Titoit hastaliklarinda radyoaktif iyot kullaniminin ilk yillarina ait calismalar hipertiroidi konusunda yogunlasmistir Saul Hertz’un basarili calismalari, hipertiroidi tedavisinde edinilen basarinin dogal olarak kanser tedavisine aktarilabilecegi inancini dogurmustur. Ilk calismalarin teranostik gostergeleri daha sonraki yillarda gidedrek guclenecek olan nukleer onkolojinin bilimsel ve felsefi temelini olusrturmasi itibariyle “ontolojik” bir oneme haizdir. Bu ontolojik temeli atan Dr. Saul Hertz Harvard Universitesi ile baglantili calisan Massachusetts General Hospital Tiroit klinigi kurucu direktorudur. Hertz bugunku bilgilerimize esas olmus tiroit teranostik caismalarini 1937-1942 yillari arasinda surdurmustur. Radyoaktif iyot ile Ilk tiroit kanseri tedavisi 1942 de Samuel Seidlin tarafindan uygulanmistir. Ilk uygulamanin sansayonel etkisi, ilginc olarak, bilimsel verileri golgeleyecek kadar guclu olmustur. Kavramin gelismasinde erken yillarda teorik fizik ve nukleer instrumantasyonlardaki gelismelerin ve bu gelismelere imza atan bilim adamlarinin buyuk katkilari olmustur. Nukleer tip alaninda ise William H. Beierwaltes en onemli katkilari olan bir klinik arastirmaci olarak tarihimize gecmistir. Onunla baslayan klasik paradigma bizleri bugunun molekuler teranostik gorus acisina kadar tasimistir. Bundan boyle molekuler patoloji ve yeni teranostik acilimlar ile nukleer onkoloji artik yeni bir ontolojik kimlige kavusacaktir.

The early history of radioactive iodine (RAI) use in thyroid disease is well-cultivated in the literature, yet largely oriented towards hyperthyroidism. Saul Hertz’s success with RAI in thyrotoxicosis fueled a seamless transition to Samuel Seidlin’s investigations with RAI in thyroid cancer. These landmark events embody nuclear ontology, a philosophical foundation for the creation and existence of radiotherapeutic principles that continue to influence clinical practice today. Saul Hertz of the Massachusetts General Hospital Thyroid Clinic created a framework for RAI theranostics with preclinical experiments and clinical cases from 1937-1942. Samuel Seidlin of Montefiore Hospital consulted Hertz on the feasibility of using RAI for thyroid cancer in 1942. Seidlin and colleagues assembled a sixteen-patient series showcasing a unique entity: functional thyroid metastases that respond to RAI. Other investigations at the time demonstrated that RAI had little efficacy as a therapeutic agent, mainly because most thyroid tumors do not form colloid, and therefore cannot concentrate RAI. These findings were soon overshadowed by a mainstream article in the October 1949 issue of Life that portrayed RAI as a lifesaving therapy for thyroid cancer. The paradigm was set, and later writings by William H. Beierwaltes and other prominent nuclear medicine physicians established the primary goals and principles of RAI therapy. This paper examines controversial topics in the advent of thyroid theranostics, and applies historical significance to current discussions on the role of RAI in thyroid cancer management. Another paradigm shift is on the horizon as thyroidology enters the age of genomics. The molecular theranostic profiles will soon be incorporated into a dynamic clinical decision-making and management algorithm for thyroid surgery and RAI therapy.

GİRİŞ ve AMAÇ: Çalışmamızda, Ga-68 PSMA PET-BT taramanın SUVmax’ı, başlangıç evrelemede orta ve yüksek riskli PCa’ni tahmin edebilir mi? Oligometastatik PCa’ni tahmin edebilir mi? Sorularına cevap aradık.

YÖNTEM ve GEREÇLER: TRUS-Bx temelinde Prostat CA tanısı almış ve Ga-68 PSMA PET-CT tarama yapılmış 50 hastanın görüntüleri retrospektif olarak incelendi. Primer tm’de PSMA ekspresyonunun en yüksek olduğu alanın SUVmax değeri ile risk gruplarının ve metastaz durumunun korelasyonu yapıldı.

