Choline PET Scan Research Articles

Prognostic value of C-11 choline PET/CT scan in patients with metastatic castration resistant prostate cancer (m-CRPC) undergoing treatment with radium-223.

59 Background: Radium-223 (Ra-223) has been approved for the treatment of metastatic castration resistant prostate cancer (mCRPC) with predominantly osseous metastases. PSA flare phenomenon with Ra-223 limits the use of PSA as a prognostic tool to predict treatment response. Currently, there is a lack of diagnostic tools to predict treatment response to Ra-223. Therefore, we sought to investigate the role of mid-treatment C-11 choline PET/CT scan in predicting overall response to Ra-223. Methods: In a single institute retrospective study, we identified 32 patients who were treated with a full course of 4-6 cycles of Ra-223 and were evaluated with both PSA and C-11 choline PET scan before treatment, at mid-treatment, and after a complete course of Ra-223 between 2013 – 2018. Ra-223 was used as salvage therapy for their predominant bone disease after failing chemotherapy and 2nd generation hormone therapy. Blind repeat radiographic evaluation of patients’ scans was performed by a radiologist specialized in nuclear radiology. Favorable response was defined by achieving partial response or stable disease on imaging, while unfavorable response was defined by showing progressive disease on imaging. Results: Mean age (±SD) at starting Radium223 was 67.6 (±7.1) years, median (IQR) primary Gleason score was 9 (8-9), and median (IQR) pretreatment PSA was 13.5 (5.4-39.6) ng/ml. 78% of the patients (n=25) completed 6 cycles of Ra-223, 15% of the patients (n=5) completed 5 cycles, and 6% (n=2) received only 4 cycles. At mid-treatment scanning, 25% of the patients (n=8) showed favorable response (Group A), while 75% of the patients (n=24) showed unfavorable response (B). After a complete course of treatment, 62.5% of patients (n=5) in Group (A) continued to show favorable response, while only 8.3% of patients (n=2) in Group (B) showed favorable response (p-value= 0.0023). Conclusions: Mid-treatment evaluation with C-11 choline PET/CT scan can predict overall response to Radium 223. Patients with progressive disease at mid-treatment evaluation are very likely not going to respond to further treatment. Further studies and clinical trials are warranted.

Salvage Radiotherapy for Macroscopic Local Recurrence Following Radical Prostatectomy.

IntroductionSalvage radiotherapy is the only curative treatment for biochemical progression after radical prostatectomy. Macroscopic recurrence may be found in the prostatic bed. The purpose of our study is to evaluate the effectiveness of salvage radiotherapy of the prostate bed with a boost to the area of the macroscopic recurrence.Material and MethodsFrom January 2005 to January 2020, 89 patients with macroscopic recurrence in the prostatectomy bed were treated with salvage radiotherapy +/- hormone therapy. The average PSA level prior to radiotherapy was 1.1 ng/mL (SD: 1.6). At the time of biochemical progression, 96% of the patients had a MRI that revealed the macroscopic recurrence, and 58% had an additional choline PET scan. 67.4% of the patients got a boost to the macroscopic nodule, while 32.5% of the patients only underwent radiotherapy of the prostate bed without a boost. The median total dose of radiotherapy was 70 Gy (Min.: 60 – Max.: 74). The most commonly-used regimen was radiotherapy of the prostatectomy bed with a concomitant boost. 48% of the patients were concomitantly treated with hormone therapy.ResultsAfter a median follow-up of 53.7 months, 77 patients were alive and 12 had died, of which 4 following metastatic progression. The 5-year and 8-year survival rates (CI95%) are, respectively, 90.2% (78.9-95.6%) and 69.8% (46.4-84.4%). The 5-year biochemical progression-free survival rate (CI95%) is 50.8% (36.7-63.3). Metastatic recurrence occurred in 11.2% of the patients. We did not find any statistically significant impact from the various known prognostic factors for biochemical progression-free survival. No toxicity with a grade of > or = to 3 was found.ConclusionsOur series is one of the largest published to date. Salvage radiotherapy has its place in the management of patients with biochemical progression with local recurrence in the prostate bed, with an acceptable toxicity profile. The interest of the boost is to be evaluated in prospective trials.

