Microwave ablation for large benign thyroid nodules: a proposal for a new approach: "the fluid-motion technique"

INTRODUCTION

Most thyroid nodules are benign, and treatment is primarily indicated for patients with symptoms or cosmetic concerns related to nodular volume. Recently, there has been growing interest in nonsurgical and minimally invasive techniques for the treatment of symptomatic benign thyroid nodules, including microwave ablation (MWA).

AIMS

This study aims to evaluate the effectiveness, efficacy, and safety of ultrasound-guided uncooled MWA in the treatment of benign symptomatic thyroid nodules, using a new ablation technique called the "fluid-motion technique."

MATERIALS AND METHODS

From April 2021 to February 2023, a total of 150 patients with benign thyroid nodules were treated using MWA at the Endocrine Surgery Unit of Pederzoli Hospital, Peschiera del Garda (Italy), with 102 of them being followed-up for at least 6 months.

RESULTS

Before treatment, the mean major diameter was 38.4 ± 10.0 mm, and the mean volume was 13.6 ± 10.5 mL. At 1 month, the mean volume was 6.8 ± 6.2 mL, and at 3 months, it was 4.6 ± 4.1 mL. The mean Volume Reduction Rate (VRR) at 3 months was 61.1 ± 22.0%. Of the nodules, 17 (17%), 65 (66%), and 20 (19%) had volumes ≤ 10, 10.1-20, and ≥ 20.1 mL, respectively. For these nodules, the mean VRR at 3 and 6 months was 55.3 ± 16%, 63.4 ± 24.8%, 72 ± 26.9% and 68.0 ± 11.2%, 73.5 ± 18.3%, and 81.6 ± 15.8%, respectively.

CONCLUSION

Our study shows that ultrasound-guided MWA is an effective and safe minimally invasive treatment for benign thyroid nodules. The goal is to achieve a VRR that can reduce symptoms and improve cosmetic appearance.

Lymphnode metastasis of thyroid cancer misinterpreted as lateral aberrant thyroid 40 years before identification of primary tumor. Case report and review of the literature

The differential diagnosis between lateral ectopic thyroid tissue with orthotopic normal gland and metastatic thyroid carcinoma is challenging. Lateral cervical site is a very rare location for ectopic tissue since only a few cases have been reported. The peculiarity of this clinical case is the finding of a thyroid carcinoma forty years after surgical resection of the ectopic thyroid lesion. This asynchronous association, never reported in literature, raises the question of the differential diagnosis between a true ectopic aberrant thyroid and an early lymph node metastasis from an occult thyroid carcinoma, evident in the primitive site many years later. Several elements, which will be matter of discussion, seem to favour the latter hypothesis. This case, although isolated, suggests that any lateral cervical mass, comprising thyroid tissue, should be regarded as a metastasis of thyroid carcinoma until proven otherwise. Carefull investigation of thyroid gland is mandatory.

Runx2 overexpression compromises bone quality in acromegalic patients

Acromegalic patients, characterized by excessive secretion of GH and IGF-1, show a high fracture risk but bone mineral density is a poor predictor for bone fractures in these patients. The effects of an excess of GH/IGF1 on skeleton as well as on osteogenic progenitors, i.e. mesenchymal stem cells, have not been investigated in these patients. We aimed to elucidate the skeletal conditions of acromegalic patients by means of bone microarchitecture analysis and evaluation of MSCs osteogenic commitment. In particular, we performed histomorphometric analyses, and we quantified the expression levels of the osteogenic transcription factor RUNX2 in circulating MSCs. Our results showed an abnormal microarchitecture and demonstrated that bone impairment in acromegalic patients is associated with the upregulation of RUNX2 expression. Furthermore, osteoblastic activity was significantly reduced in patients under pharmacological treatment, compared to untreated patients. In conclusion, this study demonstrates the key role of RUNX2 gene overexpression in causing bone impairment in acromegalic patients. It also suggests a therapeutic approach for the improvement of bone quality, focused on the osteoblastic lineage rather than the inhibition of osteoclastic activity.

Bone histomorphometry in acromegaly patients with fragility vertebral fractures

CONTEXT

The high risk of vertebral fractures (VFs) in acromegaly patients despite normal bone mineral density (BMD) is well known. The reasons for this paradoxical finding of skeleton fragility are poorly understood due to the limited data on bone histomorphometry in acromegaly.

OBJECTIVE

This study aimed to analyze histomorphometric parameters including bone microarchitecture in acromegaly patients with VFs and normal BMD compared to normal subjects, and also to evaluate the differences between active and controlled acromegaly patients.

PATIENTS AND METHODS

Forty-seven acromegaly patients (17 active, 30 controlled), median (range) age 57 years (30-88) were evaluated for bone turnover, morphometric VFs and BMD by dual-energy X-ray absorptiometry at lumbar spine and hip; 12 patients with VFs and normal BMD underwent iliac crest bone biopsy; 12 biopsies were taken at the autopsy in healthy sex and age-matched control subjects.

RESULTS

The histomorphometric evaluation of acromegaly fractured patients was compared with that of normal controls and showed significantly reduced median (range) levels of bone volume/tissue volume (BV/TV: 15.37% (7.93-26.75) vs. 18.61% (11.75-27.31), p = 0.036), trabecular thickness (TbTh: 77.6 µm (61.7-88.3) vs. 82.7 µm (72.3-92.0) p = 0.045), with increased trabecular separation (TbSp: 536.4 µm (356.2-900.6) vs. 370.3 µm (377.1-546.3) p = 0.038) and increased cortical thickness (1268 μm (752-2521) vs. 1065 μm (851-1205) p = 0.025) and porosity (11.9% (10.2-13.3) vs. 4.8% (1.6-8.8) p = 0.0008). While active acromegaly patients showed histomophometric features of increased bone turnover, patients with controlled disease presented normal bone turnover with significantly lower osteoblastic activity, expressed as osteoblast number (p = 0.001), active osteoblasts and vigor (p = 0.014) in the presence of reduced osteocyte number (p = 0.008) compared to active disease.

