Is 177Lu-PSMA an effective treatment modality for mCRPC patients with bone and visceral metastasis?

OBJECTIVE: We analyzed the clinical outcome of lutetium-177 prostate-specific membrane antigen (177Lu-PSMA) in metastatic castration-resistant prostate cancer (mCRPC) patients with visceral metastasis. SUBJECTS AND METHODS: Ten patients of mCRPC with visceral metastasis were enrolled for one cycle of 177Lu-PSMA therapy. Number of efficacy and safety parameters, e.g., prostate-specific antigen (PSA), visual analog scale (VAS) and analgesic quantification scale (AQS), hemoglobin (Hb), total leukocytes counts (TLC), platelets, creatinine, & total bilirubin, were assessed and compared with Wilcoxon signed-rank test. The progression-free survival (PFS) curve was computed by the Kaplan-Meier method. The receiver operating characteristic curve (ROC) was also plotted for 177Lu-PSMA dose. P≤0.05 was considered significant. RESULTS: Liver (80%), lung (30%), adrenal (10%), and peritoneum (10%) were the sites of visceral metastasis in our study. On PSA response assessment, 10%, 60%, and 30% of the patients had partial response, stable disease, and progressive disease, respectively. Forty percent of the patients had improvement in the VAS, while 50% had improvement in the AQS score. Median PFS was 24 weeks in our study. A cut-off of 4.88GBq of 177Lu-PSMA was the best-predicted progression with 66.67% sensitivity and 100% specificity on ROC analysis. Thirty percent of the patients showed grade 3 anemia. No other significant toxicity was seen. CONCLUSION: Lutetium-177-PSMA was a reasonable palliative treatment option with limited toxicity for these end-stage mCRPC patients with visceral metastasis with adequate PSA stabilization. A synergistic drug amalgamation may be an ideal way to boost the outcome in the future.

Risk stratification and staging in prostate cancer with prostatic specific membrane antigen PET/CTObjective: A one-stop-shop.

OBJECTIVE: Current imaging modalities for prostate cancer (PC) had limitations for risk stratification and staging. Magnetic resonance imaging (MRI) frequently underestimated lymphatic metastasis while bone scintigraphy often had diagnostic dilemmas. Prostatic specific membrane antigen (PSMA) positron emission tomography-computed tomography (PET/CT) has been remarkable in diagnosing PC recurrence and staging. We hypothesized it can become one-stop-shop for initial risk stratification and staging. SUBJECTS AND METHOD: Ninety seven PSMA PET-CT studies were re analysed for tumor node metastases (TNM) staging and risk stratification of lymphatic and distant metastases proportion. The histopathology of 23/97 patients was available as gold standard. Chi-square test was used for proportion comparison. Sensitivity, specificity, positive predictive value (PPV), negative predictive value (NPV), over-estimation, under-estimation and correct-estimation of T and N stages were calculated. Cohen's kappa coefficient (k) was derived for inter-rater agreement. RESULTS: Lymphic or distant metastases detection on PSMA PET/CT increased significantly with increase in risk category. PSMA PET/CT sensitivity, specificity, PPV and NPV for extra prostatic extension (EPE), seminal vesicle invasion (SVI) and lymphatic metastases were 63.16%, 100%, 100%, 36.36% & 55%, 100%, 100%, 25% and 65.62%, 99.31%, 87.50%, 97.53%, respectively. Cohen's kappa coefficient showed substantial agreement between PSMA PET/CT and histopathological lymphic metastases (κ 0.734) however, it was just in fair agreement (κ 0.277) with T stage. PSMA PET/CT over-estimated, under-estimated and correct-estimated T and N stages in 8.71%, 39.13%, 52.17% and 8.71%, 4.35%, 86.96% cases, respectively. CONCLUSION: We found that PSMA PET/CT has potential for initial risk stratifications with reasonable correct estimation for N stage. However, it can underestimate T stage. Hence, we suggest that PSMA PET/CT should be used for staging and initial risk stratification of PC as one-stop-shop with regional MRI in surgically resectable cases.

Haemolytic anaemia as first manifestation of Wilson's disease: a report of two cases.

