"If anything, we have information overload with respect to breast
This surfeit of information is nearly matched by the number of
techniques used to obtain breast cells and tissue. New technologies
are being developed daily (or so it seems). There’s ductal lavage
and nipple aspiration; core-needle biopsy and fine needle aspiration;
random FNA and needle localization excisional biopsy.
As with certain other human endeavors, however, technique will
take you only so far. No matter how expert the moves, at some point
they must be meaningful. Certain words must be said, certain phrases
must be uttered.
In the case of breast specimen workup, what one longs to hear
is: What subset of patients will benefit?
The answer lies not in blind obeisance to one method. No latest-and-greatest
blesses the field, and abandoning one technique in favor of another
seems ill-advised at best, foolish at worst. Each technique has
its uses, and all have limitations as well as plenty to recommend
"No single procedure is good for everyone," says Shahla Masood,
On the other hand, nearly every patient can benefit from at least one method.
By parsing the techniques, a modus vivendi does emerge. It’s not so much a matter
of finding a middle ground; rather, it’s to find the best foothold for each
The "fine" in fine-needle aspiration "is not a mark of quality,
but of the size of the needle," jokes Dr. Silverberg. Wordplay aside,
he and others acknowledge that FNA remains a useful tool, despite
the apparent shift toward core-needle biopsies in recent years.
It’s less traumatic than core biopsy.
That being said, it’s important to take aim at the right type
of lesion. Think palpable lesions. "Particularly in palpable lesions,
fine-needle aspiration should be used as the initial approach,"
says Dr. Masood, who is professor and associate chair of the Department
of Pathology at the University of Florida and chief of pathology
and laboratory service and director of the breast center at the
UF Health Science Center/Shands, Jacksonville.
Helen H. Wang, MD, DrPH, seconds that notion. "If there is a
lesion that can be palpated by physical exam, it’s very easy to
do a fine-needle aspiration first," says Dr. Wang, associate professor
of pathology, Harvard Medical School, and director of cytopathology,
Beth Israel Deaconess Medical Center, Boston. "You don’t lose
anything, and you can get a diagnosis very quickly." Indeed, if
a direct smear is made, the pathologist can offer a bedside interpretation.
And while some detractors "talk about epithelial misplacement,"
says Dr. Wang, "you rarely compromise the lesion. Maybe a little
FNA is appropriate "if it’s a superficial tumor, if it is obviously
benign, if it is obviously malignant," says Syed A. Hoda, MD.
"Then the fine-needle aspiration can confirm the impression very
quickly." FNA is also the best choice for patients who continue
to present with huge tumors, many of which are considered to be
inoperable. A quick FNA can make the call, enabling patients to
start chemotherapy immediately. "But those cases are very rare,
at least in our setting," says Dr. Hoda, associate professor of
pathology, New York-Presbyterian Hospital, Weill Cornell Medical
College of Cornell University.
Because FNA is minimally invasive, patients tolerate the procedure
well. "It’s very atraumatic," Dr. Masood notes. Unlike core biopsy,
it does not produce scarring or hemorrhaging, nor does it interfere
with subsequent mammographic interpretation. FNA may also be preferable
for sampling some nonpalpable lesions that are evident on ultrasound,
she suggests, to reduce patient trauma and discomfort.
FNA is cheaper to do than core biopsies, hands down. As Dr.
Wang puts it: "The core biopsy gun is a lot more expensive than
a syringe and a needle."
In short, "If we can get a diagnosis with a simple, pretty noninvasive procedure,
with minimal cost, then that’s wonderful," says Dr. Wang. "If that is not
possible, then we move on to core biopsy."
In some quarters, that shift is coming preemptively.
"It depends on who you are talking to," says Dr. Wang. The number
of breast core-needle biopsies has surged in recent years, she
says, unlike breast FNAs. "But some labs do show an increase [in
FNAs], especially for the
Others report a marked decrease. Dr. Hoda recalls that 10 years
ago, during his cytology fellowship, "almost every lesion used
to be aspirated. Now, I think only about 25 percent of them are."
"The core biopsies are taking over," says Yolanda C. Oertel,
MD. She sees it in her own practice, as director of the fine-needle
aspiration service at Washington (D.C.) Hospital Center. "Breast
aspirates used to be the most common aspirate in my practice,
until about 1984. Then thyroid took over, and breast aspirates
A similar shift occurred in prostate cancer, she notes. "Years
ago, we used to do quite a few prostatic aspirates, and then core
biopsy took over. So I am afraid that breast aspirates are going
to go the way of the prostatic aspirate."
