Additional value of integrated 18F-choline PET/4D contrast-enhanced CT in the localization of hyperfunctioning parathyroid glands and correlation with molecular profile.

PURPOSE: The localization of hyperfunctioning parathyroid gland(s) (HPTG) in patients with primary hyperparathyroidism (PHPT) with negative or inconclusive first-line imaging is a significant challenge. This study aimed to evaluate the role of integrated 18F-choline PET/4D contrast-enhanced computed tomography (4DCeCT) in these patients, compare its detection rate and sensitivity with those of 18F-choline PET/CT and (4DCeCT), and analyse the association between choline metabolism and morphological, biochemical and molecular parameters of HPTG. METHODS: We prospectively enrolled 44 PHPT patients with negative or inconclusive first-line imaging. 18F-Choline PET/CT and 4DCeCT were performed at the same time, and integrated 18F-choline PET/4DCeCT images were obtained after coregistration. Experienced physicians examined the images. The SUVratio and degree of contrast enhancement were recorded for each positive finding. Histopathology, laboratory and multidisciplinary follow-up were used as the standard of reference. Both the detection rates and sensitivities of the three imaging modalities were calculated retrospectively. Immunohistochemistry was performed to evaluate the molecular profile of HPTGs. RESULTS: 18F-Choline PET/4DCeCT was positive in 32 of 44 patients with PHPT (detection rate 72.7%), and 31 of 31 surgically treated patients (sensitivity 100%). These results were significantly (p < 0.05) better than those of 18F-choline PET/CT (56.8% and 80%, respectively) and those of 4DCeCT (54.5 and 74%, respectively). A significant correlation between SUV and calcium level was found. In a multivariate analysis, only calcium level was significantly associated with 18F-choline PET/4DCeCT findings. SUVratio and Ki67 expression were significantly correlated. CONCLUSION: Integrated 18F-choline PET/4DCeCT should be considered as an effective tool to detect PHPT in patients with negative or inconclusive first-line imaging. Choline metabolism is correlated with both calcium level and Ki67 expression in HPTG.

Uncommon association of germline mutations of RET proto-oncogene and CDKN2A gene.

INTRODUCTION: Calcitonin measurement is advised in the diagnosis of thyroid nodules, as it is an accurate marker of medullary thyroid carcinoma (MTC). C-cell hyperplasia (CCH)-induced hypercalcitoninemia cannot be distinguished from that induced by MTC, unless surgery is performed. CASE: We report the clinical and biological features of a patient with a family history of cancer, including melanoma and pancreatic cancer, who had previously undergone surgery for melanoma. He presented the unusual association of papillary thyroid carcinoma (PTC), normocalcemic hyperparathyroidism, and hypercalcitoninemia with a pathological response to pentagastrin, which was histologically deemed secondary to CCH. Multiple endocrine neoplasia (MEN) 2A was diagnosed. RET gene analysis showed a p.V804M missense mutation in exon 14, a low- but variably penetrant defect found in both sporadic and MEN2A-associated MTC/CCH, and a p.G691S polymorphism in exon 11. Furthermore, the germline P48T mutation was found in the CDKN2A gene exon 1, which is known to be associated with melanoma and pancreatic cancer. The patient showed the uncommon coexistence of a germline mutation in two suppressor genes, RET and CDKN2A; this finding, deemed to be a mere coincidence, did not modify the phenotype expected by each single mutation. CCH associated with V804M RET mutation is a precancerous condition and surgery is recommended. In order to exclude MTC, surgery is advised in patients with a pathological calcitonin response to pentagastrin, in the absence of thyroid autoimmunity. CCH-induced hypercalcitoninemia can be associated with thyroid cancers other than MTC (e.g., PTC). Family history is important in scheduling specific genetic screening in high-risk patients and their relatives.

Hypopituitarism in the elderly: multifaceted clinical and biochemical presentation.

