AIM:To compare the expression of p57 as indirect marker of genomic imprinting of CDKN1C in a series of infantile hemangiomas (IH) of patients with and without Beckwith-Wiedemann syndrome.MATERIALS AND METHODS:Cases of mammary, salivary gland, liver (one each), and placental (2 cases) capillary hemangiomas all with histological features akin to IH as well as typical examples of cutaneous (8 cases) IH were analyzed by immunohistochemistry with antibody against p57(KIP2). This protein is the product of CDKN1C an imprinted, maternally expressed gene. The liver hemangioma and both chorioangiomas were from patients with Beckwith-Wiedemann syndrome. Positive and negative controls included normal placental tissue and complete hydatidiform mole, respectively. Positive staining was localized to nuclei.RESULTS:Endothelial cells from the skin, breast and salivary gland hemangiomas were p57(KIP2) positive while chorioangiomas and liver IH presenting in patients with Beckwith-Wiedemann syndrome were negative. Controls reacted appropriately.CONCLUSIONS:Endothelial cells of IH not associated with BWS normally express p57(KIP2) while chorioangiomas and IH of the liver associated with BWS do not. These results suggest that the BWS IH may result from dysregulation of the cell cycle.

Testicular microlithiasis (TM) is being recognized with increasing frequency because of the extensive use of ultrasound. TM has been linked to several pathological conditions of the testis, mainly with an increased risk for developing germ cell tumors. The pathogenesis of the microcalcospherites is unknown. We report a detailed morphologic and immunohistochemical analysis of 11 patients (age: 3 to 15 years) with TM. The microliths were related neither to the age of the children nor to the developmental stage of the testis. The microcalcospherites were PAS positive or collagen IV positive or surrounded by a collagen IV–positive band, extratubular structures consistently associated with double-layered annular tubules. Immature, smaller Sertoli cells commonly lined the inner layer of the annular tubules. Some microcalcospherites showed an interposed thin band of connective tissue cells between the concretion and the tubular basement membrane. The annular tubules seemed to result from progressive wrapping of the growing tubules around the concretions. Our findings favor the interpretation that the microliths are located outside the tubules and have been present there since very early stages of testicular development. The association of the calcospherites with Sertoli cells and annular tubules formation, like that of gonadal stromal tumor with annular tubules of the ovary and large cell–calcifying Sertoli cell tumor of the testis, favors the hypothesis that microliths may result from multifocal Sertoli cell dysfunction. Since both tumors are related to the Peutz-Jeghers syndrome, it is proposed that TM may result from the same genetic abnormalities. It is unclear how this may be related to the development of germ cell tumors. However, the presence of calcospherites in gonadoblastoma may indicate a combined Sertoli cell and germ cell derangement in the genesis of TM.

Adequate interpretation of clinical and histopathologic features of giant congenital melanocytic nevus (GCMN) in newborns is a continued challenge. A GCMN with three large nodules and three polypoid exophytic tumors presented in the dorsum of a female full-term newborn, the borders exhibiting a spotted grouped pattern. Microscopic examination revealed a peculiar adnexal-centered (eccrine sweat gland ducts, acrosiringia, and hair infundibula) compound nevus expressing pagetoid intraepidermal spreading of epithelioid melanocytes. The nodules represented an extensive ganglioneuromatous component. The neurons and their neuropil were positive for neuron-specific enolase, S-100, synaptophysin, tyrosine hydroxilase, and PGP 9.5. In addition to these components, a poorly differentiated, fusiform, low-mitotic rate population of cells undergoing epithelioid differentiation (and probably neuronal differentiation) with nodular arrangement was also present in the polypoid tumors and deeper parts of the nevus, in part intermixed with the neurons. These cells were vimentin positive but S-100 negative. FISH studies revealed these cells to express three signals for the centromeric probe for chromosome 7 whereas the neuronal component showed just two. Adnexal-centered arrangement of melanocytes has not been emphasized in GCMN. Ganglioneuromatous differentiation has been rarely reported in this condition. Trisomy 7 in GCMN has been reported only once previously.

The present report describes an example of multifocal (two) yolk sac tumor (YST) with mesenchyme-like and enteroid patterns found in the placenta (730 g) of a newborn (4200 g) with Wiedemann-Beckwith syndrome (WBS) phenotype (macroglossia, omphalocele, hemihypertrophy, cardiomegaly, hypoglycemia). YST has not been previously reported to develop in the placenta. This case expands further the spectrum of alterations found in the placenta in the WBS and fits in the list of tumors related to WBS.

Massive myocardial calcification (MMC) in the perinatal period is an unusual finding considered to be a unique tissue reaction. This report summarizes the clinical and pathologic findings of seven cases of perinatal MMC. All patients presented clinical evidence of myocardial damage. In two cases arrhythmia was detected in utero. Four cases presented with hydrops, one of which was associated with major heart malformation. One case was a trisomy 13. Three cases had polyhydramnios. Our results demonstrate that calcification follows progressive stages from patches of calcified myocardial cells (stage I), to coagulative and colliquative myocytolysis with clusters of interstitial mononucleated cells (stage II), to collapsing fibrosis with granulation tissue and multinucleated regenerative myocardial cells (stage III), and finally to fibrous scars containing entrapped remaining myocardial cells (stage IV). Literature review and our findings suggest that perinatal MMC results from different conditions inducing hypoxic-ischemic damage that later is followed by progressive scarring if the patient survives the acute stage. The lesion may represent the human counterpart of the so-called dystrophic cardiac calcinosis in mice. This disease is related to an abnormality at the Dyscalc locus of proximal chromosome 7 (syntenic with human chromosome 19q13 and 11p15).

The Di George syndrome is an anomaly characterized by the complete or partial absence of derivatives of the third and fourth pharyngeal pouches often associated with defective development of the third, fourth, and sixth aortic arches leading to absence or hypoplasia of the thymus and parathyroid glands and to cardiovascular anomalies. The fifth pharyngeal pouch, often considered a part of the fourth pouch, gives rise to the ultimobranchial body (UB), which becomes incorporated into the thyroid gland and is thought to be the source of thyroid C cells. Robinson suggested that complete or partial absence of the UB should be considered a part of the Di George anomaly. To substantiate this theory, the thyroid glands of 11 patients with the Di George syndrome and 11 age-matched control infants were examined immunohistochemically using the immunoperoxidase technique for presence or absence of thyrocalcitonin (TC)-containing cells. Only three of 11 patients with the Di George syndrome had TC-containing cells in their thyroid glands (27 per cent), and nine of 11 control infants had these cells (82 per cent). It is concluded that thyroid C cell deficiency is present in most patients with Di George anomaly, suggesting a relationship between these cells and development of derivatives of the third through fifth visceral pouches. Furthermore, there is a spectrum of deficiency of thyroid C cells in these individuals comparable with the spectrum of partial to complete absence of third and fourth pharyngeal pouch derivatives regarding thymus and parathyroid glands. Immunostaining for TC of the lungs of all infants with the Di George syndrome and control infants revealed similar numbers of thyrocalcitonin-containing cells in both groups. Asynchronous development of thyroid and lung thyrocalcitonin-containing cells in those with the Di George syndrome favors the theory that the latter develop independently of derivatives of the third through fifth visceral pouches. This study further supports a neural crest origin of the Di George anomaly and strengthens the concept that the Di George anomaly is a neurocristopathy.