Wilson's disease can have different manifestations like jaundice, cirrhosis of liver, extrapyramidal symptoms and dementia. Haemolytic anaemia may occur but it is commonly associated with florid manifestation of liver disease. Sometimes, liver cell necrosis can release huge free copper ions in blood, giving rise to oxidant damage to erythrocytes. Oxidative damage to cell membrane, haemoglobin and erythrocyte metabolism causes haemolytic crisis. In some cases, liver involvement is subclinical, but nonetheless, free copper is released from necrosed hepatocytes and causes oxidative damage to erythrocytes.We had two cases of Wilson's disease with initial presentation as severe haemolytic anaemia and no other clinical feature suggestive of Wilson's disease was present. In unclear cause of haemolytic anaemia, especially in adolescents or young adults, Wilson's disease should be considered. As Wilson disease is rare and its initial presentation with haemolytic anaemia is rarer, high level of suspicion is required to diagnose it.

A Case Series of Neurolymphomatosis: Role of Fluorodeoxyglucose Positron Emission Tomography-Computed Tomography Scan Reiterated.

Neurolymphomatosis is rarely encountered in high-grade lymphomas. In this case series, we retrospectively analyzed six neurolymphomatosis cases to look for possible risk factors, common and uncommon presentations, and the lessons learned. Neuropathic pain was the most common symptom with mono or polyradiculopathy in this series. However, all lymphomatous infiltrated nerves diagnosed on fluorodeoxyglucose positron emission tomography-computed tomography (FDG PET/CT) were not symptomatic. The lumbar, brachial plexus, and trigeminal nerve were the most common sites and were depicted well on FDG PET/CT. Magnetic resonance imaging (MRI) of the brain better delineates cranial nerves and meningeal involvement. Cerebrospinal fluid flow cytometry was normal until meninges were involved. FDG PET/CT incrementally evaluated extra-neural disease sites, thus helping in deciding biopsy sites and further management. We concluded that a whole-body FDG PET/CT including limbs with MRI brain was the appropriate investigation for evaluating suspected neurolymphomatosis in advanced-stage diffuse large B-cell lymphoma.

Effectiveness of Head-and-Neck Molecular Imaging Reporting and Data System Criterion in Head-and-Neck Squamous Cell Carcinoma PostConcurrent Chemoradiotherapy.

Purpose: Postconcurrent chemoradiotherapy (CRT) response assessment has been challenging in locally advanced head-and-neck squamous cell carcinoma (LA-HNSCC) due to prevailing postradiation changes. Molecular response methods have been encouraging, although further clarifications and validations were needed. We tested the effectiveness of a proposed semi-quantitative molecular response criterion in these patients. Materials and Methods: Two subspecialty-trained physicians evaluated 18F-fluorodeoxyglucose positron emission tomography/computed tomography of LA-HNSCC patients (n = 83) post 3 months CRT using a five points Head and Neck Molecular Imaging-Reporting and Data System (HAN-MI-RADS) criterion. Where available, histopathology examination with clinical and imaging interpretation was taken as a reference for the disease. A diagnostic accuracy comparison was done with the existing Hopkins score. Further effectiveness was analyzed with disease-free survival (DFI) and overall survival (OS). Results: Metastasis was developed in 11/83 patients at 3 months of evaluation. Of 72 patients, 39, 2, and 31 patients had a complete response, equivocal response, and partial response as per HAN-MI-RADS. Per patient sensitivity, specificity, positive predictive value, negative predictive value, and accuracy for predicting loco-regional disease up to 1 and 2 years was 93.3%, 92.5%, 90.3%, 94.9%, 92.9%, and 84.9%, 91.9%, 90.3%, 87.2%, and 88.6% respectively. One year and two years DFI for each HAN-MI-RADS score showed a statistically significant difference while it was not for OS. The receiver operating characteristic curve analysis showed significantly better outcome predictability of HAN-MI-RADS (area under the curve [AUC] 0.884) than Hopkins (AUC 0.699). Conclusions: A five points HAN-MI-RADS criterion was found promising for response assessment with less equivocal results and statistically significant higher AUC than Hopkins for loco-regional recurrence prediction.

De Novo Extramedullary Plasmacytoma of Thyroid Cartilage.

