The role of PSMA PET/CT in predicting downgrading in patients with Gleason score 4+4 prostate cancer in prostate biopsy.

BACKGROUND: To investigate the predictable parameters associated with downgrading in patients with a Gleason score (GS) 8 (4+4) in prostate biopsy after radical prostatectomy. METHODS: We retrospectively analyzed 62 patients with a GS of 4+4 on prostate biopsy who underwent robotic radical prostatectomy between 2017 and 2022. RESULTS: 38 of 62 (61.2%) were downgraded. In multivariable logistic regression model, Ga-68 prostate-specific membrane antigen (PSMA) positron-emission tomography (PET)/computed tomography (CT) SUV max was independent predictor of downgrading (OR 0.904; p = 0.011) and a Logistic Regression model was constructed using the following formula: Y = 1.465-0.95 (PSMA PET/CT SUV max). The model using this variable correctly predicted the downgrading in 72.6% of patients. The AUC for PSMA PET/CT SUV max was 0.709 the cut off being 8.8. A subgroup analysis was performed in 37 patients who had no other European Association of Urology (EAU) high risk features. 25 out of 37 (67.5%) were downgraded, and 21 of these 25 had organ confined disease. Low PSMA SUV max (<8.1) and percentage of GS 4+4 biopsy cores to cancer bearing cores (45.0%) were independently associated with downgrading to GS 7. CONCLUSION: PSMA PET/CT can be used to predict downgrading in patients with GS 4+4 PCa. Patients with GS 4+4 disease, but no other EAU high risk features, low percentage of GS 4+4 biopsy cores to cancer bearing cores, and a low PSMA PET/CT SUV max are associated with a high likelihood of the cancer reclassification to intermediate risk group.

Radioligand Therapy With 177 Lu-PSMA-I&T in Patients With Metastatic Prostate Cancer : Oncological Outcomes and Toxicity Profile.

INTRODUCTION: This study aimed to investigate the oncological outcomes and toxicity profile of 177 Lu-PSMA-I&T radioligand therapy (RLT) in patients with metastatic castration-resistant prostate cancer (mCRPC), as well as our initial experience in metastatic hormone-sensitive prostate cancer (mHSPC). PATIENTS AND METHODS: A total of 38 consecutive patients with metastatic prostate cancer (33 mCRPC and 5 mHSPC) received 177 Lu-PSMA-I&T RLT, with a median of 2 cycles per patient (range, 1-7). Response to RLT was evaluated based on prostate-specific antigen (PSA) changes and imaging response. Clinical progression-free survival and overall survival were used to report oncological outcomes. Toxicity was assessed using the Common Toxicity Criteria for Adverse Events criteria. RESULTS: In mCRPC, 22 (69%), 18 (56%), and 11 (34%) patients achieved any PSA decline, PSA response of ≥30%, and PSA response of ≥50%, respectively. The clinical progression-free survival and overall survival after the first cycle of RLT were 6.3 and 21.4 months, respectively. In mHSPC, 177 Lu-PSMA-I&T RLT resulted in excellent PSA response (93.0%-99.9%) in all cases. Clinical progression and cancer-related mortality occurred in only 1 case. Toxicity profile was favorable in both mHSPC and mCRPC. CONCLUSIONS: 177 Lu-PSMA-I&T RLT demonstrated favorable PSA response (≥30%) in over half of the patients with mCRPC and excellent PSA response in all patients with mHSPC. Toxicity profile was favorable in both mHSPC and mCRPC settings. Further studies are needed to evaluate the role of 177 Lu-PSMA-I&T RLT in the management of metastatic prostate cancer.

Previous, simultaneous, or subsequent occurrence of malignant tumours in patients with primary hyperparathyroidism: a closer look at the single-tertiary-centre cases.

