Interreader agreement in evaluation of 68Ga-PSMA PET/CT at the time of initial staging: comparison of the three evaluation criteria in the pretreatment risk groups.

OBJECTIVE: The aim of this study was to assess the interreader agreement in evaluation 68Ga-prostate-specific membrane antigen (PSMA) PET/CT according to three current criteria European association of nuclear medicine, PROMISE with miTNM, and PSMA-RADS in newly diagnosed prostate cancer (PC) patients. METHODS: The images of 101 patients who had been diagnosed with PC and underwent 68Ga-PSMA PET/CT at the time of initial staging were evaluated according to the three interpretation criteria by two nuclear medicine specialists. Local tumor, pelvic lymph node metastasis and distant metastasis were evaluated separately. Abdominal lymph nodes, bone and visceral organ metastases were additionally evaluated as subregions of distant metastatic sites. Patients were evaluated in subgroups Gleason score ≥8 or prostate-specific antigen ≥20 ng/mL as the high-risk group (HR) and prostate-specific antigen ≤ 20 ng/mL and Gleason score <8 as the low-risk group (LR). To measure interreader agreement for each judgment site Cohen's Kappa statistic coefficient (κ) was calculated. RESULTS: All three criteria European association of nuclear medicine, PROMISE with miTNM and PSMA-RADS exhibit substantial and almost perfect agreement between the readers in all sites except for PSMA-RADS in bone and visceral metastasis (κ = 0.495, κ = 0.506, respectively). According to the risk groups, a remarkable difference in interreader agreement for bone metastasis for all three criteria (especially in PSMA-RADS) between the HR and LR patients was detected. CONCLUSIONS: In low-risk patients especially PSMA-RADS criteria leads to increased interreader reporting differences. While evaluating 68Ga-PSMA PET/CT images it should be considered that pretreatment risk levels of PC patients could affect the interreader agreement.

[Evaluation of solid pulmonary nodules in patients with bladder cancer with computed tomography based texture analysis method: Is it possible to differentiate metastatic - non-metastatic nodules?] / Bilgisayarli tomografi tabanli doku analizi yöntemi ile mesane kanserli hastalarda solid pulmoner nodüllerin degerlendirilmesi: Metastatik - metastatik olmayan nodül ayrimini yapmak mümkün mü?

INTRODUCTION: Solid Pulmonary Nodule (SPN) is defined as parenchymal radiopacity smaller than 3 cm in diameter. Evaluating the metastatic nature of the SPNs detected in the thorax computed tomography (TCT) examination for staging purposes in cancer patients becomes a fundamental problem for the physician. Invasive procedures, additional imaging or follow-up imaging, are often used to differentiate metastatic and non-metastatic nodules. In this study, we aimed to distinguish SPNs detected in patients diagnosed with bladder cancer (BC) as metastatic and non-metastatic nodules by texture analysis. MATERIALS AND METHODS: TCT images of patients diagnosed with BC in our hospital from January 2007 until December 2017 were retrospectively evaluated. A total of 46 patients with SPN, including metastatic (n= 19) and non-metastatic (n= 27), were included in the study. Short axis diameter, long-axis diameter, nodule volume and volume histogram values of the nodules were obtained. Chisquare test was used to evaluate dependent variables, and the Mann-Whitney U test was used to evaluate independent variables. ROC curves of the obtained data were plotted. Statistically, the significant p-value was determined as less than 0.05. RESULT: A significant difference was found between SPN long axis, short axis and volume values. In the volumetric histogram analysis, the maximum density value and the mean density value were found to be statistically significant. When the average of the highest densities in the volume histogram data was evaluated, the area under the curve value was 0.702 (95% CI, 519-854). The metastatic nodule could be distinguished with a sensitivity of 88% and a specificity of 70% when the volume histogram has the maximum density threshold of 50 HU. CONCLUSIONS: In this study, we concluded that SPN detected on CT images can be distinguished as metastatic and non-metastatic nodules using texture analysis method without invasive procedures.

Three cases of immunoglobulin G4-related respiratory disease with uncommon imaging findings.