UNLABELLED: Hypopituitarism (HYPO) is a rare and under-investigated pathology in the elderly. AIM: to review our case records of patients > or =65 yrs with first diagnosis of anterior global hypopituitarism, in order to evaluate presentation symptoms, etiology, biochemical and hormonal pictures, pituitary morphology, and efficacy of therapy. PATIENTS: 15 patients (65-82 yrs) were studied: in 11 (73%) HYPO was secondary to pituitary macroadenoma (non-secreting in 10 and GH-secreting in 1); in 3 it was associated to empty sella, and in 1 to pituitary hypoplasia. RESULTS: major presenting symptoms were visual-field defects and asthenia (40%) but also memory and/or gait impairment and nausea (30%) and depression (20%) were significantly observed. Dyslipidemia (73%), anemia (20%) and severe hyponatremia (13%) were found. After starting substitutive therapy and clinical improvement, 10 patients with macroadenoma underwent uneventful neurosurgery, which improved visual alterations but not pituitary function. Immunohistochemistry showed positivity for FSH in one patient and for GH in one patient. Six out of the eight patients with a post-surgical tumor remnant required treatment (surgery/radiotherapy/somatostatin analogue treatment in the acromegalic patient). CONCLUSIONS: The diagnosis of HYPO is often delayed in the elderly, since symptoms may be ascribed to aging and associated comorbidities. In our series, most of the aspecific symptoms were retrospectively addressed to HYPO since their resolution/improvement with replacement therapy. The prevalent cause of HYPO remains non-functioning pituitary macroadenomas. Hyponatremia can be a life-threatening presenting symptom. Symptoms considered apparently aspecific in the elderly should be investigated in order to possibly diagnose an important treatable disorder as HYPO.

TSH-secreting adenomas: rare pituitary tumors with multifaceted clinical and biological features.

TSH-secreting pituitary adenomas (TSH-omas) are a rare cause of hyperthyroidism in clinical practice. As their diagnosis is often delayed, these tumors are mostly diagnosed as macroadenomas, preventing an effective and radical cure and leading to serious local and systemic comorbidities. In addition to neurosurgery, medical therapy with the effective and tolerable SS analogs is a fundamental tool for the treatment of TSHomas. We report 3 cases of TSH-macroadenomas which displayed different clinical presentations. All patients showed increased free-thyroid hormone levels with inappropriately normal (2 patients) or high (1 patient) TSH levels. Magnetic resonance imaging (MRI)/computed tomography (CT) evidenced a pituitary macroadenoma and octreoscan was positive in all patients. In the 2 patients who underwent neurosurgery, hormonal hypersecretion by the tumor normalized. Histology showed nuclear pleomorphism and fibrosis, whereas immunohistochemistry showed positivity for TSH and, in a lesser amount, for FSH. In one of these patient (case 1), however, the presence of a tumor remnant inside the left cavernous sinus prompted us, in accordance with the patient, to start therapy with octreotide- long-acting release. As the third patient had a cardiac comorbidity which contraindicated neurosurgery, he underwent satisfactory treatment with long-acting SS analogs alone which normalized thyroid hormone levels. In this case, previous treatment with amiodarone confused and delayed the correct diagnosis of TSH-oma. As a result of improved laboratory and morphological techniques, TSH-omas should currently be diagnosed in early stages, thus enabling most patients to be managed satisfactorily through a combined approach.

Primary "empty sella" in adults: endocrine findings.

Increasing evidence of impaired pituitary function in many subjects with primary empty sella (PES) has been reported. We conducted a retrospective analysis of our patients with PES, in order to ascertain presenting symptoms and endocrine status on diagnosis and during follow-up. Magnetic resonance imaging (MRI) of the pituitary leading to the diagnosis of PES was performed in 8 patients (5 F and 3 M, age: 60.1 +/- 3.3 years, M +/- SE; group 1) after the diagnosis of global anterior hypopituitarism (H), and in 20 patients (F, age 56.9 +/- 2.2 years, group 2) for other clinical reasons. Baseline determinations of pituitary and target gland hormones and of IGF-I were performed. GH response to GHRH plus arginine stimulation was also evaluated. Ten age- and BMI-matched subjects (7 F, 3 M, age: 53.0 +/- 4.0 years) with normal pituitary function served as controls (C). In group 1, the presenting symptoms leading to the diagnosis of H were consciousness disturbances, hyponatremia and chronic fatigue. The GH response to stimulation was absent (peak:1.0 +/- 0.3 ng/ml) and IGF-I levels (60.1 +/- 9.3 ng/ml) were significantly lower (p<0.001) than in C and group 2 PES patients. Among group 2 PES patients, the main presenting symptoms were headache and visual alterations. Baseline hormone levels proved normal in 17 subjects, while slight hyperprolactinemia was observed in 2 and hypogonadotropic hypogonadism in one. The GH response to stimulation (12.9 +/- 3.4 ng/ml) and IGF-I levels (141.7 +/- 12.0 ng/ml) were lower (p<0.05) than in C (GH: 33.4 +/- 8.8 ng/ml, IGF-I: 193.1 +/- 20.3 ng/ml). PES is a heterogeneous condition that ranges from hypopituitarism to various degrees of isolated GH deficiency, and which needs careful endocrine assessment, treatment and follow-up.

