Mucinous / colloid carcinoma

Breast malignant, males, children
Carcinoma subtypes
Mucinous / colloid carcinoma

Author: Monika Roychowdhury, M.D. (see Authors page)

Revised: 29 December 2016, last major update August 2012

Copyright: (c) 2002-2016, PathologyOutlines.com, Inc.

PubMed search: Mucinous carcinoma [title] breast

Table of Contents

Cite this page: Mucinous / colloid carcinoma. PathologyOutlines.com website. http://www.pathologyoutlines.com/topic/breastmalignantmucinous.html. Accessed July 14th, 2017.

Definition / general

Clusters of small uniform cells floating in lakes of extracellular mucin
Mucin accumulation may be due to inversion of polarity in cell, with mucin secretion directed towards base of cell / stroma, rather than luminal border
Tumor cells also produce MUC2, a distinctive mucin type (Am J Surg Pathol 2003;27:571, Hum Pathol 1998;29:1517, Histopathology 2003;42:26)
Classified as type A (paucicellular / no neuroendocrine differentiation), type B (hypercellular / neuroendocrine differentiation) or type AB (intermediate form), although no clinical significance
Based on molecular studies, mucinous type A is distinct from mucinous type B, and mucinous type B is part of a spectrum with neuroendocrine carcinoma (Mod Pathol 2009;22:1401)
Pure if 90% of more mucinous / colloid component
Cases with 75% - 90% mucinous / colloid component are considered a mixed variant with a prognosis worse than pure mucinous carcinoma, and dependent on the grade of the remaining carcinoma component
Dictionary definition of colloid:
- a. gelatinous material resulting from colloid degeneration in diseased tissue;
- b. resembling product of thyroid gland;
- c. system in which finely divided particles are dispersed within a continuous medium in a manner that prevents them from being filtered easily or settled rapidly

Terminology

Also called gelatinous carcinoma

Epidemiology

0.5% to 3% of breast carcinomas (Cancer Radiother 2009;13:37)
Usually older women (mean age 71 years, Breast Cancer Res Treat 2008;111:541) with slow growing tumor

Clinical features

Nodal metastases are rare (2% - 4%), but important prognostic factor (Am J Surg 2004;187:528)
Usually no nodal metastases for tumors < 1 cm (Am J Surg 2008;196:549)
Micropapillary architecture has no clincal significance (Int J Surg Pathol 2008;16:251, but see Breast J 2008;14:412)

Prognostic factors

10 year survival for pure form is > 90% (much better than ductal carcinoma NOS)
Death may occur late, although 20 year breast cancer specific survival is still > 80%

Case reports

35 year old woman with locally advanced mucinous carcinoma of the breast with sudden growth acceleration (Jpn J Clin Oncol 2002;32:64)
36 year old woman with invasive mucinous carcinoma arising within breast fibroadenoma (Pathologica 2008;100:199)
42 year old woman with recurrent pure mucinous carcinoma of the breast with mediastinal great vessel invasion (Am Surg 2008;74:113)
47 year old woman with mucinous adenocarcinoma of ectopic breast tissue of the vulva (Arch Pathol Lab Med 2002;126:1216)
64 year old woman with a case of nonmetastatic giant mucinous carcinoma of the breast (Breast Cancer 2005;12:337)
74 year old man with pure mucinous (colloid) carcinoma of the male breast (Gac Med Mex 2007;143:79)
86 year old man with mucinous breast carcinoma presenting as Paget's disease of the nipple in a man (Diagn Pathol 2008;3:42)
Woman in 60's with a breast mass (Case of the Week #11)

Treatment

Pure cases may not need axillary staging (Ann Surg Oncol 2002;9:161)

Clinical images

Images hosted on PathOut server:

Mammogram, courtesy of Dr. Mark R. Wick

Gross description

Soft, pale, grayish blue, gelatin-like and well circumscribed
Frequently hemorrhagic

Gross images

Images hosted on PathOut server:

Pure, courtesy of Dr. Mark R. Wick

AFIP

Images hosted on other servers:

Gelatinous or jelly-like cut surface

Ill defined margins

Tumor with positive margin (Fig 1A / 1B)

Soft, gelatinous mass

Microscopic (histologic) description

Well differentiated (low grade) tumor cells floating in a sea of lightly staining amorphous mucin
Tumor cells may be solid, acinar or detached
Often surrounded by connective tissue bands
Recommended that at least 1/3 of tumor volume should consist of mucin, and that no areas of typical invasion should be present (Pure Mucinous Carcinoma of the Breast - Stanford University)
No / rare mitotic figures
Usually no in situ epithelial component
Note: recommended to designate tumors as pure (at least 90% mucinous component) or mixed

Microscopic (histologic) images

Scroll to see all images.

