Effectiveness and toxicity of lenvatinib in refractory thyroid cancer: Dutch real-life data.

OBJECTIVE: The SELECT trial showed progression-free survival (PFS) benefit for lenvatinib for advanced radioiodine-refractory differentiated thyroid cancer (RAI-refractory or RR-DTC) patients, on which current clinical practice is based. We assessed whether the effectiveness and toxicity of lenvatinib in real-life clinical practice in the Netherlands were comparable to the pivotal SELECT trial. METHODS: From three Dutch centres Electronic Health Records (EHRs) of patients treated in the lenvatinib compassionate use program or as standard of care were reviewed and checked for SELECT eligibility criteria. Baseline characteristics, safety, and efficacy measures were compared and PFS and overall survival (OS) were calculated. Furthermore, PFS was compared to estimates of PFS reported in other studies. RESULTS: A total of 39 DTC patients with a median age of 62 years were analysed. Of these, 27 patients (69%) did not fulfil the SELECT eligibility criteria. The most common grade ≥3 toxicities were hypertension (n = 11, 28%), diarrhoea (n = 7, 18%), vomiting (n = 4, 10%), and gallbladder disease (n = 3, 8%). Median PFS and median OS were 9.7 (95% confidence interval (CI): 4.0-15.5) and 18.3 (95% CI: 4.9-31.7) months, respectively, response rate was 38% (95% CI: 23-54%). PFS in the Dutch real-life situation was comparable to previous real-life studies, but inferior to PFS as shown in the SELECT trial (P = 0.04). CONCLUSIONS: PFS in our non-trial population was significantly shorter than in the SELECT trial population. In the interpretation of results, differences in the real-life population and the SELECT study population regarding patient characteristics should be taken into account.

Nationwide study of patients with head and neck paragangliomas carrying SDHB germline mutations.

BACKGROUND: Germline mutations in the succinate dehydrogenase B (SDHB) gene predispose to hereditary paraganglioma (PGL) syndrome type 4. The aim of this study was to evaluate the clinical characteristics and outcome of treatment strategies for patients with head and neck paraganglioma (HNPGL) carrying SDHB germline mutations. METHODS: This was a retrospective evaluation of patients with HNPGL carrying SDHB germline mutations in the Netherlands. RESULTS: In a Dutch nationwide cohort study of SDHB germline mutation carriers, 54 patients with a total of 62 HNPGLs were identified. Forty-one of 54 patients (76 per cent) visited the outpatient clinic because of associated complaints. Eight patients (15 per cent) had multiple PGLs. One patient (2 per cent) developed a phaeochromocytoma and three (6 per cent) developed a malignant PGL. Twenty-seven patients (50 per cent) had an operation for their HNPGL and 15 (28 per cent) received radiotherapy. Three patients with HNPGL (6 per cent) were diagnosed with additional non-paraganglionic tumours. CONCLUSION: If an SDHB germline mutation is identified in a patient with HNPGL, the clinician should be aware of the variable manifestations of the SDHB-linked tumour syndrome, the risk of catecholamine excess, concurrent phaeochromocytoma, and association with non-paraganglionic tumours.

DNA methylation profiling in MEN1-related pancreatic neuroendocrine tumors reveals a potential epigenetic target for treatment.

