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The role of internal dosimetry is usually proposed for investigational purposes in patients treated by RLT, even if its application is not yet the standard method in clinical practice. This limited use is partially justified by several concomitant factors that make calculations a complex process. Therefore, simplified dosimetry protocols are required. Methods: In our study, dosimetric evaluations were performed in thirty patients with NENs who underwent RLT with [177Lu]Lu-DOTATATE. The reference method (M0) calculated the cumulative absorbed dose performing dosimetry after each of the four cycles. Obtained data were employed to assess the feasibility of simplified protocols: defining the dosimetry only after the first cycle (M1) and after the first and last one (M2). Results: The mean differences of the cumulative absorbed doses between M1 and M0 were – 10% for kidney, – 5% for spleen, + 34% for liver, + 13% for red marrow, and + 37% for tumor lesions. Conversely, differences lower than ± 10% were measured between M2 and M0. Conclusion: Cumulative absorbed doses obtained with the M2 protocol resembled the doses calculated by M0, while the M1 protocol overestimated the absorbed doses in all organs at risk, except for the spleen. [ABSTRACT FROM AUTHOR]

The aim of this work is to compare [68Ga]Ga-PSMA-11 and [18F]PSMA-1007 PET/CT as imaging agents in patients with prostate cancer (PCa). Comparisons were made by evaluating times and costs of the radiolabeling process, imaging features including pharmacokinetics, and impact on patient management. The analysis of advantages and drawbacks of both radioligands might help to make a better choice based on firm data. For [68Ga]Ga-PSMA-11, the radiochemical yield (RCY) using a low starting activity (L, average activity of 596.55 ± 37.97 MBq) was of 80.98 ± 0.05%, while using a high one (H, average activity of 1436.27 ± 68.68 MBq), the RCY was 71.48 ± 0.04%. Thus, increased starting activities of [68Ga]-chloride negatively influenced the RCY. A similar scenario occurred for [18F]PSMA-1007. The rate of detection of PCa lesions by Positron Emission Tomography/Computed Tomography (PET/CT) was similar for both radioligands, while their distribution in normal organs significantly differed. Furthermore, similar patterns of biodistribution were found among [18F]PSMA-1007, [68Ga]Ga-PSMA-11, and [177Lu]Lu-PSMA-617, the most used agent for RLT. Moreover, the analysis of economical aspects for each single batch of production corrected for the number of allowed PET/CT examinations suggested major advantages of [18F]PSMA-1007 compared with [68Ga]Ga-PSMA-11. Data from this study should support the proper choice in the selection of the PSMA PET radioligand to use on the basis of the cases to study. [ABSTRACT FROM AUTHOR]

Purpose: The extra-domain A1 of tenascin-C (TC-A1) is highly expressed in the extracellular matrix of tumours and on newly formed blood vessels and is thus a valuable target for radionuclide therapy. Tenarad is a fully human miniantibody or small immunoprotein (SIP, molecular weight 80 kDa) labelled with I that is derived from a TC-A1-binding antibody. Previous phase I/II studies with a similar compound (I-L19SIP) used for radioimmunotherapy (RIT) have shown preliminary efficacy in a variety of cancer types. In this ongoing phase I/II trial, Tenarad was administered to patients with recurrent Hodgkin's lymphoma (HL) refractory to conventional treatments. Methods: Eight patients (four men, four women; age range 19 - 41) were enrolled between April 2010 and March 2011. All patients had received a median of three previous lines of chemotherapy (range three to six) and seven had also undergone autologous stem cell transplantation (ASCT) or bone marrow transplantation. In addition, seven patients received external beam radiation. All patients had nodal disease, constitutional B symptoms and some showed extranodal disease in skeletal bone (four patients), lung (three), liver (two) and spleen (one). Baseline assessments included whole-body FDG PET with contrast-enhanced CT and diagnostic Tenarad planar and SPECT studies. Patients were considered eligible to receive a therapeutic dose of Tenarad (2.05 GBq/m) if tumour uptake was more than four times higher than that of muscle. Results: All patients were eligible and received the therapeutic dose of Tenarad. Only one patient developed grade 4 thrombocytopenia and leucocytopenia, requiring hospitalization and therapeutic intervention. All other patients had haematological toxicity of grade 3 or lower, which resolved spontaneously. At the first response assessment (4 - 6 weeks after therapy), one patient showed a complete response, one showed a partial response (PR) and five had disease stabilization (SD). Five patients were given up to three repeated Tenarad treatments. One patient showed SD which then improved to a PR, three showed clinical benefit while maintaining SD and one patient showed disease progression. Conclusion: Tenarad RIT is effective in chemorefractory HL and resulted in objective responses or clinical benefit in the majority of patients. Toxicity was acceptable despite the high load of prior treatments, previous ASCT and multiple Tenarad administrations. Further studies are planned to define the most effective schedule for this type of RIT in HL patients. [ABSTRACT FROM AUTHOR]