ABSTRACT: Myeloma involving the laryngeal cartilage is rare, whereas extramedullary plasmacytoma involving only the thyroid cartilage is even rarer. No case of de novo extramedullary plasmacytoma involving thyroid cartilage has been published so far. Hence, it was a diagnostic challenge for clinicians, radiologists, and pathologists. Here, we presented a case of a 61-year-old man who had fixed right laryngeal swelling. After 18 F-FDG PET/CT, biopsy, and myeloma workup, it was found to be plasmacytoma involving the right thyroid cartilage lamina. This case highlighted the rarity of this presentation and the importance of keeping in mind this differential to lead toward diagnosis.

Oligometastasis to testis in prostate cancer: Role of gallium-68 prostate-specific membrane antigen positron-emission tomography computed tomography.

Accurate staging and restaging with early detection of recurrent site is the key for planning treatment in patients of prostate cancer. Recently, gallium-68 prostate-specific membrane antigen positron-emission tomography computed tomography (68Ga-PSMA PET/CT) has emerged as a better tool for this. Few uncommon sites of early metastasis can also be identified in addition to the other common sites. Herein, we present three cases of early metastasis to testis in prostate cancer identified on 68Ga-PSMA PET/CT scan.

Correction to: Evaluation of RECIST, PERCIST, EORTC, and MDA Criteria for Assessing Treatment Response with Ga68-PSMA PET-CT in Metastatic Prostate Cancer Patient with Biochemical Progression: a Comparative Study.

[This corrects the article DOI: 10.1007/s13139-018-0548-3.].

Pseudoprogression on 68Ga-Prostate-Specific Membrane Antigen-11 PET/CT in a Treated Glioblastoma.

After standard treatment of glioblastoma, pseudoprogression versus true progression is a clinical challenge. Indeed, to differentiate these 2 on contrast MRI (cMRI) is problematic. In recent time, Ga-prostate-specific membrane antigen-11 (Ga-PSMA) PET/CT has been suggested to have high accuracy in glioblastoma recurrence. We present a case of a 40-year-old man with right frontotemporal glioblastoma underwent surgery and radiotherapy. One month posttreatment cMRI showed a new enhancing lesion in the right hippocampal region, which was also positive on Ga-PSMA-11 PET/CT. On follow-up with conservative management, both cMRI and Ga-PSMA-11 PET/CT showed regression in new lesion, hence suggest pseudoprogression.

Role of 68Ga-Prostate-Specific Membrane Antigen PET/CT in Disease Assessment in Glioblastoma Within 48 Hours of Surgery.

Within 48 hours after surgery, disease assessment in glioblastoma is a challenge for both the clinician and the radiologist. Certain technical and logistical issues prevail in this period. Ga-prostate-specific membrane antigen PET/CT is a known molecular imaging marker in prostate cancer. Its role in high-grade gliomas has been recently discussed. We present a case of a 39-year-old man with recurrence glioblastoma of the right frontal lobe and underwent resurgery. After surgery, Ga-prostate-specific membrane antigen PET/CT showed residual disease along the posterior and inferior margin of the postoperative cavity.

Correction to: Safety Profile and Therapeutic Efficacy of One Cycle of Lu177-PSMA in End-Stage Metastatic Castration-Resistant Prostate Cancer Patients with Low Performance Status.

[This corrects the article DOI: 10.1007/s13139-019-00624-8.].

Evaluation of response in patients of metastatic castration resistant prostate cancer undergoing systemic radiotherapy with lutetium177-prostate-specific membrane antigen: A comparison between response evaluation criteria in solid tumors, positron-emission tomography response criteria in solid tumors, European organization for research and treatment of cancer, and MDA criteria assessed by gallium 68-prostate-specific membrane antigen positron-emission tomography-computed tomography.