BULGULAR: Oligometastatik hastalarda SUVmax değeri 6,18 iken, multiple metastazı olan olgularda 10,93 olarak bulundu (p=0,037). Multiple metastaz için cut-off SUVmax değeri 7,96 olarak bulundu (p=0,047). Regresyon modelinde, SUVmax’ın katkısı pozitif yönlü (OR=1.42) ve anlamlı bulundu (p=0.038). Orta risk grubunda SUVmax değeri 6,91 iken, yüksek risk grubunda 11,44 olarak bulundu (p=0,014). Yüksek risk grubu için cut-off SUVmax değeri 10,55 olarak bulundu (p=0,006). Regresyon modelinde, SUVmax’ın katkısı pozitif yönlü (OR=1.198) ve anlamlı bulundu (p=0.021).
TARTIŞMA ve SONUÇ: Bu çalışma ile yeni tanı almış PCa'de primer tm’ün SUVmax değerinin, gleason skoru ile korele olduğunu gösterdik. SUVmax’ın, D’Amico risk sınıflamasına göre orta ve yüksek riskli PCa’ni yüksek doğrulukla tahmin edebileceğini düşünüyoruz. SUVmax’ın tedavi yaklaşımı açısından önem arz eden oligometastatik PCa’ni yüksek doğrulukla tahmin edebileceğini düşünüyoruz.

INTRODUCTION: In this study, we aimed to investigate whether Ga-68 PSMA PET-CT scanning is adequate to predict intermediate risk, high risk or oligometastatic PCa as an initial staging modality

METHODS: The Ga-68 PSMA PET-CT scan images of 50 PCa patients pathologically proved by transrectal ultrasound guided biopsy (TRUS-Bx) were evaluated retrospectively. The association of SUVmax value of the area with the highest PSMA expression within primary tumor with the risk groups and metastatic burden is investigated.

RESULTS: SUVmax value was 6,18 in oligometastatic patients where it was measured as 10,93 in patients with higher metastatic burden (p=0,037). Cut-off value of SUVmax value for multiple metastasis was found 7,96 (p=0,047). According to regression model, SUVmax value was found to have a positive influence (OR=1.42) which was statistically significant (p=0.038). SUVmax value for intermediate and high risk patients was 6,91 and 11,44 respectively (p=0,014). Cut-off value of SUVmax value for high risk group was 10,55 (p=0,006). In regression model, SUVmax value was found to have a positive influence (OR=1.198) which was statistically significant (p=0.021).

DISCUSSION AND CONCLUSION: With this paper we demonstrated the association between SUVmax value of primary tumor and gleason score. Our results also allowed us to suggest primary tumor SUVmax as a sufficiently accurate predictor of D’Amico risk groups in newly diagnosed PCa cases. Additionally, Ga-68 PSMA PET-CT turns out to be useful tool for determining oligometastatic PCa patients accurately.

GİRİŞ ve AMAÇ: Bu çalışmada anterior mediastinal kitlelerin karakterizasyonunda FDG PET/BT'nin rolü değerlendirilecektir.
YÖNTEM ve GEREÇLER: Anterior mediastinal kitle tanısıyla Nükleer Tıp Bölümüne Kasım 2016-Eylül 2017 tarihleri arasında metabolik karakterizasyon amacıyla başvuran hastaların onkolojik FDG PET/BT görüntüleri geriye dönük olarak değerlendirildi. Kırk bir hasta (17 K, 24 E; 16-83, ortalama yaş: 50,5 ± 19,5) çalışmaya dahil edildi.
BULGULAR: Çalışmaya dahil edilen hastalardan iki hastanın lezyonu benign olarak tanımlandı (SUVmax<3) ve ikisinin patolojisi tümör dışı lezyonlardı (Tüberküloz ve Sarkoidoz). Malignite tanısı konulan hastaların kitlelerinin ortalama boyutu ve SUVmax değerleri sırasıyla; 6,4±3,7 cm ve 11,9±9,6 idi. Malign tümörlerin patolojik tanıları; timik tumörler (n=8), lenfoma (n=8), akciğer kanseri (n=11), karsinoid metastazı (n=2), tiroid karsinomu (n=2), germ hücreli tümör (n=1), schwannoma (n=1) ve sarkom (n=1) idi.
TARTIŞMA ve SONUÇ: Bilinen nedenlerin aksine anterior mediastinal kitlelerin patoloji sonuçları anterior mediastinal yapıların tümörlerinin veya karsinomlarının dışındaki patolojilerden kaynaklanabilir. Bu seride timik tümörlere göre lenfoma ve akciğer karsinomu daha sık rastlanan patolojilerdi.