Abstract. Although mammography remains the technique of choice for the early detection of breast cancer, several imaging techniques, including scintimammography and magnetic resonance imaging (MRI), have recently been proposed as adjuncts for this purpose and included in many diagnostic protocols. This study was undertaken to assess the clinical accuracy of scintimammography with technetium-99m methoxyisobutylisonitrile (MIBI) and contrast-enhanced MRI in the detection of primary breast carcinoma in patients with equivocal mammographic findings. Forty-nine patients with a suspicious breast mass detected either by physical examination or by mammography and ultrasound (US) were studied. All patients underwent scintimammography and dynamic contrast-enhanced MRI 1 week apart. The results of the two techniques were compared and correlated to the final diagnoses. Two independent readers reported the scans using a four-point confidence scale. The areas under the receiver operator characteristic (ROC) curves were obtained. Scintimammography showed an accuracy for tumour detection of 84%, with a sensitivity of 80% and a specificity of 88%. MRI showed an accuracy of 86%, with a sensitivity and specificity of 96% and 75%, respectively. Comparison of the two areas under the ROC curves showed no significant differences between MRI, 0.91 +/- 0.05 (mean +/- SD), and scintimammography, 0.88 +/- 0.05 (P = 0.9). It is concluded that dynamic MRI and scintimammography possess comparable accuracy in the diagnosis of primary breast carcinoma in patients with equivocal mammographic or US findings. [ABSTRACT FROM AUTHOR]

Context: Lenvatinib is approved for the treatment of radioiodine-refractory differentiated thyroid cancer (RR-DTC). The definition of predictive factors of survival is incomplete., Objective: To identify pre- and posttreatment survival predictors in a real-life cohort of RR-DTC treated with lenvatinib., Design: Multicenter, retrospective, cohort study., Setting: 3 Italian thyroid cancer referral centers., Participants: 55 RR-DTC treated with lenvatinib., Main Outcome Measures: Progression-free survival (PFS) and overall survival (OS)., Results: Lenvatinib was the first-line kinase-inhibitor in 96.4% of subjects. Median follow-up was 48 months. Median PFS and OS were 26 [95% confidence interval (CI) 19.06-32.93] and 70 months (95% CI 36-111.99), respectively. Pretreatment setting: Eastern Cooperative Oncology Group (ECOG) performance status was independently related to PFS [P < .001; hazard ratio (HR) 18.82; 95% CI 3.65-97.08: score 0-1 as reference] and OS (P = .001; HR 6.20; 95% CI 2.11-18.20; score 0-1 as reference); radioactive iodine (RAI) avidity was independently related to PFS (P = .047; HR 3.74; 95% CI 1.01-13.76; avid disease as reference). Patients with good ECOG status (0-1) and RAI-avid disease obtained objective response in 100% of cases and achieved a median PFS of 45 months without any death upon a median follow-up of 81 months. Posttreatment setting: the best radiological response independently predicted PFS (P = .001; HR 4.6; 95% CI 1.89-11.18; partial/complete response as reference) and OS (P = .013; HR 2.94; 95% CI 1.25-6.89; partial/complete response as reference)., Conclusion: RR-DTC with good performance status and RAI-avid disease obtains the highest clinical benefit from lenvatinib. After treatment initiation, objective response was the only independent survival predictor., (© The Author(s) 2024. Published by Oxford University Press on behalf of the Endocrine Society. All rights reserved. For commercial re-use, please contact reprints@oup.com for reprints and translation rights for reprints. All other permissions can be obtained through our RightsLink service via the Permissions link on the article page on our site—for further information please contact journals.permissions@oup.com.)

