Clinical Breast Problems and Unusual Breast Conditions

The Male Breast: Gynecomastia and Male Breast Cancer

The incidence of breast cancer in males is rare, constituting less than 1% of all breast cancers in the United States, so usually the symptoms for which men seek clinical attention are from benign disease. Men commonly present for breast imaging because of unilateral or bilateral breast enlargement, breast pain, or a palpable breast lump. Benign gynecomastia, an abnormal proliferation of benign ducts and supporting tissue that causes breast enlargement or a subareolar mass, with or without associated breast pain, is often the cause of many of these complaints in men.

Broad categories of conditions causing gynecomastia include high serum estrogen levels from endogenous or exogenous sources, low serum testosterone levels, endocrine disorders (hyperthyroidism or hypothyroidism), systemic disorders (cirrhosis, chronic renal failure with maintenance by dialysis, and chronic obstructive pulmonary disease), drug-induced (cimetidine, spironolactone, ergotamine, marijuana, anabolic steroids, and estrogen for prostate cancer), tumors (adrenal carcinoma, testicular tumors, and pituitary adenoma), or idiopathic ( Box 10.1 ). Gynecomastia can occur at any age, but it may be seen in particular in neonates as a result of maternal estrogens circulating to the fetus through the placenta, in healthy adolescent boys 1 year after the onset of puberty because of high estradiol levels, or in older men as a result of decreasing serum testosterone levels.

Breast imaging in men is done in the same fashion as in women. The normal male breast is comprised of scant fatty tissue and a few major breast ducts. On the mammogram, the normal male breast consists of fat without obvious fibroglandular tissue, and the pectoralis muscles are usually larger than in women. In some men, there are faint strands of retroareolar tissue ( Fig. 10.1 ); however, there is never as much tissue as in a woman in the normal male.

Pseudogynecomastia is a fatty proliferation of the breasts without proliferation of glandular tissue that simulates gynecomastia clinically, but unlike true gynecomastia, proliferation of glandular breast tissue does not occur.

In both pseudogynecomastia and in women with Turner syndrome, mammograms consist mostly of fat, similar to the normal male breast ( Fig. 10.2 ).

Under a stimulus producing gynecomastia, ductal proliferation and stromal hyperplasia occurs with occasional ductal multiplication and elongation that produces breast enlargement, which may be reversible in the active phase if the stimulus is removed. If the stimulus persists, irreversible stromal fibrosis and ductal epithelial atrophy develop, and the breast enlargement may decrease but not completely resolve.

On the mammogram, gynecomastia in men is shown as glandular tissue in the subareolar region that is symmetric or asymmetric, unilateral or bilateral ( Table 10.1 ). In a large series by , gynecomastia was unilateral in 45% and bilateral in 55% of 206 cases with mammograms. In the early phases of gynecomastia, the glandular tissue is flamelike, consisting of thin strands of glandular tissue extending from the nipple, like fingers extending posteriorly toward the chest wall ( Fig. 10.3 ). With continued proliferation of breast ducts, the glandular tissue may take on a subareolar triangular nodular shape behind the nipple that can be symmetric ( Figs. 10.4 and 10.5 ) or asymmetric ( Fig. 10.6 ). When gynecomastia progresses to its later irreversible, stromal fibrotic phase it may take on the appearance of diffuse dense tissue ( Fig. 10.7 ).

On ultrasound, gynecomastia is hypoechoic and consists of dark flamelike, fingerlike, or triangular structures extending posteriorly toward the chest wall from the nipple (see Figs. 10.3 to 10.7 ). Ultrasound is found to be of limited value when the mammogram clearly shows gynecomastia in symptomatic men but is clearly helpful when the mammogram is abnormal and suggesting cancer.

Male breast cancer accounts for less than 1% of all cancers found in men and is usually diagnosed at or around age 60 years old, which is older than the mean age for the diagnosis of breast cancer in women ( Box 10.2 ). Male breast cancer has the same prognosis as breast cancer in women, but it is often detected at a higher stage than in women because of delay in diagnosis. Up to 50% of men have axillary adenopathy at initial evaluation. Risk factors include Klinefelter syndrome, high estrogen levels such as from prostate cancer treatment, and the development of mumps orchitis at an older age. Male breast cancer is generally manifested as a hard, painless, subareolar mass eccentric to the nipple. When the cancer is not subareolar, cancers in men are usually found in the upper outer quadrant. Clinical symptoms of nipple discharge or ulceration are not rare in association with male breast cancer.

