Search

Aim: The prostate bed is one of the common sites of early recurrence of prostate cancer. The currently used PSMA ligands ( 68 Ga-PSMA-11 and 99m Tc-PSMA) undergo early urinary clearance resulting in interfering physiological activity within and surrounding the prostate. This can result in sites of cancer recurrence being obscured. 18 F-PSMA-1007 has an advantage of delayed urinary clearance thus the prostate region is reviewed without any interfering physiological activity. The aim of this study was to determine the diagnostic performance of 18 F-PSMA-1007 PET/CT in patients with early biochemical recurrence after definitive therapy., Methods: Forty-six Prostate cancer (mean age 66.7±7.5, range 48-87 years) presenting with biochemical recurrence (median PSA 1.6ng/ml, range 0.1-10.0) underwent non-contrast-enhanced 18 F-PSMA-1007 PET/CT. PET/CT findings were evaluated qualitatively and semiquantitatively (SUVmax) and compared to the results of histology, Gleason grade, and conventional imaging., Results: Twenty-four of the 46 (52.2%) patients demonstrated a site of recurrence on 18 F-PSMA-1007 PET/CT. Oligometastatic disease was detected in 15 (32.6%) of these patients. Of these 10 (37.5%) demonstrated intra-prostatic recurrence, lymph node disease was noted in 11 (45.8%) whilst two patients demonstrated skeletal metastases. The detection rates for PSA levels 0-<0.5, 0.5-<1, 1-2, >2 were 31.3%, 33.3%, 55.6% and 72.2% respectively. 7 (29.2%) of the positive patients had been described as negative or equivocal on conventional imaging. An optimal PSA cut-off level of 1.3ng/ml was found., Conclusion: 18 F-PSMA-1007 demonstrated good diagnostic performance detecting sites of recurrence. Its ability to detect sites of recurrence in the setting of early biochemical recurrence will have a significant impact on patient management., Competing Interests: The authors declare that they have no conflict of interest., (Thieme. All rights reserved.)

Biochemical recurrence (BCR) is a clinical challenge in prostate cancer (PCa) patients, as recurrence localization guides subsequent therapies. The use of PET with prostate-specific membrane antigen (PSMA) provides better accuracy than conventional imaging practice. This prospective, multicenter, international study was performed to evaluate the diagnostic performance and clinical impact of PSMA PET/CT for evaluating BCR in PCa patients in a worldwide scenario. Methods: Patients were recruited from 17 centers in 15 countries. Inclusion criteria were histopathologically proven prostate adenocarcinoma, previous primary treatment, clinically established BCR, and negative conventional imaging (CT plus bone scintigraphy) and MRI results for patients with PSA levels of 4-10 ng/mL. All patients underwent PET/CT scanning with 68 Ga-PSMA-11. Images and data were centrally reviewed. Multivariate logistic regression analysis was applied to identify the independent predictors of PSMA-positive results. Variables were selected for this regression model on the basis of significant associations in the univariate analysis and previous clinical knowledge: Gleason score, the PSA level at the time of the PET scan, PSA doubling time, and primary treatment strategy. All patients were monitored for a minimum of 6 mo. Results: From a total of 1,004 patients, 77.7% were treated initially with radical prostatectomy and 22.3% were treated with radiotherapy. Overall, 65.1% had positive PSMA PET/CT results. PSMA PET/CT positivity was correlated with the Gleason score, PSA level at the time of the PET scan, PSA doubling time, and radiotherapy as the primary treatment ( P < 0.001). Treatment was modified on the basis of PSMA PET/CT results in 56.8% of patients. PSMA PET/CT positivity rates were consistent and not statistically different among countries with different incomes. Conclusion: This multicenter, international, prospective trial of PSMA PET/CT confirmed its capability for detecting local and metastatic recurrence in most PCa patients in the setting of BCR. PSMA PET/CT positivity was correlated with the Gleason score, PSA level at the time of the PET scan, PSA doubling time, and radiotherapy as the primary treatment. PSMA PET/CT results led to changes in therapeutic management in more than half of the cohort. The study demonstrated the reliability and worldwide feasibility of PSMA PET/CT in the workup of PCa patients with BCR., (© 2022 by the Society of Nuclear Medicine and Molecular Imaging.)

Objectives: We aimed to describe the clinical characteristics and the response to radioactive iodine (RAI) treatment of immune reconstitution inflammatory syndrome-associated Graves disease (IRIS-GD) in comparison to Graves disease (GD) seen in HIV-uninfected patients., Methods: We retrospectively reviewed the medical records of patients treated with RAI for GD. We obtained clinical, biochemical and HIV-related information of patients from their medical records. We compared patient characteristics and response to RAI treatment between patients with IRIS-GD and GD seen in HIV-uninfected patients., Results: A total of 253 GD patients, including 51 patients with IRIS-GD, were included. Among IRIS-GD patients, CD4 cell nadir was 66 cells/µL (range: 37-103) with a peak HIV viral load of 60 900 copies/mL (range: 36 542-64 500). At the time of diagnosis of IRIS-GD, all patients had a completely suppressed HIV viraemia with a CD4 cell count of 729 cells/µL (range: 350-1279). The median interval between the commencement of HIV treatment and the onset of GD was 63 months. At 3 months follow-up, the proportion of patients with IRIS-GD achieving a successful RAI treatment outcome (euthyroid/hypothyroid state) was lower than that of HIV-uninfected patients (35.3% vs. 63.4%, respectively; p < 0.001). The response rate remained lower (60.8%) among patients with IRIS GD than among HIV-uninfected GD patients (80.2%, p = 0.004) at 6 months follow-up. After correcting for differences in age, gender and pre-treatment thyroid-stimulating hormone level, there was no significant difference in RAI treatment response between the two groups., Conclusions: After correcting for possible confounders, the response to RAI treatment was not different between patients with IRIS-GD and GD in HIV-uninfected patients., (© 2021 British HIV Association.)

