Magnetic resonance imaging-guided renal biopsy shows high safety and diagnostic yield: a tertiary cancer center experience.

OBJECTIVES: To evaluate the technical success and outcomes of renal biopsies performed under magnetic resonance imaging (MRI) using a closed-bore, 1.5-Tesla MRI unit. MATERIALS AND METHODS: We retrospectively reviewed our institutional biopsy database and included 150 consecutive MRI-guided biopsies for renal masses between November 2007 and March 2020. We recorded age, sex, BMI, tumor characteristics, RENAL nephrometry score, MRI scan sequence, biopsy technique, complications, diagnostic yield, pathologic outcome, and follow-up imaging. Univariate logistic regression was used to assess the association between different parameters and the development of complications. McNemar's test was used to assess the association between paired diagnostic yield measurements for fine-needle aspiration and core samples. RESULTS: A total of 150 biopsies for 150 lesions were performed in 150 patients. The median tumor size was 2.7 cm. The median BMI was 28.3. The lesions were solid, partially necrotic/cystic, and predominantly cystic in 137, eight, and five patients, respectively. Image guidance using fat saturation steady-state free precession sequence was recorded in 95% of the biopsy procedures. Samples were obtained using both fine-needle aspiration (FNA) and cores in 99 patients (66%), cores only in 40 (26%), and FNA only in three (2%). Tissue sampling was diagnostic in 144 (96%) lesions. No major complication developed following any of the biopsy procedures. The median follow-up imaging duration was 8 years and none of the patients developed biopsy-related long-term complication or tumor seeding. CONCLUSIONS: MRI-guided renal biopsy is safe and effective, with high diagnostic yield and no major complications. CLINICAL RELEVANCE STATEMENT: Image-guided renal biopsy is safe and effective, and should be included in the management algorithm of patients with renal masses. Core biopsy is recommended. KEY POINTS: • MRI-guided biopsy is a safe and effective technique for sampling of renal lesions. • MRI-guided biopsy has high diagnostic yield with no major complications. • Percutaneous image-guided biopsy plays a key role in the management of patients with renal masses.

Development of a Novel Comprehensive Hepatocellular Carcinoma Outcome Prognostic Scoring System With Integration of Imaging Features.

BACKGROUND: Accurate prognostic stratification of hepatocellular carcinoma (HCC) is vital for clinical trial enrollment and treatment allocation. Multiple scoring systems have been created to predict patient survival, but no standardized scoring systems account for radiologic tumor features. We sought to create a generalizable scoring system for HCC which incorporates standardized radiologic tumor features and more accurately predicts overall survival (OS) than established systems. METHODS: Clinicopathologic parameters were collected from a prospectively collected cohort of patients with HCC treated at a single institution. Imaging studies were evaluated for tumor characteristics. Patients were randomly divided into a training set for identification of covariates that impacted OS and a validation set. Cox models were used to determine the association of various factors with OS and a scoring system was created. RESULTS: We identified 383 patients with HCC with imaging and survival outcomes, n = 255 in the training set and 128 in the validation cohort. Factors associated with OS on multivariate analysis included: tumor margin appearance on CT or MRI (hazard ratio [HR] 1.37, 95% CI, 1.01-1.88) with infiltrative margins portending worse outcomes than encapsulated margins, massive tumor morphology (HR 1.64, 95% CI, 1.06-2.54); >2 lesions (HR 2.06, 95% CI, 1.46-2.88), Child-Turcotte-Pugh class C (HR 3.7, 95% CI, 2.23-6.16), and portal vein thrombus (HR 2.41, 95% CI, 1.71-3.39). A new scoring system was developed and more predictive of OS than other well-established systems. CONCLUSIONS: Incorporation of standardized imaging characteristics to established clinical and lab predictors of outcome resulted in an improved predictive scoring system for patients with HCC.

Outcomes of Radiofrequency Ablation for Solitary T1a Renal Cell Carcinoma: A 20-Year Tertiary Cancer Center Experience.

BACKGROUND: The aim is to determine the long-term oncologic and survival outcomes of the radiofrequency ablation (RFA) of solitary de novo T1a renal cell carcinoma (RCC). MATERIALS AND METHODS: We retrospectively reviewed our renal ablation registry and included only patients with new solitary, biopsy-proven T1a RCC (<4 cm) who underwent RFA from January 2001 through December 2020. We collected patient and tumor characteristics. Survival rates were estimated using the Kaplan-Meier method. RESULTS: Of the 243 patients who met our inclusion criteria (160 male and 83 female, median age 68 years), 128 (52.6%) had another primary malignancy other than renal malignancy. Two-hundred forty-three RFA procedures were performed for 243 renal tumors of a median tumor size of 2.5 cm. The median follow-up period was 3.7 years. Most tumors (68.6%) were clear cell RCC. Ten patients (4.1%) experienced Clavien-Dindo Grade III complications. Seven patients(3.1%) developed recurrence at the ablation zone, and 11 (4.5%) developed recurrence elsewhere in the kidney. The 15-year local-recurrence- and disease-free survival were 96.5% and 88.6%, respectively. The 15-year metastasis-free survival and cancer-specific survival were 100%. CONCLUSIONS: RFA is a highly effective modality for the management of T1a RCC, with low complication and recurrence rates. Long-term data revealed favorable oncologic and survival outcomes.

