Paola Mapelli

Use of [11C]Choline PET-CT as a Noninvasive Method for Detecting Pelvic Lymph Node Status from Prostate Cancer and Relationship with Choline Kinase Expression

Purpose: To evaluate the accuracy and biological basis for [11C]choline-PET-CT in the nodal staging of high risk localized prostate cancer patients. Experimental Design: Twenty-eight patients underwent dynamic [11C]choline-PET-CT of the pelvis and lower abdomen prior to extended laparoscopic pelvic lymph node dissection (eLPL). The sensitivity and specificity of [11C]choline PET, [11C]choline PET-CT, and MRI for nodal detection were calculated. Average and maximal standardized uptake values (SUVave, SUVmax) were compared with choline kinase alpha (CHKα) and Ki67 immunohistochemistry scores. Results: Four hundred and six lymph nodes (LN), in 26 patients, were assessable. Twenty-seven (6.7%) involved pelvic nodes at eLPL were detected in 9 patients. Seventeen of the 27 involved nodes were subcentimeter. The sensitivity and specificity on a per nodal basis were 18.5% and 98.7%, 40.7% and 98.4%, and 51.9% and 98.4% for MRI, [11C]choline PET, and [11C]choline PET-CT, respectively. Sensitivity was higher for [11C]choline PET-CT compared with MRI (P = 0.007). A higher nodal detection rate, including subcentimeter nodes, was seen with [11C]choline PET-CT than MRI. Malignant lesions showed CHKα expression in both cytoplasm and nucleus. SUVave and SUVmax strongly correlated with CHKα staining intensity (r = 0.68, P < 0.0001 and r = 0.63, P = 0.0004, respectively). In contrast, Ki67 expression was generally low in all tumors. Conclusion: This study establishes the relationship between [11C]choline PET-CT uptake with choline kinase expression in prostate cancer and allows it to be used as a noninvasive means of staging pelvic LNs, being highly specific and more sensitive than MRI, including the detection of subcentimeter disease. Clin Cancer Res; 17(24); 7673–83. ©2011 AACR.

[11C]Choline Positron Emission Tomography/Computerized Tomography for Early Detection of Prostate Cancer Recurrence in Patients with Low Increasing Prostate Specific Antigen

PURPOSE The effectiveness of salvage therapy in prostate cancer is greater for low prostate specific antigen values. Therefore, early detection of tumor recurrence is warranted. [(11)C]choline positron emission tomography/computerized tomography has the potential of early restaging of prostate cancer with low prostate specific antigen, but the selection of patients at high risk for positive [(11)C]choline positron emission tomography/computerized tomography is desirable to optimize salvage therapy. MATERIALS AND METHODS This retrospective study included 75 patients with prostate cancer with an increasing prostate specific antigen less than 1.5 ng/ml after radical prostatectomy who never received antiandrogen deprivation therapy or salvage radiotherapy who underwent [(11)C]choline positron emission tomography/computerized tomography for the restaging of disease. Binary logistic regression was used to assess predictive factors of positive [(11)C]choline positron emission tomography/computerized tomography. Included variables were trigger prostate specific antigen, prostate specific antigen doubling time, age, pathological stage and Gleason score. RESULTS Median prostate specific antigen was 0.61 ng/ml. [(11)C]choline positron emission tomography/computerized tomography was positive in 16 of 75 patients (21%). On univariate analysis prostate specific antigen doubling time less than 6 months was the only factor significantly associated with an increased risk of positive [(11)C]choline positron emission tomography/computerized tomography (OR 7.77, 95% CI 2.34-25.80, p = 0.001). In patients with prostate specific antigen doubling time less than 6 months, the positive detection rate of [(11)C]choline positron emission tomography/computerized tomography increased to 50%. CONCLUSIONS In patients with prostate cancer with biochemical failure after radical prostatectomy and prostate specific antigen less than 1.5 ng/ml, prostate specific antigen doubling time less than 6 months predicts positive [(11)C]choline positron emission tomography/computerized tomography. In these patients [(11)C]choline positron emission tomography/computerized tomography may reduce by 50% the number in whom salvage therapy is initiated empirically without knowing the disease location.

Incidental finding of parathyroid adenoma with 11C-choline PET/CT.

