Standardized uptake value in para-aortic lymph nodes is a significant prognostic factor in patients with primary advanced squamous cervical cancer

FDG PET-CT as an important diagnostic tool and prognostic marker in suspected recurrent cervical carcinoma after radiotherapy: comparison with MRI

BACKGROUND

Recurrent disease in post-irradiation patients with cervical cancer is often difficult to delineate on magnetic resonance imaging (MRI), because posttreatment changes can have a similar appearance, and further evaluation is often required. The aims of the study were to evaluate positron emission tomography/computed tomography with 18F-fluorodeoxyglucose (FDG PET-CT) diagnostic role in suspected recurrent cervical cancer after radiotherapy, compare it to MRI, and assess their prognostic impact in these patients.

PATIENTS AND METHODS

This cohort retrospective study included patients previously treated with radiotherapy for carcinoma of uterine cervix with suspected recurrence, who had undergone MRI of abdomen and pelvis, and were subsequently evaluated on FDG PET-CT, with minimum follow-up period of 12 months.

RESULTS

In the total of 84 patients included in analysis, MRI vs. FDG PET-CT showed sensitivity, specificity and accuracy of 80.1%, 52.4% and 66.7%, vs. 97.6%, 61.9% and 79.8%, respectively. Patients with positive findings on MRI (Log Rank, p = 0.003) and PET-CT (Log Rank, p < 0.001) had shorter progression-free survival (PFS) than those with negative results. In univariate Cox regression models, MRI and FDG PET-CT results were found to be related to PFS (p = 0.005 and p < 0.001, respectively). However, multivariate analysis proved only FDG PET-CT to be independent prognostic factor, where patients with positive FDG PET-CT results had almost nine times higher risk of progression (p < 0.001).

CONCLUSION

FDG PET-CT represents useful diagnostic tool in suspected recurrent cervical cancer after radiotherapy, showing high sensitivity in its detection. In addition, it is an independent factor in predicting progression-free survival in these 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

Interest of para-aortic lymphadenectomy for locally advanced cervical cancer in the era of PET scanning

BACKGROUND AND OBJECTIVES

Treatment of locally advanced cervical cancer (LACC) involves pelvic chemoradiotherapy, using an extended field in the case of para-aortic involvement. 18-Fluoro-D-glucose positron emission tomography combined with computer tomography (PET-CT) is an accurate method for the detection of metastatic nodes. The objective of this study was to evaluate the performance of PET-CT for lymph node staging of LACC.

METHODS

This bicentric retrospective study included patients with LACC who had a PET-CT scan followed by para-aortic lymphadenectomy between January 2015 and December 2019. Based on pathological findings, sensitivity, specificity, negative predictive value (NPV), positive predictive value (PPV) and false-negative (FN) rates of PET-CT for para-aortic node involvement were evaluated.

RESULTS

Seventy-one patients who had undergone laparoscopic lymphadenectomy were included in this study. The intraoperative complication rate was 2.8%. Sensitivity, specificity, NPV and PPV for PET-CT were 55% [95% confidence interval (CI) 44.6-67.1], 84% (95% CI 75-92), 93% (95% CI 87-99) and 33% (95% CI 22-44), respectively. FN rates in the case of negative or positive pelvic PET-CT were 5.7% and 9.5%, respectively.

CONCLUSIONS

Para-aortic lymphadenectomy is recommended for lymph node staging in the case of negative para-aortic PET-CT. In view of the low FN rate of PET-CT, surgical staging should be discussed regardless of pelvic status if the patient presents high surgical risk, or if this delays the commencement of chemoradiotherapy.

A Unique Finding of Hepatogastric Fistula in Cervical Cancer Liver Metastasis

In India, cervical cancer is the second leading cause of cancer-related mortality among females. Around one-third are expected to develop recurrence or metastasis during follow-up. Liver metastasis is rarely requiring palliative treatment. Patient compliance to strict follow-up is vital to detect early metastasis to be able to improve survival. A 58-year-old lady (International Federation of Gynecology and Obstetrics [FIGO] stage IIIB) was treated with concurrent chemoradiotherapy. During follow-up, she had complained of abdominal pain for which cross-sectional imaging revealed a left lobe liver lesion fistulizing into the stomach. Liver metastasis fistulizing into the stomach is a rarity, and a biopsy is required to confirm metastasis or maybe a second primary. Although palliation in the form of chemotherapy is the standard, minor or major hepatectomy can be considered in patients with good performance status at high-volume centers. A tailored multidisciplinary team approach is required for better survival.

18F-FDG PET/computed tomography scan in patients with suspicion of recurrent neuroendocrine carcinoma of the cervix

OBJECTIVES

The aim of this study was to investigate the value of [18F]fluoro-2-deoxy-D-glucose (18F-FDG) PET/computed tomography (CT) to detect recurrent cervical neuroendocrine carcinoma and its subsequent impact on patient management.

METHODS

A total of 25 patients who had undergone 30 18F-FDG PET/CT studies for suspected recurrent cervical neuroendocrine carcinoma (18 small cells, 2 large cells, 1 atypical carcinoid, and 4 unclassified) were retrospectively analyzed. The findings of the PET/CT images were compared with the histopathologic results in 8 scans and with clinical follow-up in 22 scans.

RESULTS

Of the 30 PET/CT studies, 63.3% (19/30) were positive for recurrence while 36.7% (11/30) were negative. The sensitivity, specificity, positive predictive value, negative predictive value, and accuracy of 18F-FDG PET/CT for detecting recurrent disease of cervical neuroendocrine carcinomas were 90.0, 90.0, 94.7, 81.8, and 90.0%, respectively. Metastasis to distant organs was the most common (89.4%), followed by lymph node recurrence (52.6%). Lungs were the most frequent site of distant metastasis (63.1%). 18F-FDG PET/CT findings led to the change of the management in 10 out of 25 patients (40%) by introducing the use of previously unplanned therapeutic procedures.

