[CME: Paraneoplastic Endocrine Syndromes]

CME: Paraneoplastic Endocrine Syndromes Abstract. Paraneoplastic endocrine syndromes are caused by ectopic hormone production by malignant tumor cells. Knowledge of paraneoplastic endocrine syndromes may allow a timely diagnosis of the underlying cancer at a treatable stage and, on the other hand, appropriate treatment of the endocrine manifestations reduces morbidity and mortality of the affected patients. The most common endocrine syndromes are paraneoplastic hypercalcaemia, caused by the secretion of PTHrP, and hyponatremia, caused by the inadequate secretion of ADH. Although there may be clinical symptoms like fatigue, nausea/vomiting and renal insufficiency for hypercalcaemia and gait disturbances and mental alterations for hyponatremia, the diagnosis must be confirmed by laboratory testing and prompt the search for associated tumors.

Paraneoplastic Galactorrhea in Childhood T-ALL: An Evaluation of Tumor-derived Prolactin

T-cell acute lymphoblastic leukemia (T-ALL) comprises 15% of childhood leukemia. Although multiagent pulse chemotherapy has improved event-free survival in recent decades, the lack of reliable prognosticators and high rate of relapse remain a challenge. Described is a novel discovery of tumor-derived hyperprolactinemia in childhood T-ALL through a case associated with paraneoplastic galactorrhea. Prolactin production by tumor cells, although a rare phenomenon, is previously demonstrated in several adult cancers and 2 pediatric malignancies with unknown implications. This is the first report demonstrating tumor-derived prolactin in pediatric T-ALL and offers potential as a disease marker and therapeutic drug target.

Hypoglycemia Observed on Continuous Glucose Monitoring Associated With IGF-2-Producing Solitary Fibrous Tumor

CONTEXT

Tumors producing IGF-2 (IGF-2oma) are a major cause of spontaneous hypoglycemia. The treatment mainstay is surgical resection. Many case reports note resolution of hypoglycemia after IGF-2oma resection; however, outcomes are variable according to tumor type. We report a case of resolving hypoglycemia, observed on continuous glucose monitoring, after resection of an IGF-2-producing solitary fibrous tumor of pleura and review the current literature.

CASE REPORT

A 69-year-old woman presented with impaired consciousness because of hypoglycemia. An IGF-2oma was diagnosed as the cause for hypoglycemia because of decreased serum insulin and IGF-1, the presence of a pleural tumor, and a high-molecular-weight form of serum IGF-2 detected by Western immunoblot. Surgical resection was performed; pathological examination demonstrated a solitary fibrous tumor with low-grade malignancy. Continuous glucose monitoring showed reversal of hypoglycemia after tumor resection. Approximately 2 years after resection, the patient has no signs of tumor recurrence or hypoglycemia.

CONCLUSIONS

An IGF-2-producing solitary fibrous tumor of pleura in this case caused hypoglycemia. From a search of the literature of 2004-2014, 32 cases of IGF-2oma with hypoglycemia that underwent radical surgery were identified; in 19 (59%) patients, hypoglycemia was reversed, and there was no subsequent recurrence. The remaining 13 (41%) patients experienced tumor recurrence or metastasis an average of 43 months after initial tumor resection. The tumor of the present case was a low-grade malignancy. Regular follow-up with biomarker monitoring of glucose metabolism and assessment of hypoglycemic symptomatology, in conjunction with imaging tests, is important for detecting possible tumor recurrence and metastasis.

No metabolic impact of surgical normalization of hyperandrogenism in postmenopausal women with ovarian androgen-secreting tumours

AIM

To examine the impact of surgical normalization of testosterone on body weight and on glucose and lipid metabolism and insulin sensitivity in a group of hyperandrogenic women with ovarian androgen-secreting tumours (OAST).

METHODS

Five consecutive postmenopausal hyperandrogenic patients (aged 63 ± 5 years) with a diagnosis of OAST were prospectively evaluated. Clinical signs, symptoms and metabolic and hormonal parameters were collected at the time of the diagnosis and at follow-up, 12 months after surgical oophorectomy. A group of 15 age-matched and body mass index-matched postmenopausal control women served as a reference group.

RESULTS

At baseline, patients with OAST had very high testosterone levels and inappropriately low gonadotrophin levels for their menopausal status. All the women were overweight or obese, and one had a history of polycystic ovary syndrome and Type 2 diabetes. Twelve months after surgical oophorectomy, testosterone and gonadotrophin levels returned to appropriate values for menopausal status in all patients; however, no change in body weight was found. Fasting glucose levels slightly increased (P < 0·05) without any significant change in other metabolic parameters. In the woman with diabetes, a moderate decrease in haemoglobin A1c occurred. Red blood cell count and haematocrit values were normalized (P < 0·05, respectively).

CONCLUSION

Normalization of androgen levels achieved after surgical oophorectomy did not cause any significant change in body weight and insulin sensitivity. These findings may offer a different perspective on the impact of hyperandrogenaemia on metabolism.

[Ectopic hormonal syndrome]

Ectopic hormonal syndrome, the most common cause of paraneoplastic syndrome, is due to an inappropriate secretion of peptide hormones by neoplasms derived from non-endocrine tissue, often discovered even by an occult neoplasm. The diagnosis of ectopic hormonal syndrome is established based on the following criteria;1. abnormal clinical signs and symptoms and/or inappropriate hormonal secretion associated with tumors;2. the abnormal endocrine syndrome and hormone secretion are reversed by tumor resection, and relapsed after tumor recurrence; 3. an arteriovenous gradient for the hormone across the tumor; and 4. the hormone can be detected in the tumor tissue. The treatment of choice for ectopic hormonal syndrome is directed at the primary tumor by surgical resection, radiotherapy, or chemotherapy, and the palliative treatment to control excess hormone secretion is effective in alleviation of symptoms.