INTRODUCTION: The role of FDG PET/CT in the diagnosis of the anterior mediastinal masses will be evaluated in this study.
METHODS: The retrospective evaluation of the images of oncologic FDG PET/CT images of the patients who attended to Nuclear Medicine Department between November 2016 and September 2017 for the metabolic characterization of anterior mediastinal mass was performed. Forty one patients were included in the study (17 F, 24 M; 16-83, mean: 50,5 ± 19,5 years old).
RESULTS: Among these patients’ lesions four was characterized as benign (SUVmax<3) and two patients pathology results were non tumoral lesions (Tuberculosis and Sarcoidosis). The mean dimensions and SUVmax levels of the malign lesions of the patients was 6,4±3,7 cm and11,9±9,6 respectively. The pathology results of the malign tumors were thymus tumors (n=8), lymphoma (n=8), lung cancer (n=11), carcinoid metastasis (n=2), thyroid carcinoma (n=2), germ cell carcinoma (n=1), schwannoma (n=1) and sarcoma (n=1).
DISCUSSION AND CONCLUSION: Contrary to the known causes of the anterior mediastinal mass there might originate from other structures than anterior mediastinal structures. In this study the lymphoma and lung carcinoma pathology were more frequent than thymic lesions.

GİRİŞ ve AMAÇ: Birçok çalışmada, koroner arter hastalığı ile inflamatuar parametreler arasında ilişki bulunduğu gösterilmiştir. Bununla birlikte, SPECT miyokard perfüzyon görüntülemesinde (MPI) iskemi bulunan hastalardaki C-reaktif proteinin (CRP)/ albümin oranının (CAR) rolü ile ilgili yeterli veri bulunmamaktadır. Bu çalışmada, SPECT MPI'da CAR ve iskemi varlığı arasındaki ilişkiyi araştırmayı amaçladık.
YÖNTEM ve GEREÇLER: Ekim 2017 ve Haziran 2019 tarihleri arasında kardiyoloji polikliniğinden yönlendirilerek SPECT MPI yapılan 2048 hasta retrospektif olarak değerlendirildi. Tarama popülasyonu değerlendirildiğinde serum CRP ve albümin düzeyleri ölçülen ve dışlama ölçütlerini karşılamayan 126 hasta çalışma grubunu oluşturdu. SPECT MPI'da iskemi varlığı ve yokluğuna göre hastalar iki gruba ayrılarak veriler değerlendirildi
BULGULAR: Laboratuvar bulguları açısından değerlendirildiğinde iskemi bulunan grupta CRP ve CAR anlamlı olarak daha yüksek iken, bu grupta serum albümini anlamlı olarak daha düşük bulundu (her biri için P <0.05). Çok değişkenli analizde, iskemi varlığının bağımsız prediktörleri hipertansiyon ve CAR idi (CAR; OR: 5.720,% 95 CI: 2.697-12.133, P <0.001). İskemi varlığı için en uygun CAR değeri% 76 hassasiyet ve% 71 özgüllük ile 0.96 olarak bulunmuştur.
TARTIŞMA ve SONUÇ: Çalışmamız miyokard iskemisi ve CAR değerleri arasındaki ilişkiyi araştıran ilk çalışma olarak değerlidir. Miyokard perfüzyon sintigrafisi öncesi bakılan CAR değerleri iskemi için prediktör olarak bulundu.