INTRODUCTION: Our aims were to explore the relationship between primary hyperparathyroidism (pHPT) and malignant tumour development, to determine the frequency and the time of occurrence of malignant tumours in patients with pHPT, and to evaluate the characteristics of pHPT in these patients. MATERIAL AND METHODS: This retrospective cohort study included consecutive individuals who were diagnosed with pHPT aged 18 years or older in a university hospital during a 7-year period. A total of 198 patients with pHPT were reviewed retrospectively. Demographic, clinical, biochemical, radiologic findings, and histopathological diagnosis were collected from the electronic medical records of the hospital system. RESULTS: The mean age of the study population was 58 ± 13 years and was predominantly female (female/male: 162/36). There were 42 (21.2%) patients with malignant tumours. Five (12%) out of 42 patients had metachronous double malignancies. The most common 2 concurrent malignancies were breast (36.1%) and thyroid (17.0%). Sixty-eight per cent of the malignant tumours occurred before the diagnosis of pHPT. A higher percentage (87.5%) of simultaneous tumours was seen in the thyroid gland. No statistically significant differences were observed between patients with and without malignant tumours in terms of demographic, clinical, biochemical, radiological, and histopathological features. The median follow-up duration was 24 months after parathyroid surgery. CONCLUSION: The results of this study revealed that pHPT was associated with various tumour types. The frequency of malignant tumours was 21.2%. Breast and thyroid cancers were the most common 2 cancers coexisting with pHPT. A large percentage of malignant tumours occurred before the diagnosis of pHPT. A higher percentage of simultaneous tumours was seen in the thyroid gland. pHPT patients with and without malignant tumours seemed to have similar characteristics.

Intraoperative Frozen Section via Neurosafe During Robotic Radical Prostatectomy in the Era of Preoperative Risk Stratifications and Primary Staging With mpMRI and PSMA-PET CT: Is There a Perfect Candidate?

BACKGROUND: We aimed to analyze the effect of preoperative risk assessment including Ga-68 PSMA PET and multiparametric magnetic resonance imaging (mpMRI) on nerve sparing practices, positive surgical margin (PSM) rates and oncological outcomes based on a comparison between patients underwent RARP with and without Neurosafe (NS). METHODS: Patients underwent RARP with NS (RARP-NS) or without (RARP-only) NS retrospectively evaluated. Suspicion for extracapsular extension on mpMRI and/or Ga-68 PSMA PET was recorded as i(imaging)T3. NS was performed according to the Martini-Klinik technique. PSM at preserved bundle side were called PSM at region of interest (ROI) while the others were elsewhere. RESULTS: A total of 208 patients (90 in RARP-NS, 118 in RARP-only groups) were included. Preoperatively the RARP-only group showed significantly higher mean PSA (p = .01) and PIRADS 5 (p = .002) findings and had more D'Amico high risk (DAHR) patients (p = .08). The overall PSM rates for pT2 versus pT3 disease were 7.5% versus 21.6 and 15.6% versus 55% in RARP-NS and RARP-only groups, respectively. NS resulted in more bilaterally preserved bundles (81.1% vs. 66.3%) and less PSM at the ROI (3.3% vs. 23.4%) than RARP-only group. NS outperformed RARP-only in all clinical settings had its highest differential benefit in more bilateral nerve sparing and less PSM at ROI in patients with both DAHR and iT3 disease. BCR rates were 2.2% and 2.5% for RARP-NS and RARP only groups, respectively (p = .4). One patient in RARP-NS and 9 in RARP-only groups had PSA persistence (p = .02). CONCLUSION: RARP-NS led to more preserved bundles with less PSM. It was especially useful in DAHR patients with preoperative extracapsular extension suspicion in imaging simultaneously.

Early Post-operative Stimulated Serum Thyroglobulin: Role in Preventing Unnecessary Radioactive Iodine Treatment in Low to Intermediate Risk Papillary Thyroid Cancer.

