[Early detection with FDG-PET of colonic tumors in patients with another known tumor]. / Detección temprana con PET-FDG de tumores inesperados de colon en pacientes con otra patología tumoral conocida.

Patients with known tumors can have other tumors in unexpected places, the so-called synchronic or second primary cancers. In these patients, whole-body fluorodeoxyglucose positron emission tomography (FDG-PET) to study known tumors can identify other tumors that would escape notice if only the sites of known tumors were investigated. We present 3 patients in whom whole-body FDG-PET was requested to study known tumors: 2 lung cancers and one melanoma. FDG-PET localized the known lesions and revealed hypermetabolic uptake in the abdomen in all 3 patients. Endoscopic polypectomy and pathologic analysis were performed, revealing 2 colon cancers and a tubular adenoma with a high degree of focal atypia. Whole body FDG-PET is a highly useful technique in the early diagnosis of colorectal cancer, which in turn allows complete cure of patients with this disease.

El rastreo oseo isotópico en la fibromialgia reumática / Oseo fibromyalgia syndrome

Existen muy pocos estudios que relacionen la Fibromialgia reumática (FR) con el Rastreo Óseo Isotópico (RO). El objetivo de este trabajo es evaluar el valor del RO en el diagnóstico de la FR e intentar encontrar un patrón óseo gammagráfico que permita el diagnóstico de esta patología, al igual que sucede con otras enfermedades osteoarticulares reumáticas, ayudando también así en el diagnóstico diferencial con éstas. Se han estudiado 19 mujeres (edad 24-69 años). 14 de ellas presentaban diagnóstico clínico de FR y 5 sospecha clínica. A todas ellas se les realizó un gran número de pruebas diagnósticas: analíticas sanguíneas, Radiología convencional, Electrocardiogramas, Electroencefalogramas, Electromiografia, Ecografía, Tomografía computerizada, Resonancia magnética y RO. En todos los RO se observaron incrementos anormales de captación de intensidad variable, de localización difusa o puntual y a nivel poliarticular, además de los hallazgos ya conocidos por la patología osteoarticular concomitante de las pacientes. No se observó la presencia de fase vascular positiva en ningún caso a pesar de ser zonas dolorosas en la exploración clínica. No se observó relación entre la localización e intensidad de captación del radiofármaco y la presencia clínica de dolor.Pensamos que los pacientes con FR podrían presentar un patrón gammagráfico variable en cuanto a localización e intensidad de captación, de tipo poliarticular en fase tardía.

[Bone scintigraphy and somatostatin receptor scintigraphy in pediatric patients with bone involvement in Langerhans cell histiocytosis]. / Gammagrafía ósea y gammagrafía de receptores de la somatostatina en pacientes pediátricos con histiocitosis de células de Langerhans ósea.

Langerhans cell histiocytosis (LCH) is a granulomatous disease which can involve multiples sites of the body. Diagnostic imaging is of utmost importance in the management of these patients. Up to now radiographic skeletal survey and bone scintigraphy (BS) have been used to assess bone involvement (both with low specificity). Magnetic resonance imaging (MRI) and CT have been used to assess visceral involvement but with the limitation that they cannot give information about the functional status. Recently somatostatin receptor scintigraphy (SSRS) has been proposed to detect active lesions and to monitor response to treatment. The aim of this study is to assess bone and somatostatin receptor scintigraphy in the detection of bone involvement in LCH in children. Twenty scintigraphies (12 SSRS and 8 BS) were performed in seven patients (3 girls and 4 boys) aged at diagnosis: 18 month-12 years (mean age 6 years). The findings obtained in the scintigraphies were compared with clinical evolution and other imaging techniques. Bone scintigraphy detected all the LCH bone lesions, and discovered one unknown lesion. SSRS scintigraphy visualised the active lesions in 3 patients (clinical and other imaging techniques were also positive). SSRS was negative in one patient classified as disease free and another in clinical remission. SSRS detected 2 new unknown bone lesions, but could not detect LCH bone lesions confirmed in other imaging techniques in 2 patients. Somatostatin receptor and Bone scintigraphy can be used to detect active LCH bone lesions in children and can help to monitor response to treatment. Further studies with more patients are needed to confirm the diagnostic usefulness of these techniques.

