Surgery and radioembolization of liver tumors.

Surgical resection is considered the curative treatment par excellence for patients with primary or metastatic liver tumors. However, less than 40% of them are candidates for surgery, either due to non-modifiable factors (comorbidities, age, liver dysfunction…), or to the invasion or proximity of the tumor to the main vascular requirements, the lack of a future liver remnant (FLR) adequate to maintain postoperative liver function, or criteria of tumor size and number. In these last factors, hepatic radioembolization has been shown to play a role as a presurgical tool, either by hypertrophy of the FLR or by reducing tumor size that manages to reduce tumor staging (term known as "downstaging").

Hospital-based proton therapy implementation during the COVID pandemic: early clinical and research experience in a European academic institution.

Introduction: A rapid deploy of unexpected early impact of the COVID pandemic in Spain was described in 2020. Oncology practice was revised to facilitate decision-making regarding multimodal therapy for prevalent cancer types amenable to multidisciplinary treatment in which the radiotherapy component searched more efficient options in the setting of the COVID-19 pandemic, minimizing the risks to patients whilst aiming to guarantee cancer outcomes.

Methods: A novel Proton Beam Therapy (PBT), Unit activity was analyzed in the period of March 2020 to March 2021.

F-fluorodeoxyglucose positron emission tomography/computed tomography (F-FDG PET/CT) predictive score for complete resection in primary cytoreductive surgery.

Objective: To assess the value of preoperative F-fluorodeoxyglucose positron emission tomography/computed tomography (F-FDG PET/CT) scan, combined with clinical variables, in predicting complete cytoreduction in selected patients with advanced ovarian cancer.

Methods: We carried out a multicenter, observational, retrospective study evaluating patients who underwent primary cytoreductive surgery for advanced ovarian cancer in two Spanish centers between January 2017 and January 2022. Inclusion criteria were histological confirmation of invasive epithelial ovarian carcinoma; preoperative International Federation of Gynecology and Obstetrics (FIGO) stage III or IV; upfront cytoreductive surgery; and F-FDG PET/CT performed 1 month prior to surgery.

C-Methionine PET/CT in Assessment of Multiple Myeloma Patients: Comparison to F-FDG PET/CT and Prognostic Value.

Multiple myeloma (MM) is the second most common haematological malignancy and remains incurable despite therapeutic advances. F-FDG (FDG) PET/CT is a relevant tool MM for staging and it is the reference imaging technique for treatment evaluation. However, it has limitations, and investigation of other PET tracers is required.

The joint use of Tc-MAA-SPECT/CT and cone-beam CT optimizes radioembolization planning.

Purpose: To determine which imaging method used during radioembolization (RE) work-up: contrast-enhanced computed tomography (CECT), Tc-MAA-SPECT/CT or cone beam-CT (CBCT), more accurately predicts the final target volume (TgV) as well as the influence that each modality has in the dosimetric calculation.

Methods: TgVs from Tc-MAA-SPECT/CT, CECT and CBCT were consecutively obtained in 24 patients treated with RE and compared with Y PET/CT TgV. Using the TgVs estimated by each imaging modality and a fictitious activity of 1 GBq, the corresponding absorbed doses by tumor and non-tumoral parenchyma were calculated for each patient.

A proof-of-concept study of the in-vivo validation of a computational fluid dynamics model of personalized radioembolization.

Radioembolization (RE) with yttrium-90 (Y) microspheres, a transcatheter intraarterial therapy for patients with liver cancer, can be modeled computationally. The purpose of this work was to correlate the results obtained with this methodology using in vivo data, so that this computational tool could be used for the optimization of the RE procedure. The hepatic artery three-dimensional (3D) hemodynamics and microsphere distribution during RE were modeled for six Y-loaded microsphere infusions in three patients with hepatocellular carcinoma using a commercially available computational fluid dynamics (CFD) software package.

Impact of the dosimetry approach on the resulting Y radioembolization planned absorbed doses based on Tc-MAA SPECT-CT: is there agreement between dosimetry methods?

Background: Prior radioembolization, a simulation using Tc-macroaggregated albumin as Y-microspheres surrogate is performed. Gamma scintigraphy images (planar, SPECT, or SPECT-CT) are acquired to evaluate intrahepatic Y-microspheres distribution and detect possible extrahepatic and lung shunting. These images may be used for pre-treatment dosimetry evaluation to calculate the Y activity that would get an optimal tumor response while sparing healthy tissues.

Evaluation of the role of thyroid scintigraphy in the differential diagnosis of thyrotoxicosis.