The reasons for FNA’s dwindling fortunes? Take your pick.
Though FNA is cheaper, "Cost doesn’t seem to be a primary concern
in this country," says Dr. Wang—or at least not when the
threat of legal action comes knocking. In medical malpractice,
cases of missed carcinoma are "so expensive, people will do anything
to avoid it," Dr. Wang says. "We want to make absolutely sure
that we don’t miss a carcinoma, and so people go the full length
to make sure we don’t." In that scenario, the more-expensive core
biopsy procedure becomes attractive because it provides more material,
permits more ancillary studies, and does not require cytology
training to interpret it.
Lamenting the move away from FNA, Dr. Masood places part of
the blame for its decline on pathologists. "They don’t want to
take the time to work through the challenges of interpreting FNA
FNA is a deceptively simple technique, observes Dr. Oertel,
which also works against it. "Many people, particularly surgeons,
think it’s just a matter of sticking a needle in. It’s not." This
has led to a too-high rate of unsatisfactory specimens, which
further dampens interest in FNA. "We need to be mastering the
technique and teaching surgeons how to do it better," Dr. Oertel
says. Otherwise, she says, "Surgeons get disgusted with it, and
they send the patient, even for palpable lesions, for a core biopsy."
It goes without saying that those who don’t perform the technique
won’t get better at it.
This catch-22 traps pathologists as well. "This is not something
that someone can interpret if he or she does only a few specimens
a month," says Dr. Wang. "It requires experience." It also requires
precise understanding between those who render the cytology report
and those who receive it. "This is extremely important when we
are dealing with small specimens," she says. "People have to set
their expectations accordingly—that there are limitations
in interpretation because of the very small amount of material.
"They also have to understand there are overlapping features
between benign and malignant lesions of the breast," she continues.
"Certain malignant lesions can look very, very banal, and there
are certain benign lesions that can look quite atypical. The clinician
and the pathologist need to have the same understanding of the
words and categories we use in
With breast tumor size shrinking, FNA loses out a little more. Fifty years
ago, women diagnosed with breast cancer had tumors the size of a small lemon,
says Dr. Hoda. "But now, at least in our practice, the average tumor measures
less than 2 cm. And with smaller lesions, the less you manipulate them, the
better. So it’s best to get the diagnosis in one shot." Using core biopsy
initially "reduces many steps in the diagnosis," he says.
FNA does have its limitations, a point readily conceded
FNA cannot distinguish between in situ lesions and invasive
carcinoma. "That is a problem, especially for small or nonpalpable
lesions," acknowledges Dr. Wang.
Indeed, that’s the main problem with FNA, says Dr. Silverberg.
On the other hand, he says, "In instances where clinically it’s
obviously invasive, just knowing that it’s cancer is enough information
to go on to plan treatment." Similarly, in a patient who has had
breast cancer who presents with a new mass elsewhere—lymph
node, skin, liver—simply obtaining malignant cells by FNA
is sufficient to confirm metastatic disease. "So there are situations
where FNA will probably do just as good a job as a core, and could
be preferred because of the relative ease and economy," he says.
There are other chinks in FNA’s armor. Some of FNA’s weaknesses
lie coiled within its strengths. Though using a fine needle minimizes
trauma, it also means less material for ancillary studies, such
as estrogen receptor/progesterone receptor and HER2/neu. That’s
hardly a small consideration, especially for patients interested
in preoperative adjuvant therapy. "We can probably get enough
to do one additional study," Dr. Wang says. More than that would
be difficult. "You’re talking about many passes," she says.
Dr. Oertel notes that lobular carcinoma is difficult to diagnose
on aspirates. "The cells tend to be fewer and smaller, and many
times you don’t get tumor cellularity," she explains.
But despite breast FNA’s limitations, and with firsthand knowledge
of its declining use—80 percent of the aspirates she performs
now are on thyroid—Dr. Oertel sees no reason to write off
FNA. "Oh, absolutely not," she says.
"I hope breast FNA can hold its place," adds Dr. Wang.
It will have to make room for core-needle biopsy, however.