OBJECTIVE: Epigenetic changes contribute to pancreatic neuroendocrine tumor (PanNET) development. Hypermethylation of promoter DNA as a cause of tumor suppressor gene silencing is a well-established oncogenic mechanism that is potentially reversible and therefore an interesting therapeutic target. Multiple endocrine neoplasia type 1 (MEN1) is the most frequent cause of inherited PanNETs. The aim of this study was to determine promoter methylation profiles in MEN1-related PanNETs. DESIGN AND METHODS: Methylation-specific multiplex ligation-dependent probe amplification was used to assess promoter methylation of 56 tumor suppressor genes in MEN1-related (n = 61) and sporadic (n = 34) PanNETs. Differences in cumulative methylation index (CMI), individual methylation percentages and frequency of promoter hypermethylation between subgroups were analyzed. RESULTS: We found promoter methylation of a large number of potential tumor suppressor genes. CMI (median CMI: 912 vs 876, P = 0.207) was the same in MEN1-related and sporadic PanNETs. We found higher methylation percentages of CASP8 in MEN1-related PanNETs (median: 59% vs 16.5%, P = 0.002). In MEN1-related non-functioning PanNETs, the CMI was higher in larger PanNETs (>2 cm) (median: 969.5 vs 838.5; P = 0.021) and in PanNETs with liver metastases (median: 1036 vs 869; P = 0.013). Hypermethylation of MGMT2 was more frequent in non-functioning PanNETs compared to insulinomas (median: 44.7% vs 8.3%; P = 0.022). Hypermethylation of the Von Hippel-Lindau gene promoter was observed in one MEN1-related PanNET and was associated with loss of protein expression. CONCLUSION: Promoter hypermethylation is a frequent event in MEN1-related and sporadic PanNETs. Targeting DNA methylation could be of therapeutic value in MEN1 patients with advanced PanNETs.

The penetrance of paraganglioma and pheochromocytoma in SDHB germline mutation carriers.

Germline mutations in succinate dehydrogenase B (SDHB) predispose to hereditary paraganglioma (PGL) syndrome type 4. The risk of developing PGL or pheochromocytoma (PHEO) in SDHB mutation carriers is subject of recent debate. In the present nationwide cohort study of SDHB mutation carriers identified by the clinical genetics centers of the Netherlands, we have calculated the penetrance of SDHB associated tumors using a novel maximum likelihood estimator. This estimator addresses ascertainment bias and missing data on pedigree size and structure. A total of 195 SDHB mutation carriers were included, carrying 27 different SDHB mutations. The 2 most prevalent SDHB mutations were Dutch founder mutations: a deletion in exon 3 (31% of mutation carriers) and the c.423+1G>A mutation (24% of mutation carriers). One hundred and twelve carriers (57%) displayed no physical, radiological or biochemical evidence of PGL or PHEO. Fifty-four patients had a head and neck PGL (28%), 4 patients had a PHEO (2%), 26 patients an extra-adrenal PGL (13%). The overall penetrance of SDHB mutations is estimated to be 21% at age 50 and 42% at age 70 when adequately corrected for ascertainment. These estimates are lower than previously reported penetrance estimates of SDHB-linked cohorts. Similar disease risks are found for different SDHB germline mutations as well as for male and female SDHB mutation carriers.

Expression of p27Kip1 and p18Ink4c in human multiple endocrine neoplasia type 1-related pancreatic neuroendocrine tumors.

PURPOSE: Pancreatic neuroendocrine tumors are a major manifestation of multiple endocrine neoplasia type 1 (MEN1). This tumor syndrome is caused by germline mutations in MEN1, encoding menin. Insight into pathogenesis of these tumors might lead to new biomarkers and therapeutic targets for these patients. Several lines of evidence point towards a role for p27Kip1 and p18Ink4c in MEN1-related tumor development in animal models for MEN1, but their contribution to human MEN1-related pancreatic neuroendocrine tumor development is not known. METHODS: In this study, we characterized protein expression of p27Kip1 and p18Ink4c in human MEN1-related PanNETs by immunohistochemistry. From the nationwide DutchMEN1 Study Group database including > 90% of the Dutch MEN1 population, MEN1-patients, who underwent pancreatic surgery, were selected. A tissue micro-array was constructed with available paraffin tissue blocks, and PanNETs from 61 MEN1 patients were eligible for analysis. RESULTS: Expression of p27Kip1 was high in 57 (93%) PanNETs and 67% of the tumors showed low expression of p18Ink4c (67.3%). No association was found between expression of either p27Kip1 or p18Ink4c and clinic-pathological characteristics. CONCLUSIONS: These findings indicate that loss of p18Ink4c, but not p27Kip1, is a common event in the development of MEN1-related PanNETs. Restoration of p18Ink4c function through CDK4/6 inhibitors could be a therapeutic option for MEN1-related PanNETs.

Homozygous TMEM127 mutations in 2 patients with bilateral pheochromocytomas.