On mammography, male breast cancers are generally dense noncalcified masses in the subareolar region ( Figs. 10.8 and 10.9 ). Calcifications as the only indicator of cancers are less common in men than women, although calcifications may be present ( Figs. 10.10 and 10.11 ). On ultrasound, male breast cancers are usually well circumscribed or irregularly marginated masses. Skin thickening, adenopathy (see Fig. 10.11 ), or skin ulceration are associated with a poor prognosis. Breast cancers in men are usually invasive ductal cancer in 85% of cases, and most of the remaining tumors are medullary, papillary, and intracystic papillary types. An associated component of ductal carcinoma in situ (DCIS) may be present. Invasive lobular carcinoma is rare. Treatment of breast cancer is the same for men as for women and consists of surgery, axillary node dissection, chemotherapy, and radiation therapy for invasive tumors; the prognosis is identical to women undergoing these treatments.

Pregnant and Lactating Patients and Pregnancy-Associated Breast Cancer

Pregnancy produces a proliferation of glandular breast tissue that results in breast enlargement and nodularity in response to female hormones. Fibroadenomas or adenomas of pregnancy respond to pregnancy hormones and may enlarge in this period. Breast masses are difficult to manage in a pregnant patient because surrounding breast nodularity and breast size increases over time. Most masses occurring in pregnancy are benign and include benign lactational adenomas, fibroadenomas, galactoceles, and abscesses ( Box 10.3 ), but the diagnosis of exclusion is pregnancy-associated breast cancer.

Pregnancy-associated breast cancer is defined as breast cancer discovered during pregnancy or within 1 year of delivery ( Box 10.4 ). The incidence of breast cancer in pregnant women is 0.2% to 3.8% of all breast cancers, or 1 in every 3000 to 10,000 pregnancies. Most pregnancy-associated breast cancers are usually invasive ductal cancer, and are usually estrogen receptor negative, similar to nonpregnant, premenopausal women of a similar age. The cancers generally present as a hard mass, but may be associated with bloody nipple discharge or breast edema.

Usually pregnant women are first imaged with breast ultrasound targeted to the area of concern. Pregnant patients often are reluctant to undergo mammography because they are worried about the effect of radiation on the fetus. If the doctor suspects cancer, and even though the breast tissue is dense from pregnancy, it is important to do the mammogram because it might show spiculated masses or suspicious calcifications. Furthermore, scattered radiation delivered by mammography to the fetus is low, and can be further reduced with lead shielding, with the dose about 0.004 Gy ( ). showed that the breast density is not always dense in pregnant and lactating women and varied from scattered fibroglandular density in pregnant patients to heterogeneously dense or dense in lactating women. In their series, mammography was as useful as it is in nonpregnant women who have clinical signs and symptoms of breast disease. In addition, imaging the breasts can be aided in lactating patients by pumping milk from the breasts before the study, thus reducing the breast density on the mammogram.

Mammography showed pregnancy-associated breast cancer in 78% of 23 pregnant women ( ) and in 86% of 15 cases ( ), as masses, pleomorphic calcifications, both masses and calcifications, asymmetries, and breast edema, or were negative because of dense breast tissue. Axillary lymphadenopathy, asymmetries, and skin or trabecular thickening were either primary findings or were associated findings of cancer. In both series, ultrasound was positive in all cases in which it was performed, usually showing irregular solid masses with irregular margins. In the series by , four masses also contained complex echo patterns or cystic components, and most showed acoustic enhancement.

Magnetic resonance imaging (MRI) contrast is generally contraindicated in the pregnant patient because gadolinium can cross the placenta and enter fetal circulation. There is experimental evidence showing the potential of the gadolinium ion to be freed from its chelate molecule and potentially enter the amniotic fluid ( ). Its effect on the fetus is unknown, and because of the association with nephrogenic systemic fibrosis in adults with impaired kidney function this consideration has led to a relative contraindication for the use of gadolinium in pregnant women. Other consensus groups have suggested that less toxic contrast media might be considered for use in MRI in pregnant women. In any case, there should be a strong, well-documented, thoughtful risk-benefit analysis supporting the benefits of a contrast-enhanced MRI study compared with theoretical but possible effects of free gadolinium ions on a developing fetus.

