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15 result(s) for "Franssen, Gaston J."
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Peptide receptor radionuclide therapy in patients with medullary thyroid carcinoma: predictors and pitfalls
Background For progressive metastatic medullary thyroid carcinoma (MTC), the available treatment options with tyrosine kinase inhibitors result in grade 3–4 adverse events in a large number of patients. Peptide Receptor Radionuclide Therapy (PRRT), which has also been suggested to be a useful treatment for MTC, is usually well tolerated, but evidence on its effectivity is very limited. Methods Retrospective evaluation of treatment effects of PRRT in a highly selected group of MTC patients, with progressive disease or refractory symptoms. In addition, a retrospective evaluation of uptake on historical 111 In-DTPA-octreotide scans was performed in patients with detectable tumor size > 1 cm. Results Over the last 17 years, 10 MTC patients were treated with PRRT. Four out of 10 patients showed stable disease at first follow-up (8 months after start of therapy) whereas the other 6 were progressive. Patients with stable disease were characterized by a combination of both a high uptake on 111 In-DTPA-octreotide scan (uptake grade ≥ 3) and a positive somatostatin receptor type 2a (SSTR2a) expression of the tumor by immunohistochemistry. Retrospective evaluation of historical 111 In-DTPA-octreotide scans of 35 non-treated MTC patients revealed low uptake (uptake grade 1) in the vast majority of patients 31/35 (89%) with intermediate uptake (uptake grade 2) in the remaining 4/35 (11%). Conclusions PRRT using 177 Lu-octreotate could be considered as a treatment in those patients with high uptake on 111 In-DTPA-octreotide scan (uptake grade 3) and positive SSTR2a expression in tumor histology. Since this high uptake was present in a very limited number of patients, this treatment is only suitable in a selected group of MTC patients.
Outcomes after adrenalectomy in elderly patients; a propensity score matched analysis
Adrenal masses are being found more and more often over the years. Given the association of these masses with advancing age, the decision to perform surgery in older, sometimes asymptomatic patients presents a clinical dilemma. These patients are potentially more vulnerable to adverse postoperative outcomes due to increased frailty. Therefore, this study aimed to compare the postoperative course after adrenalectomy in patients aged 70 years and older to that of a younger cohort. This single center retrospective study included patients aged ≥ 70 years who underwent adrenalectomy between 2000–2020, and propensity-score matched younger patients (< 70 years). Patients were matched based on hormonal overproduction, malignant diagnosis, surgical approach and year of surgery. The study included 77 elderly patients (median age 74 years) and 77 younger patients (median age 52 years; p < 0.001). Serious complications (Clavien–Dindo ≥ 3) occurred in 9.1% of elderly patients and 6.5% of the matched younger cohort (p = 0.773). The overall complication rate was 44.2% in elderly and 40.3% in younger patients (p = 0.771), with similar duration of hospital admission and mortality in both groups. Elderly patients experienced mostly infectious (33.8%) or cardiovascular complications (27.0%), and cardiovascular complications were more frequent in elderly than in younger patients (6.7%, p = 0.039). In conclusion, patients aged 70 years and older who undergo adrenalectomy have a similar postoperative course and complication rate as younger patients, with most postoperative complications being minor, and mortality being minimal. Therefore, older age itself should not be a reason to refrain from adrenalectomy.
Serum microRNA profiles in athyroid patients on and off levothyroxine therapy
Levothyroxine replacement treatment in hypothyroidism is unable to restore physiological thyroxine and triiodothyronine concentrations in serum and tissues completely. Normal serum thyroid stimulating hormone (TSH) concentrations reflect only pituitary euthyroidism and, therefore, novel biomarkers representing tissue-specific thyroid state are needed. MicroRNAs (miRNAs), small non-coding regulatory RNAs, exhibit tissue-specific expression patterns and can be detectable in serum. Previous studies have demonstrated differential expression of (precursors of) miRNAs in tissues under the influence of thyroid hormone. To study if serum miRNA profiles are changed in different thyroid states. We studied 13 athyroid patients (6 males) during TSH suppressive therapy and after 4 weeks of thyroid hormone withdrawal. A magnetic bead capture system was used to isolate 384 defined miRNAs from serum. Subsequently, the TaqMan Array Card 3.0 platform was used for profiling after individual target amplification. Mean age of the subjects was 44.0 years (range 20-61 years). Median TSH levels were 88.9 mU/l during levothyroxine withdrawal and 0.006 mU/l during LT4 treatment with a median dosage of 2.1 μg/kg. After normalization to allow inter-sample analysis, a paired analysis did not demonstrate a significant difference in expression of any of the 384 miRNAs analyzed on and off LT4 treatment. Although we previously showed an up-regulation of pri-miRNAs 133b and 206 in hypothyroid state in skeletal muscle, the present study does not supply evidence that thyroid state also affects serum miRNAs in humans.
