AJR 2000; 174:757-761
© American Roentgen Ray Society
Tubular Adenomas of the Breast
Imaging Findings with Histologic Correlation
Mary Scott Soo1,
Nilima Dash2,
Rex Bentley3,
Lawrence H. Lee4 and
Girija Nathan4
1
Department of Radiology, Duke University Medical Center, Box 3808, Hospital
South, Second Floor, Red Zone, Durham, NC 27710.
2
Department of Diagnostic Radiology, Allegheny General Hospital, 320 E. North
Ave., Pittsburgh, PA 15212
3
Department of Pathology, Duke University Medical Center, Box 3712, Durham, NC
27710.
4
Department of Pathology, Allegheny General Hospital, Pittsburgh, PA
15212.
Received June 30, 1999;
accepted after revision August 9, 1999.
Presented at the annual meeting of the American Roentgen Ray Society, New
Orleans, May 1999.
Address correspondence to M. S. Soo.
Abstract
OBJECTIVE. The purpose of this study is to describe the imaging
features of tubular adenomas, which are rare benign breast tumors usually
found in women younger than 35 years old.
CONCLUSION. In young women, tubular adenomas can look like
noncalcified fibroadenomas on mammography and sonography. In older women,
tubular adenomas may resemble malignant masses with microcalcifications.
Awareness of these findings may help in assessing concordance between imaging
and histologic findings after percutaneous core biopsy of these rare
lesions.
Introduction
Tubular adenomas, also termed pure adenomas, are rare benign tumors of the
breast often found in young women
[1,2,3,4].
Grossly, tubular adenomas appear as circumscribed masses. Microscopically,
they contain closely approximated tubular structures that vary little in size.
Although they are related to fibroadenomas, tubular adenomas differ in that
they have only scanty connective tissue and that the epithelial component
consists of acinar units rather than large ducts. To our knowledge, previous
descriptions of tubular adenomas in the pathology literature have not
mentioned the presence of associated microcalcifications, and the imaging
features of tubular adenomas have not been reported
[1,2,3,4].
The purpose of this study is to describe the imaging features of this benign
lesion, which appear similar to those of either noncalcified fibroadenomas or
malignant masses associated with clusters of microcalcifications on
mammography.
Materials and Methods
Between February 1990 and September 1998, 17 tubular adenomas in 16
patients were identified from pathology databases of two institutions.
Patients ranged in age from 15 to 65 years (mean, 31 years). Twelve of the
tubular adenomas in 11 patients were imaged before histologic sampling; nine
mammograms (Mammomat II and Mammomat III, Siemens, Iselin, NJ; or M-IV, Lorad,
Danbury, CT) and seven sonograms (Performa, Acoustic Imaging/Dornier, Phoenix,
AZ; or Sonoline Elegra, Siemens, Issaquah, WA) were obtained using 7.5- and
10-MHz transducers. These patients constituted the study population. Five
lesions were detected initially on screening mammography and seven presented
as a palpable mass on physical examination. The mammograms, sonograms, and
specimen radiographs available for each lesion were reviewed by two
radiologists experienced in breast imaging. Each mammographic lesion was
characterized according to size, mass characteristics, morphology, and
distribution of microcalcifications. Sonographic images were reviewed, with
lesions classified according to the criteria established by Stavros et al.
[5]. Nine lesions were
surgically excised, and three were histologically sampled by imaging-guided
percutaneous core biopsy using a 14-gauge needle either sonographically
(Performa, Acoustic Imaging/Dornier; or Sonoline Elegra, Siemens) or
stereotactically (Mammotest; Fischer Imaging, Denver, CO). Mammographic and
sonographic findings were then correlated with histology.
Results
The imaging appearance of the tubular adenomas was divided into two main
categories. The first group consisted of eight noncalcified solid masses in
seven patients (age range, 15-47 years; mean age, 29 years). Seven of the
eight lesions were palpable, although one was identified on physical
examination only in retrospect after detection on a screening mammogram. The
second group included mammographically detected ill-defined masses with
associated microcalcifications in three patients (age range, 38-65 years; mean
patient age, 45 years). In one patient, an incidental small noncalcified
tubular adenoma with no mammographic correlate was seen histologically within
a fibrocystic region identified after surgical excision of a cluster of
suspicious microcalcifications spanning a 3-cm area.
Of the group of eight noncalcified masses, mammograms of four showed
circumscribed oval masses (Fig.
1A) or lobulated obscured masses ranging in size from 13 to 23 mm
(mean, 16.75 mm). Two masses were not visible in a mammographically dense
breast. Sonograms of the noncalcified masses showed six with discrete
well-circumscribed oval or lobulated solid masses (Figs.
1B and
2A), five with enhanced sound
transmission, and one with sound transmission equal to that of the surrounding
tissue. Each mass was ellipsoid and mildly hypoechoic with a homogeneous
echotexture. Two masses had an echogenic pseudocapsule. None of the lesions
had malignant features based on the criteria established by Stavros et al.
[5]. Tissue sampling of each
lesion was performed because the lesions were newly palpable or had enlarged
since previous mammographic examination.
