Imaging Utilization Patterns in the Follow-Up of Extremity Soft Tissue Sarcomas in the United States.

This study aimed to describe patterns of imaging utilization after resection of extremity soft tissue sarcoma in the United States, assess for potential disparities, and evaluate temporal trends. A retrospective cohort study using a national database of private payer claims data was performed to determine the utilization rate of extremity and chest imaging in a 5-year postoperative follow-up period for patients with extremity soft tissue sarcoma treated between 2007 and 2019. Imaging utilization was assessed according to patient demographics (age, sex, race and ethnicity, and region of residency), calendar year of surgery, and postoperative year. Associations of demographic variables with imaging use were assessed using chi-square tests, trends in imaging use were analyzed using the Cochran-Armitage trend test or linear regression, and associations of postoperative year with imaging use were evaluated with the Pearson Correlation coefficient. A total of 3707 patients were included. Most patients received at least 1 chest (74%) and extremity (53%) imaging examination during their follow-up period. The presence of surveillance imaging was significantly associated with age (P < 0.0001) and region (P = 0.0029). Over the study period, there was an increase in use of extremity MRI (P < 0.05) and ultrasound (P < 0.01) and chest CT (P < 0.0001) and a decrease in use of chest radiographs (P < 0.0001). Imaging use declined over postoperative years (decrease by 85%-92% from year 1-5). In conclusion, the use of surveillance imaging varied according to patient demographics and has increased for extremity MRI and ultrasound and chest CT over the study period.

Radiologist Characteristics Associated with Interpretive Performance of Screening Mammography: A National Mammography Database (NMD) Study.

Background Factors affecting radiologists' performance in screening mammography interpretation remain poorly understood. Purpose To identify radiologists characteristics that affect screening mammography interpretation performance. Materials and Methods This retrospective study included 1223 radiologists in the National Mammography Database (NMD) from 2008 to 2019 who could be linked to Centers for Medicare & Medicaid Services (CMS) datasets. NMD screening performance metrics were extracted. Acceptable ranges were defined as follows: recall rate (RR) between 5% and 12%; cancer detection rate (CDR) of at least 2.5 per 1000 screening examinations; positive predictive value of recall (PPV1) between 3% and 8%; positive predictive value of biopsies recommended (PPV2) between 20% and 40%; positive predictive value of biopsies performed (PPV3) between the 25th and 75th percentile of study sample; invasive CDR of at least the 25th percentile of the study sample; and percentage of ductal carcinoma in situ (DCIS) of at least the 25th percentile of the study sample. Radiologist characteristics extracted from CMS datasets included demographics, subspecialization, and clinical practice patterns. Multivariable stepwise logistic regression models were performed to identify characteristics independently associated with acceptable performance for the seven metrics. The most influential characteristics were defined as those independently associated with the majority of the metrics (at least four). Results Relative to radiologists practicing in the Northeast, those in the Midwest were more likely to achieve acceptable RR, PPV1, PPV2, and CDR (odds ratio [OR], 1.4-2.5); those practicing in the West were more likely to achieve acceptable RR, PPV2, and PPV3 (OR, 1.7-2.1) but less likely to achieve acceptable invasive CDR (OR, 0.6). Relative to general radiologists, breast imagers were more likely to achieve acceptable PPV1, invasive CDR, percentage DCIS, and CDR (OR, 1.4-4.4). Those performing diagnostic mammography were more likely to achieve acceptable PPV1, PPV2, PPV3, invasive CDR, and CDR (OR, 1.9-2.9). Those performing breast US were less likely to achieve acceptable PPV1, PPV2, percentage DCIS, and CDR (OR, 0.5-0.7). Conclusion The geographic location of the radiology practice, subspecialization in breast imaging, and performance of diagnostic mammography are associated with better screening mammography performance; performance of breast US is associated with lower performance. ©RSNA, 2021 Online supplemental material is available for this article.

Developmental hip dysplasia and hip ultrasound frequency in a large American payer database.

