Lutetium [177Lu]-DOTA-TATE in gastroenteropancreatic-neuroendocrine tumours: rationale, design and baseline characteristics of the Italian prospective observational (REAL-LU) study.

PURPOSE: Gastroenteropancreatic -neuroendocrine tumours (GEP-NETs) are commonly treated with surgical resection or long-term therapies for tumour growth control. Lutetium [177Lu]-DOTA-TATE was approved for the treatment of GEP-NETs after the phase III NETTER 1trial demonstrated improved progression free survival, objective response rates and health-related quality of life (HRQoL) compared to high-dose somatostatin analogues. No real-world data exist on prescribing habits and clinically significant endpoints for [177Lu]Lu-DOTA-TATE treatment in Italy. REAL-LU is a multicentre, long-term observational study in patients with unresectable/metastatic GEP-NETs progressing on standard therapies in Italian clinical practice. A pre-specified interim analysis was performed at the end of the enrolment period, data from which are described herein. METHODS: Overall duration of REAL-LU will be approximately 48 months, with 12- and 36-month recruitment and follow-up periods, respectively. The primary objective is to evaluate [177Lu]Lu-DOTA-TATE effectiveness in terms of progression-free survival. Secondary objectives include safety, impact on HRQoL, and identification of prognostic factors. This pre-specified interim analysis describes patient profiles, at the end of enrollment, of those prescribed [177Lu]Lu-DOTA-TATE for GEP-NETs in Italy. RESULTS: Among 161 evaluable patients, mean age was 64.7 ± 10.3 years at study entry, 83.8% presented with no clinical signs of disease at physical examination, and most had minor disease symptoms. All patients had metastatic disease, most commonly in the liver (83.9%) with a median of two metastatic sites. In 90.7% of patients, the disease was stage IV, and 68.3% had ≥ 1 target lesion. [177Lu]Lu-DOTA-TATE was prescribed mainly as second-line therapy (61.6%) and following surgery (58.4%). HRQoL assessments revealed high levels of functioning and low levels of symptoms at baseline; 50.0% of patients were symptom-free at study entry. CONCLUSION: The characteristics of patients who received [177Lu]Lu-DOTA-TATE in Italy are similar to those of the GEP-NET population of NETTER 1 with trial but with a higher proportion of patients with a grade 2 (71%). With regard to the tumor grade profile, our study cohort appears to be closer to that of NETTER-2 study population which included patients with G2 or G3 advanced GEP-NETs (i.e. Ki-67 ≥ 10% and ≤ 55%). Further analysis of effectiveness and safety can be anticipated as REAL-LU data mature. STUDY REGISTRATION: ClinicalTrials.gov, NCT04727723; Study Registration Date: 25 January, 2021; https://clinicaltrials.gov/study/NCT04727723?cond=NCT04727723&rank=1.

The role of preoperative [11C]methionine PET in defining tumor-related epilepsy and predicting short-term postoperative seizure control in temporal lobe low-grade gliomas.

OBJECTIVE: Surgery is the mainstay of treatment for low-grade glioma (LGG)-related epilepsy. However, the goal of achieving both oncological radical resection and seizure freedom can be challenging. PET with [11C]methionine (MET) has been recently introduced in clinical practice for the management of patients with LGGs, not only to monitor the response to treatments, but also as a preoperative tool to define the metabolic tumor extent and to predict tumor grading, type, and prognosis. Still, its role in defining tumor-related epilepsy and postoperative seizure outcomes is limited. The aim of this preliminary study was to investigate the role of MET PET in defining preoperative seizure characteristics and short-term postoperative seizure control in a cohort of patients with newly diagnosed temporal lobe low-grade gliomas (tLGGs). METHODS: Patients with newly diagnosed and histologically proven temporal lobe grade 2/3 gliomas (2021 WHO CNS tumor classification) who underwent resection at the authors' institution between July 2011 and March 2021 were included in this retrospective study. MET PET images were acquired, fused with MRI scans, and qualitatively and semiquantitatively analyzed. Any eventual PET/MRI involvement of the temporomesial area, seizure characteristics, and 1-year seizure outcomes were reported. RESULTS: A total of 52 patients with tLGGs met the inclusion criteria. MET PET was positive in 41 (79%) patients, with a median metabolic tumor volume of 14.56 cm3 (interquartile range [IQR] 6.5-28.2 cm3). The median maximum and mean tumor-to-background ratio (TBRmax, TBRmean) were 2.24 (IQR 1.58-2.86) and 1.53 (IQR 1.37-1.70), respectively. The metabolic tumor volume was found to be related to the presence of seizures at disease onset, but only in noncodeleted tumors (p = 0.014). Regarding patients with uncontrolled seizures at surgery, only the temporomesial area PET involvement showed a statistical correlation both in the univariate (p = 0.058) and in the multivariate analysis (p = 0.030). At 1-year follow-up, seizure control was correlated with MET PET-derived semiquantitative data. Particularly, higher TBRmax (p = 0.0192) and TBRmean (p = 0.0128) values were statistically related to uncontrolled seizures 1 year after surgery. CONCLUSIONS: This preliminary study suggests that MET PET may be used as a preoperative tool to define seizure characteristics and outcomes in patients with tLGGs. These findings need to be further validated in larger series with longer epileptological follow-ups.