AIM: The aims of the study are to evaluate the predictive value of early post-operative stimulated thyroglobulin (sTg) analysis on the recurrence risk, and to define a cut-off value that is related to recurrence risk in low to intermediate risk papillary thyroid cancer (PTC). METHODS: This retrospective cohort study included individuals who were diagnosed with PTC aged 18 years or older and had been operated by experienced surgeons of a tertiary university hospital between the years 2011 and 2021. The American Thyroid Association thyroid cancer guidelines version 2015 was used as the risk stratification system. Early sTg measurement obtained at 3-4 weeks after surgery when TSH >30 µIU/mL. Data was collected from the hospital database. A total of 328 patients who had post-operative early sTg values with negative anti-Tg antibodies were included. RESULTS: The median age was 44 years. Of the 328 patients, 223 (68%) were women. The median tumor diameter was 11 mm. One hundred ninety-one patients (58.2%) had low risk and 137 (41.8%) had intermediate risk for recurrent disease. Of the 328 patients, 4.0% had recurrent disease. In multivariate Cox regression, post-operative early sTg value [OR: 1.070 (1.038-1.116), P = .000], and the pre-operative malign cytology [OR: 1.483 (1.080-2.245), P = .042] were independent risk factors for recurrence. On the ROC curve analysis, the cut-off value of early sTg was 4.1 ng/mL for those with recurrent disease. CONCLUSION: This study demonstrated that early sTg could predict recurrent disease in patients with low to intermediate risk PTC. A cut-off of 4.1 ng/mL was identified with a high negative predictive value.

Diagnostic Performance of 68Ga-PSMA-11 Positron Emission Tomography/Computed Tomography to Monitor Treatment Response in Patients with Metastatic Prostate Cancer: The Concordance Between Biochemical Response and Prostate-specific Membrane Antigen Results.

BACKGROUND: Treatment response is traditionally monitored using prostate-specific antigen (PSA) and conventional imaging in patients with metastatic prostate cancer (mPCa). OBJECTIVE: To assess the diagnostic performance of prostate-specific membrane antigen (PSMA) positron emission tomography (PET)/computed tomography (CT) when monitoring mPCa patients receiving systemic treatment and also to investigate the concordance between PSMA PET response according to the PSMA PET progression (PPP) criteria and biochemical response. DESIGN, SETTING, AND PARTICIPANTS: A total of 96 patients with 68Ga-PSMA-11 PET/CT-detected mPCa at baseline PSMA PET/CT (bPSMA) who underwent at least one follow-up scan after receiving systemic treatment were included in the study. PSA levels at bPSMA and follow-up PSMA PET (fPSMA) scans were recorded. The PPP criteria were used to define PSMA progression. Biochemical progression was defined as ≥25% increase in PSA. PSMA PET and PSA responses were dichotomized into progressive disease (PD) versus non-PD, and the concordance between PSA and PSMA responses was evaluated. OUTCOME MEASUREMENTS AND STATISTICAL ANALYSIS: The concordance between PSA and PSMA PET responses was presented using frequencies, percentages, and Cohen's kappa test. RESULTS AND LIMITATIONS: A total of 345 serial PSMA PET/CT (96 bPSMA and 249 fPSMA) scans were evaluated. The positivity rates of PSMA PET scans for PSA levels of <0.01, 0.01-0.2, 0.2-4, and >4 ng/ml were 55.6%, 75.0%, 100%, and 98.8%, respectively. PSA and PSMA responses showed moderate-to-high concordance (Cohen's κ = 0.623, p < 0.001). PSA-PSMA discordance was detected in 39 scans (17%). The most common cause of discordance was the discordant results between different metastatic lesions (16/28, 57.1%) in patients with PPP without PSA progression and local progression in prostate (n = 7/11, 63.6%) in patients with PSA progression without PPP. CONCLUSIONS: PSMA PET/CT showed very high detection rates of malignant lesions even at very low PSA values and showed significant concordance with PSA response when monitoring treatment response in patients receiving systemic treatment for mPCa. PATIENT SUMMARY: This study describes that prostate-specific membrane antigen positron emission tomography (PSMA PET), a new sensitive imaging tool, can detect malignant lesions even at very low prostate-specific antigen values when monitoring metastatic prostate cancer. The PSMA PET response and biochemical response showed significant concordance, and the reason for discordant results seems to be the different responses of metastatic lesions and prostatic lesions to systemic treatment.