INTRODUCTION: We evaluated various morphological and molecular response criteria in metastatic castration-resistant prostate cancer (PCa) patient undergoing peptide receptor radioligand therapy (PRLT) with Lutetium177-prostate-specific membrane antigen (PSMA) by using Gallium 68-PSMA positron-emission tomography-computed tomography (Ga68-PSMA PET-CT). METHODS: A total of 46 pre- and 8-12 weeks' post-PRLT Ga68-PSMA PET-CT studies were reanalyzed (23 comparisons). Prostate-specific antigen drop of ≥50% and ≥25% increase was considered as partial response (PR) and progressive disease (PD), respectively, for biochemical response (BR) while change in-between was considered as stable disease (SD). Response evaluation criteria in solid tumors 1.1 (RECIST 1.1) and MD Anderson (MDA) criteria for morphological response while PET response criteria in solid tumors 1.0 (PERCIST 1.0) and European organization for research and treatment of cancer (EORTC) criteria for molecular response were used. Kappa coefficient was derived to see the level of agreement. RESULTS: The proportion of PD, PR, and SD by BR and RECIST criteria was 9 (39.13%), 3 (13.04%), and 11 (47.83%) and 5 (21.74%), 2 (8.70%), and 16 (69.57%), respectively. The proportion of PD, PR, and SD was same by PERCIST and EORTC criteria and which were 8 (34.78%), 5 (21.74%), and 10 (43.48%). The proportion of PD, PR, and SD by MDA criteria was 1 (4.35%), 1 (4.35%), and 21 (91.30%), respectively. Poor agreement between BR and both morphological criteria while a statistically significant agreement with both molecular criteria seen. CONCLUSION: We concluded that molecular criteria performed better than morphological criteria in response assessment by Ga68-PSMA PET-CT in metastatic castration resistant PCa patients undergoing PRLT.

Prevalence and Predictors of "New-onset Diabetes after Transplantation" (NODAT) in Renal Transplant Recipients: An Observational Study.

OBJECTIVE: New-onset diabetes after transplantation (NODAT) develops frequently after renal transplant. The study aims at the prevalence of NODAT, predictors for developing it and therapeutic glycemic responses in NODAT. MATERIALS AND METHODS: Consecutive renal transplant recipients excluding Diabetic Kidney Disease (DKD) or pretransplant diabetes were evaluated. Forty-three out of 250 persons were found to have NODAT. Ninety age-matched transplant recipients from the rest were recruited as control. Fasting blood sugar (FBS), HbA1c, lipid profile, and trough tacrolimus level (T0) were examined in all. HOMA IR C-peptide and HOMA-beta C-peptide were calculated. RESULTS: Prevalence of NODAT in renal transplant recipients was 17.2% (43/250). Twenty-four (55.8%) developed early NODAT (<1 year) and 19 (44.2%) developed late NODAT (>1 year). Significantly higher pretransplant body mass index (BMI) (kg/m2) (P < 0.001), waist circumference (WC) (cm) (P < 0.001), pretransplant cholesterol (mg%) (P = 0.04), triglyceride (mg%) (P < 0.001), and FBS (mg%) (P < 0.001) were found in NODAT compared with non-NODAT. Trough tacrolimus (ng/mL) was found to be higher in NODAT (10.2 vs. 5.37, P < 0.001). Though HOMA IR was not found to be different between groups, HOMA-beta C-peptide was low in NODAT compared with non-NODAT (P = 0.03). Predictors of NODAT were WC [odds ratio (OR) = 01.15] and trough tacrolimus level (OR = 1.316). Best cut-off of WC for predicting NODAT was 87.5 cm for male and 83.5 cm for female. Best cut-off of T0 was 8.5 ng/mL. In NODAT, 9.3% were treated by lifestyle modification, 67.4% by oral hypoglycemic agents, 11.6% by insulin, and 11.6% by combined insulin and oral antidiabetic agents with HbA1c <7%. CONCLUSION: NODAT in renal transplant recipients is more common in those with higher pretransplant BMI, WC, pretransplant total cholesterol, triglyceride, and FBS. Beta-cell secretory defect is more relevant as etiological factor rather than insulin resistance. Higher WC and trough tacrolimus level above 8.5 ng/mL may be important factors for predicting NODAT.

Safety Profile and Therapeutic Efficacy of One Cycle of Lu177-PSMA in End-Stage Metastatic Castration-Resistant Prostate Cancer Patients with Low Performance Status.