Rate of incidental central nervous system meningioma detected in patients undergoing 18F-fluciclovine PET/CT imaging for evaluation of prostate cancer.

OBJECTIVE: To evaluate the rate of incidental detection of central nervous system (CNS) meningioma in patients undergoing 18F-fluciclovine PET/computed tomography (CT) imaging for the evaluation of prostate cancer. METHODS: The reports of 850 18F-fluciclovine PET/CT scans in 566 patients with pathologically proven prostate cancer performed from April 2017 to July 2019, were retrospectively reviewed for the presence of CNS meningioma. RESULTS: A total of 14 patients (2.8%) (age range: 54-82 years old) had abnormal focal intracranial 18F-fluciclovine uptake, all extra-axial in location (SUVmax range: 3.2-19.3). Two cases out of 14 (0.35%) were diagnosed as metastatic lesions. Twelve out of the 14 patients, had 18F-fluciclovine PET/CT imaging findings suspicious for CNS meningioma, 2 of them received another diagnosis on further imaging, and only 10 cases (2%) had the diagnosis of meningioma according to follow-up MRI and 18F-fluciclovine PET/CT. CONCLUSION: Focal 18F-fluciclovine avid intracranial lesions incidentally detected in patients undergoing PET/CT imaging for prostate cancer are most often CNS meningiomas.

Incidental 18F-Fluciclovine Uptake in a Desmoid Tumor Detected in a Patient Undergoing PET/CT Imaging for Prostate Cancer.

ABSTRACT: A 74-year-old man with biochemical recurrent prostate cancer underwent 18F-fluciclovine PET/CT for restaging to determine subsequent treatment strategy. 18F-fluciclovine PET/CT imaging demonstrated incidental focal heterogeneous increased 18F-fluciclovine uptake corresponding to a soft tissue nodule within the musculature of the left anterior abdominal wall. Subsequent ultrasound-guided biopsy of the lesion revealed histopathology compatible with a desmoid tumor. Consequently, the patient underwent surgical resection with wide local excision of the lesion.

Prostate Cancer Liver Metastases Presenting as Relatively Photopenic Lesions on 18F-Fluciclovine PET/CT.

ABSTRACT: A 66-year-old man with prostate adenocarcinoma status post radical retropubic prostatectomy and bilateral pelvic lymph node dissection, followed by salvage external beam radiation therapy to the prostate bed 1 year after surgery. Over the course of 17 years, the patient underwent multiple lines of systemic treatment for recurrent disease. He was referred for restaging 18F-fluciclovine PET/CT due to rising serum prostate-specific antigen levels. Contrast-enhanced 18F-fluciclovine PET/CT images demonstrated multiple new liver metastases, which were relatively photopenic in comparison with the physiologic radiotracer activity in the surrounding normal liver parenchyma.

Morison's pouch: anatomical review and evaluation of pathologies and disease spread on cross-sectional imaging.

The peritoneum is a complex structure. Having a better understanding of this complex anatomy will enable the radiologist to accurately assess and diagnose the wide range of intra-abdominal pathologies. In this article, we review the anatomy, boundaries, and connections of Morison's pouch. In addition, we discuss the incidence and development of common pathological conditions within Morison's pouch and the role of multiple imaging modalities in assessment and diagnosis of these conditions.

Characterization of pediatric head and neck masses with quantitative analysis of diffusion-weighted imaging and measurement of apparent diffusion coefficients.

PURPOSE: Our objective was to investigate the accuracy of quantitative diffusion-weighted imaging (DWI) to determine the histopathologic diagnosis of pediatric head and neck lesions. MATERIALS AND METHODS: This retrospective study included 100 pediatric patients recently diagnosed with head and neck tumors. All patients underwent preoperative conventional magnetic resonance imaging (MRI) and DWI. Each lesion was evaluated according to signal characteristics, enhancement pattern, and diffusivity. The average apparent diffusion coefficient (ADC) obtained from each tumor was compared to the histological diagnosis of benign, locally malignant, or malignant categories. RESULTS: Our retrospective study showed a significant negative correlation between average ADC and tumor histopathologic diagnosis (P < 0.001, r = -0.54). The mean ADC values of benign, locally malignant lesions, and malignant tumors were 1.65 ± 0.58 × 10-3, 1.43 ± 0.17 × 10-3, and 0.83 ± 0.23 × 10-3 mm2 s-1, respectively. The ADC values of benign and locally malignant lesions were overlapped. We found a cut-off value of ≥1.19 × 10-3 mm2s-1 to differentiate benign from malignant pediatric head and neck masses with a sensitivity of 97.3%, specificity of 80.0%, positive predictive value of 94.7%, and negative predictive value of 88.9%. CONCLUSION: Diffusion-weighted MRI study is an accurate, fast, noninvasive, and nonenhanced technique that can be used to characterize head and neck lesions. DWI helps to differentiate malignant from benign lesions based on calculated ADC values. Additionally, DWI is helpful to guide biopsy target sites and decrease the rate of unnecessary invasive procedures.