18F-FDG PET/CT texture analysis of anthracotic lymph nodes detected with EBUS and comparison with cytological findings.

OBJECTIVE: Lymph node metastasis is the most important factor both in the selection of treatment since many alternatives have been created in recent years, and in the evaluation of prognosis in lung cancer. The most unpredictable cause of lymph node false positivity in fluorine-18-fluorodeoxyglucose (18F-FDG) positron emission tomography/computed tomography (PET/CT) is anthracosis. The aim of this study is to compare 18F-FDG PET/CT texture information of anthracotic (ALN) and metastatic (MLN) lymph nodes, after re-evaluation of the cytological samples obtained from anthracotic lymph nodes by EBUS-TBNA. SUBJECTS AND METHODS: Ninety nine patients, 78 of whom had primary lung cancer were included in the study. Two hundred and three lymph nodes from 99 patients sampled by EBUS-TBNA and diagnosed cytologically as ALN or MLN were evaluated retrospectively. All ALN were classified as grades 1, 2 and 3 cytologically. Volume of interest (VOI) of 203 lymph nodes was re-drawn and maximum standardized uptake value (SUVmax), metabolic tumor volume (MTV) and total lesion glycolysis (TLG) values were recorded. RESULTS: There was a statistically significant difference in MTV and TLG values in MLN and all ALN grades. However, only grade 1-2 ALNs could be differentiated from MLNs with SUVmax, and no statistically significant difference was found in grade 3 ALN and MLN. Metabolic tumor volume and TLG values over 4.10cm3 and 26.57 showed 60% and 59% sensitivity and 83% and 94 specificity respectively for the identification of MLN. CONCLUSION: The contribution of MTV and TLG values of 18F-FDG PET/CT to the differential diagnosis of ALN is much more valuable than SUVmax values, especially for grade 3 anthracosis. It was thought that cytological reporting of only grade 3 ALN could make a better contribution to the 18F-FDG PET/CT evaluation analysis.

Extramedullary Relapsed Multiple Myeloma Treatment With 177Lu-Labeled CXCR4 Endoradiotherapy and Dosimetric Results.

ABSTRACT: We created our first national clinical protocol of 177Lu-CXCR4 therapy for patient who have failed to respond to current therapy options. We also calculated the kidney, liver, and tumor dosimetry. The kidney's mean absorbed dose was calculated to be 0.45 Gy/GBq, the calculated radiation absorbed dose of the liver was 0.63 Gy/GBq, and the radiation absorbed doses of the tumors vary between 9.2 and 82 Gy/GBq. 177Lu-CXCR4 therapy produced a promising clinical response in our patient in acceptable radiation dose limits as a treatment option in heavily pretreated patients with advanced multiple myeloma.

68Ga-PSMA-11 Positron Emission Tomography/Computed Tomography for Primary Lymph Node Staging Before Radical Prostatectomy: Central Review of Imaging and Comparison with Histopathology of Extended Lymphadenectomy.

