Preoperative Magnetic Resonance Imaging Features Associated with Positive Resection Margins in Patients with Invasive Lobular Carcinoma

Abstract

Objective To investigate preoperative magnetic resonance imaging (MRI) findings associated with resection margin status in patients with invasive lobular carcinoma (ILC) who underwent breast-conserving surgery. Materials and Methods One hundred and one patients with ILC who underwent preoperative MRI were included. MRI (tumor size, multifocality, type of enhancing lesion, distribution of non-mass enhancement [NME], and degree of background parenchymal enhancement) and clinicopathological features (age, pathologic tumor size, presence of ductal carcinoma in situ [DCIS] or lobular carcinoma in situ , presence of lymph node metastases, and estrogen receptor/progesterone receptor/human epidermal growth factor receptor type 2 status) were analyzed. A positive resection margin was defined as the presence of invasive cancer or DCIS at the inked surface. Logistic regression analysis was performed to determine pre- and postoperative variables associated with positive resection margins. Results Among the 101 patients, 21 (20.8%) showed positive resection margins. In the univariable analysis, NME, multifocality, axillary lymph node metastasis, and pathologic tumor size were associated with positive resection margins. With respect to preoperative MRI findings, multifocality (odds ratio [OR] = 3.977, p = 0.009) and NME (OR = 2.741, p = 0.063) were associated with positive resection margins in the multivariable analysis, although NME showed borderline significance. Conclusion In patients with ILC, multifocality and the presence of NME on preoperative breast MRI were associated with positive resection margins.

How to Clearly and Accurately Report Odds Ratio and Hazard Ratio in Diagnostic Research Studies?

“…When 34 original research studies reporting OR published in the Korean Journal of Radiology in 2020–2021 [ 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 ] were evaluated against a rigorous standard (i.e., complete transparency in reporting), 91.2% (31/34) clearly mentioned how they defined the odds, 62.1% (18/29) unmistakably described the reference category for OR calculation for categorical variables, and 42.9% (9/21) specified the one-unit amount for OR for continuous variables. Therefore, there is room for improvement in reporting.…”

“…Figure 2 shows slightly different styles to clearly and accurately report OR or HR [ 19 41 45 ]. Examples can be found in other published articles [ 15 28 33 37 38 52 59 62 ].…”

Discriminative Factors of Malignancy of Ipsilateral Nonmass Enhancement in Women With Newly Diagnosed Breast Cancer on Initial Staging Breast MRI

“…[11][12][13][14][15] Nonmass enhancement (NME) is a common finding in preoperative breast MRI, accounting for 32% of additional cancer sites in the ipsilateral breast from previous published data. 16 Prior studies also revealed that malignant NME was one of the leading causes of positive resection margins in BCS with or without an accompanying mass [17][18][19] and was associated with intraductal extension of the invasive cancer. 20 However, the high false-positive rate of NME 8,21,22 may prompt unnecessary biopsies and treatment delay of breast cancer, leading to dispute over the benefits of preoperative MRI.…”

“…To date, most of prior studies evaluating breast MRI for staging in newly diagnosed breast cancer patients have focused on all types of additional MRI findings, including masses in the ipsilateral breast with only a small number of studies evaluating ipsilateral NME, most of which are located adjacent to cancer. [17][18][19][20]26,27 There is limited data whether detection of NME in the ipsilateral breast that is non-adjacent to the known cancer is benign or malignant. In addition, the new BI-RADS lexicon will specifically comment on separate additional findings in the ipsilateral breast versus current known cancer.…”

“…The current fifth edition of ACR BI‐RADS® descriptors for NME have shown to be insufficient for characterization between malignant and benign lesions, as MRI features can greatly overlap and subject to interobserver variability, 23–25 potentially leading to false‐positive diagnosis, more extensive surgery, and patient anxiety. To date, most of prior studies evaluating breast MRI for staging in newly diagnosed breast cancer patients have focused on all types of additional MRI findings, including masses in the ipsilateral breast with only a small number of studies evaluating ipsilateral NME, most of which are located adjacent to cancer 17–20,26,27 . There is limited data whether detection of NME in the ipsilateral breast that is non‐adjacent to the known cancer is benign or malignant.…”