Functional imaging in neuroendocrine tumors: assessment of molecular heterogeneity using [68Ga]Ga-DOTA-TOC and [18F]FDG PET/CT.

OBJECTIVE: The aim of the study was evaluate the diagnostic performance of [68Ga]Ga-DOTA-TOC and [18F]FDG PET/CT in patients with histologically proven neuroendocrine tumors (NETs), as well as the correlation of the visualized findings with the tumor grade. MATERIAL AND METHODS: We included 50 patients with NETs who underwent both [68Ga]Ga-DOTA-TOC and [18F]FDG PET/TC. The pooled sensitivity of both scans was compared, as well as [68Ga]Ga-DOTA-TOC and [18F]FDG for each tumor grade (grade 1/G1, grade 2/G2 and grade 3/G3). Also, the sensitivity of [68Ga]Ga-DOTA-TOC and [18F]FDG as a function of the continuous variable Ki-67 was investigated. Finally, the number of lesions detected by both PET radiopharmaceuticals for each tumor grade was compared. RESULTS: The pooled sensitivity of both PET/CT (96%) was higher than [68Ga]Ga-DOTA-TOC (84%) and [18F]FDG (44%) separately, with statistically significant differences. The sensitivity of [68Ga]Ga-DOTA-TOC was higher than [18F]FDG in both G1 (p = 0.004) and G2 (p < 0.001). In G3 the performance of both scans detected disease in 100% of this subgroup. The sensitivity of [68Ga]Ga-DOTA-TOC and [18F]FDG PET/CT correlated significantly with the Ki-67 proliferative index. In G2 patients the number of lesions detected with [68Ga]Ga-DOTA-TOC was higher than [18F]FDG. CONCLUSIONS: The performance of both PET/CT, particularly in G2 and G3, demonstrates the molecular heterogeneity of metastatic NETs and contributes to the selection of a more appropriate treatment, particularly in those high-grade patients who may benefit from radionuclide therapy (PRRT).

Role of systemic inflammatory factors in gastroenteropancreatic neuroendocrine tumors (GEP-NETs) treated with peptide receptor radionuclide therapy (PRRT): From biology to theragnosis.

AIM: Systemic inflammatory factors have been validated as indicators of ongoing systemic inflammation that could be predictive markers of poor prognosis for oncological outcomes. However, the prognostic impact of systemic inflammation markers is unknown in patients with gastroenteropancreatic neuroendocrine tumors (GEP-NETs) treated with peptide receptor radionuclide therapy (PRRT). METHODS: We conducted an observational, retrospective, multicentric study of 40 patients with GEP or unknown origin NETs treated with PRRT between 2016 and 2020. The systemic inflammatory markers were calculated as follows: neutrophil to lymphocyte ratio (NLR)=neutrophil count/lymphocyte count, monocyte to lymphocyte ratio (MLR)=monocyte count/lymphocyte count, platelet to lymphocyte ratio (PLR)=platelet count/lymphocyte count, albumin to lymphocyte ratio (ALR)=albumin levels/lymphocyte count and derived Neutrophil to Lymphocyte ratio (dNLR)=neutrophil count/(leucocytes count - neutrophils count). Baseline analysis and after the second dose were used for the calculation of different ratios. RESULTS: The median age was 63 years (range 41-85), 55% were male. The baseline cut-off values for NLR were 2.61, for MLR 0.31, for PLR 110.14, for ALR 2.39 and for dNLR 1.71. The cut-off values after the 2° dose were, for NLR 2.3, for MLR 0.3, for PLR 131.61, ALR 4.16, and dNLR 1.48. Median progression-free survival (PFS) was 21.7 months (95% CI 10.7-32.8 months) and overall survival (OS) was 32.1 months (95% CI 19.6-44.7 months), PFS was shorter in patients with elevated NLR (p=0.001), ALR (0.03), and dNLR (p=0.001) in baseline analysis. DCR was 81% and ORR 18%. CONCLUSIONS: In GEP or unknown origin NETs treated with PRRT, we have identified the predictive and prognostic impact of baseline systemic inflammatory factors.

Immunohistochemical expression of VEGFR1 in non small cell lung carcinomas: Lower VEGFR1 expression is asociated with squamous cell carcinoma subtype and high SUV max values in 18F-FDG PET.