Objective: Accurate early assessment of biochemical recurrence is essential in determining the correct treatment plan for patients with prostate cancer. Gallium-68-prostate-specific membrane antigen-11 ( 68 Ga-PSMA-11) targeting PSMA has been at the forefront of imaging in biochemical recurrence however the emergence of fluorine-18 ( 18 F)-PSMA-1007 may prove to be advantageous over the 68 Ga-PSMA-11 molecule due to its physical and physiologic al attributes. The aim of our study was to assess the diagnostic performance of 18 F-PSMA-1007 as compared to that of 68 Ga-PSMA-11 in the same patients who presented with biochemical recurrence., Material and Methods: Twenty-one patients with biochemical recurrence prostate cancer were prospectively enrolled into the study. Fluorine-18-PSMA-1007 positron emission tomography/computed tomography (PET/CT) was performed on the same patient after 68 Ga-PSMA-11 PET/CT had been performed. Recurrence diagnosed on each of these studies was compared against a final diagnosis based on clinical follow-up and histological correlation where available., Results: Gallium-68-PSMA-11 identified fifteen (71,4%) patients as being negative for recurrence whilst five (23.8%) were identified as positive and one (4.8%) as uncertain. In comparison 18 F-PSMA-1007 identified eight (38.1%) as being positive with thirteen (61.9%) patients' scans identified as negative for recurrence. No scans were classified as uncertain for the 18 F-PSMA-1007 group. Fluorine-18-PSMA-1007 identified 8 lesions as positive for disease recurrence whilst only 6 lesions were identified on 68 Ga-PSMA-11. Of the 8 patients identified as having recurrence on 18 F-PSMA-1007 4 of those demonstrated local prostatic recurrence. The rest demonstrated local nodal recurrence and skeletal metastases. Fluorine-18-PSMA-1007 demonstrated a sensitivity, specificity, positive and negative predictive value of 88.9%, 100%, 100%, and 92.3% respectively whilst 68 Ga-PSMA-11 demonstrated a sensitivity, specificity, positive and negative predictive value of 44.4%, 83.3%, 80%, and 66.6%, respectively., Conclusion: In our pilot study 18 F-PSMA-1007 was able to detect more sites of recurrence as compared to 68 Ga-PSMA-11 which were mainly within the prostate and surrounding pelvic structures.

Imaging plays a vital role in detecting the recurrence of prostate cancer (PCa) to guide the choice of salvage therapy. Gallium-68 prostate-specific membrane antigen positron-emission tomography/computed tomography ( 68 Ga-PSMA-11 PET/CT) is useful for detecting PCa recurrence. We assessed the pattern of PCa recurrence stratified by serum prostate-specific antigen level and type of primary local treatment in men with biochemical recurrence (BCR) after primary local therapy with radical prostatectomy or external beam radiotherapy (EBRT) using 68 Ga-PSMA-11 PET/CT. We reviewed patients imaged with 68 Ga-PSMA-11 PET/CT for the localization of the site of PCa recurrence. We determined the site and number of lesions due to PCa recurrence at different PSA levels. A total of 247 men (mean age of 65.72 ± 7.51 years and median PSA of 2.70 ng/mL (IQR = 0.78-5.80)) were included. 68 Ga-PSMA-11 PET/CT detected the site of recurrence in 81.4% of patients with a median number of lesions per patient of 1 (range = 1-5). 68 Ga-PSMA-11 PET/CT positivity was 43.6%, 75.7%, 83.3%, 90.0%, and 95.8% at PSA levels of <0.5, 0.5-1.0., 1.1-2.0, 2.1-5.0, and 5.0-10.0, respectively. The most common site of recurrence was in the prostate gland/bed at all PSA levels. Pelvic, extra-pelvic, and combined pelvic and extra-pelvic sites of recurrence were seen in 118, 50, and 33 patients, respectively. The risk of extra-pelvic recurrence increases with rising PSA levels. 68 Ga-PSMA-11 PET/CT has a high lesion detection rate for biochemical recurrence of PCa in patients previously treated with primary local therapy.

Prostate cancer (PCa) causes significant morbidity and mortality in men globally. While localized PCa may be managed with curative intent by surgery and/or radiation therapy, the management of advanced hormone resistant metastatic disease (mCRPC) is more challenging. Theranostics is a principle based on the ability to use an organ specific ligand and label it to both a diagnostic and a therapeutic agent. The overexpression of prostate specific membrane antigen (PSMA) on prostate cancer cells creates a unique opportunity for development of targeted radionuclide therapy. The use of both beta and alpha emitting particles has shown great success. Several clinical trials have been initiated assessing the efficacy and safety profile of these radionuclide agents. The results are encouraging with PSMA directed radioligand therapy performing well in patients who have exhausted all other standard treatment options. Future studies need to assess the timing of introduction of these radionuclide therapies in the management schema of mCRPC. Drugs or therapies are not without side effects and targeted radionuclide therapies presents a new set of toxicities including xerostomia and myelosuppression. New therapeutic strategies are being explored to improve outcomes while keeping toxicities to a minimum. This review aims to look at the various PSMA labelled tracers that form part of the theragnostic approach and subsequently delve into the progress made in the area of radionuclide therapy.

Background: The cardiovascular committee of the European Association of Nuclear Medicine (EANM) recently published recommendations on imaging conditions to be observed during 18 F-FDG PET imaging of vascular inflammation. This study aimed to evaluate the impact of applying these optimized imaging conditions on PET quantification of arterial 18 F-FDG uptake., Methods and Results: Fifty-seven patients were prospectively recruited to undergo an early 18 F-FDG PET/CT imaging at 60 minutes and repeat delayed imaging at ≥ 120 minutes post tracer injection. Routine oncologic 18 F-FDG PET protocol was observed for early imaging, while delayed imaging parameters were optimized for vascular inflammation imaging as recommended by the EANM. Aortic SUVmax of the ascending aorta and SUVmean from the lumen of the superior vena cava (SVC SUVmean) were obtained on early and delayed imaging. Target-to-background ratio (TBR) was obtained for the early and delayed imaging. Aortic SUVmax increased by a mean of 70%, while SVC SUVmean decreased by a mean of 52% between early and delayed imaging (P < 0.001). TBR increased by 122% following delayed imaging. TBR increased, while SVC SUVmean declined across all time-points from 120 to > 180 minutes. Aortic SUVmax significantly increased at imaging time-points between 120 and 180 minutes. No significant improvement in aortic SUVmax was seen at imaging time-points beyond 180 minutes., Conclusions: 18 F-FDG PET imaging conditions optimized for vascular inflammation imaging lead to an improved quantification through an increase in the quantified vascular tracer uptake and decrease in blood-pool background activity., (© 2019. American Society of Nuclear Cardiology.)

