Imaging and pathological comparison of inflammatory pseudotumor-like follicular dendritic cell sarcoma of the spleen: A case report and literature review.

Background: Inflammatory pseudotumor-like follicular dendritic cell sarcoma (IPT-like FDCS) is a rare subtype of follicular dendritic cell sarcoma (FDCS) that is mainly located in the liver and spleen (1). Splenic IPT-like FDCS is a rare low-grade malignancy with non-specific clinical manifestations and laboratory findings. Herein, we reported the pathological and imaging features of a case with splenic IPT-like FDCS. Case presentation: A 57-year-old woman was found to have a mass in the spleen during a physical examination and was hospitalized for further treatment. Her laboratory results were within the normal range. Unenhanced and contrast-enhanced computed tomography scans of the whole abdomen showed a round mass in the spleen, with a diameter of about 5 cm. After further examination with enhanced MRI, a provisional diagnosis of splenic hemangioma or splenic hamartoma was made. The patient underwent splenectomy, and the pathological diagnosis was splenic IPT-like FDCS. No tumor recurrence or metastasis was found during the 1-year follow-up after the operation. Conclusions: Herein, we reported a case of splenic IPT-like FDCS. Although the clinical examination and laboratory examination lack specificity, the imaging of this case showed that the lesion was a solid mass with progressive enhancement, and the central scar showed the characteristics of delayed enhancement, which facilitated the diagnosis.

Lipid-poor renal angiomyolipoma: Differentiation from clear cell renal cell carcinoma using wash-in and washout characteristics on contrast-enhanced computed tomography.

In the present study, a total of 82 patients (42 men and 40 women; age range, 24-84 years), including 34 patients with lipid-poor renal angiomyolipoma (AML) and 49 with clear cell renal cell carcinoma (RCC), who had undergone multiphase contrast-enhanced computed tomography (CT) (i.e., CT with unenhanced, corticomedullary, nephrographic and 5-min delay phase scanning) were evaluated. The peak enhancement attenuation value, net enhancement attenuation value, enhancement ratio, washout value and washout ratio were calculated to compare the enhancement characteristics between the two diseases. The results revealed that the lipid-poor AMLs had a significantly higher mean attenuation value compared with that of CCRCCs on unenhanced CT scans (37.8 vs. 30.9 HU; Mann-Whitney U test, P=0.003). In addition, significant differences were found between lipid-poor AMLs and CCRCCs with regard to wash-in (Mann-Whitney U test, P=0.001) and enhancement ratios (Mann-Whitney U test, P=0.010) on contrast-enhanced CT scans. A receiver operating characteristic (ROC) analysis revealed an area under the curve (AUC) of 0.722 using wash-in for differentiation between CCRCCs and lipid-poor AMLs. Lipid-poor AMLs exhibited a reduced washout of contrast enhancement (35.8±32.7 HU washout value; 29.4±0.187% washout ratio) compared with that of CCRCCs (48.3±28.4 HU washout value; 35.7±0.148% washout ratio; Mann-Whitney U test, P=0.037 and P=0.204, respectively). The ROC analysis result yielded an AUC of 0.639 for the use of washout to differentiate CCRCCs from lipid-poor AMLs. In summary, a larger wash-in and washout of contrast enhancement is a predictor that a lesion is CCRCC.

Acute thrombocytopenia: An uncommon complication occurring following transarterial chemoembolization in a patient with neuroendocrine hepatic metastases.

Neuroendocrine tumors are a group of carcinomas that secrete various polypeptides with hormonal activity. A significant percentage of patients already have hepatic metastases at the time of initial diagnosis, and 80-90% of these tumors are inoperable at the time of presentation. Transarterial chemoembolization (TACE) is the preferred approach for the management of neuroendocrine hepatic metastases. Although the technique is relatively safe, it is associated with several complications. The present study reported the case of a patient with neuroendocrine hepatic metastases who developed acute thrombocytopenia following TACE. To the best of our knowledge, acute thrombocytopenia occurring after TACE in a patient with neuroendocrine hepatic metastases has not been previously reported. In the present study, the hypothetical etiopathogenetic mechanisms were also discussed.