Diverse PSMA expression in primary prostate cancer: reason for negative [68Ga]Ga-PSMA PET/CT scans? Immunohistochemical validation in 40 surgical specimens.

PURPOSE: The purpose of this study was to immunohistochemically validate the primary tumor PSMA expression in prostate cancer (PCa) patients imaged with [68Ga]Ga-PSMA PET/CT prior to surgery, with special consideration of PET-negative cases. METHODS: The study included 40 men with newly diagnosed treatment-naïve PCa imaged with [68Ga]Ga-PSMA I&T PET/CT as part of the diagnostic work-up prior to radical prostatectomy. All primary tumors were routinely stained with H&E. In addition, immunohistochemical staining of PSMA was performed and the immunoreactive score (IRS) was computed as semiquantitative measure. Subsequently, imaging findings were correlated to histopathologic results. RESULTS: Eighty-three percent (33/40) of patients presented focal uptake of [68Ga]Ga-PSMA I&T in the primary tumor in at least one prostate lobe. Among PSMA-PET positive patients, one-third had lymph node metastases (LNM) detected by post-operative histopathology, while in PET negative patients, only 1 out of 7 presented with regional LN involvement; PSMA-avid distant lesions, predominantly in bones, were observed in 15% and 0% of patients, respectively. The median IRS classification of PSMA expression in tumor tissue was 2 (range, 1-3) both in PSMA-PET positive and negative prostate lobes, with significantly different interquartile range: 2-3 vs. 2-2, respectively (p = 0.03). The median volume of PSMA-PET positive tumors was 5.4 mL (0.2-32.9) as compared to 1.6 mL (0.3-18.3) of PET-negative tumors (p < 0.001). There was a significant but weak correlation between SUVmax and percentage of PSMA-positive tumor cells (r = 0.46, p < 0.001). A total of 35/44 (~80%) lobes were positive in PSMA-PET imaging, when a cut-off percentage of PSMA-positive cells was ≥ 90%, while 19/36 (~53%) lobes with < 90% PSMA-positive cells were PSMA-PET negative. CONCLUSION: Positive [68Ga]Ga-PSMA I&T PET/CT scan of primary tumor of PCa results from a combination of factors, such as homogeneity and intensity of PSMA expression, tumor volume and grade, with a cutoff value of ≥ 90% PSMA-positive cells strongly determining PET-positivity. Focal accumulation of [68Ga]Ga-PSMA in the primary tumor may correlate positively with aggressiveness of prostate cancer, harboring higher risk of regional LN involvement and distant metastatic spread.

Mild poikilocapnic hypoxia increases very low frequency haemoglobin oxygenation oscillations in prefrontal cortex.

BACKGROUND: The aim of the study was to investigate the effect of mild cerebral hypoxia on haemoglobin oxygenation (HbO2), cerebrospinal fluid dynamics and cardiovascular physiology. To achieve this goal, four signals were recorded simultaneously: blood pressure, heart rate / electrocardiogram, HbO2 from right hemisphere and changes of subarachnoid space (SAS) width from left hemisphere. Signals were registered from 30 healthy, young participants (2 females and 28 males, body mass index = 24.5 ± 2.3 kg/m2, age 30.8 ± 13.4 years). RESULTS: We analysed the recorded signals using wavelet transform and phase coherence. We demonstrated for the first time that in healthy subjects exposed to mild poikilokapnic hypoxia there were increases in very low frequency HbO2 oscillations (< 0.052 Hz) in prefrontal cortex. Additionally, SAS fluctuation diminished in the whole frequency range which could be explained by brain oedema. CONCLUSIONS: Consequently the study provides insight into mechanisms governing brain response to a mild hypoxic challenge. Our study supports the notion that HbO2 and SAS width monitoring might be beneficial for patients with acute lung disease.

Coupling between Blood Pressure and Subarachnoid Space Width Oscillations during Slow Breathing.

