Magnetic resonance (MR) imaging is an important imaging technique in the evaluation of scrotal masses, providing a useful adjunct to ultrasonography (US). Although US is the modality of choice for initial evaluation of scrotal pathologic conditions because of its wide availability, low cost, and high sensitivity for detection of testicular and paratesticular disease processes, US findings may occasionally be inconclusive. MR imaging may provide additional information in these cases, often affecting patient management. This article reviews and illustrates the MR imaging features of solid extratesticular and intratesticular benign and malignant scrotal tumors, as well as nonneoplastic lesions that can mimic neoplasia. Normal scrotal MR anatomic features and optimal MR imaging technique are also presented.

The spread of pelvic tumors to lymph nodes is an important means of tumor dissemination. Nodal metastases have important management and prognostic impact. Pelvic tumors usually metastasize first to regional lymph nodes, which are specific groups of nodes for each tumor, and are classified according to the TNM system as N-stage disease. If a pelvic tumor spreads to a lymph node outside of the defined regional nodes, this is considered M-stage disease, which usually results in upstaging of the disease to overall stage IV cancer and may potentially affect the patient's treatment options. Knowledge of the regional nodal spread of each tumor is essential in formulating effective search strategies for cross-sectional imaging studies performed for staging. Also important is correct description of the nomenclature of nodal metastases to facilitate proper staging. In this review, the patterns of regional nodal spread and N-stage classification are presented for carcinomas of the anus, bladder, cervix, endometrium, ovary, penis, prostate, rectum, testis, vagina, and vulva. Pelvic lymph node anatomy and nomenclature are reviewed with schematic illustrations and clinical examples from patients with pelvic tumors.

Neuroblastoma (NB) is a common childhood malignant tumor of the neural crest-derived sympathetic nervous system. In NB the frequent loss of heterozygosity (LOH) on chromosome 1p raises the possibility that this region contains tumor-suppressor genes whose inactivation contributes to tumorigenesis. The human homolog of the Drosophila neural fate determination gene CASZ1, a zinc-finger transcription factor, maps to chromosome 1p36.22, a region implicated in NB tumorigenesis. Quantitative real-time PCR analysis showed that low-CASZ1 expression is significantly correlated with increased age (Z18 months), Children's Oncology Group high-risk classification, 1p LOH and MYCN amplification (all Po0.0002) and decreased survival probability (P ¼ 0.0009). CASZ1 was more highly expressed in NB with a differentiated histopathology (Po0.0001). Retinoids and epigenetic modification agents associated with regulation of differentiation induced CASZ1 expression. Expression profiling analysis revealed that CASZ1 regulates the expression of genes involved in regulation of cell growth and developmental processes. Specific restoration of CASZ1 in NB cells induced cell differentiation, enhanced cell adhesion, inhibited migration and suppressed tumorigenicity. These data are consistent with CASZ1 being a critical modulator of neural cell development, and that somatically acquired disruption of normal CASZ1 expression contributes to the malignant phenotype of human NB.

The purpose of this study was to compare hyperpolarized 3helium magnetic resonance imaging (3He MRI) of the lungs in adults with cystic fibrosis (CF) with high-resolution computed tomography (HRCT) and spirometry. Eight patients with stable CF prospectively underwent 3He MRI, HRCT, and spirometry within 1 week. Three-dimensional (3D) gradient-echo sequence was used during an 18-s breath-hold following inhalation of hyperpolarized 3He. Each lung was divided into six zones; 3He MRI was scored as percentage ventilation per lung zone. HRCT was scored using a modified Bhalla scoring system. Univariate (Spearman rank) and multivariate correlations were performed between 3He MRI, HRCT, and spirometry. Results are expressed as mean+/-SD (range). Spirometry is expressed as percent predicted. There were four men and four women, mean age = 31.9+/-9 (20-46). Mean forced expiratory volume in 1 s (FEV)1 = 52%+/-29 (27-93). Mean 3He MRI score = 74%+/-25 (55-100). Mean HRCT score = 48.8+/-24 (13.5-83). The correlation between 3He MRI and HRCT was strong (R = +/-0.89, p < 0.001). Bronchiectasis was the only independent predictor of 3He MRI; 3He MRI correlated better with FEV1 and forced vital capacity (FVC) (R = 0.86 and 0.93, p < 0.01, respectively) than HRCT (R = +/-0.72 and +/-0.81, p < 0.05, respectively). This study showed that 3He MRI correlates strongly with structural HRCT abnormalities and is a stronger correlate of spirometry than HRCT in CF.