and Volumetric Biomarkers Can Predict Response to Treatment in Locally Advanced Cervical Cancer Patients

Simple Summary

Carcinoma of the uterine cervix is one of the most common and severe malignancies in women. Up to 40% of locally advanced cervical cancer patients treated with definitive chemoradiation therapy will not respond or will develop disease recurrence. The aim of this retrospective study was to evaluate the relationship between quantitative metabolic and volumetric parameters extracted from FDG PET/CT imaging data and the response rate to definitive chemoradiation therapy in this group of patients. FDG PET/CT studies of 90 cervical cancer patients were analyzed, and it was found that quantitative metabolic and volumetric parameters such as SUVmax, SUVmean, MTV, and TLG are higher in locally advanced cervical cancer patients who will not respond to definitive chemoradiation therapy. Specifically, in patients who are not metastatic at staging, MTV and TLG values can serve as a predictor for treatment response and thus may alter treatment strategy.

Abstract

(1) Purpose: Current study aimed at evaluating the relationship between quantitative metabolic and volumetric FDG PET/CT parameters and the response to definitive chemoradiation therapy in locally advanced cervical cancer patients; (2) Methods: Ninety newly diagnosed locally advanced cervical cancer patients (FIGO IB2-IVA) were investigated. All patients underwent PET/CT at staging and after treatment. Metabolic and volumetric parameters, including SUVmax, SUVmean, Total Lesion Glycolysis (TLG), and Metabolic Tumor Volume (MTV) of the primary tumor and metastatic lymph nodes were measured and compared between patients with and without complete metabolic response (CMR). A similar analysis was performed in a subgroup of FIGO IB2-IIB patients; (3) Results: SUVmax and SUVmean of the primary tumor as well as those of metastatic lymph nodes, MTV, and TLG were found to be significantly different between CMR and non-CMR patients. In a subgroup of patients with FIGO IB2-IIB disease, MTV and TLG identified women who will achieve CMR with a threshold of 31.1 cm³ for MTV and 217.8 for TLG; (4) Conclusions: PET/CT-derived quantitative metabolic and volumetric parameters are higher in locally advanced cervical cancer patients who will not respond to definitive chemoradiation therapy. Specifically, in patients who are not metastatic at staging, MTV and TLG values can serve as a predictor for treatment response and thus may alter treatment strategy.

Prognostic Impact of Total Lesion Glycolysis (TLG) from Preoperative 18F-FDG PET/CT in Stage II/III Colorectal Adenocarcinoma: Extending the Value of PET/CT for Resectable Disease

We investigated the prognostic role of metabolic parameters from preoperative ¹⁸F-FDG PET/CT in stage II/III colorectal adenocarcinoma. A total of 327 stage II/III colorectal adenocarcinoma patients who underwent curative resection were included. The maximal standard uptake value (SUVmax), metabolic tumor volume (MTV), and total lesion glycolysis (TLG) were analyzed for optimal cut-offs and their effect on DFS. Differences in DFS rates and hazard ratios for DFS between cut-offs were statistically significant in SUVmax, MTV2.5, MTV3, TLG 2.5, TLG3, and TLG30%. Factors significantly related to DFS in univariate Cox regression were age, sex, stage, preoperative CEA, SUVmax, MTV2.5, MTV3, TLG2.5, TLG3, and TLG30%. Age, sex, preoperative CEA, and TLG2.5 (p = 0.009) sustained statistically significant difference in multivariate analysis. The 1-, 3-, and 5-year DFS rates for TLG2.5 ≤ 448.5 were 98.1%, 79.6%, and 74.8%, significantly higher than 78.4%, 68.5%, and 61.1% of TLG2.5 > 448.5, respectively (p = 0.012). TLG, a parameter indicating both the metabolic activity and metabolic volume, was the strongest predictor independently associated with DFS, among several PET parameters with statistical significance. These results suggest the potential prognostic value of preoperative ¹⁸F-FDG PET/CT in stage II/III resectable colorectal cancer.

Cervical Cancer Diagnosis: Insights into Biochemical Biomarkers and Imaging Techniques

Cervical malignancy is known as one of the important cancers which is originated from cervix. This malignancy has been observed in women infected with papillomavirus who had regular oral contraceptives, multiple pregnancies, and sexual relations. Early and fast cervical cancer diagnosis is known as two important aspects of cervical cancer therapy. Several investigations indicated that early and fast detection of cervical cancer could be associated with better treatment process and increasing survival rate of patients with this malignancy. Imaging techniques are very important diagnosis tools that could be employed for diagnosis and following responses to therapy in various cervical cancer stages. Multiple lines of evidence indicated that utilization of imaging techniques is related to some limitations (i.e. high cost, and invasive effects). Hence, it seems that along with using imaging techniques, finding and developing new biomarkers could be useful in the diagnosis and treatment of subjects with cervical cancer. Taken together, many studies showed that a variety of biomarkers including, several proteins, mRNAs, microRNAs, exosomes and polymorphisms might be introduced as prognostic, diagnostic and therapeutic biomarkers in cervical cancer therapy. In this review article, we highlighted imaging techniques as well as novel biomarkers for the diagnosis of cervical cancer.

EANM/SNMMI practice guideline for [18F]FDG PET/CT external beam radiotherapy treatment planning in uterine cervical cancer v1.0

PURPOSE

The aim of this EANM / SNMMI Practice Guideline with ESTRO endorsement is to provide general information and specific considerations about [18F]FDG PET/CT in advanced uterine cervical cancer for external beam radiotherapy planning with emphasis on staging and target definition, mostly in FIGO stages IB3-IVA and IVB, treated with curative intention.

