The Impact of 18F-DCFPyL PET-CT Imaging on Initial Staging, Radiation, and Systemic Therapy Treatment Recommendations for Veterans With Aggressive Prostate Cancer.

PURPOSE: Our purpose was to study the effect of 2-(3-{1-carboxy-5-[(6-[18F]fluoro-pyridine-3-carbonyl)-amino]-pentyl}-ureido)-pentanedioic acid (18F-DCFPyL) positron emission tomography (PET)-computed tomography (CT) on staging/treatment recommendations of previously untreated prostate cancer. We report here results of a prospective single center single arm imaging trial within Veterans Affairs (Greater Los Angeles): the frequency of patients upstaged to M1 disease (primary endpoint) and the frequency of patients with change in treatment recommendations (secondary endpoint). This is the first report of prostate-specific membrane antigen PET-CT exclusive to U.S. veterans. METHODS AND MATERIALS: Veterans with Gleason ≥4 + 3, clinical stage ≥T2c, or prostate-specific antigen >10 ng/mL were eligible. Patients underwent conventional imaging (99mTc-methyl diphosphonate bone scan or 18F-NaF PET-CT; and pelvic CT or pelvic magnetic resonance imaging) in addition to 18F-DCFPyL PET-CT. The effect of 18F-DCFPyL PET-CT on treatment change was determined by applying prespecified treatment recommendations based on National Comprehensive Cancer Network guidelines and modern clinical practice. RESULTS: One hundred patients underwent 18F-DCFPyL PET-CT. Nineteen out of 84 (23%) patients initially thought to be nonmetastatic were upstaged to M1; 8/16 (50%) patients initially thought to have M1 disease were downstaged to M0. In total, 39/100 (39%) had a change in prespecified treatment recommendations, including change of radiation therapy volume/dose in 39/100 (39%) and starting abiraterone in 22/100 (22%). CONCLUSIONS: Incorporation of 18F-DCFPyL PET-CT into the initial conventional imaging workup for prostate cancer can substantially affect staging/treatment recommendations.

An asymptomatic anterior vaginal wall endometrioma, a rare manifestation of endometriosis: A case report.

A 23-year-old patient with an asymptomatic anterior vaginal wall cyst was referred to gynecology for evaluation and treatment. Preoperative assessment with physical examination and magnetic resonance (MR) imaging of the pelvis was most consistent with Gartner's cyst. Following resection of the cyst wall, histologic evaluation demonstrated endometrial glands, hemosiderin-laden macrophages and inflammation, consistent with vaginal wall endometrioma. This case highlights challenges in the diagnosis of endometriosis in the vagina and in other rare locations, possible mechanisms of development, and proposed treatments.

Focal 18F-NaF PET Prostate Activity in the Setting of Prostate Adenocarcinoma.

A 72-year-old man with a family history of prostate cancer and initial diagnosis of favorable intermediate risk prostate cancer via biopsy in 2017 elected for active surveillance. Two years later, he underwent prostate biopsy showing intermediate-risk cT1c Nx Mx lesion with Gleason score 3 + 4 = 7 (5 core positive). Transrectal ultrasound showed a prostate volume 28 mL, and the prostate-specific antigen was 8.1. Patient elected to proceed with combination radiation therapy and androgen deprivation therapy.

Quantitative metabolic profiles of 2nd and 3rd trimester human amniotic fluid using (1)H HR-MAS spectroscopy.

OBJECT: To establish and compare normative metabolite concentrations in 2nd and 3rd trimester human amniotic fluid samples in an effort to reveal metabolic biomarkers of fetal health and development. MATERIALS AND METHODS: Twenty-one metabolite concentrations were compared between 2nd (15-27 weeks gestation, N = 23) and 3rd (29-39 weeks gestation, N = 27) trimester amniotic fluid samples using (1)H high resolution magic angle spinning (HR-MAS) spectroscopy. Data were acquired using the electronic reference to access in vivo concentrations method and quantified using a modified semi-parametric quantum estimation algorithm modified for high-resolution ex vivo data. RESULTS: Sixteen of 21 metabolite concentrations differed significantly between 2nd and 3rd trimester groups. Betaine (0.00846+/-0.00206 mmol/kg vs. 0.0133+/-0.0058 mmol/kg, P < 0.002) and creatinine (0.0124+/-0.0058 mmol/kg vs. 0.247+/-0.011 mmol/kg, P < 0.001) concentrations increased significantly, while glucose (5.96+/-1.66 mmol/kg vs. 2.41+/-1.69 mmol/kg, P < 0.001), citrate (0.740+/-0.217 mmol/kg vs. 0.399+/-0.137 mmol/kg, P < 0.001), pyruvate (0.0659+/-0.0103 mmol/kg vs. 0.0299+/-0.286 mmol/kg, P < 0.001), and numerous amino acid (e.g. alanine, glutamate, isoleucine, leucine, lysine, and valine) concentrations decreased significantly with advancing gestation. A stepwise multiple linear regression model applied to 50 samples showed that gestational age can be accurately predicted using combinations of alanine, glucose and creatinine concentrations. CONCLUSION: These results provide key normative data for 2nd and 3rd trimester amniotic fluid metabolite concentrations and provide the foundation for future development of magnetic resonance spectroscopy (MRS) biomarkers to evaluate fetal health and development.