Purpose: The aim of this study was to assess the impact of 18F-FDG PET/CT metabolic parameters obtained at initial staging of vulva carcinoma on survival in women with and without HIV infection., Patients and Methods: 18F-FDG PET/CT images of women with vulva cancer who are planned for definitive therapy were analyzed. SUVmax, SUVmean, MTV, and total lesion glycolysis (TLG) as well as whole-body MTV and whole-body TLG were computed., Results: Twenty-five women were included with a mean age of 43.44 ± 10.32. The majority of the patients were HIV infected with a median CD4 count of 444.00 cells/mm3. The HIV-infected women are younger at diagnosis than their HIV-uninfected counterparts. All patients presented with inguinofemoral lymph node involvement, whereas half the patients had pelvic nodal metastasis. All the patients with distant visceral or skeletal metastasis were HIV infected. The lungs were the most common site of distant metastasis. When comparing the SUVmax, SUVmean, MTV, TLG, wbMTV, and wbTLG between HIV-infected and HIV-uninfected patients, we did not find statistical differences. Twelve patients (48%) were upstaged to metastatic disease. Seven patients had died at the time of analysis. The wbMTV and wbTLG were significantly higher in nonsurvivors than survivors., Conclusions: 18F-FDG PET/CT improves initial staging of squamous cell carcinoma among women with and without HIV infection. The whole-body tumor burden assessed by 18F-FDG PET metabolic metrics did not differ between HIV-infected and HIV-uninfected women. A higher whole-burden tumor burden is associated with a higher risk of mortality among women with vulva cancer., Competing Interests: Conflicts of interest and sources of funding: none declared., (Copyright © 2021 Wolters Kluwer Health, Inc. All rights reserved.)

Objective:  To assess the patterns of recurrence of vulva cancer on 18 F-FDG PET/CT and to compare the 18 F-FDG PET metabolic metrics in patients with and without Human Immunodeficiency Virus (HIV)., Methods:  Maximum standardized uptake value (SUV max ), mean standardized uptake value (SUV mean ), metabolic tumour volume (MTV and total lesion glycolysis (TLG) were obtained on Flourine-18 Fluorodeoxyglucose Positron Emission Tomography/Computed Tomography ( 18 F-FDG PET/CT) images of women referred with suspected or confirmed vulva cancer recurrence. We compared HIV-infected and HIV-uninfected patients regarding pattern disease recurrence, age at diagnosis, and the PET-derived metabolic indices., Results:  We analyzed 33 patients with a mean age 50.76 ± 15.78 including 21 HIV-infected women. The majority of patients (94 %) had squamous cell carcinoma and 84.85 % were Blacks. Of the HIV-infected individuals, the median CD4 count was 526.0 cells/mm3 (IQR: 379.0-729.0). HIV infected patients were younger than the HIV uninfected at the time of diagnosis: 40.50 ± 8.87 vs 66.54 ± 9.71 respectively, p < 0.001. We found a local (vulvar) recurrence rate of 75.8 %. Nodal pelvic recurrences were higher in the HIV-infected patients than in the HIV uninfected patients (70 % vs 30 %, p = 0.027). Three patients had distant metastasis and all three were HIV-infected. There was a higher whole-body MTV and TLG among HIV-infected women compared with HIV-uninfected women, 103.39 vs 17.58 and 852.64 vs 101.79, respectively (p < 0.05 for both)., Conclusion:  HIV-infected women are diagnosed with vulva cancer at a younger age. HIV-infected patients had a higher rate of pelvic lymph node recurrence. There is a higher tumor burden at vulva cancer recurrence among women with HIV infection., Competing Interests: The authors declare that they have no conflict of interest., (Thieme. All rights reserved.)

To evaluate arterial fluorodeoxyglucose (FDG) uptake as a marker of arterial inflammation in multiple vascular beds in patients treated with anthracycline-based chemotherapy for Hodgkin lymphoma (HL).We used maximum standardized uptake value (SUVmax) and target-to-background ratio (TBR) to quantify arterial FDG uptake in the carotid artery, ascending aorta, abdominal aorta, and femoral artery obtained on positron emission tomography/computed tomography (PET/CT) imaging performed at baseline before chemotherapy and after completion of chemotherapy in patients with HL treated with an anthracycline-containing regimen. We compared the SUVmax and TBR obtained at baseline with that obtained post-chemotherapy for each arterial bed to evaluate the effect of anthracycline-based chemotherapy. We evaluated the effect of cardiovascular risk factors such as human immunodeficiency virus (HIV) infection, smoking, hypertension, and diabetes on the changes in SUVmax and TBR seen in the different arterial beds after anthracycline-based chemotherapy.Fifty-two patients were included with a mean age of 34.56 ± 10.19 years. There were 33 males, and 18 patients were HIV-infected. The mean interval between completion of chemotherapy and follow-up flourine-18 fluorodeoxyglucose positron emission tomography/computed tomography (FDG PET/CT) scan was 65 weeks. We found no significant difference in arterial FDG uptake measured by SUVmax and TBR in all arterial beds between the pre- and post-chemotherapy FDG PET/CT. There was no significant impact of HIV infection, smoking, and hypertension on the changes in arterial FDG uptake following treatment with anthracycline-based chemotherapy.In patients with HL who were treated with anthracycline-based chemotherapy, we found no significant increase in arterial inflammation measured by FDG PET/CT after an average follow-up period of about 65 weeks since completion of chemotherapy.

Cervical cancer is staged clinically using the International Federation of Gynaecology and Obstetrics staging system. Although lymph node status does not form part of the staging, it has important prognostic and potential therapeutic implications. The aim of the study was to evaluate the role of sentinel lymph node (SLN) scintigraphy and 2-[ 18 F]-fluoro-2-deoxy-D-glucose positron emission tomography/computed tomography ( 18 F-FDG PET/CT) in detecting lymph node metastases in patients with early-stage cervical cancer. Thirty-six patients with early-stage cervical cancer underwent SLN detection during primary operation. Of the 36 patients, 28 patients underwent 18 F-FDG PET/CT before surgery. The 18 F-FDG PET/CT images were analyzed with the histopathological findings as the reference standard. The diagnostic performance of 18 F-FDG PET/CT in the detection of nodal disease was reported in terms of accuracy value. The SLN detection rate was the highest (91.7%) using the combined method (lymphoscintigraphy, intraoperative gamma probe, and blue dye). Seven of the thirty-six patients had lymph node involvement (19.4%), of which five had preoperative 18 F-FDG PET/CT imaging. On overall patient-based analysis, the sensitivity, specificity, positive predictive value, negative predictive value (NPV), and accuracy of 18 F-FDG PET/CT were 40.0%, 78.3%, 28.6%, 85.7%, and 71.4%, respectively. The combination of radiolabeled nanocolloid with blue dye is safe and reliable and allows successful detection of SLNs in patients with early-stage cervical cancer in a population with high prevalence of human immunodeficiency virus. The specificity and NPV of 18 F-FDG PET/CT are high and can be used in conjunction with SLN biopsy., Competing Interests: There are no conflicts of interest., (Copyright: © 2020 World Journal of Nuclear Medicine.)