CONCLUSIONS

The apparent paradox of bone fragility in acromegaly patients with a normal BMD can be explained by increased cortical thickness and porosity and reduced trabecular thickness with increased trabecular separation. These structural and microarchitectural abnormalities persist in the controlled phase of acromegaly despite bone turnover normalization. The main determinant of bone disease after hormonal control is severe osteoblastic dysfunction.

Prognostic factors in ectopic Cushing's syndrome due to neuroendocrine tumors: a multicenter study

OBJECTIVE

Evidence is limited regarding outcome of patients with ectopic Cushing's syndrome (ECS) due to neuroendocrine tumors (NETs).

DESIGN

We assessed the prognostic factors affecting the survival of patients with NETs and ECS.

METHODS

Retrospective analysis of clinicopathological features, severity of hormonal syndrome, treatments from a large cohort of patients with NETs and ECS collected from 17 Italian centers.

RESULTS

Our series included 110 patients, 58.2% female, with mean (±s.d.) age at diagnosis of 49.5 ± 15.9 years. The main sources of ectopic ACTH were bronchial carcinoids (BC) (40.9%), occult tumors (22.7%) and pancreatic (p)NETs (15.5%). Curative surgery was performed in 56.7% (70.2% of BC, 11% of pNETs). Overall survival was significantly higher in BC compared with pNETs and occult tumors (P = 0.033) and in G1-NETs compared with G2 and G3 (P = 0.007). Negative predictive factors for survival were severity of hypercortisolism (P < 0.02), hypokalemia (P = 0.001), diabetes mellitus (P = 0.0146) and distant metastases (P < 0.001). Improved survival was observed in patients who underwent NET removal (P < 0.001). Adrenalectomy improved short-term survival.

CONCLUSIONS

Multiple factors affect prognosis of ECS patients: type of NET, grading, distant metastases, severity of hypercortisolism, hypokalemia and diabetes mellitus. BCs have the highest curative surgical rate and better survival compared with occult tumors and pNETs. Hypercortisolism plays a primary role in affecting outcome and quality of life; therefore, prompt and vigorous treatment of hormonal excess by NET surgery and medical therapy should be a key therapeutic goal. In refractory cases, adrenalectomy should be considered as it affects outcome positively at least in the first 2 years.

Morphological study of upper airways and long-term follow-up of obstructive sleep apnea syndrome in acromegalic patients

Pathogenesis and long-term outcome of obstructive sleep apnea syndrome (OSAS) in acromegalic patients are still under debate. The aim of the study was to assess the prevalence and long-term follow-up of a series of acromegalic patients with OSAS and to investigate site, degree, and possible causes of upper airway obstruction by morphological study. Cross-sectional and longitudinal study was conducted in 58 acromegalic patients (33 active, 25 controlled) with polysomnography in all subjects, repeated in 25 patients with OSAS, and echocardiography. Morphological study including fiberoptic nasopharyngoscopy with the Müller maneuver (FNMM), magnetic resonance imaging (MRI), with 3-dimensional (3D) elaboration was also performed. The prevalence of OSAS was 58.6 % in the whole series: 63.6 % in the active group and 52 % in the controlled one. Left ventricular hypertrophy was more prevalent in patients with OSAS. OSAS improved in 62.5 % of active patients after achieving hormonal control, whereas it persisted or got worse in 66.6 % of the controlled ones. The uvula and tongue base were the main site of obstruction assessed by FNMM. Uvula diameters obtained by MRI study correlated with the severity of upper airway collapse assessed by FNMM and tongue measure with apnea-hypopnea index (p = 0.044). A greater narrowing and a smaller total volume of upper airways were confirmed by 3D-MRI in patients with more severe OSAS. Uvula and tongue hypertrophy plays a relevant role in the pathogenesis and severity of OSAS. Intensive treatment of acromegaly needs to be promptly adopted in order to reverse it.

Presentation, diagnostic features and glucose handling in a monocentric series of insulinomas

BACKGROUND

New aspects have emerged in the clinical and diagnostic scenarios of insulinoma: current guidelines have lowered the diagnostic insulin threshold to 3 μU/ml in the presence of hypoglycemia (<55 mg/dl); post-prandial hypoglycemia has been reported as the only presenting symptom; preexisting diabetes mellitus (DM) was recognized in some patients.

AIM

To evaluate clinical features, diagnostic criteria and glucose metabolic profile in a monocentric series of patients affected by insulinomas including two subgroups: sporadic and multiple endocrine neoplasia type-1 syndrome (MEN-1).

SUBJECTS AND METHODS

Clinical, pathological and biochemical data regarding 33 patients were analyzed.

RESULTS

following the current guidelines the 72-h fasting test was initially positive in all cases but one. In this case the test, initially negative, became positive after a 2-yr follow-up. Nadir insulin level was ≥ 3 μU/ml but <6 μU/ml in 3 patients and ≥ 6 μU/ml in the remaining 30 cases. At presentation, 27 patients (82%) reported only fasting symptoms, 3 (9%) only post-prandial and 3 (9%) both. Seven cases (21%) had previously been affected by type 2 DM or impaired glucose metabolism.

CONCLUSIONS

In our series the new cut-off of insulin increased the sensitivity of the 72-h fasting test from 87% to 97%. The absence of hypoglycemia during the test cannot definitively rule out the diagnosis and the test should be repeated in every highly suspicious case. Post-prandial hypoglycemia can be the only presenting symptom. DM may be associated with the occurrence of insulinoma. So that a possible diagnosis of insulinoma must not be ignored if previous impaired glucose handling is evident.

Natural history of gastro-entero-pancreatic and thoracic neuroendocrine tumors. Data from a large prospective and retrospective Italian epidemiological study: the NET management study

BACKGROUND

The few epidemiological data available in literature on neuroendocrine tumors (NET) are mainly based on Registry databases, missing therefore details on their clinical and natural history.

AIM

To investigate epidemiology, clinical presentation, and natural history of NET.

