BNCT research activities at the Granada group and the project NeMeSis: Neutrons for medicine and sciences, towards an accelerator-based facility for new BNCT therapies, medical isotope production and other scientific neutron applications.

The Granada group in BNCT research is currently performing studies on: nuclear and radiobiological data for BNCT, new boron compounds and a new design for a neutron source for BNCT and other applications, including the production of medical radioisotopes. All these activities are described in this report.

False positive in fluorodeoxyglucose-F18 positron emission tomography computed tomography scan of inferior vena cava leiomyoma in patient with a suspected paraganglioma. / Falso positivo en estudio de tomografía de emisión de positrones con fluorodesoxiglucosa-F18 de un leiomioma de vena cava inferior en paciente con sospecha de paraganglioma.

Leiomyomas are benign tumors derived from smooth muscle tissue that rarely present outside the uterus. These tumors do not usually show FDG uptake. We present the case of a patient with hypertension refractory to treatment and a lesion arising from inferior vena cava, that shows intense FDG uptake in PET/CT scan, suggestive of paraganglioma, with a final histological diagnosis of leiomyoma.

125I radioactive seed localization for non-palpable lesions in breast cancer. / Semillas de 125I en la localización de lesiones no palpables en pacientes con cáncer de mama.

AIM: Marking of non-palpable breast lesions with 125I radioactive seeds is an alternative to the use of the surgical wire. The objective of this work is to present the results that we have obtained using radioactive seed localization compared to the reference technique in our center, the wire localization of non-palpable breast lesions. MATERIAL AND METHOD: Longitudinal prospective study that includes patients with histological diagnostic of breast cancer, with non-palpable lesions that are candidates to primary surgical treatment by radioactive seed localization (2016-2018) and by wire localization (2015-2016). Histological analysis of the surgical specimen was performed determining the status of surgical margins. The volume of the surgical specimen was calculated. RESULTS: A total of 146 patients were included, 95 who underwent surgery by radioactive seed localization and 51 by wire localization. The mean cube volume of the specimens were 135.67cm3 vs. 190.77cm3 (p=0.017), respectively. Eleven patients who underwent surgery by radioactive seed localization showed affected margins of the specimen (11.6%), versus 7 (13.2%) of wire localization group (p=0.084). Reintervention was performed in 9 of the patients marked with seeds and in 7 marked with wires (p=0.49). CONCLUSION: The use of 125I radioactive seeds is feasible in non-palpable breast lesions, with a low rate of reintervention and volumes of surgical specimens significantly lower than those obtained by wire localization.

Development of a positron emission tomography risks map. / Desarrollo de un mapa de riesgos para la tomografía por emisión de positrones.

Patient safety is an essential component of quality of care, especially when the complexity of care has reached extreme levels. Currently achieving this safety is considered a basic strategy of the National Health System. Nuclear Medicine departments have certain peculiarities that make them special in terms of patient safety, with situations that go beyond the common healthcare practice of other departments. Namely, that both encapsulated and non-encapsulated ionizing radiation is used in daily practice, and numerous groups of professionals must be coordinated to undertake positron emission tomography (PET) specifically, from the clinical management unit itself, and from other departments of the hospital (as well as companies outside the hospital itself and the Public Health System). The objective of this paper was to identify the risks to which a patient who is to be explored through PET can be exposed in a Nuclear Medicine department and draw up a risk map for the PET process. The methodology used is part of the proposal of the Ministry of Health (2007), and its practical implementation (given the limited literature available on Nuclear Medicine), follows as far as possible that of related care areas (radiodiagnosis and radiotherapy). For this purpose, a multidisciplinary team of professionals directly related to the PET process was created, using the modal analysis of faults and effects methodology to identify possible failures, their causes and the potential adverse events causing each. As a final step, a risk map was created, locating the previously identified faults at each stage of the process. This paper exposes the PET process, and describes the risks that patients might run when a PET scan is required, as well as the adverse events deriving from it. All this is shown in a risk map of the PET process.

Role of PET-CT with 18F-fluorocholine in biochemical recurrence after treatment of prostate cancer with curative intent. / Papel de la tomografía por emisión de positrones-tomografía computerizada con 18F-fluorocolina en la recidiva bioquímica tras tratamiento con intención curativa del cáncer de próstata.