BACKGROUND: Immunoglobulin G4-related disease (IgG4-RD) is a rare multisystemic idiopathic fibroinflammatory disorder. The rare form of IgG4-RD with isolated thorax involvement is called immunoglobulin G4-related respiratory disease (IgG4-RRD). IgG4-RRD, which is reported in a limited number of cases in the literature, can be categorized into four types on the prevalent chest computed tomography (CCT) findings: solid nodular, round-shaped ground-glass opacity, alveolar interstitial, and bronchovascular. Solid nodular form of IgG4-RRD with mass-like lesions is sporadic and described in the literature with a small number of case reports. OBJECTIVES/METHODS: We aim to present the radiologic, pathologic, and clinical findings of three cases of IgG4-RRD mimicking lung cancer. RESULTS: In all three patients, IgG4-RRD occurred with mass-like lesions in the thorax. In case-1 and 2, CCT showed multiple, nodular lesions and multiple mediastinal lymph nodes. On positron emission tomography with 2-deoxy-2-[fluorine-18] fluoro- D-glucose integrated with computed tomography (18F-FDG PET/CT), the masses showed increased 18F-FDG uptake in case-2 and 3. The gold standard histopathological verification for IgG4-RRD was provided for all cases. CONCLUSIONS: IgG4-RD is an immune-mediated condition comprised of a collection of disorders that share particular pathologic, radiologic, serologic, and clinical features. Isolated IgG4-RRD is rarely seen and is available in the literature as case reports. IgG4-RRD, which can make lung involvement in different patterns, rarely appears with mass-like lesions. Still, IgG4-RRD must be considered in the differential diagnosis of mass lesions detected in CCT. Laboratory, radiological, and histopathological findings of the disease should be evaluated together for an accurate diagnosis.

Evaluation of 68Ga-PSMA PET/CT with volumetric parameters for staging of prostate cancer patients.

BACKGROUND: The aim of this study was to investigate the relationship between volumetric data obtained from staging 68Ga-prostate-specific membrane antigen (PSMA) PET computerized tomography (CT) images with prostate-specific antigen (PSA), risk groups, Gleason Grade (GG) groups and presence of metastasis. METHODS: We performed a retrospective analysis of 68Ga-PSMA PET-CT images from 88 patients undergoing initial staging of prostate adenocarcinoma between January 2015 and September 2018. Images were evaluated in LIFEx software; PSMA involvement above the background activity in prostate gland, lymph node and other distant metastases was plotted with 40% SUVmax threshold, SUVmax, PSMA tumor volume (PSMA-TV) and total lesion PSMA (TL-PSMA) values were obtained. RESULTS: In all patients, there was a moderate correlation between PSA and PSMA-tumor volume whole-body (PSMA-TVwb) (P < 0.001, r = 0.580) and a high correlation between total lesion-PSMAwb (TL-PSMAwb) (P < 0.001, r = 0.636). Prostate PSMA-TV (PSMA-TVp) and TL-PSMA (PSMA-TVp) values were different in local and locally advanced/metastatic patients (P = 0.020 and 0.006, respectively). PSMA-TVp and TL-PSMAp values were significantly different in low-moderate and high-risk patients (P = 0.003 and <0.001, respectively), and in patients with and without metastasis (P = 0.008 and <0.001, respectively). PSMA-TVp, PSMA-TVwb, TL-PSMAp and TL-PSMAwb values were significantly different in patients with GG ≤3 and >3 (P = 0.030, 0.002, <0.001 and <0.001, respectively). CONCLUSION: Pretreatment 68Ga-PSMA PET/CT volumetric parameters provides unique data to use in the clinical decision-making process of patients with adenocarcinoma of the prostate.

Factors affecting overall survival and progression-free survival in patients with metastatic castration resistant prostate cancer received 177Lu PSMA I&T therapy.

OBJECTIVE: Lutetium-177 (177Lu) prostate specific membrane antigen (PSMA) radionuclide therapy (RNT) is an effective and safe treatment option in patients with metastatic castration resistant prostate cancer (mCRPC). The first aim of this study was to determine RNT response rate. The second and main aim of this study is measure overall and progression-free survival (OS and PFS) and to determine the factors have effect on OS and PFS. MATERIAL AND METHODS: Patients with mCRPC had 177Lu PSMA RNT every 6-8 weeks. Therapy response of each cycle determined wit PSA after 6-8 weeks. Overall survival and PFS were measured, then effects of age, Gleason grade, local recurrence, extraabdominopelvic located lymph node metastasis, visceral metastasis, prostate specific antigen (PSA) changing after the first RNT, pretreatment PSA, hemoglobin (Hb), alkaline phosphatase (ALP) and lactate dehydrogenase (LDH) values on survivals were determined. RESULTS: Forty-five patients were treated with total of 164 cycles of RNT. Fifteen patients (33%) had PSA decline of ≥50%, 23 patients (51%) showed any PSA decline and 20 patients (44%) showed PSA increase of ≥25%. Median OS and PFS were 17,1 months and 7,4 months. Patients had any or ≥50% PSA response after the first cycle, lower initial ALP (<120U/L) had longer OS and PFS. Patients had normal Hb showed longer OS and patients had lower initial PSA (<51ng/mL) had longer PFS. Patients had PSA progression of ≥25% had shorter OS and PFS. CONCLUSION: Prostate specific antigen response after the first cycle, lower initial ALP is related to longer OS and PFS. Normal pretreatment Hb is a predictor of longer OS and lower initial PSA is related to longer PFS. Prostate specific antigen progression after the first cycle causes shorter OS and PFS.