(1)H HR-MAS spectroscopy for quantitative measurement of choline concentration in amniotic fluid as a marker of fetal lung maturity: inter- and intraobserver reproducibility study.

PURPOSE: To determine the intra- and interobserver reproducibility of human amniotic fluid metabolite concentration measurements (including potential markers of fetal lung maturity) detectable by MR spectroscopy. MATERIALS AND METHODS: (1)H high-resolution magic angle spinning (HR-MAS) spectroscopy was performed at 11.7 T on 23 third-trimester amniotic fluid samples. Samples were analyzed quantitatively using 3-(trimethylsilyl)propionic-2,2,3,3-d(4) acid (TSP) as a reference. Four observers independently quantified eight metabolite regions (TSP, lactate doublet and quartet, alanine, citrate, creatinine, choline, and glucose) twice from anonymized, randomized spectra using a semiautomated software program. RESULTS: Excellent inter- and intraobserver reproducibility was found for all metabolites. Intraclass correlation as a measure of interobserver agreement for the four readers ranged from 0.654 to 0.995. A high correlation of 0.973 was seen for choline in particular, a major component of surfactant. Pearson correlation as a measure of intraobserver reproducibility ranged from 0.478 to 0.999. CONCLUSION: Quantification of choline and other metabolite concentrations in amniotic fluid by high-resolution MR spectroscopy can be performed with high inter- and intraobserver reproducibility. Demonstration of reproducible metabolite concentration measurements is a critical first step in the search for biomarkers of fetal lung maturity.

In vivo (1)H magnetic resonance spectroscopy of amniotic fluid and fetal lung at 1.5 T: technical challenges.

PURPOSE: To identify the major technical challenges associated with in utero single-voxel proton spectroscopy of amniotic fluid and fetal lung and to evaluate the feasibility of performing in utero fetal spectroscopy for fetal lung maturity testing. MATERIALS AND METHODS: Fetal magnetic resonance (MR) spectroscopy of amniotic fluid and fetal lung were performed at 1.5 T in 8 near-term pregnant women. Presence/absence of lactate and choline peaks was tabulated. Ex vivo spectra were obtained from amniotic fluid samples to investigate and refine sequence parameters. RESULTS: Spectroscopy failed in 3 of 8 cases due to maternal discomfort (n = 1) or fetal gastroschisis (n = 2). Both fetal motion and low signal-to-noise ratio were limiting factors for the remaining 5 clinical in vivo studies at 1.5 T. Ex vivo and in vivo studies suggested feasibility for detecting lactate from amniotic fluid within a reasonable clinical scan time (4-5 minutes). Lactate was detected in 3 of 5 patients. Choline detection was limited and was detected in 1 patient. CONCLUSION: Minor motion effects can be overcome but continuous fetal motion is problematic. Lactate detection seems clinically feasible, but choline detection requires additional technical development and, potentially, further imaging at a higher field strength because of the low signal-to-noise ratio at 1.5 T.

Review of atypical pelvic masses on CT and MRI: expanding the differential diagnosis.

Pelvic masses are increasingly evaluated by computed tomography and magnetic resonance imaging. Existing literature predominantly addresses common bladder, prostate, or gynecologic masses, with scant radiologic literature on less common pelvic masses. This article highlights the imaging features of some uncommon pelvic masses and emphasizes findings of particular diagnostic or clinical utility. Certain imaging findings can suggest specific diagnoses or can narrow the differential diagnosis.