INNOVATE (NRG-GU008): A randomized phase III trial of salvage radiotherapy and androgen deprivation therapy (ADT) with/without abiraterone and apalutamide for patients with node-positive prostate cancer after radical prostatectomy.

TPS179 Background: Node-positive prostate cancer comprises for approximately 13% of newly-diagnosed patients and represents an aggressive form of the disease, but has been historically understudied in therapeutic clinical trials. Cure rates remain suboptimal for these patients with early stage IV disease, so clinical trials to intensify systemic treatment are warranted. Abiraterone and apalutamide have each demonstrated efficacy in improving metastasis-free survival and/or overall survival in the advanced stage setting, including both castrate-resistant and metastatic castration-sensitive prostate cancer. The mechanisms of action of abiraterone and apalutamide are complementary, and combination therapy has been shown in a prior Phase Ib trial to be safe and well-tolerated. Methods: Patients with pathologic node-positive disease by radical prostatectomy and who subsequently have a detectable PSA are eligible for this randomized controlled trial. All patients are required to receive molecular imaging (FACBC, PSMA, or choline PET scan) at trial entry and must have no radiographic evidence of distant metastasis in order to remain eligible. Eligible patients are randomized 1:1 to (control arm) salvage radiation therapy with 2 years of ADT vs (experimental arm) addition of 2 years of abiraterone/prednisone and apalutamide. The primary endpoint is metastasis-free survival. With a sample size of 586 and with a potential for 10% loss to follow-up, the trial has 90% power with one-sided alpha=0.025 to detect a HR of 0.53 for the experimental arm vs control arm for the primary endpoint. Secondary endpoints include quality of life (EPIC-26, EQ5D-5L, Brief Pain Inventory, PROMIS-Fatigue), overall survival, time to castrate resistance, and other disease-related outcomes. In addition, data will be collected to validate the Decipher score and PAM50-based classification as predictive biomarkers in this node-positive patient population. Trial was activated on March 5, 2020, and is currently enrolling patients. This project was supported by grants U10CA180868 (NRG Oncology Operations), U10CA180822 (NRG Oncology SDMC), U24CA196067 (NRG Oncology Specimen Bank) from the National Cancer Institute (NCI) and Janssen and GenomeDX. Clinical trial information: NCT04134260.

The French experience of PSMA PET for the diagnosis of biological recurrence of prostate cancer

PSMA PET can only be performed in France in the context of a temporary authorization for use (ATU) granted by the ANSM only in the event of biological recurrence of prostate cancers with a normal or equivocal Fucyclovine or Choline PET scan. We present the experience of the Léon Bérard cancer centre and report on the experience of 3 other French centres that have published their results obtained within the framework of this ATU. Despite the absence of histological comparison of our results, the evidence of suspicious lesions on PSMA PET examination may induce changes in patient management in almost 2/3 of the patients. This is consistent with the already abundant results in the literature, which show a clear superiority of PSMA PET over Choline PET for the diagnosis of biological recurrence of prostate cancer.

Does Using Choline PET Scans in Patients with Prostate Cancer Alter Management? A South Wales Experience

Does Using Choline PET Scans in Patients with Prostate Cancer Alter Management? A South Wales Experience

Utility of 11C choline PET CT and MRI in relapsed prostate cancer (PC).