METHODS

Guidelines from related fields, relevant literature and leading experts have been consulted during the development of this guideline. As this field is rapidly evolving, this guideline cannot be seen as definitive, nor is it a summary of all existing protocols. Local variations should be taken into consideration when applying this guideline.

CONCLUSION

The background, common clinical indications, qualifications and responsibilities of personnel, procedure / specifications of the examination, documentation / reporting and equipment specifications, quality control and radiation safety in imaging is discussed with an emphasis on the multidisciplinary approach.

PET-detected asymptomatic recurrence is associated with improved survival in recurrent cervical cancer

PURPOSE

We aimed to examine utilization patterns of positron emission tomography scans (PET or PET/CT) beyond 6 months after cervical cancer treatment. We investigated survival outcomes of asymptomatic patients with PET-detected recurrence.

METHODS

We performed a retrospective review of 283 patients with stage IA-IVA cervical cancer treated with primary chemoradiation. The 107 patients (37.8%) with recurrence were categorized as "asymptomatic PET-detected recurrence" (n = 23) or "standard detection" (n = 84) and we compared clinical characteristics and outcomes using multivariate logistic regression analysis.

RESULTS

Late post-treatment PET (≥ 6 months after treatment) was performed in 35.3% (n = 100). Indications for late post-treatment PET included restaging in setting of known recurrence (23.6%), follow up of prior ambiguous imaging findings (9.7%), and new symptoms or exam findings (6.7%). However, late post-treatment PET was most commonly performed outside of current imaging guidelines, in asymptomatic patients without suspicion for recurrence (60.0%), presumably for surveillance. The median time to recurrence was 12.1 months (IQR 7.3-26.6). 23 patients (21.5%) had recurrence detected late post-treatment PET while asymptomatic (n = 23/107). Patients with asymptomatic PET-detected recurrence had improved survival by 26.3 months compared to the standard detection cohort (50.3 vs 24.0 months, p = 0.0015). On multivariate analysis, predictors of survival after recurrence were presence of distant metastases at diagnosis (p = 0.010) and asymptomatic PET-detected recurrence (p = 0.039).

CONCLUSIONS

PET imaging in asymptomatic patients beyond 6 months after treatment may have clinical benefit and warrants further study. Detection of recurrence by PET in asymptomatic patients ≥ 6 months after chemoradiation was associated with prolonged survival by more than   2 years.

The extent of aortic lymphadenectomy in locally advanced cervical cancer impacts on survival

OBJECTIVE

The prognostic impact of surgical paraaortic staging remains unclear in patients with locally advanced cervical cancer (LACC). The objective of our study was to evaluate the results of the surgical technique of preoperative aortic lymphadenectomy in LACC related to tumor burden and disease spread to assess its influence on survival.

METHODS

Data of 1,072 patients with cervical cancer were taken from 11 Spanish hospitals (Spain-Gynecologic Oncology Group [GOG] working group). Complete aortic lymphadenectomy surgery (CALS) was considered when the lymph nodes (LNs) were excised up to the left renal vein. The extent of the disease was performed evaluating the LNs by calculating the geometric means and quantifying the log odds between positive LNs and negative LNs. The Kaplan-Meier method was used to estimate the survival distribution. A Cox proportional hazards model was used to account for the influence of multiple variables.

RESULTS

A total of 394 patients were included. Pathological analysis revealed positive aortic LNs in 119 patients (30%). LODDS cut-off value of -2 was established as a prognostic indicator. CALS and LODDS <-2 were associated with better disease free survival and overall survival than suboptimal aortic lymphadenectomy surgery and LODDS ≥-2. In a multivariate model analysis, CALS is revealed as an independent prognostic factor in LACC.

CONCLUSION

When performing preoperative surgical staging in LACC, it is not advisable to take simple samples from the regional nodes. Radical dissection of the aortic and pelvic regions offers a more reliable staging of the LNs and has a favorable influence on survival.

Prognostic value of posttreatment FEDG-PET imaging following combined chemoradiation therapy in locally advanced cervical cancer

OBJECTIVES

To evaluate the performances of posttreatment FEDG-PET to predict the prognosis of patients treated with concurrent chemoradiotherapy (CT/RT) for locally advanced cervical cancer.

MATERIALS AND METHODS

The medical records of 131 patients treated in 9 French academic institutions for IB2-IIB cervical cancer and for which a posttherapy FEDG-PET was performed were reviewed. All patients received CT/RT, possibly completed with vaginal brachytherapy (VBT) and completion surgery. Posttreatment FEDG-PET was performed within 3 months after completion of CT/RT or VBT. Incomplete metabolic response (IMR) was defined as the persistence of FEDG uptake.

RESULTS

An IMR was identified in 44 (33.6 %) cases. IMR was associated with higher risk of recurrence (aHR = 2.8; 95 %CI: 1.3-5.7; p = 0.006) and death (aHR = 4.5 ;95 %CI: 1.4-13.8; p = 0.009). Completion surgery was performed in 61 (46.9 %) patients with histologic cervical residual disease identified in 31 (50.8 %). FEDG-PET sensitivity and specificity in predicting cervical residual disease following CT/RT was 48.4 % (95 %CI: 30.8-66) and 80 % (95 %CI: 65.7-94.3), respectively.

CONCLUSIONS

In patients treated with CT/RT for locally advanced cervical cancer, despite limited performances to predict cervical residual disease, posttreatment FEDG-PET is predictive of patients' prognosis and long-term outcome.

