33 Special Types of Invasive Breast Carcinoma: Diagnostic Criteria ...

Case 3:
History: A 73 year old female with history of breast mass found by
mammogram underwent percutaneous ultrasound-guided core biopsy of the
left breast mass
Submitted diagnosis: Invasive tubular carcinoma (well-differentiated invasive
breast carcinoma, overall mBR grade 1; nuclear grade 1, tubular grade 1,
mitotic grade 1).
TUBULAR AND CRIBRIFORM CARCINOMA
Background: Tubular carcinoma is a well-differentiated (mBR grade 1) invasive
carcinoma with regular cells arranged in well-defined tubules typically one layer thick
and surrounded by an abundant fibrous stroma. Tubular carcinoma should not be
confused with invasive ductal carcinomas with gland-like structures whose cells are
less well differentiated (1,2). Pure tubular carcinomas constitute at least 2% of all
breast carcinomas (3-5) and they are being seen with increasing frequency as a result
of screening mammography. Likewise, cribriform carcinoma is a well-differentiated
(mBR grade 1) variant of invasive breast carcinoma, in which the majority of the
invasive component grows in an irregular cribriform pattern, often admixed with
features of well-differentiated tubular carcinoma. Approximately 6% of invasive
mammary carcinomas have a cribriform element with nearly equal proportions of
"pure" and "mixed" lesions (6,7). When the tubular component is less than 50%, some
advocate use of the term “invasive cribriform carcinoma;” when over 50%, then
“invasive tubular carcinoma” is suggested as more appropriate (6-8). But, because of
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