Developmental dysplasia of the hip (DDH) is an important contributor to musculoskeletal morbidity, but effective strategies to screen for DDH remain controversial. The current utilization of hip ultrasound (US) screening for DDH in the United States is not defined. This study utilized Optum's de-identified Clinformatics® Data Mart, a large commercial and Medicare Advantage claims database. The frequency of DDH and hip US utilization was estimated using billing data on an average of 2.9 million relevant beneficiaries included annually from 2007 through 2017. A total of 6806 DDH cases were identified with an average annual prevalence of 1.7 per 1000 infants, which was stable during the study period. Girls were more likely to be screened and diagnosed with DDH, comprising 72% of DDH cases with an OR of 2.55 (95% CI 2.42-2.69), p < 0.001. Hip US screening was employed in 0.9% of the infant population on average but increased substantially from 2007 (0.4%) to 2017 (2.2%). Most common billing diagnoses included hip deformity (27.4%), breech delivery (20.4%), and physical exam abnormality (17.7%). The average imaging costs per patient for all screened children was $108.94. Insurance claims reflect the current American practice of selective hip US with relative adherence to American Academy of Pediatrics guidelines based on reported diagnoses. While hip US utilization increased during the study period, prevalence of DDH diagnoses did not increase. Our results suggest that expansion of hip US screening may not effectively increase DDH detection although further investigation is needed to ascertain optimal screening strategies to improve patient outcomes.

Use and Cost of Actinic Keratosis Destruction in the Medicare Part B Fee-for-Service Population, 2007 to 2015.

Importance: Actinic keratosis is prevalent and has the potential to progress to keratinocyte carcinoma. Changes in the use and costs of actinic keratosis treatment are not well understood in the aging population. Objective: To evaluate trends in the use and costs of actinic keratosis destruction in Medicare patients. Design, Setting, and Participants: A billing claims analysis was performed of the Medicare Part B Physician/Supplier Procedure Summary Master Files and National Summary Data of premalignant skin lesion destructions performed from 2007 to 2015 among Medicare Part B fee-for-service beneficiaries. Main Outcomes and Measures: Mean number of actinic keratosis lesions destroyed and associated treatment payments in 2015 US dollars estimated per 1000 Medicare Part B fee-for-service beneficiaries. Data analysis was performed from November 2017 to July 2018. Results: More than 35.6 million actinic keratosis lesions were treated in 2015, increasing from 29.7 million in 2007. Treated actinic keratosis lesions per 1000 beneficiaries increased from 917 in 2007 to 1051 in 2015, while mean inflation-adjusted payments per 1000 patients decreased from $11 749 to $10 942 owing to reimbursement cuts. The proportion of actinic keratosis lesions treated by independently billing nurse practitioners and physician assistants increased from 4.0% in 2007 to 13.5% in 2015. Conclusions and Relevance: This study's findings suggest that actinic keratosis imposes continuously increasing levels of treatment burden in the Medicare fee-for-service population. Reimbursement decreases have been used to control rising costs of actinic keratosis treatment. Critical research may be warranted to optimize access to actinic keratosis treatment and value for prevention of keratinocyte carcinoma.

Evolving Use of Prebiopsy Prostate Magnetic Resonance Imaging in the Medicare Population.

PURPOSE: We assessed the changing use of prebiopsy prostate magnetic resonance imaging in Medicare beneficiaries. MATERIALS AND METHODS: Men who underwent prostate biopsy were identified in 5% Medicare RIFs (Research Identifiable Files) from October 2010 through September 2015. We evaluated the rate of prebiopsy prostate magnetic resonance imaging, defined as any pelvic MRI 6 months or less before biopsy with a prostate indication diagnosis code. Temporal changes were determined as well as variation by geography and among populations. RESULTS: In male Medicare beneficiaries the prebiopsy magnetic resonance imaging use rate increased from 0.1% in 2010 to 0.7% in 2011, to 1.2% in 2012, to 2.9% in 2013, to 4.7% in 2014 and to 10.3% in 2015. In 2015 the prebiopsy prostate magnetic resonance imaging rate varied significantly by patient age, including 5.7% for greater than 80 years vs 8.4% to 9.3% for other age ranges (p = 0.040) as well as by race, including 5.8% in African American vs 10.1% in Caucasian men (p = 0.009) and geographic region, including 6.3% in the Midwest to 12.5% in the Northeast (p <0.001). The rate was highest in Wyoming at 25.0%, New York at 23.7% and Minnesota at 20.5% but it was less than 1% in 10 states. CONCLUSIONS: Historical Medicare claims provide novel insights into the dramatically increasing adoption of magnetic resonance imaging prior to prostate biopsy. Following earlier minimal use the performance increased sharply beginning in 2013, exceeding 10% in 2015. However, substantial racial and geographic variation exists in adoption. Continued educational, research and policy efforts are warranted to optimize the role of prebiopsy magnetic resonance imaging and minimize sociodemographic and geographic disparities.

