Gaetano Paone

Thyroid lobe ablation with iodine- ¹³¹I in patients with differentiated thyroid carcinoma: a randomized comparison between 1.1 and 3.7 GBq activities.

Purpose The present study was undertaken to evaluate the ablation rate after administration of 1.1 or 3.7 GBq of iodine-131 (131I) to patients with low-risk differentiated thyroid carcinoma (DTC) primarily treated by lobectomy. Patients and methods Enrolled were 136 consecutive patients affected by histologically proven low-risk DTC previously treated by lobectomy. Patients were randomized to receive a single dose of 1.1 or 3.7 GBq of 131I in an equivalence trial. Successful thyroid ablation was defined as a negative diagnostic whole-body scan and stimulated thyroglobulin levels lower than 2 ng/ml in the absence of thyroglobulin antibodies. Results The patient demographic and clinical data were well balanced at baseline. The ablation rate was significantly (P<0.01) higher in patients treated with 3.7 GBq (75%) than in those treated with 1.1 GBq (54%) of radioiodine. No relevant side effects occurred in either group. Conclusion Radioiodine lobe ablation with a single administration of 3.7 GBq is a simple and safe mode of treatment, achieving an ablation rate higher than that of 1.1 GBq. This procedure may be offered as an alternative to completion thyroidectomy in highly selected DTC patients who had experienced complications during initial surgery or for whom completion thyroidectomy is contraindicated.

Thyroid nodules with indeterminate cytology: prospective comparison between 18F-FDG-PET/CT, multiparametric neck ultrasonography, 99mTc-MIBI scintigraphy and histology

PURPOSE To evaluate the role of (18)F-flurodeoxiglucose positron emission tomography/computed tomography ((18)F-FDG-PET/CT) in predicting malignancy of thyroid nodules with indeterminate cytology. PATIENTS AND METHODS We analysed 87 patients who have been scheduled to undergo surgery for thyroid nodule with indeterminate cytology. All patients underwent (18)F-FDG-PET/CT, multiparametric neck ultrasonography (MPUS), and (99m)Tc-methoxyisobutylisonitrile scintigraphy ((99m)Tc-MIBI-scan). Histopathology was the standard of reference. We compared the sensitivity (SE), specificity (SP), accuracy (AC), positive (PPV) and negative predictive (NPV) values of (18)F-FDG-PET/CT with those of (99m)Tc-MIBI-scan and MPUS in detecting cancer. Univariate and multivariate analyses evaluated the association between each diagnostic tool and histopathology. RESULTS On histopathology, 69 out of 87 nodules were found to be benign and 18 to be malignant. The SE, SP, AC, PPV and NPV of (18)F-FDG-PET/CT were 94, 58, 66, 37 and 98% respectively. The SE, AC and NPV of (18)F-FDG-PET/CT were significantly higher than those of MPUS and (99m)Tc-MIBI-scan. The association of both positive (18)F-FDG-PET/CT and MPUS (FDG+/MPUS+) showed significantly lower SE (61% vs 94%) and NPV (88% vs 98%) than (18)F-FDG-PET/CT alone, but significantly higher SP (77% vs 58%). On univariate analysis, (18)F-FDG-PET/CT and the combination of FDG+/MPUS+ and of FDG+/MIBI- were all significantly associated with histopathology. On multivariate analysis, only FDG+/MIBI- was significantly associated with histopathology. CONCLUSION The AC of (18)F-FDG-PET /CT in detecting thyroid malignancy is higher than that of (99m)Tc-MIBI-scan and MPUS. A negative (18)F-FDG-PET/CT correctly predicts benign findings on histopathology. The association of FDG+/MPS+ is significantly more specific than (18)F-FDG-PET/CT alone in identifying differentiated thyroid cancer. A positive (18)F-FDG-PET/CT is significantly associated with malignancy when qualitative (99m)Tc-MIBI-scan is rated as negative.

Bone Marrow Involvement in Unknown Acute Myeloid Leukemia Detected by 18F-FDG PET/MRI.

A 83-year-old patient with inflammatory syndrome, unknown fever, and intense lumbar pain underwent diagnostic imaging for suspicion of spondylodiscitis. Fused F-FDG PET/MRI images showed heterogeneous hypermetabolism in the lumbar spine characterized by infiltrative lesions and adjacent necrotic tissue. Peripheral blood analysis revealed leukoerythroblastic changes, whereas bone marrow biopsy was highly hypercellular and revealed an acute myeloid leukemia with 70% infiltration of blasts of erythroid lineage. The intensive lumbar pain and elevated lactate dehydrogenase level are suggestive of bone marrow necrosis as seen in the PET/MRI. Our case emphasizes the usefulness of fused PET/MRI imaging for metabolic characterization of AML.

Metastatic undifferentiated spindle cell sarcoma of the thyroid gland evaluated by 18F-FDG PET/CT.

We describe a rare case of metastatic undifferentiated spindle cell sarcoma (USCS) of the thyroid gland evaluated by 18F-FDG PET/CT. A 63-year-old male patient with histological diagnosis of USCS of the thyroid gland underwent 18F-FDG PET/CT for staging. PET/CT revealed increased radiopharmaceutical uptake corresponding to a thyroid mass and mild 18F-FDG uptake in a 7-mm lung nodule, which was diagnosed as USCS metastasis. Based on these findings, the patient was referred to surgery and chemotherapy, but he died 6 months later for disease progression.

Multifocal epithelioid hemangioendothelioma of the lower limbs detected by 18F-FDG PET/MRI.

