68Ga Prostate-specific Membrane Antigen Uptake in Metastatic Medullary Thyroid Carcinoma.

We present the case of a 58-year-old man with advanced medullary thyroid carcinoma who had a treatment history with different types of modalities. In the follow-up, the patient had rising calcitonin and CEA levels. Metastatic lymph nodes, liver, and bone metastases with varying degrees of uptake were detected on 18F-fluorodeoxyglucose (FDG) and 68Ga-DOTATATE positron emission tomography/computed tomography (PET/CT). 68Ga prostate-specific membrane antigen (PSMA) PET/CT was performed to explore whether the patient might have a chance for PSMA-targeted radionuclide therapy, and increased PSMA expression was noted in most of the metastatic lesions, even some of which have higher PSMA uptake than 18F-FDG and 68Ga-DOTATATE.

18F-FDG PET/MRI Image of Skin Metastasis of Ovarian Cancer.

Ovarian cancer is one of the deadliest tumors among women. It mostly metastasizes to the liver, pleura, lungs, and bones. We present a sixty-six-year-old patient with skin lesions. The patient who underwent biopsy due to skin lesions was diagnosed with ovarian cancer. 18F-fluorodeoxyglucose (FDG) positron emission tomography/magnetic resonance imaging (PET/MRI) performed for metastasis search shows widespread skin involvement, especially in the lower abdomen and legs. Skin involvement it ovarian cancer can be rarely seen, and in this article we would like to share 18F-FDG PET/MRI of skin involvement in ovarian cancer.

Incidental Papillary Microcarcinoma and Papillary Thyroid Carcinoma in Multinodular Goiter.

Introduction: This study aimed to examine the incidence of incidental papillary microcarcinoma (PMC) and papillary thyroid carcinoma (PTC) in patients with benign multinodular goiter (MNG) and to compare their relationship with some prognostic factors from a new perspective. Methods: Bilateral total thyroidectomy (BTT) was used to evaluate the data of 716 patients who underwent a surgery for MNG. The prognostic data for these tumors and the relationship between patients with bilateral and multifocal tumors were evaluated using statistical tests. Results: Papillary carcinomas were detected in 201 patients, PMC in 134 of them, and PTCs in 67. Bilaterality was more common in patients with PTCs than in those with PMC. The incidence of bilaterality in male patients with PTC was statistically more common. The presence of intra-tumoral lymphocytes was higher in multifocal PTC cases than in unifocal PTC cases. Conclusion: The results revealed that the number of PMC s was high in incidental tumors, and patients with PTC with male sex, bilaterality, multifocality, and tumor capsule invasion were associated with poor prognosis.

18F-Fluorodeoxyglucose Positron Emission Tomography/Magnetic Resonance Imaging Appearance of Gastrointestinal Behcet's Disease.

Behcet's syndrome (BS) is a variable vessel vasculitis with multi-organ involvement. Recurrent episodes of oral and genital ulcers, papulopustular and erythema nodosum-like skin lesions, and arthritis are relatively more frequent, whereas uveitis, venous and arterial lesions, nervous system, and gastrointestinal involvement are less common, but are severe manifestations. The frequency of gastrointestinal involvement shows important variation between countries as more common in the Far East and the United States, and much less common in Turkey and the Middle East. The main clinical signs of gastrointestinal Behcet's disease include abdominal pain, diarrhea, blood in the stool, fever, and weight loss. Ulcers seen in the terminal ileum, cecum, and ascending colon are common endoscopic findings. Herein, we presented the positron emission tomography/magnetic resonance imaging findings of gastrointestinal involvement in BS.

A case of hepatic focal nodular hyperplasia mimicking hepatocellular carcinoma identified on gallium-68-prostate-specific membrane antigen positron emission tomography/computed tomography.

