Increased gallium-68 DOTATOC uptake in normal thyroid glands.

Increased Ga-68 DOTATOC uptake for normal and goitrous and/or nodular thyroids has previously been reported for a small number of patients. The aim of this study was to reevaluate these preliminary findings with larger patient numbers and to determine possible variables, which might influence the quantification of Ga-68 DOTATOC uptake in normal and pathologic thyroid tissues. Ga-68 DOTATOC PET scans of 165 patients classified for various thyroid pathologies were analyzed by the so-called region of interest technique for Ga-68 DOTATOC uptake and the patient's history, thyroid ultrasound, TSH, and anti-TPO antibodies. Thyroid glands without any pathology showed a clearly detectable uptake of Ga-68 DOTATOC with a large variability and significantly higher target to background ratios for men as compared to women. In 8 cases of normal thyroids with an increased uptake, follow-up examinations after 6-14 months did not show any thyroid pathology. An increased DOTATOC uptake (target to background ratio >3.4) was found in hot nodules, disseminated thyroid autonomy, and in most cases (5 of 8) of active Hashimoto's disease. In Ga-68 DOTATOC PET, normal thyroid glands show a clearly detectable radiotracer uptake with a large variability and significantly higher target to background ratios in male patients. All patients with thyroid autonomy and most patients with active Hashimoto's disease have an increased thyroid DOTATOC uptake.

Myocardial Infarction after Long-Term Treatment with a Tyrosine Kinase Inhibitor (TKI) with Anti-VEGF Receptor Activity.

TKIs including anti-VEGF receptor activity have been approved for the treatment of patients with radioiodine resistant thyroid carcinomas. For lenvatinib arterial thromboembolic events are listed as adverse events of special interest with lenvatinib. In the phase III study, arterial thromboembolic events were reported in 3% of lenvatinib-treated patients and 1% in the placebo group. Most of the patients had predisposing factors. Only one myocardial infarct was reported in the lenvatinib phase III study. We report a 73-year-old female patient with metastatic thyroid papillary carcinoma who was treated with total thyroidectomy. The operation was followed by four radioiodine therapies over a period of 6 years. At 6 years she developed lung metastasis without radioiodine uptake, one solitary liver metastasis and one solitary right renal metastasis. One year after the first diagnosis of radioiodine resistant lung metastasis the lung metastasis showed progression according to RECIST criteria. This treatment was resulting in prolonged partial response with disappearance of a hepatic and renal metastasis. A myocardial infarction occurred after 39 months of lenvatinib treatment resulting in implantation of 3 stents and a two chamber pacemaker. The treatment was discontinued. Except for well controlled hypertension there were neither predisposing diseases like diabetes nor symptoms of cardiac ischemia on exertion. However, the family history for cardiovascular diseases was positive for cardiac infarction reported for one brother. Another brother was treated for hypertension and the patient's mother suffered from a cerebral infarction at the age of 60. While only one myocardial infarct was reported in the lenvatinib phase III study with 392 patients this case suggests that long-term treatment with lenvatinib may be associated with an increased risk for myocardial infarct also in patients with no predisposing diseases except well controlled hypertension and positive family history for cardiovascular diseases.

Visualizing inflammation activity in rheumatoid arthritis with Tc-99 m anti-CD4-mAb fragment scintigraphy.