In a normal lactating breast, studies have shown that MRI can find breast cancer. A normal lactating breast will show dense, enhancing, diffuse glandular tissue and widespread high signal throughout the tissue on T2-weighted images. Breast cancer in a lactating breast on MRI shows higher signal intensity in the initial enhancement phase compared with normal surrounding lactational breast tissue (allowing the cancer to be detected), with that cancer showing a washout or plateau pattern in the late phases in the rare reported cases in the radiology literature.

A multidisciplinary approach to the pregnant patient is the cornerstone of care. Women with stages I and IIA breast cancer diagnosed during pregnancy have similar survival rates compared with nonpregnant women. However, a 2012 meta-analysis by Azim of 30 studies suggests pregnancy-associated breast cancers (cancers diagnosed postpartum) have a poorer prognosis compared with that of nonpregnant women. In pregnancy, diagnostic delays may cause breast cancer to be detected at a later stage, leading to a worse prognosis.

Treatment goals for pregnancy-associated breast cancer are the same as for nonpregnant women, which is to obtain both local and systemic control of the cancer, with the additional goal of minimizing fetal harm. Studies have shown that termination of the pregnancy does not usually improve patient survival, and the decision to terminate or continue the pregnancy is a personal one. However, the pregnancy gestational age can affect the treatment course since chemotherapy cannot be given in the first 12 weeks of gestation (the period of fetal organogenesis). Chemotherapy has been used safely in women after the first trimester. On the other hand, local control of the cancer by surgery can be performed at any gestational age with minimal risk to the fetus. Modified radical mastectomy was the usual treatment for pregnant women, who discuss breast-conserving surgery with their team just like nonpregnant patients. If women choose breast conservation, and radiation therapy is needed, radiation treatments would need to be postponed until they are postpartum. Pregnancy is an absolute contraindication for radiation therapy because of high fetal radiation dosages.

Benign conditions are the most frequent cause of breast masses in pregnant or lactating patients. Lactational mastitis is a common complication of breast feeding in which the breast becomes painful, indurated, and tender, usually as a result of Staphylococcus aureus infection. A cracked nipple may be the port of entry for the infecting bacteria, but it can be prevented by good nipple hygiene and care, along with frequent nursing to avoid breast engorgement. Treatment is administration of antibiotics and continuation of breast feeding. On occasion, antibiotic therapy is not sufficient to treat mastitis. If a hot, swollen, painful breast does not respond to antibiotics, ultrasound may identify an abscess and guide percutaneous drainage. On mammography, an abscess is a developing asymmetry or mass in a background of breast edema; it does not usually contain gas and is frequently located in the subareolar region ( Fig. 10.12 ). On ultrasound, abscesses are fluid-filled structures with irregular margins in the early phase, but circumscribed margins develop in the later phase as the walls of the abscess form. The abscess may contain debris or multiple septations, which may be drained under ultrasound guidance, but some residua may remain because of thick debris. Ultrasound-guided percutaneous drainage may be curative in small abscesses <2.5 cm ( ). Drainage may be palliative or curative in larger abscesses ( ), but repeated drainages may be needed. If the abscess does not resolve or is refractory to either aspiration alone or catheter drainage placement, surgical incision and drainage may be needed. Some investigators report using ultrasound-guided aspiration for abscess irrigation and instilling antibiotics directly into the abscess cavity. This aids in resolution of the abscess and is done sometimes with percutaneous drain placement.

Both fibroadenomas and lactating adenomas are solid benign tumors diagnosed during pregnancy. Growth of preexisting fibroadenomas may be stimulated by elevated hormone levels of pregnancy, and the fibroadenoma may become clinically apparent. Infarction of fibroadenomas has been reported in the literature during pregnancy as well. On the other hand, the lactating adenoma is a firm, painless palpable mass occurring late in pregnancy or during lactation. The lactating adenoma is a circumscribed, lobulated mass containing distended tubules with an epithelial lining. The mass can enlarge rapidly during pregnancy and regress after cessation of lactation. Ultrasound typically shows an oval, well-defined hypoechoic mass that may contain echogenic bands representing the fibrotic bands seen on pathology ( Fig. 10.13 ). It is not clear whether lactating adenomas arise from change stimulated by hormonal alterations in a fibroadenoma or tubular adenoma or if these tumors arise de novo.

