Complex Cystic Lesions Research Articles

Is It Safe to Just Follow Moderately Complex Cystic Kidney Lesions

Cystic lesions of the kidney are encountered frequently as incidental findings on abdominal imaging. Nonenhancing cysts with hairline-thin walls and no

Native kidneys

A thorough understanding of the wide range of normal sonographic appearances of the kidney is vital to prevent needless concern and expense in further work-up. Variants including a dromedary hump, column of Bertin, fetal lobation, junctional parenchymal defect, extrarenal pelvises, and brightly echogenic arcuate arteries have all been confused with pathologic conditions. Once a finding has been determined to be an abnormality, characterization with respect to morphology is necessary (i.e., cystic, solid, vascularity, calcification, etc.). Simple cysts are common and readily diagnosed by ultrasound with no further work-up necessary. It is important to keep in mind, however, that not all anechoic lesions are cysts. Calyceal diverticula and vascular lesions may have a similar gray-scale appearance. Color Doppler interrogation is essential to rule out pseudoaneurysms, AV-fistulas, and AV-malformations. Complex cystic lesions often require further work-up with the differential diagnosis including cystic renal cell carcinoma, multilocular cystic nephroma (may extend into the renal pelvis), benign complex cyst, and abscess. Solid masses are considered renal cell carcinoma until proven otherwise. They are variable in echogenecity and may have areas of calcification or necrosis. Oncocytomas, angiomyolipomas, invasive transitional cell carcinoma, metastases, lymphoma, and pyelonephritis can also present as renal masses. Uniformly, hyperechoic masses can be a bit more problematic. While we typically think of hyperechoic lesions as having fat and representing angiomyolipomas, renal cell carcinoma can present in a similar fashion. All solid masses require further evaluation with either CT or MRI.

Cystic Lesions of the Breast: Sonographic-Pathologic Correlation

To understand the pathologic basis for sonographic features of cystic lesions of the breast and determine appropriate assessment and management recommendations for these lesions based on sonographic appearance. From a database of 2,072 image-guided procedures performed from July 1995 through September 2001, 150 cystic lesions were identified. Diagnosis was established with fine-needle aspiration (n = 55), 14-gauge core-needle biopsy (n = 81), or both (n = 14). Excision was performed for all malignant (n = 18) and atypical (n = 2) lesions and for 11 benign lesions, which recurred or enlarged at follow-up. Imaging follow-up was available for 92 of 119 benign lesions. Targeted sonography was performed with high-frequency (10-MHz center frequency) transducers. Imaging and histopathologic, cytologic, and/or microbiologic findings were reviewed. Lesions were categorized as simple cysts, complicated cysts (imperceptible wall, acoustic enhancement, low-level echoes), clustered microcysts, cystic masses with a thick (perceptible) wall and/or thick (> or =0.5 mm) septations, intracystic or mixed cystic and solid masses (at least 50% cystic), or predominantly solid masses with eccentric cystic foci. Of 150 lesions, 16 were simple cysts aspirated for symptomatic relief. Of 38 lesions characterized as complicated cysts and one cyst with thin septations, none proved malignant, nor did any of 16 lesions characterized as clustered microcysts. Of 23 masses with thick indistinct walls or thick septations, seven proved malignant. Of 18 intracystic or mixed cystic and solid masses, four proved malignant. Of 38 predominantly solid masses with eccentric cystic foci, seven proved malignant. Symptomatic complicated cysts generally warrant aspiration. All clustered microcysts were benign, but further study is required. Cystic lesions with thick indistinct walls and/or thick septations (> or =0.5 mm), intracystic masses, and predominantly solid masses with eccentric cystic foci should be examined at biopsy; 18 of 79 of such complex cystic lesions proved malignant in this series.

Complex renal cysts: findings on MR imaging.

We retrospectively evaluated our experience with complex cystic renal masses on MR imaging, using T1-weighted, T2-weighted, and gadolinium-enhanced images, to determine whether imaging features could permit distinction between benign and malignant lesions. Thirty-seven patients with complex cystic renal lesions were included in this retrospective study. The patients selected had undergone T1-weighted, T2-weighted, and gadolinium-enhanced MR imaging examinations using 1.5-T scanners, with at least one of the following findings: cyst fluid of heterogeneous signal intensity, mural irregularity, septa, mural masses or nodules, increased mural thickness, or intense mural enhancement. The diagnosis was established by histology in 19 patients and by follow-up studies in the remaining 18 patients. Fifty-five complex renal cystic lesions were present in the 37 patients. Among the 55 lesions, of 37 that contained fluid of a heterogeneous signal intensity, eight were malignant (22%); of 16 with irregular walls, 10 were malignant (63%); of four with septa, two were malignant (50%); of four with mural masses or nodules, three were malignant (75%); of 14 with a thick wall (>2 mm), 10 were malignant (71%); and of 32 with intense mural enhancement, 14 were malignant (44%). As independent variables, mural irregularity, mural masses or nodules, increased mural thickness, and intense mural enhancement each were highly associated with malignancy (p = .0003-.0022). The combination of mural irregularity and intense mural enhancement had the highest correlation with malignancy (p = .0002). The combination of mural irregularity and intense mural enhancement is a strong predictor of malignancy in renal cystic lesions. However, the appearance of benign and malignant lesions may overlap, suggesting that distinct separation of these entities is not currently possible in all cases with MR imaging.

Fine-needle aspiration of cystic lesions of the kidney. Morphologic spectrum and diagnostic problems in 41 cases.