Objective: A differential diagnosis of thyrotoxicosis is crucial as the treatment of the main causes of this condition can vary significantly. Recently published diagnostic guidelines on thyrotoxicosis embrace the presence of thyrotropin receptor (TSH-R) antibodies (TRAb) as the primary and most important diagnostic step. The application of diagnostic algorithms to aid in the treatment of hyperthyroidism supports using thyroid radionuclide scintigraphy (TRSt) in baffling clinical scenarios, when TRAb are absent or when third-generation TRAb are not available.

The Pattern of Progression Defines Post-progression Survival in Patients with Hepatocellular Carcinoma Treated with SIRT.

Purpose: In patients with advanced hepatocellular carcinoma (HCC) treated with sorafenib, post-progression survival (PPS) is marked by the pattern of progression. Our aim was to assess the influence of the pattern of progression to selective internal radiotherapy (SIRT) in PPS among patients with HCC.

Methods: A retrospective analysis of patients treated with SIRT between 2003 and 2015 was conducted, excluding those with a single nodule < 5 cm or with metastases.

Significant dose reduction is feasible in FDG PET/CT protocols without compromising diagnostic quality.

Purpose: To reduce the radiation dose to patients by optimizing oncological FDG PET/CT protocols.

Methods: The baseline PET/CT protocol in our institution for oncological PET/CT examinations consisted of the administration of 5.18 MBq/kg of FDG and a CT acquisition with a reference current-time product of 120 mAs.

Is a Technetium-99m Macroaggregated Albumin Scan Essential in the Workup for Selective Internal Radiation Therapy with Yttrium-90? An Analysis of 532 Patients.

Purpose: To determine if baseline patient, tumor, and pretreatment evaluation characteristics could help identify patients who require technetium-99m (Tc) macroaggregated albumin (Tc MAA) imaging before selective internal radiation therapy (SIRT).

Materials And Methods: In this retrospective analysis, 532 consecutive patients with primary (n = 248) or metastatic (n = 284) liver tumors were evaluated between 2006 and 2015. Variables were compared between patients in whom Tc MAA imaging results contraindicated/modified SIRT administration with yttrium-90 (Y) resin microspheres and those who were treated as initially planned.

Effective dose estimation for oncological and neurological PET/CT procedures.

Background: The aim of this study was to retrospectively evaluate the patient effective dose (ED) for different PET/CT procedures performed with a variety of PET radiopharmaceutical compounds. PET/CT studies of 210 patients were reviewed including Torso (n = 123), Whole body (WB) (n = 36), Head and Neck Tumor (HNT) (n = 10), and Brain (n = 41) protocols with FDG (n = 170), C-CHOL (n = 10), FDOPA (n = 10), C-MET (n = 10), and F-florbetapir (n = 10). ED was calculated using conversion factors applied to the radiotracer activity and to the CT dose-length product.

MRI fused with prone FDG PET/CT improves the primary tumour staging of patients with breast cancer.

Objective: Our aim was to evaluate the diagnostic accuracy of magnetic resonance imaging (MRI) fused with prone 2-[fluorine-18]-fluoro-2-deoxy-D-glucose (FDG) positron emission tomography (PET) in primary tumour staging of patients with breast cancer.

Methods: This retrospective study evaluated 45 women with 49 pathologically proven breast carcinomas. MRI and prone PET-CT scans with time-of-flight and point-spread-function reconstruction were performed with the same dedicated breast coil.

Assessment of indeterminate pulmonary nodules detected in lung cancer screening: Diagnostic accuracy of FDG PET/CT.

Background: A major drawback of lung cancer screening programs is the high frequency of false-positive findings on computed tomography (CT). We investigated the accuracy of selective 2-[fluorine-18]-fluoro-2-deoxy-d-glucose (FDG) Positron Emission Tomography/Computed Tomography (PET/CT) scan in assessing radiologically indeterminate lung nodules detected in lung cancer screening.

Methods: FDG PET/CT was performed to characterize 64 baseline lung nodules >10mm and 36 incidence nodules detected on low-dose CT screening in asymptomatic current or former smokers (83 men, age range 40-83 years) at high risk for lung cancer.

Brain PET imaging optimization with time of flight and point spread function modelling.

Purpose: To assess the influence of reconstruction algorithms and parameters on the PET image quality of brain phantoms in order to optimize reconstruction for clinical PET brain studies in a new generation PET/CT.

Methods: The 3D Hoffman phantom that simulates (18)F-fluorodeoxyglucose (FDG) distribution was imaged in a Siemens Biograph mCT TrueV PET/CT with Time of Flight (TOF) and Point Spread Function (PSF) modelling. Contrast-to-Noise Ratio (CNR), contrast and noise were studied for different reconstruction models: OSEM, OSEM + TOF, OSEM + PSF and OSEM + PSF + TOF.