Core biopsy has its advantages, and can be used to fill in some
of the gaps FNA fails to fill. To wit:
It can be used to assess microcalcifications in the absence of
Core-needle biopsy, like FNA, has suffered its share of bad
press over the years. "One misunderstanding is that you can’t
do ER and PR on core biopsy," says Dr. Hoda. "You can do it—we
do it all the time." This misperception arose early on, when immunostaining
techniques were less refined. "Now it can be easily done," he
says. Performing HER2/neu immunohistochemistry studies on core
biopsy material remains problematic, though, due to the considerable
edge artifact present on the long, narrow specimens. "But if you
were to employ FISH, it could easily be resolved on core biopsy
material," Dr. Hoda says.
Others mistakenly assert core biopsy promotes tumor metastases,
assuming that the greater degree of manipulation involved in the
technique "feeds" the blood vessels. "But it has not been proven
to be the case," says Dr. Hoda. However, repeated core biopsy—and
repeated FNA, for that matter—can dislodge tumor and adjacent
But core needle does not slip easily into the one-size-fits-all
model, any more than FNA does. As with FNA, physicians need to
understand the limitations of core-needle biopsy, says Dr. Masood.
"We do not want to fall into the trap of false security with core-needle
biopsy," she says.
Core biopsy cannot always distinguish in situ lesions from invasive
carcinoma, says Dr. Wang, although it’s much better at doing so
than FNA. And core biopsy has a greater risk of producing artifact,
such as epithelial misplacement.
Less common, but a risk nonetheless, is what could be termed
"disappearing lesions." Explains Dr. Wang: "There are cases where
the lesion is so small, they can no longer find it after the core
biopsy. You can’t estimate the size of the lesion using core,
and when the lesion is small, the core can remove the carcinoma
completely. I haven’t heard of that happening with fine-needle
Core-needle biopsy fails to diagnose a handful of other lesions,
Dr. Masood says. Among them: papillary lesions, atypical hyperplasia,
lobular lesions, fibroepithelial lesions, and radial scars. "The
majority of these lesions need to be followed by a needle localization
excisional biopsy," she says.
Overcalling tumors is another pitfall of core biopsy. Radial
scar and sclerosing adenosis are the worst culprits, according
to Dr. Hoda.
And, finally, comes this warning. "What you don’t want is to
put together a package of doing every technique and seeing what
works," says Dr. Masood. "I don’t approve of that approach at
Says Dr. Hoda: "Doing FNA, followed immediately by a core without waiting
for the results of the former, is double-dipping, and it’s probably abusive
of both procedures."
The story could end there. FNA will probably not evolve
technically, at least not with any great strides. The aim, after
all, is to use a very small needle. "That’s the beauty of it,"
says Dr. Wang. "It’s meant to be a minimally invasive test; it’s
not meant to become a complicated and complex technique."
Core-needle biopsy has more potential for technical improvement,
and has already benefited from several technical advances over
the years. The gauge of the needles has gradually increased, moving
from, typically, a 22-gauge needle to a 14- or even 11-gauge needle,
providing wider specimens. Vacuum-assisted techniques mean biopsies
can be done more quickly, and with more cores. "It’s becoming
easier for the pathologist to see the tissue better and make a
diagnosis," says Dr. Silverberg.
There are limits, of course. Dr. Hoda describes a core-needle
technique called ABBI (advanced breast biopsy instrument), which
"has a needle that’s as large as a cigar, if you can believe it,"
he says. The idea is to combine diagnosis and treatment in one
modality. "But it has not found application, at least not in the
United States," says Dr. Hoda, whose colleagues at Cornell abandoned
the procedure after only a few attempts. "It was very uncomfortable,
it had complications, and invariably they had to go back and dig
out more tissue," he says. "ABBI was, I think, before its time."
Pushed by breakthroughs in other areas, however, both FNA and
core-needle biopsy may find their horizons expanding.
In core biopsy, the impetus could come from a technique called
radioablation, which uses heat to destroy tumors. This has been
used for years to ablate metastatic tumors, predominantly in the
liver. Because of its success, it is now being looked at, with
a rather hopeful eye, to treat primary tumors, in the breast as
well as in prostate, brain, and lung.
Rache M. Simmons, MD, associate professor of surgery, New York-Presbyterian
Hospital, Weill Cornell Medical College of Cornell University,
is exploring this technique as part of a tri-institutional trial
at Cornell, MD Anderson Cancer Center, and John Wayne Cancer Institute.