CONCLUSIONS

18F-FDG PET/CT is an efficient technique for detecting recurrent cervical neuroendocrine carcinoma, and may thus contribute to improving patient management.

18F-FDG PET/CT Identifies Predictors of Survival in Patients with Locally Advanced Cervical Carcinoma and Paraaortic Lymph Node Involvement to Allow Intensification of Treatment

Our objective was to use ¹⁸F-FDG PET/CT to identify a high-risk subgroup requiring therapeutic intensification among patients with locally advanced cervical cancer (LACC) and paraaortic lymph node (PALN) involvement. Methods: In this retrospective multicentric study, patients with LACC and PALN involvement concurrently treated with chemoradiotherapy and extended-field radiotherapy between 2006 and 2016 were included. A senior nuclear medicine specialist in PET for gynecologic oncology reviewed all ¹⁸F-FDG PET/CT scans. Metabolic parameters including SUV_max, metabolic tumor volume, and total lesion glycolysis (TLG) were determined for the primary tumor, pelvic lymph nodes, and PALNs. Associations between these parameters and overall survival (OS) were assessed with the Cox proportional hazards model. Results: Sixty-eight patients were enrolled in the study. Three-year OS was 55.5% (95% confidence interval, 40.8-68.0). When adjusted for age, stage, and histology, pelvic lymph node TLG, PALN TLG, and PALN SUV_max were significantly associated with OS (P < 0.005). Conclusion: ¹⁸F-FDG PET/CT was able to identify predictors of survival in the homogeneous subgroup of patients with LACC and PALN involvement, thus allowing therapeutic intensification to be proposed.

The efficacy of pretreatment and after treatment 18F-FDG PET/CT metabolic parameters in patients with locally advanced squamous cell cervical cancer

OBJECTIVES

Cervical cancer is one of the main causes of cancer death worldwide. Fluorine-18-fluorodeoxyglucose (F-FDG) PET/computed tomography (PET/CT) has been playing an increasingly important role in staging and monitoring treatment response in the disease. In the current study, we investigated metabolic F-FDG PET/CT parameters among patients with locally advanced squamous cell cervical cancer treated with concurrent chemoradiotherapy for predicting disease-free survival (DFS).

PATIENTS AND METHODS

Forty-four patients with biopsy-proven locally advanced squamous cell cervical cancer were included in the study. Pretreatment and after treatment F-FDG PET/CT metabolic parameters [metabolic tumor volume, tumor lesion glycolysis, maximum standard uptake value (SUVmax)] for the primary tumor area and/or pelvic/para-aortic lymph nodes and also accompanying distant metastases were analyzed. Treatment response was divided into four groups according to a post-treatment F-FDG PET/CT scan.

RESULTS

For all patients, the 3-year DFS was 79%. Pretreatment primary tumor SUVmax and tumor lesion glycolysis, pelvic lymph node SUVmax, and pretreatment para-aortic lymph node SUVmax were significant prognostic factors for DFS with different cut-off values. In contrast, for metabolic tumor volume-T1, there was no statistical significance for DFS.

CONCLUSION

F-FDG PET/CT cut-off values may help clinicians with their treatment planning and follow-up in locally advanced squamous cell cervical cancer patients.

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 significance of metabolic tumor volume and total lesion glycolysis in patients with advanced cervical carcinoma

AIM

18-Fluoro-2-deoxy-d-glucose positron emission tomography (¹⁸F-FDG PET/CT) is considered to be the most accurate image method of detection of node or distant metastases in cervical cancer. Metabolic tumor volume (MTV) and total lesion glycolysis (TLG) of ¹⁸F-FDG PET/CT are volumetric measurements of tumor cells with increased ¹⁸F-FDG uptake. The prognostic value of MTV and TLG in patients with advanced cervical cancer (ACC) were evaluated.

METHODS

38 patients with ACC from one tertiary university hospital underwent ¹⁸F-FDG PET/CT between June 2009 and December 2015. Clinicopathologic factors and various PET parameters were analyzed to evaluate their relationship with recurrence-free survival (RFS) and overall survival (OS). These parameters were: maximum standardized uptake value (SUVmax), mean standardized uptake value (SUV mean), metabolic tumor volume (MTV), and total lesion glycolysis (TLG) of the primary tumor, of the pelvic nodes, of the paraaortic nodes and the metabolic volume of the metastases if any.

RESULTS

A total of 38 patients with ACC fulfilled the inclusion criteria. All of them underwent a ¹⁸F-FDG PET/CT before definitive chemoradiotherapy. In the univariate analyses higher tumor size, pelvic lymph node metastasis and both MTV and TLG showed a significant association with OS and with RFS (MTV HR=1.55, p=0.011 and TLG HR=1.43, p=0.017 for RFS and MTV HR=1.82, p=0.006 and TLG HR=1.67, p=0.007 for OS).

CONCLUSION

Pretreatment TLG sum and MTV sum seem to be independent prognostic factors for OS and RFS in patients with advanced cervical cancer treated with definitive chemoradiotherapy and they are better than the classic measurement of SUVmax.

(18F)-FDG PET/CT parameters to predict survival and recurrence in patients with locally advanced cervical cancer treated with chemoradiotherapy

PURPOSE

To identify predictive (¹⁸F)-fluorodeoxyglucose (FDG) positron emission tomography (PET)/computed tomography (CT)-based parameters for locoregional control, disease-free survival and overall survival, by testing different thresholds of metabolic tumor volume and total lesion glycolysis in patients with locally-advanced cervical cancer.

