Metastasising ameloblastoma or ameloblastic carcinoma? A case report with mutation analyses.

BACKGROUND: Ameloblastic carcinoma and metastasising ameloblastoma are rare epithelial odontogenic tumours with aggressive features. Distinguishing between these two lesions is often clinically difficult but necessary to predict tumour behaviour or to plan future therapy. Here, we provide a brief review of the literature available on these two types of lesions and present a new case report of a young man with an ameloblastoma displaying metastatic features. We also use this case to illustrate the similarities and differences between these two types of tumours and the difficulties of their differential diagnosis. CASE PRESENTATION: Our histopathological analyses uncovered a metastasising tumour with features of ameloblastic carcinoma, which developed from the ameloblastoma. We profiled the gene expression of Wnt pathway members in ameloblastoma sample of this patient, because multiple molecules of this pathway are involved in the establishing of cell polarity, cell migration or for epithelial-mesenchymal transition during tumour metastasis to evaluate features of tumor behaviour. Indeed, we found upregulation of several cell migration-related genes in our patient. Moreover, we uncovered somatic mutation BRAF p.V600E with known pathological role in cancerogenesis and germline heterozygous FANCA p.S858R mutation, whose interpretation in this context has not been discussed yet. CONCLUSIONS: In conclusion, we have uncovered a unique case of ameloblastic carcinoma associated with an alteration of Wnt signalling and the presence of BRAF mutation. Development of harmful state of our patient might be also supported by the germline mutation in one FANCA allele, however this has to be confirmed by further analyses.

Lymphoscintigraphy of the Lower Extremities: Discrepancies Between Superficial and Deep Lymphatic Systems.

ABSTRACT: We describe a 57-year-old man with prostate cancer. A radical prostatectomy with a pelvic lymphadenectomy was performed. After 2 years, a mild swelling of the lower extremities appeared, and the patient was referred for lower-limb lymphoscintigraphy. A lymphoscintigraphy of the superficial lymphatic system in the limbs showed prominent, dermal backflow in the area of the right hypogastrium. Lymphoscintigraphy of the deep lymphatic system showed reflux in the left hypogastrium. This discrepancy between the findings in the superficial and deep lower-limb lymphatic systems was explained by asymmetric sampling of the lymph nodes during the lymphadenectomy.

Combination of myocardial perfusion imaging, left ventricle function parameters and coronary artery calcium score in risk evaluation in patients with diabetes mellitus.

OBJECTIVE: Myocardial perfusion imaging (MPI) can be challenging in some cases of multi vessel involvement. Our aim was to examine specific group of patients with diabetes mellitus (DM), who did not have significant reversible ischaemia diagnosed on perfusion study itself, and asses additional value of functional parameters obtained from gated acquisition and added information from coronary artery calcium score (CACS). SUBJECTS AND METHODS: One hundred and seventy eight patients with a history of DM, with summed difference score (SDS)≤1, were included in the study. All patients underwent gated acquisition with recording of functional parameters and CACS evaluation. During the follow-up, cardiac events (CE) were recorded. RESULTS: During the median follow-up of 20.3 months there were 23 CE encountered. Optimal cut-off value for CACS to predict CE was found at 1427, higher values were significantly related to CE (P<0.001). Low stress left ventricular ejection fraction (LVEF) <45% and induced stress LVEF drop for 5% were also more frequent in CE group (P=0.001, P=0.008). Multivariable Cox analysis revealed low stress LVEF (P=0.001, HR=4.48, 95%CI 1.79-11.22), stress induced LVEF drop (P=0.017, HR 3.13, 95%CI 1.22-8.01) and high CACS (P<0.001, HR 10.52, 95%CI 4.32-25.63) as significant predictors of CE. CONCLUSION: Low stress LVEF under 45%, post-stress LVEF drop for more than 5% and CACS more than or equal to 1427 are significant predictors of CE in patients with DM, who did not have reversible ischemia detected on MPI single photon emission computed tomography (SPECT).

Quantitative analysis in parathyroid adenoma scintigraphy.