BACKGROUND: To study the possible relation between immunohistochemical expression of vascular endothelial growth factor receptor 1 (VEGFR1) and the maximum standardised uptake value (SUV max) of 18F-FDG PET in patients with non small cell lung cancer (NSCLC). MATERIAL AND METHODS: The study included 39 patients with NSCLC (24 squamous cell carcinomas and 15 adenocarcinomas). According to the clinical stage, the patients were distributed as follows: 8 stage I, 7 stage II, 15 stage III and 9 stage IV. Immunohistochemical expression of VEGFR1 was studied through the technique of tissue-matrix using Tissue Arrayer Device (Beecher Instruments, Sun Prairie, WI), using the polyclonal antibody against VEGFR1 (Santa Cruz Biotechnology, California, USA). RESULTS: Positive VEGFR1 immunohistochemical expression was noted in 23 cases (59%). The number of positive tumours was not related with clinical stage but there was a different statistically significant association (p:0,0009) between VEGFR1 positivity and histological type, corresponding the greater percentages of positive results to adenocarcinomas (93,3%) versus in squamous cell carcinomas (37,5%). Likewise, SUV max values were higher (p: 0,039) in negative VEGFR1 carcinomas than in positive VEGFR1 tumors (r: 4-32,1; 16,4+/-6,4 (median 16,1) vs r: 3-47; 14,5+/-8,6 (12,8)). CONCLUSIONS: Our results led us to consider that in NSCLC, the negative VEGFR1 immunohistochemical expression is associated significantly with squamous cell carcinomas subtype and with higher SUV max values in 18F-FDG-PET.

18F-FDG PET/CT in cardiovascular infection and inflammation.

The diagnosis of cardiovascular infection and inflammation by [18F]FDG PET/CT in Nuclear Cardiology is of growing interest, because with respect to echocardiography this technique has improved the certainty in the diagnosis of infective endocarditis in patients with prosthetic valves, the increasing number of patients with implantable cardiac devices because of the progressive ageing of the population, as well as in patients with suspected large vessel vasculitis. All are serious clinical situations which require correct diagnosis and appropriate treatment as soon as possible, because they can cause severe complications, high mortality and also increased health care costs. We review the use of [18F]FDG PET/CT in cardiovascular infection and inflammation, including the clinical point of view and the contribution of other image modalities. We focus on the appropriate methodology for this exploration, patient preparation, image acquisition and correct interpretation and the quantification possibilities, defining the specific characteristics of the diagnosis in patients with prosthetic valves, implantable cardiac devices and large vessel vasculitis in the initial diagnosis as well as during follow-up to assess treatment response. We analyze the possible causes of false positive and false negative results and emphasize the special value of a multidisciplinary team for optimal management of these patients.

Immunohistochemical expression of VEGFR1 in non small cell lung carcinomas: Lower VEGFR1 expression is asociated with squamous cell carcinoma subtype and high max SUV values in 18F-FDG PET. / Expresión inmunohistoquímica de VEGFR1 en carcinomas de pulmón de células no pequeñas: La expresión inferior de VEGFR1 se asocia con el subtipo de carcinoma de células escamosas y los valores elevados en SUVmáx en PET de 18F-FDG.

BACKGROUND: To study the possible relation between immunohistochemical expression of vascular endothelial growth factor receptor 1 (VEGFR1) and the maximum standardised uptake value (maxSUV) of 18F-FDG PET in patients with non small cell lung cancer. MATERIAL AND METHODS: The study included 39 patients with NSCLC (24 squamous cell carcinomas and 15 adenocarcinomas). According to the clinical stage, the patients were distributed as follows: 8 stage I, 7 stage II, 15 stage III and 9 stage IV. Immunohistochemical expression of VEGFR1 was studied through the technique of tissue-matrix using tissue arrayer device (Beecher Instruments, Sun Prairie, WI), using the polyclonal antibody against VEGFR1 (Santa Cruz Biotechnology, California, USA). RESULTS: Positive VEGFR1 immunohistochemical expression was noted in 23 cases (59%). The number of positive tumours was not related with clinical stage but there was a different statistically significant association (p:.0009) between VEGFR1 positivity and histological type, corresponding the greater percentages of positive results to adenocarcinomas (93.3%) versus in squamous cell carcinomas (37.5%). Likewise, maxSUV values were higher (p: .039) in negative VEGFR1 carcinomas than in positive VEGFR1 tumors (r: 4-32.1; 16.4+/-6.4 [median 16.1] vs. r: 3-47; 14.5+/-8.6 [12.8]). CONCLUSIONS: Our results led us to consider that in NSCLC, the negative VEGFR1 immunohistochemical expression is associated significantly with squamous cell carcinomas subtype and with higher maxSUV values in 18F-FDG-PET.