DESIGN AND SETTING

A large national retrospective survey was conducted in 13 Italian referral centers. Among 1203 NET, 820 originating in the thorax (T-NET), in the gastro-enteropancreatic tract (GEP-NET) or metastatic NET of unknown primary origin (U-NET) were enrolled in the study.

RESULTS

93% had a sporadic and 7% a multiple endocrine neoplasia type 1 (MEN1)-associated tumor; 63% were GEP-NET, 33% T-NET, 4% U-NET. Pancreas and lung were the commonest primary sites. Poorly differentiated carcinomas were <10%, all sporadic. The incidence of NET had a linear increase from 1990 to 2007 in all the centers. The mean age at diagnosis was 60.0 ± 16.4 yr, significantly anticipated in MEN1 patients (47.7 ± 16.5 yr). Association with cigarette smoking and other non-NET cancer were more prevalent than in the general Italian population. The first symptoms of the disease were related to tumor burden in 46%, endocrine syndrome in 23%, while the diagnosis was fortuity in 29%. Insulin (37%) and serotonin (35%) were the most common hormonal hypersecretions. An advanced tumor stage was found in 42%, more frequently in the gut and thymus. No differences in the overall survival was observed between T-NET and GEP-NET and between sporadic and MEN1-associated tumors at 10 yr from diagnosis, while survival probability was dramatically reduced in U-NET.

CONCLUSIONS

The data obtained from this study furnish relevant information on epidemiology, natural history, and clinico-pathological features of NET, not available from the few published Register studies.

Runx2 mRNA expression in the tissue, serum, and circulating non-hematopoietic cells of patients with thyroid cancer

CONTEXT

Runx2, a master gene of osteogenic differentiation, is also expressed in nonosseous cancer cells. Microcalcifications are characteristic of papillary thyroid carcinoma and represent a useful find for diagnosis. However, the molecular expression of osteogenic differentiation transcription factor Runx2 has been poorly investigated in this tumor.

OBJECTIVE

The aim of this study was to investigate Runx2 mRNA expression in normal and pathological thyroid tissue, serum, and circulating non-hematopoietic cells.

SETTING

The study was performed in the Endocrine Unit of Internal Medicine of "Azienda Ospedaliera Universitaria Integrata of Verona" (Verona, Italy).

PATIENTS

We enrolled 12 patients with a papillary thyroid carcinoma (PTC), who had undergone total thyroidectomy performed by the same surgeon. The results, obtained by real-time RT-PCR, were compared with biological samples obtained from 13 sex- and age-matched normal donors.

RESULTS

Our data demonstrated that Runx2 mRNA is overexpressed (7.81-fold expression) in pathological thyroid tissue than in normal tissue (P < 0.05). Runx2 mRNA overexpression was also observed in serum and circulating non-hematopoietic cells of PTC patients with respect to normal donors (5.91-fold expression, P < 0.001; 3.82-fold expression, P < 0.05, respectively). We also observed that patients with microcalcifications expressed significantly higher levels of Runx2 mRNA in serum with respect to patients without microcalcifications (P < 0.05).

CONCLUSION

This study can open up new research perspectives in the diagnosis and follow-up of PTC, even if further and larger cohort studies will be necessary to validate the Runx2 expression as biomarkers in thyroid cancer.

Presentation and outcome of pancreaticoduodenal endocrine tumors in multiple endocrine neoplasia type 1 syndrome

AIM

To assess presentation and outcome of pancreaticoduodenal endocrine tumors (PDETs) in a single center series of multiple endocrine neoplasia type 1 (MEN1) patients.

METHODS

Retrospective analysis of prospectively collected data of MEN1 patients observed at the University of Verona.

RESULTS

Thirty-one MEN1 patients had PDETs, including 16 nonfunctioning (NF), 6 insulinomas and 9 Zollinger-Ellison syndrome (ZES). In 16 of these patients (52%), PDET was the manifestation which led to the diagnosis of MEN1; among this group, 15 patients (94%) previously had unidentified primary hyperparathyroidism (PHPT), which was asymptomatic in 9 cases (60%). Of the 31 patients, 19 (61%) underwent curativesurgery and 13 (68%, 7 NF-PDETs, 4 insulinomas and 2 ZES) were disease-free after a median follow-up of 3 years (range: 0.5-15). One patient had debulking surgery with stable disease after 2 years of follow-up. Eight patients with NF-PDETs ≤20 mm and 2 with ZES, treated with a conservative approach, showed stable disease. One patient with insulinoma was lost to follow-up.

CONCLUSIONS

PDET may be the manifestation that leads to MEN1 diagnosis since the almost constant presence of PHPT is very often unrecognized or considered sporadic. Conversely, the presence of PDETs should be looked for in all patients presenting PHPT, even if asymptomatic, particularly before age 50. Surgery may be curative in the majority of insulinomas and can prolong disease-free survival in NF-PDET, but is not proven to be effective in ZES. A conservative approach can be safely reserved for patients with NF-PDETs ≤20 mm.

Multiple endocrine neoplasia type 2 syndromes (MEN 2): results from the ItaMEN network analysis on the prevalence of different genotypes and phenotypes

OBJECTIVE

Multiple endocrine neoplasia type 2 (MEN 2) is a genetic disease characterized by medullary thyroid carcinoma (MTC) associated (MEN 2A and 2B) or not familial MTC (FMTC) with other endocrine neoplasia due to germline RET gene mutations. The prevalence of these rare genetic diseases and their corresponding RET mutations are unknown due to the small size of the study population.

METHODS

We collected data on germline RET mutations of 250 families with hereditary MTC followed in 20 different Italian centres.