There is an unmet need for predictive biomarkers of the clinical benefit of antiangiogenic drugs. The aim of the present study was to prospectively evaluate the value of 18 F-FDG PET/CT performed during and after preoperative chemoradiotherapy with bevacizumab for the prediction of complete pathologic tumor regression and survival in patients with MRI-defined high-risk locally advanced rectal cancer. Methods: Sixty-one patients treated in a nonrandomized phase II study (BRANCH) with concomitant or sequential (4 d before chemoradiotherapy) administration of bevacizumab with preoperative chemoradiotherapy were included. 18 F-FDG PET/CT was performed at baseline, 11 d after the beginning of chemoradiotherapy (early), and before surgery (late). Metabolic changes were compared with pathologic complete tumor regression (TRG1) versus incomplete tumor regression (TRG2-TRG5), progression-free survival, cancer-specific survival, and overall survival. Receiver-operating-characteristic curves were calculated for those 18 F-FDG PET/CT parameters that significantly correlated with TRG1. Results: Early total-lesion glycolysis and its percentage change compared with baseline (ΔTLG-early) could discriminate TRG1 from TRG2-TRG5. Only receiver-operating-characteristic analysis of ΔTLG-early showed an area under the curve greater than 0.7 (0.76), with an optimal cutoff at 59.5% (80% sensitivity, 71.4% specificity), for identifying TRG1. Late metabolic assessment could not discriminate between the 2 groups. After a median follow-up of 98 mo (range, 77-132 mo), metabolic responders (ΔTLG-early ≥ 59.5%) demonstrated a significantly higher 10-y progression-free survival (89.3% vs. 63.6%, P = 0.02) and cancer-specific survival (92.9% vs. 72.6%, P = 0.04) than incomplete metabolic responders. Conclusion: Our results suggest that early metabolic response can act as a surrogate marker of the benefit of antiangiogenic therapy. The findings provide further support for the use of early 18 F-FDG PET/CT evaluation to predict pathologic response and survival in the preoperative treatment of patients with locally advanced rectal cancer. ΔTLG-early showed the best accuracy in predicting tumor regression and may be particularly useful in guiding treatment-modifying decisions during preoperative chemoradiotherapy based on expected response., (© 2019 by the Society of Nuclear Medicine and Molecular Imaging.)

Thyroid carcinoma with distant metastases at initial presentation, is uncommon. Skull metastases occur very rarely, with a reported incidence of 2.5-5.8%. Here we report two cases of follicular thyroid cancer with skull involvement, and describe the diagnostic and therapeutic approach to metastatic thyroid cancer. We present the cases of a 70-year-old female and a 74-year-old female who presented with painless, large slow-growing masses of the skull. The patients underwent surgical excision of the skull masses, which were histologically diagnosed as metastatic follicular thyroid cancer, and total thyroidectomy, which confirmed the diagnosis of follicular thyroid carcinoma. They were treated with radioiodine and suppressive levothyroxine, which achieved local control of the disease. Management of metastatic thyroid cancer, requires a multidisciplinary approach and multimodality treatment. Distant metastases should be surgically removed whenever possible. Initial aggressive treatment is crucial in the management of metastatic thyroid carcinoma, providing the best chance to prolong patient survival.