Effects of alpha-interferon on insulin-like growth factor-I, insulin-like growth factor-II and insulin-like growth factor binding protein-3 secretion by a human lung cancer cell line in vitro.

The aim of our study was to evaluate the effect of alpha-interferon (alpha-IFN) on cell growth and on the different IGF system components in a human non-small cell lung cancer line (Calu-6) in vitro. Our results confirm the release of IGF-I and IGF-II by these cells. The amount of IGF-II in conditioned media (10.25 +/- 3.95 nM/10(6) cells, mean +/- SE) was more than 10-fold higher than that of IGF-I. alpha-IFN treatment reduced IGF-II levels in the media, with a maximal effect between 1 and 10 U/ml (delta% of control: -31 and -55%, respectively, p < 0.05). IGF-I was significantly reduced at 0.5 U/ml (p < 0.01). No difference, however, was observed in IGF mRNA expression between untreated and alpha-IFN treated cells. An increase in IGF-I and IGF-II intracellular levels in alpha-IFN treated cultures was observed, suggesting that alpha-IFN can regulate the transfer of these peptides into the cells. Furthermore, IGF type-I and particularly type-lI receptor expression was increased after alpha-IFN treatment. IGFBP-3 was detected only in trace amounts in the conditioned media; however, it showed an increase after alpha-IFN treatment (+110% at 1 U/ml). IGFBP-3 mRNA expression showed a slight increase after treatment with 1 and 10 U/ml. alpha-IFN (1-10 U/ml) reduced the stimulatory effect of IGF-I on cell replication (p < 0.01), inhibited (p < 0.01) cell replication in untreated and in fetal calf serum (FCS)-stimulated cells, and increased apoptosis in Calu-6 cells. Our data suggest that alpha-IFN may exert its effects at the cellular level in part through modification of the local IGF system.

[Effect of long-term treatment with octreotide-lar in a TSH-secreting pituitary macroadenoma and secondary hyperthyroidism]. / Effetto del trattamento a lungo termine con octreotide-Lar in un caso di macroadenoma ipofisario TSH-secernente.

A 74 year-old man was admitted to the hospital for heart failure and atrial fibrillation episodes. He had been irregularly treated for hyperthyroidism during the previous 3 years, with poor control. Thyroid function evaluation showed secondary hyperthyroidism, with high free thyroid hormone levels and TSH inappropriately in the high-normal range (4.2 mU/ml), only slightly responsive to TRH-stimulation (6 microU/ml). Alpha-subunits were hyper-responsive to TRH stimulation (+123%). Thyroid autoimmunity tests were negative and ultrasonography evidenced a diffusely enlarged gland. Magnetic resonance (MR) imaging of the pituitary showed a macroadenoma. The patient underwent transphenoidal adenomectomy, and immunohistochemistry confirmed the diagnosis of a TSH-secreting pituitary macroadenoma. A moderate secondary hyperthyroidism was still present and a new MR evidenced residual disease, involving the right cavernous sinus. A (111)In-octreoscan revealed an increased captation in this area. The patient was treated with octreotide-Lar (20 mg/monthly), which normalized FT3, FT4 and TSH levels already after 3 months of therapy. This effect is still maintained at 42 months of treatment. MR imaging showed a reduction in the residual lesion after 18 months (>50% in comparison with postsurgical MR) and a further decrease after 36 months of treatment). This suggests that the antiproliferative effect on the adenomatous cells is progressive and continues over time. This patients did not receive radiotherapy, so this action is entirely due to the medical treatment. No significant side effects developed and the patient's compliance was good. He has not had further arrhythmic episodes.

Leydig cell tumour-induced bilateral gynaecomastia in a young man: endocrine abnormalities.