e16586 Background: Choline intracellular transport is upregulated in PC, and it is phosphorylated by choline kinase and becomes trapped within PC cells. 11 C Choline has t½ life of 20.4 minutes and emits positrons detectable by PET. Retrospective studies of 11 C choline PET CT in (PC) have been reported. In this original prospective study, we calculated the performance of 11C choline with whole body PET CT and pelvic PET MRI in patients (pts) with biochemical PC relapse. Methods: From November 2014- June 2016, 101 pts with biochemical PC relapse underwent 11C choline PET CT and pelvic PET MRI. Scans were read in blinded fashion. Tissue was obtained from area of 11 C Choline positivity and correlated with scan results. Results: Sixty-two pts (61%) were included in the analysis. 49 pts were excluded due to non-compliance with protocol. 11C choline PET CT and pelvic MRI showed a sensitivity of 92.5%, specificity of 45.5%, positive predictive value of 75.5%, and negative predictive value of 76.9%. Of 37 pts with positive 11C choline PET scans and confirmation of PC, 12 (32%) had positive 11C choline PET scans and negative CT and MRI scans; 7 (18%) had positive C11 choline and CT scans and negative MRI scans; 12 (32%) had positive 11C choline and MRI scans and negative CT scans, and 9 (24%) had positive 11C choline, CT and MRI scans. Mean PSA level in this group of 37 pts was 9.86 ng/mL (range 0.4 – 107.9 ng/mL), and 7 (19%) of the pts had PSA levels < 2 ng/mL. Conclusions: 11C choline PET improves detection of relapsed PC over CT and MRI scans. 11C choline PET pelvic MRI improves detection over 11C choline PET CT.

Multimodal image and mapping guided focal salvage high-dose-rate brachytherapy for local recurrent prostate cancer.

122 Background: Image guided brachytherapy and mapping biopsy could reduce the toxicity of the total salvage brachytherapy. This study evaluate the tumor control and the tolerance of a focal real time salvage high-dose-rate (HDR) brachytherapy to treat the local relapse as defined on transperineal mapping biopsy, multipara-metric MRI and Choline PETSCAN on the same treatment planning. Methods: Between October 2013 and June 2016, Twenty-nine patients with local relapse on Choline PET Scan after a primary irradiation had a salvage HDR Brachytherapy (2 fractions of 10 Gy within 4-6 hours in one implant) without hormone. One month before brachytherapy All patients had real time transperineal randomized European regions standardised magnetic resonance imaging (MRI) prostate biopsies and targeted biopsies with a fusion of T2 MRI sequence /CholinePETscan (50 % SUV) to intraoperative transrectal ultrasound one month before brachytherapy. We used Flex Focus 400 ultrasound machine BK, Vitesse 3.0 and 3 D navigation with EXII Stepper in order to use the result of mapping biopsy for real time HDR brachytherapy treatment planning study. Tumor control was measure with phoenix definition and Kaplan-Meier. The GU and GI toxicity were measure with CTCAE V 3. Results: 13 Low risk, 10 Intermediate risk, 8 High risk, initially treated with 3 Iodine brachytherapy ( 160 GY), 15 EBRT ≥ 78 Gy and 7 EBRT ≤ 70 gy were include. The number of biopsy (mean volume, 21 cm3; SD, 6.7). Prostate Volume (mean volume, 29.7 cm3; SD, 12.5). CTV Volume (mean volume, 13.3 cm3; SD, 6.7). Mean dose to 90% of the prostate was 11.4 Gy (SD, 1.45). Mean dose to 90% of the CTV was 21.1 Gy (SD, 1.45). Mean dose to 90% of the CTVmri was 27.6 Gy (SD, 3.4). The biologic disease free survival at 2 years is 65 % (Kaplan-Meier). Disease without hormone survival at 2 years is 86,5%. The chronic toxicity ( > 6 mois) was 6 Gu and 4 GI for grade ≤ 2 and 1 GU grade 3 (total incontinence). Conclusions: Focal, mapping and multimodal image guided salvage HDR brachytherapy for recurrent prostate cancer is a feasible therapy. This approach has to be evaluated in multicenter cohort.

Response Detection of Castrate-Resistant Prostate Cancer to Clinically Utilised and Novel Treatments by Monitoring Phospholipid Metabolism.