RESULTS AND CONCLUSIONS

The most frequent RET amino acid substitution was Val804Met (19.6%) followed by Cys634Arg (13.6%). A total of 40 different germline RET mutations were present. Six families (2.4%) were negative for germline RET mutations. The comparison of the prevalence of RET germline mutations in the present study with those published by other European studies showed a higher prevalence of Val804Met and Ser891Ala mutations and a lower prevalence of Leu790Phe and Tyr791Phe (P<0.0001). A statistically significant higher prevalence of mutations affecting non-cysteine codons was also found (P<0.0001). Furthermore, the phenotype data collection showed an unexpected higher prevalence of FMTC (57.6%) with respect to other MEN 2 syndromes (34% MEN 2A and 6.8% of MEN 2B). In conclusion, we observed a statistically significant different pattern of RET mutations in Italian MEN 2 families with respect to other European studies and a higher prevalence of FMTC phenotype. The different ethnic origins of the patients and the particular attention given to analysing apparently sporadic MTC for RET germline mutations may explain these findings.

Chromosome translocation frequency after radioiodine thyroid remnant ablation: a comparison between recombinant human thyrotropin stimulation and prolonged levothyroxine withdrawal

BACKGROUND

Thyroid remnant ablation of differentiated thyroid carcinoma (DTC) patients is traditionally performed after levothyroxine withdrawal. Recombinant human TSH (rhTSH) administration increases serum TSH levels without inducing hypothyroidism.

AIM

The aim of the study was to investigate the frequency of chromosome translocations in DTC patients after the first (131)I therapeutic dose and compare the frequency of translocations between DTC patients off levothyroxine and those receiving rhTSH.

PATIENTS AND METHODS

A total of 20 DTC patients were randomly assigned to levothyroxine withdrawal [(30 d) group A; n=10, nine women; mean age 48.5+/- 19.2 yr] or rhTSH injections [(0.9 mg im per 2 consecutive days) group B; n=10, eight women; mean age 50.4+/- 18.8 yr] before undergoing (131)I activity (3.7 GBq). The frequency of translocations in peripheral lymphocytes was analyzed by tricolor fluorescence in situ hybridization with whole-chromosome-specific probes for chromosomes 1, 4, and 8. Lymphocytes were stained routinely (about 500 each time).

RESULTS

The two groups showed similar baseline translocation frequency. After (131)I administration, the total chromosomal translocation rate was significantly lower in group B than group A (P = 0.02). The frequency of translocations increased significantly in group A only (P = 0.01 vs. baseline). Rearrangement specifically involved chromosomes 4 and 8 (P = 0.02 vs. baseline).

CONCLUSIONS

Our preliminary data show that in hypothyroid status (131)I ablation therapy induces a higher translocation rate, especially in chromosomes 4 and 8. This finding, in agreement with previous dosimetric reports, suggests that whereas inducing a low extrathyroid exposure, rhTSH reduces the potential risk of chromosomal aberration associated with blood irradiation.

Sleep apnoea syndrome is highly prevalent in acromegaly and only partially reversible after biochemical control of the disease

BACKGROUND

Whether sleep apnoea syndrome (SAS) subsides after biochemical and clinical remission of acromegaly is controversial.

OBJECTIVE

To assess the presence of SAS in a cohort of acromegalic patients, which included a subgroup with active disease and a subgroup in remission, and to evaluate clinical and biochemical independent predictors of SAS.

DESIGN

Cross-sectional and longitudinal study.

SETTING

Italian university department of internal medicine.

PATIENTS

About 36 acromegalic patients: 18 active and 18 controlled.

MEASUREMENTS

Polysomnography was performed in all patients and repeated in six with active acromegaly and SAS after achieving disease control. Echocardiographic parameters were also measured.

RESULTS

The prevalence of SAS was 47% in the overall acromegalic population: 56% in the active group and 39% in the controlled one. In a multivariate analysis IGF1, male gender, age, body mass index, and disease duration were associated with SAS. Impaired glucose tolerance or diabetes was more prevalent in patients with SAS, particularly in the severe cases. Among the six patients of the longitudinal study, five showed improvement of SAS, but none recovered. No correlation was found between echocardiographic parameters and severity of SAS.

CONCLUSION

SAS can persist after recovery of acromegaly in several patients. Given the negative prognostic significance of this respiratory disorder, polysomnography should be included as routine procedure in the work-up of the acromegaly, even if in remission, being mandatory in those patients considered at high risk (elderly males, overweight, diabetic). Appropriate intensive treatment should be implemented to minimize the clinical impact of SAS in acromegaly.

Multidisciplinary approach including receptor radionuclide therapy with 90Y-DOTATOC ([90Y-DOTA0, Tyr3]-octreotide) and 177Lu-DOTATATE ([177Lu-DOTA0, Tyr3]-octreotate) in ectopic cushing syndrome from a metastatic gastrinoma: a promising proposal

OBJECTIVE

To present a case of a young woman with Cushing syndrome caused by ectopic production of adrenocorticotropic hormone from a metastatic pancreatic gastrin-secreting endocrine carcinoma, who had a good response to combination peptide receptor radionuclide therapy.

METHODS

We review the history, physical examination, laboratory investigations, and radiographic findings in this unusual patient. Moreover, the multimodal interventions are described and discussed.

RESULTS

In a 38-year-old woman with typical signs of cortisol excess, laboratory studies revealed diabetes mellitus, hypokalemia, and high levels of adrenocorticotropic hormone, plasma cortisol, and urinary cortisol. Abdominal computed tomography showed a 4-cm pancreatic mass and multiple metastatic lesions in the liver, and ectopic Cushing syndrome was diagnosed. Treatment consisted of surgical debulking of the tumor, ketoconazole, somatostatin analogues, chemoembolization of the liver metastatic lesions, and peptide receptor radionuclide therapy with the radiolabeled somatostatin analogues 90Y-DOTATOC ([90Y-DOTA0, Tyr3]-octreotide) and 177Lu-DOTATATE ([177Lu-DOTA0, Tyr3]-octreotate). The 5 1/2-year follow-up showed positive results, which included complete regression of all clinical and hormonal evidence of the tumor and substantial decrease in the size and number of hepatic metastatic lesions. The patient achieved and still maintains an optimal quality of life.

