Abstract: Ectopic production of CRH by a medullary thyroid carcinoma or its metastases is a rare cause of ectopic Cushing's syndrome (ECS). We report a 45-year old male with medullary thyroid carcinoma (MTC), who, 24 years following the initial diagnosis, presented with clinical and biochemical evidence of an ACTH dependent Cushing's syndrome. Rapid deterioration of his clinical condition and elevated cortisol levels were observed. Computed tomographic imaging of the abdomen revealed extensive liver metastases. The patient underwent fine needle aspiration biopsy of a liver lesion and immunohistochemistry showed that the cells expressed calcitonin, carcino-embryonic antigen and synaptophysin. Further analysis revealed that the material also expressed CRH. This is an unusual case of a CRH-secreting liver metastasis from a medullary thyroid carcinoma 24 years after the initial diagnosis of MTC.
Abstract: In recent years, the volume of diagnostic procedures involving the use of ionizing radiation has rapidly increased. Technological advances in computed tomography (CT) equipment, with the availability of multi-slice acquisition and the introduction of hybrid systems, have made this modality extremely popular among other diagnostic procedures, especially in pediatrics and as a screening procedure for asymptomatic adults. Physicians' major radiation-related concern regarding diagnostic imaging, is possible iatrogenic malignancy. According to major national and international organizations responsible for evaluating radiation risks, there is no low-radiation threshold for inducing cancer. This means that no amount of radiation should be considered absolutely safe. Although, the risk of radiation-induced cancer is much smaller than the risk of cancer from natural sources, it can become a public health concern if large numbers of the population undergo increased numbers of CT screening procedures that may even be of uncertain benefit. In order to reduce the overall radiation dose from CT procedures in the population, it is important to keep radiation dose as low as reasonably achievable, by adjusting scanner parameters separately for each individual. In addition, it is crucial to eliminate the inappropriate referrals for CT tests and choose other diagnostic modalities, such as sonography, magnetic resonance imaging systems, or nuclear medicine procedures. While CT remains an important diagnostic procedure, it is important for health care community to reconsider the indications of a CT scan, especially in children and asymptomatic patients. Physicians who prescribe CT could assess its use on a case-by-case basis. When used prudently and optimally, CT remains a very valuable imaging modalitiy for both children and adults.
Abstract: A case of left knee synovitis scintigraphic imaging is presented in a 66-year-old patient with bilateral knee osteoarthritis and a right knee Baker's cyst, who had undergone a 74 MBq (99m)Tc-pertechnetate intra-articular injection in the right knee. The findings in this case were compared with the intravenously injected methylene disphosphonate technetium-99m ((99m)Tc-MDP) scintigraphic findings and could be interpreted as the result of (99m)Tc-pertechenate through blood communication from the right to the left knee. This case implies that (99m)Tc-pertechnetate may be useful in imaging the synovitis in multiple arthroses even up to 60 min after its administration, instead of the 5 min imaging after the injection of (99m)Tc-MDP.
Abstract: Medullary thyroid carcinoma (MTC) as a neuroendocrine tumour arising from C cells of the thyroid gland secrets hormonal peptides; among them, calcitonine (CT) and carcino-embryonic antigen (CEA). These two peptides are used for the diagnosis and treatment response of MTC cases. In patients with advanced MTC, scintigraphy by [(111)In-DTPA-d-phe1]-octreotide is able to detect somatostatin receptors (SSTR) and thus identify regional lymph nodes and/or distal metastases. In this article, we have studied the use of [(111)In-DTPA-d-phe1]-octreotide in the treatment of patients with advanced MTC, and a positive octreotide scan. Twenty-two patients were studied, 16 with persistent MTC and six with relapsed MTC. All patients' tumours were detected by [(111)In-DTPA-d-phe1]-octreotide-scan to be SSTR positive. All patients were treated with the somatostatin analog (SST-A) octreotide, for 3-21 months. Nine patients were treated only with SST-A (Group A). The remaining 13 patients (Group B) received adjuvant treatment as follows: six patients received chemotherapy (Ch), five patients received both Ch and external radiotherapy (eRT) and two patients received only eRT. Results were as follows: Group B patients as compared to Group A patients had about the same objective and biological response. Patients of Group B had relatively better subjective response (less diarrheas and abdominal cramps) versus Group A patients, although this finding was not significant. Group B patients had a longer mean survival time after treatment as compared to Group A patients: 39 months (with a range of 4-72 months) versus 20 months (with a range of 3-60 months) respectively, (P<0.05). Also Group B patients had longer than Group A patients mean total survival time - measured from the start of the disease: 138 (18-270) versus 97 (13-235) months respectively (P<0.05). Based on the above findings, it is the opinion of the authors that patients with advanced MTC and SSTR tumor expression in vivo as indicated by [(111)In-DTPA-d-phe1]-octreotide scanning, when submitted to treatment with SST-A octreotide and adjuvant Ch and/or eRT treatment may have a better treatment response than if submitted to treatment with SST-A octreotide alone. More cases are being studied by us at the present.
