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Non-enzymatic, Serum-free Tissue Culture of Pre-invasive Breast Lesions for Spontaneous Generation of Mammospheres
Published on: November 8, 2014
Invasive Micropapillary Carcinoma of the Breast: An Update
Yi-Ling Yang, Bing-Bing Liu, Xinmin Zhang
1From the Department of Breast Pathology and Research Laboratory, Key Laboratory of Breast Cancer Prevention and Therapy, Ministry of Education, National Clinical Research Center for Cancer, Tianjin Medical University Cancer Institute and Hospital, Tianjin, China (Drs Yang, Liu, and Fu); and the Department of Pathology, Cooper University Hospital, Cooper Medical School of Rowan University, Camden, New Jersey (Dr Zhang). Drs Zhang and Fu jointly supervised the work.
Context:
-Invasive micropapillary carcinoma (IMPC) is a distinct variant of mammary carcinoma in which tumor cells are arranged in morulelike clusters devoid of fibrovascular cores and situated within empty stromal spaces. Identification of IMPC can be achieved by the assessment of morphologic features in conjunction with the characteristic "inside-out" staining pattern of epithelial membrane antigen and sialyl Lewis X highlighted by immunohistochemical analysis. Although recognizing micropapillary architecture is often not challenging, the criteria for distinguishing between mixed and pure IMPC remain imprecise. Some mucin-producing carcinomas can also have micropapillary histology, but there is no consensus on whether these tumors are variants of IMPC or mucinous carcinomas. The molecular genetic studies demonstrate that IMPCs have distinct molecular genetic profiles, supporting the theory that they constitute distinct pathologic entities. However, genomic analyses have not identified any specific genomic aberration that may explain the distinctive morphology and clinical behavior of IMPC.
Objective:
-To provide an overview on the current concepts in the diagnosis and pathogenesis of IMPC of the breast, incorporating recent molecular genetic advances and prognosis-based reclassification.
Data Sources:
-PubMed search and the cited references were reviewed.
Conclusions:
-The recent evolution of prognosis-based reclassification and molecular genetic advances has enhanced our knowledge of the pathogenesis of IMPC of the breast. Additional studies might reveal consistent molecular alterations that underlie the formation of the inside-out growth pattern, and they might elucidate the molecular mechanisms responsible for the unfavorable clinical behavior of IMPC.
Insights
Invasive micropapillary carcinoma (IMPC) is a unique breast cancer subtype. Recent advances in molecular genetics and prognosis-based reclassification improve understanding of its pathogenesis and clinical behavior.
Area of Science:
- Oncology
- Pathology
- Genetics
Background:
- Invasive micropapillary carcinoma (IMPC) is a distinct breast cancer variant characterized by morule-like clusters lacking fibrovascular cores within empty stromal spaces.
- Diagnosis relies on morphology and immunohistochemistry, specifically the "inside-out" staining pattern of epithelial membrane antigen and sialyl Lewis X.
- Distinguishing pure from mixed IMPC and its relationship with mucin-producing carcinomas remain areas of imprecision.
Purpose of the Study:
- To review current diagnostic and pathogenetic concepts of IMPC.
- Incorporate recent molecular genetic findings and prognosis-based reclassifications.
- Provide an updated overview of IMPC of the breast.
Main Methods:
- Literature review of PubMed and cited references.
- Synthesis of current knowledge on IMPC diagnosis and pathogenesis.
- Analysis of recent molecular genetic and prognostic data.
Main Results:
- IMPCs exhibit distinct molecular genetic profiles, supporting their classification as separate entities.
- Genomic analyses have not yet identified specific aberrations explaining IMPC's unique morphology or behavior.
- Prognosis-based reclassification and molecular advances have enhanced understanding of IMPC pathogenesis.
Conclusions:
- Recent molecular and prognostic reclassification advances have improved understanding of IMPC pathogenesis.
- Further research is needed to identify molecular alterations driving the "inside-out" growth pattern.
- Future studies may elucidate mechanisms behind IMPC's unfavorable clinical behavior.