Radioisotope-Guided Excision of Mediastinal Lymph Nodes in Patients with Non-Small Cell Lung Carcinoma: Feasibility and Clinical Impact.

BACKGROUND: Intraoperative localisation of nodal disease in non-small cell lung cancer (NSCLC) can be challenging. Lymph node localisation via radiopharmaceuticals is used in many conditions; we tested the feasibility of this approach in NSCLC. METHODS: NSCLC patients were prospectively recruited. Intraoperative peri-tumoral injections of [99mTc]Tc-albumin nanocolloids were performed, followed by removing the tumour and locoregional lymph nodes. These were examined ex vivo with a gamma probe and labelled sentinel lymph nodes (SLNs) if they showed any activity or non-sentinel lymph nodes (nSLNs) if they did not. Thereafter, the surgical field was scanned with the probe; any further radioactive lymph node was removed and labelled as "extra" SLNs (eSLNs). All specimens were sent to histology, and metastatic status was recorded. RESULTS: 48 patients were enrolled, and 290 nodal stations were identified: 179 SLNs, 87 nSLNs, and 24 eSLNs. A total of 44 nodal metastases were identified in 22 patients, with 36 of them (82%) located within SLNs. Patients with nSLNs metastases had at least a co-existing positive SLN. No metastases were found in eSLNs. CONCLUSIONS: The technique shows high sensitivity for intraoperative nodal metastases identification. This information could allow selective lymphadenectomies in low-risk patients or more aggressive approaches in high-risk patients.

Internal Guidelines for Reducing Lymph Node Contour Variability in Total Marrow and Lymph Node Irradiation.

BACKGROUND: The total marrow and lymph node irradiation (TMLI) target includes the bones, spleen, and lymph node chains, with the latter being the most challenging structures to contour. We evaluated the impact of introducing internal contour guidelines to reduce the inter- and intraobserver lymph node delineation variability in TMLI treatments. METHODS: A total of 10 patients were randomly selected from our database of 104 TMLI patients so as to evaluate the guidelines' efficacy. The lymph node clinical target volume (CTV_LN) was recontoured according to the guidelines (CTV_LN_GL_RO1) and compared to the historical guidelines (CTV_LN_Old). Both topological (i.e., Dice similarity coefficient (DSC)) and dosimetric (i.e., V95 (the volume receiving 95% of the prescription dose) metrics were calculated for all paired contours. RESULTS: The mean DSCs were 0.82 ± 0.09, 0.97 ± 0.01, and 0.98 ± 0.02, respectively, for CTV_LN_Old vs. CTV_LN_GL_RO1, and between the inter- and intraobserver contours following the guidelines. Correspondingly, the mean CTV_LN-V95 dose differences were 4.8 ± 4.7%, 0.03 ± 0.5%, and 0.1 ± 0.1%. CONCLUSIONS: The guidelines reduced the CTV_LN contour variability. The high target coverage agreement revealed that historical CTV-to-planning-target-volume margins were safe, even if a relatively low DSC was observed.

Contrast Enhanced EUS for Predicting Solid Pancreatic Neuroendocrine Tumor Grade and Aggressiveness.

