Histologic Analysis and Diagnostic Yield of Breast SCNB

In This Article

Abstract and Introduction

Abstract

Objectives: Stereotactic core needle biopsy (SCNB) is used in the diagnostic assessment of suspicious mammographic calcifications to rule out breast ductal carcinoma in situ (DCIS). With advances in imaging technology and increased biopsy tissue volume, the detection rate of calcifications and DCIS in SCNB is unclear.

Methods: This retrospective study included 916 consecutive SCNBs for calcifications performed on 893 patients in a 2-year period.

Results: We found the cancer detection rate was 27.1% (DCIS, 23.7%; invasive, 3.4%). The detection rate for calcifications was 74.8% with the standard 3 levels. Additional leveling of calcification-negative cases further increased the detection of both calcifications (to 99.4% of cases) and DCIS (to 32.9% of cases). Lobular neoplasia (LN) was diagnosed in 41 cases. Twenty-five (61.0%) cases of LN were incidental without associated calcification. Of 32 invasive carcinomas detected on SCNB, 87.5% were T1a or less, and calcifications were associated with atypical ductal hyperplasia/DCIS or LCIS. The common benign lesions associated with calcifications were fibrocystic change (32.5%), fibroadenomatous change (30.2%), and columnar cell change and hyperplasia (8.2%).

Conclusions: We determined the up-to-date detection rates of calcification and DCIS in SCNB, as well as the common benign and malignant breast lesions associated with calcifications. Additional levels significantly increase the detection rate when standard levels show only stromal or scant/absent calcifications. Lobular neoplasia is often an incidental finding in SCNB for calcifications. When calcifications are present with LN, they are commonly florid, pleomorphic LCIS, or with concurrent invasive carcinoma.

Introduction

Stereotactic core needle biopsy (SCNB) is mainly used for mammographic detected suspicious calcifications to rule out ductal carcinoma in situ (DCIS). The diagnostic yield from the standard initial histologic sections is an unanswered question, and the literature is very scant. The most recent study on histologic levels' effect on detecting calcification and DCIS was decades ago.^[1,2]

Over the past 20 years, imaging techniques have improved dramatically. Image resolution and detection rates have significantly increased with technological developments in tomosynthesis and magnetic resonance imaging (MRI). Stereotactic, ultrasound, and MRI-guided biopsies have improved localization and resulted in the better sampling of targeted areas. Nowadays, the 9-gauge vacuum-assisted SCNB has replaced the 14-gauge automated stereotactic biopsy, significantly increasing the amount of tissue material available for histologic analysis. Despite the significant change in the imaging and sampling technologies, studies are scant regarding performance evaluation. They need to be updated based on the current understanding of the importance of radiopathology correlation for calcifications and the rate of DCIS detection to date.^[3–5]

With our institutional volume of 1,500 breast biopsies per year, we studied the histologic yield of SCNBs performed for calcification. We aimed to determine the following: (1) the vacuum-assisted biopsy yield of DCIS in the current age, (2) whether additional levels in the search for calcifications improve diagnostic accuracy and change the clinical management, and (3) the common histologic characteristics of lesions associated with calcifications.

Table 1. Summary of All Cases
Characteristic	Cases, No. (% Total)	Age, Mean (Range), y	Laterality: R, L, No.
Total	916	57.3 (30–91)	476, 440
Surgery
INV	32 (3.4)	64.0^a (41–76)	14, 17
DCIS	218 (23.7)	60.8 (31–91)	112, 106
ADH	99 (10.8)	57.5 (31–82)	55, 44
Maybe surgery
FEA	5 (0.5)	52.4 (44–60)	4, 1
ALH/LCIS	37 (4.2)	57.8 (38–83)	19, 18
No surgery
FCC, FA, CCC	523 (57.0)	58.2 (30–86)	272, 251

ADH, atypical ductal hyperplasia; ALH, atypical lobular hyperplasia; CCC, columnar cell change; DCIS, ductal carcinoma in situ; FA, fibroadenomatous/fibroadenomatoid change; FCC, fibrocystic change; FEA, flat epithelial atypia; INV, invasive; L, left; LCIS, lobular carcinoma in situ; R, right.
^aStatistically significant (P < .05) by t test.

Table 2. Summary of the 36 Cases With Change of Diagnosis After Levels
No. of Cases	Initial Diagnosis	Initial Management	Additional Level	Final Management
Change of diagnosis without change of management (n = 11)
4	Benign	No excision	ALH	No excision
2	FEA	Excision	ADH	Excision
2	Benign	Excision^a	DCIS	Excision
3	ADH	Excision	DCIS	Excision
Change of diagnosis with change of managements (n = 25)
1	Benign	No excision	FEA	Maybe excision
10	Benign	No excision	ADH	Excision
8	Benign	No excision	DCIS	Excision
1	Benign	No excision	LCIS	Maybe excision
5	Stromal calc	No excision	DCIS	Excision

ADH, atypical ductal hyperplasia; ALH, atypical lobular hyperplasia; DCIS, ductal carcinoma in situ; FEA, flat epithelial atypia; LCIS, lobular carcinoma in situ.
^aADH on other tissue block.

Table 3. Summary of the Lobular Neoplasia Cases (n = 41)
Characteristic	Total	ALH	LCIS	Type of LCIS
Incidental LN^a	25	17	8	8 classic
Calcifications with LN	16	2	14	8 classic (1 with concurrent ILC)
				4 florid (1 with concurrent ILC)
				2 pleomorphic (2 with concurrent ILC)

ALH, atypical lobular hyperplasia; ILC, invasive lobular carcinoma; LCIS, lobular carcinoma in situ; LN, lobular neoplasia.
^aIncidental LN: LN present where the calcifications associated with benign epithelium and/or DCIS.