The precise mechanisms connecting the cardiovascular system and the cerebrospinal fluid (CSF) are not well understood in detail. This paper investigates the couplings between the cardiac and respiratory components, as extracted from blood pressure (BP) signals and oscillations of the subarachnoid space width (SAS), collected during slow ventilation and ventilation against inspiration resistance. The experiment was performed on a group of 20 healthy volunteers (12 females and 8 males; BMI=22.1±3.2 kg/m2; age 25.3±7.9 years). We analysed the recorded signals with a wavelet transform. For the first time, a method based on dynamical Bayesian inference was used to detect the effective phase connectivity and the underlying coupling functions between the SAS and BP signals. There are several new findings. Slow breathing with or without resistance increases the strength of the coupling between the respiratory and cardiac components of both measured signals. We also observed increases in the strength of the coupling between the respiratory component of the BP and the cardiac component of the SAS and vice versa. Slow breathing synchronises the SAS oscillations, between the brain hemispheres. It also diminishes the similarity of the coupling between all analysed pairs of oscillators, while inspiratory resistance partially reverses this phenomenon. BP-SAS and SAS-BP interactions may reflect changes in the overall biomechanical characteristics of the brain.

68Ga-PSMA I&T PET/CT for primary staging of prostate cancer.

PURPOSE: The present study is based on a retrospective analysis of Gallium-68 (68Ga)-labelled prostate-specific membrane antigen (68Ga-PSMA I&T) PET/CT performed in newly diagnosed, treatment-naïve prostate cancer (PCa) patients prior to definitive treatment. METHODS: A total of 82 men were included in the study and were imaged with 68Ga-PSMA I&T PET/CT to assess the distribution of PSMA-avid disease for staging purposes (11 with low-risk, 32 with intermediate-risk, and 39 with high-risk PCa). Forty patients (20 with intermediate- and 20 with high-risk disease) underwent subsequent radical prostatectomy with extended pelvic lymph node dissection which allowed for correlation of imaging findings with histopathologic data. RESULTS: PSMA-positive disease was detected in 83% of patients with 66/82 (80.5%) primary tumours being visualized. PSMA-avid lymph nodes were recorded in 17/82 patients (20.7%, 3 with intermediate-risk and 14 with high-risk PCa); distant disease was found in 14/82 subjects (17.1%, 2 with intermediate-risk and 12 with high-risk PCa). No extraprostatic disease was found in low-risk PCa. SUVmax of primary tumours showed a weak but significant correlation with serum PSA values (r = 0.51, p < 0.001) and Gleason scores (GSC; r = 0.35, p = 0.001), respectively. In correlation with histopathology, calculated per-region sensitivity, specificity, positive predictive value, negative predictive value, and accuracy for detection of lymph node metastases were 35.0%, 98.4%, 63.6%, 95.0%, and 93.0%, respectively. CONCLUSIONS: In patients with initial diagnosis of intermediate- and high-risk prostate cancer, 68Ga-PSMA I&T PET/CT emerges as a relevant staging procedure by identifying nodal and/or distant metastases. Due to the low prevalence of extraprostatic disease, its value seems to be limited in low-risk disease.

Carotid Artery Stenting and Blood-Brain Barrier Permeability in Subjects with Chronic Carotid Artery Stenosis.

Failure of the blood-brain barrier (BBB) is a critical event in the development and progression of diseases such as acute ischemic stroke, chronic ischemia or small vessels disease that affect the central nervous system. It is not known whether BBB breakdown in subjects with chronic carotid artery stenosis can be restrained with postoperative recovery of cerebral perfusion. The aim of the study was to assess the short-term effect of internal carotid artery stenting on basic perfusion parameters and permeability surface area-product (PS) in such a population. Forty subjects (23 males) with stenosis of >70% within a single internal carotid artery and neurological symptoms who underwent a carotid artery stenting procedure were investigated. Differences in the following computed tomography perfusion (CTP) parameters were compared before and after surgery: global cerebral blood flow (CBF), cerebral blood volume (CBV), mean transit time (MTT), time to peak (TTP) and PS. PS acquired by CTP is used to measure the permeability of the BBB to contrast material. In all baseline cases, the CBF and CBV values were low, while MTT and TTP were high on both the ipsi- and contralateral sides compared to reference values. PS was approximately twice the normal value. CBF was higher (+6.14%), while MTT was lower (-9.34%) on the contralateral than on the ipsilateral side. All perfusion parameters improved after stenting on both the ipsilateral (CBF +22.66%; CBV +18.98%; MTT -16.09%, TTP -7.62%) and contralateral (CBF +22.27%, CBV +19.72%, MTT -14.65%, TTP -7.46%) sides. PS decreased by almost half: ipsilateral -48.11%, contralateral -45.19%. The decline in BBB permeability was symmetrical on the ipsi- and contralateral sides to the stenosis. Augmented BBB permeability can be controlled by surgical intervention in humans.