Levoketoconazole, the 2S,4R Enantiomer of Ketoconazole, a New Steroidogenesis Inhibitor for Cushing’s Syndrome Treatment
Abstract Introduction Racemic ketoconazole (RK) is a steroidogenesis inhibitor used for treatment of Cushing’s syndrome. Levoketoconazole (COR-003), the pure 2S,4R enantiomer, is potentially more potent and safe compared to RK. We compared in vitro effects of levoketoconazole and RK on adrenocortical and pituitary adenoma cells. Materials and methods HAC15 cells and 15 primary human neoplastic adrenocortical cultures (+/− ACTH), and murine (AtT20) and human corticotroph adenoma cultures were incubated with levoketoconazole or RK (0.01-10 µM). Cortisol and ACTH were measured using a chemiluminescence immunoassay system, and steroid profiles by liquid chromatography-tandem mass spectrometry (LC-MS/MS). Results In HAC15, levoketoconazole inhibited cortisol at lower concentrations (IC50: 0.300 µM) compared to RK (0.611 µM; P < 0.0001). IC50 values of levoketoconazole for basal cortisol production in primary adrenocortical cultures varied over a 24-fold range (0.00578-0.140 µM), with 2 patients having a higher sensitivity for levoketoconazole vs RK (2.1- and 3.7-fold). LC-MS/MS analysis in selected cases revealed more potent inhibition of cortisol and other steroid profile components by levoketoconazole vs RK. In AtT20, levoketoconazole inhibited cell growth and ACTH secretion (10 µM: −54% and −38%, respectively), and levoketoconazole inhibited cell number in 1 of 2 primary human corticotroph pituitary adenoma cultures (−44%, P < 0.001). Conclusion Levoketoconazole potently inhibits cortisol production in adrenocortical cells, with a variable degree of suppression between specimens. Levoketoconazole inhibits adrenal steroid production more potently compared to RK and might also inhibit ACTH secretion and growth of pituitary adenoma cells. Together with previously reported potential advantages, this indicates that levoketoconazole is a promising novel pharmacotherapy for Cushing’s syndrome.
The Efficacy of Mitotane in Human Primary Adrenocortical Carcinoma Cultures
Abstract Context Patients with adrenocortical carcinoma (ACC) often fail mitotane treatment and deal with severe toxicity, marking the relevance of predictive parameters for treatment outcome. Objective Determine the effects of mitotane in primary ACC cultures, and correlate sensitivity with patient and tumor characteristics. Methods In 32 primary ACC cultures, the effects of mitotane on cell growth and cortisol production were determined. RRM1, SOAT1, and CYP2W1 expression were assessed using reverse transcription-polymerase chain reaction and immunohistochemistry. Results The median percentage cell amount inhibition in primary ACC cultures at 50 µM mitotane was 57%. Seven patients were classified as nonresponders, 14 as partial responders, and 11 as responders. The mean median effective concentration (EC50) value of mitotane for inhibition of cell amount in responders was 14.2 µM (95% CI, 11.3–17.9), in partial responders 41.6 µM (95% CI, 33.5–51.8), and could not be calculated in nonresponders. The percentage cortisol-producing ACC was 14%, 43%, and 73% for nonresponders, partial responders, and responders (P = 0.068). Mitotane inhibited cortisol production with a mean EC50 of 1.4 µM (95% CI, 0.9–2.1), which was considerably lower than the EC50 on cell growth. RRM1, SOAT1, and CYP2W1 expression levels were not predictive for mitotane sensitivity in vitro. Conclusion Direct antitumor effects of mitotane on human primary ACC cultures are highly variable between patients, reflecting heterogeneous responses in patients. Cortisol was inhibited at lower concentrations, compared with its effect on cell amount. Cortisol secretion by ACC might be associated with enhanced mitotane sensitivity due to increased direct antitumor effects of mitotane.