INTRODUCTION: Several studies have shown the connection between coronary artery disease (CAD) and inflammatory parameters. Nevertheless, there is not enough evidence regarding the role of hs-C-reactive protein (CRP) to albumin ratio (CAR) in patients with presence of ischemia on gated SPECT myocardial perfusion imaging (MPI). This study aimed to investigate the relationship between CAR and presence of ischemia on gated SPECT MPI.
METHODS: A total of 2048 patients referred for gated SPECT MPI from a cardiology outpatient clinic between October 2017 and June 2019 were evaluated retrospectively. After applying exclusion criteria and measuring serum CRP and albumin levels, 126 patients were included in the study. The subjects were classified into different groups according to the absence and presence of ischemia on gated SPECT MPI.
RESULTS: In terms of laboratory findings, hs-CRP and CAR were higher in the ischemia group, while the serum albumin was lower in ischemia group with significant statistical values (P<0.05 for each). The independent predictors of presence of ischemia in multivariate analysis were hypertension and CAR (CAR; OR: 5.720, 95% CI: 2.697–12.133, P<0.001). The optimal value of CAR for presence of ischemia was found to be 0.96 with a 76% sensitivity and 71% specificity.
DISCUSSION AND CONCLUSION: CAR values were found as a predictor for ischemia before myocardial perfusion scintigraphy.

INTRODUCTION: Ga-67 imaging is affected by collimator penetration and scatter components due to high energy gamma-ray emissions. The characterization of penetration and scatter distribution is important for optimization of collimator design and development of correction method. This study proposes to compare the image quality that can be achieved by three collimators.
METHODS: The simulation was carried out for LEHR(Low Energy High Resolution), ME(Meduim Energy) and HE(High Energy) collimators for Ga-67 point source placed at 12 cm from the detector surface using Monte Carlo SIMIND simulation code. Their spectrums, point spread functions and also geometric, penetration, scattering and x-rays curves were drawn and analyzed. FWHM (full width at half maximum) and FWTM(full width at tenth maximum) were also investigated.
RESULTS: The geometric, penetration, and scatter within 10% for LEHR were 34,46 %, 33,52%, 17,29% and 14,72% respectively. Similarly, geometric, penetration, scatter and x-rays within 10% for ME and HE were 83,06%, 10,25%, 6,69% and 0% and 81,44%, 11,51%, 7,05% and 0%. The tradeoff between spatial resolution and sensitivity is achieved by using the ME collimator, with the 185 photopeak of Ga-67.
DISCUSSION AND CONCLUSION: The Monte Carlo simulation results can be used for optimal collimator design and development of new correction method in Ga-67 imaging.

INTRODUCTION: Absorbed dose to red marrow ("D" _"rm" ) can be calculated using blood dosimetry. However, completed blood method is laborious and invasive. Therefore, image-based dosimetry is the method of choice. Nonetheless, commercial software is expensive. The goal of this work was to develop a simplified Excel spreadsheet for image-based radioiodine red marrow dosimetry.
METHODS: The serial whole-body images (acquired at 2, 6, 24, 48, and 72 hours) of 29 patients from the routine pre-therapeutic dosimetry protocol were retrospectively reanalyzed. In routine, the commercial OLINDA/EXM image-based dosimetry software was used to calculate the whole-body time-integrated activity coefficient (〖"TIAC" 〗_"WB" ) and "D" _"rm" (in term of absorbed dose coefficient (d_rm)). For a simplified Excel spreadsheet, the whole-body count was obtained from the vendor supplied software. Then, the 〖"TIAC" 〗_"WB" was computed by fitting time-activity curve using Excel function. S-factor was taken from other publications and scaled according to the patient-specific mass. A comparison of the 〖"TIAC" 〗_"WB" and d_rm from two methods was analyzed using a non-inferiority test based on a paired t-test or the Wilcoxon signed rank test.
RESULTS: The 〖"TIAC" 〗_"WB" showed no significant difference between two methods (p-value 0.243 with a paired t-test). The calculated "d" _"rm" " " from a simplified Excel spreadsheet was assumed to be statistically non-inferior to the commercial OLINDA/EXM image-based dosimetry software with the non-inferiority margin of 0.02 (p-value < 0.05 with the Wilcoxon signed rank test).
DISCUSSION AND CONCLUSION: The dose assessment from a simplified Excel spreadsheet is feasible and relatively low cost compared to the commercial OLINDA/EXM image-based dosimetry software