OBJECTIVES: To analyse the ability of the PET-CT with 18F-fluorocholine (18F-FCH) to detect disease on biochemical recurrence after treatment with curative intent. To determine the clinical variables that would be able to optimise the test's diagnostic yield. MATERIAL AND METHODS: A retrospective study of PET-CTs with 18F-fluorocholine performed on 61 patients with prostate cancer who had undergone treatment with curative intent and met the criteria for biochemical recurrence. The results of the PET-CT were categorised into positive or negative and were validated using pre-established criteria. The relationship between the result of the PET-CT and the initial PSA nadir, PSA trigger, rising PSA velocity (PSAva) and PSA doubling time (PSAdt). The relationship between the metastatic sites on the PET-CT and the remaining variables was analysed. RESULTS: There was a 34.4% detection rate of the disease. The initial PSA, PSA nadir, PSA trigger and PSAva showed statistically significant differences according to the result of the PET-CT. The best discriminatory cut-off point between a positive or negative PET-CT for PSA trigger and PSAva was 3.5ng/ml and 0.25ng/ml/month respectively. The PSAdt was significantly lower in patients with remote disease compared to patients with localised disease (5.1 vs 16.8 months, P=.01). The probability that the PET-CT would detect remote disease vs localised disease was 3.2 times higher if the PSAdt was under 6 months (80% vs 20%, OR: 3.2, P=.02). In the multivariate analysis, only the initial PSA and not having undergone radical prostatectomy were demonstrated as independent predictive factors of a positive PET-CT result. CONCLUSIONS: The PET-CT with 18F-FCH can detect disease in a high percentage of patients with biochemical recurrence and provides information on its anatomical location. PSA kinetics and the patient's previous treatment are key variables in increasing the test's diagnostic.

The role of early 18F-FDG PET/CT in therapeutic management and ongoing risk stratification of high/intermediate-risk thyroid carcinoma.

Little is known about the role in ongoing risk stratification of fluorine-18-fluorodeoxyglucose positron emission tomography/computed tomography (18F-FDG PET/CT) performed early after radioactive iodine (RAI) ablation in differentiated thyroid carcinoma (DTC). The aim of the study is to investigate whether 18F-FDG PET/CT performed early after RAI ablation is useful to detect disease and to influence therapy and ongoing risk stratification. Patients with high/intermediate risk of recurrent DTC were included. 18F-FDG PET/CT scan was performed within 6 months after RAI ablation. We confirmed results with other imaging techniques, pathology reports, or follow-up. We classified the patient response as excellent, acceptable, or incomplete. Modified Hicks criteria were used to evaluate clinical impact. We included 81 patients with high/intermediate risk of recurrent DTC. Forty-one (50.6%) had positive uptake in 18F-FDG PET/CT, with negative (131)I whole-body scan ((131)I WBS). Sensitivity, specificity, and diagnostic accuracy of 18F-FDG PET/CT were 92.5, 90.2, and 91.4%, respectively. 18F-FDG PET/CT results had an impact on therapy in 38.3% of patients. One year after initial therapy, 45.7% showed excellent response, 8.6% acceptable response, and 45.7% incomplete response. A statistically significant relationship was found between negative 18F-FDG PET/CT and excellent response (80 vs. 12.2%, p < 0.001; OR 52.8). 18F-FDG PET/CT scan performed early in surveillance of patients with high/intermediate-risk thyroid carcinoma provides important additional information not available with conventional follow-up methods and had a high impact on therapy. A negative 18F-FDG PET/CT predicts an excellent response to therapy in the new ongoing risk stratification.

[Regional cerebral blood flow-SPECT "OFF-ON": a case report of catatonia]. / SPECT-perfusión cerebral regional «off-on¼: a propósito de un caso de catatonia.