PATIENTS AND METHODS

Thirty-seven patients treated with standard chemoirradiation underwent a pretreatment (¹⁸F)-FDG-PET/CT. Using different thresholds of maximum standardized uptake value, the following PET parameters were computed: maximum standardized uptake value, mean standardized uptake value, metabolic tumor volume and total lesion glycolysis for primary tumor and lymph nodes and a new parameter combining the metabolic tumor volume and the distance between lymph nodes and the primary tumor, namely metabolic node distance. Correlation between PET and clinical parameters with clinical outcome (overall survival, disease-free survival, and locoregional control) was assessed using univariate and multivariate analyses (Cox model).

RESULTS

In univariate analyses, PET/CT parameters associated with overall survival and disease-free survival were: metabolic tumor volume and total lesion glycolysis of the primary tumor, total lesion glycolysis of lymph nodes and metabolic node distance. The most predictive threshold segmentation for metabolic tumor volume and total lesion glycolysis was 48% of maximum standardized uptake value for the primary tumor and 30% for the lymph nodes. In multivariate Cox analysis, the total lesion glycolysis of primary tumor 48% and metabolic node distance were the two independent risk factors for overall survival (P<0.01), disease-free survival (P<0.01) and locoregional control (P=0.046).

CONCLUSION

Total lesion glycolysis of primary tumor and distance between the invaded positive lymph node and the primary tumor seem to have the highest predictive value when compared to classical clinical prognostic parameters and may be useful to identify high risk groups at time of diagnosis and to tailor the therapeutic approach in locally-advanced cervical cancer.

Prognostic value of total lesion glycolysis measured by 18F-FDG PET/CT in patients with locally advanced cervical cancer

AIM

The aim of this study was to determine the most relevant parameters of fluorine-18 fluorodeoxyglucose (F-FDG) PET/computed tomography (CT) for predicting recurrence in patients with locally advanced cervical cancer.

MATERIALS AND METHODS

Fifty-six patients diagnosed with International Federation of Gynecology and Obstetrics (FIGO) stage IIB to IVA cervical cancer who underwent F-FDG PET/CT before definitive chemoradiotherapy were retrospectively enrolled. Various PET parameters, namely, maximum standardized uptake value, mean standardized uptake value, metabolic tumor volume, and total lesion glycolysis (TLG) of the primary tumor, were analyzed to evaluate the relationship between these PET parameters and recurrence-free survival (RFS). The cut-off values of PET parameters that showed the best trade-off between sensitivity and specificity for RFS were determined by receiver operating characteristic curve analysis.

RESULTS

The median follow-up was 20 months (range, 6-63 months). Univariate analysis indicated that higher FIGO stage [hazard ratio (HR) 5.606, 95% confidence interval (CI) 1.682-18.68, P=0.005], metabolic tumor volume more than 47.81 cm (HR 6.203, 95% CI 1.351-28.481, P=0.019), and TLG more than 215.02 (HR 11.817, 95% CI 1.518-91.963, P=0.018) were associated with RFS. In multivariate analysis, FIGO stage (HR 4.618, 95% CI 1.295-16.463, P=0.018) and TLG more than 215.02 (HR 10.171, 95% CI 1.246-83.044, P=0.030) were independent predictive factors for RFS. Kaplan-Meier curves for RFS indicated that patients with TLG less than or equal to 215.02 showed better RFS (P=0.003).

CONCLUSION

Pretreatment TLG proved to be an independent prognostic factor for RFS in patients with locally advanced cervical cancer treated by definitive chemoradiotherapy.

Advances in diagnosis and treatment of metastatic cervical cancer

Cervical cancer is one of the most common cancers in women worldwide. The outcome of patients with metastatic cervical cancer is poor. We reviewed the relevant literature concerning the treatment and diagnosis of metastatic cervical cancer. There are two types of metastasis related to different treatments and survival rates: hematogenous metastasis and lymphatic metastasis. Patients with hematogenous metastasis have a higher risk of death than those with lymphatic metastasis. In terms of diagnosis, fluoro-2-deoxy-D-glucose positron emission tomography (FDG-PET) and PET-computed tomography are effective tools for the evaluation of distant metastasis. Concurrent chemoradiotherapy and subsequent chemotherapy are well-tolerated and efficient for lymphatic metastasis. As for lung metastasis, chemotherapy and/or surgery are valuable treatments for resistant, recurrent metastatic cervical cancer and chemoradiotherapy may be the optimal choice for stage IVB cervical cancer. Chemotherapy and bone irradiation are promising for bone metastasis. A better survival is achieved with multimodal therapy. Craniotomy or stereotactic radiosurgery is an optimal choice combined with radiotherapy for solitary brain metastases. Chemotherapy and palliative brain radiation may be considered for multiple brain metastases and other organ metastases.

(18)F-FDG PET in small-cell cervical cancer: a prospective study with long-term follow-up

PURPOSE

Small-cell cervical cancer (SCCC) is rare and prone to metastasize. We conducted a prospective study to evaluate the role of (18)F-FDG PET in the management of this aggressive malignancy.

METHODS

Patients with untreated primary, histologically confirmed SCCC were enrolled. (18)F-FDG PET (or PET/CT) was performed immediately after MRI or CT, for primary staging, monitoring response to treatment or restaging when there was suspicion of recurrence. The clinical impact of PET was determined on a scan basis.

RESULTS

A total of 25 patients were recruited and 43 PET scans were performed. The PET images were obtained for primary staging (25 patients), monitoring response (10 patients) and restaging when there was suspicion of recurrence (8 patients). The median follow-up time in event-free patients was 109.3 months (range 97.5 - 157.7 months). A positive impact of PET was found in 8 (18.6 %) of the 43 scans, which included detection of additional regions of distal lymph node (LN) metastasis (one primary staging scan, two restaging scans), bone metastasis (two primary staging scans, one monitoring response scan), and exclusion of false-positive lesions on MRI (one primary staging scan, one restaging scan). On the other hand, one negative impact was recorded as one false-positive lesion on a restaging PET scan. One positive impact was noted for monitoring response (bone metastasis). The impact of three scans was indeterminate. The positive impact of down-staging in avoiding overtreatment but finding additional distal LN (except one on restaging) or bone metastases had no beneficial effect on long-term survival.