Androgen receptor (AR) activation is the primary driving factor in prostate cancer which is initially responsive to castration but then becomes resistant (castration-resistant prostate cancer (CRPC)). CRPC cells still retain the functioning AR which can be targeted by other therapies. A recent promising development is the use of inhibitors (Epi-1) of protein-protein interaction to inhibit AR-activated signalling. Translating novel therapies into the clinic requires sensitive early response indicators. Here potential response markers are explored. Growth inhibition of prostate cancer cells with flutamide, paclitaxel, and Epi-1 was measured using the MTT assay. To simulate choline-PET scans, pulse-chase experiments were carried out with [3H-methyl]choline and proportion of phosphorylated activity was determined after treatment with growth inhibitory concentrations of each drug. Extracts from treated cells were also subject to 31P-NMR spectroscopy. Cells treated with flutamide demonstrated decreased [3H-methyl]choline phosphorylation, whilst the proportion of phosphorylated [3H-methyl]choline that was present in the lipid fraction was increased in Epi-1-treated cells. Phospholipid breakdown products, glycerophosphorylcholine and glycerophosphoethanolamine levels, were shown by 31P-NMR spectroscopy to be decreased to undetectable levels in cells treated with Epi-1. LNCaP cells responding to treatment with novel protein-protein interaction inhibitors suggest that 31P-NMR spectroscopy may be useful in detecting response to this promising therapy.

MP57-02 IS THERE A ROLE FOR CHOLINE PET SCANNING IN SALVAGE PROSTATECTOMY?

You have accessJournal of UrologyProstate Cancer: Localized: Surgical Therapy III1 Apr 2016MP57-02 IS THERE A ROLE FOR CHOLINE PET SCANNING IN SALVAGE PROSTATECTOMY? Sanchia Goonewardene, Gideon Bletcher, Rick Catterwell, Declan Cahill, Raj Persad, David Gillatt, Ben Challacombe, Prokar Dasgupta, and Rick Popert Sanchia GoonewardeneSanchia Goonewardene More articles by this author , Gideon BletcherGideon Bletcher More articles by this author , Rick CatterwellRick Catterwell More articles by this author , Declan CahillDeclan Cahill More articles by this author , Raj PersadRaj Persad More articles by this author , David GillattDavid Gillatt More articles by this author , Ben ChallacombeBen Challacombe More articles by this author , Prokar DasguptaProkar Dasgupta More articles by this author , and Rick PopertRick Popert More articles by this author View All Author Informationhttps://doi.org/10.1016/j.juro.2016.02.656AboutPDF ToolsAdd to favoritesDownload CitationsTrack CitationsPermissionsReprints ShareFacebookTwitterLinked InEmail INTRODUCTION AND OBJECTIVES Salvage Robotic-Assisted Laparoscopic Prostatectomy is a treatment option for biochemical recurrence in prostate cancer. We report the results of salvage robotic vs. open radical prostatectomy and the role of Choline PET in salvage prostatectomy. METHODS We conducted a retrospective analysis of 47 salvage robotic or open prostatectomies performed at two tertiary centres between 2007-2015. Patient records were examined to collate: primary therapy, oncological outcomes, survival outcomes, biochemical free survival. Records were also examined to review whether PET scans had been conducted (F18 Choline PET). In patients who had had PET scans, the following were examined for evidence of recurrence or metastases: PET scans in those on androgen deprivation therapy/ chemotherapy for biochemical recurrence, evidence of metastases in patients with biochemical recurrence but not on treatment, evidence of recurrence patients with a positive margin and lastly patients with normal PSA post operatively. We also examine the PSA level for which the PET scans are positive for localised disease, locally advanced/ pelvic disease or metastases. RESULTS Of the 47 procedures, 25 were conducted as open, 22 were robotic. 38 patients had prior hormones and radiotherapy, six patients had brachytherapy, two patients had brachytherapy in conjunction with radiotherapy, and one had HIFU. The biochemical relapse free rate within the robotic group was 66.6% compared to 40.0% in the open group. 16 cases had choline PET scans conducted. 3 cases went on to require androgen deprivation therapy - recurrence was demonstrated on PET scanning in all cases. Of the 16 cases, 4 patients had positive margins, 3 of which had positive findings PET scans (all went on to have radiotherapy). Seven cases had an undetectable PSA at the end of treatment, five of which of which had a positive PET scan prior to salvage therapy. Local recurrence within the prostate was demonstrated at a PSA level of <0.03, single lesion. Locally advanced pelvic nodal disease was demonstrated at PSAs of <0.03, single lesion. PSA levels of 3 determined pre-sacral nodal disease, with levels of 6 demonstrating vertebral metastases. CONCLUSIONS The role of Choline PET scanning has not been clearly outlined in salvage therapy. This study although small demonstrates the role PET scanning would have in salvage therapy. It also demonstrates a role for PET in assessing patients with differing values of PSA, where there is suspicion of recurrence. © 2016FiguresReferencesRelatedDetails Volume 195Issue 4SApril 2016Page: e753 Advertisement Copyright & Permissions© 2016MetricsAuthor Information Sanchia Goonewardene More articles by this author Gideon Bletcher More articles by this author Rick Catterwell More articles by this author Declan Cahill More articles by this author Raj Persad More articles by this author David Gillatt More articles by this author Ben Challacombe More articles by this author Prokar Dasgupta More articles by this author Rick Popert More articles by this author Expand All Advertisement Advertisement PDF downloadLoading ...