Mediastinal lymph node metastasis of lung cancer with an unknown primary lesion having concurrent endocrine abnormality and acanthosis nigricans: report of a case

We herein describe a patient we encountered in whom mediastinal lymph node metastasis of lung cancer with an unknown primary lesion was complicated by both an endocrine abnormality and acanthosis nigricans. A 66-year-old male visited a local hospital and was diagnosed as having acanthosis nigricans. The patient was referred to our hospital for further examination. Computed tomography scans of the chest and the abdomen showed no adverse findings except for an enlargement of the mediastinal lymph node. No malignant lesions were detected in examinations of the upper gastrointestinal tract. Based on the above findings, the lesion was thus considered to possibly be mediastinal lymph node metastasis of an unknown primary tumor or malignant lymphoma. A thoracoscopic biopsy of the mediastinal lymph node was performed. The patient was diagnosed to have mediastinal lymph node metastasis of lung cancer with an unknown primary lesion and endocrine abnormality resulting from paraneoplastic syndrome. Palliative radiation therapy was initiated to prevent superior vena cava syndrome and esophageal passage failure or dysphagia. The cutaneous lesions markedly improved thereafter. The serum levels of adrenocorticotropic hormone decreased.

The Current Role of Venous Sampling in the Localization of Endocrine Disease

Endocrine venous sampling plays a specific role in the diagnosis of endocrine disorders. In this article, we cover inferior petrosal sinus sampling, selective parathyroid venous sampling, hepatic venous sampling with arterial stimulation, adrenal venous sampling, and ovarian venous sampling. We review their indications and the scientific evidence justifying these indications in the diagnosis and management of Cushing's syndrome, hyperparathyroidism, pancreatic endocrine tumors, Conn's syndrome, primary hyperaldosteronism, pheochromocytomas, and androgen-secreting ovarian tumors. For each sampling technique, we compare its diagnostic accuracy with that of other imaging techniques and, where possible, look at how it impacts patient management. Finally, we incorporate venous sampling into diagnostic algorithms used at our institution.

Parathyroid-hormone-related-protein-associated hypercalcemia in a patient with CLL-type low-grade leukemic B-cell lymphoma

Humoral hypercalcemia of malignancy is a common metabolic disturbance associated with solid tumors, but it also occurs in lymphoma patients. Among these, low grade B-cell lymphoma accounts for only few cases, in which secretion of parathyroid hormone-related protein (PTHrP) remains even exceptional. We report the very rare case of a patient with a CLL type low grade leukemic B-cell lymphoma showing PTHrP-related hypercalcemia without evidence of bone lesions. Using immunohistochemistry, we demonstrate the cytoplasmic expression of PTHrP by the lymphoma cells in the bone marrow obtained at the onset of hypercalcemia. We postulate a pathogenetic role of leukemic cell production and secretion of PTHrP in hypercalcemia in low grade leukemic B-cell lymphoma.

Neuroendocrine tumors secreting growth hormone-releasing hormone: Pathophysiological and clinical aspects

Hypothalamic GHRH is secreted into the portal system, binds to specific surface receptors of the somatotroph cell and elicits intracellular signals that modulate pituitary GH synthesis and/or secretion. Moreover, GHRH is synthesized and expressed in multiple extrapituitary tissues. Excessive peripheral production of GHRH by a tumor source would therefore be expected to cause somatotroph cell hyperstimulation, increased GH secretion and eventually pituitary acromegaly. Immunoreactive GHRH is present in several tumors, including carcinoid tumors, pancreatic cell tumors, small cell lung cancers, endometrial tumors, adrenal adenomas, and pheochromocytomas which have been reported to secrete GHRH. Acromegaly in these patients, however, is uncommon. The distinction of pituitary vs. extrapituitary acromegaly is extremely important in planning effective management. Regardless of the cause, GH and IGF-1 are invariably elevated and GH levels fail to suppress (<1 microg/l) after an oral glucose load in all forms of acromegaly. Dynamic pituitary tests are not helpful in distinguishing acromegalic patients with pituitary tumors from those harbouring extrapituitary tumors. Plasma GHRH levels are usually elevated in patients with peripheral GHRH-secreting tumors, and are normal or low in patients with pituitary acromegaly. Unique and unexpected clinical features in an acromegalic patient, including respiratory wheezing or dyspnea, facial flushing, peptic ulcers, or renal stones sometimes are helpful in alerting the physician to diagnosing non pituitary endocrine tumors. If no facility to measure plasma GHRH is available, and in the absence of MRI evidence of pituitary adenoma, a CT scan of the thorax and abdominal ultrasound could be performed to exclude with good approximation the possibility of an ectopic GHRH syndrome. Surgical resection of the tumor secreting ectopic GHRH should be the logical approach to a patient with ectopic GHRH syndrome. Standard chemotherapy directed at GHRH-producing carcinoid tumors is generally unsuccessful in controlling the activated GH axis. Somatostatin analogs provide an effective option for medical management of carcinoid patients, especially those with recurrent disease. In fact, long-acting somatostatin analogs may be able to control not only the ectopic hormonal secretion syndrome, but also, in some instances, tumor growth. Therefore, although cytotoxic chemotherapy, pituitary surgery, or irradiation still remain available therapeutic options, long-acting somatostatin analogs are now preferred as a second-line therapy in patients with carcinoid tumors and ectopic GHRH-syndrome.

[Hypogonadism despite of normal testosterone levels]

We report on a 19 year old patient with clinical signs of hypogonadism (small testicles, missing pollutions and diminished beard growth) despite of normal testosterone levels. Further diagnostic procedures revealed panhypopituitarism with insufficiency of the gonadotrope, somatotrope and corticotrope axis due to a beta-HCG-producing suprasellar germinoma with intracerebral metastases. Paraneoplastic production of beta-HCG resulted in sufficient stimulation of Leydig cells with normal production of testosterone, which had partly masked clinical symptoms of gonatrope insufficiency. The patient was treated by combined radiochemotherapy and is in remission since 7 years.