Sampling of solid masses for histologic examination in a pregnant or lactating patient can be accomplished safely by either percutaneous core biopsy or surgery. Milk fistula produced by damage to the breast ducts is an established, but uncommon complication of these biopsy procedures in women who are in the third trimester of pregnancy or who are lactating.

A galactocele produces a fluid-filled breast mass that can mimic a benign or malignant solid breast mass. On mammography, a galactocele is a round or oval, circumscribed mass of equal or low density ( Fig. 10.14 ). Because a galactocele is filled with milk, the creamy portions of the milk may rise to the nondependent part of the galactocele and produce a rare, but pathognomonic fluid-fluid or fat-fluid appearance on the horizontal beam image (lateromedial view) at mammography. Ultrasound shows a fluid-filled mass that can have a wide range of sonographic appearances, depending on the relative amount of fluid and solid milk components within it. Galactoceles containing mostly fluid have well-defined margins with thin echogenic walls ( Fig. 10.15 ). Galactoceles containing more solid milk components show variable findings, ranging from homogeneous medium-level echoes to heterogeneous contents with fluid clefts. Both distal acoustic enhancement and acoustic shadowing may be seen. A galactocele diagnosis is made by an appropriate history of childbirth and lactation, with aspiration yielding milky fluid and leading to resolution of the mass. Aspiration is usually therapeutic.

Probably Benign Findings (Breast Imaging Reporting and DATA System Category 3)

The Breast Imaging Reporting and Data System (BI-RADS) category 3, or Probably Benign, spectrum of findings ( Box 10.5 ) include three entities: nonpalpable, noncalcified, round or lobulated, circumscribed solid masses ( Fig. 10.16 ); nonpalpable focal asymmetries containing interspersed fat and concave scalloped margins that resemble fibroglandular tissue at diagnostic evaluation ( Fig. 10.17 ); and solitary grouped punctate calcifications ( Fig. 10.18 ). The Probably Benign category arose because mammography screening detects cancer but also uncovers indeterminate but benign-appearing lesions requiring recall. Fine-detail diagnostic mammographic views and ultrasound show that some indeterminate findings are typically benign and are dismissed, others are cancer, and yet others are most likely benign but do not fulfill all criteria for a typically benign finding (probably benign). Findings that qualify for the probably benign BI-RADS category 3 have a low probability (<2%) of malignancy and are followed with short-term mammography, so the diagnostic workup serves as a baseline for short-term, interval follow-up studies. In screening mammography series , , and showed that probably benign findings have a small chance of malignancy. Probably benign BI-RADS category 3 lesions were present in 5, 3, and 5% of all screening studies in their series, respectively.

Probably benign findings usually are found on baseline screening mammograms (no prior mammograms). These findings are designated as BI-RADS category 3 only after a full diagnostic mammographic evaluation and (in some cases) ultrasound. Probably benign findings have 6-month interval imaging only after the workup. BI-RADS 2013 emphasizes that a BI-RADS category 3 assignment is not allowed directly from screening. The reasoning for a full diagnostic workup before a category 3 assignment is that the workup (1) shows that some findings are truly benign such as cysts, skin calcifications, and lymph nodes, which may be returned to screening immediately or (2) shows cancer incompletely evaluated at screening, prompting biopsy.

For a single nonpalpable mass to be probably benign, the margin must be circumscribed around 75% of its edge; the remaining 25% may be obscured but must not show any signs of malignancy, such as ill-defined or spiculated borders. Multiple bilateral similar-appearing circumscribed or partially circumscribed masses may be considered BI-RADS category 2 (benign), because it has been shown that the rate of malignancy among multiple masses is 0.14%, which was lower than the age-matched U.S. incident breast cancer rate of 0.24%. For a focal asymmetry to be considered probably benign, it should not be associated with any mass, suspicious calcifications, or architectural distortion. Other inclusion criteria for the probably benign lesions are that they are nonpalpable, identifiable at imaging, and that the patients are likely to be compliant with follow-up imaging. Criteria that may exclude patients from short-term follow-up include extreme anxiety affecting the patient’s quality of life, pregnancy or planned pregnancy, or a likelihood of noncompliance with follow-up.

Short-term 6-month mammographic unilateral follow-up for category 3 is an alternative to percutaneous core or surgical biopsy. Because the average breast cancer has a tumor volume doubling time of 100 days, growth should be detectable in 2 to 3 years. In the United States probably benign findings are usually followed for 2 to 3 years for this reason.