OBJECTIVE: Surgery is the only curative treatment for primary hyperparathyroidism. Parathyroid scintigraphy is one method used to preoperatively localize the lesion. We examined time-related changes in radiopharmaceutical uptake in parathyroid adenomas (PTAs) and thyroid gland by quantitative single-photon-emission computed tomography (SPECT) imaging to assess differences between rapid and delayed washout patterns. PATIENTS AND METHODS: The study group consisted of 35 histologically verified PTAs after radio-guided surgery extirpation in 33 patients with primary hyperparathyroidism. Patients underwent a three-phase SPECT/CT study of the neck and upper thorax post 99mTc-methoxyisobutylisonitrile (MIBI) injection. Images were reconstructed using a proprietary ordered-subset-conjugate-gradient-maximization algorithm (Siemens xSPECT Quant). PTAs were divided into those with a rapid (group A) and those with a slow (group B) washout pattern. SUVmax values of PTAs and thyroid gland tissue at 10, 90 and 180 min post 99mTc-MIBI injection were recorded and statistically assessed. Retention indexes related to the early examination were calculated for PTA and thyroid gland (RI-PTA and RI-TG). RESULTS: There were 11 PTAs in group A and 24 in group B. Significant between-group differences in PTA SUVmax and PTA/thyroid gland ratios were observed only at 180 min postinjection (P = 0.0297, P = 0.0222, respectively). RI-PTAs differed significantly at 90 and 180 min postinjection (P = 0.0298, P = 0.0431). No differences in PTA volumes, thyroid gland SUVmax values or RI-TG were observed between the groups. CONCLUSION: PTAs with rapid and slow washout patterns have different characteristics on quantitative analysis in later phases. No significant differences in directly measurable quantitative values (SUVmax, PTA/thyroid gland ratio) at the early stages of multi-phase examination were observed.

Individualised Timing of Radio-Guided Parathyroidectomy Using Multi-Phase SPECT/CT Increases In Vivo Sensitivity and Accuracy and Reduces Operating Time: A Randomised Clinical Trial.

Background: Minimally invasive parathyroidectomy is the preferred treatment for primary hyperparathyroidism. Despite relatively accurate preoperative information, minimally invasive parathyroidectomy can be challenging, especially in the case of small and ectopic adenomas. Radio guidance aids in both in vivo identification and ex vivo confirmation of adenoma. In vivo accuracy is currently not satisfactory. The present study evaluated whether a beneficial effect (increased sensitivity, specificity, accuracy) is obtained with individualised timing of minimally invasive radio-guided parathyroidectomy (MIRGP) using preoperative multi-phase 99mTc-MIBI single photon emission computed tomography (SPECT)/computed tomography (CT). Methods: This randomised clinical trial was conducted from May 2016 to January 2020 in a tertiary referral hospital. Adult patients with primary hyperparathyroidism sent for 99mTc-MIBI SPECT/CT were included consecutively and randomly assigned to conventional (dual-phase) SPECT/CT and conventional MIRGP (group I) or multi-phase SPECT/CT and individualised MIRGP (group II). One hundred of 106 eligible patients were included, and 83 patients underwent complete intervention. Results: A total of 47 patients in group I and 35 patients in group II were analysed. Group II had a shorter operating time (p = 0.003). The in vivo sensitivity and accuracy of radio guidance was 85.1% in group I and 100% in group II (p = 0.046), and 90.4% in group I and 100% in group II (p = 0.021), respectively. We found no difference in the in vivo specificity and ex vivo parameters between groups. Conclusion: Individualised timing increased the in vivo sensitivity and accuracy of radio guidance and reduced operating time, as some parathyroid adenomas rapidly wash out the radionuclide.

Osteolytic bone lesions, hypercalcemia and paraprotein, but not a myeloma: case report and review of literature.

In June 2018, 77-year-old man was referred to The Department of Haematooncology, University Hospital Ostrava, for suspicion of multiple myeloma. This was supported by laboratory findings of hypercalcemia, paraprotein IgA κ in serum and by the presence of multiple osteolytic skeletal lesions. Low number of plasma cells in bone marrow sample - cytologically (3.6 %) as well as in flow cytometry (less than 95 % clonal plasma cells out of total bone marrow plasma cells) - pointed at the direction of monoclonal gammopathy of undetermined significance (MGUS). In the course of differential diagnosis of hypercalcemia, elevated level of parathormone had been found which led to the performance of 99mTc-MIBI scintigraphy where parathyroid adenoma was discovered and later histologically verified. The final diagnosis was determined as a coincidence of MGUS and primary hyperparathyroidism. This case report also contains brief differential diagnosis of hypercalcemia and osteolytic skeletal lesions and suggestions for their diagnostic algorithms.