CONCLUSION

The results of this preliminary study suggest that PET is useful in the management of SCCC. PET could have more value in detecting occult metastases if future novel therapies are able to offer better control of extensive SCCC.

Prognostic Value of the Sum of Metabolic Tumor Volume of Primary Tumor and Lymph Nodes Using 18F-FDG PET/CT in Patients With Cervical Cancer

This is an observational study to determine the most relevant parameter of ¹⁸F-fluorodeoxyglucose (FDG) positron emission tomography/computed tomography (PET/CT) for predicting recurrence in cervical cancer. Fifty-six patients with International Federation of Gynecology and Obstetrics (FIGO) stage IIB-IVA cervical cancer who underwent pretreatment ¹⁸F-FDG PET/CT were enrolled. PET parameters including maximum standardized uptake value (SUVmax), metabolic tumor volume (MTV), and total lesion glycolysis (TLG) of both primary tumor and pelvic and/or para-aortic lymph nodes were analyzed. SUVmax-S was defined as the sum of the SUVmax of primary tumor and the higher SUVmax of either pelvic or para-aortic lymph nodes. MTV-S was defined as the sum of the MTV of primary tumor and pelvic and para-aortic lymph nodes. TLG-S was calculated in the same way as MTV-S. We evaluated the relationship between these PET parameters and recurrence-free survival (RFS). Univariate analysis revealed that higher FIGO stage (hazard ratio [HR] = 5.61, 95% confidence interval [CI]: 1.68-18.68, P = 0.005), lymph node metastasis (HR = 3.42, 95% CI: 1.08-10.84, P = 0.037), MTV of primary tumor >47.81 cm³ (HR = 6.20, 95% CI: 1.35-28.48, P = 0.019), TLG of primary tumor >215.02 (HR = 11.82, 95% CI: 1.52-91.96, P = 0.018), MTV-S > 59.01 cm³ (HR = 8.24, 95% CI: 1.80-37.77, P = 0.007), and TLG-S > 224.15 (HR =  13.09, 95% CI: 1.68-101.89, P = 0.014) were associated with RFS. In multivariate analysis, FIGO stage (HR = 4.87, 95% CI: 1.38-17.18, P = 0.014) and MTV-S > 59.01 cm³ (HR = 7.37, 95% CI: 1.54-35.16, P = 0.012) were determined to be independent predictive factors for RFS. Our preliminary results reveal that MTV-S is an independent prognostic factor for RFS in patients with cervical cancer treated by definitive chemoradiotherapy.

Comparison of the Prognostic Value of F-18 Pet Metabolic Parameters of Primary Tumors and Regional Lymph Nodes in Patients with Locally Advanced Cervical Cancer Who Are Treated with Concurrent Chemoradiotherapy

Objective

This study investigated the metabolic parameters of primary tumors and regional lymph nodes, as measured by pre-treatment F-18 fluorodeoxyglucose positron emission tomography/computed tomography (F-18 FDG PET/CT) to compare the prognostic value for the prediction of tumor recurrence. This study also identified the most powerful parameter in patients with locally advanced cervical cancer treated with concurrent chemoradiotherapy.

Methods

Fifty-six patients who were diagnosed with cervical cancer with pelvic and/or paraaortic lymph node metastasis were enrolled in this study. Metabolic parameters including the maximum standardized uptake value (SUVmax), the metabolic tumor volume (MTV), and total lesion glycolysis (TLG) of the primary tumors and lymph nodes were measured by pre-treatment F-18 FDG PET/CT. Univariate and multivariate analyses for disease-free survival (DFS) were performed using the clinical and metabolic parameters.

Results

The metabolic parameters of the primary tumors were not associated with DFS. However, DFS was significantly longer in patients with low values of nodal metabolic parameters than in those with high values of nodal metabolic parameters. A univariate analysis revealed that nodal metabolic parameters (SUVmax, MTV and TLG), paraaortic lymph node metastasis, and post-treatment response correlated significantly with DFS. Among these parameters, nodal SUVmax (hazard ratio [HR], 4.158; 95% confidence interval [CI], 1.1–22.7; p = 0.041) and post-treatment response (HR, 7.162; 95% CI, 1.5–11.3; p = 0.007) were found to be determinants of DFS according to a multivariate analysis. Only nodal SUVmax was an independent pre-treatment prognostic factor for DFS, and the optimal cutoff for nodal SUVmax to predict progression was 4.7.

Conclusion

Nodal SUVmax according to pre-treatment F-18 FDG PET/CT may be a prognostic biomarker for the prediction of disease recurrence in patients with locally advanced cervical cancer.

Gynecologic oncologic imaging with PET/CT

FDG-PET/CT has been evaluated in a variety of gynecologic malignancies in a variety of settings and is approved by the Centers for Medicare & Medicaid Services for the initial and subsequent treatment strategies of these malignancies. Cervical cancer is typically very FDG avid, and FDG-PET/CT appears to be most valuable for initial staging, radiation therapy planning, and detection of recurrent disease. For ovarian cancer, the most value of FDG-PET/CT appears to be for detecting recurrent disease in the setting of rising CA-125 level and negative or equivocal anatomical imaging studies. Initial studies evaluating response to therapy are promising and further work in this area is needed. FDG uptake in both nonmalignant and physiological processes in the pelvis can make interpretation of FDG-PET/CT in this region challenging and knowledge of these entities and patterns can avoid misinterpretation. Some of the most common findings relate to the cyclic changes that occur as part of the menstrual cycle in premenopausal women. Mucinous tumors and low-volume or peritoneal carcinomatosis are causes of false-negative results on FDG-PET/CT studies. As new tracers are developed, comparisons with patient outcomes and standards of care (eg, FDG-PET/CT) will be needed.

