Department of Cellular Pathology, St James's University Hospital, Leeds Teaching Hospitals NHS Trust, Leeds, UK.
Leeds Institute of Cancer and Pathology, St James's University Hospital, Leeds University, Leeds, UK.
J Clin Pathol. 2018 Aug;71(8):672-679. doi: 10.1136/jclinpath-2017-204977. Epub 2018 Feb 13.
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.
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.
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.
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.
乳腺纤维上皮性病变（FEL）呈形态学连续谱，包括细胞性纤维腺瘤（FA）和良性叶状肿瘤（PT）之间难以区分的病变。这种区分具有临床重要性，FA 采用保守治疗，而不确定的病变和 PT 则采用手术治疗。我们试图通过数字病理学审核核心活检诊断为不确定的 FEL，并研究数字点计数是否有助于澄清 FEL 诊断。
在一项多中心审核中，由 8 位病理学家检查了 69 例不确定的 FEL 核心活检和随后的切除标本的扫描切片图像，以确定核心针活检（CNB）诊断的一致性和准确性，以及通过数字点计数评估间质细胞密度和扩张程度，以确定是否可以改善分类。
在 CNB 上观察者间变异很高，只有 8 例 FA 得到所有病理学家的一致诊断，15 例同时诊断为 FA 和 PT，病理学家之间的平均kappa 一致性（κ=0.36）较弱。在乳腺专家（κ=0.44）和切除标本上（κ=0.49）观察到 CNB 之间的“中度”一致性。多达 23%的在 CNB 上明确诊断为 FA 的病变在切除时为 PT，多达 30%的在 CNB 上明确诊断为 PT 的病变在切除时为 FA。数字点计数无助于 FEL 的分类。
不确定的 FEL 的准确和可重复诊断很困难，尤其是在 CNB 上，导致观察者间的一致性较差和准确性不理想。鉴于诊断困难和手术影响，应在与经验丰富的乳腺病理学家协商下报告不确定的 FEL，因为可以从不确定的病变中选择出少数良性 FA。