The usual follow-up for probably benign lesions is a 6-month unilateral mammogram, 12-month bilateral mammogram, and 24-month bilateral mammogram (with optional 36-month bilateral mammogram). If a category 3 finding is stable on the initial 6-month unilateral mammogram, the finding is assigned a category 3 again and recommended for another 6-month follow-up. At the next 6-month follow-up (or 1 year from initial detection) both breasts are imaged (because the opposite breast will be ready for a 12-month screening). If the finding is stable at this first 12-month follow-up, the BI-RADS code is changed to category 2 benign and recommended for a second 1-year follow-up. If the finding is stable at the 24-month follow-up, the B-IRADS code is still category 2 benign, and the patient is returned to screening (with some facilities opting for a 36-month follow-up at this point). Probably benign breast lesions are selected on the basis that they will most likely not change in the time interval. Lesions in which growth is anticipated should undergo biopsy.

reviewed the findings of cancers initially subjected to short-term follow-up to identify imaging criteria that should exclude initial assessment as BI-RADS category 3. They showed that cancers mistakenly classified as category 3 did not qualify as a probably benign finding and included palpable lesions, developing densities, architectural distortion, irregular spiculated masses, growing masses, pleomorphic calcifications, workups showing motion blur on magnification, and lesion progression of any type on mammograms. Their results emphasize that lesions should only be assessed as probably benign and assigned to short-term follow-up (instead of immediate biopsy) after optimal diagnostic workup. Data from the Breast Cancer Surveillance Consortium show that the few cancers that were initially assessed as probably benign are of early-stage and favorable prognosis, but only if full diagnostic imaging evaluation was initially performed. In contrast, cancers that were initially assessed as probably benign based on screening mammographic views and which were not recalled for diagnostic evaluation, were later stage (and of less favorable prognosis).

It is expected that a small number of cancers develop within BI-RADS category 3 lesions, with a probability of malignancy of less than 2%. showed that in their series of probably benign lesions, 0.4% of cases were cancer at follow-up, mostly stage 1 or less, as in the series by .

Category 3 was based on longitudinal data derived from mammography, which is a well-established imaging modality. In clinical practice category 3 has been used with ultrasound and MRI but without the longitudinal data available for mammographic studies, specifically because mammography has been used for a longer period of time. However, data indicate that short-term follow-up may be indicated for palpable or nonpalpable circumscribed round, oval, or gently lobulated masses on mammography and ultrasound.

There is emerging data on MRI category 3 findings with carcinoma probability in MRI ranging from 0.6% to 10% ( ; ). Data-supported recommendations for possible MRI category 3 lesions from BI-RADS 2013 indicate that short-term follow-up may be appropriate of a “1) new unique focus separate from background parenchymal enhancement (BPE) but has benign morphologic and kinetic features and 2) a mass on an initial examination with benign morphologic and kinetic features” ( ). Normal background BPE is seen on almost all MRI examinations, and published data suggest that BPE should not be followed as a category 3 finding ( ). There should be caution regarding inappropriate overuse of the probably benign category in MRI. Among three single-institutional studies a high number, 8.5% ( ), 17% ( ), and 24% ( ), of the MRI cases were assessed as probably benign with a recommendation for short-term follow-up MRI. These numbers are substantially higher than those reported for mammographic lesions.

Nipple Discharge and Galactography

Nipple discharge is a common reason for women to seek medical advice. Benign nipple discharge usually arises from multiple ducts, whereas nipple discharge from a papilloma or DCIS usually occurs from a single duct. Nipple discharge is of particular concern if it is spontaneous and from a single duct or if the discharge is bloody. Women may describe intermittent discharge producing tiny stains on their brassiere or nightgown, or they may be able to elicit the discharge themselves. Some women present for imaging evaluation after positive findings from ductal lavage in conjunction with an abnormal cytologic evaluation.

The most frequent causes of both nonbloody and bloody nipple discharge are benign conditions. The most common mass producing a bloody nipple discharge is a benign intraductal papilloma, with only approximately 5% of women found to have malignancy at biopsy. The bloody nipple discharge associated with papillomas is caused by twisting of the papilloma on its fibrovascular stalk with subsequent infarction and bleeding. Other causes of bloody discharge are cancer, benign findings such as duct hyperplasia/ectasia, and pregnancy as a result of rapidly proliferating breast tissue. Causes of nonbloody nipple discharge are fibrocystic change, medications acting as dopamine receptor blockers or dopamine-depleting drugs, rapid breast growth during adolescence, chronic nipple squeezing, or tumors producing prolactin or prolactin-like substances ( Table 10.2 ).