Evolution of the Mesenteric Mass in Small Intestinal Neuroendocrine Tumours
Background: A metastatic mesenteric mass is a hallmark of small intestinal neuroendocrine tumours (SI-NETs). However, little is known on its development over time. Therefore, we conducted a study to assess the evolution of a SI-NET-associated mesenteric mass over time. Methods: Retrospectively, 530 patients with proven SI-NET were included. The presence and growth of a mesenteric mass was assessed using RECIST 1.1 criteria on every consecutive CT-scan until the end of follow-up or resection. Results: At baseline, a mesenteric mass was present in 64% of the patients, of whom 13.5% showed growth of the mesenteric mass with a median time to growth of 40 months. Male gender was the only independent predictor of growth (OR 2.67). Of the patients without a mesenteric mass at the first evaluation, 2.6% developed a pathological mesenteric mass. Treatment with peptide receptor radionuclide therapy (PRRT; N = 132) resulted in an objective size reduction of the mesenteric mass in 3.8%. Conclusion: The metastatic mesenteric mass in SI-NETs has a static behavior over time. Therefore, site-specific growth behavior should be taken into account when selecting target lesions and assessing disease progression and therapeutic response. PRRT appears not to be effective for size reduction of the mesenteric mass.
Osilodrostat Is a Potential Novel Steroidogenesis Inhibitor for the Treatment of Cushing Syndrome: An In Vitro Study
Abstract Context Metyrapone and ketoconazole, frequently used steroidogenesis inhibitors for treatment of Cushing syndrome, can be associated with side effects and limited efficacy. Osilodrostat is a CYP11B1 and CYP11B2 inhibitor, with unknown effects on other steroidogenic enzymes. Objective To compare the effects of osilodrostat, metyrapone, and ketoconazole on adrenal steroidogenesis, and pituitary adenoma cells in vitro. Methods HAC15 cells, 17 primary human adrenocortical cell cultures, and pituitary adenoma cells were incubated with osilodrostat, metyrapone, or ketoconazole (0.01 to 10 µM). Cortisol and ACTH were measured using chemiluminescence immunoassays, and steroid profiles by liquid chromatography-mass spectrometry. Results In HAC15 cells, osilodrostat inhibited cortisol production more potently (IC50: 0.035 µM) than metyrapone (0.068 µM; P < 0.0001), and ketoconazole (0.621 µM; P < 0.0001). IC50 values of osilodrostat and metyrapone for basal cortisol production varied with a 25- and 18-fold difference, respectively, with comparable potency. Aldosterone production was inhibited more potently by osilodrostat vs metyrapone and ketoconazole. Osilodrostat and metyrapone treatment resulted in strong inhibition of corticosterone and cortisol, 11-deoxycortisol accumulation, and modest effects on adrenal androgens. No pituitary-directed effects of osilodrostat were observed. Conclusions Under our study conditions, osilodrostat is a potent cortisol production inhibitor in human adrenocortical cells, comparable with metyrapone. All steroidogenesis inhibitors showed large variability in sensitivity between primary adrenocortical cultures. Osilodrostat might inhibit CYP11B1 and CYP11B2, in some conditions to a lesser extent CYP17A1 activity, and a proximal step in the steroidogenesis. Osilodrostat is a promising treatment option for Cushing syndrome, and in vivo differences with metyrapone are potentially driven by pharmacokinetic differences. The in vitro effects of osilodrostat on human adrenal steroidogenesis are studied compared with metyrapone and ketoconazole. We show that it is a promising novel treatment of Cushing syndrome.
Outcomes after Surgical Treatment of Metastatic Disease in the Adrenal Gland; Valuable for the Patient?
The adrenal glands are common dissemination sites for metastasis of various solid tumors. Surgical treatment is often recommended because targeted therapies and immunotherapy are frequently ineffective for adrenal metastasis. We report the experience with short-term and long-term surgical outcomes of patients undergoing surgery for adrenal metastasis in two hospitals. A retrospective, multicenter study was performed to analyze patient characteristics, tumor-related data, perioperative outcomes, and oncological outcomes. Postoperative complications that occurred within 30 days were scored according to the Clavien Dindo classification. Metastatic adrenalectomy was performed in 95 patients. We observed an increase from an average of 3 metastatic adrenalectomies per year between 2001–2005 to 10 between 2015–2019. The most frequent underlying malignancies were colorectal and lung cancer. In 55.8%, minimal invasive adrenalectomy was performed, including six conversions to open surgery. A total of 37.9% of patients had postoperative complications, of which ileus or gastroparesis, wound problems, pneumonia, and heart arrhythmias were the most occurring complications. Improved cancer care has led to an increased demand for metastatic adrenalectomy over the past years. Complication rates of 37.9% are significant and cannot be neglected. Therefore, multidisciplinary teams should weigh the decision to perform metastatic adrenalectomy for each patient individually, taking into account the drawbacks of the described morbidity versus the potential benefits.