Changing Musculoskeletal Extremity Imaging Utilization From 1994 Through 2013: A Medicare Beneficiary Perspective.

OBJECTIVE: The objective of our study was to assess temporal changes in the utilization of musculoskeletal extremity imaging in Medicare beneficiaries over a recent 20-year period (1994-2013). MATERIALS AND METHODS: Medicare Physician Supplier Procedure Summary Master Files from 1994 through 2013 were used to study changing utilization and utilization rates of the four most common musculoskeletal imaging modalities: radiography, MRI, CT, and ultrasound. RESULTS: Utilization rates (per 1000 beneficiaries) for all four musculoskeletal extremity imaging modalities increased over time: 43% (from 441.7 to 633.6) for radiography, 615% (5.4-38.6) for MRI, 758% (1.2-10.3) for CT, and 500% (1.8-10.8) for ultrasound. Radiologists were the most common billing specialty group for all modalities throughout the 20-year period, maintaining dominant market shares for MRI and CT (84% and 96% in 2013). In recent years, the second most common billing group was orthopedic surgery for radiography, MRI, and CT and podiatry for ultrasound. The physician office was the most common site of service for radiography, MRI, and ultrasound, whereas the hospital outpatient and inpatient settings were the most common sites for CT. CONCLUSION: In the Medicare population, the most common musculoskeletal extremity imaging modalities increased substantially in utilization over the 2-decade period from 1994 through 2013. Throughout that time, radiology remained the most common billing specialty, and the physician office and hospital outpatient settings remained the most common sites of service. These insights may have implications for radiology practice leaders in making decisions regarding capital infrastructure, workforce, and training investments to ensure the provision of optimal imaging services for extremity musculoskeletal care.

Medicare Utilization of Vertebral Augmentation 2001 to 2014: Effects of Randomized Clinical Trials and Guidelines on Vertebroplasty and Kyphoplasty.

PURPOSE: Vertebral fractures have a substantial impact on the health and quality of life of elderly individuals as one of the most common complications of osteoporosis. Vertebral augmentation procedures including vertebroplasty and kyphoplasty have been supported as means of reducing pain and mitigating disability associated with these fractures. However, use of vertebroplasty is debated, with negative randomized controlled trials published in 2009 and divergent clinical guidelines. The effect of changing evidence and guidelines on different practitioners' utilization of both kyphoplasty and vertebroplasty in the years after these developments and publication of data supporting their use is poorly understood. METHODS: Using national aggregate Medicare claims data from 2002 through 2014, vertebroplasty and kyphoplasty procedures were identified by provider type. Changes in utilization by procedure type and provider were studied. RESULTS: Total vertebroplasty billing increased 101.6% from 2001 (18,911) through 2008 (38,123). Total kyphoplasty billing frequency increased 17.2% from 2006 (54,329) through 2008 (63,684). Vertebroplasty billing decreased 60.9% from 2008 through 2014 to its lowest value (14,898). Kyphoplasty billing decreased 8.4% from 2008 (63,684) through 2010 (58,346), but then increased 7.6% from 2010 to 2013 (62,804). CONCLUSIONS: Vertebroplasty billing decreased substantially beginning in 2009 and continued to decrease through 2014 despite publication of more favorable studies in 2010 to 2012, suggesting studies published in 2009 and AAOS guidelines in 2010 may have had a persistent negative effect. Kyphoplasty did not decrease as substantially and increased in more recent years, suggesting a clinical practice response to favorable studies published during this period.

The Expanding Role of Advanced Practice Providers in Urologic Procedural Care.