Additional value of the coronary artery calcium score in patients for whom myocardial perfusion imaging is challenging.

BACKGROUND Determination of prognosis based on ischemia detection, using single­photon emission computed tomography myocardial perfusion imaging (SPECT­MPI), can be challenging in patients with multiple affected coronary arteries. AIMS The aim of the study was to examine the outcomes of SPECT­MPI combined with the coronary artery calcium score (CACS) to identify predictors of adverse cardiac events (ACEs) in patients for whom ischemia detection may be difficult using SPECT­MPI. METHODS The study group included 195 patients with a history of chronic kidney disease, suspected ischemic cardiomyopathy, or left bundle branch block. All patients underwent SPECT­MPI and CACS evaluation. During the follow­up, ACEs were recorded. Perfusion and functional parameters as well as the CACS were analyzed to find the predictors of ACEs. RESULTS The ACEs were recorded in 58 individuals (29.7%) and were significantly associated with ischemia (P <0.001), abnormal functional parameters (P = 0.04), and higher CACSs (P <0.001). The optimal cutoff value of the CACS to predict an ACE was 530. Cox proportional hazards models revealed that age, mild and severe ischemia, functional abnormalities, and a CACS of 530 or higher were significant predictors of ACEs. In the subgroup of individuals without ischemia, a CACS of 530 or higher was significantly associated with poor outcome, while we recorded only 3 ACEs in these patients when the CACS was lower than 530. CONCLUSIONS The addition of the CACS to SPECT­MPI improves the identification of patients at higher risk for ACEs, even in individuals for whom SPECT­MPI is challenging.

Feasibility of ultra low-dose thallium stress-redistribution protocol including prone imaging in obese patients using CZT camera.

High efficiency cadmium-zinc-telluride (CZT) cameras provide an opportunity to lower the injected activities of radiopharmaceuticals for single photon emission tomography (SPECT) myocardial perfusion imaging (MPI). The limits for reducing activities of thallium have not been determined, particularly in obese patients. After an injection of 0.7 megabecquerel (MBq) of thallium/kg, we collected an average 1.5 million counts for the 10-min acquisition in a pilot cohort of ten patients. After extrapolation, we reduced the administered activity to 0.5 MBq/kg to obtain the expected 1 million counts. We studied the image quality in 124 patients (86 men, 43 obese with body mass index over 30 kg/m2) referred for MPI. The quality of images was assessed by a number of recorded counts and visually by a four-grade scale (one-poor quality, four-excellent quality). In non-obese and obese patients, the average number of recorded counts was 1.1 vs. 1.07 million counts for the 10-min stress acquisition, 1.04 vs. 1.06 million counts for the 13-min rest acquisition, and the average quality score was 3.97 vs. 3.90, respectively (p = NS).The mean administered activity was 39.2 ± 7 MBq for non-obese and 48.7 ± 6 for obese patients (p < 0.0001), and the calculated effective dose was 4.0 ± 0.7 and 4.9 ± 0.6 mSv respectively (p < 0.0001). The ultra-low-dose thallium stress-redistribution protocol, including post-stress prone imaging, provides good quality of images with a low radiation burden, even in obese patients.

Prognostic value of myocardial perfusion imaging and coronary artery calcium measurements in patients with end-stage renal disease.

OBJECTIVE: Coronary artery disease (CAD) is highly prevalent in patients with end-stage renal disease (ESRD), owing to clustering of traditional and uremic-specific risk factors. However, in this population asymptomatic course of CAD is common and it has been reported that myocardial perfusion imaging (MPI) with single-photon emission tomography (SPET) has lower sensitivity. In the current study, we assessed the value of MPI gated-SPET and its combination with coronary artery calcium (CAC) score measurements in risk stratification of ESRD patients. MATERIALS AND METHODS: MPI gated-SPET was performed with dual-headed SPET camera and CAC score measured by multi-detector computed tomography (MDCT) system.There were tested 77 ESRD individuals. During the follow-up study, cardiac events (CE) defined as cardiac death or nonfatal myocardial infarction (MI) or the necessity for coronary revascularization were recorded. Univariate and stepwise multivariable Cox proportional hazards-models were used to identify the predictors of CE. RESULTS: Eighteen CE were recorded during the follow-up. They were significantly associated with higher summed stress scores on MPI, higher percentage of ischaemic myocardium, higher occurrence of defects in multiple territories and higher CAC score (all with P<0.05). Univariate Cox proportional hazard-models showed that severe perfusion abnormalities as well as CAC score ≥1000 were significantly associated with cardiac events (P<0.0001, P=0.0056). In stepwise Cox proportional hazards-models considering age, gender, history of diabetes mellitus, post-stress left ventricular stunning, the degree of perfusion abnormality and CAC score, only severe perfusion abnormalities and CAC score ≥1000 were independent predictors of CE. There was no CE in patients with normal perfusion, normal function and zero CAC score. CONCLUSION: This study suggests that combined evaluation of MPI and CAC can predict the outcome in ESRD individuals, while severe perfusion abnormality on gated-SPET and high CAC score ≥1000 are predictors of future cardiac events.

