Alveolar capillary dysplasia: absence of CD117 immunoreactivity of putative hemangioblast precursor cells.

Alveolar capillary dysplasia is a rare cause of irreversible persistent pulmonary hypertension in newborns resulting from failure of formation of peripheral capillary loops with consequent reduction in the blood-gas barrier. The basic defect in morphogenesis is unknown, although it is postulated that there is a structural abnormality of the hemangioblast precursors of the primitive lung mesenchyme in the septal regions of the developing lung leading to abnormal vasculogenesis. Two cases of alveolar capillary dysplasia evaluated immunohistochemically showed uniform CD117 negativity in the septal interstitial cells forming the pulmonary capillaries.

Malignant adenomyoepithelial tumor of the breast: multi-immunolabeling technique and detailed immunophenotypic study.

Biphasic ductal and myoepithelial lesions of the breast are uncommon. A majority of these rare lesions behave in a benign fashion. Malignancy is rare, and preferentially involves the epithelial component.

Infantile lipofibromatosis of the upper limb.

The imaging features of extensive lipofibromatosis presenting in a 1-day-old female infant are reported. This lesion involved her entire right upper limb, extending from the axilla to the palm of the hand. Radiographs showed marked deformity and thinning of all the right upper-limb bones due to pressure effect of soft-tissue enlargement, especially affecting the distal humerus and proximal forearm bones.

Giant mixed-type perinephric liposarcoma.

Retroperitoneal fatty tumours are uncommon occurrences in current urologic practice, the differentials being lipomas, liposarcomas and extra-renal angiomyolipomas (AML). We report an unusual case of a 48-year-old Chinese female who presented with a 6.2 kg giant mixed-type liposarcoma in the left perinephric space, invading into the renal cortex and parenchyma.

Detection of atherosis in preeclamptic placentas: comparison of two gross sampling protocols.

Two standardized gross sampling protocols were compared with the intention of maximizing the histologic detection rate of atherosis in at-risk (i.e., preeclamptic) placentas.

Infantile myofibromatosis: a case report and review of the literature.

Infantile myofibromatosis is a rare mesenchymal disorder of infancy and childhood characterized by the formation of tumors in the soft tissues, muscle, bone, and viscera. Disease limited to the soft tissues, muscle, and bone has a good prognosis, and excision is curative; however, visceral involvement may be fatal. We present a case of infantile myofibromatosis in a 1-year-old boy and review the literature.

Intralobar sequestration of the lung is a congenital anomaly: anatomopathological analysis of four cases diagnosed in fetal life.

The origin of intralobar sequestration of the lung (ILS)-whether congenital or acquired--has often been controversial, since firm anatomical evidence of prenatal origin has been sparse. We describe four cases in which anomalous arterial supply from the aorta to abnormally echogenic lower lung lobes was demonstrated on routine antenatal ultrasound examination, and the diagnosis of ILS was subsequently confirmed by postmortem examination including bronchography of the fetuses at between 20 and 23 wk. One right-sided lesion was supplied from a branch of the coeliac axis, and three left-sided lesions were supplied from the thoracic aorta.

Rhabdoid tumor of the kidney is a component of the rhabdoid predisposition syndrome.

The rhabdoid predisposition syndrome (RPS) is characterized by pedigrees in which two or more individuals carry germline mutations of the hSNF5/INI1 tumor suppressor gene. The tumors associated with the syndrome include atypical teratoid/rhabdoid tumor (AT/RT), choroid plexus carcinoma, medulloblastoma, and extrarenal rhabdoid tumor. Rhabdoid tumor of the kidney (RTK) has not been described as part of the RPS.