Marine Ollivier, Magalie Haissaguerre, Amandine Ferriere and Antoine Tabarin
Julie Brossaud, Philippe Gosse, Blandine Gatta, Antoine Tabarin, Guy Simonnet and Jean-Benoît Corcuff
We set up plasma normetanephrine (pNMA) and metanephrine (pMA) assays as they demonstrated their usefulness for diagnosing phaeochromocytomas. Our scope is to describe some practical laboratory aspects and the clinical relevance of these assays in our endocrinological or cardiological departments.
We retrospectively reviewed the results of MA from a population of in- and outpatients over a 7-year period. Subjects (n=2536) from endocrinological or cardiological departments were investigated (66 phaeochromocytomas). Urinary NMA (uNMA) and pNMA, and urinary MA (uMA) and pMA were assayed by HPLC with electrochemical detection.
pNMA and pMA assays are now more frequently requested than uNMA and uMA. This changed our laboratory work load with improved delivery, sensitivity and reliability of plasma assays as well as reduced apparatus maintenance time.
The pNMA and pMA upper reference limits (URLs) of subjects with no phaeochromocytoma were 1040 and 430 pmol/l respectively. Sensitivity and specificity based on receiver operating characteristic curves optimal points were 83 and 93% for pNMA at 972 pmol/l and 67 and 98% for pMA at 638 pmol/l. Sensitivity and specificity of paired tests of pMA (positive test: at least one analyte above its URLs) were 100 and 91% respectively.
The very low concentration of analytes requires a sustained very good apparatus analytical sensitivity. This can be obtained in an up-to-date laboratory. In terms of clinical performances, assays in plasma or urine are equivalent. Depending on local preferences, populations, strategies or departments, requests for one or the other assay may sustain the need for specifically defined reference ranges.
Antoine Tabarin, Pierre Cassiède, Anne Perrot Minot, Jean Claude Cuber, Patrick Roger and Dominique Ducassou
The nature of NPY-like immunoreactivity (NPY-LI) was investigated in plasma and tumour tissue of 1 7 pheochromocytoma patients by HPLC, gel filtration and isoelectric focusing using two radioimmunoassays (RIAs) directed against the C- and N-terminals of NPY respectively. The two RIAs gave similar results in pheochromocytomas: 86% of cases had higher NPY-LI concentrations than those found in normal adrenal glands and NPY-LI behaved like authentic human NPY during gel filtration and HPLC. Assessed by isoelectric focusing, NPY was found to be amidated in seven of nine tumours. Contrary to the findings obtained in tumours, the results of the two RIAs in plasma samples were not always concordant: compared to controls, elevated concentrations of NPY-LI were found in 86% of cases of pheochromocytomas using the C-terminally directed RIA and in 76% of cases using the N-terminally directed RIA. The results of HPLC and gel filtration of NPY-LI in plasma suggested that circulating Cand N-terminal NPY fragments account for the discrepancy between the results of the two RIAs. In conclusion, most pheochromocytomas contain large amounts of NPY-LI that behaved like authentic NPY by chromatographic analysis. On the contrary, circulating NPY-LI in some pheochromocytoma patients is heterogeneous with cleaved products which influence differently the power of the C- and N-terminally directed RIAs for the diagnosis of pheochromocytoma.
Cédric Fagour, Stéphane Bardet, Vincent Rohmer, Yannick Arimone, Pierre Lecomte, Nathalie Valli and Antoine Tabarin
Prognostic factors for progression of benign adrenocortical adenomas (AI) remain poorly known. We assessed the usefulness of 131I-6-β-iodomethylnorcholesterol scintigraphy (IMS) to predict the occurrence of adrenal hyperfunction or mass enlargement.
Fifty-one consecutive inpatients with unilateral AI and normal 24-h urinary free cortisol (UFC) were enrolled in a multicenter observational prospective study to investigate the relationship between the scintigraphic pattern and the progression of biological abnormalities of the hypothalamo-pituitary–adrenal axis or tumor size.
Biochemically defined ‘subclinical’ Cushing's syndrome (SCS) was found at baseline in 47% of patients. Unilateral uptake (UU) was significantly associated with SCS (P<0.05). During the follow-up (4.3±1.6-year): 53% of patients showed unchanged hormonal evaluation, 29% displayed intermittent SCS and 18% showed definitive hormonal progression of SCS but without overt biochemical hypercortisolism. UU was associated with persistence of SCS and hormonal progression (P<0.01). In multivariate analysis, UU and impaired 1 mg dexamethasone suppression were independently associated with hormonal progression. Three patients with UU developed clinical CS despite persistently normal UFC. Tumor size increased in 10% patients and was not associated with any scintigraphic pattern.