Positron emission tomography/computed tomography (PET/CT) with 11C-choline is an established diagnostic tool for restaging prostate cancer patients with biochemical failure after primary treatment. In the present case, 11C-choline PET/CT was performed in a prostate cancer patient with skeletal metastases, treated with hormonal therapy. In addition to the detection of pathologic uptake at prostate and vertebra, 11C-choline uptake occurred in the neck. The finding was suggestive for a parathyroid adenoma on subsequent ultrasound, then finally confirmed by parathyroid scintigraphy and histopathological analysis performed after hemithyroidectomy.

High-grade endometrial cancer: value of [18F]FDG PET/CT in preoperative staging

ObjectiveThe purpose of this study was to assess the value of 2-[18F]fluoro-2-deoxy-D-glucose positron emission tomography/computed tomography ([18F]FDG PET/CT) in the primary staging of high-risk endometrial cancer patients. MethodsThis retrospective study was conducted on 32 consecutive patients with histological diagnosis of primary high-risk endometrial cancer, who underwent PET/CT with [18F]FDG in addition to conventional clinical and instrumental staging procedures. After surgery, [18F]FDG PET/CT findings were correlated with pathological findings on a patient-by-patient basis. The diagnostic accuracy of [18F]FDG PET/CT for primary cancer detection, lymph nodal involvement and distant metastases was assessed. Results[18F]FDG PET/CT could correctly detect primary tumor in 29 of the 32 high-risk patients, with a sensitivity of 90.6%. The overall [18F]FDG PET/CT patient-based sensitivity, specificity, positive predictive value, negative predictive value and accuracy were 57.1, 100.0, 100.0, 86.4, and 88.5%, respectively, for revealing lymph nodal neoplastic involvement, and 100.0, 96.0, 87.5, 100.0, 96.9%, respectively, for detecting distant metastases. In particular, while the suspicion of distant metastases was documented by conventional imaging in only two patients, [18F]FDG PET/CT correctly identified metastatic lesions in seven patients (21.9% of cases). ConclusionThe major benefit provided in high-grade tumor patients by the use of [18F]FDG PET/CT in the primary staging of endometrial cancer is its ability to accurately detect distant metastases in the abdomen and extra-abdominal regions. [18F]FDG PET/CT adds relevant information that may influence patient management.

Radiation Treatment of Lymph Node Recurrence from Prostate Cancer: Is 11C-Choline PET/CT Predictive of Survival Outcomes?

PET/CT is a valuable tool to detect lymph node (LN) metastases in patients with biochemical failure after primary treatment for prostate cancer (PCa). The aim was to assess the predictive role of imaging parameters derived by 11C-choline PET/CT on survival outcomes—overall survival, locoregional relapse-free survival, clinical relapse-free survival (cRFS), and biochemical relapse-free survival (bRFS)—in patients treated with helical tomotherapy (HTT) for LN recurrence. Methods: This retrospective study included 68 patients affected by PCa (mean age, 68 y; age range, 51–81 y) with biochemical recurrence after primary treatment (median prostate-specific antigen values obtained at the time of PET/CT scan, 2.42 ng/mL; range, 0.61–27.56 ng/mL) who underwent 11C-choline PET/CT from January 2005 to January 2013 and were treated with HTT in correspondence of the pathologic choline LN uptake. PET-derived parameters, including maximum/mean standardized uptake value (SUVmax and SUVmean, respectively) and metabolic tumor volume (MTV) with a threshold of 40%, 50%, and 60% were calculated. The best cutoff values of PET-derived parameters discriminating between patients with and without relapse, after treatment guided by PET, were assessed by receiver-operating-characteristic (ROC) curve analysis. Univariate and multivariate Cox regression analysis including the most predictive PET-derived parameters and survival outcomes were performed. Results: The median follow-up was 20 mo (mean, 26 mo; range, 3–97 mo). 11C-choline PET/CT showed pathologic LN uptake in 4 patients at the pelvic level, in 5 at the abdominal level, in 13 at both the pelvic and the abdominal level, and in 46 at the abdominal or pelvic or other sites. The 2-y overall survival, locoregional relapse-free survival, cRFS, and bRFS were 87%, 91%, 51%, and 40%, respectively. On the basis of ROC curves, the most discriminative cutoff value for MTV values was an MTV threshold of 60% (MTV60) of greater than 0.64 cm3. No significant cutoff values were found for SUVmax or SUVmean at univariate analysis, whereas MTV60 was confirmed as an independent predictor in multivariate analysis and significantly correlated with bRFS and cRFS. MTV60 and extrapelvic disease well predict the risk of cRFS. Conclusion: 11C-choline PET/CT performed as a guide for HTT on LN recurrence is predictive of survival. In particular, MTV60 and extrapelvic disease were the best predictors of tumor response for bRFS and cRFS in PCa patients with LN recurrence after primary treatment. This information may be useful in emerging treatment strategies.