Efficacy of eradicative radiotherapy for limited nodal metastases detected with choline PET scan in prostate cancer patients.

In patients with recurrent prostate cancer, discriminating local or systemic recurrence is critical to decide second-line treatment. We investigated the capability of stereotactic body radiotherapy to treat limited nodal recurrences, detected using choline PET scan. Seventy-one patients with biochemical failure were studied after prostate cancer treatment: prostatectomy (28), radiotherapy (15) or both (28). Following computed tomography and choline PET imaging, stereotactic body radiotherapy was delivered on pathological lymphatic areas by 6 MV Linac, using dynamic micromultileaf collimation and intensity-modulated arc therapy optimization. Sixty days post-treatment, choline PET/CT imaging was carried out. Median follow-up was 29 months (range, 14.4-48). Choline PET detected recurrences in 39 of 71 patients. Median PSA velocity was 0.40 ng/ml/year in PET-negative patients and 2.88 ng/ml/year in PET-positive subjects (P < 0.05). Twenty-five patients with limited nodal recurrences, out of the 71 submitted to choline PET, received eradicative radiotherapy. Persistent regression was recorded in 13; early spread to bone was found in 2 cases; lymph node recurrences in 8, all in sites outside the irradiated areas; 2 patients were lost to follow-up. At the 3-year follow-up, overall survival, disease-free survival and local control rates were 92%, 17% and 90%, respectively. In patients with a complete regression, PSA fell from 5.65 to 1.40 ng/ml (median). PSA nadir value (median 1.06 ng/ml) was maintained for 5.6 months (median). Stereotactic body radiotherapy was effective in disease eradication of limited nodal recurrences from prostate cancer, saving patients from, or at least postponing, systemic treatments.

Is choline PET useful for identifying intraprostatic tumour lesions? A literature review.

More than 80% of patients with intermediate-risk or high-risk localized prostate cancer are cured with radiation doses of 74-78 Gy, but high doses increase the risk for late bowel and bladder toxicity among long-term survivors. Dose painting, defined as dose escalation to areas in the prostate containing the tumour, rather than to the whole gland, minimizes dose to normal tissues and hence toxicity. It requires accurate identification of the location and size of these lesions, for which functional MRI is the current gold standard. Many studies have assessed the use of choline PET in staging newly diagnosed patients. This review will discuss important imaging variables affecting the accuracy of choline PET scans, how choline PET contributes to tumour identification and is used in radiotherapy planning and how PET can improve the patient pathway involving prostate radiotherapy. In summary, the available literature shows that the accuracy of choline PET improves with higher tracer doses and delayed imaging (although the optimal uptake time is unclear), and tumour identification by MRI is improved by the addition of PET imaging. We propose future research with prolonged choline uptake time and multiphase imaging, which may further improve accuracy.

