Distinctive biology of pleomorphic lobular carcinoma of the breast

Invasive Pleomorphic Lobular Histology is an Adverse Prognostic Factor on Survival in Patients with Breast Cancer

Invasive pleomorphic lobular carcinoma (IPLC) is defined to be an uncommon and different subtype of classical invasive lobular carcinoma (ILC). This special variant is characterized by significant cytological atypia and pleomorphism which differs from the cytological uniformity of ILC. IPLC has been shown to have some poor prognostic factors such as axillary node metastasis and higher histological grade which may lead to poor clinical courses including a short relapse time, increased risk of recurrence and a decreased survival. The aim of this study is to investigate the clinicopathological characteristics and prognosis of IPLC in comparison with ILC and also to evaluate if IPLC is a different clinical entity compared to ILC. A total number of 4418 breast cancer patients treated between 1996 and 2015 in Hacettepe University Cancer Institute, were retrospectively analyzed. Among 4418 patients, 210 were diagnosed with ILC and 23 patients diagnosed with pure IPLC. In this present study, clinicopathological characteristics, disease free survival (DFS) and overall survival (OS) of patients with ILC and IPLC were compared. This study design is one of the rare face to face comparison of pure IPLC and ILC. Patients with IPLC had an increased rate of higher histologic grade, extracapsular extension, lymphovascular invasion and lower percentage of hormone positivity than those of patients with ILC. During the follow-up time, IPLC group experienced 4 cases (17.3%) of recurrence, 5 cases (21.7%) of death and 2 cases (8.7%) of progression in 3 metastatic patients compared to that of 27 cases (12.9%) of recurrence, 29 cases (13,8%) of death and 14 cases (6.7%) of progression in 19 metastatic patients in the ILC group. Patients with IPLC had a worse DFS and OS duration than patients with ILC (P = 0.02 for OS, P = 0.04 for DFS). In conclusion, IPLC is a different and a special breast cancer subtype. This study suggests that IPLC is a distinct clinical entity with an advanced stage and more aggressive clinical course. Patients with IPLC reveal poorer prognostic factors such as higher histological grade, relative lower percentages of hormone positivity, and increased rate of recurrences resulting in poor clinical outcomes and worse survival. Nowadays, it is observed that current treatment methods for IPLC do not seem as successful as in ILC and failed to be effective. Thence, individual therapies including more aggressive surgery and adjuvant or neoadjuvant chemotherapy even in the earlier stages of breast cancer should be performed for this distinct variant.

Invasive Pleomorphic Lobular Carcinoma of the Breast: Pathologic, Clinical, and Therapeutic Considerations

Pleomorphic lobular carcinoma is an uncommon form of breast cancer and a subtype of invasive lobular carcinoma. It has unique histopathologic features that translate to a more aggressive phenotype with an associated poor prognosis. Unlike classical invasive lobular carcinoma, it can lose estrogen and progesterone receptor expression and demonstrate HER-2/neu amplification. It remains to be determined, however, whether the pleomorphic histology independently predicts a worse outcome or whether other known associated negative prognostic factors such as larger tumor size, increased metastatic disease, and associated worse molecular subtypes commonly present in pleomorphic carcinoma account for the poor prognosis. Here we present an updated review of the unique pathologic and clinical features of pleomorphic lobular carcinoma needed to guide management for women with this subtype of cancer.

Clinical outcome in pleomorphic lobular carcinoma: a case-control study with comparison to classic invasive lobular carcinoma

Pleomorphic lobular carcinoma (PLC), a variant of invasive lobular carcinoma (ILC) is described as an aggressive tumor with poor prognosis. Multiple studies show lower overall survival for patients with PLC than for patients with classic ILC (cILC). We compared the clinicopathologic characteristics of PLC with those of cILC. All cases with a diagnosis of ILC, Nottingham grades 2 or 3 that were diagnosed between January 1, 1990, and December 31, 2010, were retrieved from pathology files in the institutional anatomic pathology database. The cases (N = 52) were reviewed to identify those meeting the criteria for PLC. An E-cadherin immunostain was used to confirm the lobular immunophenotype. Clinicopathologic data were assessed and analyzed. A control group (N = 103) of cILC, Nottingham grade 1, was selected, with 2 controls for each case, matched by age and year of diagnosis. PLC was associated more closely with in situ carcinoma (P = .03), and had lower progesterone receptor expression (P = .03) than cILC. Both disease-free survival and overall survival were similar between patients with PLC and matched cILC controls, and both depended on disease stage, tumor size, and lymph node status. PLC is similar to cILC in terms of patient survival and outcomes.