Cardiac scintigraphy with 99mTc-diphosphonates in cardiac amyloidosis. / Gammagrafía cardíaca con 99mTc-difosfonatos en la amiloidosis cardíaca.

Transthyretin cardiac amyloidosis (ATTR) has traditionally been considered a rare, difficult-to-diagnose and untreatable disease. However, its prevalence is known to be greater than what was previously thought, non-invasive diagnostic methods are available, and that effective treatments are emerging. In this context, cardiac scintigraphy (CS) with 99mTc-labelled diphosphonates has aroused a noticeable surge in interest by demonstrating high sensitivity and specificity for the reliable, non-invasive diagnosis of ATTR. By way of a guide, this article aims to identify the critical components in the performance of CS that are useful in everyday clinical practice and, thus, help specialists use optimal radiopharmaceuticals, obtain the most appropriate images, interpret the results thereof, and acquaint themselves with those clinical scenarios in which it is convenient to perform CS.

Cardiac sympathetic innervation scintigraphy with 123I-meta-iodobenzylguanidine. Basis, protocols and clinical applications in Cardiology. / Gammagrafía de inervación simpática cardiaca con 123I-metayodobencilguanidina. Fundamento, protocolos y aplicaciones clínicas en Cardiología.

Imaging of cardiac sympathetic innervation is only possible by nuclear cardiology techniques and its assessment is key in the evaluation of and decision-making for patients with cardiac sympathetic impairment. This review includes the basis of cardiac sympathetic scintigraphy with 123I-meta-iodobenzylguanidine (123I-MIBG), recommended protocols, patient preparation, image acquisition and quantification, reproducibility, dosimetry, etc., and also the clinical indications for cardiac patients, mainly with regard to heart failure, arrhythmia, coronary artery disease, cardiotoxicity, including its contribution to establishing the indication for and monitoring the response to implantable cardiac devices, pharmacological treatment, heart transplantation and other.

Axillary web syndrome following sentinel node biopsy for breast cancer. / Síndrome de web axilar secundario a la biopsia selectiva del ganglio centinela en cáncer de mama.

A 49 year-old woman diagnosed with infiltrating lobular breast carcinoma, underwent a right mastectomy and sentinel node biopsy (SLNB). The resected sentinel lymph nodes were negative for malignancy, with an axillary lymphadenectomy not being performed. In the early post-operative period, the patient reported an axillary skin tension sensation, associated with a painful palpable cord. These are typical manifestations of axillary web syndrome (AWS), a poorly known axillary surgery complication, from both invasive and conservative interventions. By presenting this case we want to focus the attention on a pathological condition, for which its incidence may be underestimated by not including it in SLNB studies. It is important for nuclear medicine physicians to be aware of AWS as a more common complication than infection, seroma, or lymphoedema, and to discuss this possible event with the patient who is consenting to the procedure.

[Silent myocardial infarction diagnosed by myocardial perfusion SPECT in a young woman with systemic lupus erythematosus]. / Infarto de miocardio silente diagnosticado por SPECT de perfusión miocárdica en mujer joven con lupus eritematoso sistémico.

Premature atherosclerosis and its consequent heart disease play a crucial role in patients with systemic lupus erythematosus, even in premenopausal women. It is one of the leading causes of death in long evolution lupus. We present the case of a 42-year-old premenopausal woman, smoker, with a history of hypertension, cholecystectomy and lupus for 23 years, treated with NSAID, steroids and antimalarial drugs. The patient consulted due to chest pain on moderate efforts. Due to the suspicion of ischemic heart disease, a cardiology study was initiated, performing a myocardial perfusion SPECT. This revealed an intense and extensive anterolateral perfusion defect, with very light reperfusion in rest images, consistent with the diagnosis of acute infarction in the apical region and ischemia in the territory of the left anterior descending artery, which was confirmed later by cardiac catheterization.

[Spontaneous intracranial hypotension: the value of isotope cisternoscintigraphy using 99mTc-DTPA]. / Síndrome de hipotensión intracraneal espontánea: utilidad de la cisternogammagrafía isotópica con 99mTc-DTPA.