We report the case of a patient with a long history of dysthymia and major depressive episodes requiring repeated hospitalization. We describe the most recent episode, associated with catatonia symptomatology and features suggestive of cognitive impairment. The absence of a clear initial psychopharmacological response alongside the clinical severity made the patient a potential candidate for electroconvulsive therapy (ECT). A regional cerebral blood flow SPECT (SPECT-rCBF), performed to rule out concomitant Alzheimer disease (AD), revealed a markedly decreased neocortical uptake, with no definitive pattern of concomitant primary cognitive impairment. Because a gradual clinical improvement was observed in the patient, with evidence of enhanced cerebral reperfusion in a second SPECT-rCBF study at two weeks after admission, the application of ECT was discounted and an expectant attitude was adopted.

The role of positron emission tomography/computed tomography imaging with radiolabeled choline analogues in prostate cancer.

INTRODUCTION: prostate cancer is the most frequent solid malignant tumor in Western Countries. Positron emission tomography/x-ray computed tomography imaging with radiolabeled choline analogues is a useful tool for restaging prostate cancer in patients with rising prostate-specific antigen after radical treatment (in whom conventional imaging techniques have important limitations) as well as in the initial assessment of a selected group of prostate cancer patients. For this reason a literature review is necessary in order to evaluate the usefulness of this imaging test for the diagnosis and treatment of prostate cancer. EVIDENCE ACQUISITION: a MEDLINE (PubMed way) literature search was performed using the search parameters: «Prostate cancer¼ and «Choline-PET/CT¼. Other search terms were «Biochemical failure¼ and/or «Staging¼ and/or «PSA kinetics¼. English and Spanish papers were selected; original articles, reviews, systematic reviews and clinical guidelines were included. CONCLUSIONS: according to available data, radiolabeled choline analogues plays an important role in the management of prostate cancer, especially in biochemical relapse because technique accuracy is properly correlated with prostate-specific antigen values and kinetics. Although is an emerging diagnostic technique useful in treatment planning of prostate cancer, final recommendations have not been submitted.

Sentinel lymph node biopsy in patients with operable breast cancer treated with neoadjuvant chemotherapy.

AIM: To evaluate the accuracy of sentinel lymph node biopsy (SLNB) in operable breast cancer patients treated with neoadjuvant chemotherapy (NAC). MATERIALS AND METHODS: Between January 2008-2011, 88 women, mean age 49.4 years, with infiltrating breast carcinoma, were studied prospectively. Patients were T1-3, N0-1, M0. Prior to surgery, the patients received chemotherapy (epirubicin/cyclophosphamide, docetaxel), and trastuzumab in Her2/neu-positive patients. Axillary status was established by physical examination, ultrasound-guided core needle biopsy of any suspicious lymph node. The day before surgery, 74-111 MBq of (99m)Tc-albumin nanocolloid was injected periareolarly. All patients underwent breast surgery, with SLNB, followed by complete axillary lymph node dissection (ALND). Sentinel lymph node (SLN) were examined by frozen sections, hematoxylin-eosin staining and immunohistochemical analysis or One Step Nucleic Acid Amplification (OSNA). RESULTS: Mean tumor size: 3.5 cm. Histologic type: 69 invasive ductal, 16 invasive lobular and 3 others. Thirty seven patients had clinical/ultrasound node-positive at presentation. Clinical response of primary tumor to NAC: complete in 38, partial in 45, and stable disease in 5 patients. A pathological complete response was achieved in 25. All patients were clinically node-negative after NAC. SLN identification rate was 92.0%. Six of 7 patients in whom SLN was not found had clinical/ultrasound positive axilla before NAC. SLN accurately determined the axillary status in 96.5%. False negative rate was 8.3%. In 69.4% of patients, SLN was the only positive node. The mean number of SLN removed was 1.7 and nodes resected from the ALND were 13.2. CONCLUSION: SLN biopsy after NAC can predict the axillary status with a high accuracy in patients with breast cancer, avoiding unnecessary ALND.

