17. Utility of Metabolic Imaging in Oral Squamous Cell Carcinoma (SCC) Staging. Experience in 30 Patients

Purpose: SCC represents nearly 90% of all oral malignancies, with an increasing incidence. Accurate Tumour-Node-Metastasis staging (TNM) is mandatory for planning surgical options and chemotherapy-radiotherapy management. Positron Emission Tomography (PET) using 18F-Fluorodeoxyglucose (FDG) provides functional information about tumoral tissues that may improve preoperative staging obtained by conventional morphologic procedures (CT-MRI). The purpose of this study is to evaluate the accuracy of FDG-PET in oral SCC staging and to compare those data from conventional and PET studies according to the pathologic results obtained from surgical specimen.Methods: A prospective study of 30 patients was carried out, through a 26 months period. Inclusion criteria include positive biopsy for Oral SCC, no other malignancies during the past 5 year and surgery as preferred therapeutic option. All patients underwent CT, MRI, and FDG-PET studies consecutively. Results obtained from conventional and PET preoperative staging were compared with those from postoperative histopathological studiesResults: FDG-PET modified preoperative staging obtained by conventional morphologic studies in 21% cases, which was confirmed postoperatively by histological findings. Kappa test showed higher values for PET studies (0.89) than conventional studies (0.41), when compared with postoperative controlConclusion: FDG-PET may be helpful to improve the accuracy of conventional studies in oral SCC preoperative TNM staging, although no definitive conclusions can be withdrawn due to the limited size of the sample. Modifications of preoperative staging showed by PET are a matter of controversy and must be kept in mind for further studies.

Serum levels of eosinophil cationic protein and eosinophil protein x in pollen atopic patients with stable asthma and its relation with bronchial hyperresponsiveness

Eosinophils are important effector cells in allergic inflammation described in allergic rhinitis (AR) and allergic bronchial asthma (BA). During the pollen season serum levels of eosinophil cationic protein (ECP) and eosinophil X protein/eosinophil-derived neurotoxin (EPX/EDN) are increased in BA. The aim of the present study was to evaluate the serum levels of ECP and EPC in pollen atopic patients with AR and BA during the winter. 92 patients were studied. They were divided into three groups: I 29 patients with AR, II 51 patients with BA and III 12 healthy subjects. Allergic rhinitis and bronchial asthma were diagnosed by routine clinical tests: clinical history, skin tests, total IgE and specific IgE. In addition ECP and EPX were determined in serum. All patients were asymptomatic, stable and without medical treatment. Methacholine challenge test (MCT) was performed in all patients. MCT were positive in 4 patients of group I and 45 patients of group II. ECP levels (ug/l) were: 21 (I), 24 (II) and 7 (III). EPX levels (ug/l) were 35 (I), 45 (II) and 21 (III). Statistical differences (p < 0.01) were observed both in ECP and EPX levels in patients with MCT positive in relation to patients with MCT negative, and in allergic patients (I and II) in comparison with the healthy subjects (III) (p < 0.01). ECP and EPX serum levels are increased in patients with a positive MCT in the winter, out of the pollen season, when patients are asymptomatic, stable and without treatment. This fact suggests that eosinophils play an important role in the pathogenesis of bronchial asthma.

[PET-FDG in thyroid cancer with high thyroglobulin levels and negative 131-I scan. A case report]

The value of whole body PET-FDG in the evaluation of metastases has been demonstrated in a wide variety of tumors. In this report, we present the case of a patient with antecedent of papillary thyroid carcinoma, who was operated twelve years ago, and submitted to an ablative dose of residual thyroid tissue through 131I, being the levels of thyroglobulin normals. After twelve years of evolution, the patient refers bag pain and respiratory trouble, appearing in the CT image suspicious of metastases in right pulmonary base. The levels of thyroglobulin were shown increased, being the 131I scan negative. A whole body PET-FDG study was performed in order to exclude metastases of his malignant process, showed multiple high FDG uptake focus in brain, cerebellum, neck, chest, lymphatic nodes and bone, suggestive of dedifferentiated disease These findings were confirmed subsequently in the clinic evolution. Therefore, whole-body PET-FDG is a complementary diagnostic technique for study patients with CDT (Thyroid Differentiated Carcinoma) with 131I scan negative and rising thyroglobulin levels.

[PSA and PSAD study in patients with renal dysfunction]

This study analyzes the changes in serum and urinary PSA values in 28 subjects; 13 with creatinine clearance under 75 ml/mn and 15 with creatinine clearance over 75 ml/mn. Both groups were compared for prostate size, measured by transrectal ultrasound, prostate weight, serum PSA (SPSA), 24h urine PSA (PSAO), PSA clearance (PSACl), serum creatinine (SCr), creatinine clearance (CrCl), PSA density (PSAD), PSA/creatinine ratio (PSA/Cr) and PSACl/CrCl ratio. Mean values of SPSA and PSAO were 4.5 +/- 0.8 and 222 +/- 29.7 ng/ml respectively, values for SCr, CrCl and PSACl averaging 1.62 +/- 0.2 mgr/dl, 71.6 +/- 6.5 ml/mn and 150.5 +/) 32.9 ml/mn. Median prostate size was 32.6 +/- 3.9 cc, with weights of 40.3 +/- 4.9 g and mean PSA density (PSAD) 0.13 +/- 0.02. The results of the homogeneity study showed that there are no significant differences between both groups with regard to the variables considered in the study. SPSA values were higher in patients with CrCl < 75; 3.4 vs 5.7, but not significantly. There are no significant differences between PSAO and PSACl values for both groups, even though PSAO levels were higher in patients with CrCl < 75 ml/min (p = 0.1). PSAD values for patients with CrCl > 75 ml/mn were lower than those for patients with CrCl < 75 ml/mn; 0.09 vs 0.17 (p = 0.08). In the entire sample, PSAD levels showed correlation with SPSA and PSA/Cr values; R = 0.63 (P = 0.0003) and r = 0.5 (p = 0.009) respectively. Also, they were significantly but inversely correlated with PSACl levels; r = - 0.5 (p = 0.006) and PSACl/CrCl; r = - 0.048 (p = 0.01). No correlation was seen between PSAD values and the following parameters; PSAO (p = 0.7), SCr (p = 0.5) and CrCl (p = 0.27). When the group of patients with CrCl < 75 ml/mn is considered, PSAD values are correlated exclusively with PSACl values; r = - 0.69 (p = 0.008) and PSACl/CrCl; r = 0.68 (p = 0.009). Our data appear to indicate that there is a certain relationship between PSAD and the renal function although the physiopathological mechanism responsible for that is unknown. Nevertheless, considering the sample size, more comprehensive studies will be necessary to obtain more convincing results.