Prostate-specific membrane antigen (PSMA) is a glycosylated type-II transmembrane protein highly expressed in individual tumor cells. Lesions with PSMA expression in the liver are commonly reported as prostate cancer metastasis or hepatocellular cancer previously. This is the first case reported as hepatic focal nodular hyperplasia, mimicking hepatocellular carcinoma with imaging features. This patient, having a lesion that has been enlarged from 2.0 cm to 2.5 cm in 3 months, was referred to our department for restaging by gallium-68 PSMA (68Ga-PSMA) positron emission tomography/computed tomography (PET/CT). The CT scan showed a focal segment VI hypodensity, which was significantly PSMA-avid. Consequently, its biopsy resulted as focal nodular hyperplasia in liver. His follow-up 68Ga-PSMA PET/CT ultimately revealed a mass lesion of 8 cm of axial diameter.

Active Giant Cell Vasculitis Diagnosis with 68Ga PSMA PET/CT Imaging.

Vasculitis is a multisystem disease characterized by inflammation with infiltration of leukocytes into the blood vessels. Giant cell arteritis (GCA) is the most common form of vasculitis that mostly affects medium- and large-sized arteries. 18Fluorine-fluorodeoxyglucose (18F-FDG) positron emission tomography/computed tomography (PET/CT) is increasingly used to diagnose inflammation of large arteries in GCA. Galium-68 prostate-specific membrane antigen (PSMA) PET/CT has a vital role in the assessment of patients with prostate cancer for recurrence and metastasis of the disease. Various benign and non-prostate malignant conditions may give rise to increased PSMA uptake. Herein, we demonstrate that PSMA uptake can be seen in GCA.

Correlation of SUVmax and Apparent Diffusion Coefficient Values Detected by Ga-68 PSMA PET/MRI in Primary Prostate Lesions and Their Significance in Lymph Node Metastasis: Preliminary Results of an On-going Study

Objectives: Gallium-68 (Ga-68) prostate specific membrane antigen (PSMA) positron emission tomography (PET) has been shown to be more accurate than multiparametric prostate magnetic resonance imaging (MRI) in detection of primary prostate lesions. Using hybrid PET/MRI we aim to detect the correlation between SUVmax and apparent diffusion coefficient (ADC) in primary prostate lesions and to assess their prognostic value in detection of lymph node (LN) metastasis. Methods: Twenty-six patients, who were diagnosed as having prostate cancer with biopsy and underwent Ga-68 PSMA PET/MRI together with biparametric prostate MRI (bpMRI) were included. SUVmax, SUVmean and ADC were recorded for index lesions drawing a region of interest (ROI) of 1 cm2 around the pixel with the highest SUVmax (ROI-1) and another ROI following borders of prostate tumor detected by bpMRI (ROI-2). Presence of LN metastasis was recorded according to PSMA PET/MRI Results: SUVmax was inversely correlated with ADC (ROI-1: p=0.010; ROI-2: p=0.017 for b=800). SUVmax and SUVmeans were both higher in patients with LN metastasis and ADC was lower in patients with LN metastasis for ROI-1. SUVmax cut-off value of 19.8 for ROI-1 and 20.9 for ROI-2 had sensitivity and specificity of 77.8% and 76.5%, respectively for detection of LN metastasis, whereas ADC (b=800) cut-off value of 0.92x10-3 mm2/s had sensitivity and specificity of 87.5% and 76.5%, respectively. SUVmax/ADC (b=800) ratio increased the sensitivity and specificity to 100% and 82.4%, respectively. Conclusion: SUV and ADC values are inversely correlated in primary prostate lesions and the combined use of both values increases the diagnostic accuracy of hybrid PET/MRI in the detection of primary prostate lesions.

The role of FDG PET/CT in detection of distant metastasis in theinitial staging of breast cancer.