PURPOSE: The aim of this study was to evaluate safety and therapeutic efficacy of lutetium 177 prostate-specific membrane antigen (Lu-177-PSMA) in metastatic castration-resistant prostate cancer (mCRPC) patients with low performance status. METHODS: Twenty-two patients already treated with anti-androgens and docetaxel were enrolled for one cycle of Lu-177-PSMA therapy. Haemoglobin, total leukocyte counts, platelets and serum creatinine for toxicity profile while prostate specific antigen (PSA), Eastern Cooperative Oncology Group (ECOG) performance status, visual analogue scale (VAS) and analgesic quantification scale (AQS) for therapeutic efficacy were recorded pre and 8 weeks post therapy. Wilcoxon signed-rank and ANOVA tests were used for statistical analysis. RESULTS: Partial response (PR), stable disease (SD) and progressive disease (PD) for PSA were seen in 5 (22.7%), 13 (59.1%) and 4 (18.2%) patients respectively treated with mean 6.88 GBq dose of Lu-177-PSMA. 8/22 (36.4%) patients showed ≥ 30% drop in PSA. Grade 3 haemoglobin toxicity was seen in 5/22 (22.7%) patients. No patient developed grade 4 haemoglobin toxicity. No patients had grade 3 or 4 leukocytopenia or thrombocytopenia. Wilcoxon signed-rank test showed statistical significant (P < 0.05) difference in pre and post treatment ECOG, VAS, and AQS scores. The ANOVA test showed statistically significant difference in mean doses of Lu-177-PSMA used in three PSA response groups while difference was non-significant for other variables. CONCLUSION: We concluded that Lu-177-PSMA therapy has adequate pain palliation in end-stage mCRPC patients with low performance status and it has a potential to become effective therapeutic option in properly selected patients.

Liver Functional Volumetry by Tc-99m Mebrofenin Hepatobiliary Scintigraphy before Major Liver Resection: A Game Changer.

Future remnant liver function (FRL-F) estimation is important before major liver resection to avoid posthepatectomy liver failure (PHLF). Conventionally, it is estimated by global dynamic liver function tests which assume homogeneous liver function and unable to calculate regional function. Computed tomography is another method to estimate FRL volume but assumes that volume is equivalent to function. Hence, a global and regional non-invasive liver function test is desirable. Studies were identified by MEDLINE, PubMed, and Google Scholar for articles from January 1990 to December 2017 using the following keywords "Mebrofenin, hepatobiliary scintigraphy (HBS), FRL-F, PHLF, portal vein embolization (PVE)." HBS with technetium-99 m galactosyl human serum albumin (Tc-99m GSA) and Tc-99m Mebrofenin is a known test for functional liver assessment. Restricted availability of Tc-99m GSA only in Japan is a main drawback for its global acceptance. However, Tc-99m Mebrofenin is routinely available to the rest of the world. A unique protocol for FRL-F estimation by Tc-99m Mebrofenin is described in detail in this review. Tc-99m Mebrofenin HBS has shown a strong correlation to 15 min indocyanine green clearance. HBS has been reported better in predicting the risk of PHLF with a 2.69%/min/m2 cutoff of FRL-F. Tc-99m Mebrofenin HBS has been found better in stratification of PVE before major liver surgery as well. We concluded, Tc-99m Mebrofenin HBS was unique in calculating global and regional liver function and takes nonuniformity and underlying pathology in the account. Moreover, a single cutoff might fit in all for PHLF risk assessment and PVE stratification.

Incremental value of 68-gallium-prostate-specific membrane antigen positron emission tomography/computed tomography in patients with abnormal prostate-specific antigen and benign transrectal ultrasound biopsy.

INTRODUCTION: Bladder outlet obstruction due to prostate enlargement is a common health problem in male and frequently investigated with prostate-specific antigen (PSA) and transrectal ultrasound (TRUS). TRUS-guided biopsy is critical to differentiate benign prostatic hyperplasia (BPH) or prostate cancer (PCa) even though it has been associated with false negative with reported 3%-16% incidence of PCa in BPH specimens. Prostate-specific membrane antigen positron emission tomography/computed tomography (PSMA PET/CT), a targeted molecular imaging for PCa, has showed promising results in recurrence and staging. We analyzed its role in patients with abnormal PSA and benign TRUS biopsy. MATERIAL AND METHODS: Of 558 68Ga-PSMA PET/CT performed from July 2014 to February 2017, we found six patients with abnormal PSA (range 8.2-24.2 ng/ml, median: 13.3 ng/ml) with benign 12 cores TRUS biopsy as indication. These cases were reanalyzed in detail. Spearman's rank test was used entire correlation using SPSS version 21. RESULTS: 68Ga-PSMA PET/CT showed mild diffuse tracer uptake in prostate in all patients with no focality and maximum standard uptake value normalized to body weight (SUVmax) range was 3.2-5.8 (median: 3.9). Two patients with PSA <10 ng/ml had normal 68Ga-PSMA PET/CT and underwent medical management. In other four patients with PSA >10 ng/ml, two showed metastatic disease in pelvic lymph node in both and in lung in one; hence, 68Ga-PSMA PET/CT changed these patients' management. Spearman's rank test showed no correlation with baseline PSA and SUVmax of prostate (rs -0.0287, P = 0.9571) while strong positive correlation was seen with baseline PSA and 68Ga-PSMA PET/CT scan positivity for extraprostatic disease (rs = 0.828, P = 0.042). CONCLUSIONS: 68Ga-PSMA whole-body PET/CT can provide useful incremental information in patient with high PSA and negative TRUS biopsy and has a potential to guide management in this subgroup of PCa patients.