Pheochromocytoma (PCC) and paraganglioma (PGL) are rare neuroendocrine tumors that are hereditary in up to 50% of patients. The gene encoding transmembrane-protein-127 (TMEM127) is one of the PCC/PGL-susceptibility genes with an autosomal dominant inheritance pattern. Here, we report 2 patients with bilateral PCC who both harbored a homozygous TMEM127-mutation. In a 31-year-old mentally retarded patient, the homozygous c.410-2A > G mutation was discovered during an update of DNA analysis. A 26-year-old mentally retarded patient was found to have a homozygous c.3G > A mutation. The parents of both patients were consanguineous. We reviewed previously reported clinical features of TMEM127 mutation carriers and compared our findings with case descriptions of homozygous mutations in other PGL/PCC-susceptibility genes. Homozygosity for an autosomal dominant inherited disorder is an extremely rare phenomenon and has, to our knowledge, not been reported before for the gene encoding TMEM127. In the present cases, the clinical picture does not seem to be very different from heterozygous TMEM127 mutation carriers, except for a relatively large tumor size and more pronounced plasma metanephrine concentration. It is unclear whether the mental retardation is causally related to homozygosity of the TMEM127 mutations. Updating genetic screening in patients in whom PCC/PGL has been diagnosed in the past should be considered as it might provide clinically relevant information.

[Diagnostic approach and treatment of primary hyperparathyroidism]. / De diagnostiek en behandeling van primaire hyperparathyreoïdie.

- Primary hyperparathyroidism (PHPT) is characterised by elevated serum calcium levels due to elevated levels, or insufficient suppression, of parathyroid hormone (PTH).- The incidence of PHPT has increased in recent years. This is mainly the result of more frequently performed routine measurements of serum calcium, e.g. as part of postmenopausal screening.- The classically described features of PHPT - bones and stones - are not always observed and most patients are asymptomatic.- Diagnosis of PHPT is only established by biochemical testing, not by imaging.- Ultrasound and technetium-99m sestamibi SPECT-CT are the first-choice imaging modalities. These investigations are necessary to localize the parathyroid adenomas and thereby facilitate minimal invasive parathyroidectomy (MIP).

SDH Subunit Mutation Status in Saliva: Genetic Testing in Patients with Pheochromocytoma.

Germline mutations occur in up to 30-40% of pheochromocytoma/paraganglioma, with mutations in the succinate dehydrogenase (SDH) subunits B (SDHB) and D (SDHD) being the most common. Blood samples are favored for obtaining high quality DNA, however, leukocytes can also be obtained by collecting saliva. The aim of this study was to determine whether SDHB and SDHD gene mutations in patients with pheochromocytoma/paraganglioma could be determined using a salivary sample. Paired blood and salivary samples were collected from 30 patients: 9 SDHB mutation positive, 13 with a SDHD mutation, and 8 without any SDHx mutations. The Oragene DISCOVER kit was used to collect and extract DNA from saliva. Blood DNA was extracted from EDTA blood samples. The DNA purification and concentration were measured by spectrophotometry. The 8 exons of SDHB and the 4 exons of SDHD were amplified and sequenced by PCR-based bidirectional Sanger sequencing. Total DNA yields from blood DNA were similar to those obtained from saliva DNA [mean (±SD) saliva vs. blood DNA concentration 514.6 (±580.8) ng/µl vs. 360.9 (±262.7) ng/µl; p=0.2)]. The purity of the saliva DNA samples was lower than that of blood [mean OD260/OD280 ratio 1.78 (±0.13) vs. 1.87 (±0.04); p=0.001, respectively], indicating more protein contamination in the saliva-extracted DNA. This study shows that salivary DNA collected from patients with pheochromocytoma/paraganglioma is a good alternative for extraction of genomic DNA for its high DNA concentration and acceptable purity and can be used as an alternative to blood derived DNA in screening for SDHB and SDHD mutations.

Therapy of endocrine disease: response and toxicity of small-molecule tyrosine kinase inhibitors in patients with thyroid carcinoma: a systematic review and meta-analysis.

