[Diagnostic performance of bone scintigraphy and (11)C-Choline PET/CT in the detection of bone metastases in patients with biochemical recurrence of prostate cancer]. / Rendimiento diagnóstico de la gammagrafía ósea y la PET/TAC con (11)C-colina en la detección de metástasis óseas en pacientes con recidiva bioquímica de cáncer de próstata.

AIM: To compare bone scan (BS) with (11)C-Choline PET/CT for the detection of bone metastases in patients with biochemical recurrence of prostate cancer (PC). MATERIAL AND METHODS: A total of 169 patients with biochemical recurrence of PC(PSA:2.4-58 ng/ml) who were referred for both exams (0-15 days-in-between) were included. Lesion-detection-rate per patients and lesions were analyzed for both BS and (11)C-Choline PET/CT. Metastasis diagnosis was reached by: biopsy, CT/(18)F-Fluoride PET/MRI confirmation, or evidence of progression in subsequent imaging procedures. RESULTS: A total of 91 lesions were found to be active in BS and/or (11)C-choline PET/CT (40 patients), with 78 of which were metastatic. BS detected 38 blastic, 2 lytic and 10 non-CT-evident lesions. (11)C-Choline PET/CT detected 41 blastic, 4 lytic and 29 non-CT-evident lesions. BS and (11)C-Choline PET/CT sensitivities were 65.4% and 96.1%; specificities ere 38.5 and 92.3% (χ(2) 8.27, p<0.04). Both imaging techniques were negative in 118 patients. Tracer avid lesions were found in 51 patients: with 30/51 being BS and (11)C-Choline PET/CT concordant; in 21/51 patients had discordant lesions (kappa 0.712, p=0.00). Lesions were absolutely discordant in 10/19 patients,: 5 FN BS, 2 FP BS (degenerative changes; dysplasia), 1 FN (11)C-Choline PET/CT (blastic), 1 FP (11)C-Choline PET/CT (degenerative), 1 out of field-of-view lesion with (11)C-Choline PET/CT (tibia alone). (11)C-Choline PET/CT showed extraosseous involvement in 26/51 patients with bone metastases: 9 local recurrences, 5 infra-diaphragmatic-lymph-nodes, 2 supra-diaphragmatic, 5 local and infra-diaphragmatic, 4 infra- and supra-diaphragmatic, 1 supra-diaphragmatic and lung metastases. CONCLUSION: (11)C-Choline PET/CT yielded better sensitivity and specificity than BS for the detection of bone involvement in patients with biochemical recurrence of PC and allowed extraosseous restaging, with an impact in the clinical management of these patients.

Impacto de una TAC en inspiración adicional al protocolo convencional de la PET-TAC con 18F-FDG en la detección de nódulos pulmonares de pequeño tamaño / Impact of an additional inspiration CT scan on the conventional protocol of the 18F-FDG PET-CT in the detection of small pulmonary nodes

Objetivo. Determinar el impacto de una TAC en inspiración adicional al protocolo convencional de la PET-TAC con 18F-FDG en la detección de nódulos pulmonares de pequeño tamaño. Método. Hemos estudiado consecutivamente 100 pacientes que presentaban uno o varios nódulos pulmonares radiológicos. A todos los pacientes se les practicó un PET/TAC (Gemini, Philips). Los parámetros de adquisición fueron los mismos para la TAC no inspiratoria/fusión y la TAC en inspiración: 120kV, 25mAs. Resultados. Un total de 188 nódulos fueron detectados en la TAC inspiratoria, con tamaño entre 0,3 y 3cm. Resultados. La TAC no inspiratoria no evidenció 20/188 nódulos (10,6%) con tamaño entre 0,3 y 1cm: correspondiendo a 17 pacientes. La localización más frecuente en la que no se evidenciaron nódulos en la TAC fue en lóbulos inferiores. Resultados. La PET visualizó hipercaptación de 18F-FDG en el 83,9% y el 72% de los nódulos >1cm y entre 0,7 y 1cm, respectivamente. Sin embargo, únicamente el 10,5% de los nódulos <0,7cm mostraron aumento de actividad metabólica. Conclusiones. En pacientes seleccionados, la práctica de una TAC inspiratoria adicional al estudio PET/TAC aumenta de forma significativa la detección de pequeños nódulos pulmonares (10,6%), especialmente de los localizados en lóbulos inferiores, debido a los movimientos respiratorios y puede tener un impacto en el manejo del paciente(AU)