Evolution of SCS toward overt biochemical CS in patients with AI is a rare event during a 4-year follow-up. UU is predictive for the occurrence of SCS, its persistence and progression within the spectrum of SCS. Further studies aiming to establish the clinical consequences of SCS are needed to recommend IMS as a complementary evaluation in patients with AI and biochemical SCS.
Jean-Benoît Corcuff, Jacques Young, Pauline Masquefa-Giraud, Philippe Chanson, Eric Baudin and Antoine Tabarin
Severe Cushing's syndrome elicited by ectopic ACTH syndrome (EAS) or adrenal carcinoma (ACC) can threaten life in the short term. The effectiveness of oral administration of the inhibitors of steroidogenesis ketoconazole and metyrapone in this situation is poorly described.
To report the short-term effectiveness and tolerability of metyrapone and ketoconazole elicited either by EAS or by ACC in patients exhibiting severe hypercortisolism.
Retrospective analysis of data obtained for patients with urinary free cortisol (UFC) level estimated to be fivefold the upper limit of the normal range (ULN).
Patients and settings
A total of 14 patients with EAS and eight with ACC treated in two tertiary-care university hospitals.
Metyrapone and ketoconazole treatment in combination (along with symptomatic treatments for co-morbidities).
Evolution of clinically relevant endpoints (blood pressure, kalaemia and glycaemia) and biological intensity of hypercortisolism 1 week and 1 month after starting steroidogenesis inhibition.
After 1 week of treatment, median UFC fell from 40.0 to 3.2 ULN and from 16.0 to 1.0 ULN in patients with EAS and ACC respectively. Median UFC after 1 month of treatment was 0.5 and 1.0 ULN in patients with EAS and ACC respectively and UFC values were normal in 73 and 86% of patients respectively. Clinical status improved dramatically along with kalaemia, glycaemia and blood pressure, allowing a decrease in the relevant treatments.
Side effects were minimal and only two patients (one EAS and one ACC) experienced plasma transaminase elevations necessitating ketoconazole withdrawal.
Metyrapone–ketoconazole combination therapy is well tolerated and provides rapid control of endocrine cancer-related life-threatening hypercortisolism.
Antoine Tabarin, Jean-Benoît Corcuff, Michel Rashedi, Reine Angibeau, Jean-Marie Caille, Dominique Ducassou, Bernard Dufy and Patrick Roger
A multihormonal response to CRH during inferior petrosal sinus sampling in patients with Cushing's disease has recently been described. Whether it reflects multihormonal secretion by the corticotropic adenoma, or secretion by non-tumorous adjacent cells via paracrine mechanisms remains debatable. We have compared the effect of CRH on ACTH, GH, PRL and TSH secretion during inferior petrosal sinus sampling with its effect on the in vitro secretion of the corticotropic adenoma after excision in one case of Cushing's disease. Before CRH injection in vivo results show significant central-peripheral gradients for all hormones but only ACTH lateralized to the side of the tumor. After CRH administration, the petrosal concentrations of all hormones increased preferentially on the side of the adenoma resulting in significant intersinus gradients: 8.1 for ACTH, 2.0 for GH, 1.8 for PRL and 1.5 for TSH. In vitro results: the adenoma cells were immunostainable for ACTH only. In culture, they secreted ACTH only. Addition of CRH to the culture induced a mean increase of 160% in ACTH secretion but GH, PRL and TSH remained undetectable. Our results favor the hypothesis that the multihormonal response to CRH seen during inferior petrosal sinus sampling in Cushing's disease reflects a paracrine stimulation of the adjacent non-tumorous pituitary cells by the corticotropic adenoma.
Jacques Young, Magalie Haissaguerre, Oceana Viera-Pinto, Olivier Chabre, Eric Baudin and Antoine Tabarin
Ectopic ACTH syndrome (EAS) is rare but is frequently a severe condition because of the intensity of the hypercortisolism that may be dissociated from the tumoral condition. EAS should often be considered as an endocrine emergency requiring an emergency response both in terms of diagnostic procedures and therapeutic interventions. Patient management is complex and necessitates dual skills, in the diagnosis and treatment of CS and in the specific management of neuroendocrine tumors (NET). Therefore, initial management should be performed ideally by experienced endocrinology teams in collaboration with specialized hormonal laboratory, modern imaging platforms and intensive care units. Diagnostic procedures vary according to the endocrine and tumoral contexts but should be reduced to a minimum in intense hypercortisolism. Preventive and curative treatments of cortisol-induced comorbidities, non-specific management of hypercortisolism and etiological treatments should be considered simultaneously. Therapeutic strategies vary according to (1.) the intensity of hypercortisolism, the general condition of the patient and associated comorbidities and (2.) the tumoral status, ranging from resectable ACTH secreting tumors to non-resectable metastatic endocrine tumors or occult tumors. The ideal treatment is complete excision of the ACTH-secreting tumor that can be performed rapidly or after preoperative preparation using cortisol-lowering drugs. When this is not possible, the therapeutic strategy should be discussed by a multidisciplinary experienced team in a personalized perspective and include variable combinations of pharmacological agents, bilateral adrenalectomy and non-specific tumoral interventions. Here we discuss the diagnosis and therapeutic strategies including the modern, currently available tools and emphasize on the operational effectiveness of care.