Tomografía por emisión de positrones con 18F-fluorodesoxiglucosa en la evaluación preoperatoria de lesiones de vesícula biliar sospechosas de malignidad. Utilidad diagnóstica e impacto clínico / fgfg

Introducción. El cáncer de vesícula (CV) es una neoplasia de mal pronóstico en la que el empleo de la tomografía por emisión de positrones (PET) con 18F-fluorodesoxigluosa (FDG) como herramienta diagnóstica puede ser útil, aunque su papel no está bien definido. Diseño/metodología. Cohorte prospectiva de pacientes con lesión radiológica vesicular sospechosa de malignidad en estudio de diagnóstico y estadificación prequirúrgico mediante PET-FDG en equipos convencionales (PET) y equipos multimodalidad (PET-TAC). Estimación de validez diagnóstica contrastando los resultados de ambos procedimientos con el estudio histopatológico y/o la evolución clínica de los pacientes. Análisis del impacto clínico derivado de su implantación en el diagnóstico del CV. Resultados. Se reclutaron 42 pacientes, 22 con resultado histológico de malignidad y 20 de benignidad. La precisión diagnóstica global fue del 83,33% para el diagnóstico oncológico de la lesión primaria, del 88,89% para la afectación ganglionar y del 85,1% para la afectación metastásica. El SUVmáx medio de las lesiones vesiculares malignas fue 6,14±2,89. La curva ROC mostró un punto de corte de SUVmáx: 3,65 para malignidad. La validez diagnóstica de la PET (n=21) fue discretamente inferior que la de la PET-TAC (n=21). La realización de la PET-FDG modificó la actitud terapéutica en el 14,8%, al encontrar enfermedad diseminada no sospechada. Comentarios. La PET-FDG diagnostica con precisión la malignidad o benignidad de una lesión vesicular sospechosa, añadiendo la capacidad de identificar enfermedad metastásica no sospechada. La PET-TAC mejora la precisión diagnóstica de la PET por la complementariedad metabólico-estructural de su información. El SUVmáx tiene un valor complementario al análisis visual(AU)

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Utilidad de la PET/TAC en la estadificación mediastínica del cáncer de pulmón de células no pequeñas en estadio III (N2) / Utility of PET/CT for mediastinal staging of non-small cell lung cancer in stage III (N2)

Objetivo. Evaluar la validez diagnóstica de la tomografía por emisión de positrones con 18F-fluoro-2-deoxi-D-glucosa y la tomografía computarizada (PET/TAC) en la estadificación ganglionar mediastínica (N2) en pacientes con cáncer de pulmón de células no pequeñas (CPCNP) y analizar el papel de la estadificación mediante pruebas invasivas para la verificación de los hallazgos de la tomografía por emisión de positrones (PET)/tomografía computerizada (TAC). Material y métodos. Estudio retrospectivo incluyendo a pacientes con diagnóstico histopatológico de CPCNP, estadificados como N2 mediante TAC+C y estudiados con PET/TAC. Se confirmaron mediante análisis histopatológico de la pieza quirúrgica cuando se dispuso o por consenso iconográfico en el comité de tumores torácicos. Se ha calculado la sensibilidad, especificidad, valor predictivo positivo y valor predictivo negativo del estudio PET/TAC en la correcta clasificación de los pacientes N2. Resultados. Se incluyeron 34 pacientes clasificados como N2 mediante TAC+C. El PET/TAC clasificó a 30 pacientes como estadio N2. Se encontraron discrepancias en 4 pacientes, dos clasificados como N1 y dos como N0. Los resultados fueron confirmados histológicamente en 20 pacientes. El estudio PET/TAC no mostró falsos positivos. La sensibilidad fue del 94,7%, la especificidad y el valor predictivo positivo fue del 100% y el valor predictivo negativo del 50%. Conclusiones. El estudio PET/TAC presenta una alta sensibilidad y valor predictivo positivo en la correcta clasificación de pacientes con afectación ganglionar mediastínica (N2). Nuestros resultados sugieren que en pacientes con cáncer de pulmón potencialmente resecable, candidatos a tratamiento con quimioterapia neoadyuvante, la mediastinoscopia podría reservarse para la re-estadificación(AU)

