title: Mucocele-like lesions of the breast: a clinical outcome and histologic analysis of 102 cases.
abstract: Mucocele-like lesions (MLLs) of the breast are characterized by cystic architecture with stromal mucin and frequent atypia, but it is unknown whether they convey long-term breast cancer risk. We evaluated 102 MLLs that were derived from a single-institution benign breast disease cohort of 13412 women who underwent biopsy from 1967 to 2001. MLLs were histologically characterized by type of lining epithelium, architecture of the lesion, associated atypical hyperplasia (AH), and incidence of breast cancer (14.8-year median follow-up). A relatively large proportion of MLLs (42%) were diagnosed in women older than 55 years. AH was significantly more frequent in MLL patient compared to the cohort overall (27% versus 5%; P < .001). Breast cancer has developed in 13 patients with MLL. This frequency is only slightly higher than population expected rates overall (standardized incidence ratio, 2.28; 95% confidence interval, 1.21-3.91) and not significantly different from women in the cohort with (nonatypical) proliferative breast lesions. Younger women (<45) with MLL had a nonsignificant increase in risk of cancer compared to the general population (standardized incidence ratio, 5.16; 95% confidence interval, 1.41-13.23). We conclude that MLL is an uncommon breast lesion that is often associated with coexisting AH. However, in women older than 45 years, MLLs do not convey additional risk of breast cancer beyond that associated with the presence of proliferative disease.
authors.affiliation: Division of Anatomic Pathology, Mayo Clinic, Rochester, MN 55905.
authors.forename: Annie L
authors.initials: AL
authors.lastname: Meares
authors.affiliation: Division of Biomedical Statistics and Informatics, Mayo Clinic, Rochester, MN 55905.
authors.forename: Ryan D
authors.initials: RD
authors.lastname: Frank
authors.affiliation: Department of Surgery, Mayo Clinic, Rochester, MN 55905.
authors.forename: Amy C
authors.initials: AC
authors.lastname: Degnim
authors.affiliation: Division of Biomedical Statistics and Informatics, Mayo Clinic, Rochester, MN 55905.
authors.forename: Robert A
authors.initials: RA
authors.lastname: Vierkant
authors.affiliation: Department of Medical Oncology, Mayo Clinic, Rochester, MN 55905.
authors.forename: Marlene H
authors.initials: MH
authors.lastname: Frost
authors.affiliation: Department of Medical Oncology, Mayo Clinic, Rochester, MN 55905.
authors.forename: Lynn C
authors.initials: LC
authors.lastname: Hartmann
authors.affiliation: Division of Biomedical Statistics and Informatics, Mayo Clinic, Rochester, MN 55905.
authors.forename: Stacey J
authors.initials: SJ
authors.lastname: Winham
authors.affiliation: Division of Anatomic Pathology, Mayo Clinic, Rochester, MN 55905. Electronic address: visscher.daniel@mayo.edu.
authors.forename: Daniel W
authors.initials: DW
authors.lastname: Visscher
mesh_terms: D000328:Adult; D000367:Age Factors; D001706:Biopsy; D001940:Breast / Q000473:pathology*; D047688:Breast Cyst / Q000453:epidemiology / Q000473:pathology*; D001943:Breast Neoplasms / Q000453:epidemiology / Q000473:pathology*; D049109:Cell Proliferation; D005260:Female; D005348:Fibrocystic Breast Disease / Q000453:epidemiology / Q000473:pathology*; D006801:Humans; D006965:Hyperplasia; D015994:Incidence; D008875:Middle Aged; D008910:Minnesota / Q000453:epidemiology; D009078:Mucocele / Q000453:epidemiology / Q000473:pathology*; D012189:Retrospective Studies; D012307:Risk Factors; D013997:Time Factors
keywords: Atypical hyperplasia; Benign breast disease; Breast carcinoma; Columnar cell change; Fibrocystic breast disease; Mucoele-like lesion
references.citation: Am J Surg Pathol. 1986 Jul;10(7):464-9
references.pmid: 3014913
references.citation: Diagn Pathol. 2011 Apr 06;6:29
references.pmid: 21466711
references.citation: Am J Surg Pathol. 1996 Sep;20(9):1081-5
references.pmid: 8764744
references.citation: Am J Clin Pathol. 2012 Dec;138(6):783-8
references.pmid: 23161710
references.citation: Histopathology. 2013 May;62(6):894-8
references.pmid: 23402386
references.citation: Arch Pathol Lab Med. 1991 Feb;115(2):137-40
references.pmid: 1847035
references.citation: N Engl J Med. 2005 Jul 21;353(3):229-37
references.pmid: 16034008
references.citation: Mod Pathol. 2011 May;24(5):683-7
references.pmid: 21240257