Guidelines of the Brazilian Society of Oncologic Surgery for pelvic exenteration in the treatment of cervical cancer

BACKGROUND AND OBJECTIVES

The primary treatment for locally advanced cases of cervical cancer is chemoradiation followed by high-dose brachytherapy. When this treatment fails, pelvic exenteration (PE) is an option in some cases. This study aimed to develop recommendations for the best management of patients with cervical cancer undergoing salvage PE.

METHODS

A questionnaire was administered to all members of the Brazilian Society of Surgical Oncology. Of them, 68 surgeons participated in the study and were divided into 10 working groups. A literature review of studies retrieved from the National Library of Medicine database was carried out on topics chosen by the participants. These topics were indications for curative and palliative PE, preoperative and intraoperative evaluation of tumor resectability, access routes and surgical techniques, PE classification, urinary, vaginal, intestinal, and pelvic floor reconstructions, and postoperative follow-up. To define the level of evidence and strength of each recommendation, an adapted version of the Infectious Diseases Society of America Health Service rating system was used.

RESULTS

Most conducts and management strategies reviewed were strongly recommended by the participants.

CONCLUSIONS

Guidelines outlining strategies for PE in the treatment of persistent or relapsed cervical cancer were developed and are based on the best evidence available in the literature.

The role of 18F-FDG-PET/CT in predicting the histopathological response in locally advanced cervical carcinoma treated by chemo-radiotherapy followed by radical surgery: a prospective study

PURPOSE

This prospective study aimed to evaluate whether ¹⁸F-FDG-PET/CT performed before, during and after neoadjuvant chemo-radiotherapy (CRT) could predict histopathological response in patients with locally advanced cervical cancer (LACC) treated with CRT followed by radical surgery.

METHODS

Between October 2010 and June 2014, 88 patients with LACC were enrolled. For each patient, three ¹⁸F-FDG-PET/CT scans (baseline, early and final) were acquired and evaluated by qualitative and quantitative analysis. Maximum standardized uptake value (SUV_max), SUV_mean, metabolic tumor volume (MTV) and total lesion glycolysis (TLG) were measured as absolute values and their percentage variation (delta) (early vs. baseline and final vs. baseline). The role of ¹⁸F-FDG-PET/CT in predicting lymph node (LN) residual disease was evaluated by qualitative analysis only. Histopathology was the reference standard.

RESULTS

At histopathology, 40 patients had complete response (CR, pR0), 48 had partial response (PR: 21 microscopic [pR1] and 27 macroscopic [pR2]). At baseline, SUV_max and SUV_mean were significantly higher in pR0 than in pR1-pR2 patients. At early evaluation, MTV and TLG were significantly higher in pR1-pR2 than in pR0 patients. At final evaluation, SUV_max, SUV_mean and TLG were significantly higher in pR1-pR2 than in pR0 patients. Delta SUV parameters and delta TLG were significantly lower in PR group both during and after CRT. Delta MTV was significantly lower in patients with PR in the early phase only. In receiver operating characteristic (ROC) curve analysis, baseline SUV_mean, early delta TLG, and final delta SUV_max better discriminated PR, providing 83.3%, 67.6% and 85% positive predictive value (PPV) and 60.3%, 90% and 70.8% negative predictive value (NPV), respectively. For LN assessment, high NPV was observed at early and final ¹⁸F-FDG-PET/CT (93.5% and 92.3%, respectively).

CONCLUSION

In LACC patients treated with CRT followed by surgery, early variations in metabolic parameters effectively discriminate histopathological PR of the primary tumor, suggesting the potential role of ¹⁸F-FDG-PET/CT in early personalized treatment. The high NPV of early and final PET/CT could enable "tailored surgery" by avoiding lymphadenectomy in selected patients.

HIV status does not have an impact on positron emission tomography-computed tomography (PET-CT) findings or radiotherapy treatment recommendations in patients with locally advanced cervical cancer

INTRODUCTION

Positron emission tomography-computed tomography (PET-CT) imaging is commonly used to identify nodal involvement in locally advanced cervical carcinoma, but its appropriateness for that purpose among HIV-positive patients has rarely been studied. We analyzed PET-CT findings and subsequent treatment prescribed in patients with locally advanced cervical carcinoma in Cape Town, South Africa.

METHODS

We identified a cohort of consecutive cervical carcinoma patients International Federation of Gynecology and Obstetrics (FIGO) stage IIB to IIIB at our cancer center who underwent a planning 18-fluorodeoxyglucose (¹⁸FDG) PET-CT scan from January 2015 through December 2018. Demographics, PET-CT findings, and subsequent treatment prescribed were recorded. Patients were selected for PET-CT only if they had no signs of distant disease on staging chest X-ray or abdominal ultrasound; were deemed suitable for radical chemoradiation by the multi-disciplinary team; and had normal renal function. HIV-positive patients ideally had to have been established on continuous antiviral therapy for more than 3 months and to have a CD4 cell count above 150 cells/μL. Small cell and neuroendocrine carcinoma cases were excluded from the study. Differences in demographic and clinical measures between HIV-positive and HIV-negative patients were evaluated by means of t-tests for continuous variables and χ² tests for categorical variables.