Pancreatic neuroendocrine tumor (PNET) behavior assessment is a daily challenge for physicians. Modern PNET management varies from a watch-and-wait strategy to surgery depending on tumor aggressiveness. Therefore, the aggressiveness definition plays a pivotal role in the PNET work-up. The aggressiveness of PNETs is mainly based on the dimensions and histological grading, with sometimes a lack of specificity and sensibility. In the last twenty years, EUS has become a cornerstone in the diagnostic phase of PNET management for its high diagnostic yield and the possibility of obtaining a histological specimen. The number of EUS applications in the PNET work-up has been rapidly increasing with new and powerful possibilities. The application of contrast has led to an important step in PNET detection; in recent years, it has been gaining interesting applications in aggressiveness assessment. In this review, we underline the latest experiences and opportunities in the behavior assessment of PNETs using contact-enhanced EUS and contested enhanced harmonic EUS with a particular focus on the future application and possibility that these techniques could provide.

Multidisciplinary Tumor Board in the Management of Patients with Colorectal Liver Metastases: A Single-Center Review of 847 Patients.

There is still debate over how reviewing oncological histories and addressing appropriate therapies in multidisciplinary team (MDT) discussions may affect patients' overall survival (OS). The aim of this study was to describe MDT outcomes for a single cancer center's patients affected by colorectal liver metastases (CRLMs). From 2010 to 2020, a total of 847 patients with CRLMs were discussed at our weekly MDT meeting. Patients' characteristics and MDT decisions were analyzed in two groups: patients receiving systemic therapy (ST) versus patients receiving locoregional treatment (LRT). Propensity-score matching (PSM) was run to reduce the risk of selection bias. The median time from MDT indication to treatment was 27 (IQR 13−51) days. The median OS was 30 (95%CI = 27−34) months. After PSM, OS for patients undergoing LRT was 51 (95%CI = 36−64) months compared with 15 (95%CI = 13−20) months for ST patients (p < 0.0001). In this large retrospective study, the MDT discussions were useful in providing the patients with all available locoregional options.

Dose-dense ABVD as first-line therapy in early-stage unfavorable Hodgkin lymphoma: results of a prospective, multicenter double-step phase II study by Fondazione Italiana Linfomi.

We investigated the feasibility and activity of an intensified dose-dense ABVD (dd-ABVD) regimen in patients with early-stage unfavorable Hodgkin lymphoma (HL). This prospective, multicenter, phase II study enrolled 96 patients with newly diagnosed, unfavorable stage I or II classical HL. The patients received four cycles of dd-ABVD followed by radiotherapy. Interim PET (PET-2) was mandatory after two courses. Primary endpoints were the evaluation of dd-ABVD feasibility and activity (incidence of PET-2 negativity). The feasibility endpoint was achieved with 48/52 (92.3%) patients receiving > 85% of the programmed dose. The mean dose intensity in the overall patient population (n = 96) was 93.7%, and the median duration of dd-ABVD was 85 days (range, 14-115) versus an expected duration of 84 days. PET-2 was available for 92/96 (95.8%) patients, of whom 79 were PET-2 negative (85.9%). In total, 90 (93.8%) patients showed complete response at the end of treatment. With a follow-up of 80.9 months (3.3-103.2), the median progression-free survival (PFS) and overall survival (OS) were not reached. At 84 months, PFS and OS rates were 88.4% and 95.7%, respectively. No evidence for a difference in PFS or OS was observed for PET-2-negative and PET-2-positive patients. Infections were documented in 8.3% and febrile neutropenia in 6.2% of cases. Four patients died: one had alveolitis at cycle 3, one death was unrelated to treatment, and two died from a secondary cancer. dd-ABVD is feasible and demonstrates activity in early-stage unfavorable HL. The predictive role of PET-2 positivity in early-stage unfavorable HL remains controversial. The study was registered in the EudraCT (reference number, 2011-003,191-36) and the ClinicalTrials.gov (reference number, NCT02247869) databases.

Morphometric vertebral fractures in patients with castration-resistant prostate cancer undergoing treatment with radium-223: a longitudinal study in the real-life clinical practice.