BACKGROUND: Results from prospective trials have shown higher accuracy of prostate-specific membrane antigen (PSMA)-based positron emission tomography (PET)/computed tomography (CT) in detection of lymph node metastasis (LNM) compared to conventional imaging. OBJECTIVE: To evaluate the accuracy of 68Ga-PSMA-11 PET/CT for LNM detection in patients undergoing radical prostatectomy (RP) and extended pelvic lymph node dissection (PLND). DESIGN, SETTING, AND PARTICIPANTS: Between June 2014 and November 2020, 96 patients with 68Ga-PSMA PET/CT for primary staging underwent RP and extended PLND. OUTCOME MEASUREMENTS AND STATISTICAL ANALYSIS: The results from 68Ga-PSMA PET/CT were compared with histologic data from primary PLND in 96 patients. All 68Ga-PSMA PET/CT scans were centrally reviewed. RESULTS AND LIMITATIONS: Of 96 patients, 15.6% (n = 15) harbored LNMs. The median prostate-specific antigen at 68Ga-PSMA PET/CT was 8.0 ng/ml (interquartile range 5.5-11.7). The majority of patients had intermediate- (52.1%) or high-risk disease (41.7%). Biopsy grade group 4 and 5 was present in 22.9% and 15.6%, respectively. The 68Ga-PSMA PET/CT scans identified eight of 15 patients (53.3%) as LN-positive (true positive). The calculated per-patient sensitivity, specificity, positive predictive value, negative predictive value, and accuracy of 68Ga-PSMA PET/CT in the detection of LNM were 53.3%, 98.8%, 88.9%, 92.0%, and 91.7%, respectively. The per-patient sensitivity and specificity in the detection of LNMs larger than 2 mm were 61.5% and 98.8%, respectively. The main limitation is the retrospective design of the study. CONCLUSIONS: 68Ga-PSMA PET/CT is accurate in lymph node staging and the results support its use for primary staging of prostate cancer. PATIENT SUMMARY: We compared prostate-specific membrane antigen (PSMA)-based positron emission tomography (PET)/computed tomography (CT) findings with histopathology results after extended lymph node dissection and showed that it is accurate in detecting lymph node metastases. Our results support the use of PSMA PET/CT for primary staging of prostate cancer.

Diagnostic ability of Ga-68 PSMA PET to detect dominant and non-dominant tumors, upgrading and adverse pathology in patients with PIRADS 4-5 index lesions undergoing radical prostatectomy.

BACKGROUND: To evaluate the additive role of Ga-68 PSMA PET as a primary staging tool in patients bearing prostate cancer in single PIRADS 4 or 5 index lesions. METHODS: Eighty-one biopsy-naive patients with preoperative mpMRI and Ga-68 PSMA PET who underwent radical prostatectomy (RP) were evaluated retrospectively. Forty-nine patients had PIRADS 4 and 32 had PIRADS 5 index lesions. The localization, grade, and volumetric properties of dominant (DT) and non-dominant tumors (NDT) in RP were compared to the index lesions of mpMRI and Ga-68 PSMA PET. RESULTS: The median age and PSA level were 62 (IQR; 59-69) years and 7 (IQR; 2-8) ng/ml, respectively. Ga-68 PSMA PET detected DTs in 100% of the patients including 13 patients in whom mpMR failed. In 45 patients an NDT was reported in RP. Ga-68 PSMA PET accurately detected NDT in 24 of 45 (53.3%) patients. Six patients (12.2%) in PIRADS 4 and 8 (25%) in PIRADS 5 group showed upgrading. In PIRADS 4, Ga-68 PSMA PET localized DT in all patients with upgraded tumors whereas mpMRI missed exact location in 2 of 6 (33.3%). In PIRADS 5 both mpMRI and Ga-68 PSMA PET accurately located all DTs. Overall detection rates of extracapsular extension (ECE) and seminal vesicle invasion (SVI) by mpMRI were 51.1% and 53.8%, respectively. Ga-68 PSMA PET detected ECE and SVI in 27.9% and 30.7%, respectively. When mpMRI and Ga-68 PSMA PET were used in combination detection rates of ECE and SVI increased to 65.1 and 61.5%. Ga-68 PSMA PET-detected six of ten patients with positive lymph nodes whereas mpMRI could not identify any. CONCLUSIONS: Ga-68 PSMA PET has a better diagnostic accuracy in detecting DT, NDT, upgrading, adverse pathology in patients with PIRADS 4 index lesions. However, mpMRI better predicted ECE and SVI than Ga-68 PSMA PET.

