16: The Incidence of Adjacent Synchronous Ipsilateral Infiltrating Carcinoma and/or Ductal Carcinoma in Situ in Patients Diagnosed with Flat Epithelial Atypia by Core Needle Biopsy (TBCRC 034)

Saturday, March 23, 2024

8:40am – 8:50am ET

Location: C101

Abstract Presenter(s)

Faina Nakhlis, MD

Breast Surgeon
Brigham and Women's Hospital, Dana-Farber Cancer Institute
Boston, Massachusetts, United States

Submitter(s)

Faina Nakhlis, MD

Breast Surgeon
Brigham and Women's Hospital, Dana-Farber Cancer Institute
Boston, Massachusetts, United States

Author(s)

Faina Nakhlis, MD

Breast Surgeon
Brigham and Women's Hospital, Dana-Farber Cancer Institute
Boston, Massachusetts, United States
GB

Gabrielle Baker, MD

Breast Pathologist
Beth Israel Deaconess Medical Center, United States
TL

Tianyu Li, MS

Biostatistician
Dana-Farber Cancer Institute, United States
RG

Rebecca Gelman, PhD

Biostatistician
Dana-Farber Cancer Institute, United States
GP

George Plitas, MD

Breast Service, Department of Surgery
Memorial Sloan Kettering Cancer Center, United States
Kandice K. Ludwig, MD

Associate Clinical Professor of Surgery
Indiana University, United States
PM

Priscilla McAuliffe, MD

Breast Surgical Oncologist
UPMC Hillman Cancer Center, United States
MB

Marc Boisvert, MD

Site director of the MedStar Breast Health Program
MedStar Washington Hospital Center, Georgetown University, United States
E. Shelley Hwang, MD, MPH

Mary and Deryl Hart Distinguished Professor of Surgery
Duke University School of Medicine
Durham, North Carolina, United States
Kristalyn K. Gallagher, DO (she/her/hers)

Surgical Director of the Breast Care Program
UNC School of Medicine
Chapel Hill, North Carolina, United States
LJ

Lisa Jacobs, MD

Division Chief, Breast Cancer Surgery
Johns Hopkins Medicine
Baltimore, MD, United States
SN

Suniti Nimbkar, MD

Medical Director, Breast Care Center
South Shore Hospital in clinical affiliation with Dana-Farber Brigham Cancer Center, United States
SF

Sheldon Feldman, MD

Chief, Division of Breast Surgery & Breast Surgical Oncology
Montefiore Medical Center, United States
PL

Paulina Lange, BS

-
Dana-Farber Cancer Institute, United States
VA

Victoria Attaya, BS

-
Dana-Farber Cancer Institute, United States
MD

Michelle DeMeo, BS

-
Dana-Farber Cancer Institute, United States
AF

Ashton Fraettarelli, BA

-
Dana-Farber Cancer Institute, United States
SS

Stuart Schnitt, MD

Chief of Breast Oncologic Pathology
Brigham and Women's Hospital, Dana-Farber Cancer Institute, United States
Tari A. King, MD (she/her/hers)

Chief, Division of Breast Surgery
Brigham and Women's Hospital, Dana-Farber Cancer Institute
Boston, Massachusetts, United States

Disclosure(s):

Faina Nakhlis, MD: No financial relationships to disclose

E. Shelley Hwang, MD, MPH: Exai Bio: Advisor (Ongoing)

Introduction:

Introduction: Flat epithelial atypia (FEA) is an uncommon lesion which is most often diagnosed on core biopsy (CB) of mammographic microcalcifications. Retrospective data suggest that FEA found on CB is associated with a wide range of upgrade to carcinoma (0-42%). We conducted a prospective multi-institutional trial (TBCRC 034) to determine the upgrade rate to ductal carcinoma in situ (DCIS) or invasive cancer at excision for FEA on CB.

Methods:

Methods: Patients (pts) with a BI-RADS <4 imaging abnormality and a concordant CB diagnosis of FEA were prospectively identified and consented to excision. Cases with additional lesions requiring excision were excluded. Upgrade rates were determined based on local and central pathology review. The prespecified threshold to omit excision of FEA on CB was an upgrade rate of <3%. Sample size and confidence intervals were based on exact binomial calculations.

Results:

Results: 129 pts were registered and had excision (median age 50 years, range 30-84 years). The most common imaging abnormality was mammographic calcifications (n=111, 86%). Per local pathology review, 6/129 cases (4.7%; 95% CI 1.7%-9.8%) were upgraded to invasive carcinoma (n=3) or DCIS (n=3) at excision. 116 (90%) CB cases were available for central pathology review and FEA was confirmed in only 78 of these cases (67.2%, 95% CI 57.9%-75.7%). The 38 cases excluded after central pathology review had benign changes other than FEA (n=11, 9.5%) or atypical ductal hyperplasia (ADH) (n=27, 23%). Central pathology review of these 78 excision specimens revealed only 1 upgrade to DCIS (1.3%, 95% CI 0.03%-6.9%), which was also one of the locally upgraded cases. Among the other 5 local upgrades, 2 cases did not have CB available for central review, 2 CB had ADH and 1 CB had normal tissue. If the 2 locally upgraded cases with unavailable CB slides were centrally confirmed to have FEA in the CB and to have an upgrade on excision, the central pathology upgrade rate would have been 3/80 (3.8%, 95% CI 0.8%-10.6%).

Conclusions:

Conclusions: In this prospective study of 129 pts with FEA on CB, the upgrade rate was 4.7% based on the local pathology review. However, among 78 cases confirmed as FEA on CB by central pathology review, the upgrade rate was only 1.3%. These results highlight the variability in the pathologic diagnosis of FEA, but also indicate that when the diagnosis of FEA on CB is confirmed by consensus review, the upgrade rate to DCIS or invasive carcinoma is extremely low.

Learning Objectives:
Upon completion, participants will learn the upgrade rate to carcinoma found on excision of flat epithelial atypia seen on core biopsy from a prospective single-arm trial.
Upon completion, participants will learn the correlation between local and central pathology for flat epithelial atypia.
Upon completion, participants will be able to appreciate the need for consensus pathology review of flat epithelial atypia diagnosis on core biopsy.