PURPOSE: Radium-223 was associated with high incidence of non-vertebral fractures in patients with castration-resistant prostate cancer (CRPC). However, it is still unclear whether radium-223 may induce skeletal fragility regardless of other therapies for CRPC. We aimed at evaluating the prevalence, incidence, and determinants of vertebral fractures (VFs), i.e., the most frequent complication of skeletal fragility, in CRCP patients undergoing radium-223 therapy in the real-life clinical practice. METHODS: We retrospectively reviewed 49 CRPC patients with symptomatic bone metastases treated with radium-223. Patients received median number of four radium-223 doses (range: 2-6) and were followed-up for a median period of 11 months (range: 6-44). VFs were assessed by a quantitative morphometry using lateral images of spine 11C-Choline PET/CT, excluding from the analysis the vertebral bodies affected by bone metastases. RESULTS: Before radium-223 administration, 24 patients (49%) had VFs significantly associated with duration of androgen deprivation therapy (ADT; odds ratio 1.29) and previous abiraterone therapy (odds ratio 3.80). During radium-223 therapy, incident VFs occurred in 25% of patients, in relationship with prevalent VFs (hazard ratio 6.89) and change in serum total alkaline phosphatase values (hazard ratio 0.97), whereas the correlations with ADT and abiraterone therapy were lost. Noteworthy, the risk of VFs did not correlate with the therapeutic end points of radium-223. CONCLUSIONS: This study provides a first evidence that in real-life clinical practice, radium-223 therapy may induce skeletal fragility with high risk of VFs, likely by inhibition of bone formation and independently of ADT and abiraterone therapy.

Prevention of Orbitopathy by Oral or Intravenous Steroid Prophylaxis in Short Duration Graves' Disease Patients Undergoing Radioiodine Ablation: A Prospective Randomized Control Trial Study.

Background: Radioiodine (RAI) is a known risk factor for activation or de novo occurrence of Graves' orbitopathy (GO). Several studies demonstrated that GO can be prevented by glucocorticoids (GCs) in patients with pre-existing GO. We have previously shown that Graves' disease duration (GDd) <5 years is a risk factor for RAI-induced GO. We studied the effect of prophylaxis with either oral GCs (OGCs) or intravenous GCs (IVGCs) on GO activation in patients with GDd. Methods: In total, 99 hyperthyroid patients without GO or with pre-existing inactive GO with GDd <5 years were randomized to receive IVGCs (N = 49) or OGCs (N = 50) before RAI; 22 patients with GDd >5 did not receive steroids and were studied as controls. All patients underwent ophthalmological assessment before and 45, 90, 180 days and for a 5-year follow-up after RAI. Serum thyrotropin (TSH) receptor antibodies (TRAbs), thyroid hormones, and thyroid volume (TV) were also measured in response to RAI therapy and steroid prophylaxis. Results: No patient on prophylaxis developed GO after RAI. One woman of the control group, without steroid prophylaxis, and who had a marked elevation of her TSH, showed transient reactivation of GO, which spontaneously improved after restoring euthyroidism. On follow-up at 12 and 20 months after RAI, two patients developed overt optic neuropathy. A smaller TV was associated with a higher prevalence of RAI-induced hypothyroidism. Serum TRAbs increased significantly after RAI (p < 0.0001) but less in patients receiving steroids than in those without prophylaxis at 45 days (p < 0.01). Conclusions: The risk of RAI-induced GO can be prevented in all patients with GDd <5 years by steroids. Such treatment may not be necessary in patients with GDd >5 years. The blunting of TRAb elevation after RAI may be related to the prophylactic effect of steroids.

Real-Time US-18FDG-PET/CT Image Fusion for Guidance of Thermal Ablation of 18FDG-PET-Positive Liver Metastases: The Added Value of Contrast Enhancement.