Initial prostate cancer diagnosis and disease staging--the role of choline-PET-CT.

An early and correct diagnosis together with accurate staging of prostate cancer is necessary in order to plan the most appropriate treatment strategy. Morphological imaging modalities such as transrectal ultrasonography (TRUS), CT, and MRI can have some limitations regarding their accuracy for primary diagnosis and staging of prostate cancer; for instance, they have limited specificity in differentiating cancer from benign prostatic conditions and, by using size as the only criterion to characterize lymph node metastases, they might not be accurate enough for tumour characterization. In this scenario, PET–CT with 11C-labelled or 18F-labelled choline derivatives provides morphological and functional characterization and could overcome the limitations of the conventional imaging techniques. PET–CT is one of the most investigated molecular imaging modalities for prostate cancer diagnosis and staging. Currently, the main investigations on the role of PET–CT in the diagnosis and staging of prostate cancer have been performed on a retrospective basis and this type of analysis might be one of the main reasons why different results regarding its diagnostic accuracy have been reported.

Erdheim-Chester disease: imaging-guided therapeutic approach.

Erdheim-Chester disease (ECD) is a rare form of systemic non-Langerhans cell histiocytosis with characteristic bone involvement. However, extraskeletal involvement occurs in approximately half of the patients. Because of its protean findings, the diagnosis of ECD is often delayed; thus, a clinical suspicion may prompt specific imaging studies to recognize suggestive signs of organ involvement. In this study, a case of a patient with ECD with representative progressive multisystemic involvement has been reported; although the final diagnosis was confirmed by histologic analysis, imaging studies with almost pathognomonic findings guided the diagnostic process and prompted different therapeutic approaches according to the localization of the disease.

Evaluation of prostate cancer with 11C-Choline PET/CT for treatment planning, response assessment, and prognosis

The aim of this review is to report on the value of 11C-choline PET imaging as a diagnostic procedure for metastasis-directed therapies. Furthermore, the role of 11C-choline PET/CT as a diagnostic tool for monitoring castration-resistant prostate cancer patients treated with systematic therapy is assessed. Finally, the role of 11C-choline PET/CT in the prediction of survival in both castration-resistant prostate cancer patients and hormone-naïve patients is investigated.

11C- or 18F-Choline PET/CT for Imaging Evaluation of Biochemical Recurrence of Prostate Cancer

Recurrence of prostate cancer is suspected when an increase in the prostate-specific antigen level is detected after radical treatment; the recurrence could be local relapse, distant relapse, or both. Differentiation between the two patterns of relapse is critical for choosing the proper treatment strategy. Choline PET/CT could be of help in discriminating patients with local, lymph node, and bone recurrences, thus having an impact on patient management.

PET/MRI and prostate cancer

AbstractAdvances in medical imaging are needed to support the general goal of personalized patient-centric care. This is particularly true for prostate cancer, which frequently presents as the initial multifocal disease with variable significance and outcome, and, when aggressive, can recur after the initial definitive management. The combined simultaneous acquisition of multi-parametric magnetic resonance imaging and positron emission tomography (PET) can provide combined structural, metabolic, and functional imaging information regarding prostate cancer status in a whole-body single session examination. As described in this review article, combining PET and MRI appears particularly useful for pelvic disease assessments, as PET and MRI provide complementary information, which can be best obtained with hybrid PET/MR scanners. While there is growing interest in the field of prostate cancer imaging regarding the value of PET/MRI, the current literature in this field is sparse and insufficient for a systematic analysis. This article, therefore, highlights available evidence and future perspectives of PET/MRI for the initial diagnosis, staging, and restaging of prostate cancer with choline-based radiotracers as well as ligands to target prostate-specific membrane antigen.