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Steroid hormone measurement, first developed with radioimmunoassay, is now becoming easier with the use of automated platforms of immunoassay. However, some hormones remain uneasily detectable because of their low blood concentration, their structural homology or the presence of interferences. Liquid chromatography-tandem mass spectrometry (LC-MS/MS) can be considered as an alternative to immunoassays. This approach allows the simultaneous determination of several parameters thanks to its selectivity led by the detector mass spectrometer and the separate dimension of chromatography liquid. In addition, recourse to UHPLC (ultra high performance liquid chromatography) allows improving selectivity and sensitivity while limiting the samples volumes. The "ready-to-use" kits are now available and added to the "homemade" techniques developed by laboratories, thus giving opportunity for measurement of a wide steroid panel with only one sample. Finally, mass spectrometry methods, including a prior extraction step, allow the use of varied biological fluids (blood, urine, saliva…). Also, several clinical indications could gain from mass spectrometry, especially when hormone levels are low, when several steroids have to be identified, when the sample volume is low. However, this technology represents an important financial investment and in-depth staff training. In addition, some steroids are not easily quantifiable by mass spectrometry. It is likely by immunoassay and mass spectrometry, well-matched technologies, that we could answer the best to clinical questions about steroids.

This report describes the results of a multicentric study of biological methods for luteinizing hormone (hLH). The production of testosterone by animal Leydig cells is used by five laboratories with different methodologies including rat, mouse and pig cells. Dose-response curves of testosterone production, quality criteria and results on a physiological population of men and women, are reported and discussed. It is concluded that the bioactive determination of hLH must be considered as a reference method used in discordances between clinic and immunological methods.

Progressive supranuclear palsy (PSP) may sometimes be misdiagnosed as Parkinson's disease in its early stages, hence an early positive diagnosis of PSP based on dopamine D2 receptor density could be extremely valuable. In the present case report, the absence of dopamine D2 receptors was clearly demonstrated in the striatum using 123I-iodobenzamide (IBZM) tomoscintigraphy. This illustrates the potential use of IBZM tomoscintigraphy to identify Parkinson-like's disease presenting with decreased dopamine D2 receptor density; and hence to predict L-Dopa effectiveness. Further studies are needed to evaluate the vaue of IBZM tomoscintigraphy in the different Parkinson's like diseases.

The discrepancy between results obtained using different anti-hLH antibodies available on the market led us (in the context of a contract with the CNAMTS) to compare the results of hLH immunoassays (eight different reagents) with those of hLH bioassays based on the measurement of the steroidal activity of this hormone on mouse, rat or pig testicular preparations (five methodologies). Twenty-nine samples of serum or human serum pools were tested. The values resulting from these tests reveal differences linked to the nature of the antibodies or to the methodological conditions used for the testicular preparations. Some antibodies seem unable to identify some hLH forms which, however, can be detected by biological methods.

Unlabelled: The aim of the study was to compare plasmatic levels of calcitonin obtained after intradermic (ID) and usual subcutaneous (SC) route of administration., Method: 6 volunteers between 18 and 40 years old received calcitonin 0.5 mg (Cibacalcin, Ciba-Geigy Laboratory) by ID and SC routes in a random order but at the same site of injection. Each administration was spaced by 8 days. Plasmatic levels were measured by R.I.A. before administration then 2 (M2), 7 (M7), 15 (M15), 30 (M30) minutes and 1 (H1), 2 (H2), 4 (H4), 8 (H8), 12 (H12) hours after each administration., Results: Tmax were at 23.6 +/- 10 min and 16.2 +/- 7.5 min for SC and ID routes respectively. With ID route, Tmax was reached simultaneously or earlier (3 times). Cmax is significantly higher with ID route. Neither mean plasmatic levels at each plasmatic dosage nor mean areas under the curve between 0 to 1,440 min or between 0 to 480 min (this latest AUC calculate to minimize the importance of calcitonin basal level) were significantly different with ID and SC routes. 16 mild side effects (8 with each administration) were observed in 4 subjects. They appeared before 5 min. and were transient (1 hour) for cutaneous manifestations, and later between hours 3 and 7 for nausea and vomiting or asthenia. The mean lowering of calcemia was 0.29 +/- 0.21 and 0.18 +/- 0.11 mmol/l respectively for SC and ID route. In this study ID and SC routes for calcitonin administration are not different with regard to plasma levels and side effects.