View larger version (72K):
[in this window]
[in a new window]
[as a PowerPoint slide]
|
Fig. 1A. —39-year-old woman with palpable tubular adenoma in right breast.
Mediolateral oblique mammogram shows mostly circumscribed mass
(arrows) overlying pectoralis muscle adjacent to cutaneous marker. No
microcalcifications were seen on mammography.
|
|
View larger version (130K):
[in this window]
[in a new window]
[as a PowerPoint slide]
|
Fig. 1B. —39-year-old woman with palpable tubular adenoma in right breast.
Sonogram of tubular adenoma shows circumscribed homogeneous hypoechoic oval
mass (cursors) without posterior acoustic shadowing or
microcalcifications.
|
|
In the group of three calcified masses, lesions ranged in size from 5 to 25
mm. Each mass was partly obscured in a mammographically dense breast and
contained tightly clustered microcalcifications (Figs.
3A,3B,3C,3D
and 4). In all three masses,
the clusters of microcalcifications were quite similar to one another in
appearance (Figs.
3A,3B,3C,3D,4,5).
Individually, the microcalcifications measured 0.6 mm or less and were round,
punctate, or irregular in shape. The density of the microcalcifications was
relatively high for their small size. In each lesion, a large number of
microcalcifications were clustered in a small area. Although each lesion was
initially considered suspicious for malignancy (Breast Imaging Reporting and
Data System category 4 [6]), no
linear, branching, or castlike calcifications that would suggest high-grade
ductal carcinoma in situ were identified. In addition, no coarse, benign
popcorn-like calcifications (often seen in degenerated fibroadenomas) were
identified in these related lesions.
View larger version (129K):
[in this window]
[in a new window]
[as a PowerPoint slide]
|
Fig. 3A. —38-year-old woman with calcified tubular adenoma in right breast.
Right craniocaudal mammogram shows obscured mass (arrows) containing
numerous tiny punctate and irregular microcalcifications.
|
|
View larger version (102K):
[in this window]
[in a new window]
[as a PowerPoint slide]
|
Fig. 3B. —38-year-old woman with calcified tubular adenoma in right breast.
True lateral spot-compression magnification mammogram shows
microcalcifications to be tightly clustered and relatively dense for small
size.
|
|
View larger version (132K):
[in this window]
[in a new window]
[as a PowerPoint slide]
|
Fig. 3C. —38-year-old woman with calcified tubular adenoma in right breast.
Sonogram of tubular adenoma shows heterogeneous ill-defined hypoechoic mass
(arrows) with multiple central echogenic foci, representing
microcalcifications.
|
|
View larger version (181K):
[in this window]
[in a new window]
[as a PowerPoint slide]
|
Fig. 3D. —38-year-old woman with calcified tubular adenoma in right breast.
Photomicrograph of tubular adenoma shows dilated acinus (arrows) with
internal microcalcifications. Note numerous smaller acini in surrounding
area.
|
|
View larger version (141K):
[in this window]
[in a new window]
[as a PowerPoint slide]
|
Fig. 4. —39-year-old woman with tubular adenoma in right breast. Craniocaudal
mammogram shows ill-defined mass (arrows) with numerous internal
microcalcifications. Microcalcifications are tightly clustered, punctate, and
irregular in shape, similar to those seen in Figure
3A,3B,3C,3D.
|
|
View larger version (121K):
[in this window]
[in a new window]
[as a PowerPoint slide]
|
Fig. 5. —59-year-old woman with tubular adenoma of left breast. Specimen
radiograph obtained after excisional biopsy of tubular adenoma shows obscured
oval mass (arrows) with tiny punctate microcalcifications, similar to
those seen in Figures
3A,3B,3C,3D
and 4.
|
|
Sonography of one calcified mass revealed a lobulated heterogeneous mass
with ill-defined margins (Fig.
3C). Numerous echogenic microcalcifications were clearly
identified centrally within this mass. This lesion was categorized as
malignant based on the criteria established by Stavros et al.
[5].
Histologically, the tubular adenomas consisted of closely packed acini with
little supporting stroma (Figs.
2B and
3D). Microcalcifications were
identified in only the three lesions that had microcalcifications on
mammography. These large round calcium-phosphate microcalcifications were
located inside dilated acini (Fig.
3D) and were thought to result from calcification of inspissated
secretions. No calcifications were identified in the scanty supporting
stroma.
View larger version (142K):
[in this window]
[in a new window]
[as a PowerPoint slide]
|
Fig. 2B. —19-year-old woman with palpable tubular adenoma in right breast.
Photomicrograph of tubular adenoma reveals numerous tightly packed acinar
units with sparse intervening connective tissue. Microcalcifications were
absent at histology in this young patient.
|
|
Discussion
Tubular adenomas are rare benign breast tumors that are often found in
young women and are related to fibroadenomas. Histologically, tubular adenomas
are distinguished by their homogeneously tightly packed tubular or acinar
epithelial component and sparse connective tissue
[1,2,3,4].
Fibroadenomas, on the other hand, have abundant stroma and an epithelial
component consisting of large ducts (Fig.