RESULTS

Over a 4 year period, 278 patients-192 HIV-negative (69.1%) and 86 HIV-positive (30.9%)-met the inclusion criteria. HIV-positive patients had a median CD4 count of 475 cells/µL (IQR 307-612 cells/µL). More than 80% of patients had pelvic nodal involvement, and more than 40% had uptake in common iliac and/or para-aortic nodes. Nodal involvement was not associated with HIV status. Fifty-four patients (19.4%) had at least one site of distant metastatic disease. Overall, 235 patients (84.5%) were upstaged following PET-CT staging scan. Upstaging was not associated with HIV status (HIV-negative 83.9% vs HIV-positive 87.2%; p=0.47). Ten patients who did not return for radiotherapy were excluded from the analysis. Following their PET-CT scan, treatment intent changed for 124 patients (46.3%): 53.6% of HIV-positive patients and 42.9% of HIV-negative patients (p=0.11).

CONCLUSION

We found no differences between HIV-positive or HIV-negative patients in nodal involvement or occult metastases, and PET-CT imaging did not lead to, or justify, treatment differences between the two groups. Future studies will evaluate survival and correlation of upstaging with outcome.

Enhancing prognosis prediction using pre-treatment nodal SUVmax and HPV status in cervical squamous cell carcinoma

BACKGROUND

This study was to evaluate the prognostic value of metabolic parameters on F-18-FDG PET/CT and the status of human papillomavirus (HPV) infection and known prognostic variables for predicting tumor recurrence and investigating a prognostic model in patients with locally advanced cervical cancer treated with concurrent chemoradiotherapy (CCRT).

METHODS

A total of 129 patients with cervical squamous cell carcinoma who underwent initial CCRT were eligible for this study. Univariate and multivariate analyses were performed using traditional prognostic factors, metabolic parameters, and HPV infection. Classification and regression decision tree (CART) was used to establish new classification.

RESULTS

Among 129 patients, 29 patients (22.5%) had recurrence after a median follow-up of 60 months (range, 3-125 months). Tumor size, para-aortic lymph node metastasis, nodal SUVmax, and HPV infection status were identified as independent prognostic factors by multivariate analysis. The CART analysis classified the patients into three groups. The first node was nodal SUVmax, and HPV status was the second node for patients with nodal SUVmax ≤7.49; Group A (nodal SUVmax ≤7.49 and HPV positive, HR 1.0), Group B (nodal SUVmax ≤7.49 and HPV negative, HR 3.56), and Group C (nodal SUVmax > 7.49, HR 10.13). Disease-free survival was significantly different among the three groups (p < 0.001).

CONCLUSION

The nodal SUVmax on F-18 FDG PET/CT and HPV infection status before CCRT are powerful independent prognostic factors for the prediction of disease-free survival in patients with cervical squamous cell carcinoma who underwent initial CCRT. We also suggest a simple prognosis prediction model using pre-treatment FDG PET/CT and HPV genotyping; however, it needs further validation in an independent dataset.

Therapeutic value of surgical paraaortic staging in locally advanced cervical cancer: a multicenter cohort analysis from the FRANCOGYN study group

Background

The prognostic impact of surgical paraaortic staging remains unclear in patients with locally advanced cervical cancer (LACC). The objective of our study was to evaluate the survival impact of surgical staging in patients with LACC and no evidence of paraaortic lymph node (PALN) metastasis on pre-operative imaging work-up.

Methods

Data of 1447 patients with cervical cancer treated between 1996 and 2016 were extracted from maintained databases of 10 French University hospitals. Patients with locally advanced disease (IB2 or more) treated by concurrent chemoradiation therapy (CRT) and no evidence of paraaortic metastasis on pre-operative imaging work-up were selected for further analysis. The Kaplan–Meier method was used to estimate the survival distribution. A Cox proportional hazards model was used to account for the influence of multiple variables.

Results

Six hundred and forty-seven patients were included, 377 (58.3%) with surgical staging and 270 (41.7%) without, with a mean follow up of 38.1 months (QI 13.0–56.0). Pathologic analysis revealed positive lymph nodes in 47 patients (12.5%). In multivariate model analysis, surgical staging remained an independent prognostic factor for DFS (OR 0.64, CI 95% 0.46–0.89, p = 0.008) and OS (OR 0.43, CI 95% 0.27–0.68, p < 0.001). The other significant parameter in multivariate analysis for both DFS and OS was treatment by intracavitary brachytherapy (OR respectively of 0.7 (0.5–1.0) and 0.6 (0.4–0.9), p < 0.05).

Conclusion

Nodal surgical staging had an independent positive impact on survival in patients with LACC treated with CRT with no evidence of metastatic PALN on imaging.

Electronic supplementary material

The online version of this article (10.1186/s12967-018-1703-4) contains supplementary material, which is available to authorized users.

18F-FDG PET/CT in locally advanced cervical cancer: A review

Cervical cancer is the second most common gynecological cancer worldwide. In locally advanced cervical cancer, ¹⁸F-FDG PET/CT has become important in the initial staging, particularly in the detection of nodal and distant metastasis, aspects with treatment implications and prognostic value. The aims of this study were to review the role of ¹⁸F-FDG PET/CT in uterine cervical cancer, according to the guidelines of the main scientific institutions (FIGO, NCCN, SEGO, SEOM, ESGO, and ESMO) and its diagnostic accuracy compared to conventional radiological techniques, as well as to review the acquisition protocol and its utility in radiotherapy planning, response assessment and detection of recurrence.

Prognostic Value of Volume-Based Metabolic Parameters Obtained by 18F-FDG-PET/CT in Patients With Locally Advanced Squamous Cell Cervical Carcinoma

OBJECTIVE

The aim of the study was to assess the prognostic impact of volume-based metabolic F-fluorodeoxyglucose-positron emission tomography/ computed tomography (F-FDG-PET/CT) parameters in patients with stage IB-IVA squamous cell cervical carcinoma (SCCC).