EPO-producing gastric carcinoma in a hemodialysis patient

A case of erythrocytosis caused by gastric cancer that produced erythropoietin is described. To the authors' knowledge, no case of erythropoietin-producing gastric cancer has been reported until now. A 73-year-old man with a 4-year history of maintenance hemodialysis for diabetic nephropathy required phlebotomy. Serum erythropoietin level was 181 mU/mL (181 IU/L). Gastroscopy results showed rough mucosa with hemorrhaging caused by gastric cancer. The patient underwent distal gastrectomy, and serum erythropoietin level decreased to 27.1 mU/mL (27.1 IU/L) by postoperative day 8. Existence of erythropoietin in the tumor tissue was confirmed immunohistochemically. The presence of severe acquired cystic disease of the kidney, renal cell carcinoma, and other malignant tumors should be investigated in hemodialysis patients displaying erythrocytosis.

Growth hormone-secreting pituitary adenomas in childhood and adolescence: features and results of transnasal surgery

OBJECTIVE

Pituitary tumors causing gigantism are rare in childhood and adolescence. In a review of 2367 patients with pituitary adenomas who were treated between 1970 and 1997, we found 15 cases (0.63%, 9 male and 6 female patients) of growth hormone-secreting pituitary adenomas in patients who were less than 20 years of age at the time of surgery, and we compared their characteristics with those of adenomas in an adult group.

METHODS

Patients were grouped according to their ages at the first operation, with five patients (33.3%) in the prepubescent group (0-11 yr), eight (53.3%) in the pubescent group (12-17 yr), and two (13.3%) in the postpubescent group (18-19 yr). All 15 patients exhibited the typical symptoms of growth hormone oversecretion. The incidence of hyperprolactinemia among patients with prepubescent onset was 66.7%. Radiological examinations demonstrated microadenomas in 4 patients (26.7%) and macroadenomas in 11 patients (73.3%). The mean follow-up period was 73.5 months.

RESULTS

Direct transnasal explorations were performed for all patients. Tumor invasion into the cavernous sinus was observed in six patients (40%). Radical tumor resection was performed for four patients (80%) in the prepubescent group, for five patients (62.5%) in the pubescent group, and for neither patient in the postpubescent group. Surgical morbidity was caused by permanent diabetes insipidus in three patients (20%). Rapid growth was postoperatively improved in 80% of the prepubescent age group. The recurrence rate was 13.3% (2 of 15 patients).

CONCLUSION

Transnasal pituitary surgery was found to be as safe in pediatric patients with gigantism as in adults. Growth hormone-secreting pituitary adenomas in childhood and adolescence were more likely to be invasive or aggressive than were those in adulthood. The clinical biological characteristics for children were different from those for adults.

Serum levels of carboxyterminal cross-linked telopeptide of type I collagen (ICTP) in the differential diagnosis of the syndromes of inappropriate secretion of TSH

BACKGROUND AND OBJECTIVE

Serum TSH assay is a very sensitive and specific index of thyroid hormone (TH) action. Nevertheless, in particular clinical situations, such as those of inappropriate TSH secretion, the measurement of additional parameters evaluating peripheral TH action may be required in order to achieve a correct diagnosis and to assess the impact that thyroid hormone have on a given tissue. The availability of a specific RIA for serum carboxy-terminal cross-linked telopeptide of type I collagen (ICTP) prompted us to study the usefulness of this specific marker of bone resorption in the differential diagnosis of thyroid disorders.

DESIGN

Serum ICTP levels were measured in: (a) 10 patients with TSH-secreting pituitary adenoma (TSH-oma), (b) 40 with thyroid hormone resistance (RTH), as well as in (c) 28 patients with Graves' disease or toxic nodular goitre, (d) 31 with autoimmune primary hypothyroidism (PH) and in 8 of them during L-T4 replacement therapy, (e) 23 with central hypothyroidism (CH) during L-T4 therapy and 2 months after its withdrawal, and (f) 26 during TSH-suppressive treatment for goitre or non-metastatic differentiated thyroid cancer. Results were compared with those obtained in 2 groups of normal controls (Group A, n = 61, age range: 23-68 years; Group B, n = 32, age range: 6-15 years).

METHODS

Serum TSH, free T4 (FT4) and free T3 (FT3) were measured by immunofluorometric assays. Serum ICTP was measured by a specific RIA with a sensitivity of 0.5 +/- 0.1 microgram/l, and intra- and interassay coefficients of variation lower than 6%.

RESULTS

Mean values of serum ICTP levels in adult controls were 3.8 +/- 1.6 (+/-SD) microgram/l, while in pre- or peri-pubertal controls it was higher than in adults (14.4 +/- 3.1 micrograms/l). Patients with TSH-oma showed significantly increased ICTP levels (8.7 +/- 5.0 micrograms/l, P < 0.001 vs controls), in contrast to those with RTH (3.0 +/- 1.0 micrograms/l, P < 0.02 vs controls). In the differential diagnosis of inappropriate secretion of TSH, ICTP values above 5 micrograms/l strongly indicated the presence of a TSH-oma. Circulating ICTP concentrations were definitely high in thyrotoxic patients (9.4 +/- 4.7 micrograms/l, P < 0.001) and values overlapping the normal range were observed in 8 cases, thus giving to this test a sensitivity and specificity of 71% and 93%, respectively. In contrast, serum ICTP levels in both PH and CH untreated patients were in the normal range, although significantly lower than in controls (2.6 +/- 1.0 and 1.8 +/- 0.7 micrograms/l, P < 0.001). During replacement therapy, ICTP levels rose significantly in both hypothyroid groups (5.1 +/- 2.5 and 2.7 +/- 1.3 micrograms/l). In 2 CH patients, borderline high ICTP levels (7.0 and 7.1 micrograms/l), associated with FT3 concentrations in the upper limit of the normal range, suggested the presence of L-T4 overtreatment; L-T4 dose reduction was followed by the decrease of both indices in a more physiological range (ICTP: 4.2 and 4.7 micrograms/l; FT3: 8.5 and 6.0 pmol/l). In patients treated with TSH-suppressive therapy at the minimal effective dose, ICTP levels did not significantly differ from those observed in adult controls (4.3 +/- 2.0 micrograms/l). The overall correlations between serum ICTP and FT4 or FT3 levels were highly significant (P < 0.001).