US not bright but right method of thyroid volume estimation even in large and substernal extended goitres. Comparison of US and three methods of CT thyroid evaluation ­ prospective study.

BACKGROUND: Ultrasound is nowadays a method of choice for thyroid volume assessment. However, its disadvantage is some inaccuracy, which is said to be higher in huge, especially substernally extended goitres. AIMS: The aim of the study was to compare the US and CT thyroid volumetric measurements: multi-observers (CT MO) and one-observer (CT OO) to CT planimetry results (CT Pl) in patients with large goitres. MATERIALS & METHODS: The study material comprised 70 thyroid imaging examinations obtained from 35 patients with nontoxic goitres, scanned twice before and after radioiodine treatment. Mean thyroid volume was 88·97 ± 60·21 ml. Thirty-three thyroid scans revealed the extension below the jugular notch (mean of 2·46 cm). Thyroid volume in US, CT MO and CT OO was estimated using the ellipsoid formula. CT Pl was established a reference method. RESULTS: The mean thyroid volume in CT Pl was 88·97 ml (median 80·73, range 11·81 to 315·97). US underestimates thyroid volume by 7·55 ml (7·7%) with a sufficient correlation (R(2) = 0·89) and precision (20·37). CT OO is the closest and CT MO the most distant from CT Pl, with US between them in thyroid volume estimation. The percentage US bias is constant through all range of thyroid volume. There is no difference for percentage bias between US and CT Pl for goitres with (8·67%), and without (6·70%) substernal part. CONCLUSION: US examination is sufficient for epidemiological studies, radioiodine activity calculation and goitre size assessment in everyday medical practice. Neither initial size of the goitre nor its substernal extension affects US assessment precision.

Sentinel Lymph Node Biopsy in Endometrial Cancer--Comparison of 2 Detection Methods.

OBJECTIVES: Sentinel lymph node biopsy (SLNB) can identify patients with nodal metastases who are eligible for tailored treatment. The aim of study was to compare the SLN detection rates using cervical and subserosal administration of 2 tracers. RESULTS: In group 1 (82 patients), SLNB was performed using radiocolloid injected to the cervix and blue dye administered to the fundus. In group 2, blue dye was injected to cervix and fundus (106 patients). Only SLNB was performed in 128 (68.1%) women. In the remaining 60 (31.9%) patients, pelvic/para-aortic lymphadenectomy together with SLNB was performed. Groups 1 and 2 did not differ with regard to the frequencies of SLNB and lymphadenectomy. The detection rate for both groups was 90.9%. Bilateral detection was achieved in 72.5%. Para-aortic SLNs were found in 9.6%. Detection rates in groups 1 and 2 were 95.1% and 87.7% (P = 0.065). In comparison of cervical administration of radioisotope and subserosal injection of blue dye in group 1, we found a significant difference for total SLN detection (91.5% vs 74.4%, P < 0.05) and no significant difference for bilateral detection (73.3% vs 59.1%, P = 0.776). We did not find differences in the para-aortic SLN detection rates achieved after administration of a radiotracer and injection of a blue dye (4.9% vs 9.8%, P = 0.184). Eighteen patients (9.6%) presented with nodal disease, including 15 women with SLN involvement. The false-negative rate, calculated for patients subjected to lymphadenectomy, was 12.5% (1/8); using the SLNB surgical algorithm, it was 10% (1/10). CONCLUSIONS: Cervical administration of a tracer, especially radioisotope, results in high SLN detection rates. In turn, the subserosal injection can be used only as an adjuvant method for SLNB. Low para-aortic SLN detection rates observed after cervical administration of a tracer do not seem to be a serious limitation of this technique.

[Micrometastases in sentinel lymph node in endometrial cancer patients]. / Mikroprzerzuty w wartowniczym wezle chlonnym u chorych na raka endometrium.

