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L Lapeña

Publications and source records attributed to L Lapeña.

8 recordsLinked to original sources
PubMed2004

[Positron emission tomography using 18-FDG-PET in radiologically indeterminate pulmonary lesions].

OBJECTIVE: Fluorine-18 deoxyglucose Positron Emission Tomography (FDG-PET) is a non-invasive technique that offers the possibility to define if the radiologically indetermined pulmonary lesions are benign or malignant with high positive and negative predictive values. Considering the indexed literature we can observe that there are few original studies performed with the diagnostic possibilities of our means. For this reason, our main objective is to evaluate the diagnostic accuracy of positron emission tomography in sixty-seven radiologically indetermined pulmonary nodular lesions. MATERIAL AND METHOD: Retrospectively, we evaluated the diagnostic ability of FDG-PET globally (by means of visual and semiquantitative analysis) and partially (only considering the Standardized Uptake Value (SUV)), in sixty-seven patients confirmed by pathology or clinical and radiological monitoring, in a time interval superior to one year. RESULTS: Globally, FDG-PET had a sensitivity (S) of 92%, specificity (SP) of 86.6%, positive predictive value (PPV) of 89.4%, negative predictive value (NPV) of 89.6% and diagnostic accuracy (DA) of 89%. The best results were obtained for an SUV equal or superior to 2.5. With this value, the clinical efficacy parameters were: S 0.92, SP 0.90, PPV 0.92, NPV 0.90 and DA 0.91. CONCLUSIONS: We can characterize most of the radiologically indetermined pulmonary lesions by FDG-PET. The additional use of SUV facilitates an increase in the positive predictive value and specificity of FDG-PET.

Adult↗
PubMed1992

[Determination of basal and stimulated blood gastrin in duodenal ulcer].

Serum gastrin levels were measured under basal conditions and after hyperproteic meal stimulation in 24 patients with non-stenotic duodenal ulcer, 78% of them were males with a mean age of 36.4 years. Results were compared with those obtained in 20 volunteers. Basal gastrin levels in patients with duodenal ulcer 46.2 +/- 17.5 pg/ml did not show any significant statistical differences when compared with those in the control group (51.01 +/- 28.1 pg/ml). After meal stimulation gastrin levels at different time intervals, were similar in patients with duodenal ulcer and in the control group. We conclude that serum gastrin does not seem to play a relevant pathogenic role in the development of duodenal ulcer; its measurement is of no value as a biological marker of duodenal ulcer disease.

Adult↗
PubMedDate not supplied

[Diagnostic accuracy of semiquantitative analysis of positron emission tomography in radiologically indeterminate lung lesions].

OBJECTIVE: The objective of this work was to assess the Standardized Uptake Value (SUV) in the differential diagnosis of radiologically indeterminate lung lesions by means of ROC curves. MATERIAL AND METHOD: Forty seven patients were studied by Positron Emission Tomography with 18-fluorine-2-desoxy-D-glucose (FDG PET) analyzing the value of maximum SUV. The patients were classified into three groups. Group 1 = patients without previous neoplasia (WPN) + patients with previous neoplasia (PN). Group 2 = WPN. Group 3 = PN. RESULTS: The ROC curves showed a high diagnostic accuracy in the three groups, with area under the curve (AUC) values of 0.96, 0.98 and 0.91 respectively. The typical error was 0.03, 0.02 and 0.08. The maximum SUV cutoffs with the best diagnostic accuracy for the three groups were: 2.6; 3 and 2.4, with an accuracy (A) of 93.6%, 97% and 92.3%, respectively. Analyzing all the patients globally (group 1), we obtained one false positive result in a patient with hamartoma (max SUV = 2.8) and two false negative results in one patient with lung metastases from malignant fibrohistiocytoma (max SUV = 0.7) and in another patient with lung metastases from unknown origin adenocarcinoma (max SUV = 1.9). CONCLUSIONS: FDG PET permits differentiation with a very high diagnostic accuracy of benign and malignant lung lesions using the maximum SUV. The differences observed between the different groups are due to the different disease prevalence, obtaining a lower negative predictive value of max SUV in patients with previous neoplasia.

Adult↗
PubMedDate not supplied

[Impact of positron emission tomography with FDG-PET in treatment of patients with suspected recurrent ovarian cancer].

AIM: Recurrent ovarian cancer is a major problem and an accurate diagnosis can often change patients' management. This study aimed to assess the impact on management of FDG-PET in recurrent ovarian cancer. MATERIAL AND METHODS: Forty-three patients in whom FDG-PET scan was performed due to suspected recurrent ovarian cancer were included. FDG-PET results were confirmed by histopathology and clinical follow-up of at least 12 months. To assess impact on management the treatment plan based on conventional imaging methods was compared with the treatment plan based on inclusion of PET findings, classifying FDG-PET impact on management as high, medium, low or no impact. Management changes, when present, were classified as intermodality or intramodality. RESULTS: FDG-PET had a high impact on therapeutic management in 28 patients (65.1 %), medium impact in 2 patients (4.6 %), low impact in 9 patients (20.9 %), and no impact in 4 patients (9.3 %). FDG-PET induced an intermodality change in management in 27 patients (62,8 %); intramodality changes were induced in 3 patients (7 %). Finally, it produced no treatment changes in 13 patients (30.2 %). CONCLUSION: FDG-PET supplied additional information when compared to conventional diagnostic procedures and allowed adequate management changes in most patients.

Adult↗
PubMedDate not supplied

[Normal values for basal serum gastrin with and without stimulation].

In the present work we report a study of the basal gastrin serum levels and stimulated serum gastrin levels after an hyperproteic meal, in a group of 20 healthy volunteers, with neither actual nor previous digestive symptoms. 60% were males, with a mean age of 35, 7 years, the highest percentage (40%) belonging to the fourth decade of life. The procedure used to determine serum gastrin levels is described. The mean value of the 3 samples obtained in basal conditions was of 51.01 pg/ml. The mean value of the 6 samples obtained after the stimulation meal was of 73.4 pg/ml. The results obtained in this study are discussed and compared with the ones of the reviewed literature.

Adolescent↗