Microbial culture is the gold standard for determining the effectiveness of tuberculosis treatment. End-of-treatment (EOT) 18 F-FDG PET/CT findings are variable among patients with negative microbial culture results after completing a standard regimen of antituberculous treatment (ATT), with some patients having a complete metabolic response to treatment whereas others have residual metabolic activity (RMA). We herein determine the impact of findings on EOT 18 F-FDG PET/CT on tuberculosis relapse in patients treated with a standard regimen of ATT for drug-sensitive pulmonary tuberculosis (DS-PTB). Methods: Patients who completed a standard regimen of ATT for DS-PTB and were declared cured based on a negative clinical and bacteriologic examination were prospectively recruited to undergo EOT 18 F-FDG PET/CT. Images were assessed for the presence of RMA. Patients were subsequently followed up for 6 mo looking for symptoms of tuberculosis relapse. When new symptoms developed, relapse was confirmed with bacteriologic testing. Repeat 18 F-FDG PET/CT was done in patients who relapsed. Results: Fifty-three patients were included (mean age, 37.81 ± 11.29 y), with 62% being male and 75% HIV-infected. RMA was demonstrated in 33 patients (RMA group), whereas 20 patients had a complete metabolic response to ATT (non-RMA group). There was a higher prevalence of lung cavitation in the RMA group ( P = 0.035). The groups did not significantly differ in age, sex, presence of HIV infection, body mass index, or hemoglobin level ( P > 0.05). On follow-up, no patients in the non-RMA group developed tuberculosis relapse. Three patients in the RMA group developed relapse. All patients who developed tuberculosis relapse had bilateral disease with lung cavitation. Conclusion: A negative EOT 18 F-FDG PET/CT result is protective against tuberculosis relapse. Nine percent of patients with RMA after ATT may experience tuberculosis relapse within 6 mo of completing ATT. Bilateral disease with lung cavitation is prevalent among patients with tuberculosis relapse., (© 2020 by the Society of Nuclear Medicine and Molecular Imaging.)

Metastatic prostate carcinoma overexpresses prostate-specific membrane antigen (PSMA), making this antigen a suitable target for radioligand therapy of the disease. Here we report on our experience with a series of 73 castration-resistant prostate carcinoma patients treated with 225 Ac-PSMA-617, identifying variables predictive for overall survival (OS) and progression-free survival (PFS) after 225 Ac-PSMA-617 treatment. Methods: 225 Ac-PSMA-617 was administered to patients who had metastatic castration-resistant prostate carcinoma and who had exhausted available therapy options for their disease. Full blood count, glomerular filtration rate, and liver function test were obtained at baseline and on follow-up for evaluation of toxicity. 68 Ga-PSMA PET/CT was obtained at baseline, before every treatment cycle, and on follow-up for selection of patients for treatment, to determine the activity of the treatment agent to be administered, and for response assessment. Serial prostate-specific antigen (PSA) was obtained for PSA response assessment. Results: Seventy-three men (mean age, 69 y; range, 45-85 y) with metastatic castration-resistant prostate carcinoma were treated with 210 cycles of 225 Ac-PSMA-617. In 70% of patients, a PSA decline of greater than or equal to 50% was obtained; 82% of patients had any PSA decline. In 29% of patients, all lesions on 68 Ga-PSMA PET resolved in response to treatment. During follow-up, 23 patients experienced disease progression, whereas 13 patients died from their disease. The estimated median PFS and OS were 15.2 mo (95% CI, 13.1-17.4) and 18 mo (95% CI, 16.2-19.9), respectively. In univariate analyses, factors such as baseline PSA, any PSA decline, PSA decline of greater than or equal to 50%, prior chemotherapy, prior radiation therapy, and baseline hemoglobin level were associated with longer PFS and OS (all P s < 0.05). In multivariate analyses, there was a negative association between prior 177 Lu-PSMA therapy and PFS, and a positive association between PSA decline of greater or equal to 50% and PFS. Only a PSA decline of greater than or equal to 50% remained significantly associated with OS on multivariate analyses. Xerostomia was seen in 85% of patients but was not severe enough to warrant discontinuing treatment. Anemia was seen in 27 patients; no patients had grade IV bone marrow toxicity. Renal failure of grade III or IV was seen in 5 patients with baseline renal impairment. Conclusion: In this study, a PSA decline of greater than or equal to 50% after treatment with 225 Ac-PSMA-617 was proven by multivariate analyses to be significantly associated with OS and PFS. Furthermore, previous 177 Lu-PSMA treatment was negatively associated with PFS in both univariate and multivariate analyses., (© 2020 by the Society of Nuclear Medicine and Molecular Imaging.)

We report a case of a 47-year-old female known with metastatic papillary thyroid cancer. Her treatment history included total thyroidectomy and 3 previous radio ablations with a cumulative dose of 950 mCi of 131 I. On follow-up, her thyroglobulin levels had demonstrated a rising trend (from 3789.0 to 4240.0 ug/L) despite a 123 I whole-body scan demonstrating a reduction in tracer avid lesions. She was suspected of having radio-resistant disease. The patient underwent both 18 F-FDG and 68 Ga-PSMA PET/CT imaging with both scans demonstrating congruent lesions however with far greater intensity on the 68 Ga-PSMA study., Competing Interests: Conflict of InterestThabo Lengana, Ismaheel O. Lawal, Kgomotso Mokoala, Mariza Vorster, and Mike M. Sathekge declare that they have no conflict of interest., (© Korean Society of Nuclear Medicine 2019.)