CONCLUSIONS

The present data indicate that serum type I collagen (ICTP) concentrations are modulated by circulating thyroid hormone concentrations. ICTP measurement is particularly useful in the differential diagnosis of the syndromes of inappropriate TSH secretion, in estimating thyroid hormone impact on bone in primary hyperthyroid states, and its longitudinal evaluation may reveal L-T4 overtreatment in patients on substitutive or TSH-suppressive therapy.

Masculinizing and feminizing syndromes caused by functioning tumors

Steroidogenic tumors are derived from cells of male and female reproductive tracts, adrenal glands, central nervous system, and, to a lesser degree, from the liver and pituitary gland. The symptoms caused by these tumors are related to their secretory products. Because enzymatic pathways are shared by both adrenal- and gonadal-derived tissues, and the conversion of some of these steroids occurs in the adipose tissue, positive identification of many lesions cannot be based on peripheral blood hormone levels alone, but require complex protocols to improve diagnostic accuracy. Furthermore, these tumors often are smaller than the size limit of conventional imaging modalities and thus demand more precise imaging techniques. Although diagnosis and localization may be challenging, the rewards of a positive prognosis, with complete reversal of symptoms, are more likely to occur with early detection and treatment. This article is a review of the clinical syndromes associated with pediatric steroidogenic tumors; suggested strategies to facilitate their diagnosis, localization, and treatment are provided.

[Laparoscopic adrenalectomy. Experiences with 50 patients]

Fifty patients with adrenal tumors (18 men and 32 women, average age 51.8 years) underwent laparoscopic adrenalectomy from February 1992 to October 1995. Clinical diagnosis included pheochromocytoma in 3 patients, primary aldosteronism (including 1 with a 11-OH-corticosterone-producing tumor) in 15, Cushing's syndrome (including 7 with pre-Cushing's syndrome) in 13, non-functioning tumors in 17, 1 metastatic adrenal carcinoma, and 1 adrenal tuberculosis. Transperitoneal laparoscopic adrenalectomy was performed by the method reported previously. Extraperitoneal laparoscopic adrenalectomy was performed with the patient under general anesthesia in the lateral position. A working space was created by inserting a balloon dissector through a small skin incision. A total of four trocars were inserted. Three of the 50 patients were switched to open surgery, including 1 with metastatic adrenal carcinoma and 1 with adrenal tuberculosis. Laparoscopic tumor removal was successful in the other 47 patients. The average operating time and blood loss were 209 min and 177 ml, respectively. Blood loss was greater in the patients with pheochromocytoma. In patients with Cushing's syndrome, postoperative recovery tended to take longer. Postoperative complications occurred in 40% of the patients in this group, but all complications were minor and successfully treated without any surgical procedures. In the 10 patients undergoing retroperitoneal laparoscopic adrenalectomy, operative courses were excellent, excluding 1 patient with adrenal tuberculosis. Although laparoscopic adrenalectomy is considered to be appropriate for patients with pheochromocytoma and Cushing's syndrome, it appears unsuitable for the removal of malignant and inflammatory lesions.

Normogonadotropic primary amenorrhea in a growth hormone-deficient woman with ectopic posterior pituitary: gonadotropin pulsatility and follicle-stimulating hormone bioactivity

We studied the gonadotropic function in a 25-year-old woman suffering from congenital GH deficiency, complaining of primary amenorrhea and wishing to become pregnant. She disclosed a hypoplasic anterior pituitary within a small sella turcica and an ectopic posterior pituitary lobe located below the median eminence. Immunoreactive LH and FSH plasma levels were normal, basal and in response to a GnRH iv bolus but estradiol was low. LH pulse frequency was elevated and FSH bioactivity was low in a granulosa cell aromatase bioassay. Pulsatile administration of iv GnRH at a slower, normal pace, failed to induce ovulation or to increase FSH bioactivity, with or without concomitant GH replacement. However treatment with exogenous im gonadotropins, when preceeded by GH replacement, succeeded in inducing mature oocytes and pregnancy. We concluded that the hypogonadism observed in this patient was due to rapid GnRH pulsatility and poor biological activity of endogenous FSH.

Magnetic resonance imaging measurements of pituitary stalk compression and deviation in patients with nonprolactin-secreting intrasellar and parasellar tumors: lack of correlation with serum prolactin levels

Prolactin (PRL) Levels are frequently elevated in patients with non-PRL-secreting adenomas or other intrasellar and parasellar diseases ("pseudoprolactinomas"). This phenomenon is believed to result from a loss of dopaminergic inhibition on pituitary lactotrophs and is known as the "stalk-section effect." Using magnetic resonance imaging scans and a high-magnification sella technique, we measured a number of parameters indicative of the disruption of normal sellar structures. The investigator was blind to the patient's diagnosis and PRL level while collecting the data. Parameters measured were the tumor size, the angular deviation of the pituitary stalk, and the degree of compression of the pituitary stalk. Measurements were obtained from 44 patients with pathologically confirmed tumors that had no immunohistochemical reactivity to PRL. PRL levels were often higher than expected. Four patients (9%) had a PRL level of more than 150 ng/ml, and three patients (7%) had a PRL level of 200 ng/ml or more. One patient with a plasmacytoma eroding the sella floor had a PRL level as high as 504 ng/ml. There was no significant correlation of PRL level and the degree of pituitary stalk compression, stalk deviation, or tumor size. PRL levels were found to be markedly elevated in some patients with a tumor causing little distortion of the pituitary stalk. Conversely, PRL levels were often normal despite evidence of massive distortion of the stalk. Therefore, magnetic resonance imaging evidence of pituitary stalk distortion cannot be used to determine the diagnosis of prolactinoma versus pseudoprolactinoma in most cases.(ABSTRACT TRUNCATED AT 250 WORDS)