Although imaging studies show the nature of most cystic lesions of the kidney (RCs), many RCs require fine-needle aspiration (FNA) for accurate diagnosis. Interpretation of the FNAs remains challenging. The FNA specimens of 41 RCs were reviewed and correlated with imaging studies. Final diagnoses for 30 cytologically benign lesions were simple cyst (28), acquired cystic kidney (1), and cystic renal carcinoma (1). The fluid from the benign cysts displayed macrophages, epithelial cells from the cyst lining, tubular cells, neutrophils, and Liesegang rings. Fluid from the acquired cystic kidney and the cystic renal cell carcinoma showed features similar to those of the benign cysts. The 9 cases with "suspicious" cytology included 5 complex cystic lesions displaying rare but atypical epithelial cell clusters, 3 low-grade renal cell carcinomas with many mildly atypical papillary clusters of epithelial cells, and 1 simple benign cyst with many tubular cells. The 2 cytologically malignant lesions were cystic renal cell carcinomas with abundant tumor cells with partially clear cytoplasm and atypical nuclei admixed with abundant macrophages and lymphocytes; 1 case developed in a kidney with acquired cystic disease. Simple cysts remain the most frequently aspirated RCs, but complex cystic lesions are increasingly recognized. Since many RCs are composed of independent loculi, a nonrepresentative sample is a potential problem, and cytologic-radiologic correlation becomes mandatory. The "suspicious" patterns identified in this study should serve as diagnostic guidelines and set the foundation for future validation.

Sonographic features of benign papillary neoplasms of the breast: review of 22 patients

The sonographic features of 22 patients with histologically benign intraductal papillomas are presented, with clinical, mammographic, galactographic, and histopathologic correlation. The most common presenting feature in this series is a palpable central breast mass in an elderly woman. Sonography was abnormal in all 22 patients. The typical sonographic features include a well-defined, smooth-walled, solid, hypoechoic nodule or a lobulated, smooth-walled, cystic lesion with solid components. Dilated ducts are a common feature, often with visible solid intraluminal echoes. These findings suggest the diagnosis of an intraductal papilloma. The differential diagnosis includes fibroadenoma and phyllodes tumor (for large solid lesions) and intracystic carcinoma (for complex cystic lesions). Mammograms are frequently normal (36% of patients). When abnormal, the mammographic features are of a smooth-walled, well-defined mass or increased retroareolar opacity. Contrary to the reported literature, calcification was seen infrequently. We conclude that ultrasonography is useful in the detection and delineation of intraductal papillomas.

86 P - Usefulness of color doppler in assessing breast intracystic or intraductal solid lesions

The visualization of solid, echogenic content within a cystic lesion or a dilated duct poses the diagnostic problem of differentiating debris and clots versus a solid disorder. We used Color Doppler (CD) to asses vascular abnormalities within intracystic and intraductal lesions. Between January and November 1995 we encountered 48 complex cystic lesions and 9 dilated ducts with echogenic material. We used high frequency US probes (10 or 13 MHz) to assess the lesions and we also performed CD with low PRF (500Hz) to detect slow flow. All the patients underwent US guided aspiration biopsy of the complex cistic lesion with the tip of the needle carefully directed within the echogenic portion. In 39 cases the CD was negative as well as the cytological exam. Nine CD-positive cases were associated with 7 papillomas and 2 carcinomas and underwent surgery. Blood flow signal had been detected in 3 of the 4 cases with papilloma, while one was falsely negative. Two small cystic lesions (diameter less than 7mm) showed a clear CD signal, due to an artefactual intralesion projection of a nerby running vessel: the cytology was negative. We think that CD should always be performed in the assesment of intracystic and intraductal solid projections, but a better sensitivity to flow in small blood vessels is still needed.

The natural history of renal lesions in von Hippel-Lindau disease: a serial CT study in 28 patients.

Von Hippel-Lindau disease is a multisystem disorder predisposing to renal cysts and cancer. The growth and development of these renal lesions have not been documented previously. We reviewed serial CT scans to determine the rates and patterns of growth of renal lesions associated with von Hippel-Lindau disease. Twenty-eight patients with von Hippel-Lindau disease and renal involvement, including the spectrum from simple cysts to solid masses, had follow-up examinations for at least 1 year (mean, 2.4 years; range, 1-12 years) with serial contrast-enhanced abdominal CT. Renal lesions were measured and characterized. Surgical correlation was available in 12 patients. Two hundred twenty-eight lesions (eight lesions per patient) were detected. On the basis of their CT appearance, 168 lesions (74%) were classified as cysts, 18 (8%) as cysts with solid components, and 42 (18%) as solid masses. Among 12 patients with pathologic confirmation, the solid components of cystic lesions and solid lesions almost always contained renal carcinoma. The majority of cysts remained the same size (71%) or enlarged (20%); 9% became smaller or entirely involuted during the follow-up period. Although it is generally presumed that renal cysts are precursors to cancers, the transformation of a simple cyst to a solid lesion was observed in only two patients. Among the 42 solid lesions, all but two enlarged with time, with a mean doubling time of 10 months. The renal lesions associated with von Hippel-Lindau disease exhibited wide differences in growth. The majority of renal cysts grew slowly but some involuted. Transition to solid renal cancer was rare among cysts. Complex cystic and solid lesions contained neoplastic tissue that uniformly enlarged. These data may be used to help predict the progression of renal lesions in von Hippel-Lindau disease.