The use of focused, radioguided parathyroidectomy in geriatric patients with a history of thyroid surgery.

OBJECTIVE: Geriatric patients are often reluctant to undergo parathyroid surgery under general anesthesia because of the major comorbidities. The use of minimally invasive techniques for parathyroid lesions under local anesthesia have been published. Radioguided lesion localization has been known to decrease operative time and reduce the occurrence of positive margins in breast cancer surgery. We hypothesize that it could also be effectively used in focused parathyroid surgery in geriatric patients with in history of thyroid surgery. MATERIALS AND METHODS: Our study group consists of geriatric patients with a history of thyroid surgery who underwent focused parathyroid surgery between February 2017 and October 2019. Group-1 included 18 patients who had parathyroidectomy under radioguidance. Group-2, 22 patients who had surgery without it. Patient demographics, operative time, number of frozen sections and length of hospital stay were analyzed. RESULTS: Analyzed data were similar between groups. The mean age of the patients was 72.56±12.65 years (range: 65-88). The operative times for group-1 and group-2, were 65.42±7.78 and 74.63±15.98 minutes, respectively (P=0.002). All patients were discharged uneventfully on postoperative day-2. CONCLUSION: Radioguidance parathyroidectomy positively affected the operative time and also decreased the need for additional frozen section.

Determination of thyroglobulin levels by radioimmunoassay method in anti thyroglobulin positive differentiated thyroid patients: One center clinical experience.

It is very crucial to determine Tg accurately and precisely in thyroid cancer cases. Although there are many studies on the detection of Tg in thyroid cases in the literature, there are no sufficient clinical studies examining many cases with different features by using RIA methodology. Here, a radiometric and chromatographic method has been studied for the first time to eliminate the interference from anti-Tg positive patients. In this paper, radioimmunoassay (RIA) and immunoradiometric (IRMA) techniques were used for the analysis of 302 sera collected from patients for Tg and TgAb quantification. By the RIA technique, a reliable result was obtained by calculating the real Tg value quantitatively in 41 patients showing TgAb positivity out of 208 patients. Our findings show that the RIA assay is the most suitable approach for detection of changeable (low or undetectable) Tg value and metastases detected by post-therapeutic imaging in early-stage DTC cases showing preoperative and postoperative TgAb positivity. The new immunoradiometric method allows the real (%) Tg value to be reached in a part of TgAb-positive DTC. Even if TgAb positive in the metastatic and nonmetastatic DTC patient group. This allows the accurate clinical follow-up of patients.

Tumor border pattern and size help predict lymph node status in papillary microcarcinoma: A clinicopathologic study.