Expression of Contactin 4 Is Associated With Malignant Behavior in Pheochromocytomas and Paragangliomas
Pheochromocytomas and paragangliomas (PPGLs) are rare neuroendocrine, usually benign, tumors. Currently, the only reliable criterion of malignancy is the presence of metastases. The aim of this study was to identify genes associated with malignancy in PPGLs. Transcriptomic profiling was performed on 40 benign and 11 malignant PPGLs. Genes showing a significantly different expression between benign and malignant PPGLs with a ratio ≥4 were confirmed and tested in an independent series by quantitative real-time polymerase chain reaction (qRT-PCR). Immunohistochemistry was performed for the validated genes on 109 benign and 32 malignant PPGLs. Functional assays were performed with hPheo1 cells. This study was conducted at the Department of Pathology of the Erasmus MC University Medical Center Rotterdam Human Molecular Genetics laboratory of the de Duve Institute, University of Louvain. PPGL samples from 179 patients, diagnosed between 1972 and 2015, were included. Associations between gene expression and malignancy were tested using supervised clustering approaches. Ten differentially expressed genes were selected based on messenger RNA (mRNA) expression array data. Contactin 4 (CNTN4) was overexpressed in malignant vs benign tumors [4.62-fold; false discovery rate (FDR), 0.001]. Overexpression at the mRNA level was confirmed using qRT-PCR (2.90-fold, P = 0.02; validation set: 4.26-fold, P = 0.005). Consistent findings were obtained in The Cancer Genome Atlas cohort (2.7-fold; FDR, 0.02). CNTN4 protein was more frequently expressed in malignant than in benign PPGLs by immunohistochemistry (58% vs 17%; P = 0.002). Survival after 7 days of culture under starvation conditions was significantly enhanced in hPheo1 cells transfected with CNTN4 complementary DNA. CNTN4 expression is consistently associated with malignant behavior in PPGLs.
Subacute haematotoxicity after PRRT with (177)Lu-DOTA-octreotate: prognostic factors, incidence and course
In peptide receptor radionuclide therapy (PRRT), the bone marrow (BM) is one of the dose-limiting organs. The accepted dose limit for BM is 2 Gy, adopted from (131)I treatment. We investigated the incidence and duration of haematological toxicity and its risk factors in patients treated with PRRT with (177)Lu-DOTA(0)-Tyr(3)-octreotate ((177)Lu-DOTATATE). Also, absorbed BM dose estimates were evaluated and compared with the accepted 2 Gy dose limit. The incidence and duration of grade 3 or 4 haematological toxicity (according to CTCAE v3.0) and risk factors were analysed. Mean BM dose per unit (gigabecquerels) of administered radioactivity was calculated and the correlations between doses to the BM and haematological risk factors were determined. Haematological toxicity (grade 3/4) occurred in 34 (11 %) of 320 patients. In 15 of the 34 patients, this lasted more than 6 months or blood transfusions were required. Risk factors significantly associated with haematological toxicity were: poor renal function, white blood cell (WBC) count <4.0 × 10(9)/l, age over 70 years, extensive tumour mass and high tumour uptake on the OctreoScan. Previous chemotherapy was not associated. The mean BM dose per administered activity in 23 evaluable patients was 67 ± 7 mGy/GBq, resulting in a mean BM dose of 2 Gy in patients who received four cycles of 7.4 GBq (177)Lu-DOTATATE. Significant correlations between (cumulative) BM dose and platelet and WBC counts were found in a selected group of patients. The incidence of subacute haematological toxicity after PRRT with (177)Lu-DOTATATE is acceptable (11 %). Patients with impaired renal function, low WBC count, extensive tumour mass, high tumour uptake on the OctreoScan and/or advanced age are more likely to develop grade 3/4 haematological toxicity. The BM dose limit of 2 Gy, adopted from (131)I, seems not to be valid for PRRT with (177)Lu-DOTATATE.