BACKGROUND: Detection of micrometastases in sentinel lymph nodes (SLN) extends our knowledge of lymphatic spread in endometrial cancer, although its clinical significance has not yet been confirmed. OBJECTIVES: The aim of study was to determine the incidence of SLN micrometastases and to analyze the association between micrometastases and disease relapse. MATERIAL AND METHODS: Fifty-four patients with endometrioid endometrial cancer underwent routine surgical therapy and sentinel lymph node biopsy (SLNB). SLNB was performed using two techniques: cervical injection of 99mTc-labelled albumin or blue dye and fundal injection of blue dye. SLNs were subjected to ultrastaging with immunohistochemistry (AE1/AE3, 150µm). RESULTS: At least one SLN was detected in 51 patients (94.4%) and bilateral SLN detection was achieved in 80.4%. Nodal macrometastases were found in 3 patients (6.3%). SLNB enabled us to detect nodal macrometastases in 2 out of those 3 patients. In the third case, detection of SLN micrometastasis allowed to correctly determine the nodal status, thus avoiding the false negative result of SLNB. In 48 patients with detected 184 SLNs, there were 4 patients (8.3%) with micrometastases and 4 (8.3%) with ITC foci. No significant associations between the presence of risk factors (grade, myometrial invasion, cervical invasion, lymphovascular space invasion) and incidence of micrometastases and/or ITC foci in SLNs were found. CONCLUSIONS: Detection of micrometastases may result in lower false-negative rate, thus increasing SLNB safety.

Nuclear imaging of amyloidosis.

Summary Amyloidosis is a clinical condition caused by deposition of various protein fibrills in extracellular space. The presented symptoms depend on the type of deposits and the organ or organs involved. The correct diagnosis is often difficult, due to lack of nonivasive imaging techniques and insufficiency of morphological imaging procedures delievered by radiology. We presented a list of potential radiopharmaceuticals that can be used in detecting various types of amyloidoses. (123)I-SAP proved to have high sensitivity in imaging of AA and AL amyloidosis in visceral organs. (99m)Tc-Aprotinin was found to be useful in detecting cardiac amyloidosis. A couple of classical radiotracers, such as (201)Tl, (123)I-mIBG, together with (111)In-antimyosin were also tested for accuracy in cardiac imaging, however the main problem was low specificity. Potential applicability was also found in case of some bone-seeking agents and other radiotracers, e.g. (67)Ga-citrate and (99m)Tc-penta-DMSA. High sensitivity and specificity was achieved with ß2-microglobulin labeled with (131)I or (111)In. Among PET tracers, (11)C-PIB deserves more attention, because it may have an important role in diagnosing of AD in the near future. Further clinical studies are expected to take place, because noninvasive diagnosing and monitoring of amyloidosis is still a challenge.

Neuroimaging in the differential diagnosis of primary progressive aphasia - illustrative case series in the light of new diagnostic criteria.

BACKGROUND: Primary progressive aphasia (PPA) is a progressive language disorder associated with atrophy of the dominant language hemisphere, typically left. Current PPA criteria divide PPA into three variants: non-fluent (nfvPPA), semantic (svPPA) and logopenic (lvPPA). The classification of PPA into one of the three variants may be performed at 3 levels: I) clinical, II) imaging-supported, III) definite pathologic diagnosis. This paper aimed at assessing the feasibility of the imaging-supported diagnostics of PPA variants in the Polish clinical setting with access to magnetic resonance imaging (MRI) and single-photon emission computed tomography (SPECT) examinations. CASE REPORT: We present the clinical and neuroimaging data on 6 patients (4 women, 2 men) clinically diagnosed with PPA (3 with nfvPPA and 3 with lvPPA) in whom MRI and SPECT were performed in order to determine if imaging-supported diagnosis could be established in those cases. In 4 individuals (2 with nfvPPA and 2 with lvPPA) clinical diagnosis was supported by neuroimaging (SPECT, albeit not MRI), thus level II of PPA diagnosis could be established in those cases. MRI results were either inconsistent with the clinical diagnosis (Patients 1 and 2) or a mixed pattern of atrophy was observed (Patients 3-6). CONCLUSIONS: Imaging-supported diagnosis of PPA variant is more feasible with quantitative analysis of SPECT images than with purely qualitative visual analysis of MRI. Hypoperfusion abnormalities evidenced by SPECT are more variant-specific than patterns of atrophy.

[Diagnostic imaging of lying]. / Obrazowanie diagnostyczne klamstwa.