Analysis of Intraprostatic Therapeutic Effects in Prostate Cancer Patients Using [11C]-Choline pet/ct after External-Beam Radiation Therapy

The objective of the present study was to analyze, with relatively high sensitivity and specificity, uptake properties of [(11)C]-choline in prostate cancer patients by means of positron-emission tomography (pet)/computed tomography (ct) imaging using objectively defined pet parameters to test for statistically significant changes before, during, and after external-beam radiation therapy (ebrt) and to identify the time points at which the changes occur. The study enrolled 11 patients with intermediate-risk prostate cancer treated with ebrt, who were followed for up to 12 months after ebrt. The [(11)C]-choline pet scans were performed before treatment (baseline); at weeks 4 and 8 of ebrt; and at 1, 2, 3, 6, and 12 months after ebrt. Analysis of [(11)C]-choline uptake in prostate tissue before treatment resulted in a maximum standardized uptake value (suvmax) of 4.0 ± 0.4 (n = 11) at 40 minutes after injection. During week 8 of ebrt, the suvmax declined to 2.9 ± 0.1 (n = 10, p < 0.05). At 2 and 12 months after ebrt, suvmax values were 2.3 ± 0.3 (n = 10, p < 0.01) and 2.2 ± 0.2 (n = 11, p < 0.001) respectively, indicating that, after ebrt, maximum radiotracer uptake in the prostate was significantly reduced. Similar effects were observed when analyzing the tumour:muscle ratio (tmr). The tmr declined from 7.4 ± 0.6 (n = 11) before ebrt to 6.1 ± 0.4 (n = 11, nonsignificant) during week 8 of ebrt, to 5.6 ± 0.03 (n = 11, p < 0.05) at 2 months after ebrt, and to 4.4 ± 0.4 (n = 11, p < 0.001) at 12 months after ebrt. Our study demonstrated that intraprostatic [(11)C]-choline uptake in the 11 analyzed prostate cancer patients significantly declined during and after ebrt. The pet parameters SUVmax and tmr also declined significantly. These effects can be detected during radiation therapy and up to 1 year after therapy. The prognostic value of these early and statistically significant changes in intraprostatic [(11)C]-choline pet avidity during and after ebrt are not yet established. Future studies are indicated to correlate changes in [(11)C]-choline uptake parameters with long-term biochemical recurrence to further evaluate [(11)C]-choline pet changes as a possible, but currently unproven, biomarker of response.

Efficacy of Eradicative Radiotherapy for Limited Nodal Metastases Detected with Choline PET Scan in Prostate Cancer Patients

In patients with recurrent prostate cancer, discriminating local or systemic recurrence is critical to decide second-line treatment. We investigated the capability of stereotactic body radiotherapy to treat limited nodal recurrences, detected using choline PET scan. Seventy-one patients with biochemical failure were studied after prostate cancer treatment: prostatectomy (28), radiotherapy (15) or both (28). Following computed tomography and choline PET imaging, stereotactic body radiotherapy was delivered on pathological lymphatic areas by 6 MV Linac, using dynamic micromultileaf collimation and intensity-modulated arc therapy optimization. Sixty days post-treatment, choline PET/CT imaging was carried out. Median follow-up was 29 months (range, 14.4-48). Choline PET detected recurrences in 39 of 71 patients. Median PSA velocity was 0.40 ng/ml/year in PET-negative patients and 2.88 ng/ml/year in PET-positive subjects (P < 0.05). Twenty-five patients with limited nodal recurrences, out of the 71 submitted to choline PET, received eradicative radiotherapy. Persistent regression was recorded in 13; early spread to bone was found in 2 cases; lymph node recurrences in 8, all in sites outside the irradiated areas; 2 patients were lost to follow-up. At the 3-year follow-up, overall survival, disease-free survival and local control rates were 92%, 17% and 90%, respectively. In patients with a complete regression, PSA fell from 5.65 to 1.40 ng/ml (median). PSA nadir value (median 1.06 ng/ml) was maintained for 5.6 months (median). Stereotactic body radiotherapy was effective in disease eradication of limited nodal recurrences from prostate cancer, saving patients from, or at least postponing, systemic treatments.

