The prognostic role of whole-body volumetric 68 GA-DOTATATE PET/computed tomography parameters in patients with gastroenteropancreatic neuroendocrine tumor treated with 177 LU-DOTATATE.

OBJECTIVE: The aim of this study is to evaluate the prognostic role of Response Evaluation Criteria in Solid Tumors (RECIST) 1.1 and quantitative 68 Ga-DOTATATE PET/computed tomography parameters such as maximum standardized uptake value (SUVmax), mean SUV (SUVmean), DOTATATE tumor volume (DTV), total lesion DOTATATE (TLD) in patients with gastroenteropancreatic neuroendocrine tumors (GEP-NETs) treated with 177 Lu-DOTATATE. MATERIAL AND METHOD: Our retrospective study included 21 patients with GEP-NETs treated with 177 Lu-DOTATATE between January 2017 and January 2022. SUVmax, SUVmean, SUVmax/spleenSUVmax (SUVmax/Sx), DTV, TLD, SUVmean/spleenSUVmean (SUVmean/Sm), TLD/Sm values were calculated and recorded for all patients before and after 177 Lu-DOTATATE treatment. RESULTS: A total of 319 metastases were detected in the patients included in the study, and a total of 68 target lesions were selected. In univariant Cox regression analysis, TLD/Sm percent change (∆TLD/Sm) was found to be statistically significant on overall survival (OS) ( P  = 0.044). The 3-year survival in nonresponders was 50% ( P  = 0.034) based on ∆SUVmax/Sx values, 50% ( P  = 0.002) based on RECIST values, 50% based on ∆TDTV + new lesion values ( P  = 0.033), and according to ∆TTLD + new lesion values, it was 66% ( P  = 0.030). CONCLUSION: In our study, we showed that SUVmax/Sx, RECIST, ∆TDTV + new lesion, and ∆TTLD + new lesion parameters can predict OS in the evaluation of response to treatment.

The role of (68Ga)PSMA I&T in biochemical recurrence after radical prostatectomy: detection rate and the correlation between the level of PSA, Gleason score, and the SUVmax.

OBJECTIVE: The aim of the study was to retrospectively evaluate the recurrence detection rate of Gallium-68-prostate-specific membrane antigen [(68Ga)PSMA] imaging and therapy (I&T) positron emission tomography/computed tomography (PET/CT) at different PSA levels, which enables early detection of patients with radical prostatectomy. We also aimed to compare Gleason scores, used drugs (LHRH analogs and antiandrogens), PSA levels with SUVmax values, and detection rates. METHOD: This retrospective study included 107 patients who underwent radical prostatectomy and who underwent (68Ga)PSMA I&T PET/CT imaging between January 2015 and December 2018 for the early detection of recurrence. The PSA values, Gleason scores, treatments, lesions detected on (68Ga)PSMA I&T, and SUVmax values were recorded for all patients. RESULTS: Patients with a median PSA level of 1.22 ng/mL were divided into seven groups according to the PSA values. The lowest lesion detection rate was found to be 7/16 patients (43.8%) when the PSA was < 0.2 ng/ml, and the highest lesion detection rate was found to be 33/33 patients (100%) when the PSA was > 3.5 ng/ml. There was a positive correlation between PSA level and ppSUVmax (per patient SUVmax) value of the patients with lesions (p < 0.001 and r = 0.49). As the Gleason score increased, the lesion detection rates also increased and there was a significant correlation between these values (p < 0.001 and r = 0.360). A positive correlation was determined between the Gleason scores and ppSUVmax values in patients with lesions (p = 0.007 and r = 0.302). A statistically significant correlation was found between bicalutamide use and lesion detection on (68Ga)PSMA I&T (p < 0.001). A similar relationship was also determined in patients undergoing maximal androgen blockade (MAB) (p = 0.003). Patients determined with lesions on (68Ga)PSMA I&T and who were administered luteinizing hormone-releasing hormone (LHRH) agonists were found to have statistically significantly higher ppSUVmax values than those who were not administered LHRH agonists (p < 0.001). In binary logistic regression test, when PSA levels and Gleason scores were selected as continuous variables, both PSA levels and Gleason scores were demonstrated as significant covariates (p = 0.006 and p = 0.022) for lesion detection; by contrast, bicalutamide and MAB were not found as significant factors. CONCLUSION: In the present study, (68Ga)PSMA I&T was found to be quite successful in determining lesions in the biochemical recurrence, which is consistent with the findings of other I&T studies and studies conducted with different PSMA ligands. Thus, it can be considered that the use of (68Ga)PSMA I&T will become increasingly common.

Contrast Enhanced [99mTc] MIBI SPECT/CT in Primary Hyperparathyroidism.