CONCLUSION

To the best of our knowledge, this is the first report of a multidisciplinary approach including peptide receptor radionuclide therapy with 90Y-DOTATOC and 177Lu-DOTATATE, which proved to be effective in improving clinical outcome in a case of metastatic endocrine carcinoma of the pancreas in conjunction with ectopic Cushing syndrome. In this unusual case, the patient has one of the longest durations of survival in this setting described in the literature.

Mechanisms of resistance to low-dose metronomic cyclophosphamide

13079

Background: It has been postulated that antiangiogenic therapies are less susceptible to acquired resistance compared to conventional treatment strategies, which target genetically unstable tumor cells. However, resistance is commonly seen (pre)clinically. A better understanding of the underlying mechanisms is clearly needed to improve such therapies. Methods: We studied mechanisms of acquired resistance to low-dose metronomic (LDM) cyclophosphamide (CTX), the continuous or frequent administration of comparatively low doses of CTX with no extended breaks resulting primarily in antiangiogenic effects, by using LDM CTX relapsed/resistant variants obtained during prolonged in vivo therapy from the human prostate cancer cell line PC-3, which initially is highly responsive. The variants were analyzed for their growth characteristics, angiogenic “phenotype” and impact on circulating endothelial cells (CEC)/endothelial cell progenitors (CEP). Furthermore, we obtained microvessel density (MVD) counts of corresponding xenografts and analyzed in vitro resistance to 4-hydroxycyclophosphamide (4-OH-CTX), hypoxia, acidosis, and glucose as well as serum deprivation. Results: The resistant variants did not show consistent changes in their angiogenic “phenotype”. The decrease in MVD upon LDM CTX treatment was comparable to that obtained in xenografts from parental PC-3, which was reflected by similar changes in the number of CEC and CEP. Despite in vivo resistance to LDM CTX, there was no evidence of in vitro resistance of the variants to 4-OH-CTX. However, they exhibited increased tolerance to microenvironmental stress resulting from sustained antiangiogenic activity. Conclusions: In this model, resistance to LDM CTX develops despite sustained antiangiogenic activity. This provides further evidence that reduced vascular dependence of the tumor cell population may be a basis for the observed resistance. The administration of CTX in a LDM manner does not result in tumor cell CTX resistance, supporting the notion that LDM protocols target primarily the tumor vasculature. If confirmed in ongoing clinical metronomic chemotherapy trials, our results will have major implications for the management of patients that progress under such treatment.

No significant financial relationships to disclose.

Carcinoid crisis induced by receptor radionuclide therapy with 90Y-DOTATOC in a case of liver metastases from bronchial neuroendocrine tumor (atypical carcinoid)

SS receptors are overexpressed in many tumors, mainly of neuroendocrine origin, thus enabling the treatment with SS analogs. The clinical experience of receptor radionuclide therapy with the new analog [90Y-DOTA0-Tyr3 ]-octreotide [90Y-DOTATOC] has been developed over the last decade and is gaining a pivotal role in the therapeutic workout of these tumors. It is well known that some procedures performed in diagnostic and therapeutic management of endocrine tumors, such as agobiopsy and hepatic chemoembolization, can be associated with the occurrence of symptoms related to the release of vasoactive amines and/or hormonal peptides from tumor cell lysis. This is the first report of a severe carcinoid crisis developed after receptor radionuclide therapy with 90Y-DOTATOC administered in a patient affected by liver metastases from bronchial neuroendocrine tumor (atypical carcinoid). Despite protection with H1 receptor antagonists, octreotide and corticosteroids, few days after the therapy the patient complained of persistent flushing of the face and upper trunk, severe labial and periocular oedema, diarrhoea and loss of appetite. These symptoms increased and required new hospitalisation. The patient received iv infusion of octreotide associated with H1 and H2 receptor antagonists and corticosteroid therapy, which induced symptom remission within few days. The case here reported confirms that radionuclide therapy is highly effective in determining early rupture of metastatic tissue and also suggests that pre-medication should be implemented before the radiopeptide administration associated with a close monitoring of the patient in the following days.

Long-term quiescence of ectopic Cushing's syndrome caused by pulmonary neuroendocrine tumor (typical carcinoid) and tumorlets: spontaneous remission or therapeutic effect of bromocriptine?

In 1990, a 55-yr-old woman was admitted to the Medical Department of our hospital for severe hypercortisolism complicated by secondary diabetes mellitus and serious hypokalemia. Although inferior petrosal sinus sampling did not show any significant difference between central and peripheral ACTH concentration, suggesting an ectopic source of ACTH secretion, diagnostic imaging was negative and Cushing's disease due to hyperplasia of the pituitary intermediate lobe was suspected. Medical treatment with bromocriptine and cyproheptadine led to a rapid and stabile normalization of adrenal function, so that after two months cyproheptadine was stopped and bromocriptine was tapered to a smaller dose. An attempt to discontinue medical treatment, carried out 3 yr later, was followed by a quick increase of ACTH and cortisol levels, which were normalized by the resumption of the bromocriptine. Adrenal function remained normal until 1994 when hypercortisolism relapsed despite the treatment. Chest radiography and computed tomography (CT) scan detected a 6 mm nodule in the middle lobe of the lung which proved to be a neuroendocrine tumor, with immunohistochemical positivity for ACTH. Nests of neuroendocrine cells (tumorlets) were also demonstrated in the surrounding lung tissue. After the lobectomy, the patient recovered completely from Cushing's syndrome and no symptoms and/or signs of recurrence have been observed over the subsequent follow-up period. Although cyclical spontaneous Cushing's syndrome could not be excluded, there was strong evidence that medical treatment with bromocriptine might have played a key role in long-lasting remission. To our knowledge, this is the second case described in literature of Cushing's syndrome caused by neuroendocrine lung tumor responsive to bromocriptine.