OBJECTIVE: To understand the role of Advanced Practice Providers (APPs) in urologic procedural care and its change over time. As the population ages and the urologic workforce struggles to meet patient access demands, the role of APPs in the provision of all aspects of urologic care is increasing. However, little is currently known about their role in procedural care. MATERIALS AND METHODS: Commonly performed urologic procedures were linked to Current Procedural Terminology (CPT) codes from 1994 to 2012. National Medicare Part B beneficiary claims frequency was identified using Physician Supplier Procedure Summary Master Files. Trends were studied for APPs, urologists, and all other providers nationally across numerous procedures spanning complexity, acuity, and technical skill set requirements. RESULTS: Between 1994 and 2012, annual Medicare claims for urologic procedures by APPs increased dramatically. Cystoscopy increased from 24 to 1820 (+7483%), transrectal prostate biopsy from 17 to 834 (+4806%), complex Foley catheter placement from 471 to 2929 (+522%), urodynamics testing from 41 to 9358 (+22,727%), and renal ultrasound from 18 to 4500 (+24,900%) CONCLUSION: We found dramatic growth in the provision of urologic procedural care by APPs over the past 2 decades. These data reinforce the known expansion of the APP role in urology and support the timeliness of ongoing collaborative multidisciplinary educational efforts to address unmet needs in education, training, and guideline formation to maximize access to urologic procedural services.

Changing Medicare Utilization of Minimally Invasive Procedures for the Treatment of Chronic Venous Insufficiency.

PURPOSE: To examine changes in the utilization of procedures related to treatment of chronic venous insufficiency (CVI) in the Medicare population. MATERIALS AND METHODS: Service-specific claims data for phlebectomy, sclerotherapy, and radiofrequency (RF) and laser ablation were identified by using Medicare Physician Supplier Procedure Summary master files from 2005 through 2014. Longitudinal national utilization rates were calculated by using annual Medicare enrollment data from 2005 through 2013. Procedure volumes by specialty group and site of service were analyzed. RESULTS: Total annual claims for these procedures in the Medicare fee-for-service beneficiaries increased from 95,206 to 332,244 (Compound Annual Growth Rate [CAGR], 15%) between 2005 and 2014. Per 1,000 beneficiaries, overall utilization increased annually from 2.8 in 2005 to 9.4 in 2013. Most procedures were performed in the private office setting (92% in 2014). In 2014, radiologists had a 10% relative market share, compared with vascular surgeons, other surgeons, and cardiologists, who had 26%, 25%, and 14% market shares, respectively. Cardiologists had the fastest relative growth, with a CAGR of 51% compared with 23% for radiology, 12% for vascular surgery, and 13% for other surgery. Total venous RF ablation services grew with a CAGR of 31%, with radiology and cardiology growing most rapidly (40% and 79%, respectively). Total venous laser ablation services grew with a CAGR of 22%, with radiology growing 15% and cardiology growing most rapidly at 44%. CONCLUSIONS: Utilization of CVI procedures in the Medicare population increased markedly from 2005 through 2014. The overwhelming majority are performed in the private office setting by nonradiologists.

Enteral Access Procedures: An 18-Year Analysis of Changing Patterns of Utilization in the Medicare Population.

PURPOSE: To evaluate national trends in enteral access and maintenance procedures for Medicare beneficiaries with regard to utilization rates, specialty group roles, and sites of service. MATERIALS AND METHODS: Using Medicare Physician Supplier Procedure Summary Master Files for the period 1994-2012, claims for gastrostomy and gastrojejunostomy access and maintenance procedures were identified. Longitudinal utilization rates were calculated using annual enrollment data. Procedure volumes by site of service and medical specialty were analyzed. RESULTS: Between 1994 and 2012, de novo enteral access procedure utilization decreased from 61.6 to 42.3 per 10,000 Medicare Part B beneficiaries (-31%). Gastroenterologists and surgeons performed > 80% of procedures (unchanged over study period) with 97% in the hospital setting. Over time, relative use of an endoscopic approach (62% in 1994; 82% in 2012) increased as percutaneous (21% to 12%) and open surgical (17% to 5%) procedures declined. Existing enteral access maintenance services increased 29% (from 20.1 to 25.9 per 10,000 beneficiaries). Radiologists (from 13% to 31%) surpassed gastroenterologists (from 36% to 21%) as dominant providers of maintenance procedures. Emergency physicians (from 8% to 23%) and nonphysician providers (from 0% to 6%) have seen rapid growth as maintenance services providers as these services have transitioned increasingly to the emergency department setting (from 18% to 32%). CONCLUSIONS: Among Medicare beneficiaries, de novo enteral access procedures have declined in the last 2 decades as existing access maintenance services have increased. The latter are increasingly performed by radiologists, emergency physicians, and nonphysician providers.

