p57KIP2 immunostaining and molecular cytogenetics: combined approach aids in diagnosis of morphologically challenging cases with molar phenotype and in detecting androgenetic cell lines in mosaic/chimeric conceptions

Characteristics of hydatidiform moles: analysis of a prospective series with p57 immunohistochemistry and molecular genotyping

“…Thus, only one potential familial biparental hydatidiform mole was encountered in our study. The findings in our study also confirm that p57 immunohistochemical analysis is quite useful for recognition of androgenetic/biparental mosaic/ chimeric conceptions, 24 as discussed in detail in our recent study. 44 These include uniformly androgenetic/biparental mosaic specimens without molar features (probably early forms of placental mesenchymal dysplasia, which is characterized by androgenetic/biparental mosaicism and lack of trophoblastic hyperplasia), 62 androgenetic/ biparental mosaic specimens with a molar component (typically complete hydatidiform mole), and twin gestations comprised of complete hydatidiform mole and non-molar specimen components.…”

“…However, previous studies have demonstrated that diagnosis of hydatidiform moles based on morphology alone, even by experienced pathologists with specialized training, is subject to interobserver variability and therefore suboptimal diagnostic reproducibility. [9][10][11][12][13][14][15] A number of studies have demonstrated the value of ancillary techniques, including immunohistochemical analysis of cyclin-dependent kinase inhibitor 1C (CDKN1C/p57/Kip2, the protein product of the CDKN1C imprinted gene located at chromosome 11p15.5; referred to henceforth as p57) expression [16][17][18][19][20][21][22][23][24][25][26][27] and molecular genotyping via PCR amplification of short tandem repeat loci, 23,25,[28][29][30][31] for improving the diagnosis of hydatidiform moles. Genotyping is particularly valuable because it allows for specific distinction of complete hydatidiform moles, partial hydatidiform moles, and nonmolar specimens from one another due to their unique genetics.…”

Mosaics and moles

“…Indications of mosaicism/ chimerism with an androgenetic and a biparental cell population have been observed both in HMs, [12][13][14][15][16], present study in placentas displaying PMD, 18,[23][24][25] and in fetuses/children with malformations or growth abnormalities mimicking (part of) the Beckwith-Wiedemann phenotype. [25][26][27][28][29][30] The phenotype seems to correlate with the localization of the androgenetic cells.…”

“…[8][9][10][11] Another possible explanation is the coexistence of two diploid cell populations, one androgenetic and the other biparental. [12][13][14][15][16] In The Danish Mole Project, we have consecutively been collecting samples from HMs since 1986. In the present study, we have subjected 11 diploid HMs showing signs of having biparental genomes to detailed genetic analyses, and found indications that only a minority of these have 'true' biparental genomes, whereas most are mosaics.…”

The Utility of Immunohistochemistry in the Differential Diagnosis of Gynecologic Disorders

“…[100][101][102] This marker is expressed in the partial mole and nonmolar aborted placental tissue, and also in the intermediate trophoblast of the complete moles. [100][101][102] The use of p57 is particularly helpful in the early first trimester product of conception tissue, since the H&E morphologic features of complete molar gestation are not well developed. With rare exceptions (there always are) p57 staining will make this distinction (rarely, p57 can be expressed from a retained maternal segment of chromosome 10).…”