Purpose. To evaluate the accuracy of integrated positron emission tomography with 18F-fluoro-2-deoxy-D-glucose (FDG) and computed tomography (PET/CT) in mediastinal lymph node staging in patients with potentially operable (N2) non-small cell lung cancer (NSCLC) and to ascertain the role of invasive staging in verifying positron emission tomography (PET)/computed tomography (CT) results. Material and methods. A retrospective study of consecutive patients with pathologically-proven NSCLC and N2 staging by enhanced CT was performed. A PET/CT scan was performed for all the patients. Lymph node staging was pathologically confirmed when it was possible or by consensus in the Thoracic Cancer Committee. Sensitivity, specificity, negative predictive value and positive predictive value of PET/CT in N2 cases were determined. Results. A total of 34 patients with N2 by CT were evaluated. PET/CT showed N2 in 30 patients. Discrepancies were found in four patients, two patients were classified as N1 in PET/CT and two patients as N0. Lymph node staging was pathologically confirmed in 20 patients. No false positives were found in PET/CT study. Sensitivity was 94.7%, specificity and positive predictive values were 100% and negative predictive value was 50%. Conclusions. Our data show that integrated PET/CT provides high sensitivity and positive predictive value in mediastinal nodal staging of NSCLC patients. Therefore, in patients with potentially resectable lung cancer, neoadjuvant chemotherapy candidate, mediastinoscopy could be reserved for restaging after induction therapy(AU)

Falso negativo de la gammagrafía con 99mTc-sestamibi en un carcinoma paratiroideo con tumores pardos asociados. Aportaciones de la PET/TAC-18F-FDG / False negative of the scintigraphy with 99mTc-sestamibi in parathyroid carcinoma with associated brown tumors. Contributions of the 18F-FDG-PET/CT

El carcinoma paratiroideo (CPT) es un tumor poco frecuente que suele ser hiperfuncionante, produciendo un exceso de hormona paratiroidea. El hiperparatiroidismo produce trastornos del metabolismo óseo, como osteopenia y en ocasiones tumores pardos. Los tumores pardos son lesiones óseas benignas, pero localmente destructivas, cuyo diagnóstico diferencial con metástasis u otros tipos de tumores primarios puede ser complicado. La técnica habitual para la detección de patología paratiroidea es la gammagrafía con 99mTc-sestamibi, con una sensibilidad del 85–100% y una especificidad cercana al 100% en adenomas paratiroideos, presentando cifras muy similares en la detección del CPT. Presentamos el caso de un paciente diagnosticado de hiperparatiroidismo de origen tumoral con lesiones óseas asociadas en el que la gammagrafía con 99mTc-sestamibi presentó un falso negativo en la detección de patología paratiroidea. Sin embargo, la PET/TAC-18F-FDG detectó el CPT y ayudó en el diagnóstico diferencial de las lesiones óseas asociadas, que fueron finalmente tumores pardos(AU)

Parathyroid carcinoma (PTC) is a rare malignant disease that is usually hyperfunctioning, which produces an excess of parathyroid hormone. Hyperparathyroidism causes bone metabolism disorders, as osteopenia and sometimes brown tumors. Brown tumors are benign but locally aggressive bone lesions, whose differential diagnosis with metastases or other primary malignancies may be complicated. 99mTc-Sestamibi scan is the usual procedure for the detection of parathyroid pathology, with a sensitivity of 85–100% and specificity close to 100% in parathyroid adenomas, it having similar percentages in the detection of PTC. We present the case of a patient diagnosed of a malignant hyperparathyroidism associated with bone lesions in which the 99mTc-Sestamibi scan showed a false negative result in the detection of parathyroid condition. However, 18F-FDG-PET/CT detected the PTC and helped in the differential diagnosis of associated bone lesions, which were finally confirmed as brown tumors(AU)

[Positron tomography with 18F-fluorodeoxyglucose in the preoperative evaluation of gall bladder lesions suspicious of malignancy. Diagnostic utility and clinical impact]. / Tomografía por emisión de positrones con (18)F-fluorodesoxiglucosa en la evaluación preoperatoria de lesiones de vesícula biliar sospechosas de malignidad. Utilidad diagnóstica e impacto clínico.