Radionuclide cholescintigraphy in genetically confirmed Rotor syndrome.

A 7-year-old girl had been followed up for persistent conjugated hyperbilirubinemia since birth. Alanine aminotransferase, aspartate aminotransferase and γ-glutamyl transpeptidase activity was within the normal range, and liver protein synthesis had always been normal. Infectious etiology of jaundice, autoimmune diseases, drug-induced liver injury, hemolytic anemia, α-1 anti-trypsin deficiency, Wilson disease and Gilbert syndrome were ruled out. At the age of 8 years the patient underwent radionuclide dynamic cholescintigraphy, indicating poor accumulation of the radiotracer in the liver on one hand, and severe retention of the radiopharmaceutical in the blood pool (including the heart) on the other hand. Rotor syndrome was suspected and finally confirmed on molecular analysis. This case represents the first cholescintigraphy report in a pediatric patient with genetically proven Rotor syndrome.

Diagnosis of high-risk patients with multivessel coronary artery disease by combined cardiac gated SPET imaging and coronary calcium score.

OBJECTIVE: The added value of coronary artery calcium (CAC) to SPET for identification of multivessel CAD has not been studied yet. The aim of this original study was to investigate CAC as an adjunct to gated single photon emission tomography (GSPET) in the detection of multivessel coronary artery disease (CAD). SUBJECTS AND METHODS: The study group consisted of 164 prospectively recruited patients without known CAD-123 (75%) men and 60 (37%) women, having diabetes type II, renal insufficiency, left ventricular dilatation and other cardiac problems (arrhythmia, necessity of pharmacological stress test, etc.). The mean age of these patients was 61±12 years (range 34-85 years). All these patients underwent GSPET imaging, CAC score measurement, and coronary angiography. The percentage of ischaemic myocardium, stress and rest left ventricular ejection fraction (LVEF), and transient ischaemic dilation (TID) ratio were measured. RESULTS: Patients with multivessel CAD had more frequently reversible defects in multiple territories, severe ischaemia ≥10% of the left ventricle, stress worsening of the LVEF ≥5%, TID ratio ≥1.17, and CAC score >1000. In the detection of multivessel CAD, the sensitivity of combined assessment of perfusion, function, and CAC (i.e., multiple and/or ≥10% ischaemia, and/or worsening of the LVEF ≥5%, and/or TID ratio ≥1.17, and/or CAC score >1000) was significantly higher than the sensitivity of perfusion alone or perfusion and function alone (81% vs. 55% and 65%, respectively, P<0.05). Sensitivity of only CAC was low (41%). CONCLUSION: Sensitivity of combined assessment of myocardial perfusion, function, and CAC was significantly higher than sensitivity of perfusion alone or perfusion and function alone, suggesting better identification of high-risk patients with CAD.

Myocardial perfusion imaging parameters: IQ-SPECT and conventional SPET system comparison.

Technological advancement in hardware and software development in myocardial perfusion imaging (MPI) leads to the shortening of acquisition time and reduction of the radiation burden to patients. We compared semiquantitative perfusion results and functional parameters of the left ventricle between new dedicated cardiac system with astigmatic collimators called IQ-SPECT (Siemens Medical Solutions, USA) and conventional single photon emission tomography (SPET) system equipped with standard low energy high resolution collimators. A group of randomly selected 81 patients underwent consecutively the MPI procedure on IQ-SPECT and on conventional SPET systen, both without attenuation correction. The summed scores and the values of the functional parameters of the left ventricle: ejection fraction (EF), end-systolic and end-diastolic volumes (ESV, EDV) received from the automatic analysis software were compared and statistically analyzed. Our results showed that summed scores values were significantly higher for the IQ-SPECT system in comparison to the conventional one. Calculated EF were significantly lower for IQ-SPECT, whereas evaluated left ventricular volumes (LVV) were significantly higher for this system. In conclusion, we recorded significant differences in automatically calculated semiquantitative perfusion and functional parameters when compared uncorrected studies obtained by the IQ-SPECT with the conventional SPET system.