Hodgkin's disease. Prognostic value of Gallium-67 scintigraphy.

AIM: The aim of this study is to assess the clinical impact of gallium-67 scintigraphy, before and after treatment, in patients with Hodgkin's disease, and to compare the overall survival between the patients whose gallium studies after treatment were negative and those whose studies remained positive. METHODS: We have studied 75 patients (40 women, 35 men) with Hodgkin's disease. All the patients underwent (67)Ga scintigraphy at the moment of the diagnosis (basal study) and in the case that basal study was positive (abnormal hyper-uptake focus) we performed follow-up studies after the treatment. We have calculated the overall survival among patients whose studies after treatment were negative (1(st) group) and those whose studies remained positive (2(nd) group) and between patients whose studies were negative at diagnosis (3(rd) group). RESULTS: Gallium scintigraphy was positive at diagnosis in 47 patients (62.6%). In 39 of them we were able to perform the follow-up study after treatment. The follow-up study was negative in 31 patients while in 8 patients the gallium scintigraphy remained positive. The overall survival was significantly higher (p<0.001) in the 1(st) group compared with the 2(nd) group. The overall survival was higher in the 1(st) group compared with the 3(rd) but statistic significance level was not reached. CONCLUSION: Our data suggest that: 1) in Hodgkin's disease (67)Ga scintigraphy is useful to establish the diagnosis of complete remission; 2) if the gallium scan remains positive after treatment, the prognosis of patients is worse than the prognosis of patients with a negative scan.

[Value of the use of the geometric mean to calculate the relative renal function in 99mTc-DMSA renal scintigraphy]. / Valor del uso de la media geométrica en el cálculo de la función renal relativa en la gammagrafía renal con 99mTc-DMSA.

Determining the relationship of DMSA uptake of the left versus right kidney is theoretically one of the easiest quantitative procedures in nuclear medicine. The quantification can be performed on the posterior view, with or without a lateral view for correction of kidney depth. The geometric mean can also be determined by using both the anterior and the posterior views. This study has aimed to evaluate if there are significant differences in the quantification of the renal function percentage using only the posterior view and the geometric mean. Furthermore, we evaluated to what extent the patient's age and diagnosis influenced these differences. We have proposed a work protocol in which we indicate which cases the geometric mean should be calculated in order to minimize the possible errors occurring when only the posterior view is used.A total of 328 renal scintigraphies with 99mTc-DMSA performed at our Department in the last six months were studied. The mean and standard deviation of the differences as well as the correlation coefficient between both methods were calculated. The difference between the right renal function in posterior view and the right renal function obtained using the geometric mean was calculated for all the patients. The Student's T test was applied to determine whether the differences between both methods were statistically different from zero. Statistical differences were found in patients older than 9 years and in patients with genitourinary malformations.

[Soft tissue malignant fibrous histiocytoma. Visualization in bone scintigraphy]. / Histiocitoma fibroso maligno de partes blandas. Visualización en gammagrafía ósea.

Malignant fibrous histiocytoma (MFH) is the most common soft tissue malignant tumour in late adult life. MFH has been mentioned to have avid uptake of 67Ga citrate, and only 38% is uptake of 99mTc-MDP, although few cases of MFH have been reported. We present the case of a 73 years old male patient with MFH. In the blood pool phase of the bone scintigraphy, MFH was presented as an intense hyperactive lesion. In the late phase the tumor is one of the few MFH described to have avid uptake for 99mTc-MDP. In this work we also review some cases of MFH described and the different techniques used in the diagnosis and follow-up of these tumours.

[Thyroid scintigraphy and body scanning with 67 Ga in a case of primary thyroid lymphoma]. / Gammagrafía tiroidea y rastreo corporal con 67Ga en un caso de linfoma tiroideo primario.