Cushing's syndrome induced by bronchopulmonary carcinoid tumours: a review of 98 cases and our experience of two cases

Bronchopulmonary carcinoids are one of the most common cause of ectopic secretion of corticotropin (ACTH) and account for approximately 1% of all the patients in whom Cushing's syndrome develops. We reviewed 98 cases described in the World Literature and we report on two new cases. A 60-year old woman affected by Cushing's syndrome underwent to surgical wedge resection of a peripheral pulmonary nodule and a 30-year old woman with similar clinical features underwent to middle lobectomy for a small hilar neoplasm. Histopathologic examination of the tumours defined them as typical bronchopulmonary carcinoids. The patients are asymptomatic and with no sign of recurrence 72 and 30 months after surgery. According to our review we found no clear evidence that bronchial carcinoids associated with Cushing's syndrome should be considered a more aggressive variant or subtype of the typical carcinoid. If Cushing's syndrome does not disappear after surgery, the presence of residual disease (often a nodal involvement) should be investigated. A long-term relapse of the syndrome requires a careful search for local or distant neoplastic recurrence.

Thyroxine hair content in congenital hypothyroidism and hyperthyroidism

Using the determination of thyroxine (T4) hair content, we studied 16 hypothyroid newborns diagnosed by means of our regional screening program, and five hypothyroid infants, undetected at birth, at diagnosis and after 3 months of substitutive therapy (8-10 microg/kg/day L-thyroxine in newborns; 15 microg/kg/day in infants), and 13 hyperthyroid adults. Hair T4 content was similar at diagnosis in hypothyroid newborns (2.6 +/- 2.3 pg/mg hair) and in infants undetected at birth (2.4 +/- 1.7 microg/mg hair), but very high only in the latter after therapy (23.2 +/- 3.9 microg/mg hair). Untreated hyperthyroid adults surprisingly evidenced lower hair T4 (0.4 +/- 0.2 microg/mg hair) than controls (1.5 +/- 0.3 microg/mg hair). We suggest these findings are due to differential tissue storage of thyroid hormone, related to the different blood T4 concentration. Therefore, T4 hair assay could be a non-invasive method to further assess thyroid status.

An unusual case of Cushing's syndrome due to ACTH-independent macronodular adrenal hyperplasia

We report a case of Cushing's syndrome due to ACTH-independent macro-nodular adrenal hyperplasia (AIMAH). The patient, a 51-year-old man, had been suffering from poorly controlled arterial hypertension for the previous 6 years and he complained of progressive weight gain, gynecomastia and impotence. Physical examination revealed classic cushingoid features. Endocrine basal assessment showed increased urinary free cortisol (264-600 micrograms/24 hr). Urinary steroid profile showed an increase of total 17-hydroxycorticosteroids (17-OHCS: 23 mg/24 hr), with a threefold increase of tetrahydrocortisol (THF:9.66 mg/24 hr) and of tetrahydrocorticosterone (THB: 1.35 mg/24 hr). Tetrahydrodesossicortisol was only slightly elevated (THS:0.67 mg/24 hr) and tetrahydrodesossicorticosterone was at the inferior limit of the normal range (THDOC: 0.03 mg/24 hr). Total 17-ketosteroids were decreased (17-KS: 3 mg/24 hr). Plasma cortisol level was elevated and without circadian rhythm (26-29 micrograms/dl in the morning, 26-28 micrograms/dl at 24:00 h). DHEAs and free testosterone levels were significantly reduced (106 ng/dl and 3.9 pg/ml respectively). ACTH was undetectable and unresponsive to CRH. Both dexamethasone and octreotide failed to suppress plasma cortisol levels. Abdomen computed tomography scan demonstrated bilaterally enlarged multinodular adrenal glands. Cerebral magnetic resonance revealed no alteration of the pituitary gland. The patient underwent bilateral adrenalectomy. On macroscopic examination, adrenal glands were occupied by multiple yellow nodules and their compressive weight was 190 g, with left adrenal heavier than the right one (120 g and 70 g respectively). Histologically, nodular lesions were predominantly composed of large clear cells, with small foci of "hybrid" cells and adipose tissue metaplasia. Reticularis zone was atrophic. In the immediate post-operatory course pulmonary embolism occurred, despite prophylaxis with low molecular weight heparin. After having recovered from this complication, the patient showed progressive regression of cushingoid status. The findings of increased THF/THS and THB/THDOC ratios were in agreement with a relative hyperfunction of 11-beta-hydroxylase "in vivo", which might have contributed to the hypercortisolism, in addition to the marked increase of secernent adrenal mass.

Identification of changes in gene expression associated with minimal residual disease

Minimal residual disease (MRD), the tumour burden which remains after a course of treatment that has resulted in clinical remission [1], appears to differ in certain characteristics from the primary tumour population. Certainly the cells which comprise MRD have had to escape from the constraints of the primary tumour mass, invade normal tissue and penetrate small vessels in order to enter the circulation in which they then have had to survive. Such activities are the consequence of the expression of specific proteins and these may well be a reflection of alterations in DNA or RNA levels. Identifying the changes in RNA expression levels between related cell groups exhibiting different phenotypes recently has become a great deal easier as a consequence of developments in analytical procedures such as Differential Display (DD) and Serial Analysis of Gene Expression (SAGE). Application of these procedures to MRD cells recovered from blood, bone marrow or lymph node, should identify novel sequences associated with tumour progression and the development of disseminated disease.

Identification by differential display of a protein phosphatase-2A regulatory subunit preferentially expressed in malignant melanoma cells

We described the occurrence of 4 transcripts differentially displayed between syngeneic murine B16F10 (metastatic melanoma) and Melan-a (immortalised melanocytes) cell lines. We now report that one such transcript, which is B16F10-specific, represents a protein phosphatase-2A B' regulatory subunit. No expression of this transcript was detected in the weakly metastatic B16F1 by Northern blotting. Moreover, the transcript was not expressed by spontaneously immortalised, non-tumorigenic, melanocytes (Melan-Ab and Melan-a2), nor was it expressed by ras-transformed, tumourigenic melanocytes (Melan-Ab-LTR-ras). Cloning of the 5'-end region of this transcript (termed band 8A) from B16F10 cells revealed an intracisternal A-particle insertion, including the long terminal repeat region, which could account for the observed high expression in B16F10 cells. Single cell clones of B16F10 manifested an experimental metastasis capacity, which correlated with band 8A expression with the lowest expressors being least metastatic. The human homologue of the B' regulatory subunit, B56gamma, is expressed preferentially at the mRNA level in human melanoma cell lines compared with normal epidermal melanocytes. In situ hybridisation studies on human clinical samples detected high expression of this gene in a number of malignant melanomas. Our results imply strongly that this protein phosphatase-2A regulatory subunit may have a role in melanoma tumour progression.