Transcranial sonography and (123)I-FP-CIT single photon emission computed tomography in movement disorders.

Diagnosis of Parkinson's disease (PD) can be difficult in the early stages of the disease. The aim of the study described here was to assess the correlation between transcranial sonography (TCS) and (123)I-FP-CIT ([(123)I]ioflupane, N-ω-fluoropropyl-2ß-carbomethoxy-3ß-(4-[(123)I]iodophenyl)nortropane) SPECT (single photon emission computed tomography) findings and the diagnosis of PD. A total of 49 patients were enrolled in the study: 29 patients with PD, 7 patients with other parkinsonian syndromes, 11 patients with essential tremor and 2 with psychogenic movement disorder. Substantia nigra echogenicity was measured using TCS. SPECT was performed using DaTSCAN ([(123)I]ioflupane). TCS and SPECT findings were correlated in 84% of patients, with κ = 0.62 (95% confidence interval: 0.38-0.86). TCS-measured substantia nigra echogenicity and SPECT-measured striatal binding ratio were negatively correlated (r = -0.326, p = 0.003). TCS/SPECT sensitivity, specificity and positive and negative predictive values for the diagnosis of PD were 89.7%/96.6%, 60.0%/70.0%, 76.5%/82.4% and 80.0%/93.3%, respectively. Both positive TCS and SPECT findings correlated significantly with the diagnosis of PD (κ = 0.52, 95% confidence interval: 0.27-0.76, and κ = 0.69, 95% confidence interval: 0.49-0.90, respectively).

Sentinel lymph nodes and planar scintigraphy and SPECT/CT in various types of tumours. Estimation of some factors influencing detection success.

BACKGROUND: Aim ot the study was to assess the role of planar lymphoscintigraphy and fusion imaging of SPECT/CT in sentinel lymph node (SLN) detection in patients with various types of tumours and to estimate some factors influencing detection success - age and body mass index. MATERIAL AND METHODS: Planar scintigraphy and hybrid modality SPECT/CT were performed in 550 consecutive patients (mean age 58.1 ± 13.1 years): 69 pts with gynaecological tumours (37 pts with cervical cancer, 25 pts with endometrial cancer, 7 pts with vulvar carcinoma; mean age 54.4 ± 13.2 years), 161 consecutive patients with melanomas (mean age 57.1 ± 14.8 years), and 320 consecutive women with breast cancer (mean age 59.4 ± 12.0 years). The radiopharmaceutical was injected around the tumour (gynaecologic and breast cancers, melanomas), subareolarly (in some breast cancers), or around the scar (in melanomas after their removal). Planar and SPECT/CT images were interpreted separately by two nuclear medicine physicians. RESULTS: Planar scintigraphy did not show SLN in 77 patients (14.0%): in 8 pts with gynaecologic tumours, in 23 pts with melanomas and in 46 pts with breast cancer. SPECT/CT was negative in 49 patients (8.9%): in 4 pts with gynaecologic tumours, in 12 pts with melanomas and in 33 pts with breast cancer. In 199 (36.2%) patients the number of SLNs captured on SPECT/CT was higher than on planar imaging. 35 foci of uptake (3.1% from totally visible 1134 foci on planar images) interpreted on planar images as hot LNs were found to be false positive non-nodal sites of uptake when further assessed on SPECT/CT. SPECT/CT showed the exact anatomical location of all visualized sentinel nodes. Influence of the age and BMI: The group of patients with higher number of detected SLN on SPECT/CT than on planar scintigraphy had lower average age than the group of patients with the same number of detected SLN on SPECT/CT and on planar scintigraphy, the difference was statistically significant (P=0.008). BMI did not differ between the two groups. CONCLUSION: In some patients with gynaecologic and breast cancers and melanomas, SPECT/CT improves detection of sentinel lymph nodes. It can image nodes not visible on planar scintigrams, exclude false positive uptake and exactly localize axillary, inguinal, pelvic and paraaortic SLNs. It improves anatomical localization of SLNs. We have found the influence of the age on the difference in the number of SLNs detected by the fusion of SPECT/CT and planar lymphoscintigraphy. On the other hand, this difference was not influenced by BMI.

