No abstract

Percutaneous aspiration of hydatid cysts of the liver was performed in 13 patients, and subsequent percutaneous drainage was performed in three of the 13. Aspiration was performed with ultrasound or computed tomographic guidance with 22-gauge to 19-gauge needles. Analysis of the aspirated specimen established the diagnosis of hydatid cysts in nine of the 13 patients. Fragments of the laminated membrane were seen in seven cases, scolices in two cases, and hooklets in two cases. In the four cases with negative results on aspiration, the diagnosis was established with surgical findings in one case and unequivocal immunologic results in three cases. In two patients, a mild allergic reaction with temporary pruritus was observed. In three patients, percutaneous drainage was performed with a 5-F to 8.3-F catheter, and sterilization of the cyst was achieved by injection of a scolicidal agent. No complications occurred at the time of drainage, and no recurrences developed during 6 months to 1 year after drainage.

The aim of this work was to study and compare the usefulness of dynamic contrast-enhanced spin-echo MR imaging with high temporal resolution hydroxymethylene diphosphonate technetium-99 m skeletal angioscintigraphy in predicting the osteosarcoma histological response to neoadjuvant chemotherapy. Twelve patients with resectable osteosarcoma were prospectively monitored with dynamic MR imaging and skeletal scintigraphy before start of neoadjuvant chemotherapy, after two cycles of therapy and before surgery. Neoplasm signal intensity and activity intensity were plotted against time, and slopes were calculated for percentage increase over baseline values in the first minute. Stability and increase in slope values during or after chemotherapy were defined as a "radiological non-response". Changes in slopes were compared with the "histological response" (Huvos grading). At midpoint of the chemotherapy, these two imaging modalities failed in predicting final histological response. After the completion of the chemotherapy, these imaging modalities allowed the prediction of histological response with the same accuracy (91 %). In this series, dynamic MR imaging and technetium skeletal scintigraphy provide similar results regarding the prediction of final histological response during neoadjuvant chemotherapy; these results cannot be used to modify the therapeutic protocol at midpoint of chemotherapy; these imaging tools predict accurately the histological response at the end of chemotherapy. These latter results may permit anticipation of the adjuvant chemotherapy strategy during decalcification procedures in resected osteosarcoma and thus to monitor chemotherapy in non-surgical osteosarcoma.

The fortuitous discovery of a left posterior cervico‐mediastinal mass during hospitalization for hemolytic anemia in an 18 month old baby is reported. Metaiodobenzylguanidine (MIBG) uptake suggested a sympathetic tissue origin of the mass despite negative catecholamines excretion, but histopathologic examination revealed a juvenile capillary angioma within a normal sympathic ganglion. Med. Pediatr. Oncol. 29:589–592, 1997. © 1997 Wiley‐Liss, Inc.