Medicare Utilization of CT Angiography from 2001 through 2014: Continued Growth by Radiologists.

PURPOSE: To examine changes in utilization of computed tomography (CT) angiography nationally and changing relative specialty roles in examination interpretation. MATERIALS AND METHODS: Service-specific claims data for region-specific CT angiography examinations were identified using Medicare Physician Supplier Procedure Summary Master Files from 2001 through 2014. Longitudinal national utilization rates were calculated using annual Medicare enrollment data for 2001-2013. Procedure volumes by specialty group and site of service were analyzed. RESULTS: Total annual claims for CT angiography for Medicare fee for service beneficiaries increased from 64,846 to 1,709,088 (compound annual growth rate [CAGR] 29%) between 2001 and 2014. Per 1,000 beneficiaries, overall CT angiography utilization increased annually from 2.1 in 2001 to 47.6 in 2013. Overall interpretation market share increased 4% (91%-95%) for radiology. Cardiology increased from 1% in 2001 to 6% in 2007 but decreased annually to 2% in 2014. Vascular surgery market share remained < 1% throughout the study period. Growth of CT angiography in the emergency department (ED) outpaced all other sites of service, increasing from 11% to 28% (CAGR 38%). The chest was the dominant body region imaged with CT angiography, increasing from 36,984 to 914,086 (CAGR 28%). CONCLUSIONS: Utilization of CT angiography in the Medicare population increased markedly for 2001-2014, particularly in the ED, with radiologists remaining dominant providers. The chest is the most common body region imaged with CT angiography.

Reassessing medicare trends in diagnostic CT colonography after achieving CPT code category I status.

PURPOSE: Compare national trends in utilization and coverage of diagnostic (non-screening) computed tomography colonography (CTC) in the Medicare population before and after achieving Current Procedural Terminology(®) (CPT) Category I code status in 2010. METHODS: Claims by provider type and location for diagnostic CTC were identified between 2005 and 2013 using Medicare Physician Supplier Procedure Summary Master Files. Frequencies of billed and denied services were used to calculate denial rates for CTC and abdominal computed tomography (CT). PubMed search for articles with "CT colonography" in abstract or title during 1997-2013 was performed. Publications were recorded yearly and matched to CTC denial rates. RESULTS: Annual Medicare claims for diagnostic CTC increased 212% during 2005-2009 in Category III status and increased 27.4% during 2009-2013 after implementation of Category I codes. Claims for abdominal CT rose 13.4% over the same overall period. Denial rates decreased from 70% to 32.8% between 2005 and 2009, and fluctuated between 24.7 and 30.6% thereafter. Denial rates for abdominal CT remained constant (4.1%-4.6%). From 2005 to 2013, services grew most in the private office (1678-7293) and hospital outpatient (1644-6449) settings with radiologists performing 93.3% of CTC. 1037 CTC publications were identified which increased 3567% between 1997 (3) and 2008 (107), plateaued until 2010 (114) and declined thereafter (75 in 2013). CONCLUSIONS: Diagnostic CTC grew dramatically from 2005 to 2009, but slowed thereafter; even after achieving CPT Category I code status in 2010. Medicare denial rates declined during early years but later stabilized which paralleled a slowing in new peer-reviewed research. CTC continues to be performed predominately by radiologists in the outpatient setting.

Medicare Utilization of Vascular Ultrasound From 1998 to 2013: Continued Growth in Both Radiologist and Nonradiologist Imaging.

PURPOSE: The aim of this study was to assess national trends in the utilization of vascular ultrasound (VUS) and changing relative specialty roles in examination interpretation. METHODS: Service-specific claims data for VUS studies were identified using Medicare Physician Supplier Procedure Summary Master Files for the period from 1998 to 2013. Longitudinal national utilization rates were calculated using annual Medicare enrollment data for 1998 to 2012. Procedure volumes by specialty group and site of service were analyzed. RESULTS: Total annual claims for VUS studies for Medicare fee-for-service beneficiaries increased from 4,422,360 to 8,599,677 (+94.5%) between 1998 and 2013. Per 1,000 beneficiaries, overall utilization rose from 145.93 in 1998 to 264.26 in 2012 (+81.1%). However, this peaked in 2009 at 270.43 and has been slowly declining each year since. Overall market share decreased from 43% to 41% for radiology and increased from 10% to 16% and from 9% to 17% for vascular surgery and cardiology, respectively. Compound adjusted growth rate increases were 4.2% for radiology, 7.8% for vascular surgery, and 8.7% for cardiology. CONCLUSIONS: Utilization of VUS in the Medicare population increased from 1998 through 2009 but has been declining ever since. Although radiology has maintained the dominant market share over time, relative growth by cardiology and vascular surgery has outpaced that by radiology.