PURPOSE: To assess the feasibility of US-18FDG-PET/CT fusion-guided microwave ablation of liver metastases either poorly visible or totally undetectable with US, CEUS and CT, but visualized by PET imaging. MATERIALS AND METHODS: Twenty-three patients with 58 liver metastases underwent microwave ablation guided by image fusion system that combines US with 18FDG-PET/CT images. In 28/58 tumors, 18FDG-PET/CT with contrast medium (PET/CECT) was used. The registration technical feasibility, registration time, rates of correct targeting, technical success at 24 h, final result at 1 year and complications were analyzed and compared between the PET/CT and PET/CECT groups. RESULTS: Registration was successfully performed in all cases with a mean time of 7.8 + 1.7 min (mean + standard deviation), (4.6 + 1.5 min for PET/CECT group versus 10.9 + 1.8 min for PET/CT group, P < 0.01). In total, 46/58 (79.3%) tumors were correctly targeted, while 3/28 (10.7%) and 9/30 (30%) were incorrectly targeted in PET/CT and PET/CECT group, respectively (P < 0.05). Complete ablation was obtained at 24 h in 70.0% of cases (n = 40 tumors), 23/28 (82.1%) in the PET/CECT group and 17/30 (56.7%) in the PET/CT group (P < 0.037). Fourteen tumors underwent local retreatment (11 ablations, 2 with resection and 1 with stereotactic body radiation therapy), while 4 tumors could not be retreated because of distant disease progression and underwent systemic therapy. Finally, 54/58 (93.1%) tumors were completely treated at 1 year. One major complication occurred, a gastrointestinal hemorrhage which required surgical repair. CONCLUSIONS: Percutaneous ablation of 18FDG-PET-positive liver metastases using fusion imaging of real-time US and pre-acquired 18FDG-PET/CT images is feasible, safe and effective. Contrast-enhanced PET/CT improves overall ablation accuracy and shortens procedural duration time.

Correction to: Radioiodine ablation with 1,850 MBq in association with rhTSH in patients with differentiated thyroid cancer.

Unfortunately, the fourth author's middle name was missed out in the original publication of this article. The complete correct name should read as follows.

Targeted 11C-choline PET-CT/TRUS software fusion-guided prostate biopsy in men with persistently elevated PSA and negative mpMRI after previous negative biopsy.

BACKGROUND: We evaluated the feasibility and accuracy of 11C-choline PET-CT/TRUS fusion-guided prostate biopsy in men with persistently elevated PSA and negative mpMRI or contraindication to MRI, after previous negative biopsy. Clinical data were part of a prospective on-going observational clinical study: "Diagnostic accuracy of target mpMRI/US fusion biopsy in patients with suspected prostate cancer after initial negative biopsy". Patients with a negative biopsy and negative mpMRI (PI-RADS v.2 < 3) or absolute contraindications to MRI and persistently elevated PSA, were included. All patients underwent 11C-choline PET with dedicated acquisition of the pelvis and PET-CT/TRUS-guided prostate biopsy by Bio-Jet™ fusion system (D&K Technologies, Germany). The primary endpoint was to assess the accuracy of 11C-choline PET-CT to determine the presence and the topographical distribution of PCa. RESULTS: Overall, 15 patients (median age 71 yrs. ± 8.89; tPSA 13.5 ng/ml ± 4.3) were analysed. Fourteen had a positive PET scan, which revealed 30 lesions. PCa was detected in 7/15 patients (46.7%) and four patients presented a clinically significant PCa: GS > 6. Over 58 cores, 25 (43.1%) were positive. No statistically significant difference in terms of mean and median values for SUVmax and SUVratio between benign and malignant lesions was found. PCa lesions with GS 3 + 3 (n = 3) showed a median SUVmax and SUVratio of 4.01 and 1.46, compared to 5.45 and 1.57, respectively for lesions with GS >6 (n = 4). CONCLUSION: Software PET-CT/TRUS fusion-guided target biopsy could be a diagnostic alternative in patients with a suspected primary PCa and negative mpMRI, but its specificity appeared low.

Positron Emission Tomography-Computed Tomography for Patients with Recurrent Colorectal Liver Metastases: Impact on Restaging and Treatment Planning.