Among the various causes of gynaecomastia, testicular malignancies are an uncommon, life-threatening condition, which require prompt treatment. The case of a 26-year-old healthy man is described, who reported a 6-month painful bilateral gynaecomastia associated with secondary hypogonadism. Normal circulating 17beta-oestradiol (E2) levels showed an enhanced response to human chorionic gonadotrophin (hCG) testing, which led to a reduced testosterone (T)/E2 ratio. Both clinical and hormonal findings normalized following surgical exeresis of a left testicular mass, which proved to be a Leydig cell tumour (LCT) at histology. This report underlines the importance of ultrasonographic evaluation of the testes, whenever breast enlargement occurs in a healthy man, despite unremarkable findings on testicular examination. In addition, our case demonstrates that normal unstimulated circulating E2 levels do not allow the presence of a stromal testicular tumour to be ruled out and that the response of restored T levels to hCG testing can remain blunted up to 1 year after surgery. Finally, we claim that T/E2 ratio may be a useful tool in evaluating derangement of the endocrine milieu secondary to LCT.

[Severe postmenopausal hyperandrogenism due to an ovarian lipoid cell tumor: a case report]. / Descrizione di un caso clinico di severo iper-androgenismo postmenopausale dovuto a un tumore ovarico a cellule lipidiche.

The case of a 62-year-old woman with severe post-menopausal hirsutism is described. Her clinical history revealed regular menstrual periods until menopause at the age of 50, hysterectomy for fibromatosis at 58 years, non-insulin dependent diabetes mellitus, hypertension, obesity, severe hirsutism, which had developed in the previous 3 years, with a deeping of the voice. Examination showed android obesity, hypertension and severe hirsutism involving the face and the trunk. Endocrine evaluation pointed out regular adrenal function, serum total and free-testosterone in the adult male range, with normal androstenedione, DHEAS and 17OHP levels. Estradiol was slightly increased and LH and FSH were inappropriately low for her post-menopausal age. Computed tomography of the abdomen showed regular adrenal glands, and a radio-labeled cholesterol scan was negative. A further pelvic transvaginal ultrasonography revealed a small cystic formation near the right ovary and a slight increase in the size of the left ovary. The patient underwent bilateral ovariectomy. Histological examination showed a lipoid cell tumor within the left ovary. Immunohistochemical studies were positive for inhibin and cytokeratin. After surgery, serum testosterone fell to normal levels, gonadotropins increased to menopausal levels, confirming that the tumor was able to produce both LH, and FSH-inhibiting factors, and hirsutism greatly improved. Periodic hormonal tests remained normal and CT of the abdomen and pelvic ultrasonography did not show alterations at a 3 years follow-up.

Use of an artificial neural network to predict Graves' disease outcome within 2 years of drug withdrawal.

BACKGROUND: Graves' disease (GD) is an autoimmune disorder characterized by hyperthyroidism, which can relapse in many patients after antithyroid drug treatment withdrawal. Several studies have been performed to predict the clinical course of GD in patients treated with antithyroid drugs, without conclusive results. The aim of this study was to define a set of easily achievable variables able to predict, as early as possible, the clinical outcome of GD after antithyroid therapy. METHODS: We studied 71 patients with GD treated with methimazole for 18 months: 27 of them achieved stable remission for at least 2 years after methimazole therapy withdrawal, whereas 44 patients relapsed. We used for the first time a perceptron-like artificial neural network (ANN) approach to predict remission or relapse after methimazole withdrawal. Twenty-seven variables obtained at diagnosis or during treatment were considered. RESULTS: Among different combinations, we identified an optimal set of seven variables available at the time of diagnosis, whose combination was useful to efficiently predict the outcome of the disease following therapy withdrawal in approximately 80% of cases. This set consists of the following variables: heart rate, presence of thyroid bruits, psycological symptoms requiring psychotropic drugs, serum TGAb and fT4 levels at presentation, thyroid-ultrasonography findings and cigarette smoking. CONCLUSIONS: This study reveals that perceptron-like ANN is potentially a useful approach for GD-management in choosing the most appropriate therapy schedule at the time of diagnosis.

[Genotypic sex and phenotypic sex: clinical, biochemical and molecular aspects in a patient with male hypogonadism and 46XX-45XO karyotype]. / Sesso genotipico e sesso fenotipico: aspetti clinici, biochimici e molecolari in un paziente con ipogonadismo maschile e cariotipo 46XX-45X0.