Functional diagnostic imaging has been applied in neuropsychology for more than two decades. Nowadays, the functional magnetic resonance (fMRI) seems to be the most important technique. Brain imaging in lying has been performed and discussed since 2001. There are postulates to use fMRI for forensic purposes, as well as commercially, e.g. testing the loyalty of employees, especially because of the limitations of traditional polygraph in some cases. In USA fMRI is performed in truthfulness/lying assessment by at least two commercial companies. Those applications are a matter of heated debate of practitioners, lawyers and specialists of ethics. The opponents of fMRI use for forensic purposes indicate the lack of common agreement on it and the lack of wide recognition and insufficient standardisation. Therefore it cannot serve as a forensic proof, yet. However, considering the development of MRI and a high failure rate of traditional polygraphy, forensic applications of MRI seem to be highly probable in future.

[On a border of toxicology and medical physics--atypical radiation accidents]. / Na pograniczu toksykologii i fizyki jadrowej--nietypowe wypadki radiacyjne.

The paper reviews less known radiation accidents in the history, from deadly ones to those with short-term effects. Many of them were diagnosed with notable delay, particularly ones linked to lack of knowledge or criminal actions. In physician's life, the probability to examine the victim of radiation accident is extremely low, but still exists. Therefore an adequate amount of knowledge of radiation consequences should be provided in a training curricula of medical studies and medical specialization programmes, particularly those of internal medicine and clinical toxicology, also in ones of environmental protection, environmental health and medical physics.

Advantages of hybrid SPECT-CT imaging in preoperative localization of parathyroid glands in a patient with secondary hyperparathyroidism. A case report.

BACKGROUND: Secondary hyperparathyroidism is a frequent complication of chronic renal failure. Patients resistant to pharmacotherapy are candidates for parathyroidectomy. Invasiveness of surgical treatment can be minimized by precise preoperative localization of parathyroid glands. Imaging modalities routinely used for this purpose are ultrasonography and MIBI-Tc99m scintigraphy. CASE REPORT: Our case report shows advantages of co-registered computer tomography and conventional SPECT imaging (SPECT/CT) in a patient with advanced secondary hyperparathyroidism successfully treated with surgery. RESULTS: Hybrid SPECT/CT parathyroid imaging enables better surgical planning and is superior to conventional scintigraphy.

Evaluation of usefulness of scintigraphic imaging in diagnosis of intrathecal drug delivery system malfunction - a preliminary report.

BACKGROUND: Implantable intrathecal drug delivery systems (IDDS) are basic tool enabling chronic intrathecal pharmacotherapy. Lack of expected clinical results of IDDS therapy necessitates search for the cause with the help of diagnostic imaging methods among other things. Beside radiological techniques, it is also possible to visually assess IDDS systems by nuclear medicine methods. In this study we assess utility of radioisotopic methods in differential diagnosis of failure of therapy with IDDS systems. MATERIAL/METHODS: Scintigraphic studies were performed in selected patients with neurological diseases associated with spasticity, who had IDDS system implanted and were unable to maintain satisfying clinical effect of inrathecally infused baclofen. After emptying the IDDS system of the drug, radiotracer (99mTc-DTPA) solution was injected into the pump reservoir. Subsequently, a series of scintigraphic images was registered, demonstrating passage and distribution of the infused radiotracer. RESULTS: In all investigated cases, scintigraphic study resulted in acquiring relevant additional diagnostic information. Normal or disrupted distribution of radiotracer in spinal canal allowed for a diagnosis drug resistance or demonstrated presence of arachnoid adhesions respectively. Early appearance of radiotracer in blood was considered a proof of leak. Our examinations had decisive influence on further patient treatment, allowing for diagnosis of drug resistance in one patient or complication related to IDDS system in three other cases including breakage of a catheter, pump malfunction and arachnoid adhesions. CONCLUSIONS: Scintigraphic methods carry significant amount of information facilitating final diagnosis of the cause of IDDS therapy failure. They should become an important element complementing the diagnostic strategy in patients with suspected failure of intrathecal drug administration systems. Interpretation of radioisotopic studies, since they are purely functional, must be performed in strict relation to clinical data and radiological examinations as they carry indispensable, basic information regarding morphology.

Effects of acute hypercapnia on the amplitude of cerebrovascular pulsation in humans registered with a non-invasive method.