BACKGROUND: The impact of fluorodeoxyglucose positron emission tomography-computed tomography (PET-CT) for patients with colorectal liver metastases (CLM) still is debated. Its relevance could be enhanced in the case of recurrent disease. The current study aimed to elucidate the role of PET-CT in restaging and treatment planning for recurrent CLM. METHODS: A series of 352 consecutive patients undergoing their first liver resection for CLM between 2005 and 2014 was reviewed. Of these patients, 224 (63.6 %) had a recurrence. The 107 patients who had received PET-CT at diagnosis of recurrence before chemotherapy were analyzed. CT was available in all cases, and magnetic resonance imaging (MRI) was available in 64 cases. RESULTS: Extrahepatic lesions were found in 59 patients. Liver and lung recurrences were detected with excellent sensitivity by CT/MRI and PET-CT (liver: 100 vs. 96.7 %; lung: 95.8 vs. 95.8 %). In detecting other recurrence sites, PET-CT had higher sensitivity than CT/MRI (91.5 vs. 54.2 %, p < 0.01; lymph nodes: 93.5 vs. 64.5 %, p = 0.011; peritoneum: 80 vs. 20 %, p = 0.023; bones: 87.5 vs. 37.5 %, nonsignificant difference). For 28.8 % (17/59) of the patients, the diagnosis of extrahepatic disease was obtained thanks to PET-CT (39.5 % considering nonpulmonary lesions). PET-CT modified treatment strategy in 16 (14.9 %) patients, excluding from surgery 15 (20.3 %) of 74 patients resectable at CT/MRI. This latter subgroup had a lower survival rate than the patients resectable after PET-CT (2-year survival, 22.7 vs. 77.8 %; p = 0.004), similar to the patients unresectable at CT/MRI (57.6 %). CONCLUSIONS: In the authors' experience, PET-CT has offered a relevant contribution to restaging of recurrent CLM. It disclosed one fourth of extrahepatic lesions and prevented worthless surgery for about 20 % of patients.

B-IGEV (bortezomib plus IGEV) versus IGEV before high-dose chemotherapy followed by autologous stem cell transplantation in relapsed or refractory Hodgkin lymphoma: a randomized, phase II trial of the Fondazione Italiana Linfomi (FIL).

This randomized, multicenter study evaluates the addition of bortezomib (13 mg/m(2)) to IGEV (B-IGEV) in patients with relapsed/refractory Hodgkin Lymphoma (HL). Patients received either four courses of IGEV alone (n = 40) or B-IGEV (n = 40). The primary endpoint was the complete response (CR) proportion, evaluated by FDG-PET, after induction chemotherapy. CR proportion was 39% with B-IGEV and 53% with IGEV. PFS and OS were similar between the two groups (two-year PFS: 58% vs 56%; two-year OS: 93% vs 81%). The PET-negative status after treatment was the only variable favorably influencing both PFS (two-year PFS: 77% vs 40%; p = 0.002) and OS (two-year OS: 100% vs 76%; p < 0.001). Toxicity was overall similar with the two regimens. The addition of bortezomib to IGEV does not improve response in relapsed/refractory HL patients. However, its favorable therapeutic and safety profile, and the prognostic role of pre-transplant PET negativity in patients receiving IGEV-based regimens are confirmed.

Standardization and quantification in PET/CT imaging: tracers beyond FDG.

Standardization of FDG PET-CT is becoming a reality, at least in centers that perform clinical trials. Non-FDG radiopharmaceuticals used with PET/CT are far from standard in clinical trials and in clinical use. This article only gives an example of different protocols and indications related to the availability of different radiopharmaceuticals. This scenario will be probably the reality in the near future in many centers throughout the world. Starting from the FDG experience, it will be easy to implement standards for acquisition and interpretation of PET/CT studies with other radiopharmaceuticals.

Radioiodine ablation with 1,850 MBq in association with rhTSH in patients with differentiated thyroid cancer.

PURPOSE: The aim of this study was to evaluate the efficacy of post-operative radioiodine ablation with 1,850 MBq after recombinant human thyrotropin (rhTSH) administration in patients with differentiated thyroid carcinoma (DTC). We also aimed to assess the prognostic role of several patient features on the outcome of ablation. METHODS: We retrospectively analyzed data from a total of 125 patients with DTC who underwent post-operative radioiodine ablation with 1,850 MBq of ¹³¹I after preparation with rhTSH. One injection of 0.9 mg rhTSH was administered on each of two consecutive days; ¹³¹I therapy was delivered 24 h after the last injection, followed by a post-therapy whole-body scan. Successful ablation was assessed 6-12 months later and defined as an rhTSH-stimulated serum thyroglobulin (Tg) level ≤1.0 ng/ml and a normal neck ultrasound. RESULTS: Patients were stratified according to the American Thyroid Association (ATA) Management Guidelines for Differentiated Thyroid Cancer. Successful ablation was achieved in 82.4 % of patients, with an ablation rate of 95.1 % in low-risk patients and 76.2 % in intermediate-risk patients. Analyzing the correlation between ablation outcome and patient characteristics, we found a statistically significant association between failure to ablate and class of risk based on ATA guidelines (p = 0.025) and a stimulated Tg value at ablation of above 5 ng/ml (p < 0.001). CONCLUSION: The use of 1,850 MBq post-operative radioiodine thyroid remnant ablation in association with rhTSH is effective for low- and intermediate-risk patients. Moreover, in our study, we found a statistical correlation between failure to ablate and class of risk based on ATA guidelines for DTC and a stimulated Tg value at ablation.