The TSH-dependent variation of the essential elements iodine, selenium and zinc within human thyroid tissues

Instrumental Neutron Activation Analysis was used in order to measure iodine, selenium and zinc concentration in thyroid samples. A pair of samples of normal and nodular tissue were collected from the thyroid gland from 72 patients selected on the basis of pathological criteria (44 cases of multinodular goiter, 12 of chronic lymphocytic thyroiditis (CLT), 6 of thyroid adenoma (TA) and 12 of thyroid cancer (TC)). The check for tissue homogeneity and sampling error was performed by means of the coefficient of variation (CV%) of the elements in replicate samples of normal and altered tissues. High CV% values (> 15%) for iodine reflected a functional variability in thyroid follicles, while low CV% values (< 10%) for selenium and zinc indicated that the composition of selected tissues was rather homogeneous. The variation of the element's concentration was compared in normal and altered tissues. The mean element concentrations had values close to those already reported in the literature; furthermore, our patients had marginal iodine and selenium deficiency. Both normal and nodular tissues in CLT showed statistically significant lower zinc values as compared with the other thyroid diseases. To evaluate the thyroid function, thyroid stimulating hormone (TSH) and thyroxine (T4) levels were measured in the serum of patients. Two arbitrary serum-TSH threshold levels (TSH < 1.0 and > 4.0 mU/L) were introduced in order to classify, respectively, hyperthyroidism and hypothyroidism, as well as euthyroid conditions (1.0 < TSH < 4.0 mU/L), and each patient was assigned to one of these groups. The influence of TSH in the variation of the concentration of iodine, selenium and zinc in normal and altered human thyroid tissues was significant.

Heterogeneity of nuclear DNA pattern and its relationship with cell cycle activity parameters in multinodular goitre

OBJECTIVE

Recent studies suggest that the malignancy rate in multinodular goitre is not significantly different from that observed in solitary nodules and that chromosomal aberrations are not infrequent in multinodular goitre. To further investigate this topic we determined the DNA pattern in multinodular goitres.

DESIGN

DNA ploidy and cell cycle activity parameters were determined in multinodular goitres.

PATIENTS

We evaluated 235 patients (185 female, 50 male, mean age 52 +/- 13 years), who had undergone thyroidectomy; 11 of them harboured occult differentiated microcarcinoma.

MEASUREMENTS

DNA index (DI), coefficient of variation of G0/G1 phase (CV), percentage of cells in S phase (%S) and in G2+M phase (%G2-M) and proliferative index (PI = %S+%G2-M) were determined by flow cytometric analysis (FCM) in tissue samples taken from 3 different areas of the thyroid gland.

RESULTS

Aneuploid DNA was found in 50 goitres without carcinoma (22.3%) and in 5 goitres with carcinoma (45.5%). The mean PI of euploid cells in the goitre without carcinoma was significantly higher in the goitres with an aneuploid component compared to the goitres without aneuploidy (10.8 +/- 1.3 SEM vs 6 +/- 0.32; P +/- 0.001). Also, the percentage difference between maximal and minimal PI found within each goitre (delta PI %) was higher in the former group (373 +/- 49 SEM vs 142 +/- 11.3; P < 0.0001). The PI was significantly higher in goitres with carcinoma compared to the goitres without carcinoma (12.9 +/- 3.2 SEM vs 7.07 +/- 0.40; P < 0.05).

CONCLUSIONS

The findings of increased proliferation rate in goitres with an aneuploid or neoplastic component suggests that some factors involved in goitrogenesis could also be responsible for the development of chromosomal aberrations and/or for the selection of cellular clones endowed with high growth potential.

[Cushing's disease associated with empty sella: a clinical case treated for years with ketoconazole]

Cushing's disease and empty sella without evidence of pituitary adenoma are rarely observed. To our knowledge, there is very little documentation on long-term therapeutic follow-up with the steroidogenesis inhibitor ketoconazole. A 48-year-old woman with uncontrolled insulin-dependent diabetes mellitus, severe hypertension, and clinical findings of hypercortisolism was referred to our hospital. Endocrine evaluation of adrenocortical function evidenced hypothalamic-pituitary-hypercortisolism, and excluded adrenal tumor or an ectopic corticotropin source. Magnetic resonance imaging disclosed an empty sella turcica but not pituitary adenoma. The patient was treated with a steroidogenesis inhibitor, ketoconazole (600 mg daily) which reduced urinary cortisol excretion to within the normal range. Serum cortisol levels also returned to normal in the morning but not in the evening. The patient has continued on ketoconazole therapy for the past 7 years, with neither side effects nor tachyphylaxis. The reduction of cortisol secretion brought about significantly improved control of diabetes mellitus and hypertension, although signs of hypercortisolism have persisted. Radiographic studies of the hypophysis during follow-up have not evidenced adenoma.

Identification by differential display of annexin-VI, a gene differentially expressed during melanoma progression

To identify genes involved in the melanocyte to malignant melanoma conversion, we have applied differential display to the comparison of syngeneic murine B16F10 (metastatic melanoma) and Melan-a-immortalized melanocyte cell lines. Approximately 7000 bands were analyzed, revealing approximately 80 to be differentially displayed. Reverse Northern blotting and subsequent Northern blotting confirmed the reproducible differential expression of four transcripts. Three B16F10-specific bands encode novel genes or partially sequenced cDNAs of unknown function. One Melan-a-specific band was found to be identical to the 3' end region of the mouse Annexin VI mRNA and shown to have a reduced message expression in B16F10 relative to Melan-a. Differential expression was confirmed at the protein level with Western blotting using a rabbit polyclonal antiserum. Immunohistochemistry of human melanoma specimens with this antiserum revealed a decrease or loss of Annexin VI expression as melanomas progressed from a benign to a more malignant phenotype. Our results provide further evidence for a potential role of Annexin VI in tumor suppression.

