Journal Article
. 2018 Feb; 71(8):672-679.
doi: 10.1136/jclinpath-2017-204977.

Interobserver variation in the diagnosis of fibroepithelial lesions of the breast: a multicentre audit by digital pathology

Benjamin F Dessauvagie 1 Andrew H S Lee 2 Katie Meehan 3 Anju Nijhawan 1 Puay Hoon Tan 4 Jeremy Thomas 5 Bibiana Tie 6 Darren Treanor 1 Seemeen Umar 1 Andrew M Hanby 1 Rebecca Millican-Slater 1 
Affiliations
  • PMID: 29440134
  •     5 citations

Abstract

Aim: Fibroepithelial lesions (FELs) of the breast span a morphological continuum including lesions where distinction between cellular fibroadenoma (FA) and benign phyllodes tumour (PT) is difficult. The distinction is clinically important with FAs managed conservatively while equivocal lesions and PTs are managed with surgery. We sought to audit core biopsy diagnoses of equivocal FELs by digital pathology and to investigate whether digital point counting is useful in clarifying FEL diagnoses.

Method: Scanned slide images from cores and subsequent excisions of 69 equivocal FELs were examined in a multicentre audit by eight pathologists to determine the agreement and accuracy of core needle biopsy (CNB) diagnoses and by digital point counting of stromal cellularity and expansion to determine if classification could be improved.

Results: Interobserver variation was high on CNB with a unanimous diagnosis from all pathologists in only eight cases of FA, diagnoses of both FA and PT on the same CNB in 15 and a 'weak' mean kappa agreement between pathologists (k=0.36). 'Moderate' agreement was observed on CNBs among breast specialists (k=0.44) and on excision samples (k=0.49). Up to 23% of lesions confidently diagnosed as FA on CNB were PT on excision and up to 30% of lesions confidently diagnosed as PT on CNB were FA on excision. Digital point counting did not aid in the classification of FELs.

Conclusion: Accurate and reproducible diagnosis of equivocal FELs is difficult, particularly on CNB, resulting in poor interobserver agreement and suboptimal accuracy. Given the diagnostic difficulty, and surgical implications, equivocal FELs should be reported in consultation with experienced breast pathologists as a small number of benign FAs can be selected out from equivocal lesions.

Keywords: breast pathology; digital pathology; fibroadenoma; fibroepithelial lesions; phyllodes tumour; quality assurance.

Fibroepithelial Lesions (FELs) of the Breast: Is Routine Excision Always Necessary?
Jessica Limberg, Kelly Barker, +3 authors, Jennifer L Marti.
World J Surg, 2020 Jan 25; 44(5). PMID: 31974650
Histopathologic, immunophenotypic, and proteomics characteristics of low-grade phyllodes tumor and fibroadenoma: more similarities than differences.
Lingxin Zhang, Chen Yang, +6 authors, Horacio M Maluf.
NPJ Breast Cancer, 2020 Jul 03; 6. PMID: 32613078    Free PMC article.
The Use of Screencasts with Embedded Whole-Slide Scans and Hyperlinks to Teach Anatomic Pathology in a Supervised Digital Environment.
Mary Wong, Joseph Frye, Stacey Kim, Alberto M Marchevsky.
J Pathol Inform, 2019 Jan 05; 9. PMID: 30607306    Free PMC article.
Fibroepithelial lesions revisited: implications for diagnosis and management.
Puay Hoon Tan.
Mod Pathol, 2020 May 29; 34(Suppl 1). PMID: 32461622
Review.
Morphologic and genetic heterogeneity in breast fibroepithelial lesions-a comprehensive mapping study.
Benjamin Yongcheng Tan, Nur Diyana Md Nasir, +9 authors, Puay Hoon Tan.
Mod Pathol, 2020 Apr 24; 33(9). PMID: 32322022