CONTEXT: Many tyrosine kinase inhibitors (TKIs) have been studied in patients with thyroid carcinoma (TC). However, the effect and toxicity of various TKIs in differentiated TC (DTC) and medullary TC (MTC) patients have not been directly compared. The aim of the present systematic review and meta-analysis was to systematically summarize response and toxicity of TKIs in TC patients. METHODS: All major databases were systematically searched for publications on TKIs in TC. Primary endpoint was objective response; secondary endpoints were clinical benefit, percentage TKI dose reduction/discontinuation, hand-foot syndrome, diarrhea, and nausea/vomiting. Meta-analysis was performed using an exact likelihood approach and a logistic regression. Pooled percentages and 95% CIs were reported. RESULTS: In total, 22 publications were included. For DTC patients, gefitinib induced no objective responses. Pooled percentage was highest for pazopanib, 49 (95% CI 33-64)%, and was 17 (95% CI 12-24)% for sorafenib. For MTC, gefitinib and imatinib induced no objective responses, whereas sunitinib induced objective response in 43 (95% CI 14-77)%. For vandetanib and cabozantinib, these numbers were 40 (95% CI 34-46)% and 27 (95% CI 22-32)% respectively. Clinical benefit was found in 53 (95% CI 48-59)% of DTC patients on sorafenib, and in 84 (95% CI 79-88)% and 55 (95% CI 49-61)% of MTC patients on vandetanib and cabozantinib respectively. All TKIs were associated with considerable toxicity. CONCLUSION: The currently studied TKIs show a modest response, while side effects are not negligible. Therefore, we suggest to solely consider TKIs in TC patients with rapid progressive disease, for whom the benefits of treatment outweigh toxicity.

To treat or not to treat: developments in the field of advanced differentiated thyroid cancer.

BACKGROUND: Thyroid cancer is the most prevalent endocrine malignancy. Based on the increased understanding of thyroid tumourigenesis, novel therapeutic agents have been identified. However, given the low incidence, the good prognosis of the majority of these tumours and the limited evidence of different treatment modalities, a wide variety of treatment strategies are available. These are mostly based on small studies, data from retrospective analyses and the particular experiences of treating physicians. We discuss the recent developments in the treatment of advanced differentiated thyroid cancer. CASE DESCRIPTION: Three cases demonstrate the considerations involved in treatment decisions for patients with advanced thyroid cancer. The first patient achieved stable disease for over five years with different targeted therapies. The second patient shows the potential (severe) toxicity of these drugs and the third patient illustrates the indolent nature of this disease. CONCLUSION: The treatment of patients with extensively metastasised thyroid cancer is very complicated. The timing of initiation of therapy and the potential toxicity of targeted therapies are important in the clinical decision to treat or not to treat because of the slowly progressive course of differentiated thyroid cancer. When targeted therapy is considered, it remains of great importance to enrol patients in clinical studies in order to further determine the position of these therapies, to develop more effective (combination) treatment schemes, and above all, to identify those patients that truly benefit.

Intestinal pseudo-obstruction as a complication of paragangliomas: case report and literature review.

Intestinal pseudo-obstruction is a rare and relatively unknown complication of phaeochromocytoma÷ paraganglioma (PCC÷PGL). Its pathophysiology can be explained by the hypersecretion of catecholamines, which may reduce the peristaltic activity of the gastrointestinal tract. Clinically, this can result in chronic constipation, intestinal pseudo-obstruction or even intestinal perforation. We conducted a comprehensive literature search and retrieved 34 cases of pseudo-obstruction caused by either benign or malignant PCC÷PGL. We also included a case from our centre that has not been described earlier. We conclude that intestinal pseudo-obstruction is a rare but potentially life-threatening complication of PCC÷PGL. Intravenous administration of phentolamine is the most frequently described treatment when surgical resection of the PCC÷PGL is not feasible.

The value of detectable thyroglobulin in patients with differentiated thyroid cancer after initial ¹³¹I therapy.