Background: HIV infection is associated with the risk of development of atherosclerosis at a younger age. We compared arterial inflammation in HIV-infected and HIV-uninfected patients with otherwise low-risk factors for cardiovascular disease (CVD) using FDG PET/CT., Methods: 242 patients aged 18-40 years with low-risk factors for CVD consisting of 121 HIV-infected patients and 121 HIV-uninfected age- and gender-matched controls were studied, mean age = 34.95 ± 5.46 years. We calculated and compared the target-to-background ratio of FDG uptake in ascending aorta of HIV-infected and non-infected patients., Results: Median CD4 count and viral load were 375.5 cells/mm 3 (range 2-1094) and 6391.00 copies/mL (range 24-1,348,622), respectively. There was slightly higher but significant overlap in the TBR between HIV-infected group compared with control (1.22, 0.87-2.02 vs. 1.12, 0.38-1.40, P < 0.001). TBR was neither affected by CD4 count levels nor the presence or absence of detectable viremia. We also found no significant difference in TBR between male and female patients with HIV infection. We found a weak positive correlation between TBR and CD4 count, TBR and duration of HIV infection, and a very weak negative correlation between TBR and viral load. There was no significant difference in TBR between patients on HAART and those not yet commenced on therapy., Conclusion: Marginally higher TBR with a significant overlap exist in HIV-infected patients compared with control. Arterial F-18 FDG uptake is not affected by the CD 4 count, viral load, gender, or duration of HIV infection.

Objectives: To determine the impact of FDG-PET/CT in the initial staging of cervical cancer among women with and without HIV and to determine the abilities of FDG-PET/CT metabolic parameters in predicting the presence of distant metastasis., Methods: We reviewed the FDG-PET/CT images of women with FIGO stage IB2 to IVA carcinoma of the cervix. We compared the FIGO stage before and after FDG-PET/CT. Maximum and mean standardized uptake values (SUVmax and SUVmean), metabolic tumor volume (MTV) and total lesion glycolysis (TLG) of the primary lesion were determined. We compared these parameters between the HIV-infected and uninfected woman and also determined their abilities to predict the presence of distant metastasis., Results: 126 women, mean age 48.05 ± 11.80 years were studied. Seventy-three patients were HIV-infected. The disease was upstaged in 65 patients, 32 of which were upstaged to stage IVB. HIV-infected women were younger (43.36 ± 8.03 years versus 54.51 ± 13.12, p<0.001) and had more advanced disease (p = 0.022) compared with HIV-uninfected. In a univariate logistic regression adjusted for the FIGO stage of the disease, there were significant associations between MTV and TLG of the primary tumor and distant metastasis. SUVmax, SUVmean, MTV and TLG performed well in predicting the presence of distant metastasis with areas under the curves (AUCs) of 0.63, 0.66, 0.80 and 0.77 respectively. These performances improved after adjustment for the FIGO stage of the disease with AUCs of 0.80, 0.79, 0.84 and 0.82 for SUVmax, SUVmean, MTV and TLG respectively., Conclusion: Inclusion of 18F-FDG-PET/CT in the pre-therapy assessment of cervical cancer improves the accuracy of staging in about half of the patients. The metabolic parameters of the primary tumor perform well in predicting the presence of distant metastases., Competing Interests: The authors have declared that no competing interests exist.

Objective: To evaluate the role of fluorine-18-fluorodeoxyglucose positron emission tomography/computed tomography ( 18 F-FDG PET/CT) in identifying the cause of fever of unknown origin (FUO) in patients on renal replacement therapy (RRT) for end-stage renal disease (ESRD)., Subjects and Methods: We retrospectively reviewed the 18 F-FDG PET/CT scans of 46 patients with a mean age of 39.28±12.50 years on RRT for ESRD. All patients with abnormal scans had histopathologic examination and microbial cultures of tissue samples from areas with increased standardized uptake value maximum (SUVmax) suggesting the cause of FUO in the 18 F-FDG PET/CT scan. Fluorine-18-FDG PET/CT was considered helpful if it led to the diagnosis of the cause of FUO after histopathologic and microbiologic examinations., Results: Fluorine-18-FDG PET/CT was helpful in identifying the cause of FUO in 22/46 patients (47.83%). Infection was the cause of fever in all these 22 patients. C-reactive protein (CRP) (P=0.003) and procalcitonin levels (P=0.021) were higher in patients with helpful 18 F-FDG PET/CT. No significant difference was found in blood sugar levels and leucocytes counts between patients with helpful 18 F-FDG PET/CT outcome and those without. By multiple regression analysis, the odds of a helpful 18 F-FDG PET/CT increased with every unit increase in CRP level (OR: 1.009; 95% CI: 1.003-1.016; P=0.005)., Conclusion: About half of the 18 F-FDG-PET/CT scans (22/46) identified the cause of FUO in patients on RRT for ESRD. The clinical utility of 18 F-FDG PET/CT in this group of patients is comparable to its average performance in the unselected patients' population evaluated for FUO. A higher CRP level was predictive of a positive 18 F-FDG PET/CT outcome.

Background: A remarkable therapeutic efficacy has been demonstrated with 225 Ac-prostate-specific membrane antigen (PSMA)-617 in heavily pre-treated metastatic castration-resistant prostate cancer (mCRPC) patients. We report our experience with 225 Ac-PSMA-617 therapy in chemotherapy-naïve patients with advanced metastatic prostate carcinoma., Methods: Seventeen patients with advanced prostate cancer were selected for treatment with 225 Ac-PSMA-617 in 2-month intervals, with initial activity of 8 MBq, then de-escalation to 7 MBq, 6 MBq or 4 MBq in cases of good response. In one patient, activity was escalated to 13 MBq in the third cycle. Fourteen patients had three treatment cycles administered, while in three patients treatment was discontinued after two cycles due to good response. Six out of 17 patients received additional treatments after the third cycle. Prostate-specific antigen (PSA) was measured every 4 weeks for PSA response assessment. 68 Ga-PSMA-PET/CT was used for functional response assessment before each subsequent treatment cycle. Serial full blood count, renal function test, and liver function were obtained to determine treatment-related side effects., Results: Good antitumor activity assessed by serum PSA level and 68 Ga-PSMA-PET/CT was seen in 16/17 patients. In 14/17 patients, PSA decline ≥90% was seen after treatment, including seven patients with undetectable serum PSA following two (2/7) or three cycles (5/7) cycles of 225 Ac-PSMA-617. Fifteen of 17 patients had a > 50% decline in lesions avidity for tracer on 68 Ga-PSMA-PET/CT including 11 patients with complete resolution (PET-negative and either stable sclerosis on CT for bone or resolution of lymph node metastases) of all metastatic lesions. Grade 1/2 xerostomia was seen in all patients, and none was severe enough to lead to discontinuation of treatment. One patient had with extensive bone marrow metastases and a background anemia developed a grade 3 anemia while another patient with solitary kidney and pre-treatment grade 3 renal failure developed grade 4 renal toxicity following treatment. The group presented with significant palliation of bone pain and reduced toxicity to salivary glands due to de-escalation., Conclusions: 225 Ac-PSMA-617 RLT of chemotherapy-naïve patients with advanced metastatic prostate carcinoma led to a ≥ 90% decline in serum PSA in 82% of patients including 41% of patients with undetectable serum PSA who remained in remission 12 months after therapy. The remarkable therapeutic efficacy reported in this study could be achieved with reduced toxicity to salivary glands due to de-escalation of administered activities in subsequent treatment cycles. This necessitates further exploration for informing clinical practice and clinical trial design.