MATERIALS AND METHODS

We reviewed the pretreatment F-FDG-PET/CT records of 67 patients with stage IB-IVA SCCC. The maximum standardized uptake value (SUVmax) of the primary tumor (PSUVmax), highest SUVmax of the whole malignant lesions (WSUVmax), metabolic tumor volume (MTV) of the primary tumor (PMTV), MTV of the whole malignant lesion (WMTV), total lesion glycolysis (TLG) of primary tumor (PTLG), and TLG of the whole malignant lesion (WTLG) were obtained. Univariate and multivariate analyses were performed to assess the predictive values of metabolic parameters.

RESULTS

Twenty-nine patients showed disease progression and 21 patients died during follow-up. In univariate analysis, positive lymph node, WSUVmax of greater than 11, WMTV of greater than 63 cm, and WTLG of greater than 373 adversely affected the progression-free survival (P = 0.004, 0.045, 0.023, and 0.005, respectively). A positive lymph node, WSUVmax of greater than 12, WMTV of greater than 68 cm, and WTLG of greater than 373 significantly adversely affected overall survival (P = 0.002, 0.032, 0.015, and 0.006, respectively). In multivariate analysis, independent prognostic factor for progression-free survival was WTLG (relative risk = 2.384, 95% confidence interval = 1.095-5.187, P = 0.029). Independent prognostic factors for overall survival was WTLG (relative risk = 2.763; 95% confidence interval = 1.107-6.896, P = 0.029).

CONCLUSIONS

Preliminary results indicated that pretreatment WTLG measured by F-FDG-PET/CT could independently predict survival in patients with locally advanced SCCC.

Pretreatment metabolic tumour volume and total lesion glycolysis are not independent prognosticators for locally advanced cervical cancer patients treated with chemoradiotherapy

OBJECTIVE

To evaluate the prognostic significance of metabolic parameters derived from fludeoxyglucose (FDG) positron emission tomography (PET)/CT, in cervical cancer patients treated with concurrent chemoradiotherapy.

METHODS

We retrospectively reviewed medical records from 129 biopsy-proven non-metastatic cervical cancer patients treated with external radiotherapy and intracavitary brachytherapy at our department. Correlation between metabolic parameters and tumour characteristics was evaluated. Prognostic factors for survival, local control and distant metastasis were analysed.

RESULTS

The median follow up for all patients and surviving patients was 30.0 months (range, 3.7-94.7 months) and 50.5 months (range, 14.5-94.7 months), respectively. The 2- and 5-year overall survival (OS) and disease-free survival (DFS) rates were 68 42, 54 and 38%, respectively. The maximum standardized uptake value (SUV_max), SUV_mean, metabolic tumour volume (MTV) and total lesion glycolysis were significantly higher in patients with larger tumours (>4 cm) and partial regression or progressive disease after definitive treatment compared to patients with smaller tumour (≤4 cm) and post-treatment complete response. On univariate analysis, stage, lymph node metastasis, tumour size >4 cm, SUV_max, MTV, SUV_mean and total lesion glycolysis were prognostic factors for OS and DFS. On multivariate analysis, only larger tumour and presence of lymph node metastasis were significant prognostic factors for both OS and DFS. Additionally, extensive stage was a significant prognosticator for DFS.

CONCLUSION

Although, metabolic parameters derived from FDG-PET/CT had a prognostic significance in univariate analysis, the significance was lost in multivariate analysis where tumour stage, size and lymph node status were the only independent parameters. Advances in knowledge: The clinical benefit of using FDG-PET/CT metabolic parameters to evaluate the high-risk patients among cervical cancer patients and to eventually change patient management still needs further clarification.

PET/CT Response Criteria (European Organization for Research and Treatment of Cancer) Predict Survival Better Than Response Evaluation Criteria in Solid Tumors in Locally Advanced Cervical Cancer Treated With Chemoradiation

PURPOSE

To investigate whether the ratio of SUVs measured with F-FDG PET/CT between pretreatment and posttreatment has prognostic value in patients with locally advanced cervical cancer treated with primary chemoradiation therapy.

METHODS

Cases of locally advanced cervical cancer (International Federation of Gynecology and Obstetrics stages IB1 to IVA) treated with a nonsurgical curative modality (172 cases including chemoradiation or radiation therapy) were reviewed. F-FDG PET/CT parameters, including SUVmax and SUVmean, were evaluated by F-FDG PET/CT performed prior to treatment and 6 weeks after the end of treatment. Metabolic response was evaluated according to the European Organization for Research and Treatment of Cancer guidelines and was compared with radiologic response measured according to the Response Evaluation Criteria In Solid Tumours (RECIST).

RESULTS

In total, 142 patients receiving chemoradiation showed radiologic responses (median 56% decrease in maximal diameter), whereas 160 and 146 patients showed metabolic responses measured with SUVmax and SUVmean, respectively (73% decrease in SUVmax; 48% decrease in SUVmean). Radiologic response and metabolic response were significantly correlated for SUVmax and SUVmean (P = 0.0009; P = 0.0457, respectively). Kaplan-Meier analysis revealed significant differences in overall survival and progression-free survival between the responder and nonresponder groups, based on the European Organization for Research and Treatment of Cancer criteria (both P < 0.001), whereas no significant difference was found when using RECIST criteria (P = 0.058, P = 0.088, respectively).