The case of a 60-year old woman first presented a rapidly growing left cervical mass is presented. The fine needle aspiration-puncture (FNAP) lead to a diagnosis of thyroiditis. Due to the persistence of the symptoms, the FNAP was repeated again but was not conclusive, so that a surgical biopsy was performed. The pathological diagnosis was diffuse large cell primary thyroid lymphoma (PTL). The PTL is a rare entity that accounts for less than 1% of all the Non-Hodgkin's lymphomas. The thyroid scintigraphy showed the existence of a cold nodule in the left thyroid lobule and the 67Ga scan revealed a large abnormal lesion in the mediastinum that extended to the right latero-cervical region. After two chemotherapy courses, the 67Ga scan was normal.

[Value of 123I-MIBG scanning, neuron-specific enolase and serum ferritin in the diagnosis and follow-up of patients with neuroblastoma]. / Valor del rastreo con 123I-MIBG, enolasa neuronal específica y ferritina sérica en el diagnóstico y seguimiento de pacientes con neuroblastoma.

INTRODUCTION: The neuroblastoma (NB) is one of the most common pediatric malignant neoplasms. The most commonly used tumor markers in the diagnosis and follow-up of this tumor are the serum neuron-specific enolase (NSE), ferritin and lactic dehydrogenase and urinary vanillymandelic and homovanillic acid. The common imaging modalities are CT, MRI and 123I or 131I-meta-iodobenzylguanidine scintigraphy. AIM: The aim of this study is to assess the value of 123I-meta-iodobenzylguanidine (MIBG) scintigraphy and serum determinations of NSE and ferritin in the diagnosis and evolution of NB patients. MATERIAL AND METHODS: 20 patients (8 female, 12 male) whose ages ranged from 2 months to 9 years with a mean age of 2.64 years diagnosed of NB. 47 123I-MIBG scans, 47 NSE determinations and 47 ferritin ones were selected. RESULTS: At the time of diagnosis, 100% of the 123I-MIBG scans were positive. 65% of NSE determinations presented clearly pathological levels and 15% were very near to the cut-off point. Only 45% of the ferritin levels were increased. The differences between the lesions visible by 123I-MIBG scanning before and 3 months after treatment as well as NSE and ferritin levels were studied. When the Student's T test was applied, we found statistically significant pre and post-treatment differences in 123I-MIBG scanning and NSE. In the case of ferritin, there was no statistical significance in spite of the decrease in the values. The direct correlation and Spearman correlation between laboratory data and 123I-MIBG scanning as well as correlation between NSE and ferritin were also studied. There was a good correlation between 123I-MIBG and NSE and between NSE and ferritin. We have also studied the data in 7 relapses. CONCLUSIONS: 123I-MIBG scintigraphy and serum determination of NSE are two successful diagnostic tools for the diagnosis and evolution of NB patients.

[Bone scintigraphy in two cases of primary vertebral osteosarcoma in adults]. / Gammagrafía ósea en dos casos de osteosarcoma vertebral primario en edad adulta.

The primary vertebral osteosarcoma in adults is a rare tumor which represents less than 2% of all osteosarcomas. We present the cases of two men (40 and 33 years old) who began with pain and neurological compression symptoms. The imaging methods used to study the tumors were X-rays, CT, MRI and bone scintigraphy with 99mTc-HMDP. After the pathological diagnosis, the tumors were removed surgically and the treatment was completed with chemotherapy and radiotherapy. In this report the authors review the published cases of vertebral osteosarcoma, its epidemiology, clinical presentation and characteristics in the different imaging techniques.

[Hepatobiliary scintigraphy in a case of acute cholecystitis in childhood]. / Gammagrafía hepatobiliar en un caso de colecistitis aguda en la infancia.

Acute cholecystitis is an uncommon disease in childhood. Few cases in patients under 10 years of age have been found in literature. An eight-year old male patient with no history of interest who had acute acalculous cholecystitis was reported. Ultrasonographic and isotopic studies led to the diagnosis and control of the patient's evolution.