Objectives: Baseline metabolic metrics on fluorine-18-fluorodeoxyglucose PET (F-FDG PET) have prognostic value in Hodgkin lymphoma. International Prognostic Score (IPS) is used in the risk stratification of Hodgkin lymphoma. We compared the metabolic indices in HIV-infected and the IPS in HIV-infected and uninfected patients with Hodgkin lymphoma., Patients and Methods: We retrospectively reviewed the data of HIV-infected and HIV-uninfected patients with classic Hodgkin lymphoma who had F-FDG PET for staging and compared the maximum standardized uptake value, mean standardized uptake value, metabolic tumor volume, and total lesion glycolysis between the two groups. We also compared the IPS and other prognostic indicators and correlated them with the metabolic indices in the two groups., Results: We studied 160 patients, which included 57 patients who were infected with HIV. The mean age was 33.84±11.88 years, with 38% (n=61) being female. The median cluster of differentiation 4 count and HIV viral load were 259 cells/mm and 4837.50 copies/ml, respectively. No significant difference in maximum standardized uptake value, mean standardized uptake value, metabolic tumor volume, and total lesion glycolysis between the two groups was found. Among the seven parameters of the IPS, only male sex (HIV-uninfected group higher, P=0.005) and serum albumin less than 4 g/dl were significantly different. The other parameters were not significantly different between the two groups. Other prognostic indicators including bulky disease, extranodal involvement, and the number of nodal groups involved were not significantly different between the two groups., Conclusion: There was no significant difference in F-FDG metabolic parameters, IPS, and other risk indicators between HIV-infected and HIV-uninfected patients with Hodgkin lymphoma.

Purpose: 68 Ga ligands targeting prostate-specific membrane antigen (PSMA) are rapidly emerging as a significant step forward in the management of prostate cancer. PSMA is a type II transmembrane protein with high expression in prostate carcinoma cells. We prospectively evaluated the use of 68 Ga-PSMA positron emission tomography/computed tomography (PET/CT) in patients with prostate cancer and compared the results to those for technetium-99m ( 99m Tc)-10-metacyloyloxydecyl dihydrogen phosphate (MDP) bone scintigraphy (BS)., Patients and Methods: A total 113 patients with biopsy-proven prostate cancer referred for standard-of-care BS were prospectively enrolled onto this study. 68 Ga-PSMA PET/CT was performed after BS. Metastasis diagnosed on each technique was compared against a final diagnosis based on CT, magnetic resonance imaging, skeletal survey, clinical follow-up, and histologic correlation., Results: Ninety-one bone lesions were interpreted as bone metastases in 25 men undergoing 68 Ga-PSMA PET/CT compared to only 61 lesions in 19 men undergoing 99m Tc-MDP BS. Of the 7 bone scans that missed skeletal metastases, 54% of these missed lesions were due to either marrow or lytic skeletal metastases. The median standardized uptake value in all malignant bone lesions was 13.84. 68 Ga-PSMA PET/CT showed significantly higher sensitivity and accuracy than BS (96.2% vs. 73.1%, and 99.1% vs. 84.1%) for the detection of skeletal lesions. For extraskeletal lesions, 68 Ga-PSMA PET/CT showed an additional 96 unexpected lesions with a median standardized uptake value of 17.6., Conclusion: 68 Ga-PSMA PET/CT is superior to and can potentially replace bone scan in the evaluation for skeletal metastases in the clinical and trial setting because of its ability to detect lytic and bone marrow metastases., (Copyright © 2018 Elsevier Inc. All rights reserved.)

The introduction of 18 F-labeled prostate-specific membrane antigen (PSMA)-targeted PET/CT tracers, first 18 F-DCFPyL (2-(3-{1-carboxy-5-[(6- 18 F-fluoro-pyridine-3-carbonyl)-amino]-pentyl}-ureido)-pentanedioic acid) and more recently 18 F-PSMA-1007 (((3 S, 10 S, 14 S )-1-(4-((( S )-4-carboxy-2-(( S )-4-carboxy-2-(6- 18 F-fluoronicotinamido)butanamido)butanamido)methyl)phenyl)-3-(naphthalen-2-ylmethyl)-1,4,12-trioxo-2,5,11,13-tetraazahexadecane-10,14,16-tricarboxylic acid)), have demonstrated promising results for the diagnostic workup of prostate cancer. This clinical study presents an intraindividual comparison to evaluate tracer-specific characteristics of 18 F-DCFPyL versus 18 F-PSMA-1007. Methods: Twelve prostate cancer patients, drug-naïve or before surgery, received similar activities of about 250 MBq of 18 F-DCFPyL and 18 F-PSMA-1007 48 h apart and were imaged 2 h after injection on the same PET/CT scanner using the same reconstruction algorithm. Normal-organ biodistribution and tumor uptake were quantified using SUV max Results: PSMA-positive lesions were detected in 12 of 12 prostate cancer patients. Both tracers, 18 F-DCFPyL and 18 F-PSMA-1007, detected the same lesions. No statistical significance could be observed when comparing the SUV max of 18 F-DCFPyL and 18 F-PSMA-1007 for local tumor, lymph node metastases, and bone metastases. With regard to normal organs, 18 F-DCFPyL had statistically significant higher uptake in kidneys, urinary bladder, and lacrimal gland. Vice versa, significantly higher uptake of 18 F-PSMA-1007 in muscle, submandibular and sublingual gland, spleen, pancreas, liver, and gallbladder was observed. Conclusion: Excellent imaging quality was achieved with both 18 F-DCFPyL and 18 F-PSMA-1007, resulting in identical clinical findings for the evaluated routine situations. Nonurinary excretion of 18 F-PSMA-1007 might present some advantage with regard to delineation of local recurrence or pelvic lymph node metastasis in selected patients; the lower hepatic background might favor 18 F-DCFPyL in late stages, when rare cases of liver metastases can occur., (© 2018 by the Society of Nuclear Medicine and Molecular Imaging.)