CONCLUSIONS

F-FDG PET/CT parameters are good prognostic markers for the response of cervical cancer patients to concurrent chemoradiation therapy, as compared with the RECIST criteria.

Hypoxia in cervical cancer: from biology to imaging

PURPOSE

Hypoxia imaging may improve identification of cervical cancer patients at risk of treatment failure and be utilized in treatment planning and monitoring, but its clinical potential is far from fully realized. Here, we briefly describe the biology of hypoxia in cervix tumors of relevance for imaging, and evaluate positron emission tomography (PET) and magnetic resonance imaging (MRI) techniques that have shown promise for assessing hypoxia in a clinical setting. We further discuss emerging imaging approaches, and how imaging can play a role in future treatment strategies to target hypoxia.

METHODS

We performed a PubMed literature search, using keywords related to imaging and hypoxia in cervical cancer, with a particular emphasis on studies correlating imaging with other hypoxia measures and treatment outcome.

RESULTS

Only a few and rather small studies have utilized PET with tracers specific for hypoxia, and no firm conclusions regarding preferred tracer or clinical potential can be drawn so far. Most studies address indirect hypoxia imaging with dynamic contrast-enhanced techniques. Strong evidences for a role of these techniques in hypoxia imaging have been presented. Pre-treatment images have shown significant association to outcome in several studies, and images acquired during fractionated radiotherapy may further improve risk stratification. Multiparametric MRI and multimodality PET/MRI enable combined imaging of factors of relevance for tumor hypoxia and warrant further investigation.

CONCLUSIONS

Several imaging approaches have shown promise for hypoxia imaging in cervical cancer. Evaluation in large clinical trials is required to decide upon the optimal modality and approach.

Cardiac metastasis in cervical cancer

Metastasis of cervical carcinoma to the heart is uncommon. Most cases are found during autopsy. These type of metastasis occur mostly in epicardium and myocardium. We present a case report of a patient with carcinoma cervix stage IIIB who presented to the hospital with pitting edema of right lower limb, post 1 year of completion of treatment. PET-CT scan showed FDG avid inguinal, iliac and retroperitoneal lymph nodes, which were bulky on right side causing pedal edema. There was FDG avid uptake seen in right atrial wall and in the atrioventricular groove indicative of metastasis to the heart. Patient refused biopsy or further treatment and hence received best supportive care only. She had a disease free survival of 12 months, and survived for 11 months after being diagnosed with recurrence. Overall survival was 23 months.

Nonsurgical management of cervical cancer: locally advanced, recurrent, and metastatic disease, survivorship, and beyond

Despite the declining incidence of cervical cancer as a result of the introduction of screening programs, globally it remains a leading cause of cancer-related death in women. Outcomes for patients who are diagnosed with anything but early-stage disease remain poor. Here we examine emerging strategies to improve the treatment of locally advanced disease. We discuss emerging biologic data, which are informing our investigation of new therapeutic interventions in persistent, recurrent, and metastatic cervical cancer. We recognize the importance of interventions to improve quality of life and to prevent long-term sequelae in women undergoing treatment. Finally, and perhaps most importantly, we recognize the need for global collaboration and advocacy to improve the outcome for all women at risk of and diagnosed with this disease.

Postoperation of cervical cancer with intestine metastasis: a case report and literature review

Background

Cervical cancer can infiltrate locally and directly spread to adjacent organs including the vagina, peritoneum, urinary bladder, ureters, rectum, and paracervical tissue, but the intestine metastasis from cervical cancer is extremely rare, which can easily be misdiagnosed.

Case presentation

Here, we report a case about a 45-year-old postoperative cervical cancer patient with metastases to small intestine and sigmoid colon who presented abdominal distention and dull pain due to intestinal obstruction. The patient underwent exploratory laparotomy, and two intestinal segments including the tumors were resected. The postoperative pathological diagnosis illustrated sigmoid colon and terminal ileum metastatic squamous cell carcinoma.

Conclusions

This case demonstrates that intestine metastasis must be considered in the differential diagnosis of acute abdomen in patients with cervical cancer even at an early tumor stage.

Dose painting by numbers in a standard treatment planning system using inverted dose prescription maps

BACKGROUND

Dose painting by numbers (DPBN) is a method to deliver an inhomogeneous tumor dose voxel-by-voxel with a prescription based on biological medical images. However, planning of DPBN is not supported by commercial treatment planning systems (TPS) today. Here, a straightforward method for DPBN with a standard TPS is presented.

MATERIAL AND METHODS

DPBN tumor dose prescription maps were generated from (18)F-FDG-PET images applying a linear relationship between image voxel value and dose. An inverted DPBN prescription map was created and imported into a standard TPS where it was defined as a mock pre-treated dose. Using inverse optimization for the summed dose, a planned DPBN dose distribution was created. The procedure was tested in standard TPS for three different tumor cases; cervix, lung and head and neck. The treatment plans were compared to the prescribed DPBN dose distribution by three-dimensional (3D) gamma analysis and quality factors (QFs). Delivery of the DPBN plans was assessed with portal dosimetry (PD).

RESULTS

Maximum tumor doses of 149%, 140% and 151% relative to the minimum tumor dose were prescribed for the cervix, lung and head and neck case, respectively. DPBN distributions were well achieved within the tumor whilst normal tissue doses were within constraints. Generally, high gamma pass rates (> 89% at 2%/2 mm) and low QFs (< 2.6%) were found. PD showed that all DPBN plans could be successfully delivered.