Prognostic value of 18F-fluorodeoxyglucose uptake in pelvic lymph nodes in patients with cervical cancer treated with definitive chemoradiotherapy

PURPOSE

To evaluate the prognostic significance of the maximum standardized uptake (SUVmax) value for pelvic lymph nodes in patients with cervical cancer and its impact on treatment response, disease control, and survival.

METHODS

Ninety-three patients with pelvic or para-aortic metastasis detected by PET/CT and treated with definitive chemoradiotherapy were evaluated. The impact of pelvic lymph node SUVmax on prognostic factors and treatment outcomes was assessed.

RESULTS

The size and SUVmax of pelvic lymph nodes were significantly correlated (r=0.859; p<0.001). Patients with pelvic and para-aortic lymph node metastases had significantly higher SUVmax values for both primary tumor (23.4±9.2 vs. 18.5±7.3; p=0.01) and pelvic lymph nodes (11.4±4.6 vs. 7.4±3.8; p=0.001). Patients with pelvic lymph node SUVmax≥7.5 had significantly higher primary tumor SUVmax, larger pelvic lymph nodes, higher rates of para-aortic lymph node metastasis, and lower post-therapy complete response rates. Overall survival (OS) and disease-free survival (DFS) rates were significantly higher in patients with SUVmax<7.5 compared to patients with SUVmax≥7.5. In a multivariate analysis, pelvic lymph node SUVmax and post-therapy metabolic response were significant prognostic factors for both OS and DFS for all patients, but no significant prognostic factors were found in pelvic lymph node metastasis only.

CONCLUSIONS

Patients with highly FDG-avid pelvic lymph nodes have a higher risk of disease recurrence with worse survival. Identification of these patients may assist in the evaluation of the clinical benefits of additional treatments.

A randomized trial comparing concurrent chemoradiotherapy with single-agent cisplatin versus cisplatin plus gemcitabine in patients with advanced cervical cancer: An Asian Gynecologic Oncology Group study

OBJECTIVE

A recent randomized trial demonstrated that concurrent chemoradiotherapy (CCRT) with weekly cisplatin and gemcitabine, followed by two adjuvant cycles of cisplatin and gemcitabine improved survival for advanced cervical cancer patients. An Asian Gynecologic Oncology Group (AGOG) study was designed to determine whether only adding gemcitabine in the chemoradiation phase without adjuvant chemotherapy could improve survival.

METHODS

Between March 2009 and March 2013, 74 eligible patients with International Federation of Obstetrics and Gynecology stage III/IVA cervical cancer or stage I/II with positive pelvic/para-aortic nodal metastasis were enrolled. Thirty-seven patients were randomized to arm C (weekly cisplatin 40mg/m(2)) and 37 patients were randomized to arm CG (weekly cisplatin 40mg/m(2) and gemcitabine 125mg/m(2)), for six cycles. Six eligible patients were excluded before the beginning of treatment.

RESULTS

An interim analysis showed superimposable progression-free (PFS) and overall survival (OS), a decision of closing accrual was made. A 3-year PFS was similar in both arms (arm C 65.1% vs. arm CG 71.0%, p=0.71), and a 3-year OS was 74.1% in arm C vs. 85.9% in arm CG (p=0.89), but crossed over at 5years. Grade 2-4 hematological toxicities, including neutropenia (p=0.028) and thrombocytopenia (p=0.001), were more frequent in arm CG than arm C.

CONCLUSIONS

Despite limitation in power, it suggests that only adding gemcitabine at the CCRT phase does not provide substantially superior results, but treatment toxicities could increase. Further studies are required to determine the role of post-CCRT adjuvant chemotherapy in advanced cervical cancer.

Preoperative PET/CT FDG standardized uptake value of pelvic lymph nodes as a significant prognostic factor in patients with uterine cervical cancer

PURPOSE

Using integrated PET/CT, we evaluated the prognostic relevance in uterine cervical cancer of preoperative pelvic lymph node (LN) [(18)F]FDG uptake.

METHODS

Patients with FIGO stage IB to IIA uterine cervical cancer were imaged with FDG PET/CT before radical surgery. We used Cox proportional hazards regression to examine the relationship between recurrence and the FDG maximum standardized uptake value (SUV(max)) in the pelvic LN (SUVLN) on PET/CT.

RESULTS

Clinical data, treatment modalities, and results in 130 eligible patients were reviewed. The median postsurgical follow-up was 34 months (range 6 to 109 months). Receiver operating characteristic analysis identified SUVLN 2.36 as the most significant cut-off value for predicting recurrence. SUV(LN) was correlated with SUV(tumour) (P = 0.002), primary tumour size (P = 0.004), and parametrial invasion (P = 0.013). Univariate analyses showed significant associations between recurrence and SUV(LN) (P = 0.001), SUV(tumour) (P = 0.007), pelvic LN metastasis (P = 0.002), parametrial invasion (P < 0.001), primary tumour size (P = 0.007), suspected LN metastasis on MRI (P = 0.024), and FIGO stage (P = 0.026). Multivariate analysis identified SUV(LN) (P = 0.013, hazard ratio, HR, 4.447, 95 % confidence interval, CI, 1.379 – 14.343) and parametrial invasion (P = 0.013, HR 6.728, 95 % CI 1.497 – 30.235) as independent risk factors for recurrence. Patients with SUV(LN) ≥ 2.36 and SUV(LN) <2.36 differed significantly in terms of recurrence (HR 15.20, P < 0.001).

CONCLUSION

Preoperative pelvic LN FDG uptake showed a strong significant association with uterine cervical cancer recurrence.