Papillomas are benign masses consisting of a fibrovascular stalk with an attachment to the wall and breast duct epithelium; they have a variable cellular pattern and can produce nipple discharge. Papillomas may be single or multiple and may extend along the ducts for quite a distance. When large, papillomas can appear to be encysted and multilobulated. Some pathologists support the theory that peripheral papillomas have an increased risk for the subsequent development of carcinoma, whereas solitary or central papillomas do not. Peripheral papillomas are associated with epithelial proliferation, which may have atypical features, raising the possibility that atypia within a peripheral papilloma increases the risk of malignancy rather than the location of the papilloma itself.

The mammogram is frequently negative in the setting of nipple discharge ( Table 10.3 ). Mammographic findings described in association with nipple discharge include a negative mammogram, a single dilated duct in isolation ( Fig. 10.19 ), and a small mass with or without calcifications in either a papilloma or papillary carcinoma. Ultrasound is frequently done in women with nipple discharge, usually done in the retroareolar region, and is often negative, but occasionally shows fluid-filled dilated ducts with or without an intraductal mass ( Fig. 10.20 ; see 10.19B ). Solid masses in a fluid-filled duct may represent debris, a papilloma, or cancer.

Papillomas on MRI deserve special mention because they mimic cancer by producing a round enhancing mass that frequently has rapid initial early enhancement and a late plateau or washout on kinetic curve analysis, which is indistinguishable from invasive cancer ( Fig. 10.21 ). For this reason, papillomas are a common cause of false-positive MRI-guided breast biopsies. On MRI, intraductal papillomas can have three patterns. The first pattern is a small circumscribed enhancing mass at the terminus of a dilated breast duct, corresponding to the filling defect seen on galactography. The second pattern is an irregular, rapidly enhancing mass with occasional spiculation or rim enhancement in women without nipple discharge; this is the pattern that cannot be distinguished from invasive breast cancer. In some cases, blood or debris in the duct may cause precontrast high duct signal and is a cause of false-negative MRI studies because an enhancing mass cannot be detected against the high signal in the duct. Finally, despite the presence of a papilloma, the MRI may be negative, and the papilloma is undetected on contrast-enhanced fat-suppressed T1-weighted studies. Studies are mixed when recommending MRI for nipple discharge, with some studies showing good results detecting papillomas ( ), whereas others show the value of MRI is limited ( ). Still others have used MRI galactography to show the ducts in an attempt to display pathology or intraductal masses with only limited success. We recommend that if the mammogram and ultrasound are negative, and there is no precontrast high duct signal to obscure enhancing intraductal masses, a negatvie MRI supports follow-up rather than surgery.

Galactography or ductography is a study that investigates single-duct nipple discharge by injecting radiopaque contrast into the discharging duct. When it shows filling defects in the ducts it helps subsequent surgical planning by identifying their location and distance from the nipple. Galactography may also show normal duct anatomy, duct ectasia, or fibrocystic change. To perform galactography, the radiologist wears magnifying glasses and expresses the nipple discharge to pinpoint the discharging duct in the nipple. The radiologist cleans the nipple, may use a topical anesthetic, and with sterile technique, cannulates the discharging duct with a 30-gauge blunt-tipped sialogram needle connected to tubing and a syringe filled with contrast. Usually, the needle will fall painlessly into the duct, but on occasion, warm compresses are needed to relax the duct opening. The radiologist injects 0.2 to 1 mL of contrast into the duct until they feel resistance or the patient feels a sense of fullness in the breast. Because the ducts are quite fragile, pain or burning may indicate duct perforation or contrast extravasation. The cannulation and/or the injection should not be painful. Either symptom is an indication to stop the procedure and reevaluate the situation.

After the injection, the radiologist either tapes the needle in place or withdraws the needle and the contrast-filled duct is sealed with collodion for subsequent craniocaudal and mediolateral mammograms to see the contrast-filled ducts. Magnification views may help to evaluate the ducts for filling defects. After the mammogram, the radiologist expresses the contrast from the ducts by gentle massage. If duct filling is incomplete, if the contrast is diluted by retained secretions, or if an air bubble is simulating an intraductal filling defect, the contrast can be expressed from the nipple and then the duct can be reinjected immediately for a second, better, contrast-filled study.