Aim. To determine the impact of an additional inspiration CT scan on the conventional 18F-FDG PET-CT protocol in the detection of small pulmonary nodules. Method. One hundred consecutive patients who presented with one or various nodules were studied. Whole-body PET-CT was performed using Gemini (Philips). CT acquisition parameters were 120Kv/25mAs, the same as those for the transmission/fusion CT (mild expiration) and inspiratory CT. Results. A total of 188 nodules were detected in the inspiratory CT with sizes between 0.3–3cm. Non-inspiratory CT did not show 20/188 nodules (10.6%) with sizes between 0.3–1cm, this corresponding to 17 patients. The most frequent localization of non-detectable nodules in non-inspiratory CT was the lower lobes.18F-FDG uptake was detected by the PET in 83.9% and 72% of nodules with >1cm and between 0.7 and 1cm, respectively. However, only 10.5% of nodules <0.7cm showed increased metabolic activity. Conclusion. In selected patients, inspiratory CT added to conventional PET-CT significantly improves the detection of small nodules (10.6%), especially in those lesions located in the lower lobes, due to respiratory movements, and may have an impact on patient management(AU)

[Impact of an additional inspiration CT scan on the conventional protocol of the ¹8F-FDG PET-CT in the detection of small pulmonary nodes]. / Impacto de una TAC en inspiración adicional al protocolo convencional de la PET-TAC con (18)F-FDG en la detección de nódulos pulmonares de pequeño tamaño.

AIM: To determine the impact of an additional inspiration CT scan on the conventional ¹8F-FDG PET-CT protocol in the detection of small pulmonary nodules. METHOD: One hundred consecutive patients who presented with one or various nodules were studied. Whole-body PET-CT was performed using Gemini (Philips). CT acquisition parameters were 120 kV/25 mAs, the same as those for the transmission/fusion CT (mild expiration) and inspiratory CT. RESULTS: A total of 188 nodules were detected in the inspiratory CT with sizes between 0.3-3 cm. Non-inspiratory CT did not show 20/188 nodules (10.6%) with sizes between 0.3-1cm, this corresponding to 17 patients. The most frequent localization of non-detectable nodules in non-inspiratory CT was the lower lobes. ¹8F-FDG uptake was detected by the PET in 83.9% and 72% of nodules with > 1 cm and between 0.7 and 1cm, respectively. However, only 10.5% of nodules <0.7 cm showed increased metabolic activity. CONCLUSION: In selected patients, inspiratory CT added to conventional PET-CT significantly improves the detection of small nodules (10.6%), especially in those lesions located in the lower lobes, due to respiratory movements, and may have an impact on patient management.

[Pregnancy-specific beta-1 glycoprotein (SP1) as a marker for tumors with or without trophoblastic character]. / La beta-1 glicoproteina específica del embarazo (SP1) como marcador de los tumores de naturaleza trofoblástica o no.

The pregnancy specific beta-1-glycoprotein (SP1) was measured by radioimmunoassay in 854 persons (control group 103, non-tumoral diseases 212, germinal tumors 30, and non-germinal tumors 509). Amounts higher than 2.5 ng/ml (upper normal limit) were observed in 35 cases with non tumoral diseases (specially chronic liver diseases), 97 of the non-germinal tumors (specially mammary, respiratory and digestive tumors), and 10 of the germinal tumors (pure and mixed choriocarcinomas, and embryonic carcinoma with yolk sac component). SP1 rarely is higher than 5 ng/ml in non-tumoral diseases and non-germinal tumors, while it is higher than 5 ng/ml in germinal tumors. SP1 is a good marker for trophoblastic neoplasms and shows a correlation with HCG-beta.

[Creatine phosphotransferase, B subunit, as a tumor marker. Preliminary results]. / La creatinfosfotransferasa, subunidad B, como marcador tumoral. Resultados preliminares.

Creatine kinase B (CK-B) was evaluated as a tumor marker by radioimmunoassay determination of the isoenzyme in 518 persons (control group, malignant tumors, and several other diseases). Amounts higher than 8 ng/ml (upper normal limit) was observed in 12.6 per 100 of the digestive tumors, 6.1 per 100 of the mammary tumors, 37.7 per 100 of the respiratory tumors, and 22.2 per 100 of the prostatic tumors. A relation exists between CK-B and sigmoid flexure, liver, pancreas and esophagus tumors, between CK-B and acid phosphatase in prostate tumors, and between CK-B and evolution of digestive tumor. The determination of CK-B is useful in the case of tumors lacking known tumor markers, and also as a complementary sign in the diagnosis and evolution of sigmoid flexure and prostate neoplasms.