Cushing Syndrome: Diagnostic Workup and Imaging Features, With Clinical and Pathologic Correlation.

OBJECTIVE: Cushing syndrome (CS) is a constellation of clinical signs and symptoms resulting from chronic exposure to excess cortisol, either exogenous or endogenous. Exogenous CS is most commonly caused by administration of glucocorticoids. Endogenous CS is subdivided into two types: adrenocorticotropic hormone (ACTH) dependent and ACTH independent. CONCLUSION: Cushing disease, which is caused by a pituitary adenoma, is the most common cause of ACTH-dependent CS for which pituitary MRI can be diagnostic, with bilateral inferior petrosal sinus sampling useful in equivocal cases. In ectopic ACTH production, which is usually caused by a tumor in the thorax (e.g., small cell lung carcinoma, bronchial and thymic carcinoids, or medullary thyroid carcinoma) or abdomen (e.g., gastroenteropancreatic neuroendocrine tumors or pheochromocytoma), CT, MRI, and nuclear medicine tests are used for localizing the source of ACTH. In ACTH-independent CS, which is caused by various adrenal abnormalities, adrenal protocol CT or MRI is usually diagnostic.

Outcomes of Patients With Metastatic Non-Clear-Cell Renal Cell Carcinoma Treated With Pazopanib.

BACKGROUND: Pazopanib is associated with increased progression-free survival (PFS) in clear-cell renal cell carcinoma (RCC) and has become a standard of care in this disease. The drug is used in metastatic non-clear-cell RCC, but data on outcomes in this setting are limited. PATIENTS AND METHODS: We conducted a retrospective data analysis of records of consecutive metastatic non-clear-cell RCC patients who received pazopanib in front-line and salvage settings between November 2009 and November 2012. Tumor response rate was assessed by a blinded radiologist using Response Evaluation Criteria in Solid Tumors version 1.1. PFS and overall survival (OS) times were estimated using Kaplan-Meier methods. RESULTS: Twenty-nine patients were identified with non-clear-cell metastatic RCC, 9 received pazopanib in the front-line setting, 20 in the salvage setting after progression of disease with other targeted therapies. Seven patients (24%) had papillary RCC, 4 (14%) had chromophobe, 5 (17%) had unclassified histopathology, and 13 (45%) had other subtypes including collecting duct, translocation Xp11.2, and various subtypes with sarcomatoid differentiation. All patients discontinued pazopanib before analysis. Median PFS was 8.1 months (95% CI, 5.7-NA [not available]) in the front-line group, and 4 months (95% CI, 2.1-9.9) in the salvage group. Median OS was 31 months (95% CI, 9.2-NA) in the front-line group, and 13.6 months (95% CI, 6.4-NA) in the salvage group. CONCLUSION: Pazopanib showed efficacy in patients with metastatic non-clear-cell RCC in the front-line and salvage settings. Toxicity was mild to moderate and manageable. Further studies are needed to evaluate pazopanib's role in non-clear-cell RCC in terms of efficacy and safety.

(18)F-FDG Uptake at the Surgical Margin after Hepatic Resection: Patterns of Uptake and Differential Diagnosis.

OBJECTIVE: To evaluate the patterns of (18)F-FDG uptake at the surgical margin after hepatectomy to identify features that may differentiate benign and malignant uptake. METHODS: Patients who had undergone a PET/CT after hepatectomy were identified. Delay between resection and PET/CT, presence of uptake at the surgical margin, pattern of uptake, and maximal standardized value were recorded. The PET/CT findings were correlated with contrast-enhanced CT or MRI. RESULTS: There were 26 patients with increased 18F-FDG uptake; uptake was diffuse in seven and focal in 19. Diffuse uptake was due to inflammation in all cases. Focal uptake was due to recurrence in 12 and inflammation in seven cases. Defining a focal pattern only as a positive for malignancy yielded 100 % sensitivity, 87 % specificity, 37 % false positive rate. As expected, SUVmax was significantly higher for recurrence than inflammation, but did overlap. Contrast-enhanced CT allowed differentiation between malignant and benign uptake in all cases. CONCLUSION: F-FDG uptake after hepatectomy does not equate to recurrence and yields a high false positive rate. Diffuse uptake did not require additional evaluation in our sample. Focal uptake, however, may be due to recurrence; differentiating benign and malignant nodular uptake relies on optimal contrast-enhanced CT or MRI. KEY POINTS: • Marginal uptake exposes patients to the risk of false positive diagnosis of recurrence. • Benign and malignant patterns of marginal uptake overlap. • Diffuse marginal uptake in our experience, has a high chance to be inflammatory. • Focal marginal uptake can be due to recurrent tumour or inflammation. • Contrast-enhanced CT or MR allows the differentiation between benign and malignant uptake.