OBJECTIVE: To assess the prognostic value of detectable thyroglobulin (Tg) after initial surgery and radioactive iodine (¹³¹I) therapy by comparing patients with a negative post-therapeutic whole body scan (WBS) with either detectable or undetectable Tg. BACKGROUND: Differentiated thyroid cancer has a good prognosis. However, recurrences can occur up to 30 years after initial treatment. Because life-long follow-up is necessary, it is important to explore possible risk factors associated with recurrence and mortality. DESIGN, PATIENTS AND MEASUREMENTS: We studied 539 patients who were treated between 1980 and 2007. After the last therapeutic dosage of 5550 MBq ¹³¹I, 72 patients had negative post-therapeutic WBS and positive Tg levels (Tg+ group) and 399 patients had negative post-therapeutic WBS and negative Tg (Tg- group). The 68 remaining patients had proven residual macroscopic disease. We investigated recurrences and overall mortality in the Tg+ and Tg- group compared with the Dutch population. RESULTS: In the Tg+ group, detectable recurrences occurred significantly earlier and more frequently than in the Tg- group (19%vs 13%, P = 0·024). Survival between these groups was comparable, but shorter than the general Dutch population [Standardised Mortality Rate (SMR) 1·38 (95% CI 1·12;1·63) (P = 0·003)]. Disease-free survival in the Tg groups was comparable and not significantly different from the Dutch population [SMR = 1·09 (95% CI 0·81;1·34) (P = 0·569)]. CONCLUSION: Patients with detectable Tg during the last ¹³¹I treatment and a negative post-therapeutic WBS have significant earlier and more recurrences than patients without detectable Tg. Survival in both groups is comparable. After initial therapy, the combination of a negative high dose post-therapeutic WBS with detectable Tg is a valuable predictor for earlier and more recurrences, but is not associated with survival.

Preoperative pharmacological management of phaeochromocytoma.

Phaeochromocytoma is a rare catecholamine-secreting neuroendocrine tumour with a high cardiovascular morbidity and mortality if left untreated. Surgical resection is the only curative therapy. During surgery there is a high risk of massive release of catecholamines, which can result in potentially fatal hypertensive crises and cardiac arrhythmias. Administration of vasoactive drugs such as (non)selective alpha- and beta-antagonists and calcium channel blocking agents have reduced the operation risk. Guidelines for the preoperative medical management of the patient with a phaeochromocytoma are mainly based on retrospective studies and case reports. We reviewed the relevant literature on this subject. In addition, we compared the several preoperative treatment protocols of the eight university medical centres in the Netherlands.

[Relatively poor regulation of blood pressure in patients with type-2 diabetes mellitus in the primary care setting and specialists' practice in the Netherlands]. / Matige bloeddrukregulatie bij patiënten met diabetes mellitus type 2 in de eerste en tweede lijn.

OBJECTIVE: To investigate the degree to which the goals for adequate blood-pressure control in patients with type-2 diabetes mellitus (DM) are met in Dutch specialists' practice and in the primary-care setting. DESIGN: Cross sectional. METHOD: Data were collected from all consecutive patients with DM type 2 visiting the outpatient clinic of two physicians specialised in diabetes care, in Zwolle, the Netherlands, in the period 1 November 1999-30 April 2000. The target value for blood pressure was < or = 150/85 mmHg. In addition, baseline data were collected on patients in the primary-care setting who participated in a transmural project in Zwolle in the period 1 February 1997-31 January 1998. In 1998, the target blood pressure in the primary-care setting was < or = 160/90 mmHg. Patients who met the goals for adequate blood-pressure control were compared with patients who did not. RESULTS: A total of 502 patients from specialists' practice and 1084 patients from the primary-care setting were included. The prevalence of hypertension in specialists' practice was 89% (n = 377); of these patients, 140 (37%) had a good regulation of their blood pressure. The patients who had an adequate blood-pressure control and those who did not were comparable. Both groups were prescribed an average of 2.2 kinds of antihypertensive agent per patient. The prevalence of hypertension in the primary care was 69% (n = 733). The goal for adequate blood-pressure control, i.e. a blood pressure of < or = 160/90 mmHg, was achieved in 44% (n = 324). In the primary-care setting, an average of 1.1 kinds of antihypertensive agent was prescribed, 1.6 in patients who achieved the target value and 0.8 in those who did not (p < 0.05). CONCLUSION: Regulation of blood pressure in patients with type 2 DM and hypertension was far from optimal: 37% of patients in specialists' practice and 44% of those in the primary-care setting achieved the target values.