An unusual case of adrenal failure due to isolated metastases of breast cancer

We describe a patient affected by adrenal insufficiency due to metastases of breast cancer. Adrenal involvement became clinically evident 20 years after radical mastectomy and it was the only secondary localization of the tumor. There is still no evidence of other metastases after a two year follow-up. This case suggests that adrenal function evaluation should be included in periodical follow-ups of patients who underwent radical mastectomy for breast cancer.

Guanine nucleotide exchange factor for eukaryotic initiation factor-2. Cloning of cDNA for the delta-subunit of rabbit translation initiation factor-2B

Peptide sequence data for rabbit eIF-2B delta were obtained and used to design redundant oligonucleotides for PCR. RNA was isolated from rabbit liver and used to direct the synthesis of total cDNA. A rabbit eIF-2B delta transcript was then amplified by PCR and sequenced. The PCR product was used to isolate a clone from a rabbit liver cDNA library. RACE (rapid amplification of cDNA ends) was used to obtain further 5' sequence. Subsequently, a full length cDNA was obtained from a rabbit reticulocyte library. PCR was used to confirm that the sequence is the same for the liver factor. The sequence obtained shows strong homology to that of yeast eIF-2B delta, the GCD2 gene product.

Pituitary-adrenal function in asthmatic patients treated with high dose of beclomethasone

Ten asthmatic patients receiving long term treatment with high dose of inhaled beclomethasone dipropionate (BDP) (750 to 2,250 micrograms/die, average 1,400 +/- 474 micrograms) underwent evaluation of hypothalamic-pituitary-adrenal (HPA) axis under basal conditions (serum cortisol and ACTH levels at 8.00 AM and 8.00 PM, 24-hours free urinary cortisol) and by means of pharmacological tests (short tetracosactide and Corticotrophin Releasing Factor Tests). Basal ACTH serum levels at 8.00 PM were lower than the normal values in all patients: three patients had reduced 24-hr free urinary cortisol and six subjects showed lower cortisol serum levels at 8.00 PM. A normal response to the short tetracosactide test was observed in all patients, whilst Corticotrophin Releasing Factor (CRF) induced an increase in ACTH and cortisol levels (expressed as delta AUC) that was significantly lower in the BPD treated patients compared with a control group of five healthy subjects (p < 0.05). Thus BPD, in high doses, may cause a partial inhibition of HPA axis. Our results show that determination of basal ACTH level and CRF test are more sensitive than serum cortisol levels and short tetracosactide test to evaluate a suppression of HPA axis in patients receiving long term inhaled high doses of BDP.

Effect of deflazacort on growth hormone response to insulin tolerance test

Deflazacort (DF) has been claimed to be provided with a reduced distribution into the central nervous system, therefore it is conceivable that this glucocorticoid holds a lower inhibitory effect on GH secretion. To test this hypothesis we studied the GH response to insulin tolerance test (ITT) in two matched groups of patients given equivalent doses of DF and prednisone (PN). The serum glucose changes induced by ITT were similar in the two groups and in control subjects; the mean increase in plasma GH, in particular the peak and the area under the curve (delta AUC), were not different in control subjects and DF-treated patients (25 +/- 12.5 ng/ml and 1790 +/- 904 ng/ml/min versus 27.7 +/- 21.5 ng/ml and 1578 +/- 1242 ng/ml/min) but were significantly reduced in PN-treated patients (8.8 +/- 9.7 ng/ml and 431.6 +/- 451 ng/ml/min). Our study demonstrates that DF does not interfere with the GH response to ITT as PN does.

[Isolated ACTH deficiency and transient GH deficiency. Presentation of a case]

In a 46 year old man, who arrived at our observation suffering for three months from considerable increasing weakness and progressive impairment of libido, we documented a condition of secondary hypocorticism due to an isolated ACTH deficiency associated with a reduced somatotropin reserve, the last improved after treatment with corticosteroids. We found low serum levels of ACTH and cortisol, good response of adrenal glands to corticotropin depot, normalization of the clinical board during glucocorticoid replacement. Stimulating test with CRH (corticotropin releasing hormone) did not cause a response in ACTH, suggesting the presence of primitive damage of the hypophyseal corticotroph cells.

[Recent findings on the etiopathogenesis of multinodular goiter. II. Thyroid growth factors]

In the last ten years several experimental data have suggested that growth factors may play an important role in modulating thyroid growth and function. Epidermal Growth Factor (EGF) is present in large quantities in thyroid tissue, where it appears to stimulate DNA synthesis and inhibit cellular function. Insulin-like Growth Factors (IGFs), Interleukin I (IL-I) and Fibroblast Growth Factor (FGF) show the same stimulation on cell proliferation. On the contrary Transforming Growth Factor beta (TGF-beta) and somatostatin display inhibitory effects on follicular growth. Therefore it is likely that growth factors' altered production and/or their receptors abnormal expression on the thyroid cells surface might be involved in the development of multinodular goiter and some thyroid neoplasms.

[Recent findings on the etiopathogenesis of multinodular goiter. I. Immunoglobulin stimulation of thyroid growth]

This present review of the literature deals with the possible autoimmune genesis of the multinodular goiter. Some investigators have identified an immunoglobulin stimulating specifically the growth of the thyroid gland (TGI) in the sera of patients affected with sporadic goiter, quite different from TSI, involved in Graves' disease. Other authors report divergent results; however there are many methological differences in these studies that give rise to controversies about the evaluation of the data. At present, these studies have failed to demonstrate consistently an autoimmune genesis of multinodular goiter.

Calcitonin serum levels in different pituitary diseases. A preliminary report

The calcitonin (CT) concentration has been determined in the serum of 17 patients with different pituitary diseases. More or less elevated levels were found in 7 of them. No definite correlation has been observed between the immunoreactive CT and the different pituitary hormones.