6). Some lesions fall along a spectrum between the histologic
appearance of fibroadenomas and that of tubular adenomas, consisting of mixed
features including areas of tightly packed tubules, areas of more abundant
connective tissue, and dilated ducts. In these lesions, a diagnosis of
fibroadenoma is usually made. The diagnosis of tubular adenoma is usually
reserved for those lesions with purely acinar units and little stroma.
View larger version (111K):
[in this window]
[in a new window]
[as a PowerPoint slide]
|
Fig. 6. —45-year-old woman with typical fibroadenoma. Photomicrograph shows
mass (arrows) is composed predominantly of connective tissue and
contains only scattered large dilated ducts, unlike the numerous and tightly
packed acinar units and sparse connective tissue of tubular adenomas seen in
Figures
2A,2B
and
3A,3B,3C,3D.
|
|
Microcalcifications have not, to our knowledge, been previously described
within benign tubular adenomas in the pathology literature
[1,2,3,4].
Most of these reports were published in the early 1980s before the widespread
use of screening mammography. Currently, the identification of
microcalcifications in pathology specimens from mammographically detected
clusters of microcalcifications is critical to ensure that the correct region
was sampled.
The imaging appearance of tubular adenomas of the breast has not, to our
knowledge, been previously described. In our series, three of the five
screening-detected lesions contained microcalcifications and all occurred in
patients who were 38 years old or older. In these patients,
microcalcifications forming in inspissated secretions were located within the
dilated acinar glands. It is uncertain whether the presence of calcifications
in this group of relatively older patients relates to increased patient age,
the amount of secretions in the tubules, or other factors. The
microcalcifications seen mammographically were initially considered suspicious
for malignancy, yet their appearance was similar in each. The pattern of
dense, punctate, or irregular microcalcifications without castlike or
branching forms that are tightly grouped within a mass may prove to be a
distinctive feature of tubular adenomas. Currently, however, biopsy of these
lesions is still necessary to exclude a malignant process. Noncalcified
tubular adenomas presented in a relatively younger group of patients and were
seen mammographically and sonographically as masses similar to fibroadenomas.
There was no histologic evidence of microcalcifications within the lesions
presenting as noncalcified masses on mammography and sonography. Most of these
lesions (75%) were detected as enlarging masses on physical examination.
In conclusion, tubular adenomas may present in younger women
mammographically and sonographically as masses similar in appearance to
noncalcified fibroadenomas. They also can present as masses with numerous
tightly packed punctate and irregular microcalcifications; the distinctive
appearance of these microcalcifications should raise the possibility of the
diagnosis of tubular adenoma. Although biopsy of lesions with these imaging
findings is still necessary to exclude a malignant process, the histologic
diagnosis of tubular adenoma would be an acceptable diagnosis after needle
core biopsy. Awareness of these findings may aid in determining concordance
between imaging and histologic findings after percutaneous core biopsy of
these rare lesions.
References
-
Moross T, Lang AP, Mahoney L. Tubular adenoma of breast.
Arch Pathol Lab Med
1983;107:84-86[Medline]
-
Bhargava S, Sant M, Arora MM. Tubular and lactating adenomas of
breast. Indian J Pathol Microbiol
1981;24:221-227[Medline]
-
O'Hara MF, Page DL. Adenomas of the breast and ectopic breast under
lactational influences. Hum Pathol
1985;16:707-712[Medline]
-
Hansen CP, Fahrenkrugh L, Hastrup N. Tubular adenoma of the breast
in a pregnant girl: report on a case. Eur J Pediatr Surg
1991;1:364-365[Medline]
-
Stavros TA, Thickman D, Rapp CL, Dennis MA, Parker SH, Sisney GA.
Solid breast nodules: use of sonography to distinguish between benign and
malignant lesions. Radiology
1995;196:123-134[Abstract/Free Full Text]
-
American College of Radiology. Breast imaging reporting and
data system, 3rd ed. Reston, VA: American College of Radiology,
1998
CiteULike 
Complore 
Connotea 
Del.icio.us 
Digg 
Reddit 
Technorati What's this?
This article has been cited by other articles:
|
|
|
|
 
A. Irshad, S. J. Ackerman, T. L. Pope, C. K. Moses, T. Rumboldt, and B. Panzegrau
Rare Breast Lesions: Correlation of Imaging and Histologic Features with WHO Classification
RadioGraphics,
September 1, 2008;
28(5):
1399 - 1414.
[Abstract]
[Full Text]
[PDF]
|
|
|
|
|
|
|
M. Guray and A. A. Sahin
Benign breast diseases: classification, diagnosis, and management.
Oncologist,
May 1, 2006;
11(5):
435 - 449.
[Abstract]
[Full Text]
[PDF]
|
|
|
|
|
|
|
R. Katz-Brull, P. T. Lavin, and R. E. Lenkinski
Clinical Utility of Proton Magnetic Resonance Spectroscopy in Characterizing Breast Lesions
J Natl Cancer Inst,
August 21, 2002;
94(16):
1197 - 1203.
[Abstract]
[Full Text]
[PDF]
|
|
|
Top
Abstract
Introduction