BACKGROUND: Gallbladder carcinoma is a neoplasm having a poor prognosis in which the role of the positron emission tomography with (18)F-fluordeoxyglucose as a diagnostic tool, although of possible usefulness, has not been well-defined. METHODS/DESIGN: It is a prospective cohort of patients with radiologically malignant suspicious gallbladder lesions. A staging diagnostic presurgical FDG-PET study was carried out in each patient using both dedicated PET and multimodality PET-CT scanners. Diagnostic accuracy parameters were calculated from the results of PET imaging and were correlated with the condition and/or the clinical course of the patients. The clinical impact of its implementation in the diagnosis of gallbladder carcinoma was also analyzed. RESULTS: A total of 42 patients were recruited (22 malignant lesions, 20 benign). Overall diagnostic accuracy was 83.33% for the diagnosis of the primary lesion, 88.89% for the evaluation of lymph node involvement and 85.1% for the evaluation of metastatic disease. Mean SUVmax in malignant gallbladder lesions was 6.14±2.89. ROC curve showed a cut-off value of 3.65 in the SUVmax for malignancy. Accuracy of PET studies alone (n=21) was slightly lower than that of the PET/CT (n=21). FDG-PET changed the management of 14.8% of the population due to the identification of unsuspected metastatic disease. COMMENTS: FDG-PET accurately diagnoses malignancy or benignity of suspicious gallbladder lesions, with the addition of its capacity to identify unsuspected metastatic disease. PET-CT improves the diagnostic accuracy of the procedure, due to the metabolic-structural complementarity of their information. The SUVmax has a complementary value added to the visual analysis.

[Utility of PET/CT for mediastinal staging of non-small cell lung cancer in stage III (N2)]. / Utilidad de la PET/TAC en la estadificación mediastínica del cáncer de pulmón de células no pequeñas en estadio III (N2).

PURPOSE: To evaluate the accuracy of integrated positron emission tomography with (18)F-fluoro-2-deoxy-D-glucose (FDG) and computed tomography (PET/CT) in mediastinal lymph node staging in patients with potentially operable (N2) non-small cell lung cancer (NSCLC) and to ascertain the role of invasive staging in verifying positron emission tomography (PET)/computed tomography (CT) results. MATERIAL AND METHODS: A retrospective study of consecutive patients with pathologically-proven NSCLC and N2 staging by enhanced CT was performed. A PET/CT scan was performed for all the patients. Lymph node staging was pathologically confirmed when it was possible or by consensus in the Thoracic Cancer Committee. Sensitivity, specificity, negative predictive value and positive predictive value of PET/CT in N2 cases were determined. RESULTS: A total of 34 patients with N2 by CT were evaluated. PET/CT showed N2 in 30 patients. Discrepancies were found in four patients, two patients were classified as N1 in PET/CT and two patients as N0. Lymph node staging was pathologically confirmed in 20 patients. No false positives were found in PET/CT study. Sensitivity was 94.7%, specificity and positive predictive values were 100% and negative predictive value was 50%. CONCLUSIONS: Our data show that integrated PET/CT provides high sensitivity and positive predictive value in mediastinal nodal staging of NSCLC patients. Therefore, in patients with potentially resectable lung cancer, neoadjuvant chemotherapy candidate, mediastinoscopy could be reserved for restaging after induction therapy.

[False negative of the scintigraphy with 99mTc-sestamibi in parathyroid carcinoma with associated brown tumors. Contributions of the 18F-FDG-PET/CT]. / Falso negativo de la gammagrafía con 99mTc-sestamibi en un carcinoma paratiroideo con tumores pardos asociados. Aportaciones de la PET/TAC-18F-FDG.

Parathyroid carcinoma (PTC) is a rare malignant disease that is usually hyperfunctioning, which produces an excess of parathyroid hormone. Hyperparathyroidism causes bone metabolism disorders, as osteopenia and sometimes brown tumors. Brown tumors are benign but locally aggressive bone lesions, whose differential diagnosis with metastases or other primary malignancies may be complicated. (99m)Tc-Sestamibi scan is the usual procedure for the detection of parathyroid pathology, with a sensitivity of 85-100% and specificity close to 100% in parathyroid adenomas, it having similar percentages in the detection of PTC. We present the case of a patient diagnosed of a malignant hyperparathyroidism associated with bone lesions in which the (99m)Tc-Sestamibi scan showed a false negative result in the detection of parathyroid condition. However, (18)F-FDG-PET/CT detected the PTC and helped in the differential diagnosis of associated bone lesions, which were finally confirmed as brown tumors.