The dermis, considered as a potential route of administration for drugs, has been widely and empirically used for more than a century. The comparative intravenous and intradermal administration of radiotracers makes it possible to demonstrate that the intradermal route has its own diffusion kinetics and its own biodistribution.

Two cases of sympathetic paraganglioma are reported: one, benign, in a 20-years old woman with arterial hypertension and attacks of excessive sweating; the other, malignant and with bone metastases, in a 44-years old woman. Both were diagnosed by scintigraphy, using meta-iodobenzylguanidine as radionuclide. This new radiopharmaceutic agent has recently been introduced for the detection of phaeochromocytomas, but it seems to be a general tissue marker of catecholamine uptake and storage. Its use as a therapeutic compound may also be envisaged.

In order to evaluate the frequency of elevated circulating calcitonin in patients with bone metastasis plasma calcitonin level was measured in 32 patients with breast carcinoma with and without bone metastasis. Calcitonin was found in normal ranges in all patients without metastasis. In patients with bone metastasis, 4 had normal level, 2 were found with elevated calcitonin. Our results suggest that elevated calcitonin is related to the presence of bone metastasis but is not a constant finding in these patients.

Investigation of cellular localization of hCG and alpha- and beta- subunits in 17 transitional cell carcinomas of urinary bladder was performed using immunohistochemical techniques. Serial sections were tested with monoclonal antibodies to hCG, free beta hCG and free alpha hCG. Transitional cell carcinomas producing hCG and/or beta hCG are easily found (6/17 cases). None of these tumors correspond morphologically to a choriocarcinoma. However, it must be mentioned that neoplastic areas exhibit some features reminiscent of a choriocarcinomatous structure. Notably, positive cells can be disposed at the periphery of neoplastic nests, mimicking the arrangement of syncytiotrophoblast. Positive neoplastic cells express hCG and/or beta hCG; alpha hCG immuno-reactivity is quite rare. The relative distribution of hCG/beta hCG is excessively variable from case to case. In contrast, normal transitional epithelium contains endocrine cells which only express the alpha-subunit of hCG.

The authors describe an immunoassay technique of serum progesterone using a chemiluminescent tracer (LIA): progesterone aminobutylethylisoluminol 11-a-hemisuccinate (P-ABEI). The intrinsic characteristics of this technique were studied. The progesterone concentrations of 62 serum samples were simultaneously titrated using this LIA technique and a RIA technique. This LIA technique is quite practicable. The intra and inter-series ability to reproduce this test, and the sensitivities are excellent and comparable to those obtained with RIAs. There is a good correlation between the serum concentrations of progesterone determined by LIA and RIA (y = 1.12 x + 3.2; r = 0.95). A test with paired series did not demonstrate any significant difference (t = 0.67; 0.1 less than p less than or equal to 0.375). In conclusion, with a few technical adjustments (automated light meter, "coat tube"), this method could be perfectly suitable for titrations in a Biology laboratory.

Based on experience of the last decade including 18 patients, the imaging procedures of medullary thyroïd carcinoma are reviewed. Ultrasonography of the neck is the most contributive for the locoregional expertise, in the preoperative period. All of the classical imaging procedures are useful in looking for the metastasis: namely bone scintiscan, liver ultrasonography, computerized tomography of the mediastinum. Associated parathyroid adenoma and pheochromocytoma are visualized respectively by technetium thallium subtraction scan and meta-iodobenzylguanidine scintigraphy. In the near future, immunoscintigraphy of calcitonin secreting tumors will be developed.

This report describes the comparison between two adrenal medulla imaging agents, mIBG and I-CPP. Biodistribution demonstrated an early and preferential uptake by both adrenal glands and heart and then storage in the adrenal gland of both agents, however I-CPP is less stable in vivo than mIBG. Reserpine depletion study in rat indicated that the I-CPP and mIBG uptake mechanisms are not similar.