Objective: To compare the diagnostic accuracy of Ga-prostate-specific membrane antigen (PSMA)-HBED-CC PET/computed tomography (CT) imaging for the detection of androgen-dependent recurrent prostate carcinoma (ADPC) in Black South Africans (BSAs) versus White South Africans (WSAs) with increasing serum prostate-specific antigen (PSA) values below or equal to 10 ng/ml., Patients and Methods: A total of 61 patients with ADPC were prospectively included in the study (mean age: 66.7 years): 38 WSAs and 23 BSAs. Ga-PSMA-HBED-CC PET/CT imaging results obtained were related to serum PSA levels and to ethnicity., Results: A total of 41 (67%) patients had a positive Ga-PSMA-HBED-CC scan result. Ga-PSMA-HBED-CC PET/CT positivity was significantly higher in patients with PSA values more than 2 ng/ml [32/38 (84%) patients] when compared with patients with PSA values less than 0.5 ng/ml [6/11 (55%) patients] or PSA values of 0.5-2 ng/ml [3/12 (25%) patients] (P=0.0001). Mean PSA values proved not significantly different in patients presenting with extrapelvic involvement when compared with those with intrapelvic involvement or between patients who presented with bone involvement versus those who did not on Ga-PSMA-HBED-CC PET/CT) (P≥0.147). Age, Gleason-scores, median PSA values, the frequency of a positive scan result, the frequency of bone involvement, and extrapelvic involvement proved similar in WSAs and BSAs (P≥0.417)., Conclusion: Ga-PSMA-HBED-CC PET/CT imaging identified a recurrence in 67% of the patients under study. Higher PSA levels were associated with Ga-PSMA-HBED-CC PET/CT positivity and the detection rate. Imaging results obtained proved similar in BSAs and WSAs, suggesting that the tumor burden and growth rate of ADPC are similar in both races.

Purpose: The incidence of prostate cancer is 60% higher and the mortality rate is two- to three-times greater in black versus white men. We report on differences in 68 Ga-PSMA-11 PET/CT imaging findings in 77 black South-African (BSAs) and 18 white South-African (WSAs) treatment-naïve primary prostate carcinoma (PPC) patients., Methods: 68 Ga-PSMA-11 PET/CT imaging findings were compared to histological, biochemical and morphological imaging data. Patients were grouped into three Gleason grade groups (GG), GG 1 (scores 3 + 3 and 3 + 4), GG2 (scores 4 + 3 and 4 + 4) and GG3 (scores 9 and 10), and the PSA difference among the groups was determined. Inter-racial difference in SUVmax of the primary tumor as well as its correlation with serum PSA were also determined., Results: Ninety-three out of 95 PPC where readily identified on 68 Ga-PSMA-11 PET/CT imaging. Median PPC SUVmax and serum PSA values proved significantly higher (p = 0.033 and p = 0.003) in GG3 patients (median 16.4 and 180 ng/ml) when compared to GG1 patients (median 9.6 and 25.1 ng/ml) or GG2 patients (median 8.8 and 46.2 ng/ml). SUVmax significantly correlated with serum PSA-values (r = 0.377 (p = 0.0001)). Age, frequency of lymph node involvement and distant metastases, and GGs (p ≥ 0.153) were similar in BSAs and WSAs, both median serum PSA-values as well as SUVmax values proved significantly higher in BSAs when compared to WSAs, respectively, 81.6 ng/ml versus 14.5 ng/ml (p = 0.0001) and 11.9 versus 4.38 (p = 0.004). Moreover, Gleason-score normalized median SUVmax values proved 2.5 times higher in BSAs when compared to WSAs (p = 0.005)., Conclusion: SUVmax values proved significantly related to GG and to be significantly higher in BSAs when compared to WSAs. Also, SUVmax significantly correlated with serum PSA values, which was significantly higher in BSAs when compared with WSAs.

We report a case of a 65-year-old man with prostate cancer; his treatment history included radical prostatectomy followed by radiation therapy and subsequent androgen deprivation therapy for more than 5 years. He currently presented with a history of rising prostate-specific antigen and complained of jaw aches. Ga-prostate-specific membrane antigen PET/CT study performed for suspected biochemical recurrence demonstrated vertebral lesions and lesion in his jaw. Subsequent biopsy of jaw lesion demonstrated prostate cancer metastases.

Ubiquicidin is an antimicrobial peptide with great potential for nuclear imaging of infectious diseases, as its cationic-rich fragment TGRAKRRMQYNRR (UBI) has been functionalized with NOTA to allow complexation to 68 Ga ( 68 Ga-NOTA-UBI). We herein assess the cytotoxicity and radiation dosimetry for 68 Ga-NOTA-UBI and a first-in-human evaluation to diagnose infectious processes. Methods: Cytotoxicity was evaluated in green monkey kidney epithelial (Vero) cells and MT-4 leukocytes. Tracer susceptibility was studied in vitro using different bacterial and fungal strains. PET/CT-based biodistribution, pharmacokinetics, and radiation dosimetry were performed on nonhuman primates. Two healthy volunteers and 3 patients with suspected infection underwent 68 Ga-NOTA-UBI PET/CT imaging. Results: Negligible cytotoxicity was determined for NOTA-UBI. 68 Ga-NOTA-UBI showed moderate blood clearance (29-min half-life) and predominant renal clearance in nonhuman primates. Human radiation dose estimates indicated the bladder wall as the dose-critical tissue (185 μSv/MBq), followed by the kidneys (23 μSv/MBq). The total absorbed body dose was low (<7 μSv/MBq); the effective dose was estimated at 17 μSv/MBq. 68 Ga-NOTA-UBI could diagnose bone- and soft-tissue infection in 3 of 3 patients. Conclusion: 68 Ga-NOTA-UBI is considered a nontoxic, safe-to-administer radiopharmaceutical unlikely to cause adverse effects in humans. The favorable tracer biodistribution and the first-in-human results will make 68 Ga-NOTA-UBI PET/CT an encouraging future diagnostic technique with auxiliary clinical relevance., (© 2018 by the Society of Nuclear Medicine and Molecular Imaging.)

The objective of this study was to assess the impact of 68 Ga-prostate-specific membrane antigen ( 68 Ga-PSMA) PET/CT on the management of prostate cancer in patients with biochemical recurrence (BCR). Methods: Documented management plans before and after 68 Ga-PSMA PET/CT in 100 patients with BCR were retrospectively reviewed, and changes in plans were recorded. Results: Management changed after 68 Ga-PSMA PET/CT in 39 patients (39%). The management changes occurred in 23 (33.8%) of 68 patients with radical prostatectomy and 16 (50%) of 32 patients previously treated with radical radiotherapy. Positive scan results ( P < 0.001) and higher prostate-specific antigen (PSA) levels ( P = 0.024) were associated with management changes. No significant association with management change was found for Gleason grade, stage, presence of metastatic disease, PSA velocity, or PSA doubling time. Conclusion: 68 Ga-PSMA PET/CT altered management in 39% of patients with BCR, and changes occurred more often in patients with radical radiotherapy treatment, positive 68 Ga-PSMA scan results, and higher PSA levels., (© 2018 by the Society of Nuclear Medicine and Molecular Imaging.)