Molecular imaging in the management of cervical cancer

Positron emission tomography (PET), magnetic resonance imaging (MRI), and integrated 18-fluorodeoxyglucose ((18)F-FDG) PET/computed tomography are valuable techniques for assessing prognosis, treatment response after the completion of concurrent chemoradiation, suspicious or documented recurrence, unexplained post therapy elevations in tumor markers, and the response to salvage treatment when managing cervical cancer. However, PET plays a limited role in the primary staging of MRI-defined node-negative patients. Currently, (18)F-FDG is still the only tracer approved for routine use, but several novel targeting PET compounds, high-Tesla MRI machines, diffusion-weighted imaging without contrast, and dynamic nuclear polarized-enhanced (13)C-MR spectroscopic imaging may hold promising applications.

Staging of uterine cervical carcinoma: whole-body diffusion-weighted magnetic resonance imaging

PURPOSE

To evaluate the clinical value of magnetic resonance whole-body diffusion-weighted imaging (WB-DWI) in the staging of uterine cervical carcinoma.

MATERIALS AND METHODS

Twenty-six patients with untreated uterine cervical carcinoma received preoperative conventional MR and WB-DWI scans. WB-DWI scans were also obtained in 30 healthy volunteers. Measurements of apparent diffusion coefficient (ADC) were made on scans of normal uterine cervix and uterine cervical carcinoma, and benign and metastatic lymph nodes. Statistical analysis was applied to the obtained data.

RESULTS

Mean ADC value of uterine cervical carcinoma was significantly lower than the 3 layers of normal uterine cervix (P = 0.00). When an ADC value of 1.28 × 10(-3) mm(2)/s is used as the threshold, its sensitivity is 96%, specificity is 100%, and accuracy is 98%. Mean ADC value of metastatic nodes [(0.96 ± 0.14) × 10(-3) mm(2)/s] was significantly lower than that of benign nodes [(1.39 ± 0.19) × 10(-3) mm(2)/s] (t = 9.93, P = 0.00). When an ADC value of 1.14 × 10(-3) mm(2)/s is used as the threshold, its sensitivity is 83%, specificity is 98%, and accuracy is 94%.

CONCLUSION

WB-DWI scan is capable of distinguishing uterine cervical carcinoma from normal uterine cervix, and is capable of separating metastatic nodes from benign nodes.

¹⁸F-fluoro-2-deoxyglucose uptake on PET CT and glucose transporter 1 expression in colorectal adenocarcinoma

AIM

To evaluate the correlation between the level of (18)F-fluoro-2-deoxyglucose ((18)F-FDG) uptake and glucose transporter 1 (GLUT1) expression in colorectal adenocarcinoma (CRA).

METHODS

Forty four patients with resected CRA and preoperative (18)F-FDG positron emission tomography - computed tomography data were investigated in this study. Comparison of maximum standardized uptake value (SUVmax) of the lesion was made with GLUT1 expression by immunohistochemistry and various clinicopathologic factors including tumor volume, invasion depth, gross finding, and lymph node metastasis.

RESULTS

SUVmax was 14.45 ± 7.0 in negative GLUT1 expression cases, 15.51 ± 5.7 in weak GLUT1 expression cases, and 16.52 ± 6.8 in strong GLUT1 expression cases, and there was no correlation between between GLUT1 expression and SUVmax. SUVmax was significantly correlated with tumor volume (P < 0.001). However, there was no significant differences in SUVmax and GLUT1 expression among other clinicopathologic factors.

CONCLUSION

GLUT1 expression does not correlates significantly with (18)F-FDG uptake in CRA. (18)F-FDG uptake was increased with tumor volume, which is statistically significant.

[((18)F)-fluorodeoxyglucose PET/CT in cervix cancer: lymph node assessment and prognostic/predictive value of primary tumour analysis]

PURPOSE

In cervix carcinoma: (a) to evaluate the ability of ((18)F)-fluorodeoxyglucose (FDG) positron emission tomography (PET) in the lymph node detection; (b) to investigate the prognostic and predictive value of the primary cervical PET parameters.

PATIENTS AND METHODS

Ninety patients treated for cervix carcinoma and evaluated initially by MRI and FGD PET were included. The performances of FDG-PET for lymph node detection (relatively to the lymph node dissection) have been described (sensitivity, specificity, positive predictive value and negative predictive value). PET tumour parameters analyzed were: maximum standard uptake value (SUVmax), the volume and the maximum diameter. The prognostic and predictive values of these parameters were investigated. The tumour response was evaluated on surgical specimens.

RESULTS

PET detected the cervical tumour with a sensitivity of 97% (mean values: SUVmax=15.8, volume=27 mm(3), maximum diameter=47). For the detection of the lymph nodes, the values of sensibility, specificity, positive predictive value and negative predictive value were: 86, 56, 69 and 78% in the pelvic, and 90, 67, 50 and 95% for the para-aortic area, respectively. The SUVmax was correlated with histologic response (P=0.04). The frequency of partial histological response was significantly higher for tumour SUVmax>10.9 (P=0.017). The maximum PET diameter and pathologic response had an impact on disease-free survival and overall survival in multivariate analysis (P<0.05).

CONCLUSION

PET has high sensitivity in detecting pelvic and para-aortic lymph nodes. Some primary cervical tumour PET parameters are useful as prognostic and predictive factors.

Prognostic impact of standardized uptake value of F-18 FDG PET/CT in nasopharyngeal carcinoma

PURPOSE

We evaluated the use of metabolic parameters of F-18 fluorodeoxyglucose positron emission tomography (FDG PET) for the assessment of the primary tumor and nodal metastasis in predicting survival in nasopharyngeal carcinoma (NPC) patients.