Abstract: Our aim was to evaluate right ventricular ejection fraction (RVEF) and left ventricular ejection fraction (LVEF) in patients with chronic pulmonary disease (CPD) during a standard 99mTc-isonitrilium myocardial perfusion study. Forty patients (14 women and 26 men, mean age 67.7 +/- 7 years old) suffering from CPD enrolled in this study. Patients were consecutively submitted to: a) First pass (FP) angiocardiography with 99mTc (Tauc-FP). b) Multigated angiocardiography (MUGA). c) FP with 99mTc-sestamibi (MIBI-FP). d) Gated FP (MIBI-gFP) and GatedSPECT was performed in 23 patients. A simple SPECT study was performed to the rest of them. Our results showed: For the RV: RVEF measured by each method: Tauc-FP =49.09+/-8.4%, MUGA =48.51+/-10.6%, MIBI-FP =49.45+/-7.8 % and MIBI-gFP =52.49+/-6.05%. No difference among these methods was noted (P=0.674). MIBI-FP ejection fraction range was wider than MIBI-gFP and narrower than MUGA. A strong correlation (r=0.88 P<0.01) and good agreement was found between MIBI-gFP and MIBI-FP. Less strong correlation was estimated between not only Tc-FP and MUGA (r=0.76 P<0.01) but MIBI-FP and MUGA (r=0.68 P<0.01) as well with no sufficient agreement. For the LV: LVEF was also measured by each method: Tauc-FP=61,1+/-8,5%, MUGA=61,2+/-10%, MIBI-FP=61,8+/-6%,EF GSPECT=60,2+/-7%. There was a strong correlation (r=0.87 P<0.01) with good agreement between Tauc-FP and MUGA. For all patients, correlation between MIBI-FP and GSPECT was weak (r=0.62 P<0.01) but ameliorated by the exclusion of 4 patients with small end diastolic volumes (EDV) (r=0.82 P<0.01).The correlation between MUGA and GSPECT got stronger (r=0.85 P<0.01) by the same exclusion. Finally, a strong correlation (r=0.81 P<0.01) with sufficient agreement was noted between MIBI-FP and MUGA. IN CONCLUSION: For the RV: simple or gated FP are reliable with good agreement methods of RVEF evaluation in patients with CPD that can easily be performed during every radionuclide isonitrilium myocardial perfusion study. MUGA is proved to be comparative to the FP estimation of RV EF. The gFP affords the narrowest range of RVEF calculated, allowing the more accurate functional identification of RV borders. For the LV: FP (with 99mTc or with sestamibi-99mTc) is a reliable method of LVEF measurement in patients with CPD when compared with MUGA. MuIotaBetaIota-FP can evaluate LVEF during a standard myocardial perfusion study with radionuclide isonitrilium. GSPECT-EF correlation with EF measured by MUGA or FP is strongly affected by EDV.
Abstract: The long-term treatment of metastatic medullary thyroid carcinoma (MTC) with somatostatin (SST) analogs was evaluated in 22 patients with persistant or relapsed disease and with in vivo positive SST receptor (SSTR) tumors. After surgical intervention all patients but one, initially or at a later time, had persistenly (15) or after relapse (7) elevated serum calcitonin (CT, 252-69482 pg/ml) and carcinoembryonic antigen (CEA, 8-1130 ng/ml) concentrations; also, all of them showed positive uptake in 111In-pentetreotide scanning. Daily doses of 0.4-1.0 mg octreotide subcutaneously, or monthly doses of 20-30 mg long-acting octreotide (LAR) intramuscularly for 3-21 months were administered. Systemic chemotherapy (Ch) with or without external radiotherapy (eRT) was given to 13 patients simultaneously. A beneficial effect on pre-existing diarrhea was observed in 8 patients (subjective partial remmission, sPR 36.4%); 10 other patients showed stable disease, while in 4 a worsening of pre-existing diarrhea was observed. CT and CEA concentrations decreased more than 25% in 4 out of 22 patients (18%) and 11 patients showed a decrease of less than 25% (biological SD). No objective response in tumour growth was demonstrated. Patients (10 survivors in group B) treated with Ch+eRT plus Octerotide showed higher sR (92.5%), lower mortality (23.1%), longer mean time to death (130 months) and longer mean total survival (mts) time (145 months) in comparison to group A patients who had 66.7% sR, 33.3% mortality, only 88.5 months mean time to death and 101 months mts-time. Long-term octreotide and octreotide-LAR treatment offers a subjective and biological partial remission in one third and in one fourth of the MTC patients respectively, but it does not improve the natural course of the tumor. It remains to be answered if these drugs, combined with other antineoplastic therapies, have a synergistic effect relating to treatment response and to patient survival and mortality.
Abstract: Left ventricular diastolic filling is a fundamental constituent of cardiac performance. Diastolic function in both adults and children can be routinely assessed by radionuclide ventriculography (RNV). It has previously been shown that factors such as heart rate (HR) and age can significantly modify diastolic performance in adults, thus limiting the clinical applicability of RNV diastolic indices. The aim of this study was to investigate various factors that may affect diastolic function in childhood. Seventy-nine children, aged 40 days to 15 years, were enrolled in the study; their HR ranged from 45 to 160 beats per minute (bpm). All had intact cardiac function and were submitted to baseline RNV prior to chemotherapy initiation for malignancies. Using stepwise linear regression analysis, HR was identified as the major factor affecting RNV diastolic indices during growth. Applying univariate regression models, diastolic indices were corrected for a referrence HR of 100 bpm; this substantially reduced variability of RNV diastolic indices along age increments, allowing for the establishment of reference ranges. In conclusion, HR was shown to be the major determinant of RNV diastolic indices during growth. Adjustment for this variable alone can offer reference ranges for the assessment of left ventricular filling in childhood.