OBJECTIVE: Lymph node metastasis occurs in a subset of papillary microcarcinoma patients. We aimed to analyze the differences between metastatic and non-metastatic papillary microcarcinomas in order to identify a high-risk subgroup that is likely to require more aggressive treatment. MATERIALS AND METHODS: 126 thyroidectomies with lymph node dissections (central ±â€¯lateral), diagnosed as papillary microcarcinoma, were reviewed. RESULTS: Mean age of 126 patients (F/M = 3.3) was 42 years. Mean size of the largest tumor was 7 mm. Classical was the most frequently (89%) encountered subtype. Multiple histologic subtypes co-occurred in 19%. Lymphovascular invasion was present in 16% (n = 20). 55 (44%) and 71 (56%) cases were unifocal and multifocal, respectively. 90 cases (71%) were non-encapsulated with overall infiltrative tumor borders, whereas in 36 cases (29%), the tumor had a well-defined capsule. Among those, 23 (64%) had tumor capsule invasion. 47 (37%) cases had metastasis in lymph nodes. In univariate analysis, metastasis was associated with tumor size of >5 mm (p = 0.02), tumor burden of >5 mm (p = 0.03), lymphovascular invasion (p = 0.02) and non-encapsulation (p = 0.01). No associations were found regarding sex, age, histologic subtype, lymphocytic thyroiditis, tumor capsule invasion (in capsulated tumors), laterality and multifocality (p > 0.05). In multivariate analysis, lymphovascular invasion (p = 0.01, OR = 3.97, 95% CI 1.35-11.67), tumor size >0.5 cm (p = 0.031, OR = 2.92, 95% CI 1.10-7.71) and non-encapsulation (p = 0.033, OR = 2.85, 95% CI 1.08-7.51) were independent risk factors. CONCLUSION: Size (largest tumor or sum of all foci) of >5 mm, non-encapsulation and lymphovascular invasion were independent predictors of LNM in PMs. Unifocal tumors metastasize the same as multifocal tumors, suggestive of the contribution of other factors. Patients with sporadically resected microcarcinomas should be carefully followed-up, especially those that harbor risk factors in histology.

Effect of prophylactic central neck dissection on the surgical outcomes in papillary thyroid cancer: experience in a single center.

PURPOSE: Morbidity due to papillary thyroid carcinoma (PTC) is increased mostly due to lymph node (LN) metastases, which lead to reoperations and complications associated with these operations. The aim is to compare the outcomes of PTC having total thyroidectomy and prophylactic central lymph node dissection (TT + PCND) with patients having total thyroidectomy (TT) alone. METHODS: This study is a retrospective cohort analysis of 358 PTC patients that were operated by a single surgeon in a single center. Data about the patients were extracted from the medical records. RESULTS: Of the patient cohort, 258 patients had TT + PCND (42.5 ± 11.3 years) and 100 patients (41.2 ± 11.9 years) had only TT. Total number of LN extracted in the TT + PCND group was 8.1 ± 6.9. The mean number of metastatic LN were 2.2 ± 1.9. Percentage of patients that had RAI were less in the TT + PCND group compared to the TT group. Seven patients (2.7%) in the TT + PCND group and 19 (19.0%) in TT group had recurrent disease (p < 0.0001). Of the complications, only transient hypoparathyroidism was increased in TT + PCND group compared to TT group (26.7% vs 10%, p < 0.0001). CONCLUSION: TT + PCND performed by an experienced surgeon seems to decrease the number of LN recurrences, and the need for reoperations.

Posttherapeutic Critical Organ Dosimetry of Extensive 177Lu-PSMA Inhibitor Therapy With Metastatic Castration-Resistant Prostate Cancer: One Center Results.

PURPOSE: Lu-PSMA inhibitor peptide receptor radioligand therapy (RLT) is playing an increasing role in metastatic castration-resistant prostate cancer. We aimed to estimate the absorbed radiation doses for critical organs (eg, kidneys, parotid glands, submandibular glands, and lacrimal glands) of patients treated with 4 to 6 cycles by Lu-PSMA inhibitor RLT, retrospectively, and to evaluate the findings extensively in order to determine the critical organ radiation-absorbed limitations and the number of prospective RLT. MATERIALS AND METHODS: A total of 51 cycles Lu-PSMA inhibitor RLT in 10 patients was analyzed. Therapies have been applied in 4 to 6 cycles with 8 to 10 weeks' intervals. Dosimetric estimates of kidneys, parotid glands, submandibular glands, and lacrimal glands have been calculated based on MIRD scheme pamphlet no. 16. Regions of interest were drawn with GE Xeleris Functional Imaging Workstation. OLINDA/EXM 1.1 simulation software was used to calculate radiation-absorbed doses. RESULTS: Mean radiation-absorbed doses were 0.70 ± 0.24 Gy/GBq for kidneys, 1.34 ± 0.78 Gy/GBq for parotid glands, 0.94 ± 0.45 Gy/GBq for submandibular glands, and 2.28 ± 1.29 Gy/GBq for lacrimal glands. CONCLUSIONS: Due to the critical target organ risks and the optimal therapy doses, patient-specific dosimetry is a deterministic factor in radionuclide therapy. Even when the absorbed kidney doses were above the ICRP critical dose limits in patients who had 4 to 6 cycles of therapy, mortality due to nephrotoxicity has not been observed. Mild increased tolerated radiation dose is acceptable for the patient groups with very low survival rate.