We report here the case of a patient with primary male ipogonadism, with small testes and deficient virilization of the external genitalia, but with 46XX, 45X0 karyotype. Hormonal determinations showed high LH and FSH and low testosterone levels. Ultrasonography confirmed the presence of small testes within the scrotum. Cytogenetic analysis demonstrated a female karyotype, with 90% 46XX, 10% 45X0 mosaicism. Using DNA probes for genes located on the Y chromosome, the presence of the "Sex-Determining Region" of the Y chromosome (SRY) was evidenced in the genomic DNA of this patient. By Fluorescence in Situ Hybridization (FISH), SRY locus was localized in the p terminal region of an X chromosome. SRY is the primary inducer of testis development; it acts as a transcription factor leading to a sequence of gene activations critical in the process of testicular differentiation and morphogenesis. A condition characterized by testicular development in subjects who lack a normal Y chromosome has been described; most of these patients are carriers of the short arm of the Y chromosome transferred to one of the two X chromosome, suggesting a form of X-Y paternal interchange. In our patient, the development of male gonade in the absence of an Y chromosome was explained by the demonstration of the SRY gene in an X chromosome.

[Pituitary pathology in elderly patients admitted in a division of internal medicine. Description of 3 cases]. / Patologia ipofisaria in anziani ricoverati presso una Divisione di Medicina Interna. Descrizione di tre casi.

Pituitary diseases are often unrecognized in the elderly, although if they can be at the basis of several pathological conditions. We report three clinical cases. Patient n. 1: 87 years old woman, in poor general condition. Thyroid function evaluation showed secondary hypothyroidism. Subsequent pituitary function evaluation demonstrated hypopituitarism with empty sella. The diagnosis was "hypopituitarism with secondary hypothyroidism and adrenocortical insufficiency, in empty sella" starting substitutive treatment with glucocorticoids and L-thyroxine, with improvement in her clinical conditions. Patient n. 2: 74 years old woman, with severe congestive heart failure. Her clinical history revealed hypothyroidism. An endocrine evaluation (in absence of therapy) demonstrated panhypopituitarism with secondary hypothyroidism and adrenocortical insufficiency in presence of empty sella. The patients was started on substitutive treatment and her conditions improved. Patient n. 3: 74 years old man with several atrial fibrillation episodes and hyperthyroidism. Thyroid function evaluation suggested secondary hyperthyroidism confirmed by the presence of a pituitary macroadenoma. The patient underwent surgical adenomectomy by trans-sphenoidal route. The clinical conditions of the patient improved, but a slight secondary hyperthyroidism was still present caused by the persistence of residual pathological tissue in the right cavernous sinus region confirmed by octreoscan suggesting the presence of a lesion endowed with somatostatin receptors. The patient was started on long acting octreotide treatment, which is still in progress. In conclusion, pituitary diseases pass often unrecognized in the elderly. Their prompt recognition and treatment can resolve dangerous situations for the patients.

Detection of serum immunoglobulin M to human cytomegalovirus by western blotting correlates better with virological data than detection by conventional enzyme immunoassay.

Western blotting (immunoblotting) with proteins separated from purified human cytomegalovirus (HCMV) particles (viral WB) has repeatedly been shown to be a reliable and sensitive method for detecting HCMV-specific immunoglobulin M (IgM). The aim of the present work was to determine whether IgM detected by viral WB correlates with virological diagnosis better than conventional enzyme immunoassay (conv-EIA). The presence of an active HCMV infection was documented on the basis of isolation of virus from urine and/or saliva and on the basis of antigenemia and/or PCR with polymorphonuclear leukocytes for immunocompetent and immunocompromised subjects, respectively. The agreement observed between IgM detected by viral WB and the results obtained by virological detection of HCMV was significantly higher (88.7%) than the agreement of IgM detected by conv-EIA and virological results (67.5%).

Intrafollicular insulin-like growth factor-II levels in normally ovulating women and in patients with polycystic ovary syndrome.

OBJECTIVE: To investigate intrafollicular insulin-like growth factor II (IGF-II) in patients affected with polycystic ovary syndrome (PCOS) in comparison with normal women. DESIGN: Insulin-like growth factor-II was determined in 103 follicular fluids (FF) from normally ovulating women and in 102 FF from patients with PCOS. Ribonucleic acid was extracted from granulosa cells of follicles obtained from control and PCOS patients and from tissue from polycystic ovaries. SETTING: Procedures were performed in a university laboratory. PATIENTS: Twenty-nine normally ovulating women and 19 patients with PCOS underwent ovulation induction for IVF-ET with LH-releasing hormone (LH-RH) analog and gonadotropins. Eleven of them, 4 to 8 months later, underwent ovulation induction with approximately the same dosage of gonadotropins plus a standard dosage of GH. MAIN OUTCOME MEASURES: Intrafollicular IGF-II, IGF-I, epidermal growth factor (EGF), transforming growth factor beta 2, (TGF-beta 2), inhibin, and steroids were evaluated by appropriate RIA, immunoenzymatic assay (EIA), and ELISA assays. The expression of the gene encoding IGF-II was analyzed by Northern blot. RESULTS: Intrafollicular IGF-II was lower in PCOS than in controls. Accordingly, IGF-II messenger RNA expression was lower in PCO than in normal granulosa cells. Several differences in FF IGF-I, EGF, inhibin, and TGF-beta 2 concentrations were observed between PCOS and controls. CONCLUSIONS: Both IGF-II and IGF-I were reduced in PCOS, confirming a possible role of an IGF imbalance in the development of this disease.

