Investigator

X Mona Guo

Assistant Professor Of Clinical Obstetrics and Gynecology · University of Southern California, Gynecology Oncology

XMGX Mona Guo
Papers(6)
Correspondence on “Se…Research on intrauter…OvaPrint—A Cell-free …Considerations for ro…A low-cost approach t…Associations between …
Collaborators(10)
Koji MatsuoBodour SalhiaDavid N. BuckleyGerald GoodenHeather MillerJuan Pablo LewingerLee P. ShulmanLynda RomanMonica NeumanMonique Spillman
Institutions(3)
University Of Souther…Northwestern Universi…University of Arkansa…

Papers

OvaPrint—A Cell-free DNA Methylation Liquid Biopsy for the Risk Assessment of High-grade Serous Ovarian Cancer

Abstract Purpose: High-grade serous ovarian carcinoma (HGSOC) is the most lethal epithelial ovarian cancer (EOC) and is often diagnosed at late stage. In women with a known pelvic mass, surgery followed by pathologic assessment is the most reliable way to diagnose EOC and there are still no effective screening tools in asymptomatic women. In the current study, we developed a cell-free DNA (cfDNA) methylation liquid biopsy for the risk assessment of early-stage HGSOC. Experimental Design: We performed reduced representation bisulfite sequencing to identify differentially methylated regions (DMR) between HGSOC and normal ovarian and fallopian tube tissue. Next, we performed hybridization probe capture for 1,677 DMRs and constructed a classifier (OvaPrint) on an independent set of cfDNA samples to discriminate HGSOC from benign masses. We also analyzed a series of non-HGSOC EOC, including low-grade and borderline samples to assess the generalizability of OvaPrint. A total of 372 samples (tissue n = 59, plasma n = 313) were analyzed in this study. Results: OvaPrint achieved a positive predictive value of 95% and a negative predictive value of 88% for discriminating HGSOC from benign masses, surpassing other commercial tests. OvaPrint was less sensitive for non-HGSOC EOC, albeit it may have potential utility for identifying low-grade and borderline tumors with higher malignant potential. Conclusions: OvaPrint is a highly sensitive and specific test that can be used for the risk assessment of HGSOC in symptomatic women. Prospective studies are warranted to validate OvaPrint for HGSOC and further develop it for non-HGSOC EOC histotypes in both symptomatic and asymptomatic women with adnexal masses.

A low-cost approach to salpingectomy at cesarean delivery

There is increasing adoption of opportunistic salpingectomy for ovarian cancer prevention at the time of gynecologic surgery, which includes the postpartum period. However, there is no consensus on an ideal surgical approach for the parturient vasculature. We describe a safe, low-cost, and accessible approach for bilateral salpingectomy during cesarean delivery that we call the "Mesosalpinx Isolation Salpingectomy Technique" (MIST) that can guide institutions to standardize their postpartum salpingectomy procedures when advanced vessel-sealing devices are not available. In the MIST technique, avascular windows are created within the mesosalpinx close to the tubal vessels. The vasculature is thus fully skeletonized and isolated from the adjacent mesosalpinx before suture ligation, which ensures security of the free-tie to the individual vessels and avoids sharp injury to the mesosalpinx. Not using vessel-sealing devices also eliminates the risk of thermal injury to the adjacent ovarian tissue and vasculature and potentially achieves a cost-savings for the hospital and patient. MIST has been performed in 141 cesarean deliveries in the past 4 years. There were no noted bleeding complications during the salpingectomy procedure, blood transfusions, or instances of postoperative surgical reexploration. In our experience, a surgeon who is new to the procedure takes approximately 15 minutes to complete a bilateral salpingectomy. Those surgeons who are experienced in MIST need only 5 minutes. A video is included that demonstrates the technique.

58Works
6Papers
12Collaborators

Positions

2023–

Assistant Professor Of Clinical Obstetrics and Gynecology

University of Southern California · Gynecology Oncology

Education

2023

Fellow

Keck School of Medicine of USC · Gynecologic Oncology

2016

MD

Yale University School of Medicine

2011

BS

Wellesley College

Links & IDs
0000-0002-5922-272X

Scopus: 57216500647