Localisation of sentinel lymph nodes in patients with melanomas by planar lymphoscintigraphic and hybrid SPECT/CT imaging.

BACKGROUND: The aim of the study was to assess the role of planar lymphoscintigraphy and fusion imaging of SPECT/CT in sentinel lymph node (SLN) identification in patients with melanomas. MATERIAL AND METHODS: Planar and hybrid SPECT/low-dose CT lymphoscintigraphy were performed in 113 consecutive patients with melanomas (59 men, 54 women, mean age 57.6 with range 11-87 years, BMI 29.4 ± 12.5). The radiopharmaceutical was injected around the tumour (Group A, 59 patients), or around the scar (Group B, 54 patients). Localisation of melanomas: head and neck 4, trunk 55, upper extremities 28, lower extremities 26. Planar and SPECT/CT images were interpreted separately by two nuclear medicine physicians. Abilities of these two techniques to image SLN were compared. RESULTS: SLNs were detected on lymphoscintigraphy comprising planar and SPECT-CT images in 108 (95.6%) study patients; there was failure to detect SLNs in the remaining 5 (4.4%) patients. Planar images identified 253 SLNs in 100 (88.5%) pts, with a mean of 2.2 ± 1.7 (range 0-9 nodes) per patient. In the remaining 13 (11.5%) patients no SLNs were detected on planar images. On SPECT-CT images, 334 hot nodes were detected in 107 (94.7%) patients with a mean of 3.0 ± 2.1 (range 0-9) nodes per patient. In the remaining 6 (5.3%) patients, SPECT-CT was negative. SPECT/CT visualised lymphatic drainage in 8 (7.1%) patients with non-visualisation on planar imaging. CONCLUSIONS: In some patients with melanomas SPECT/CT improves detection of sentinel lymph nodes. It can image nodes not visible on planar scintigrams, exclude false positive uptake and exactly localize SLNs.

Detection of Sentinel Lymph Nodes in Gynecologic Tumours by Planar Scintigraphy and SPECT/CT.

OBJECTIVE: Assess the role of planar lymphoscintigraphy and fusion imaging of SPECT/CT in sentinel lymph node (SLN) detection in patients with gynecologic tumours. MATERIAL AND METHODS: Planar scintigraphy and hybrid modality SPECT/CT were performed in 64 consecutive women with gynecologic tumours (mean age 53.6 with range 30-77 years): 36 pts with cervical cancer (Group A), 21 pts with endometrial cancer (Group B), 7 pts with vulvar carcinoma (Group C). Planar and SPECT/CT images were interpreted separately by two nuclear medicine physicians. Efficacy of these two techniques to image SLN were compared. RESULTS: Planar scintigraphy did not image SLN in 7 patients (10.9%), SPECT/CT was negative in 4 patients (6.3%). In 35 (54.7%) patients the number of SLNs captured on SPECT/CT was higher than on planar imaging. Differences in detection of SLN between planar and SPECT/CT imaging in the group of all 64 patients are statistically significant (p<0.05). Three foci of uptake (1.7% from totally visible 177 foci on planar images) in 2 patients interpreted on planar images as hot LNs were found to be false positive non-nodal sites of uptake when further assessed on SPECT/CT. SPECT/CT showed the exact anatomical location of all visualised sentinel nodes. CONCLUSION: In some patients with gynecologic cancers SPECT/CT improves detection of sentinel lymph nodes. It can image nodes not visible on planar scintigrams, exclude false positive uptake and exactly localise pelvic and paraaortal SLNs. It improves anatomic localization of SLNs. CONFLICT OF INTEREST: None declared.

I-131 false positive uptake in a huge parapelvic renal cyst.

A male patient had undergone total thyroidectomy for thyroid papillary carcinoma. He was administered thyroablation activity of radioiodine. Whole body imaging after diagnostic activity of 131-I demonstrated intense radioiodine uptake in the right side of the upper abdominal region. The serum thyroglobulin level was low. Ultrasonography demonstrated a large irregular anechoic structure in the centre of the right kidney--a cyst in the parapelvic region. Renal cysts can lead to erroneous interpretation of radioiodine scintigraphy.