Expanding roles of nurse practitioners and physician assistants as providers of nonvascular invasive radiology procedures.

PURPOSE: To evaluate national trends in nonvascular invasive radiology procedures performed by advanced practice providers (APPs), focusing specifically on nurse practitioners and physician assistants. METHODS: Nonvascular invasive radiology procedures commonly performed by APPs at our 2 largest hospitals were used to identify procedure groups for national trends analysis. We mapped categories of services annually to then-current Current Procedural Terminology codes from 1994 to 2012 and identified national Medicare Part B beneficiary paid claims frequency using Physician Supplier Procedure Summary Master Files. Trends were studied for APPs, radiologists, and all providers nationally for 7 categories of service: paracentesis, thoracentesis, fine-needle aspiration (FNA), superficial lymph node biopsy, abdominal biopsy, thoracic biopsy, and abdominal drainage. RESULTS: Of 1,352 nonvascular invasive procedures performed by APPs at our facilities over a 1-year period through August 2013, a total of 1,161 (85.9%) fell into the 7 defined categories. Between 1994 and 2012, national Medicare claims by APPs increased dramatically for all of these categories: paracentesis from 0 to 17,967; thoracentesis from 119 to 4,141 (+3,379%); FNA from 0 to 3,921; superficial lymph node biopsy from 0 to 251; abdominal biopsy from 1 to 1,819 (+1,818%); thoracic biopsy from 0 to 552; and abdominal drainage from 37 to 410 (+1,008%). Overall, volumes increased for both radiologists and all providers, with the total fraction of national services performed by APPs increasing from 0% to 10.7% for paracentesis, 0.1% to 5.7% for thoracentesis, 0% to 2.1% for FNA, 0% to 1.4% for superficial lymph node biopsy, 0% to 1.7% for abdominal biopsy, 0% to 1.0% for thoracic biopsy, and 0.1% to 1.2% for abdominal drainage. CONCLUSIONS: Although APPs perform a relatively small portion of commonly performed nonvascular invasive radiology procedures nationally, paid Medicare claims for those services have increased dramatically over nearly 2 decades, and at a faster pace than that for all providers as a whole. Given the multiple hurdles involved in obtaining Medicare reimbursement, that growth indicates increasing acceptance of APPs as procedure service providers at the institutional credentialing, state licensure, and payer policy levels.

Decidual cell polyploidization necessitates mitochondrial activity.

Cellular polyploidy has been widely reported in nature, yet its developmental mechanism and function remain poorly understood. In the present study, to better define the aspects of decidual cell polyploidy, we isolated pure polyploid and non-polyploid decidual cell populations from the in vivo decidual bed. Three independent RNA pools prepared for each population were then subjected to the Affymetrix gene chip analysis for the whole mouse genome transcripts. Our data revealed up-regulation of 1015 genes and down-regulation of 1207 genes in the polyploid populations, as compared to the non-polyploid group. Comparative RT-PCR and in situ hybridization results indeed confirmed differential expressional regulation of several genes between the two populations. Based on functional enrichment analyses, up-regulated polyploidy genes appeared to implicate several functions, which primarily include cell/nuclear division, ATP binding, metabolic process, and mitochondrial activity, whereas that of down-regulated genes primarily included apoptosis and immune processes. Further analyses of genes that are related to mitochondria and bi-nucleation showed differential and regional expression within the decidual bed, consistent with the pattern of polyploidy. Consistently, studies revealed a marked induction of mitochondrial mass and ATP production in polyploid cells. The inhibition of mitochondrial activity by various pharmacological inhibitors, as well as by gene-specific targeting using siRNA-mediated technology showed a dramatic attenuation of polyploidy and bi-nucleation development during in vitro stromal cell decidualization, suggesting mitochondria play a major role in positive regulation of decidual cell polyploidization. Collectively, analyses of unique polyploidy markers and molecular signaling networks may be useful to further characterize functional aspects of decidual cell polyploidy at the site of implantation.