The researchers are looking at primary tumors 2 cm or less in
diameter, located 1 cm or more from the skin and from underlying
breast muscle. Guided by ultrasound, surgeons insert a probe that
contains wires, which are then extruded into the tumor. The wires
create a frictional heat, which destroys the cancer. (Heat is
only one of several intriguing possibilities, notes Dr. Simmons;
other researchers are assessing whether freezing, cryoablation,
or lasers can be used to destroy tumor without resorting to surgery.)
Currently, the researchers are following an ablate-and-resect
protocol. "Once we have the tumor out, we’re looking at how effective
the probe was in actually destroying the cancer," Dr. Simmons
says. "In addition to the gross analysis and the H&E analysis,
we’re also doing an NADH stain, looking for tissue viability."
So far, she says, "The results have been good, not fantastic."
"Certainly the tissue you ablate is destroyed," she says. "There’s
no question about that. The issue is making sure that you’re actually
Patients who receive neoadjuvant chemotherapy have posed a challenge.
In a couple of these patients, the tumor shrunk to a patchwork
of little pockets around the breast, rather than concentrically.
"What happened was that one tumor ball was seen sonographically,
and that was successfully ablated. But when they did the resection,
they found other little pockets that weren’t detectable by imaging—and
of course, they weren’t ablated," Dr. Simmons says.
In several other cases, the tumors were actually larger than
they appeared to be on imaging; in another patient, what appeared
to be tumor wasn’t. "What we ablated was destroyed, but it wasn’t
the cancer," Dr. Simmons says.
Cautioning that the data are early, Dr. Simmons says, "This
works well in killing cancer; the limitation is being able to
say with confidence, ’This is all the tumor that there is.’ "
"It’s not a matter of improving the technique," she says. "It’s
a matter of selecting out the appropriate patients for whom it
will be successful." Adding MRI and PET scans to the currently
used methods of ultrasound and mammogram may help physicians do
That, in turn, could open the door for more core biopsies.
"You have to use core biopsies, because when you ablate the tumor, you lose
the ability to get the ER, PR, and HER2/neu," Dr. Simmons says. "You also
want to confirm that it is indeed cancer." Furthermore, she says, "If we ever
move to an ablate-and-not-resect protocol, we may want to do cores after we’ve
done the ablation, to see if there’s residual tumor."
FNA could also see expanded use—in risk assessment.
But first, a detour through nipple aspiration and ductal lavage.
Ductal lavage is not a diagnostic technique; it’s a tool for
assessing the level of risk for developing breast cancer in those
who already fall into the "high risk" category.
Nor is ductal lavage a screening technique for the general population.
However, the high-risk category alone comprises a "pretty significant
population, because breast cancer is such a common disease," says
Britt-Marie Ljung, MD.
The technique is an offshoot of nipple aspiration, which, up
to now, has been used primarily as an investigative tool. "Nipple
aspirations have been around for a long time," says Dr. Ljung,
professor of pathology at the University of California in San
Francisco. "Ductal lavage has really been built on nipple aspiration
data," which show that women with abnormal cytology in nipple
aspirates of breast fluid have an increased risk of breast cancer
(Wrensch MR, et al. J Natl Cancer Inst. 2001;93: 1791-1798).
The problem is that the nipple aspiration samples—obtained
via a small suction device placed on the nipple—are quite
small. "You can’t do very much with it, and the material you get
frequently does not contain the epithelial cells," says Dr. Ljung.
Moreover, not everyone produces nipple aspiration fluid, although
there is some indication that those who don’t produce fluid have
a significantly lower risk of developing breast cancer. (On the
other hand, just to give you an idea of how complicated this all
is, women who’ve never had children—a risk factor for breast
cancer—do not readily produce ductal lavage fluid.)
Ductal lavage can produce much more diagnostic material. In
a recently published study that Dr. Ljung participated in (Dooley
WC, et al. J Natl Cancer Inst. 2001;93:1624-1632), which
looked at high-risk women, the median number of epithelial cells
collected by nipple aspiration was 120 per breast, versus 13,500
per duct using ductal lavage. "I think there is significant possibility
that we’ll be able to do a number of molecular studies on these
specimens and more precisely pin down which patients are truly
at the highest risk of developing cancer," says Dr. Ljung. "It’s
also possible we can use ductal lavage to monitor patients on
prophylactic treatment, such as tamoxifen, or possibly even to
introduce treatment through this
The first step in ductal lavage is to produce nipple aspirate
fluid—the droplets emerging on the surface indicate duct
openings. Not all duct openings in a given nipple will produce
fluid, though in patients with increased risk for breast cancer,
80 to 90 percent will produce fluid from at least one duct, says
Dr. Ljung. A catheter is then inserted into the open duct to introduce
saline, 2 to 4 mLs at a time. This is repeated until 10 to 20
mLs have been washed through the system.