OBJECTIVE: The aim of the present study was to compare the surgical results with contrast-enhanced [99mTc]methoxyisobutylisonitrile ([99mTc]MIBI) single-photon emission computed tomography (SPECT)/computed tomography (CT) results by adding the simultaneous single phase contrast to the [99mTc]MIBI SPECT/CT examination. METHOD: Between November 2016 and January 2018, 24 (21 female, 3 male) patients who underwent an operation after preoperative contrast-enhanced [99mTc]MIBI SPECT/CT, and 49 asymptomatic patients (42 female, 7 male), who did not undergo surgery, were included in the study. RESULTS: Sensitivity and specificity rates of contrast enhanced [99mTc]MIBI SPECT/CT were 100% and 100% when evaluated together with surgical results. The rate of detection in asymptomatic patients was found to be 93.8%. CONCLUSIONS: With the contrast-enhanced [99mTc]MIBI SPECT/CT imaging, both high sensitivity and specificity values were achieved in the preoperative localization of parathyroid adenomas (PTAs) and high detection rates were obtained in the asymptomatic group. The use of contrast IV during the [99mTc]MIBI SPECT/CT in patients without contraindications increased both preoperative localization rates of adenomas and detection rates of asymptomatic hyperparathyroidism cases. KEY WORDS: Parathyroid adenoma, Primary Hyperparathyroidism, [99mTc]MIBI, SPECT/CT.

Prognostic value of 68 Ga PSMA I&T PET/CT SUV parameters on survival outcome in advanced prostat cancer.

OBJECTIVE: To determine the association of 68 Ga-PSMA-I&T PET/CT SUV parameters with survival outcome in advanced prostate cancer patients. METHODS: A total of 148 consecutive patients mean age: 69.3 ± 7.8 years with advanced prostate cancer who underwent 68 Ga-PSMA-I&T PET/CT were included in this retrospective study. Data on previous treatments, serum PSA levels (ng/mL), 68 Ga-PSMA-I&T PET/CT findings metastases as well as survival data were recorded. RESULTS: Multivariate regression analysis revealed that Level 1 LN SUV/Liver SUV ratios > 2.17 (OR 4.262; 95% CI 1.104-16.453, p = 0.035), bone SUV > 10.7(OR 23.650; 95% CI 4.056-137.888, p < 0.001), bone SUV/spleen SUV ratio > 1.842 (OR 25.324; 95% CI 4.204-152.552, p < 0.001), highest SUVmax/liver SUV ratio > 2.32 (OR 19.309; 95% CI 1.730-209.552, p = 0.016) and highest SUVmax/spleen SUV ratio > 1.842 (OR 22.354; 95% CI 2.637-189.493, p = 0.004) were significant in the determination of increased mortality risk in advanced prostate cancer patients. CONCLUSION: Our findings, for the first time in literature, provided evidence on potential utility of tracer uptake (SUV) cut-off values on 68 Ga-PSMA PET/CT in identification of the survival outcome of patients with metastatic disease and thereby in assisting in the selection of individualized therapeutic strategies tailored to the expected prognosis.

The prognostic value of preoperative PET/CT evaluation of maximum standardized uptake value in renal cell carcinomas.

AIM: The use of positron emission tomography (PET/CT) in kidney tumors has increased greatly in recent years. There have been few studies on the effect of SUVmax values detected by PET/CT on the mortality and survival estimation in patients with kidney tumors. In this study, it is hoped to contribute to the literature of research on survival and mortality estimations of kidney tumour patients through an evaluation of SUVmax values measured with PET/CT scan. MATERIAL AND METHODS: A retrospective review was made of the files of 21 patients newly-diagnosed with kidney tumor and with disease staging determined with PET/CT in the Nuclear medicine Department of Saglik Bilimleri University Diyarbakir Gazi Yasargil Training and Research Hospital between August 2007 and April 2012. The largest tumor seen on CT was considered as the tumour size and was stated in cm. The survival time was defined as the time from the date of PET/CT Imaging, which was taken into consideration while calculating the survival, and the date of death received from MERNIS (The Central Civil Registration System) or the final application date if the patient was alive. RESULTS: The lower the SUVmax value in the kidney tumour, the longer the survival time. The mortality risk of male patients was 12-fold higher than females and mortality increased 4-fold when SUVmax values were ≥ 4.5.Patients with a tumour on the right kidney had a longer survival time. With increasedage,survival time decreased. The SUVmax values and tumor size measured in left kidney tumors were higher than those measured in right kidney tumors. CONCLUSIONS: In the present study, it was concluded that the lower the SUVmax values and the smaller the tumour size, the longer the survival time. Mortality rates increased when SUVmax values were ≥ 4.5 (p=0.001).The use of PET/CT scan can be considered to contribute to mortality and survival estimations in patients with kidney tumor. KEY WORD: FDG, Renal cell Carcinoma, SUVmax.

Evaluation of Nasal Mucociliary Transport Rate byTc-Macroaggregated Albumin Rhinoscintigraphy in Woodworkers.

Woodworkers in the furniture industry are exposed to wood dust in their workplaces. The aim of this study is to investigate the effect of occupational wood dust exposure on the nasal mucociliary transport rates (NMTRs) in woodworkers. Twenty five woodworkers and 30 healthy controls were included in this study. Wood dust concentration in workplaces was measured using the sampling device. (99m) Tc-macroaggregated albumin ((99m)Tc-MAA) rhinoscintigraphy was performed, and NMTR was calculated in all cases. In statistical analysis, an independent samples t-test was used to compare NMTR of woodworkers and control subjects. We found that the mean NMTR of the woodworkers was lower than that of the healthy controls. However, there was not a statistically significant difference between them (P = 0.066). In conclusion, our findings suggested that wood dust exposure may not impair nasal mucociliary transport rate in woodworkers employed in joinery workshops.