Reproducibility of [11C]Choline-Positron Emission Tomography and Effect of Trastuzumab

This study sought to evaluate the reproducibility of [(11)C]choline-positron emission tomography and the effect of trastuzumab in breast cancer. Twenty-one patients with newly diagnosed and recurrent breast cancer stage II-IV had a baseline dynamic [(11)C]choline-PET scan, 10 patients had a second [(11)C]choline-PET scan to examine reproducibility, and 6 patients had a second scan within a month after trastuzumab. Analysis of [(11)C]choline uptake was measured as the semiquantitative standardized uptake value at 30 and 60 minutes (SUV(30) and SUV(60)), and quantitatively as the net irreversible retention of the radiotracer at steady-state (Ki) and plasma to tissue exchange at 60 minutes (IRF60min). Breast tumor lesions in all patients were visualized by [(11)C]choline PET. The difference in tumor versus normal tissue uptake was significant for SUV(30), SUV(60), Ki, and IRF60 minutes (Wilcoxon P < 0.0001). At 60 minutes postinjection, 15.1 +/- 2.16% of plasma radioactivity was due to unmetabolized [(11)C]choline radioactivity. [(11)C]Choline uptake was reproducible in breast tumor lesions (r(2) = 0.9 for SUV, 0.9 for Ki, and 0.8 for IRF60). Early responses to trastuzumab measured by [(11)C]choline-PET were significant in three lesions occurring in two patients who responded clinically. [(11)C]Choline-PET uptake variables can be reproducibly assessed. Initial studies show that trastuzumab decreases [(11)C]choline uptake.

11C]Choline-PET imaging of breast cancer

1110 Background: Molecular imaging techniques are increasingly being used in cancer diagnosis, staging, and assessment of response to treatment. This study sought to evaluate, for the first time, [11C]choline-PET in patients with breast cancer. The potential of [11C]choline-PET for differentiating tumours from normal tissue, correlation with molecular markers, determine its normal variability range, and finally the effect of trastuzumab on [11C]choline uptake in patients with breast cancer was investigated. Methods: 21 patients with newly diagnosed and recurrent breast cancer AJCC stage II-IV were enrolled in the study, all of whom had a baseline dynamic [11C]choline-PET scan with arterial sampling. 14 patients had 2 [11C]choline-PET scans to examine reproducibility, and 7 had a scan after trastuzumab. Analysis of [11C]choline uptake was measured using SUV, Ki (irreversible retention), and IRF@60min (retention using spectral analysis). Results: Breast tumour lesions were visualised by [11C]choline PET in all patients. The difference in tumour and non-tumour uptake were significant for SUV, Ki, and IRF@60 min (Wilcoxon p &lt; 0.0001 for all parameters). [11C]choline uptake was reproducible in breast tumour lesions (r2 = 0.945 for SUV, 0.894 for Ki, and 0.799 for IRF60). The metabolism analysis of arterial plasma samples in 19 patients showed that [11C]choline decreased rapidly post-injection such that at 60 mins the mean radioactivity in arterial plasma due to choline was 15.15 ± 2.16%.Early responses to trastuzumab were determined to be significant in 5 lesions which corresponded with 3 clinical responses. Conclusions: [11C]choline-PET is a promising imaging modality in breast cancer, and could play an important role for determining response to novel treatment strategies in vivo. No significant financial relationships to disclose.