AIM: The aim of the study was to assess non-invasively the effects of acute hypercapnia on the amplitude of cerebrovascular pulsation (CVP) in humans. METHODS: Experiments were carried out in four male volunteers aged 25, 26, 31 and 49. Changes in blood flow through the pial arteries were induced using two interventions: (A) breathing a gas mixture containing 5% CO(2) for 2 minutes and (B) intravenous administration of 1g acetazolamide. The amplitude of CVP and width of subarachnoid space (SAS) were measured non-invasively using near-infrared transillumination/backscattering sounding (NIR-T/BSS), while cerebral blood flow was assessed by single photon emission computed tomography (SPECT) and mean blood flow velocity in the left anterior cerebral artery by transcranial Doppler. RESULTS: Inhalation of a gas mixture containing 5% CO(2) evoked an increase in the amplitude of CVP (202.5% ± SE 10.1), normalized number of counts (22.6% ± SE 3.5%) and mean blood flow velocity in the left cerebral anterior artery (37.6%± SE 11.7%), while resistive index decreased (-8.7% ± SE 2.3%) and the width of SAS decreased (-8.0 ± SE 0.45). Acetazolamide also produced an increase in the amplitude of CVP (23.7% ± SE 5.4%), normalized number of counts (7.9% ± SE 1.1%), and mean blood flow velocity in the left cerebral anterior artery (62.8% ± SE 13.7%), while resistive index decreased (-7.9% ± SE 1.7%), and the width of SAS decreased (-13.4% ± SE 3.4%). CONCLUSION: Acute hypercapnia causes an increase in the amplitude of CVP pulsation in humans. NIR-T/BSS allows for non-invasive bedside monitoring of the amplitude of CVP. NIR-T/BSS is consistent with transcranial Doppler and SPECT.

[Egas Moniz: a genius, unlucky looser or a Nobel committee error?]. / Profesor Anatol Dowzenko - klinicysta neurolog, naukowiec i dydaktyk.

Portuguese neurologist António Egas Moniz is one of the most intriguing figures in the history of medicine. While an invention of angiography in 1927 is his acknowledged merit, lobotomy, invented in 1935 became a black legend of psychiatry, although sporadically it is performed also today. There are even postulates to withdraw the Nobel Prize, which Moniz received in 1949 for inventing the lobotomy. Moniz in fact re-invented lobotomy, primarily introduced in 1888 by a Swiss psychiatrist Gottlieb Burckhardt and later forgotten. Its popularisation, including its abuses was chiefly done by American neurologists Walter Freeman and James Watts. Aside the science, Moniz was an exceptionally colourful person, a merited politician, Portuguese minister of foreign affairs, the head of its delegation at Versailles in 1918, in 1951 he was even proposed a position of a President of Portugal. He was a versatile humanist and a writer, even a gambling expert. His person is hard for black and white evaluation, definitely deserving a re-evaluation from today's historical perspective.

[Medical doctors as the state presidents and prime ministers--a biographical analysis]. / Lekarze w roll prezydentów i premierów--analiza biograficzna.

The authors overviewed the biographies of 29 medical doctors who became the heads of the state or the prime ministers of their countries. Most of them ruled in a countries of fresh or unstable democracies, most often in Asia, Africa and Latin America, three of them were bloody dictators. With the exemptions of Georges Clemenceau and Sun-Yat-Sen they were not famous as historical figures, although some were good administrators like the prime minister of Norway, Gro Harlem Brundtland, Malayan prime minister Mahatir bin Mohamad, Brasilian and Chilean presidents, Juscelino Kubitschek and Veronica Bachelet. Regarding specialisation was mostly general medics or they specialised in public health.

Challenging Visualization of Sentinel Lymph Nodes in Upper Urinary Tract Urothelial Carcinoma.

