Ordering Recommendation

Distinguish between partial hydatiform mole (PHM) and complete hydatiform mole (CHM).

New York DOH Approval Status

This test is not New York state approved. There are no New York state-approved laboratories available. Submit a Non-Permitted Laboratory Request Form (NPL) to the NYDOH prior to collection of specimen. If NPL is approved by NYDOH, and sample is received at ARUP, testing will be performed.

Specimen Required

Patient Preparation
Collect

Products of conception in paraffin tissue block.

Specimen Preparation

Formalin fix and paraffin embed products of conception in a tissue block. Tissue transport kit (ARUP Supply #47808) recommended, available online through eSupply using ARUP Connect™ or contact ARUP Client Services at 800-522-2787.

Storage/Transport Temperature

Refrigerated

Unacceptable Conditions
Remarks

Include H&E-stained slide if only submitting tissue shavings (no block submitted). Also include a copy of the surgical pathology report, if available.
If multiple specimens (blocks or slides) are sent to ARUP, they must be accompanied by one of the following: an order comment indicating that the ARUP pathologist should choose the specimen most appropriate for testing (e.g., "Choose best block"), or individual orders for each sample submitted. A Pathologist Block Selection Fee (ARUP test code 3002076) will be added to orders that utilize the first option. If multiple specimens are sent to ARUP without a request for pathologist block/slide selection or individual orders, they will be held until clarification is provided.

Stability

Ambient: Indefinitely; Refrigerated: Indefinitely; Frozen: Unacceptable

Methodology

Quantitative Flow Cytometry

Performed

Tue, Thu

Reported

3-9 days

Reference Interval

Interpretive Data

Diagnostic Data: Flow cytometry can be used to help identify partial hydatidiform moles. Partial moles are usually triploid while complete moles are diploid, tetraploid, or aneuploid [Clinical Medicine: Pathology, 2008;1:61-67; Gynecol Oncol, 2001;81:67-70]. However, most products of conception are diploid, so a diploid histogram does not suggest a complete mole unless supported clinically and microscopically.

Prognostic Data: Persistent trophoblastic disease occurs in about 20% of diploid and tetraploid complete moles. Aneuploid complete moles may be associated with less risk for persistent disease [Gynecol Oncol, 2001;81:67-70]. The risk of persistent trophoblastic disease after a triploid mole is very low (0 out of 105 cases) [Obstet Gynecol, 2006;107:1006-1011]. In rare cases, a triploid result can also be due to nonmolar triploidy (digynic triploidy) where the extra haploid set of chromosomes are maternal. Nonmolar digynic triploid pregnancies are not associated with gestational trophoblastic disease and do not lead to an increased risk of recurrent molar pregnancy. Differentiating between a triploid partial mole and nonmolar triploid pregnancy requires clinical, microscopic, and molecular genetic testing correlation. [Clin Case Rep. 2020;8(5):785-789].

Compliance Category

Laboratory Developed Test (LDT)

Note

A thin section of each tissue submitted is stained with H&E. The DNA content is classified as diploid, triploid, tetraploid, or aneuploid. The DNA index is the ratio of the DNA content of abnormal cells compared to normal cells.

Hotline History

N/A

CPT Codes

88182

Components

Component Test Code* Component Chart Name LOINC
0095737 Source: 31208-2
2006308 POC - DNA Analysis 30911-2
2008898 POC - DNA Index 30912-0
2010872 EER DNA, POC 11526-1
* Component test codes cannot be used to order tests. The information provided here is not sufficient for interface builds; for a complete test mix, please click the sidebar link to access the Interface Map.

Aliases

  • DNA Ploidy for Hydatidiform Moles
  • Partial and Complete Hydatidiform Moles
  • Partial or Complete Hydatidiform Moles
  • Products of Conception
Products of Conception, Ploidy by Flow Cytometry