INTRODUCTION: Spontaneous intracranial hypotension (SIH) is an infrequent clinical entity that is found predominantly in young adults and is characterised by the presence of acute or subacute headaches that appear on standing up and subsides on lying down. CASE REPORT: A 35-year-old female with a three-month history of holocranial headaches, accompanied by dizziness and gait instability, which increase on standing up and diminish to a certain extent on lying down, associated to bilateral tinnitus. The patient's history included a slight strain made 4 months earlier, with a sudden non-irradiated pain in the back of the neck that got better spontaneously. On the basis of the clinical and radiological findings from an MRI scan of the head and neck, our service was asked to perform a cisternoscintigraphy. CONCLUSIONS: Isotope cisternoscintigraphy using 99mTc-DTPA confirmed the diagnosis of the process and enabled us to locate the CSF leak. We therefore think it advisable to highlight its value in the diagnosis of SIH syndrome so as to be able to avoid the use of other invasive complementary explorations that entail a certain degree of morbidity and mortality.

[Temporal electric stimulation and right ventricular extension in acute postero-inferior myocardial infarction. Influence on clinical characteristics and prognosis]. / Estimulación eléctrica temporal y extensión ventricular derecha en el infarto agudo de miocardio postero-inferior. Influencia sobre las características clínicas y el pronóstico.

In 386 patients with acute inferior myocardial infarction (AIMI) who were admitted to our institution from 1984 to 1990, temporary pacemaker (TP) was required in 34 patients (9%) due to disturbances in the genesis and/or conduction of the electric stimulus (Group I). The remainder, 352 AIMI, conform the Group II. Each group was divided into groups depending on the presence (Groups Ia and IIa) or absence (Groups Ib and IIb) of right ventricular necrosis (ECG criteria: ST elevation greater than 0.1 mV in a V3r and V4R). Clinical data (cardiovascular risk factors, history of myocardial infarction or angina, CPK and CK-MB peak, Killip class, atrioventricular block and right ventricular infarction) and hospital mortality rate and its cause were analyzed. The Group I patients related to Group II had significantly higher diabetes rate (p less than 0.01), CPK and CK-MB peak (p less than 0.001), Killip class (p less than 0.001), right ventricular involvement and atrioventricular block (p less than 0.001), the mortality rate equally was statistically higher (Group I, 11 patients, 31%, versus group II, 38 patients, 11%) (p less than 0.001). The Group Ia patients related to Group Ib had a higher CPK and CK-MB peak (p less than 0.001), Killip class and atrioventricular block (p less than 0.001). The mortality rate was statistically equal. The group IIb patients related to Group IIb patients had a higher CPK and CK-MB peak (p less than 0.001), without differences in the mortality rates.(ABSTRACT TRUNCATED AT 250 WORDS)

[Clinical and prognostic implications of age in acute myocardial infarct]. / Implicaciones clínicas y pronósticas de la edad en el infarto agudo de miocardio.

The purpose of this study was to evaluate the clinical characteristics and the factors related to early mortality in the acute myocardial infarction of the geriatric population. We studied 814 consecutive patients with their first acute myocardial infarction admitted to the coronary care unit at tha Hospital General de Galicia. 401 patients were older than 65 years (Group A) and 413 were younger (Group B). Group A was found a significantly lower percentage of males (64.7% versus 88.4%; p less than 0.001) and smokers (46.7% versus 72.7%; p less than 0.001; and older patients showed a greater incidence of diabetes mellitus (28.1% versus 15.2%; p less than 0.001) and arterial hypertension (45.6% versus 31.7%; p less than 0.01). In the geriatric population, the clinical course of the acute myocardial infarction is characterized by a greater incidence of heart failure (35.3% versus 11.1%; p less than 0.001), cardiogenic shock (18% versus 5.7%; p less than 0.001) and post-acute myocardial infarction angina pectoris (18.3% versus 12.2%; p less than 0.05). Early mortality (first month) was significantly higher in elderly patients (22.7% versus 6.3%; p less than 0.001). The multivariate analysis by stepwise logistic regression identified cardiogenic shock, age and heart failure as the only independent predictive variables for early mortality. We conclude that early mortality in the acute myocardial infarction is high and related to severe degrees of pump failure and age.