The cells that are retrieved from the duct linings can be prepared
in any number of ways, ranging from Millipore filters to Cytospin
to ThinPrep or AutoCyte Prep. Many give high marks to the liquid-based
So far, so good.
"People generally have no problem identifying straightforward
normal specimens—benign and malignant," says Dr. Ljung,
who along with retired pathologist Eileen B. King, MD, developed
the cytologic criteria for examining ductal lavage specimens;
she also reviewed specimens as part of a Web-based training program
run by the manufacturer of a ductal lavage device. (The company,
Pro-Duct Health, was acquired by Cytyc Corp. late last year.)
"When there is an abnormality, they tend to overinterpret a little
bit—what they call ’marked changes’ we would downgrade to
’mild changes,’" she says. "And there are some cases where they
call it ’mild changes,’ and there isn’t really anything."
Mild changes most likely represent a benign proliferative process
of some sort, she says. "It’s not totally normal, but it’s nothing
approaching carcinoma in situ." Benign papillary processes, such
as papillomas and papillomatosis, account for a fairly large chunk
of that category. "As we get more experience with these types
of lesions, the features are actually quite specific," she says.
Furthermore, there are data in the literature indicating papillary
proliferations are associated with an increased risk of developing
breast cancer. "So this is a meaningful finding in these specimens."
Marked changes are more severe, of course. "In that category, I would have
significant concern about a neoplastic process going on," says Dr. Ljung.
"But there aren’t enough features to make a definitive diagnosis." In a very
small subset of patients, she adds, frank carcinoma can be seen in the specimens.
But the "main purpose of the procedure is to risk stratify and find early
changes before frank carcinoma is present," she says.
Now for the limitations.
"The problem with ductal lavage is that it’s new," says Seema
A. Khan, MD, SM, associate professor of surgery, Northwestern
Memorial Hospital, Northwestern University, Chicago. "Which, of
course, is not a problem in and of itself, but as with anything
new, we don’t have sufficient information to define where it fits
Dr. Khan, who participated in the Dooley study, says it’s reasonable
to assume that the presence of abnormal cells retrieved by ductal
lavage is an indicator of breast cancer risk. The next leap of
logic—that the procedure can be used to detect breast cancer
early in women who have normal physical exams and normal mammograms—is
not clear-cut. "That’s because we don’t know the accuracy of these
findings of atypical cells, in terms of being able to identify
a real abnormality in the breast," she says.
One of the problems is the branches of the ductal system can
occupy a fairly large volume of breast tissue. Within that large
volume, physicians would need to localize the lesion producing
the atypical lavage cells. "That has not been established yet,"
says Dr. Khan. "And we would need to do that before we can start
assuming that finding abnormal cells by ductal lavage is a method
of early cancer detection." MRI, ductograms, ductoscopy, or injected
dye may provide means to do this, says Dr. Ljung, and all are
being looked at.
Also yet to be determined: the correlation between ductal lavage
cytology findings and histopathology findings in patients undergoing
Ritu Nayar, MD, MIAC, who works with Dr. Khan and is director
of cytopathology at Northwestern, raises practical issues related
to handling ductal lavage samples.
It’s important to prevent air drying artifact, she says, which
can interfere with interpretation, and maximize cell yield. And
she echoes Dr. Ljung in cautioning against overcalling degenerative
or reactive changes as atypia. In addition, she says, "Subjective
differences in morphologic criteria and interpretation occur,
and, at times, even intraobserver variability exists. It definitely
helps to take the Web-based training and get a secondary review
when starting to interpret these samples."
In women being lavaged for risk assessment, who do not present
with clinical abnormalities, "Wet ducts often give a lot of histiocytes
and/or few to no epithelial cells," she says. "This may indicate
that wet ducts are often benign. However, we have picked up some
significant disease, including high-grade DCIS, during risk assessment
by this procedure."
Using ductal lavage for breast cancer risk assessment is based
on the fact that atypia increases that risk, Dr. Nayar notes.