CONCLUSIONS

The presented methodology enables the use of currently available TPSs for DPBN planning and delivery and may therefore pave the way for clinical implementation.

A cornucopia of screening and diagnostic techniques for human papillomavirus associated cervical carcinomas

Cervical carcinoma is one of the major consequences of human papillomavirus (HPV) infections. Although HPV infections of cervix do not always progress to cancer, 90% cases of cervical cancer have been found associated with high risk HPV (hrHPV) infection. Usually, HPV infection is asymptomatic; however, this asymptomatic infection can cause abnormal changes in cervix ultimately leading to cancer development. These changes can be detected by the application of screening tests at regular time intervals. For this purpose, morphological, cytological, and DNA based techniques are available. Nevertheless, abnormal screening tests have only the predictive value for precancerous lesions and thus require further evaluation which is usually done by using diagnostic techniques. So far, colposcopy and histological examination alone were considered as the gold standards for cervical cancer diagnosis. Currently, some tests based on expression level of host cell biomarkers are also being used along with histology for diagnostic purpose. Albeit, these tests have significant specificity and sensitivity values but they are unable to suggest a particular viral genotype involved in infection. Diagnostic methods such as PCR, HPV genotyping assays, microarray, and mRNA based assays are useful to predict the genotypes as well as the quantity of viral load in a host cell. Similarly, these diagnostic procedures have high specificity and sensitivity ranges. However, only few of them are practiced commonly, as approval of these tests as routine diagnostic tests requires clinical validation and cost effectiveness.

Clinical impact of FDG PET-CT on the management of patients with locally advanced cervical carcinoma

AIM

To evaluate the impact of staging FDG PET-CT on the initial management of patients with locally advanced cervical carcinoma (LACC) and any prognostic variables predicting survival.

MATERIALS AND METHODS

Retrospective analysis of consecutive patients undergoing FDG PET-CT for staging of LACC in a single tertiary referral centre, between April 2008 and August 2011. Comparison was made between MRI and PET-CT findings and any subsequent impact on treatment intent or radiotherapy planning was evaluated.

RESULTS

Sixty-three patients underwent FDG PET-CT for initial staging of LACC. Major impact on management was found in 20 patients (32%), a minor impact in five (8%), and no impact in 38 (60%). In those patients where PET-CT had a major impact, 12 had more extensive local nodal involvement, five had occult metastatic disease, two had synchronous tumours, and one patient had equivocal lymph nodes on MRI characterized as negative. PET-positive nodal status at diagnosis was found to be a statistically significant predictor of relapse-free survival (p < 0.05).

CONCLUSION

Staging FDG PET-CT has a major impact on the initial management of approximately one-third of patients with LACC by altering treatment intent and/or radiotherapy planning. PET-defined nodal status is a poor prognostic indicator.

Gynecologic tumors: how to communicate imaging results to the surgeon

Gynecologic cancers are a leading cause of morbidity and mortality for female patients, with an estimated 88,750 new cancer cases and 29,520 deaths in the United States in 2012. To offer the best treatment options to patients it is important that the radiologist, surgeon, radiation oncologist, and gynecologic oncologist work together with a multidisciplinary approach. Using the available diagnostic imaging modalities, the radiologist must give appropriate information to the surgeon in order to plan the best surgical approach and its timing.

The role of PET/CT in the management of cervical cancer

OBJECTIVE. Cervical cancer is the second most common malignancy in women worldwide and the third most common cause of cancer mortality in the United States. The aim of this article is to describe cervical cancer and outline the value of (18)F-FDG PET/CT in the management of cervical malignancy. CONCLUSION. The value of PET/CT has been found in staging and treatment strategy for cervical cancer. FDG PET/CT facilitates decision-making and radiation treatment planning and provides important information about treatment response, disease recurrence, and long-term survival.

Intracardiac metastasis from known cervical cancer: a case report and literature review

Cardiac metastasis from known cervical cancer is rare. Even through a routine check-up, this type of metastasis can present as pulmonary emboli. Suspicion of this diagnosis in an oncology patient with complicating pulmonary emboli but no evidence of deep vein thrombosis is important, especially in cervical cancer patients with extensive pelvic lymph node metastasis and vascular invasion of a primary tumor. Early recognition may aid in improving the prognosis. We present a case of intracardiac metastasis arising from a squamous carcinoma of the cervix in a patient with pulmonary tumor emboli and review other cases from the literature.

Correlation between biological marker expression and F-fluorodeoxyglucose uptake in cervical cancer measured by positron emission tomography

BACKGROUND

This study aimed to determine whether several biologic markers were associated with (18)fluorine-fluorodeoxyglucose ((18)F-FDG) uptake in patients with carcinoma of the cervix.

PATIENTS AND METHODS

60 patients with International Federation of Gynecology and Obstetrics (FIGO) stages IA2 to IIB cervical cancer, who underwent (18)FDG positron emission tomography/computed tomography (PET/CT), were included in the current study. All patients underwent radical hysterectomy. Tumor sections were stained by immunohistochemistry for glucose transporter 1 (GLUT1), carbonic anhydrase-IX (CA-IX), vascular endothelial growth factor (VEGF), hexokinase type I (HK-I), hexokinase type II (HK-II), and cytoplasmic and nuclear hypoxia-inducible factor (HIF) 1α.