Sophie Mauclère-Denost, Sophie Leboulleux, Isabelle Borget, Angelo Paci, Jacques Young, Abir Al Ghuzlan, Desiree Deandreis, Laurence Drouard, Antoine Tabarin, Philippe Chanson, Martin Schlumberger and Eric Baudin
The benefit-to-risk ratio of a high-dose strategy at the initiation of mitotane treatment of adrenocortical carcinoma (ACC) remains unknown.
To evaluate the performance of a high-dose strategy, defined as the highest tolerated dose administered within 2 weeks and maintenance therapy over 4 weeks, we conducted a single-center, prospective study with two main objectives: to evaluate the percentage of patients who achieve a plasma mitotane level above 14 mg/l and to evaluate the tolerance of mitotane within the first 3 months of treatment. Plasma mitotane levels were measured monthly using HPLC.
Twenty-two patients with ACC were prospectively enrolled. The high-dose mitotane strategy (4 g/day or more in all patients, with a median of 6 g/day within 2 weeks) enabled to reach the therapeutic threshold of >14 mg/l at 1, 2, or 3 months in 6/22 patients (27%), 7/22 patients (32%), and 7/22 patients (32%) respectively. In total, a therapeutic plasma mitotane level was reached in 14 out of 22 patients (63.6%) during the first 3 months in ten patients, and after 3 months in four patients. Grade 3–4 neurological or hematological toxicities were observed in three patients (13.6%).
Employing a high-dose strategy at the time of mitotane initiation enabled therapeutic plasma levels of mitotane to be reached within 1 month in 27% of the total group of patients. If this strategy is adopted, we suggest that mitotane dose is readjusted according to plasma mitotane levels at 1 or/and 2 months and patient tolerance.
Martin Fassnacht, Wiebke Arlt, Irina Bancos, Henning Dralle, John Newell-Price, Anju Sahdev, Antoine Tabarin, Massimo Terzolo, Stylianos Tsagarakis and Olaf M Dekkers
By definition, an adrenal incidentaloma is an asymptomatic adrenal mass detected on imaging not performed for suspected adrenal disease. In most cases, adrenal incidentalomas are nonfunctioning adrenocortical adenomas, but may also represent conditions requiring therapeutic intervention (e.g. adrenocortical carcinoma, pheochromocytoma, hormone-producing adenoma or metastasis). The purpose of this guideline is to provide clinicians with best possible evidence-based recommendations for clinical management of patients with adrenal incidentalomas based on the GRADE (Grading of Recommendations Assessment, Development and Evaluation) system. We predefined four main clinical questions crucial for the management of adrenal incidentaloma patients, addressing these four with systematic literature searches: (A) How to assess risk of malignancy?; (B) How to define and manage low-level autonomous cortisol secretion, formerly called ‘subclinical’ Cushing’s syndrome?; (C) Who should have surgical treatment and how should it be performed?; (D) What follow-up is indicated if the adrenal incidentaloma is not surgically removed?
(i) At the time of initial detection of an adrenal mass establishing whether the mass is benign or malignant is an important aim to avoid cumbersome and expensive follow-up imaging in those with benign disease. (ii) To exclude cortisol excess, a 1mg overnight dexamethasone suppression test should be performed (applying a cut-off value of serum cortisol ≤50nmol/L (1.8µg/dL)). (iii) For patients without clinical signs of overt Cushing’s syndrome but serum cortisol levels post 1mg dexamethasone >138nmol/L (>5µg/dL), we propose the term ‘autonomous cortisol secretion’. (iv) All patients with ‘(possible) autonomous cortisol’ secretion should be screened for hypertension and type 2 diabetes mellitus, to ensure these are appropriately treated. (v) Surgical treatment should be considered in an individualized approach in patients with ‘autonomous cortisol secretion’ who also have comorbidities that are potentially related to cortisol excess. (vi) In principle, the appropriateness of surgical intervention should be guided by the likelihood of malignancy, the presence and degree of hormone excess, age, general health and patient preference. (vii) Surgery is not usually indicated in patients with an asymptomatic, nonfunctioning unilateral adrenal mass and obvious benign features on imaging studies. We provide guidance on which surgical approach should be considered for adrenal masses with radiological findings suspicious of malignancy. Furthermore, we offer recommendations for the follow-up of patients with adrenal incidentaloma who do not undergo adrenal surgery, for those with bilateral incidentalomas, for patients with extra-adrenal malignancy and adrenal masses and for young and elderly patients with adrenal incidentalomas