But, she says, "We do not know if mild atypia can be equated to
histologic ADH/low-grade DCIS. Equating marked atypia to ADH/DCIS
is likely to be more reliable, but we need more followup studies
to be sure." Northwestern, she says, is involved in cytology-histology
correlation studies in women with radiologic or pathologic, or
Nonetheless, says Dr. Ljung and others, "Ductal lavage is already clinically
a useful test in a subset of patients." Patients with a Gail index of 1.7,
who are considering tamoxifen treatment, "don’t have a lot of information
to go on," she says. "And it’s not like tamoxifen is a no-brainer—there
are plenty of side effects." Undergoing ductal lavage and finding abnormal
cells, whether mild or marked, can improve the precision of risk estimation,
giving these high-risk women information that will help them decide about
With the fortunes of ductal lavage apparently on the
rise, nipple aspiration cytology might be expected to remain on
the back burner as little more than an investigational tool, despite
the strength of the data presented by Dr. Wrensch and her fellow
Not so fast.
As it turns out, nipple aspiration fluid is extremely rich in
protein, says Carol Fabian, MD, director of the breast cancer
prevention center and professor of medicine at the University
of Kansas Medical Center. And levels of estradiol, testosterone,
and several other hormones are 10 to 15 times higher in nipple
aspirate fluid than in serum.
Aromatase inhibitors "have recently been shown to be superior
to tamoxifen as an adjuvant therapy for breast cancer," she says.
"So what we are looking at is trying to determine whether we can
see a response to these inhibitors in the prevention setting by
measuring change in epithelial cell proliferation—obtained
from FNA—as well as nipple aspirate fluid hormone levels."
This is one of several breast cancer prevention studies being
conducted at the University of Kansas Medical Center. Additional
upcoming trials include a multicenter National Cancer Institute-sponsored
study to compare ductal lavage specimens with FNA.
Random periareolar FNA, to be specific. Unlike FNA done for
diagnostic purposes, random FNA is used as a risk assessment tool.
Explains Dr. Fabian: "About 12 years ago, we wanted to randomly
sample breast tissue in high-risk women, with the idea that if
the patient had widespread precancerous lesions in her breast,
then we would be likely to observe these precancerous changes
in the specimen by random periareolar FNA." The technique is not
as random as it sounds—most of the terminal lobular duct
units where breast cancers are thought to arise appear to be concentrated
behind the nipple areolar area and in the upper outer quadrant.
In a study published in the Journal of the National Cancer
Institute (Fabian CJ, et al. 2000;92:1217-1227), Dr. Fabian
and colleagues performed random FNAs in 480 high-risk women, then
followed them for development of breast cancer. "Finding atypical
hyperplasia on random fine-needle aspiration was an extremely
strong predictor for short-term risk for breast cancer," she says.
Median followup was four years.
Their research has led to several NCI-sponsored chemoprevention
trials, including the aforementioned study to compare ductal lavage
and random FNA as possible methods for performing chemoprevention
studies—in this case, celecoxib, an anti-inflammatory drug
that may be useful against estrogen receptor-negative precancerous
Random periareolar FNA will be the method used to provide cells
for the primary endpoint in this study, as it has in their previous
studies, says Dr. Fabian. "We know we can get cells at both baseline
and at the end of the study with FNA, but no one knows if that
can be done with ductal lavage." Her suspicion is that, although
nipple aspirate fluid (which serves as the guide for lavage) can
be obtained after 12 months of celecoxib, it may not be possible
with antihormonal agents, which lower the level of estrogen or
block estrogen receptor transcription in the breast tissue.
The FNA samples, though small, produce enough material to do
cytology and several immunocytochemical biomarker studies, Dr.
Fabian reports. "Remember, we’re aspirating both breasts, at two
different sites, so there’s much more material than there usually
is with a traditional diagnostic fine-needle aspiration." Interestingly,
immunohistochemistry studies have not yet been done on ductal
lavage specimens, though she and her colleagues are looking into
it in preparation for the study.
It is too early to predict the path for many of these possible
applications. Looking into the future, most offer only one solid
prediction—that no one technique will outshine the rest.
Each one will serve to complement, not replace, the others.
"It’s not as if we’re replacing methods that work particularly
well," says Dr. Ljung. Despite the breakthroughs, despite the
information overload, despite the winds of change, "There’s still
a big vacuum that we’re trying to fill."
Karen Titus is CAP TODAY contributing editor and co-managing editor.