A 38-year-old man underwent surgical excision of a 1.5-cm subcutaneous nodule of the left leg. Histologic evaluation demonstrated the presence of an epithelioid hemangioendothelioma (EHE). The patient underwent 18F-FDG PET/MRI for staging. This examination demonstrated the presence of several soft tissue and bone lesions in the left lower limb without evidence of distant metastatic disease. The final diagnosis was multifocal EHE of the left lower limb. In this case, 18F-FDG PET/MRI has been very useful in the correct staging of this rare presentation of EHE of the lower limbs.

Incidental detection of Hürthle cell adenoma by 18F-choline PET/CT scan in a patient with prostate cancer

A 64-year-old male patient with increased serum level of prostate-specific antigen (23 ng/ml) and histological diagnosis of prostate cancer (Gleason score: 9) underwent 18F-choline PET/CT for staging. PET/CT images detected multiple areas of abnormal radiopharmaceutical uptake corresponding to the primary prostate tumor and several lymph nodal and bone metastases (Fig. 1). Furthermore PET/CT scan showed an area of increased 18F-choline uptake

Added value of fused somatostatin receptor imaging/magnetic resonance imaging in a rare case of paraganglioma of the urinary bladder

Whole-body SRS at 4h was normal whereas delayed SRS at 24hshowed an area of increased radiopharmaceutical uptake corre- to the urinary bladder (Fig. 1). to this SRS finding, the patient underwent a magnetic res- imaging (MRI) of the pelvis and, in order to better localizethe ofincreasedradiopharmaceuticaluptake,fusedSPECT/MRI wereperformed.MRIdemonstratedthepresenceofa1.5cm in theinferior wall of urinary bladder corresponding

Real-time elastography in autonomously functioning thyroid nodules: relationship with TSH levels, scintigraphy, and ultrasound patterns

BackgroundReal-time elastography has been proposed to increase the sensitivity of ultrasound and improve the detection of thyroid nodules at risk of malignancy. To date sparse data on real-time elastography assessment of autonomously functioning thyroid nodules exist. Here, we investigated the potential role of real-time elastography in autonomously functioning thyroid nodule assessment. Specifically, the correlation between serum hormones and real-time elastography score, as well as other clinical and ultrasound features, was analyzed.MethodsPatients with autonomously functioning thyroid nodule identified by I-123 scintigraphy from September 2015 to July 2016 and undergoing ultrasound, real-time elastography, and thyroid function evaluation were selected. All autonomously functioning thyroid nodule were classified as RTE I (prevalence of red or green color with blue in up to 25% of the nodule area), RTE II (blue in 25–75%), or RTE III (blue in more than 75%). The association between suppressed thyroid stimulating hormone and patient’s age, nodule’s size, ultrasound presentation, and real-time elastography scoring was analyzed by Odds Ratio in univariate fashion and multivariate model.ResultsA number of 47 subjects with single autonomously functioning thyroid nodule were enrolled. Median age of 63 years, median size of 2.0 cm, and suppressed thyroid stimulating hormone levels in 32% of cases were found. Those nodules classified by ultrasound at high risk underwent fine-needle aspiration cytology and cancer was excluded. At real-time elastography evaluation, a 45% of autonomously functioning thyroid nodule had a hard appearance (RTE III) and had thyroid stimulating hormone significantly lower than the other (p < 0.0001). A model of multivariate logistic regression including nodule’s size, ultrasound characteristics, and elastographic presentation showed that only RTE III was significantly associated with suppressed thyroid stimulating hormone (Odds Ratio of 50).ConclusionsAutonomously functioning thyroid nodule may have variable elasticity at real-time elastography examination, being hard score associated with reduced/suppressed thyroid stimulating hormone. For clinical practice, the presence of autonomously functioning thyroid nodule should be considered in patients with hard lesions. Also, as quoted by the most recent ATA guidelines, elastography should not be accounted for risk stratification of thyroid nodules.

A case of optic neuritis incidentally detected by somatostatin receptor scintigraphy

An 18-year-old female patient with increased serum chromogranin-A value (100 U/L; normal value < 90 U/L) underwent somatostatin receptor scintigraphy (SRS) with 111In-pentetreotide searching for the presence of a neuroendocrine tumor. SRS was performed after i.v. administration of 200 MBq of 111In-pentetreotide. Whole-body scans were obtained 4 h and 24 h after the radiopharmaceutical administration and completed by tomographic images (SPECT) of the head, neck, thorax, abdomen and pelvis, performed 24 h after the radiopharmaceutical injection. Whole-body SRS at 4 h was normal. SPECT images performed at 24 h showed an area of linear and moderately increased radiopharmaceutical uptake corresponding to the left orbitary region (Fig. 1A). No other areas of increased radiopharmaceutical uptake were detected in the rest of the body.

Colorectal carcinoma with bone metastases detected by 18F-choline PET/CT.

We report a case of metastatic colorectal carcinoma detected by F-choline PET/CT. A 72-year-old man with history of prostate cancer (previously treated with prostatectomy) underwent F-choline PET/CT for restaging. PET/CT revealed a focal area of increased F-choline uptake corresponding to a rectal nodule. Furthermore, 2 areas of increased radiopharmaceutical uptake were evident in the right clavicle and in the body of the 10th dorsal vertebra, corresponding to the osteolytic lesions. Based on these PET/CT findings, the patient underwent biopsy of the rectal nodule and left clavicular lesion. Histologic examination demonstrated the presence of a colorectal carcinoma metastatic to the bone.