[11C]choline PET/CT impacts treatment decision making in patients with prostate cancer referred for radiotherapy.

BACKGROUND: The purpose of our study was to analyze the role of [(11)C]choline-positron emission tomography/computed tomography (cho-PET/CT) in the management of patients with prostate cancer referred for radiotherapy. PATIENTS AND METHODS: Inclusion criteria for this retrospective study were (1) presence of prostate cancer, (2) referral for first radiotherapy course (for primary or recurrent tumor) between February 2007 and July 2010, and (3) performance of cho-PET/CT. All cho-PET/CT scans were classified according to whether they were positive in the prostate/prostate bed (T), pelvic lymph nodes (N), and distant metastases (M) or negative. Therapeutic strategy based on the cho-PET/CT evaluation was compared with the strategy that would have been proposed had cho-PET/CT imaging not been available, following international and national prostate cancer guidelines. RESULTS: Eighty-two cho-PET/CT scans performed in 74 patients were analyzed. Cho-PET/CT was positive in 49 studies (60%): T only in 22 (45% of all positive studies); N only in 4 (8%); T in combination with N in 3 (6%); and M in combination with T or N, or both, in 16 (33%). Treatment after positive cho-PET/CT examination included radiotherapy ± androgen deprivation (29 patients), surgery ± radiotherapy (6 patients), androgen deprivation only (8 patients), and other treatment (6 patients). In 22 cases, cho-PET/CT (27%) altered the treatment approach compared with the treatment that would have been adopted in the absence of cho-PET/CT analysis. CONCLUSION: Cho-PET/CT is valuable in defining the extent of disease and supporting therapeutic decisions in the management of prostate cancer. The therapeutic strategy turned out to be influenced by cho-PET/CT imaging in about one third of the patients included in this study.

Impact of 11C-methionine positron emission tomography/computed tomography on radiation therapy planning and prognosis in patients with primary brain tumors.

AIMS AND BACKGROUND: There is limited evidence regarding the impact of 11C-methionine positron emission tomography/computed tomography (MET-PET/CT) on radiation therapy planning of primary brain tumors. Our aim was to assess the effect of this imaging modality on treatment volumes and clinical outcome of patients eligible for radiation therapy in this oncologic setting. METHODS AND STUDY DESIGN: Between November 2009 and May 2012, 31 consecutive patients (male:female, 20:11; mean age, 53.0 years) with pathologically proven primary/relapsed glioma were treated with radiation therapy at the Humanitas Research Hospital. All patients were submitted to the same multi-imaging protocol including MET-PET/CT for biological target volume (PET) and contrast-enhanced magnetic resonance imaging/CT for gross tumor volume, in order to define the clinical target volume. Different volumes were compared and analyzed with respect to treatment planning modification after MET-PET/CT and impact on disease outcome. In 19/31 cases, patients were re-evaluated after completing radiotherapy, and in these cases, progression-free survival and overall survival were determined. The study was submitted to and data collection was approved by the local ethics committee. RESULTS: All patients completed the treatment. In 29 of 31 patients, a biological target volume was defined (mean volume, 18.3 cc), which in 20 cases (65%) resulted in a modification of the clinical target volume (mean, 65.9 cc; range, 8.5-165.6). In the other two cases, PET was negative and did not influence treatment planning. The mean percentage of added volume was 9.2%, ranging between -29% and 38%. With a mean follow-up of 5.4 months, treatment modification according to MET-PET/CT was the only predictor demonstrating a significant correlation with both progression-free survival ( P = 0.018) and overall survival (P = 0.003). None of the other factors evaluated in the analyses, including age, tumor histology, previous treatment, and tumor uptake, was correlated with the outcome. CONCLUSIONS: Despite the limited study population, our data indicate that MET-PET/CT can have a significant impact on radiation therapy planning in patients with primary brain tumors. Moreover, treatment modification according to PET appears to be a predictor of clinical outcome in this group of patients.