Evaluation of RECIST, PERCIST, EORTC, and MDA Criteria for Assessing Treatment Response with Ga68-PSMA PET-CT in Metastatic Prostate Cancer Patient with Biochemical Progression: a Comparative Study.

PURPOSE: The aim of the study was to compare response evaluation criteria in solid tumours 1.1 (RECIST 1.1), positron emission tomography response criteria in solid tumours (PERCIST), European organisation for research and treatment of cancer (EORTC), and MD Anderson (MDA) criteria for response assessment by Gallium 68-prostate-specific membrane antigen positron emission tomography-computed tomography (Ga68-PSMA PET-CT) in metastatic adenocarcinoma prostate cancer (mPCa) patients with biochemical progression. METHODS: Eighty-eight mPCa patients with pre and post treatment Ga68-PSMA PET-CT were included. A ≥ 25% increase and ≥ 2 ng/ml above the nadir if prostate specific antigen (PSA) drop or ≥ 2 ng/ml above the baseline if PSA does not drop was considered as biochemical progression. RECIST 1.1 and MDA criteria for morphology and PERCIST and EORTC criteria for molecular response were investigated. Percentages of progressive disease (PD), partial response (PR), and stable disease (SD) were calculated. Chi-square test was used for statistical significance. RESULTS: Proportion of PD, SD, and PR by RECIST 1.1 and MDA criteria were 44 (50.57%), 39 (44.83%), 4 (4.6%), and 33 (39.76%), 48 (57.83%), 2 (2.41%) respectively. Proportion of PD, SD, and PR by PERCIST and EORTC criteria were 71 (80.68%), 11 (12.50%), 6 (6.82%), and 74 (84.09%), 8 (9.09%), 6 (6.82%) respectively. Chi-square test showed statistically significant (P < 0.05) higher proportion of progression detected by both molecular criteria as compare to both morphological criteria. CONCLUSION: We concluded that for Ga68-PSMA PET-CT response evaluation, molecular criteria performed better than morphological criteria in mPCa patient with PSA progression.

Initial risk stratification and staging in prostate cancer with prostatic-specific membrane antigen positron emission tomography/computed tomography: A first-stop-shop.

Current imaging for prostate cancer (PCa) had limitations for risk stratification and staging. Magnetic resonance imaging frequently underestimated lymph node metastasis while bone scintigraphy often had diagnostic dilemmas. Prostatic-specific membrane antigen (PSMA) positron emission tomography-computed tomography (PET/CT) has been remarkable in PCa recurrence. Ninety-seven PSMA PET-CT scans were reanalyzed for tumor node metastases staging and risk stratification of lymph node and distant metastasis proportion. Histopathology of 23/97 patients was available as gold standard. Chi-square test was used for proportion comparison. Sensitivity, specificity, positive predictive value (PPV), negative predictive value (NPV), overestimation, underestimation, and correct estimation of T and N stages were calculated. Kappa coefficient (κ) was derived for inter-rater agreement. Lymph node or distant metastasis detection on PSMA PET/CT increased significantly with increase in risk category. PSMA PET/CT sensitivity, specificity, PPV, and NPV for extraprostatic extension, seminal vesicle invasion, and lymph node metastases were 63.16%, 100%, 100%, 36.36%; 55%, 100%, 100%, 25%; and 65.62%, 99.31%, 87.50%, and 97.53%, respectively. Kappa coefficient showed substantial agreement between PSMA PET/CT and histopathological lymph node metastases (κ = 0.734); however, it was just in fair agreement (κ = 0.277) with T stage. PSMA PET/CT overestimated, underestimated, and correct estimated T and N stages in 8.71%, 39.13%, 52.17% and 8.71%, 4.35%, and 86.96% cases, respectively. PSMA PET/CT has potential for initial risk stratification with reasonable correct N stage estimation, however underestimates T stage. Hence, we concluded that PSMA PET/CT should be used as " first-stop-shop" for staging and initial risk stratification of PCa with regional magnetic resonance imaging in surgically resectable cases.