A normal duct arborizes from a single entry point on the nipple into smaller ducts extending over almost an entire quadrant of the breast. Normal ducts are thin and smooth walled and have no filling defects or wall irregularities ( Fig. 10.22A ). Ductal ectasia is not uncommon; occasionally normal cysts or lobules fill from the dilated ducts ( Fig. 10.22B ). Ectatic ducts without a filling defect are usually normal. However, despite a normal galactogram, surgical excision of the discharging duct may still reveal papillomas or cancer on histology (ie, false-negative study; Fig. 10.22C ).

Ducts containing malignancy or papillomas are typically dilated between the tumor and the nipple. Positive galactograms show a filling defect, an abrupt duct cutoff, or luminal irregularity and distortion ( Figs. 10.23–10.25 ). Tumors causing the abnormal findings may be located inside a fluid-filled dilated duct or may compress the duct from outside the duct walls. On occasion, masses, either papilloma or intracystic cancer, may become encysted ( Fig. 10.26 ). Air bubbles produce filling defects that mimic papilloma or cancer, but they are usually sharply defined and round and change position inside the duct on repeat injection, unlike fixed intraductal tumors. On the galactogram, extravasation is seen as contrast extending outside the duct lumen into the breast tissue and obscuring the underlying breast tissue and ducts ( Fig. 10.27 ). In the rare instance of lymphatic or venous uptake of extravasated contrast, a draining tubular structure leading away from the extravasation site can be seen.

A positive galactogram usually leads to biopsy, either by preoperative needle localization or by ductoscopy. Preoperative needle localization of filling defects after galactography under x-ray guidance may be helpful for surgical planning, especially if the intraductal mass is deep in the breast. Negative galactograms, despite the presence of a papilloma on biopsy, have been reported. Galactography has a sensitivity ranging from 69% to 78% for tumors.

In the early 1990s, surgeons reported using a tiny ductoscope to cannulate a discharging duct for identification of papillomas or other intraductal masses intraoperatively to guide surgery. reported that 16% of women undergoing ductoscopy at surgery had lesions detected by ductoscopy that were not seen on either ductograms or mammograms before surgery.

Nipple and Skin Retraction

Long-standing nipple inversion is not uncommon and is benign if it is present at birth. On the other hand, new nipple inversion is worrisome because retroareolar breast cancers can pull in the nipple by productive fibrosis or invasion, causing the nipple to retract or invert ( Figs. 10.28 and 10.29 ).

Skin retraction or skin dimpling is not uncommon after surgical excisional biopsy. However, in the absence of biopsy, skin or nipple retraction may be a sign of breast cancer caused by superficial cancers tethering or invading the skin and pulling the skin in toward the breast. On physical examination, skin retraction or tethering might become evident when the woman raises her arms as she inspects her breasts in the mirror. Raising her arms or placing her hands on her hips pulls in the pectoralis muscle, which pulls on the cancer, which pulls on the skin, and dimples the skin in toward the cancer. On mammography with a BB marker placement on the site of skin dimpling, a suspicious mass sometimes may be identified under the BB marker ( Fig. 10.30 ).

Breast Edema

On clinical examination, breast edema may be evident as peau d’orange (a term signifying thickening and elevation of the skin around tethered hair follicles, making the skin’s appearance similar to an orange peel). The edematous breast may be larger than the contralateral side. The differential diagnosis for breast edema depends on whether the edema is unilateral or bilateral ( Box 10.6 ). Unilateral breast edema is caused by mastitis, inflammatory cancer ( Figs. 10.31–10.33 ), local obstruction of lymph nodes ( Fig. 10.34 ), trauma ( Fig. 10.35 ), radiation therapy, or coumarin necrosis. Bilateral breast edema is caused by systemic etiologies, such as congestive heart failure, liver disease, anasarca, renal failure ( Fig. 10.36 ), or other conditions that can cause edema elsewhere in the body. Alternatively, bilateral lymphadenopathy or superior vena cava obstruction for any reason may cause bilateral breast edema ( Fig. 10.37 ). The key to diagnosis is to obtain an accurate clinical history and evaluate the breast for any signs of cancer.