partial hydatidiform mole
Wednesday 10 April 2013
Partial Hydatidiform Mole by Ed Euthman
Definition: Hydatiform mole is a gestational trophoblastic disorder.
Cases of PARTIAL MOLE (PHM) are triploid and usually result from fertilization of an ovum by 2 sperms, although fertilization by a single diploid sperm cannot be excluded.
partial hydatiform mole
- With a partial mole, fetal tissue is often present. Fetal erythrocytes and vessels in the villi are a common finding.
- The chromosomal complement is 69,XXX or 69,XXY. This results from fertilization of a haploid ovum and duplication of the paternal haploid chromosomes or from dispermy.
- Tetraploidy may also be encountered. As in a complete mole, hyperplastic trophoblastic tissue and swelling of the chorionic villi occur.
p57KIP2 (CDKN1C) expression in molar pregnancy
- Negative p57KIP2 (CDKN1C) immunoreactivity (paternally imprinted, maternally expressed gene) is in perfect concordance with the androgenetic origin of molar pregnancies proven by DNA polymorphism. (15971478)
- p57KIP2 (CDKN1C) immunoreactivity, which can be performed in routine pathologic examinations, is a diagnostic tool to differentiate androgenetic complete moles from biparental conceptuses. (15971478)
- The p57KIP2 gene is paternally imprinted and is expressed from the maternal allele, and the lack of its protein product, as detected by IHC, has been documented in CHM (because CHMs lack maternal genomic DNA).
- In contrast, its mimics express p57KIP2, which serves as a surrogate marker for maternal DNA.
Distinction of hydatidiform moles (HMs) from nonmolar specimens (NMs) and subclassification of HMs as complete hydatidiform moles (CHMs) and partial hydatidiform moles (PHMs) are important for clinical practice and investigational studies.
Molecular genotyping can distinguish these entities by discerning androgenetic diploidy, diandric triploidy, and biparental diploidy to diagnose CHMs, PHMs, and NMs, respectively.
gestational trophoblastic diseases
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Diandric Triploid Hydatidiform Mole With Loss of Maternal Chromosome 11. Descipio C, Haley L, Beierl K, Pandit AP, Murphy KM, Ronnett BM. Am J Surg Pathol. 2011 Aug 29. PMID: 21881485
Popiolek DA, Yee H, Mittal K, Chiriboga L, Prinz MK, Caragine TA, Budimlija ZM. Multiplex short tandem repeat DNA analysis confirms the accuracy of p57(KIP2) immunostaining in the diagnosis of complete hydatidiform mole. Hum Pathol. 2006 Nov;37(11):1426-34. PMID: 16949913
Murdoch S, Djuric U, Mazhar B, Seoud M, Khan R, Kuick R, Bagga R, Kircheisen R, Ao A, Ratti B, Hanash S, Rouleau GA, Slim R. Mutations in NALP7 cause recurrent hydatidiform moles and reproductive wastage in humans. Nat Genet. 2006 Feb 5; PMID: 16462743
Romaguera RL, Rodriguez MM, Bruce JH, Zuluaga T, Viciana A, Penalver MA, Mehrdad N. Molar gestations and hydropic abortions differentiated by p57 immunostaining. Fetal Pediatr Pathol. 2004 Mar-Jun;23(2-3):181-90. PMID: 15768863
Jun SY, Ro JY, Kim KR. p57kip2 is useful in the classification and differential diagnosis of complete and partial hydatidiform moles. Histopathology. 2003 Jul;43(1):17-25. PMID: 12823708