Images hosted on PathOut server:

Pure, courtesy of Dr. Mark R. Wick

Mucicarmine stain, courtesy of Dr. Mark R. Wick

Parenchyma, courtesy of Dr. Mark R. Wick

Case of the Week #11:

AFIP images:

Alveolar and festoon patterns surrounded

Sparse epithelial component (arrow - DCIS) by mucin

Clusters of tumor cells
in mucinous secretion
surround a duct

Clusters of tumor cells

Grimelius staining (an agryophilic silver stain) denotes neuroendocrine differentiation

Images hosted on other servers:

Nuclear atypia is mild

Nuclear grading of intermediate

Abundant mucinous stroma containing epithelial tumor cells with at most mild atypia

Cells in pools of extracellular mucin

Mucin is extracellula

Irregular nests and clusters of tumor cells

Nuclei are plump and vesicular

Anastomosing nests

Well differentiated tumor cells

Cribriform pattern

Small clusters of tumor cells

Contributed by: Dr. Semir Vranic, University of Sarajevo (Bosnia)

Tumor cells are ER+

H&E, CU-18

EMA

H&E

Cytology description

Highly cellular, loosely cohesive clusters and dissociated cells with intact cytoplasm and nuclei with mild atypia, no oval bare nuclei
Also thin walled capillaries, micropapillary pattern of angulated clusters or abortive papillae and ball-like clusters (Acta Cytol 2007;51:25), abundant extracellular mucin (Malays J Pathol 2000;22:65)
May have spindle cells at edge of nests and in background, which represent either tumor cells compressed by mucin or fibroblasts (Diagn Cytopathol 2009;37:393)
Variable psammoma bodies (Diagn Cytopathol 2007;35:230)

Cytology images

Images hosted on PathOut server:

Grimelius stain, courtesy of Dr. Mark R. Wick

Images hosted on other servers:

Papanicolaou

Various images

Colloid carcinoma

Nature.com images:

MGG

Positive stains

ER, PR (< 70%) and MUC2
Neuroendocrine differentiation (chromogranin, synaptophysin, neuron specific enolase) in 15% - 50% (Am J Surg Pathol 1994;18:702)
Mucin stains with PAS, alcian blue and mucicarmine
Also WT1 (65%, Mod Pathol 2008;21:1217), androgen receptor (42%, Ann Oncol 2010;21:488)

Negative stains

MUC1 (or low, Histopathology 2003;42:26)
p53
HER2 (Kaohsiung J Med Sci 2005;21:197)

Electron microscopy description

Differences exist between cells of pure and mixed forms (Ultrastruct Pathol 2007;31:263)

Electron microscopy images

Images hosted on PathOut server:

Cytoplasmic mucigen granules

Molecular / cytogenetics description

Usually diploid

Videos

Histopathology Breast—Colloid carcinoma

Differential diagnosis

Infiltrating ductal carcinoma with focal mucinous change
Invasive micropapillary carcinoma: less extracellular mucin than mucinous carcinoma; cells have abundant eosinophilic cytoplasm, round vesicular nuclei and prominent nucleoli; extensive true angiolymphatic invasion; often psammoma bodies
Metastatic mucinous carcinoma (rectum - Asian J Surg 2006;29:95)
Mucinous ductal carcinoma in situ: noninvasive, myoepithelial cells (calponin+, p63+) are present
Mucocele-like lesion: myoepithelial cells are present and adherent to strips of cells floating in mucin, also ducts extended by mucinous material
Myxoid fibroadenoma: has compressed spaces lined by 2 layers
Signet ring carcinoma: intracellular mucin only
FNA: infiltrating ductal carcinoma: marked atypia (Am J Clin Pathol 2003;120:194)
FNA: myxoid fibroadenoma: stromal fragments and oval bare nuclei in every case