Craniopharyngioma: endocrine abnormalities at presentation

Craniopharyngioma is the most common childhood tumor to involve the hypothalamus and pituitary. Although endocrine disturbances can be found in 80-90% of patients at presentation, only a minority of subjects seek medical attention for an endocrine-related complaint. Hormonal studies, while limited, indicate GH deficiency in 75% of children; deficiencies of LH/FSH (40%), ACTH (25%) and TSH (25%) also are common. In contrast, diabetes insipidus has been noted in only 9-17% of subjects prior to surgery. When possible, full evaluation of pituitary function should be performed; the minimum preoperative evaluation must include testing for and treatment of ACTH-adrenal insufficiency and diabetes insipidus.

Long-term follow-up results in hormonally active pituitary adenomas after primary successful transsphenoidal surgery

The long-term results of transsphenoidal surgery for hormonally active pituitary adenomas were assessed in 3 follow-up studies. Eight out of 50 patients with microprolactinomas developed a persisting postoperative re-increase of prolactin levels during an average follow-up period of 4.1 years. None of the 43 acromegalic patients who had achieved a suppression of growth hormone to below 2 ng/ml during an oral glucose load shortly after surgery relapsed. However, when the remission criterion was only based on basal growth hormone below 5 ng/ml 4 out of 61 patients showed a re-increase of growth hormone levels to persistently elevated values during an average follow-up period of 6.1 years. 14 out of 66 patients followed-up for an average of 8.2 years after successful primary microadenomectomy for Cushing's disease developed recurrent hypercortisolism as documented by an abnormal suppression of cortisol after oral low dose dexamethasone.

[HCG producing malignant teratoma of the testis: a rare cause of precocious isosexual maturation in boys]

Human chorionic gonadotropin (HCG) from a testicular tumor histologically diagnosed from its metastases to be a malignant teratoma induced elevated testosterone levels and subsequent precocious isosexual development in a 12-year-old boy. The endocrinologic consequences of long term ectopic HCG production in the prepubertal male are discussed. The case report illustrates the value of HCG serum levels as a marker for tumor activity.

Sex hormone-binding globulin measurement in patients with inappropriate secretion of thyrotropin (IST): evidence against selective pituitary thyroid hormone resistance in nonneoplastic IST

The differential diagnosis of the various forms of inappropriate secretion of TSH (IST), i.e. generalized thyroid hormone resistance (GRTH), selective pituitary resistance [non-neoplastic IST (nnIST)], and tumoral pituitary TSH hypersecretion [neoplastic IST (nIST)], mainly rests on clinical observation, skull imaging, and measurement of several parameters assessing peripheral thyroid hormone effects. Clinically, patients with GRTH usually display compensated hypothyroidism, while those with nnIST or nIST are hyperthyroid. Since sex hormone-binding globulin (SHBG) measurement has been shown to be a reliable parameter in distinguishing between euthyroid and hyperthyroid states, we evaluated serum SHBG levels in 39 patients with IST (7 with GRTH, 15 with nnIST, and 17 with nIST). The results were compared to those in 68 normal subjects, 76 hyperthyroid patients, and 31 hypothyroid patients. SHBG levels in patients with either GRTH or nnIST were similar to those in controls or hypothyroid patients [GRTH, 40.5 +/- 11.8 (+/- SD) nmol/L (range, 26.4-57.5); nnIST, 29.7 +/- 12.8 nmol/L (range, 6.8-46.8); controls, 36.7 +/- 21.7 nmol/L (range, 5.4-96.5); hypothyroid, 30.8 +/- 14.4 nmol/L (range, 10.4-63.3)]. On the contrary, SHBG levels in patients with either overt hyperthyroidism or nIST were significantly higher than those in the above groups [hyperthyroid, 149 +/- 111 nmol/L (range, 48-557); nIST, 99.5 +/- 54.7 nmol/L (range, 21.6-259)]. The apparent overlap of SHBG values between hyperthyroid patients and controls almost completely disappeared when comparisons were made with control groups matched for age and sex. Additional indices of peripheral thyroid hormone action (basal metabolic rate, cardiac systolic time intervals, and Achilles' reflex time) were normal in patients with GRTH, while they were in the hyperthyroid range in patients with nnIST and nIST. After successful treatment of hyperthyroidism, SHBG levels normalized in patients with nIST, but they did not change in patients with nnIST. In conclusion, the measurement of SHBG in patients with IST is useful in differentiating the neoplastic form from that due to thyroid hormone resistance, but it fails to distinguish between generalized and pituitary resistance to thyroid hormone action. Moreover, the present data suggest that the resistance to thyroid hormone action in patients with nnIST is not selective at the thyrotroph cell level, but also involves the hepatic SHBG-synthesizing cells, thus supporting the view that the various forms of thyroid hormone resistance could represent a continuum of the same defect with variable expression in different tissues.