RESULTS

The expression of GLUT1 (p = 0.005), VEGF (p = 0.021), HK-II (p = 0.009), and cytoplasmic HIF1α (p = 0.024) was significantly associated with a higher median standardized uptake value (SUVmax). There was a positive correlation between (18)F-FDG uptake and GLUT1 (p = 0.008), CA-IX (p = 0.030), HK-II (p < 0.001) as well as cytoplasmic HIF1α (p = 0.016), whereas this relationship was not observed among the VEGF, HK-I and nuclear HIF1α.

CONCLUSION

The data presented in this study indicate that (18)F-FDG uptake is associated with the presence of GLUT1, VEGF, nuclear HK-II, and cytoplasmic HIF1α. There was also a significant correlation among the rate of expression of GLUT1, HK-II, cytoplasmic HIF1α, and CAIX in carcinomas of the cervix.

Clinical impact of ¹⁸F-FDG PET/CT in the pretreatment evaluation of patients with locally advanced cervical carcinoma

AIM

The aim of this study was to evaluate the impact of F-fluorodeoxyglucose (F-FDG) PET/computed tomography (CT) on the pretreatment evaluation of patients with locally advanced cervical carcinoma.

METHOD

Forty-seven patients with stage 2b-4a cervical carcinoma underwent F-FDG PET/CT for initial staging and pretreatment evaluation. Concomitant pelvic/abdominal MRI was performed in 38 patients. The contribution of PET/CT to treatment planning was evaluated, and the prognostic performance of PET/CT was compared with that of MRI. Lymph node (LN) status on PET/CT was correlated with patient follow-up data.

RESULTS

PET/CT detected hypermetabolic LNs in 39/47 patients. In 24/39 patients (62%), PET/CT was found to be superior to MRI. In 13/24 patients (54%), PET/CT detected para-aortic ± pelvic LNs, which were not found on MRI. PET/CT successfully detected distant metastases in 10 patients and peritonitis carcinomatosa in one patient; these patients were upstaged clinically. Overall, PET/CT has led to modifications in the extent of the radiotherapy field in 34% of patients and to major alterations in treatment plans in 23% of patients with widespread disease. The frequency of PET-positive LNs was significantly lower in patients who were alive without disease at the time of last follow-up (60%) compared with patients with persistent disease and nonsurvivors (100%, P=0.012).

CONCLUSION

The presence of PET-positive LNs has prognostic significance in patients with cervical carcinoma. PET/CT has the potential to show both lymphatic and distant metastases, which results in modifications to the chemoradiotherapeutic regimen. The use of PET/CT must be included in the initial workup of patients with locally advanced cervical carcinoma.

Biological predictors of cervical cancer response to radiation therapy

The addition of cisplatin-based chemotherapy to standard radiation therapy reduces the risk of recurrence and disease-related death rates from locally advanced cervical cancers by as much as 50%. However, the absolute gains are relatively small for patients with early tumors, many of whom would have been cured with radiation alone, and recurrence rates are still high for patients who have very large or advanced-stage tumors. As a result, there is a pressing need for more accurate predictors of radiocurability. A variety of types of biomarkers have been shown to correlate with cervical cancer response to radiation therapy. These include traditional clinical and morphologic predictors, non-molecular biomarkers, including hypoxia and fluorodeoxyglucose-positron emission tomography (FDG-PET) avidity, as well as molecular biomarkers, which include single-gene markers or array-based multigene predictors. Multi-gene predictors of response remain immature in cervical cancer, but studies thus far have paved the way for future studies to validate these findings. Methods will need to be standardized and markers will need to be validated on homogeneous patient populations and treatment approaches before they can become useful tools for clinical decision making. In addition, new biomarkers will be of major value only if they add to the predictive value of traditional clinical and morphologic predictors. Ultimately, the most useful biomarkers will identify patients who will benefit from specific molecularly targeted agents in addition to radiation therapy or perhaps identify patient who are at low risk for recurrence, for whom the dose of radiation or chemotherapy can be reduced.

Variable uterine uptake of FDG in adenomyosis during concurrent chemoradiation therapy for cervical cancer

To avoid improper tumor volume contouring in radiation therapy (RT) and other invasive procedures, we report a case of uterine adenomyosis showing increased ¹⁸F-fluorodeoxyglucose (FDG) uptake on positron emission tomography (PET)/computed tomography (CT) mimicking malignant tumor in a 44-year-old woman during concurrent chemoradiation therapy (CCRT) for uterine cervical cancer. The adenomyosis was not associated with her menstrual cycle or with normal endometrium uptake, and it resolved one month after completion of RT. This case indicates that uterine adenomyosis in a premenopausal woman may show false positive uptake of ¹⁸FDG-PET/CT associated with CCRT.

PET/CT in gynecologic cancer: present applications and future prospects--a clinician's perspective

This article briefly reviews the epidemiology, diagnosis, and treatment of the common gynecologic malignancies, with an emphasis on the shortcomings of current clinical practice. The persistent need to achieve early diagnosis, adjust proper treatment, enhance surveillance, and improve the outcome of these patients has led to the development of new diagnostic modalities. Novel tools such as 18F-fluorodeoxyglucose PET/CT should aim at enhancing the clinician's ability to make critical decisions in treating difficult scenarios.

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.

Molecular imaging in oncology: the acceptance of PET/CT and the emergence of MR/PET imaging

In the last decade, PET-only systems have been phased out and replaced with PET-CT systems. This merger of a functional and anatomical imaging modality turned out to be extremely useful in clinical practice. Currently, PET-CT is a major diagnostic tool in oncology. At the dawn of the merger of MRI and PET, another breakthrough in clinical imaging is expected. The combination of these imaging modalities is challenging, but has particular features such as imaging biological processes at the same time in specific body locations.