Evolving concepts in breast lobular neoplasia and invasive lobular carcinoma, and their impact on imaging methods

Abstract

Invasive lobular carcinoma (ILC) and lobular neoplasia (LN) are two distinct conditions that still pose challenges regarding to their classification, diagnosis and management. Although they share similar cellular characteristics, such as discohesive neoplastic cells and absence of e-cadherin staining, they represent completely different conditions. LN encompasses atypical lobular hyperplasia (ALH) and lobular carcinoma in situ (LCIS), which are currently considered risk factors and non-obligatory precursors of breast neoplasia. These lesions are diagnosed as incidental findings in percutaneous biopsies or appear as non-specific clusters of punctate calcifications in mammograms. ILC is the second most common breast malignancy and has typical histological features, such as infiltrative growth and low desmoplasia. These histological features are reflected in imaging findings and constitute the reasons for typical subtle mammographic features of ILC, as architectural distortion or focal asymmetries. Ultrasonography (US) may detect almost 75 % of the ILCs missed by mammography and represents the modality of choice for guiding biopsies. Magnetic resonance imaging (MRI) exhibits a high sensitivity for the diagnosis of ILC and for detecting synchronous lesions.Teaching Points• LN includes ALH and LCIS, risk factors and non-obligatory precursors of breast cancer.• Absence of e-cadherin staining is crucial for differentiation among ductal and lobular lesions.• ILC has typical histological features, such as infiltrative growth and low desmoplasia.• Mammographic features of ILC are often subtle and reflect the histological features.• MRI exhibits a high sensitivity for the diagnosis of ILC and for detecting synchronous lesions.

Breast Density Notification Legislation and Breast Cancer Stage at Diagnosis: Early Evidence from the SEER Registry

“…We excluded women with a diagnosis of lobular carcinoma in situ (LCIS), as LCIS is typically not detected during screening. 19 We also excluded women who had unstaged cancer. We excluded data from counties affected by Hurricane Katrina in 2005, which are not considered part of the standard SEER data set.…”

Unifocal Invasive Lobular Carcinoma: Tumor Size Concordance Between Preoperative Ultrasound Imaging and Postoperative Pathology

“…The lack of radiation and real-time nature of the ultrasound makes it the method of choice for image-guided procedures 3,6 . There is increasing evidence that ultrasound can detect occult cancers 6,8 . Typically, ILC has a low mammographic sensitivity varying from 57–79 %, reflecting one of the most important causes of false negative rates 8 .…”

“…There is increasing evidence that ultrasound can detect occult cancers 6,8 . Typically, ILC has a low mammographic sensitivity varying from 57–79 %, reflecting one of the most important causes of false negative rates 8 . Also, for patients diagnosed with ILC, tumor size from mammography ( r =0.27) is poorly correlated with histopathology 9 .…”

Influence of Tumor Subtype, Radiological Sign and Prognostic Factors on Tumor Size Discrepancies Between Digital Breast Tomosynthesis and Final Histology

“…It is possible that the coexistence of infiltrating lobular carcinoma at histology and architectural parenchimal distortion at imaging finding represent the combination with greater risk of discrepancies in the exact definition of tumor size. Indeed, invasive lobular carcinoma (ILC) is the most common "special" type of breast cancer (approximately 5-15% of all breast cancers) with a characteristic grow pattern involving the infiltration of single cells or single files of cells through the stroma, with little alterations of normal tissue architecture and relative preservation of normal breast parenchymal architecture [18]. The complex biology of ILC is probably one of the possible explanations of tumor size discrepancies among DBT and final histology.…”