Endocrine activity of the "silent" adrenocortical adenoma is uncovered by response to corticotropin-releasing hormone

The purpose of this study was to ascertain whether the pituitary-adrenal responses to human corticotropin-releasing hormone (hCRH) in "non-functioning" adrenocortical adenoma would uncover a functional activity in these adrenal nodules. Eleven patients with incidentally discovered "silent" adrenocortical adenoma and eleven controls were studied. The initial clinical and laboratory examination, including an overnight 1 mg dexamethasone suppression test, revealed no abnormalities in any of the subjects. IR-ACTH and serum steroids (F, S, P, 17OHP, 18OHB, and aldosterone) were normal in both controls and patients. After pulse IV injection of 100 micrograms hCRH, the cortisol response was significantly exaggerated (P = 0.01). Stimulated plasma ACTH levels were, however, significantly lower in patients than in controls (P = 0.01), indicating counter-feedback regulation of cortisol. The peak cortisol/peak ACTH ratio (Fmax/ACTHmax) in the patients was significantly elevated (26.8 +/- 4.37 nmol/ng vs. 14.6 +/- 2.16 nmol/ng, P = 0.02). Two further patients with incidentally discovered "pre-Cushing's" adrenocortical adenoma displayed an even higher ratio (43.5 and 45.5 nmol/ng). In established Cushing's syndrome due to an autonomous adrenocortical adenoma, suppression of ACTH and of the ACTH response to hCRH occurs with a very high basal cortisol/basal ACTH ratio. Our findings suggest some functional activity even in clinically "silent" adrenocortical adenoma. Response to hCRH uncovers a continuous spectrum between adrenocortical adenoma, "pre-Cushing's", and Cushing's syndrome.

Female pseudohermaphroditism due to a maternal adrenocortical tumor

A 15-yr-old, apparently male, patient presented with a 2-yr history of gynecomastia and poor genital development. A normally formed, but small, penis with a phallic urethra was present, and testes were impalpable. The karyotype was 46,XX, and at laparotomy a uterus, Fallopian tubes, and ovaries were found, but there was no testicular tissue. The mother had had regular periods ever since menarche at 14 yr. She had complained of hirsutism since the birth of the child, and on examination 15 yr later had marked clitoromegaly. Serum androgens were elevated: testosterone, 4.5 nmol/L (normal, 0.5-3); dehydroepiandrosterone sulfate, 18 mumol/L (normal, 3-12); and androstenedione, 35 nmol/L (normal, 3-8). All failed to suppress with dexamethasone. Abdominal computed tomographic scan revealed a 9 X 6-cm mass in the position of the left adrenal gland. This was removed at laparotomy and found to be an adrenocortical tumor. Postoperatively, the androgens returned to normal. Virilization of a female fetus due to androgens secreted by a maternal adrenal tumor has only been described three times previously, and the presentation has never been delayed so long.

Immunochemical characterization of circulating parathyroid hormone-related protein in patients with humoral hypercalcemia of cancer

Tumors from patients with humoral hypercalcemia of cancer produce a parathyroid hormone-related protein (PTHRP). We have developed two region-specific immunoassays capable of measuring PTHRP in plasma: an immunoradiometric assay directed toward PTHRP amino acid sequence 1 to 74 and a radioimmunoassay directed toward PTHRP amino acid sequence 109 to 138. Sixty normal subjects had low or undetectable plasma PTHRP (1 to 74) concentrations (mean, 1.9 pmol per liter) and undetectable PTHRP (109 to 138) concentrations (less than 2.0 pmol per liter). Patients with humoral hypercalcemia of cancer (n = 30) had elevated levels of both PTHRP (1 to 74) (mean, 20.9 pmol per liter) and PTHRP (109 to 138) (mean, 23.9 pmol per liter). The plasma concentrations of immunoreactive PTHRP correlated with the levels of urinary cyclic AMP excreted; in some patients, the concentrations decreased after the tumors were resected. Patients with chronic renal failure (n = 15) had plasma PTHRP (1 to 74) concentrations similar to those in the normal subjects, but their plasma PTHRP (109 to 138) concentrations were elevated (mean, 29.6 pmol per liter). The levels of both peptides were normal in patients with hyperparathyroidism and those with hypercalcemia due to various other causes. Breast milk contained high concentrations of PTHRP. An anti-PTHRP (1 to 36) immunoaffinity column failed to extract PTHRP (109 to 138) immunoactivity from plasma, suggesting that the C-terminal region circulates as a separate peptide. We conclude that plasma PTHRP concentrations are high in the majority of patients with cancer-associated hypercalcemia and that the circulating forms of PTHRP in such patients include both a large N-terminal (1 to 74) peptide and a C-terminal (109 to 138) peptide. Measuring the concentrations of PTHRPs may be useful in the differential diagnosis of hypercalcemia.

Testicular cancer secretes intact human choriogonadotropin (hCG) and its free beta-subunit: evidence that hCG (+hCG-beta) assays are the most reliable in diagnosis and follow-up

Human choriogonadotropin (hCG) and free hCG-beta values for 934 serum samples from patients with seminomatous or nonseminomatous testicular cancer were measured by highly specific immunoradiometric assays (IRMAS). In non-seminoma samples, hCG and hCG-beta were highly correlated (r = 0.82, P less than 0.001). Of 112 "marker-positive" seminoma samples, only 46 (41.1%) showed both increased hCG and hCG-beta. In 39 cases (34.8%) only hCG-beta and in 27 cases (24.1%) only dimer-hCG was increased. This makes the determination of hCG and hCG-beta, either by two assays or by a single hCG (+hCG-beta) assay, most reliable in these patients. For all samples, hCG (+hCG-beta) was measured by a polyclonal RIA and a monoclonal IRMA, which differed in their cross-reactivities with hCG-beta (234% and 720%, respectively). The hCG (+hCG-beta) IRMA, as a result of its higher hCG-beta cross-reactivity, was superior to the hCG (+hCG-beta) RIA in detecting slightly increased hCG-beta. Additionally, 11 widely used commercial hCG kits were tested for their hCG-beta cross-reactivities and showed values between less than 3% and 264%.