The impact of obesity on hormonal parameters in hirsute and nonhirsute women.

The influence of obesity on sex hormone-binding globulin (SHBG) and androgen concentrations in hirsute and nonhirsute women has been evaluated. The study was performed in 226 hirsute women (88 obese and 138 non-obese) classified as being affected by polycystic ovarian syndrome (PCOS) or by idiopathic hirsutism (IH) and in 100 nonhirsute control women ([C] 60 lean and 40 obese). SHBG, free testosterone (fT), androstenedione (A), estradiol (E2), dehydroepiandrosterone sulfate (DHEAS), and gonadotropin levels were measured during the first week of the menstrual cycle by radioimmunoassay (RIA). A significant negative correlation between SHBG and body mass index (BMI) was observed in PCOS, IH, and C women. In obese women--whether PCOS, IH, or C-fT levels were significantly higher and, conversely, SHBG levels were lower than in non-obese women. A negative correlation between SHBG and fT was evidenced in each group. Upper-body obesity was associated with lower SHBG and higher fT levels than lower-body obesity. In conclusion, obesity, particularly upper-body obesity, is associated with a reduction in SHBG and an increase in fT in both nonhirsute and hirsute women.

Increased 17 alpha-hydroxyprogesterone response to ACTH in silent adrenal adenoma: cause or effect?

OBJECTIVE: Recent studies suggest a possible connection between silent adrenal nodules and mild forms of 21-hydroxylase deficiency. It remains unclear whether the enzymatic deficiency is generalized or intrinsic to the adrenal mass. To help to clarify this, we have studied 17 alpha-OH-progesterone (17OH-P) response to ACTH stimulation in a group of patients with adrenal 'incidentaloma' in comparison with normal subjects. In patients who underwent surgical treatment, the test was repeated to evaluate possible modifications in 17OH-P behaviour after resection of the adrenal mass. SUBJECTS AND METHODS: Fifteen subjects with incidentally discovered asymptomatic adrenal masses were studied. Basal hormone evaluations were normal, with normal cortisol suppression after low-dose dexamethasone. Iodocholesterol scanning, performed in 12 patients, showed normal bilateral adrenal uptake in 2 subjects and an increased uptake on the side of the lesion in 10 subjects. In every patient, ACTH stimulation was performed to evaluate the secretory response of cortisol, 17OH-P, progesterone and dehydroepiandrosterone sulphate. An identical test was performed in 10 control subjects with normal adrenal glands, matched for age and sex. In six patients with an adrenal lesion > 3.5 cm, the ACTH stimulation test was repeated one month after surgery. RESULTS: The 17OH-P response to ACTH stimulation was significantly higher in subjects with adrenal 'incidentaloma' than in controls (P < 0.01). In particular, 10 subjects out of 15 (66%) evidenced a 17OH-P peak > 18 nmol/l at 60 minutes. No differences were seen in baseline 17OH-P or cortisol levels or in cortisol response to ACTH between the two groups. Dehydroepiandrosterone sulphate concentrations were significantly lower in patients with adrenal 'incidentaloma' than in normals. In six patients who had an increased 17OH-P response to ACTH on initial evaluation, the ACTH test was repeated one month after surgery. In five of these patients, 17OH-P response to ACTH was clearly reduced, suggesting that in these cases the enzymatic defect was restricted to the adenoma. In the other patient, however, stimulated 17OH-P levels remained unchanged. In this case, therefore, all of the adrenal tissue seems to be involved, suggesting a late-onset 21-hydroxylase deficiency. No significant modifications in cortisol response to ACTH were observed. CONCLUSION: It seems therefore that in some cases of incidentaloma the steroidogenic enzymatic defect may be secondary to the adenomatous proliferation, while in others such defects may induce the development of silent adrenal nodules.