The clinicopathologic characteristics of familial and sporadic papillary thyroid carcinoma in Turkish patients

Background/aim: The aim of this study is to investigate clinicopathologic features of familial papillary thyroid carcinoma (fPTC) and compare them with sporadic papillary thyroid carcinoma (sPTC) in Turkish patients. A retrospective analysis of the papillary thyroid carcinoma (PTC) cases, with or without family history with a follow-up around 10 years was performed. Materials and methods: A series of patients with fPTC (82 fPTC families with 146 affected individuals) were compared with patients with sPTC (n = 112). The clinicopathologic features [(age, gender, histologic subtype, tumour size, bilaterality, multifocality, extrathyroidal extension (ETE), lymph node metastasis (LNM)] and treatment procedures (lymph node dissection, radioactive iodine ablation), and the outcomes like recurrences in the neck region, distant metastasis, and the need for reoperation were compared between the groups. Results: When the groups were compared, there was no significant difference in age (P = 0.449), and tumour size (P = 0.898) between familial and sporadic PTC patients. fPTC group had a significantly higher risk of male gender (P=0.001), bilaterality (P = 0.004), multifocality (P = 0.011), LNM (P = 0.013), ETE (P = 0.040), and distant metastasis (P ≤ 0.0001) than the sPTC group. However, recurrence rate was similar between the 2 groups (P = 0.436). Conclusion: The results of this study confirms a more aggressive nature in fPTC patients, in terms of bilaterality, multifocality, ETE, LNM, and distant metastasis, compared to sPTC patients in Turkish population.

Can Ga-68 PSMA PET/CT replace conventional imaging modalities for primary lymph node and bone staging of prostate cancer?

Imaging is critical for primary staging of prostate cancer. Traditional imaging modalities (computerized tomography scan and nuclear medicine bone scans) are limited by their suboptimal diagnostic performance. Recent meta-analyses have demonstrated that nuclear imaging with 68Ga-labeled prostate-specific membrane antigen ligand (68Ga-PSMA) using positron emission tomography/computed tomography (PET/CT) has higher sensitivity and specificity in this setting compared to conventional imaging techniques. 68Ga-PSMA PET/CT for whole-body assessment can be used as the sole imaging modality for primary lymph node and bone staging of prostate cancer. PATIENT SUMMARY: There is a rapidly growing body of evidence that nuclear imaging with 68Ga-labeled prostate-specific membrane antigen ligand using positron emission tomography/computed tomography has a higher detection rate for lymph node and bone metastases in prostate cancer patients. This approach has strong potential to replace conventional techniques in the primary setting in the near future.

False-Positive Pancreatic Uptake Detected on 68Ga-PSMA PET/CT: A Priority Changing Incidental Finding While Assessing the Need for a Prostate Biopsy.

A 72-year-old man underwent Ga-PSMA PET/CT because of an elevated prostate-specific antigen level despite prior prostatectomy. Besides low-intensity prostatic PSMA reactivities, a faintly PSMA-positive lesion in the pancreatic corpus drew attention, which seemed suggestive of a primary pancreatic cancer on the subsequent MRI and therefore had to be excised. The final diagnosis was pT3 low-grade neuroendocrine tumor. PSMA-positive incidentalomas, detected on Ga-PSMA PET/CT, can reveal more clinically significant extraprostatic disorders.