Steroidogenesis in an estrogen-producing adrenal tumor in a young woman: comparison with steroid profiles associated with cortisol- and androgen-producing tumors

There is only one previous report of an estrogen-secreting adrenal tumor occurring in a woman during reproductive years. Our patient presented with mild hirsutism associated with menstrual bleeding every 3-6 weeks. The occurrence of apparently intermenstrual bleeding prompted an evaluation of estrogen levels. Markedly elevated plasma estrone levels were found (860-2305 pmol/L; normal, 50-340). Lesser relative elevations in 11-deoxycortisol and androstenedione were noted. Computed tomographic scanning of the adrenal glands identified a large tumor, which was subsequently resected. Estrone levels fell to 120 pmol/L, and all other abnormalities were corrected. Eighteen months after adrenalectomy, ovulation occurred regularly, and steroid levels were entirely normal. Steroid production in a cell suspension made from tissue obtained from the 190-g tumor was compared with that occurring in normal human adrenal cells. The production of estrone by the tumor cells was 40-fold greater than that by normal adrenal cells. There was also a mild excess of 11-deoxycortisol produced by tumor cells, but the tumor cells were less than 50% as efficient as normal cells in producing cortisol, dehydroepiandrosterone, androstenedione, testosterone, and dehydroepiandrosterone sulfate. Examination of the steroid profile in plasma occurring in three other patients with adrenal tumors reveals that while elevations in estrone occur frequently, this is usually due to the peripheral conversion of very high levels of androstenedione. Estrone, androstenedione, and 11-deoxycortisol plasma levels were elevated in all four patients; dehydroepiandrosterone sulfate was elevated in only two of four patients. After resection of one of these tumors, all steroid levels remained normal despite the occurrence of extensive metastases. These observations confirm the difficulty of making a diagnosis of estrogen excess in a woman during reproductive years because of the paucity of physical signs. The acquisition of aromatase activity was clearly demonstrated by tumor cells from our patient in vitro. Elevated plasma concentrations of estrone, androstenedione, and 11-deoxycortisol provide useful markers for adrenal tumors, but no one steroid can be relied upon in all tumors, and metastases may lack the steroidogenic capabilities of the primary tumor.

Increased serum levels of a parathyroid hormone-like protein in malignancy-associated hypercalcemia

STUDY OBJECTIVE

To measure the serum levels of a newly described parathyroid hormone-like protein (PLP) which was isolated from malignant tumors associated with hypercalcemia, and determine whether PLP is a humoral factor in malignancy-associated hypercalcemia.

DESIGN

A cross-sectional study of serum levels of PLP using a newly developed radioimmunoassay.

SETTING

A university-affiliated Veterans Administration hospital in San Francisco, California, a University hospital in Hong Kong, and a private hospital in Danville, Pennsylvania.

PATIENTS

Patients with hypercalcemia (calcium greater than 2.65 mmol/L) and a diagnosis of malignancy were studied. Control groups included normocalcemic patients with malignancy, patients with hyperparathyroidism, and normal subjects.

MEASUREMENTS AND MAIN RESULTS

Serum immunoreactive PLP (iPLP) levels in normal subjects were less than 2.5 pmol eq/L (10 pg/mL), and 68% of subjects had undetectable levels. The serum concentration of iPLP was normal in 15 of 16 hypercalcemic patients with hyperparathyroidism. Serum iPLP was increased (greater than 2.5 pmol eq/L) in 36 of 65 (55%) patients with malignancy-associated hypercalcemia, with a mean value of 6.1 +/- 0.9 pmol eq/L (24 pg/mL). In a subgroup of patients with solid tumors serum iPLP was increased in 30 (71%) of 42 hypercalcemic patients, with a mean value of 6.5 +/- 0.9 pmol eq/L. Serum iPLP was elevated in only 3 of 23 normocalcemic patients with cancer. In patients with solid malignancies (n = 59), levels of iPLP were positively correlated with the total serum calcium (r = 0.43, P less than 0.01).

CONCLUSION

The data indicate a relation between the serum concentration of iPLP and the presence of hypercalcemia in solid malignancies. The results support a role for PLP as a humoral mediator of hypercalcemia in most patients with solid tumors. Measurement of iPLP should be useful in the differential diagnosis of hypercalcemia.

[Tumor markers in endocrinology (without gynecology and urology)]

In tumours of the endocrine system there are very few real "tumour markers" (e.g. CEA); all other relevant tests measure by radioassay several endocrine materials which are produced in similar ways by tumours and normal glands. Therefore, tumour marker assays in endocrinology are usually performed in follow-up studies after more or less radical therapy of tumours of the pituitary gland, thyroid gland, parathyroid glands, endocrine pancreas and the adrenal glands. On the basis of approximately 3000 assays of HGH, prolactin, thyroglobulin, calcitonin, CEA, insulin, gastrin, cortisol and aldosterone (in part with suppression and/or stimulation techniques), it is shown that these mostly indirect tumour marker assays are very important in follow-up programmes after therapy of neoplasms of the endocrine system. Their sensitivity amounts to 80%, their specificity is of the same degree.

Cushing's syndrome due to ACTH-production of an ovarian carcinoid

The case of a 56-year old woman with severe Cushing's syndrome due to ovarian ACTH-production is described. Both clinical picture and biochemical pattern were consistent with the ectopic ACTH syndrome. ACTH was found by specific immunohistochemical staining in a carcinoid tumor of the patient's right ovary. In contrast, pituitary cells exhibited immunoreactive ACTH to only a minimum extent.

Increased insulin-like growth factor II production and consequent suppression of growth hormone secretion: a dual mechanism for tumor-induced hypoglycemia

We investigated the pathophysiology of fasting hypoglycemia associated with large tumors of mesenchymal origin. We studied two patients with symptomatic fasting hypoglycemia (plasma glucose, 1.92 and 2.03 mmol/L) and a large mesenchymal neoplasm. Before therapy, the plasma insulin-like growth factor II (IGF-II) level measured by RIA was elevated (1879 and 1084 micrograms/L; normal range, 358-854 micrograms/L), the serum GH response to hypoglycemia was impaired, and the plasma IGF-I level was low in both patients. After treatment of the tumor, all of these abnormalities resolved in both patients. Northern blot analysis of tumor RNA revealed extremely high levels of IGF-II mRNA (greater than 100-fold higher than those in normal adult liver). Tumor fragments released IGF-II into tissue culture medium (2.1 and 7.2 micrograms IGF-II/g tissue.24 h). These findings indicate that secretion of IGF-II into the circulation by the tumor was the likely source of the elevated plasma IGF-II levels. We suggest that the primary event in tumor-induced hypoglycemia is overproduction of IGF-II by the tumor, which gives rise to hypoglycemia by a dual mechanism: increased glucose utilization mediated by the insulin-like actions of IGF-II and inhibition of GH secretion.