Metastasis in urothelial carcinoma mimicking prostate cancer metastasis in Ga-68 prostate-specific membrane antigen positron emission tomography-computed tomography in a case of synchronous malignancy.

Prostate cancer is the second most common cancer in man. It commonly presents with urinary symptoms, bone pain, or diagnosed with elevated prostate-specific antigen.(PSA) levels. Correct staging and early diagnosis of recurrence by a precise imaging tool are the keys for optimum management. Molecular imaging of prostate cancer with Ga-68 prostate-specific membrane antigen.(PSMA), positron emission tomography-computed tomography.(PET-CT) has recently received significant attention and frequently used with a signature to prostate cancer-specific remark. However, this case will highlight the more cautious use of it. A-72-year-old male treated earlier for synchronous double malignancy.(invasive papillary urothelial carcinoma right ureter and carcinoma prostate) presented with rising PSA.(0.51.ng/ml) and referred for Ga-68 PSMA PET-CT, which showed a positive enlarged left supraclavicular lymph node. Lymph node biopsy microscopic and immunohistochemistry examination revealed metastatic carcinoma favoring urothelial origin. Specificity of PSMA scan to prostate cancer has been seen to be compromised in a certain situation mostly due to neoangiogenesis, and false positives emerged in renal cell cancer, differentiated thyroid cancer, glioblastoma, breast cancer brain metastasis, and paravertebral schwannomas. Understanding the causes of false positive will further enhance the confidence of interpretating PSMA scans.

Does the intensity of diffuse thyroid gland uptake on F-18 fluorodeoxyglucose positron emission tomography/computed tomography scan predict the severity of hypothyroidism? Correlation between maximal standardized uptake value and serum thyroid stimulating hormone levels.

CONTEXT: F-18 fluorodeoxyglucose (F-18 FDG) positron emission tomography/computed tomography (PET/CT) scan and hypothyroidism. AIMS: The aim was to determine whether the intensity of diffuse thyroid gland uptake on F-18 FDG PET/CT scans predicts the severity of hypothyroidism. MATERIALS AND METHODS: A retrospective analysis of 3868 patients who underwent F-18 FDG PET/CT scans, between October 2012 and June 2013 in our institution for various oncological indications was done. Out of them, 106 (2.7%) patients (79 females, 27 males) presented with bilateral diffuse thyroid gland uptake as an incidental finding. These patients were investigated retrospectively and various parameters such as age, sex, primary cancer site, maximal standardized uptake value (SUVmax), results of thyroid function tests (TFTs) and fine-needle aspiration cytology results were noted. The SUVmax values were correlated with serum thyroid stimulating hormone (S. TSH) levels using Pearson's correlation analysis. STATISTICAL ANALYSIS USED: Pearson's correlation analysis. RESULTS: Clinical information and TFT (serum FT3, FT4 and TSH levels) results were available for 31 of the 106 patients (27 females, 4 males; mean age 51.5 years). Twenty-six out of 31 patients (84%) were having abnormal TFTs with abnormal TSH levels in 24/31 patients (mean S. TSH: 22.35 µIU/ml, median: 7.37 µIU/ml, range: 0.074-211 µIU/ml). Among 7 patients with normal TSH levels, 2 patients demonstrated low FT3 and FT4 levels. No significant correlation was found between maximum standardized uptake value and TSH levels (r = 0.115, P > 0.05). CONCLUSIONS: Incidentally detected diffuse thyroid gland uptake on F-18 FDG PET/CT scan was usually associated with hypothyroidism probably caused by autoimmune thyroiditis. Patients should be investigated promptly irrespective of the intensity of FDG uptake with TFTs to initiate replacement therapy and a USG examination to look for any suspicious nodules.