Hepatic mesenchymal hamartoma: cytogenetic analysis of a case and review of the literature.

Hepatic mesenchymal hamartoma (HMH) is a rare benign liver tumor generally occurring in young children. Abnormalities of chromosome 19q13.4 and chromosomal aneuploidy detected by flow cytometry have been reported in HMH. We recently analyzed a HMH in a 14-month-old girl and identified additional novel chromosome abnormalities, including hypodiploidy with deletions of several chromosomes, without rearrangement of 19q13.4 on both routine chromosome analysis and fluorescent in-situ hybridization analysis using subtelomere probes for chromosome 19q. This case underscores the need for chromosome analysis of all HMH and the need to report these changes to better understand the pathophysiology and the entire spectrum of cytogenetics of this uncommon tumor.

Noninvasive sacral chordoma presenting as a benign soft tissue mass.

In this case report, we describe a sacral chordoma, which had an atypical presentation as a mobile, encapsulated, benign soft tissue mass. The patient was asymptomatic, except for the slight enlargement of this lesion. Biopsy of this mass showed a lobulated tumor with bland neoplastic cells in a rich myxoid matrix with the classical immunohistochemical profile of chordoma. Opposite to this classical histological picture of chordoma, the imaging studies (computed tomography and magnetic resonance imaging) could not find any sacral involvement or lytic destruction. Surgical excision of this chordoma confirmed all preoperative findings and diagnoses, showing an encapsulated mass in the sacral soft tissue that has not invaded into the sacrum. This chordoma originated from the sacrococcygeal joint and grew parallel to the sacrum and below the skin. At the same time, histological sections and immunostains reconfirmed diagnosis of chordoma.