We report the case of a 32 year-old male with Chondroblastic Osteosarcoma of the skull, which was imaged with both 18 [F]fluorodeoxyglucose ( 18 F-FDG) positron emission tomography/computed tomography (PET/CT) and 68 Gallium-arginine-glycine-aspartic acid ( 68 Ga-RGD) PET/CT. The 18 F-FDG PET/CT did not demonstrate the tumour, whereas the 68 Ga-RGD PET/CT clearly depicted a left-sided frontal tumour. 68 Ga-RGD PET/CT may be a clinically useful imaging modality for early detection of recurrent osteosarcoma, considering the limitations of 18 F-FDG PET in a setting of low glycolytic activity.

Aim: To evaluate the diagnostic accuracy of FDG PET/CT in the detection of asymptomatic recurrence in patients with malignant melanoma who have had resection of their primary lesion. We also aimed to determine the pattern and factors predisposing to disease recurrence., Methods: Patients with malignant melanoma who have had surgical resection of their disease and without any clinical evidence of disease recurrence were followed-up with FDG PET/CT. The diagnostic accuracy of FDG PET/CT, pattern of recurrence and factors predictive of disease recurrence were determined., Results: A total of 144 patients were followed-up for a median period of 50.50 months. Asymptomatic recurrence was seen in 37 patients (25.7 %) with a median time to recurrence of 20 months. Lymph node was the commonest site of asymptomatic recurrence. Sex, tumour depth, histology type and presence of nodal metastasis were significant predictors of tumour recurrence. Age, race, site of primary lesion, type of lymph node resection were not significant predictors of disease recurrence. Race has a significant effect on the histological subtype of tumour (nodular maligna was more common in Caucasian while acral lentiginous was more prevalent in the Blacks) and the site of the primary lesion (lower limb in Blacks and trunk in Caucasians). Sensitivity, specificity and accuracy of FDG PET/CT for the detection of disease recurrence were 94.5 %, 87.6 % and 89.6 % respectively., Conclusion: FDG PET/CT is a suitable modality for early detection of asymptomatic recurrence of malignant melanoma. Asymptomatic recurrence most commonly occurs in lymph nodes. Sex, nodal metastasis and tumour pathologic features are predictors of recurrence.

Objective: In this study we aimed to present our experience on the use of Gallium-68-dotatate with positron emission tomography, computed tomography ( 68 Ga-dotatate PET/CT) in the management of neuroendocrine tumors (NET) and other somatostatin expressing tumors., Subjects and Methods: We retrospectively reviewed patients with histologically confirmed or biochemically suspected NET and other somatostatin expressing (SSTR) tumors imaged at our department with 68 Ga-dotatate PET/CT. We determined the performance of this imaging technique as well as its impact on patients management. A total of 203 patients were studied: 103 females, 100 males median age 52years., Results: The commonest tumor type was gastroenteropancreatic NET (41% of patients) and the commonest sites of distant metastases were lymph nodes and the liver 34.0% and 30.5% respectively. Positron emission tomography detected foci of disease in 19 patients where CT was falsely negative. The sensitivity, specificity, positive predictive value, negative predictive value and accuracy of 68 Ga-dotatate PET/CT imaging of NET and other SST expressing tumors were 94.16%, 91.89%, 95.55%, 89.47% and 96.55% respectively., Conclusion: Gallium-68-dotatate PET/CT was better than CT in detecting primary sites of the disease and highly sensitive and specific for diagnosis and treatment of NET and other SSTR expressing tumors.

Background: To report on imaging findings using 68 Ga-PSMA-HBED-CC PET in a series of 19 breast carcinoma patients., Methods: 68 Ga-PSMA-HBED-CC PET imaging results obtained were compared to routinely performed staging examinations and analyzed as to lesion location and progesterone receptor status., Results: Out of 81 tumor lesions identified, 84% were identified on 68 Ga-PSMA-HBED-CC PET. 68 Ga-PSMA-HBED-CC SUVmean values of distant metastases proved significantly higher (mean, 6.86, SD, 5.68) when compared to those of primary or local recurrences (mean, 2.45, SD, 2.55, p = 0.04) or involved lymph nodes (mean, 3.18, SD, 1.79, p = 0.011). SUVmean values of progesterone receptor-positive lesions proved not significantly different from progesterone receptor-negative lesions. SUV values derived from FDG PET/CT, available in seven patients, and 68 Ga-PSMA-HBED-CC PET/CT imaging proved weakly correlated (r = 0.407, p = 0.015)., Conclusions: 68 Ga-PSMA-HBED-CC PET/CT imaging in breast carcinoma confirms the reported considerable variation of PSMA expression on human solid tumors using immunohistochemistry.

Introduction: Radioiodine ablation of remnant thyroid tissue is an important adjuvant therapy of differentiated thyroid carcinoma (DTC) after thyroidectomy. Elevated serum thyroid-stimulating hormone (TSH) level is necessary for successful ablation. The optimum level of serum TSH level necessary for successful radioiodine ablation of well-DTC is, however, yet to be defined. We aimed to determine whether higher serum TSH level will result in a better rate of complete ablation of well-DTC using iodine-131 (I) following initial thyroidectomy., Patients and Methods: A total of 109 patients with differentiated thyroid cancer were divided into four treatment groups on the basis of serum TSH levels. They were followed up from 6 to 12 months after treatment with stimulated serum thyroglobulin level and a diagnostic whole-body scan with radioactive iodine I to determine early response., Results: Sixty-four patients had papillary thyroid carcinoma, whereas 45 patients had follicular carcinoma. An excellent response was observed in 66.7% of patients with TSH level more than 90 μIU/ml, 72.2% in the group with TSH level of 60-89 μIU/ml, 48.5% when TSH was 30-59 μIU/ml and 26.7% when TSH was less than 30 μIU/ml (P=0.002)., Conclusion: Higher preablative serum TSH predicts a better rate of ablation in patients with differentiated thyroid cancer treated with I after thyroidectomy.