Determining residual adipose tissue characteristics with MRI in patients with various subtypes of lipodystrophy.

PURPOSE: We aimed to investigate residual adipose tissue with whole-body magnetic resonance imaging to differentiate between subtypes of lipodystrophy. METHODS: A total of 32 patients (12 with congenital generalized lipodystrophy [CGL], 1 with acquired generalized lipodystrophy [AGL], 12 with familial partial lipodystrophy [FPLD], and 7 with acquired partial lipodystrophy [APL]) were included. RESULTS: Despite generalized loss of metabolically active adipose tissue, patients with CGL1 caused by AGPAT2 mutations had a significant amount of residual adipose tissue in the scalp, earlobes, retro-orbital region, and palms and soles. No residual adipose tissue was noted particularly in the head and neck, palms and soles in CGL2 caused by BSCL2 mutations. CGL4 caused by mutations in the PTRF gene was characterized with well-preserved retro-orbital and bone marrow fat in the absence of any visible residual adipose tissue in other areas. No residual adipose tissue was observed in AGL. Despite loss of subcutaneous fat, periarticular adipose tissue was preserved in the lower limbs of patients with FPLD. Retro-orbital adipose tissue was surprisingly preserved in APL, although they lacked head and neck fat. CONCLUSION: Lipodystrophies are a heterogeneous group of disorders characterized by generalized or partial loss of adipose tissue, which can be congenital or acquired. Our results suggest that residual adipose tissue characteristics can help distinguish different subtypes of lipodystrophy.

Response to Cabazitaxel Beyond 20 Cycles in A Patient with Penile Metastasis of Prostate Cancer: A Case Report.

Penile metastases are extremely rare events and generally occurs at a late stage of primary disease. They mostlyoriginate from prostate and bladder in the genitourinary tract. Penile metastases have a dismal prognosis and verylow survival rates. We report a case of penile metastasis in 70-year-old geriatric male patient with prostatic adenocarcinomawho was treated with cabazitaxel chemotherapy beyond 20 cycles with a good response and acceptableminimal toxicity.

Pseudomyogenic (Epithelioid sarcoma-like) hemangioendothelioma with bone invasion.

AIM: Pseudomyogenic (epithelioid sarcoma-like) hemangioendothelioma is a rare local aggressive vascular tumor. Herein we present a 54-year-old male patient with a tumor on his index finger. CASE: The patient presented with a 1-year history of pain and swelling that progressively exacerbated. Bone invasion was observed on the middle phalanx via direct radiography. Histopathological examination findings were compatible with epithelioid sarcoma-like hemangioendothelioma. CONCLUSION: To the best of our knowledge is the first case report of epithelioid sarcoma-like hemangioendothelioma with bone invasion.

HMB45 and melan-A expression in renal angiomyolipoma and their significance for the diagnosis.

AIMS AND BACKGROUND: The melanosome-associated proteins, also called HMB45 and melan-A, are also present in renal angiomyolipoma. The aim of the present study was to evaluate the expression of HMB45 and melan-A in mesenchymal cells of renal angiomyolipoma and to investigate their significance in the differential diagnosis. METHODS: Twelve patients, 9 females and 3 males diagnosed with renal angiomyolipomas, were included in the present study. The most representative tumor tissue block was chosen from each case, and 5-microm sections were taken to poly-L-lysin-coated slides for immunohistochemical staining. The standard streptavidin-biotin immunoperoxidase method was used for immunostaining with HMB45 and melan-A antibodies. RESULTS: All of the cases showed positive cytoplasmic immunostaining for HMB45 and melan-A. Melan-A expression was shown in smooth muscle component, adipose tissue and predominantly in the perivascular cells, whereas HMB45 immunoreactivity was stronger than melan-A expression in all cases. CONCLUSIONS: It was concluded that HMB45 and melan-A reactivity is a useful tool to distinguish renal angiomyolipomas from other primary and secondary mesenchymal and primary epithelial tumors. Melan-A and HMB45 share similar specificities for renal angiomyolipoma. In addition, such expression in renal angiomyolipomas may occur without any evidence of nevomelanocytic differentiation. Further research is required to determine the histogenesis of this entity.