PURPOSE: T-cell-located CD4 antigen represents one of the therapeutic targets in rheumatoid arthritis (RA). However, up to now there is no established imaging tool to visualize this target in vivo. The aim of our study was to assess the safety and tolerability of a technetium-99m labelled murine anti-human CD4 IgG1-Fab fragment ([(99m)Tc]-anti-CD4-Fab, [(99m)Tc]-EP1645) in patients with active synovitis due to RA, and to evaluate its potential as a marker of disease activity. METHODS: In the present phase I proof of principle study five patients with RA were examined. Planar scans of the whole body, hands, and feet were taken 30 min up to 24h after application of 550 ± 150 MBq [(99m)Tc]-anti-CD4-Fab, followed by visual analyses, comparison with clinical data in 68 joints per patient and semiquantitative analysis of hand and wrist joints. RESULTS: Neither infusion related adverse events nor adverse events during follow up were observed. No increase in human anti-murine antibody titres was seen. All patients had positive scans in almost 70% of clinically affected joints. Positive scans were also found in 8% of joints without evidence of swelling or tenderness. CONCLUSION: Scintigraphy with [(99m)Tc]-anti-CD4-Fab is a promising technique for evaluation of inflammatory activity in patients with RA, pre-therapeutical evaluation of CD4 status and therapy control. Tracer uptake in clinically inconspicuous joints strongly indicates diagnostic potential of [(99m)Tc]-anti-CD4-Fab. Whether this technique is eligible as a prognostic factor in RA needs to be analysed in further studies as well as the pathophysiological background of clinically affected joints lacking tracer uptake.

Ectopic Cushing's syndrome caused by a well differentiated ACTH-secreting neuroendocrine carcinoma of the ileum.

Cushing's syndrome can be caused by adrenocorticotropic hormone-secreting solid tumors. We report a rare case of an ileal endocrine carcinoma that produced ACTH and induced hypercortisolism. A now 47-year-old man presented at age 41 with weight gain, tremor, perspiration, and general fatigue. Laboratory testing showed hypercortisolism and diabetes mellitus. Further examinations revealed ectopic Cushing's syndrome. The search for the primary tumor was difficult. The patient underwent subtotal thyroidectomy and surgical removal of a pituitary lesion. After resection of an ACTH-producing metastasis of the mesentery, temporary remission of Cushing's syndrome ensued. At the age 45 the primary tumor was detected in the ileum by Ga-68 DOTATOC-PET scan and explorative laparotomy. After surgical removal of this well differentiated neuroendocrine carcinoma the patient significantly improved clinically. He experienced better blood pressure and remission of his diabetes mellitus in addition to increased muscular strength. Endocrine laboratory testing at follow-up examinations confirmed remission of hypercortisolism and diabetes mellitus. A Ga-68 DOTATOC PET scan and a 1 mg dexamethasone suppression test 5 months after surgery showed normal results. Ectopic ACTH secretion within the small bowel is very rare. This case underscores the difficulty in locating the source of ectopic ACTH secretion and suggests using small bowel barium study, tubus endoscopy or video endoscopy for preoperative localization if the small bowel is suspected as tumor source.

Correlation of cognitive status, MRI- and SPECT-imaging in CADASIL patients.

Although there is evidence for correlations between disability and magnetic resonance imaging (MRI) total lesion volume in autosomal dominant arteriopathy with subcortical infarcts and leukoencephalopathy (CADASIL), the significance of structural MRI abnormalities for cognitive dysfunction remains controversial. We performed detailed neuropsychological testing, high resolution MRI, and Tc-99m-ethyl cysteinate-dimer SPECT in three CADASIL patients. MR-images were rated independently by two investigators for the presence of white matter lesions, lacunar infarcts, microbleeds, and ventricular enlargement. Cortical atrophy was quantified by the use of automatic morphometric assessment of the cortical thickness. In addition, laboratory and patients' history data were collected in order to assess the individual vascular risk factor profile. The differences in cognitive performance between the three patients are neither explained by structural-, or functional neuroimaging, nor by the patient-specific vascular risk factor profiles. The neuroradiologically least affected patient met criteria for dementia, whereas the most severely affected patient was in the best clinical and cognitive state. Conventional structural and functional neuroimaging is important for the diagnosis of CADASIL, but it is no sufficient surrogate marker for the associated cognitive decline. Detailed neuropsychological assessment seems to be more useful, particularly with respect to the implementation of reliable outcome parameters in possible therapeutic trials.