MATERIALS AND METHODS

The F-18 FDG PET/CT (computed tomography) scans of 46 consecutive newly diagnosed NPC patients were retrospectively reviewed. Maximal standardized uptake value (SUVmax) corrected for lean body mass of primary tumor (pSUVmax) and highest SUVmax of cervical lymph nodes (nSUVmax) were recorded. The association of FDG uptake and 2-year disease-free survival (DFS) was examined.

RESULTS

Significantly better DFS was found in patients with pSUVmax <7.5 and nSUVmax <6.5 (P = 0.042 and P = 0.019, respectively). In multivariate analysis, both pSUVmax and nSUVmax were significant independent predictors of DFS.

CONCLUSIONS

The SUVmax of the primary tumor and nodal metastasis are useful parameters for predicting DFS in NPC patients.

Identification of prognostic factors in patients with cervical cancer and supraclavicular lymph node recurrence

OBJECTIVE

Patients with cervical cancer and supraclavicular lymph nodes (SLN) recurrence have a poor but heterogeneous prognosis. The aim of this study was to identify potential prognostic factors - including FDG-PET results - that may affect survival and treatment outcomes in patients with this group of patients.

METHODS

Between January 2001 and December 2008, we identified a total of 31 consecutive patients with cervical cancer who had evidence of SLN recurrence. All participants underwent FDG-PET. Survival was measured from the date of documented SLN recurrence. The latency period was defined as the length of time from the date of first diagnosis to the date of SLN recurrence.

RESULTS

The median follow-up time was 22.8 months (range: 4.7-105.1). The 3- and 5-year survival rates were 41% and 27.3%, respectively. Patients with intermediate SUV values (between 4.3 and 8) had a significantly better prognosis than subjects with both high (>8) or low (<4.3) SUV values (p=0.004). Latency period <2 years, SCC-Ag levels ≥ 4ng/mL, recurrence extend beyond SLN, and SUV of <4.3 >8 were significant adverse prognostic factors by multivariate analysis. The 3-year overall survival (OS) rate of patients carrying 0-1 adverse prognostic factors was 90% (low-risk group), while 3-year OS rates for intermediate-risk group (2 factors) and high-risk group (3-4 factors) were 30% and 0%, respectively (p=0.001).

CONCLUSION

Our results justify the use of PET (accurate extent of relapse and SUV) as a prognostic tool in patients with cervical cancer and SLN recurrence.

Restricted water diffusibility as measured by diffusion-weighted MR imaging and choline uptake in (11)C-choline PET/CT are correlated in pelvic lymph nodes in patients with prostate cancer

PURPOSE

(11)C-Choline-positron emission tomography (PET)/computed tomography (CT) is increasingly used in patients with prostate cancer. Another promising technique for assessment of tumor biology is diffusion-weighted MR imaging (DWI). The aim of the study was to compare the functional parameters standardized uptake value (SUV) in PET and apparent diffusion coefficient (ADC) value in DWI of lymph nodes in prostate cancer patients.

PROCEDURES

Fourteen patients with prostate cancer underwent DWI at 1.5T and (11)C-Choline-PET/CT. ADC values and SUVs of all lymph nodes larger than 5 mm (n = 55) were compared by using linear regression analysis. Performance of DWI and (11)C-Choline PET was assessed by receiver operator characteristic curve analysis using histopathology or clinical follow-up as standard of reference.

RESULTS

ADC values and SUV showed a moderate but highly significant inverse correlation (r = -0.5144, p < 0.0001). In lymph nodes with low ADC values, the dispersion of SUV was more pronounced. Moreover, a highly significant difference was observed for mean ADC values and SUV in lymph nodes considered as benign or malignant by follow-up/histopathology (ADC 1.60 ± 0.24 vs. 1.09 ± 0.23 × 10(-3) mm(2)/s; SUV 1.82 ± 0.57 vs. 4.68 ± 03.12; p < 0.0001, respectively).

CONCLUSION

These pilot data propose the ADC value in DWI as a new potential imaging biomarker which might provide additional information on tumor pathophysiology compared to the SUV in (11)C-Choline PET/CT.

Established, emerging and future applications of FDG-PET/CT in the uterine cancer

Integrated positron emission tomography/computed tomography (PET/CT) with 2-[¹⁸F]fluoro-2-deoxy-D-glucose (FDG) is a useful technique to acquire both glucose metabolic and anatomic imaging data using a single device in a single diagnostic session and has opened a new field in clinical oncologic imaging. FDG-PET/CT has been used successfully for the staging, optimization of treatment, re-staging, therapy monitoring, and prognostic prediction of uterine cervical cancer and endometrial cancer as well as various malignant tumours. The present review discusses the current role of FDG-PET/CT in the management of uterine cancer, discussing its usefulness and limitations in the imaging of these patients.

Spectrum of FDG PET/CT findings of uterine tumors

OBJECTIVE

The purpose of this article is to review FDG PET/CT and MRI findings in a variety of benign and malignant tumors of the uterus and to become familiar with the wide variety of FDG PET/CT findings of this entity.

CONCLUSION

Benign uterine tumors generally have mild FDG uptake, and leiomyoma rarely shows high uptake. Uterine malignant tumors generally have intense FDG uptake, whereas malignant uterine tumors that are small or that have low cellular density often show minimal uptake.

Pelvic lymph node F-18 fluorodeoxyglucose uptake as a prognostic biomarker in newly diagnosed patients with locally advanced cervical cancer

BACKGROUND

The objective of the current study was to evaluate the prognostic significance of the maximum standardized uptake value (SUV(max)) of F-18 fluorodeoxyglucose (FDG) as measured by positron emission tomography (PET) in pelvic lymph nodes in patients with cervical cancer.