Humoral hypercalcemia in Hodgkin's disease. Clinical and laboratory evaluation

To provide further understanding of humoral hypercalcemia in Hodgkin's disease (HD) the authors describe the clinical features and laboratory investigation of three patients recently treated at Massachusetts General Hospital. All were middle-aged men who presented with symptomatic hypercalcemia which led to a diagnosis of bulky intraabdominal HD. None had evidence of bone involvement or hyperparathyroidism. In the two cases tested 1,25(OH)2D3 was elevated at the time of diagnosis. These characteristics are remarkably similar to those of ten patients with HD and probable humoral hypercalcemia described in the literature. The diagnosis of HD was supported in Cases 1 and 3 by genomic blot analysis which showed no evidence of T-cell or B-cell tumor origin. In an in vitro assay, primary tumor medium from Case 1 stimulated dose-dependent bone resorption which was not entirely ascribable to 1,25(OH)2D3. The authors conclude that humoral hypercalcemia in HD predominantly affects males of middle age, that intraabdominal bulky disease is common, and that hypercalcemia appears to be mediated by tumor related production of 1,25(OH)2D3 in concert with a second factor.

[Effect of sex steroids on the lipoprotein profile]

Hyperandrogenemia is associated with relatively high LDL- and low HDL-cholesterol levels, increasing the risk of the development of arteriosclerotic disease. In three women suffering from androgen producing ovarian tumors, this observation could be confirmed. After surgical removal of the ovaries, lipoprotein profiles returned to normal. In contrast, androgens did not affect lipoproteins in two testicular feminized individuals. Despite elevated testosterone levels, the lipoprotein profiles were absolutely normal. This observation indicates that the affects on the lipoprotein profile is receptor mediated.

Neurophysins as tumor markers for small cell carcinoma of the lung. A cancer and Leukemia Group B evaluation

Plasma human neurophysins (HNPs) were evaluated as tumor markers for patients with small cell carcinoma of the lung (SCCL) who were entered on limited disease and extensive disease treatment trials conducted by Cancer and Acute Leukemia Group B (CALGB). HNP values obtained before treatment showed 44% of tumors secreting vasopressin-associated HNP (VP-HNP), 14% secreting oxytocin-associated HNP (OT-HNP), and 11% producing both HNPs. There was a significantly higher incidence of HNP-secreting tumors for patients with extensive disease and two or more metastatic lesions than for patients with limited disease. There were no clear differences in response to treatment or in survival between patients with HNP-secreting tumors and those with nonsecreting tumors. Response to treatment evaluated by the change in plasma HNP, gave a 91% agreement with independently derived clinical impressions. Our data indicates that HNP evaluations provide sufficient sensitivity to forecast clinical response when it cannot be clearly assessed by conventional methods.

Adenosquamous carcinoma of the colon presenting with hypercalcemia

A rare adenosquamous carcinoma of the colon occurred in a 41-year-old patient. Its presentation with hypercalcemia, in the absence of osseous metastases, has not been described previously. The hypercalcemia in this case was due to the elaboration of a parathyroid hormone-like substance by the tumor. The general characteristics of primary adenosquamous and squamous cell carcinomas of the colon are presented. These tumors present with advanced disease, in younger patients, and follow a highly aggressive course, as compared with adenocarcinomas of the colon. The cause of the malignancies, in the light of current theories regarding their genesis, is discussed.

Testicular failure in patients with extragonadal germ cell tumors

Eight patients with mediastinal or retroperitoneal germ cell tumors who had undergone testicular biopsy or orchiectomy were retrospectively analyzed for primary testicular abnormalities, subfertility, and abnormal sex hormone levels. Testicular tissue was abnormal in all patients, revealing peritubular fibrosis (six), decreased spermatogenesis (eight), interstitial edema (five), Sertoli cells only (one), and Leydig cell hyperplasia (two). Detailed hormone analysis in five patients revealed elevations of luteinizing hormone in four, decreased serum testosterone in two, elevations of estradiol in two, and elevation of human chorionic gonadotropin in one patient. A history of infertility was documented 2 months to 13 years before presentation in four patients and suspected in another. Extragonadal germ cell tumors, like their testicular counterparts are associated with primary germ cell defects, some of which seem to be independent of gonadotropin production by the tumor. In addition, the rather high incidence of antecedent infertility suggests that either a congenital or acquired primary germ cell defect contributes to defective spermatogenesis and the development of cancer in incompletely migrated germ cells.

Hyperthyroidism and high serum levels of TSH associated with pituitary tumour

We report a 28-year-old male with persistent clinical and laboratory findings of hyperthyroidism associated with marked elevated serum levels of TSH and no response to TRH despite hemithyroidectomy and subsequent antithyroid drug therapy two years previous to admission to our hospital. Subsequent skull X-rays, CT scans and angiographic findings demonstrated the presence of a pituitary tumour. After operation and radiation therapy T3, T4 and TSH levels returned to normal values. Seven years later the patient is still euthyroid. We conclude that hyperthyroidism in our patient was due to excessive secretion of TSH by the pituitary tumour.

[Paraneoplastic endocrinopathies]

After the presentation of the definition and of several historical data the present pathophysiological imaginations concerning the problems of the ectopic hormone production are sketched which nowadays not yet have accepted a definitive form. A survey of the at present ascertained paraneoplastic endocrinopathies and several own findings allow a valuation of the significance of these phenomena in practice, taking into consideration the literature.