Evaluation of contrast-enhanced ultrasonography using perfluorobutane (Sonazoid(®)) in patients with small hepatocellular carcinoma: comparison with dynamic computed tomography.

This study aimed to elucidate the efficacy of contrast-enhanced ultrasonography (CEUS) with perfluorobutane (Sonazoid(®)) in the diagnosis of hepatocellular carcinomas (HCCs), particularly small HCCs, by comparing the results with dynamic computed tomography (Dy-CT). Seventy-nine nodules in 69 patients with chronic liver disease, suspected as HCCs were studied. The nodules were selected based on the results of B-mode ultrasonography and/or Dy-CT conducted between January and August 2007. The nodules were divided into two groups: the S-group with tumors ≤2 cm (49 nodules), and the L-group with tumors >2 cm (30 nodules). Typical HCCs were defined, and the nodules were enhanced and shown as defects in the arterial and late phase of Dy-CT, respectively. Target lesions were scanned using CEUS, and the results were compared with those of Dy-CT. The L-group nodules diagnosed as HCCs using Dy-CT were also diagnosed as HCCs using CEUS. In the S-group, the diagnostic sensitivity of CEUS was 94.7% and the specificity was 81.8%. We diagnosed two liver tumors that were detected by CEUS but not by Dy-CT; biopsies revealed one tumor to be a well-differentiated HCC and the other to be an atypical adenomatous hyperplasia. The sensitivity and specificity of CEUS against HCC were high even in the small-size HCCs. Thus, Sonazoid is useful in the screening for small HCCs.

Primitive neuroectodermal tumor of the pancreas.

The primitive neuroectodermal tumor (PNET) of the pancreas, a member of Ewing's sarcoma family of tumors, is extremely rare. We treated a 37-year-old Japanese man who had a solitary pancreatic tumor 40 mm in diameter and multiple hepatic tumors with surgical resection. The PNET was positive for CD99 on immunohistochemical staining. Fluorescence in situ hybridization (FISH) was also performed, which revealed a Ewing sarcoma breakpoint region 1 (EWSR1) 22q12 rearrangement. According to the Japan-Ewing protocol, chemotherapy with Ifomide (ifosfamide), etoposide, vincristine, and cyclophosphamide was given after surgery. To the best of our knowledge, to date 13 PNET cases have been reported with a mean age for all patients of 19.3 years old. Surgical resection was performed in most cases and some patients received postoperative chemotherapy. The clinicopathologic characteristics and management of this extremely rare disease are also discussed.