METHODS

The authors studied cervical cancer patients with pelvic lymph node metastasis, as evidenced on FDG-PET, who were treated between November 2003 and October 2008. The maximum dimension and SUV(max) for the most FDG-avid pelvic lymph node (SUV(PLN)) and the SUV(max) of the primary cervical tumor (SUV(cervix)) were recorded from the FDG-PET/computed tomography (CT) scan. The SUV(PLN) was analyzed for its association with treatment response, pelvic disease recurrence, disease-specific survival, and overall survival.

RESULTS

The population was comprised of 83 women with International Federation of Gynecology and Obstetrics (FIGO) stages IB1 to IIIB cervical cancer. The average SUV(PLN) was 6.9 (range, 2.1-33.0), whereas the average SUV(cervix) was 14.0 (range, 3.2-38.4). The SUV(cervix) and SUV(PLN) were found to be weakly correlated (correlation coefficient [R(2)] = 0.301). The average size of the pelvic lymph nodes was 2.1 cm (range, 0.6-7.9 cm), and was also found to be only weakly associated with the SUV(PLN) (R(2) = 0.225). The SUV(PLN) was found to be correlated with an increased risk of persistent disease after treatment (P = .0025), specifically within the pelvic lymph node region (P = .0003). The SUV(PLN) was found to be predictive of an increased risk of ever developing pelvic disease recurrence (P = .0035). Patients with a higher SUV(PLN) were found to have significantly worse disease-specific (P = .0230) and overall survival (P = .0378) using Kaplan-Meier evaluation. A Cox proportional hazards model for the risk of pelvic disease recurrence was performed including SUV(PLN,) patient age, and tumor stage, and found only an increased SUV(PLN) to be an independent predictor.

CONCLUSIONS

SUV(PLN) is a prognostic biomarker, predicting treatment response, pelvic recurrence risk, and disease-specific survival in patients with cervical cancer.

[Prognostic value of pretherapeutic 18F-FDG PET/CT in cancer of the uterine cervix: a retrospective study of 53 patients]

OBJECTIVES

Assessment of prognostic value of pretherapeutic (18)F-FDG PET/CT (PET).

PATIENTS AND METHODS

Retrospective study of 53 patients with invasive uterine cervix carcinoma. Each patient has been evaluated with pretherapeutic whole-body FDG PET/CT and pelvic MRI. Minimal follow-up lasted for 1 year. On PET/CT, we have visually analyzed metabolism of primary tumor, pelvic and para-aortic lymph nodes in comparison with surrounding structures. We have compared prognostic factors as pretherapeutic haemoglobin rate, FIGO staging, MRI and PET/CT data using Mann-Whitney univariate analysis and Cox multivariate analysis.

RESULTS

Para-aortic lymph node abnormal uptake on PET/CT was the only independent predictor of progression-free survival. Pelvic lymph node involvement on PET/CT was the only independent predictor of overall survival. MRI did not provide any additional information.

DISCUSSION AND CONCLUSION

Lymph node involvement visually assessed by (18)F-FDG PET/CT was the most significant prognostic factor for overall and progression-free survival.

[Positron emission tomography in the management of cervix cancer patients]

Since its introduction in clinical practice in the 1990's, positron emission tomography (PET), usually with (18)F-fluoro-2-deoxy-D-glucose ((18)F-FDG), has become an important imaging modality in patients with cancer. For cervix carcinoma, FDG-PET is significantly more accurate than computed tomography (CT) and is recommended for loco-regional lymph node and extrapelvic staging. The metabolic dimension of the technique provides additional prognostic information. Ongoing studies now concentrate on more advanced clinical applications, such as the planning of radiotherapy, the response evaluation after the induction of therapy, the early detection of recurrence. Technical innovations, such as PET cameras with better spatial resolution and hybrid positron emission tomography/computed tomography (PET-CT), available now on the whole territory, provide both anatomic and metabolic information in the same procedure. From the point of view of biological metabolism, new radiopharmaceutical probes are being developed. Those hold promise for future refinements in this field. This article reviews the current applications of FDG-PET in patients with cervix cancer.

Correlation of apparent diffusion coefficients measured by 3T diffusion-weighted MRI and SUV from FDG PET/CT in primary cervical cancer

PURPOSE

Diffusion-weighted magnetic resonance imaging (DWI) and fluorodeoxyglucose positron emission tomography/computed tomography (FDG PET/CT) are oncological feasible techniques. Currently, apparent diffusion coefficient (ADC) measured by DWI and standard uptake value (SUV) from FDG PET/CT have similar applications in clinical oncology. The aim of this study was to assess the correlation between ADC and SUV in primary cervical cancer.

MATERIALS AND METHODS

Patients with documented primary cervical cancer were recruited. All participants underwent abdominopelvic DWI at 3T and FDG PET/CT within 2 weeks. For the primary tumor, ADC was measured as minimum ADC (ADC(min)) and mean ADC (ADC(mean)) within the whole tumor by DWI. Maximum SUV (SUV(max)) and mean SUV (SUV(mean)) were measured by FDG PET/CT.

RESULTS

A total of 33 patients were included. There was no significant correlation either between ADC(min) and SUV(max) or between ADC(mean) and SUV(mean). The relative ADC(min) (rADC(min)) defined as ADC(min)/ADC(mean) ratio was significantly inversely correlated with the relative SUV(max) (rSUV(max)) defined as SUV(max)/SUV(mean) ratio (r = -0.526, P = 0.0017) in all study patients. A significantly inverse correlation between rADC(min) and rSUV(max) was observed in patients with adenocarcinoma/adenosquamous carcinoma (r = -0.685, P = 0.0012) and those with well-to-moderate differentiated tumor (r = -0.631, P = 0.0050). No significant correlation was demonstrated in patients with squamous cell carcinoma or poorly differentiated tumor.

CONCLUSIONS

The significantly inverse correlation between rADC(min) and rSUV(max) in primary cervical tumor suggests that DWI and FDG PET/CT might play a complementary role for the clinical assessment of this cancer type.