When is excision necessary for atypical lobular hyperplasia and lobular carcinoma in situ?

SUMMARY This management perspective briefly covers the histology and molecular features of lobular in situ neoplasia and provides an in-depth discussion of the need for surgical excision if lobular in situ neoplasia is diagnosed on core-needle biopsy. The management of lobular in situ neoplasia found on core-needle biopsy has been an area of recent study with varying results. Emerging data suggest that low-risk patients with a limited extent of isolated classic lobular in situ neoplasia found on core-needle biopsy may not require subsequent surgical excision. However, high-risk patients, those with extensive lobular in situ neoplasia, or other high-risk lesions noted on core-needle biopsy likely benefit from surgical excision. Most authors recommend surgical excision when pleomorphic lobular carcinoma in situ is found on core-needle biopsy due to its higher association with invasive carcinoma. However, the natural history of this more recently described variant of lobular carcinoma in situ is not fully defined, and the clinical management of pleomorphic lobular carcinoma in situ on excisional biopsy is yet to be determined.

Pleomorphic lobular carcinoma of the breast: a morphologically and clinically distinct variant of lobular carcinoma

Pleomorphic lobular carcinoma is an uncommon variant of lobular carcinoma, characterized by significant cytologic atypia that contrasts with the low pleomorphism of classical lobular carcinoma. It accounts for approximately 1% of all epithelial breast malignancies. In addition to its pleomorphism, it is characterized by aggressive behavior and shortened patient survival. Although the morphologic features of pleomorphic lobular carcinoma are well described, it often eludes accurate pathologic characterization. Some controversy surrounds the pathogenesis of pleomorphic lobular carcinoma; however, it is now considered a well-defined variant of invasive lobular carcinoma. Pleomorphic lobular carcinoma shares molecular alterations with classical lobular carcinoma, such as alterations in the gene CDH1 on chromosome band 16q22 that results in changes in E-cadherin protein function. The aggressive biology of pleomorphic lobular carcinoma relates to the acquisition of genetic alterations typical of high-grade ductal carcinoma, such as overexpression of HER2/neu and c-myc.

Pleomorphic lobular carcinoma of the breast: molecular pathology and clinical impact

Pleomorphic lobular carcinoma of the breast is a recently described morphological variant of classic invasive lobular carcinoma with an aggressive behavior. Morphologically, pleomorphic lobular carcinoma elicits a similar pattern of infiltrative growth as invasive lobular carcinoma, yet neoplastic cells have marked nuclear atypia and pleomorphism. Pleomorphic lobular carcinoma and the in situ counterpart, pleomorphic lobular carcinoma in situ, are frequently hormone receptor (estrogen-, progesterone- and androgen-receptor)-positive and E-cadherin and β-catenin-negative, attaining to their lobular nature. Tumors can also be positive for HER2, p53, ki67 and GCDFP-15 and harbor frequent chromosomal alterations involving gains on 1q and 16p, losses on 11q and 16q, and genomic amplifications in the region of 8q24, 11q13, 12q13, 17q12 and 20q13. Recent gene-expression profiling classified pleomorphic lobular carcinoma as ‘molecular apocrine’ tumors reflecting the frequent apocrine differentiation of the tumors. In support for the aggressive biological features described for pleomorphic lobular carcinoma, accumulating clinical data demonstrate that it has an aggressive clinical course. It is now important to define the most appropriate management strategy for patients diagnosed with pleomorphic lobular carcinoma.

Molecular and Morphologic Distinctions between Infiltrating Ductal and Lobular Carcinoma of the Breast

Histopathologic distinction between ductal and lobular carcinomas of the breast has been made since 1941. Together, these two subtypes account for >95% of all mammary carcinomas. With the recent advances in molecular techniques, our understanding of the biology behind these carcinomas has greatly expanded. The genomic aberrations in mammary carcinoma are highly complex and appear to be more associated with tumor grade rather than any histopathologic subtype. Protein and RNA expression profiling reveals a classification of mammary carcinoma that has some overlap with traditional histopathology and can at least partially explain clinical behavior. The goal of this review is to present what is currently known about the molecular profiles of infiltrating ductal and lobular carcinoma and how they relate to conventional histopathology and biologic behavior.