Graft-versus-tumor effect following reduced-intensity allogeneic stem cell transplantation in prostate cancer

6551 Background: Allogeneic transplantation has been utilized as adoptive immunotherapy for patients with solid tumors resistant to conventional therapy. Methods: In 2001 we started a pilot study of allogeneic hematopoietic cell transplantation after a reduced-intensity regimen in patients with metastatic, androgen-independent prostate cancer, aged 18–70, ECOG PS 0–1. Planned sample size was 10 patients. Primary endpoint was feasibility of the procedure. The conditioning regimen included thiotepa, fludarabine, and cyclophosphamide. Patients received allogeneic peripheral blood cells from an HLA-identical sibling. A median of 6.9×10e6 CD34+ cells/kg were infused (range 4.8–11.8). Graft-versus-Host Disease (GvHD) prophylaxis consisted of cyclosporine A and short-course methotrexate. All the patients were evaluable for engraftment and chimerism. Results: Six patients have been enrolled. The median age was 61 years (range 51–66). The median time to reach an absolute neutrophil count of 1.0×10e9/l and a platelet count of 20×10e9/l was 11 and 12 days respectively (range 10–14 and 11–16). All patients achieved complete lymphoid- and myeloid-chimerism at day +90 by cytogenetics or by VNTR polymorphism analysis. Median day of cyclosporine A withdrawal was +85. Three patients developed acute GvHD grade ≥2, usually soon after cyclosporine withdrawal. At a median follow-up of 401 days (range 93–682), 2 patients are alive and 4 died, 2 for disease progression (+214 and +275), one for CMV disease (+93) and one for hemorrhagic cystitis (+527). This last patient achieved an almost complete response confirmed on choline-PET scan after cyclosporine withdrawal and limited chronic GvHD. In other 4 patients we observed a PSA reduction, concurrently with cyclosporine withdrawal or development of GvHD. Conclusions: The close association between GvHD and/or cyclosporine withdrawal and tumor responses strongly suggests that tumor regression was associated with an immune-mediated reaction related to allografting. Future strategies will aim at enhancing the anti-tumor effect and at decreasing GvHD and transplant-related mortality. No significant financial relationships to disclose.

Value of integrated PET/CT for lesion localisation in cancer patients: a comparative study

The aim of this study was to retrospectively compare the value of integrated PET/CT and separate PET plus morphological imaging studies for lesion localisation in cancer patients. Two different series of consecutive patients who had previously been treated for neoplastic disease were considered. One series consisted of 105 patients who had undergone [(18)F]fluorodeoxyglucose (FDG) PET/CT ( n=70) or [(11)C]choline PET/CT ( n=35) studies (PET/CT group). The other series comprised 105 patients who had undergone FDG PET scan ( n=70) or [(11)C]choline PET scan ( n=35) alone; in this series, PET findings were correlated with the results of morphological imaging (MI) studies, i.e. CT ( n=92) or MR imaging ( n=13) (PET+MI group). Regions of abnormal tracer uptake at PET scanning were classified as ambiguous or unambiguous depending on their precise anatomical localisation. A total of 207 and 196 lesions were found in the PET/CT and PET+MI groups, respectively. The difference in terms of number of lesions per patient detected with the two imaging protocols was not statistically significant ( P=0.718). When analysis of lesion localisation was performed, there were 7/207 (3.4%) and 30/196 (15.3%) ambiguous lesions in the PET/CT and PET+MI groups, respectively. The number of ambiguous lesions was significantly higher in the PET+MI group than in the PET/CT group (chi(2)=15.768, P<0.0001). Comparison of the effect of use of the different tracers on reporting of PET/CT versus PET+MI revealed that the improvement in the final report in [(11)C]choline PET/CT studies was similar to that observed in [(18)F]FDG studies. In cancer patients, PET/CT shows higher diagnostic accuracy for lesion localisation than PET plus morphological imaging studies performed independently. This result does not seem to be affected by the type of tracer used.