BACKGROUND/AIM: We aimed to evaluate the role of FDG PET/CT in the detection of extraaxillary regional nodal/distant metastasis in breast cancer patients and to assess the value of FDG PET/CT for detecting distant metastases in patient subgroups. MATERIALS AND METHODS: A total of 254 patients with breast cancer (248 female, 6 male) who underwent PET/CT for initial staging were enrolled. Patients were divided into four groups: Group 1 consisted of 154 patients diagnosed by tru-cut/core/FNAB, Group 2 comprised 32 patients diagnosed by excisional biopsy, Group 3 included 62 patients who had mastectomy-axillary lymph node dissection, and Group 4 consisted of 6 patients who had axillary lymph node metastasis diagnosed by excisional biopsy. RESULTS: PET/CT detected distant metastasis in 76 of the 254 patients. Of these patients, 21.7% had bone/bone marrow metastasis, 7.1% had lung metastasis, 13% had mediastinal lymph node metastasis, 4.8% had liver metastasis, 9.8% had other organ/system metastasis, and 6% had other lymphadenopathies. According to T staging, the percentages of distant metastasis were as follows: 13.6% of the 66 T1 stage patients, 35.7% of the 129 T2 stage patients, 40% of the 20 T3 stage patients, and 33.3% of the 39 T4 stage patients. CONCLUSION: FDG-PET/CT led to a change in the stage of disease and the treatment approach in newly diagnosed breast cancer patients due to its superiority in detecting extraaxillary regional lymph node metastases and distant metastases.

Sentinel lymph node biopsy under fluorescent indocyanin green guidance: Initial experience.

OBJECTIVE: Sentinel lymph node biopsy can be applied by using either blue dye or radionuclide method or both in breast cancer. Fluorescent imaging with indocyanine green is a new defined method. This study evaluates the applicability of sentinel lymph node biopsy via fluorescent indocyanine green. MATERIAL AND METHODS: IC-VIEW (Pulsion Medical Systems AG, Munich, Germany) infrared visualization system was used for imaging. Two mL of indocyanine green was injected to visualize sentinel lymph nodes. After injection, subcutaneous lymphatics were traced and sentinel lymph nodes were found with simultaneous imaging. Sentinel lymph nodes were excised under fluorescent light guidance, and excised lymph nodes were examined histopathologically. Patients with sentinel lymph node metastases underwent axillary dissection. RESULTS: Four patients with sentinel lymph node biopsy due to breast cancer were included in the study. Sentinel lymph nodes were visualized with indocyanine green in all patients. The median number of excised sentinel lymph node was 2 (2-3). Two patients with lymph node metastasis underwent axillary dissection. No metastasis was detected in lymph nodes other than the sentinel nodes in patients with axillary dissection. There was no complication during and after the operation related to the method. CONCLUSION: According to our limited experience, sentinel lymph node biopsy under fluorescent indocyanine green guidance, which has an advantage of simultaneous visualization, is technically feasible.

The role of FDG-PET/CT in detecting unsuspected and unknown distant metastasis in the initial staging of NSCLC.

BACKGROUND/AIM: Our purpose in this retrospective study was to determine the ratio of unexpected [metastases within the coverage area of thorax computed tomography (CT)] and unknown (metastases out of the coverage area of thorax CT) metastases by positron emission tomography/CT (PET/CT) in patients with newly diagnosed non-small cell lung cancer (NSCLC) who had no defined metastatic lesion, and to investigate the contribution of fludeoxyglucose (FDG)-PET/CT in metastasis staging. MATERIALS AND METHODS: A total of 567 patients (489 males and 78 females, mean age 60.9 ± 10.7 years) were enrolled in this study. Among the 567 patients, a total of 156 patients who underwent PET/CT for metabolic characterization (group 1) and had solitary pulmonary nodules (group la, n = 39) or solitary pulmonary masses (group lb, n = 117) and the remaining 411 patients (group 2) with NSCLC who had PET/CT performed for staging formed the basis of this study RESULTS: In group 1, 5/39 (12.8%) patients with a solitary pulmonary nodule and 29/117 (24.8%) patients with a solitary pulmonary mass had distant metastases. In group 2, 129 patients of 411 (31.4%) had distant metastasis. CONCLUSION: FDG-PET/CT is proven to be an effective method in detection of unsuspected-unknown metastasis, either in patients with solitary pulmonary lesion or in the initial staging of patients with NSCLC.