The aim of this study was to evaluate the clinical efficacy and safety of the ultrasoundguided fine needle biopsy (UG-FNB) of the spleen in a large population of patients. We collected retrospectively the findings concerning the application of UG-FNB of the spleen from eight Italian clinical centers that utilized this technique for at least ten years. A data schedule was sent to all centers to collect information about techniques, results, and complications of UG-FNB of the spleen. We analyzed 398 biopsy procedures both on focal lesions (257 cases) and on splenic parenchyma (141 cases). The overall accuracy was 90.9% for the series as a whole, 84.9% for cytological sampling, 88.3% for microhistological sampling, and 90.3% for both cytological and histological sampling (double biopsy). Tissue core biopsy yielded better overall accuracy in patients with suspected splenic involvement by lymphoma (90.9% vs. 68.5% for cytology). The complication rate was low (no death cases, less than 1% for major complications, and 5.2% for all complications). No predictive factors were able to detect high-risk situations. The operator's skill (higher number of performed procedures) was significantly related to better overall accuracy. Conversely, the complication rate was not affected. UG-FNB of the spleen is a very effective diagnostic procedure with low risk for the patient. Aspiration cytology and core needle biopsy showed similar diagnostic yields, except for the diagnosis of splenic lymphoma, in which core needle biopsy obtained better results. Am. J. Hematol. 67:93-99, 2001.

Some procedural aspects of PEI treatment differ among the various centers a standardization is advisable. In the present survey PEI is a low-risk technique.

This preliminary clinical experience seems to confirm the possibility of using SonoVue enhanced US to make a differential diagnosis between infectious and neoplastic lesions based on a qualitative and quantitative assessment, by evaluating the enhancement pattern (homogeneous or inhomogeneous), arrival time of the contrast agent in the lesion, the possibility to identify the pulmonary arteries and time of contrast agent elimination.

An analysis of the epidemiology of non-parasitic hepatic cysts (NPHCs) has been carried out comparing these data with those of the current literature. This sample shows an incidence of 4.65%, which is greater than those reported by other authors. No difference between the two sexes was seen, but a very high incidence above 40 years of age was found.

Ultrasound (US) imaging of the spleen was considered of little use in the past and was performed only to distinguish between cystic and solid lesions. However, in the last decade due to experience acquired and the introduction of second-generation contrast agents, this technique has been re-evaluated as contrast-enhanced US (CEUS) allows detection and characterization of most focal lesions of the spleen with a high sensitivity and a good specificity. Gray-scale US presents a low specificity in splenic infarctions with a high rate of false negative cases, whereas specificity reaches 100 %, if the examination is performed using US contrast agents. Gray-scale US can provide a correct diagnosis in simple cysts, whereas CEUS is useful when cystic lymphangioma is suspected. In the study of splenic lesions, the most important problem is to differentiate between angioma, hamartoma, lymphoma, and metastasis. CEUS reaches a good specificity in the differentiation of benign from malignant splenic lesions, as hypo-enhancement in the parenchymal phase is predictive of malignancy in 87 % of cases. In conclusion, Gray-scale US and particularly CEUS are at present widely indicated in the study of focal splenic lesions.Keywords Focal splenic lesion Á Splenic angioma/ hamartoma Á Splenic cysts Riassunto L'ecografia splenica è stata considerata nel passato poco utile ed indicata solo nella diagnosi differenziale tra lesioni cistiche e solide. Nell'ultimo decennio grazie alla maggior esperienza ed all'utilizzo dei mezzi di contrasto ecografici di II generazione (CEUS), questa metodica è stata rivalutata, in quanto consente di evidenziare e caratterizzare con elevata sensibilità e buona specificità la maggior parte delle lesioni focali della milza. Negli infarti splenici l'ecografia B-Mode ha una bassa specificità con elevata percentuale di falsi negativi, mentre questa risulta il 100 %, quanto l'esame è eseguito con i mezzi di contrasto ecografici. Nelle cisti semplici l'esame ecografico è sufficiente per porre una corretta diagnosi, mentre la CEUS può risultare utile nel sospetto di linfoangioma cistico. Il problema più importante a livello splenico è quello di definire con la maggior accuratezza possibile la diagnosi differenziale tra Angioma/Amartoma e Linfoma/Metastasi. La CEUS presenta nella lesioni spleniche una buona specificità nel differenziare una lesione benigna da una maligna, in quanto la presenza di ipoehnancement in fase parenchimale è predittiva nell'87 % dei casi di malignità. In conclusione l'ecografia B-Mode ed ancor più la CEUS trova al momento attuale ampie indicazioni nelle lesioni focali spleniche.