PURPOSE: The purpose of this study was to assess the possibility of detecting sentinel lymph nodes (SLNs) and to perform analysis of lymphatic outflow in patients with suspicion of upper tract urothelial carcinoma (UTUC) with the use of a radioisotope-based technique. METHODS: During 2018-2021, a prospective study was conducted on 19 patients with the suspicion of UTUC and for whom diagnostic ureterorenoscopy (URS) was planned. Technetium-99m (99mTc) nanocolloid radioactive tracer injection and a tumor biopsy were performed for staging procedures. Three-dimensional (3D) reconstruction and fusion of images were performed for better localization of lymph nodes (LNs). Detection of SLNs and the analysis of the radiotracer outflow was conducted with the use of single-photon emission-computed tomography/computed tomography (SPECT/CT) lymphangiography. RESULTS: The mean age of the patients was 73.4 years; 7 (36%) were male. Pathological staging from the biopsy was T0-8 (42%), Ta-7 (36%), T1-4 (21%). SLNs were detected in two of 19 cases (10%). In one patient a single SLN (5.3%) was visualized, and in another case (5.3%), multiple (double) radioactive lymph nodes were visualized. In 17 out of the 19 (89.5%) cases, no lymphatic outflow was observed, and out of these five cases (26.3%) of gravitational leakage of injected radiotracer to the retroperitoneal space was noted. CONCLUSIONS: We demonstrated that detection of SLNs in the upper urinary tract is possible yet challenging. Radiotracer injection in the upper urinary tract during ureterorenoscopy is difficult to perform, and the expected result of injection is unsatisfactory. Lymphatic outflow from the tumor site to the first LNs in our studied group of patients is visible in 10.5% of cases. SPECT/CT lymphangiography in cases of UTUC may provide valuable information about a patient's individual anatomy of the lymphatic system and the position of the first lymph nodes draining lymph with potential metastatic cells from the tumor.

PSMA Theranostics: A "Must Have" in Every Prostate Cancer Center. Illustration of Two Clinical Cases and Review of the Literature.

This manuscript describes the history of 2 patients with prostate cancer (PCa) and the role of prostate-specific membrane antigen (PSMA) theranostics in their clinical management. In the first patient, PSMA-directed positron emission tomography (PET)/computed tomography (CT) imaging was used for primary staging of high-risk PCa before initial therapy. Then after biochemical relapse it was used to plan the scope of further treatment, in which it allowed among others to perform precise target volume delineation for salvage radiotherapy for pathologic lymph nodes. In the second patient with metastatic castration-resistant prostate cancer (mCRPC), PSMA-guided imaging played a key role in the qualification for PSMA-directed radioligand therapy (RLT) with lutetium-177. We also present a review of the current literature concerning PSMA theranostics in the 2 clinical settings, ie, primary staging of PCa and PSMA RLT of mCRPC. In the first part of the review, we report on the diagnostic efficacy of various PSMA imaging radiotracers labeled with gallium-68, fluorine-18, and technetium-99m. In the second part, we describe the limitations and future perspectives of PSMA therapeutic radiopharmaceuticals, including various beta(-) and alpha emitters.

Radionuclide-guided sentinel lymph node mapping in urachal cancer.

BACKGROUND: Urachal cancer gives metastases through the lymph nodes (LNs). No lymphadenectomy scheme in the case of this cancer exist, yet it is proposed as a staging procedure. An assessment of lymphatic outflow from the tumor site with the use of single-photon emission computed tomography/computed tomography (SPECT/CT) lymphangiography is possible for staging purposes. OBJECTIVES: To perform the mapping of the LNs draining the lymph from urachal cancer with the use of radioisotope-based technique and to propose the lymphadenectomy template in case of urachal cancer. MATERIAL AND METHODS: A prospective study was conducted in 5 patients with urachal cancer. The 99m-technetium (Tc-99m)-nanocolloid was injected during a cystoscopy prior to the surgery. Lymphangiography was performed using SPECT/CT. A radioactive LNs analysis with the use of a hand-held gamma-ray detection probe was conducted during the surgery and the sentinel lymph node (SLN) biopsy procedure was performed. An additional lymphadenectomy containing the lymphatic basin of identified radioactive LNs was performed. RESULTS: In all cases lymphatic outflow from the urachal tumor to the LNs was present. Preoperative SPECT/CT allowed detecting the activity of the radiotracer in the common iliac region in all the studied patients. In 3 cases, bilateral lymphatic outflow, and in 2 cases, unilateral lymphatic outflow was observed. All preoperatively visualized LNs were found and excised with the use of a gamma-ray detection probe during a lymphadenectomy. In all cases, SLNs did not contain metastases. CONCLUSIONS: Mapping of the LNs draining the lymph from urachal cancer with the use of radiotracer is possible. Lymphatic outflow in the case of this cancer can be both unilateral and bilateral. No recommendations about the extension of lymphadenectomy are proposed. We recommend individual assessment and treatment based on additional knowledge about lymphatic outflow. This allows for minimally invasive yet targeted treatment as an SLN basin lymphadenectomy.