Paget, aşırı ve anormal kemik yapımı ve yıkımı ile karakterize kronik, iyi huylu bir kemik hastalığıdır. Monostotik Paget hastalığı, sadece vakaların yüzde yirmisini oluşturmakla kalmaz; Mickey Mouse bulgusu olan, vertebra tutulumu ile giden monostotik formu daha da nadirdir. Sunduğumuz vakada, ikinci lumbar vertebrada metastaz şüphesi ile araştırılan hastada; kemik sintigrafisinde Mickey Mouse işareti görülmesi üzerine Paget hastalığı tanısı kondu ve tanı biyopsiyle doğrulandı. Bu olguda görülmektedir ki; kemik sintigrafisi tanıya olumlu katkıda bulunur ve belirli belirti ve paternler görülmesi sayesinde gereksiz biyopsileri önleyebilir.

Paget is a chronic benign bone disease characterised by excessive and abnormal bone remodelling. Not only monostotic Paget’s disease accounts for twenty percent of the cases; but also monostotic form involving the vertebra with the Mickey Mouse sign is even rarer. Herein, we report a case with suspected bony metastasis in the second lumbar vertebra, and diagnosed as Paget’s disease; because of Mickey Mouse sign on bone scintigraphy and the diagnosis was confirmed by biopsy. Thus the bone scintigraphy makes a positive contribution to the diagnosis, and may avoid unnecessary biopsy in cases with specific signs and patterns.

Hepatoselüler karsinom (HSK)’unun ilk belirtisi olarak, kemik metastazının neden olduğu spinal kord kompresyonu ile başvuran 69 yaşında bir erkek hastayı tanımladık. Başlangıç evreleme için, hastaya F18-FDG PET/BT görüntüleme yapıldı. Görüntüleme çok sayıda ekspansil osteolitik kemik lezyonlarında hafif F18-FDG tutulumu gösterdi ve düşük doz BT'deki karaciğer lezyonunda kayda değer atipik F18-FDG tutulumu göstermedi. HSK da dahil olmak üzere çeşitli tümörlerde potansiyel bir biyolojik marker olduğu bildirilen PSMA ekspresyonunu değerlendirmek için ek bir PET/BT görüntüleme yapıldı. Hem metastatik kemik lezyonlarında hem de primer karaciğer lezyonunda/tümöründe yüksek PSMA tutulumu Ga68-PSMA PET/BT ile saptandı.

We describe a 69-year-old male presented with spinal cord compression due to bone metastases as first manifestation of hepatocellular carcinoma (HCC). For initial staging, the patient underwent 18F-FDG PET/CT imaging. The scan demonstrated mild 18F-FDG uptake in the multiple expansile osteolytic bone lesions, and no remarkable atypical 18F-FDG uptake in the primary liver lesion on low-doses CT. An additional PET/CT scan was performed to evaluate the PSMA expression which recently reported to be a potential biologic marker in a variety of tumors including HCC. High PSMA uptake both in metastatic bone lesions and in primary liver lesion/tumour were detected by 68Ga-PSMA PET/CT.

65 years old female, known diabetic and hypertensive underwent 99mTc-methylene diphosphonate (Tc-99m MDP) bone scan with Single Photon Emission Computed Tomography (SPECT-CT) for shoulder pain. Initially she was treated with breast cancer and later for hepatocellular carcinoma. SPECT-CT showed MDP non avid scattered pulmonary ground glass opacities (GGO) bilaterally along with rounded nodular densities. Another 56 years old newly diagnosed right breast invasive ductal carcinoma had bone scan with SPECT-CT which revealed bilateral pulmonary infiltrates. Both of these patients later tested positive for COVID-19. Therefore, Nuclear Physicians should be watchful of COVID-19 related findings on SPECT-CT thorax as this becomes the new normal for them.