16.3 Male Patients and Lactating Breast

Male patients on the 2.B outline

The 2025 specifications list male patients (worded as male sex patients on the outline) as a patient-variance item. Most male breast imaging is diagnostic, not population screening. The positioning problem is a small, often hairy mound sitting on a thick pectoralis, with a clinical question that is usually “gynecomastia versus mass.”

Quick Answer: Use a small paddle. Image CC and MLO of the symptomatic side. Treat a hard mass eccentric to the nipple as a mass workup, not as typical gynecomastia.

Gynecomastia versus an eccentric mass

Gynecomastia is proliferation of retroareolar ducts and stroma. It is often tender. Mammographically it is a fan-shaped or flame-shaped density that starts at the nipple and blends into surrounding fat. It may be unilateral or bilateral and asymmetric. Pseudogynecomastia is fatty enlargement without that retroareolar glandular flare.

Male breast cancer is uncommon — on the order of 1% of breast cancers — but it is the finding you must not bury under a gynecomastia assumption. It more often presents as a hard, painless mass eccentric to the nipple, sometimes with nipple retraction, skin change, nipple discharge, or axillary adenopathy. Calcifications are less common than in female breast cancer; when they are present they are treated as suspicious until worked up. Your positioning implication is simple: if the palpable finding is not centered under the nipple, the small retroareolar CC is not enough. The eccentric site must be included, marked, and fully compressed.

Views, paddles, and the pectoralis problem

Male mammography is often CC and MLO of the symptomatic side. Add the contralateral breast when the radiologist needs a comparison (asymmetric gynecomastia, high-risk history, or an order for bilateral imaging). Do not silently skip the other side if the order is bilateral.

Use a smaller paddle or spot paddle so the small mound cannot slide and so the paddle does not spend its travel crushing pectoralis instead of breast. Too much pectoralis under the paddle is a classic male-MLO failure: the muscle holds the paddle up and the anterior retroareolar tissue — exactly where gynecomastia and many cancers live — is under-compressed. Angle the MLO to the muscle, then lift the small breast up and out so glandular tissue, not armpit muscle, is the compressed organ.

Chest hair prevents the CC from sticking. An FB view can help when the patient is mobile. Warm the receptor, use the facility’s approved skin-prep, and do not shave in the mammography room as a routine “fix.” If the nipple will not stay in profile, a second CC with a skin marker on the nipple is better than a guess.

Modality choice sits next to positioning. Classic, bilateral, tender gynecomastia in a young man may not need imaging at all once the clinician is satisfied. When imaging is indicated, men 25 and older with an indeterminate palpable finding typically start with mammography; younger men often start with ultrasound. You still need to know how to position the mammogram when it is the ordered study.

Lactating breast

A lactating breast is dense, engorged, and vascular. Cooper ligaments are under tension, the IMF is wet, and compression is more uncomfortable than in the same patient before pregnancy. Mammograms look like extremely dense tissue with prominent ducts. That density can hide masses, which is why emptying the breast and adding views matter.

Nurse or pump before the exam

If the patient can nurse or pump immediately before the appointment, do it. Residual milk increases thickness, density, and pain. An emptied breast compresses further, which lowers dose for the same image quality and gives the radiologist a less white map. Provide a private space and time; this is patient variance, not a courtesy extra.

You may still need extra views: anterior compression if the posterior breast is much thicker, spot compression of a palpable area, a true lateral for a suspected fat-fluid level, or additional CCs if engorgement kept tissue off the first image. Ultrasound is a frequent companion exam for a palpable lactating breast; your mammogram still has to include the site.

Galactocele context

A galactocele is a milk-retention cyst. It appears during lactation or after weaning, often as a palpable retroareolar mass. On a horizontal-beam true lateral it may show a fat-fluid level. It is usually benign, but it is not a reason to skip inclusion of the finding or to tell the patient that “all lumps in breastfeeding are milk.” Mark the palpable site. If the order is diagnostic, complete the mammographic views the protocol requires and leave characterization to the radiologist, who may add ultrasound.

Other lactational findings you will be asked to include, not diagnose, include galactoceles, lactating adenomas, and, rarely, pregnancy-associated breast cancer. A hard, eccentric, or growing mass in a lactating patient is imaged, not deferred as “engorgement.”

Pregnancy: delay screening when possible; image if indicated

Pregnancy is not a separate numbered 2.B bullet, but it is the clinical setting that produces many lactating and peripartum exams. Delay screening mammography when it is reasonable to wait until after delivery — and many facilities also wait until lactation decreases density — because screening is a population test without a current clinical target. That delay is a timing decision, not a rule that mammography is forbidden in pregnancy.

Diagnostic mammography is performed when it is clinically indicated: a suspicious palpable mass, bloody discharge, or other findings the radiologist or referring clinician will not wait on. Fetal dose from a properly collimated mammogram is very low. Do not invent a forbidden-dose cutoff, a banned kVp, or a “never in the first trimester” absolute for indicated diagnostic imaging. Those made-up rules fail both the exam and the patient with pregnancy-associated breast cancer.

Discuss abdominal shielding. A wrap or apron can be offered for comfort and for ALARA communication. Much of any fetal dose is internal scatter, so a shield is not a magic barrier, but it is a reasonable, commonly used discussion and practice when the patient wants it and it does not interfere with positioning. Do not skip an indicated diagnostic mammogram because a shield is unavailable, and do not refuse shielding as “pointless” if offering it helps the patient complete a needed exam.

Tomosynthesis, extra views, and ultrasound proceed according to the diagnostic protocol. Contrast-enhanced breast MRI in pregnancy is a different conversation (gadolinium concerns) and is not a substitute talking point for “we cannot do mammography.”

Exam traps

Do not image only an MLO of a male breast because “there is not enough tissue for a CC.” If there is tissue to palpate, there is tissue for a small-paddle CC or FB. Do not assume bilateral imaging is automatic or automatic-not; follow the order and the clinical need for comparison. Do not skip pumping advice for a lactating patient and then call the exam limited because of density you could have reduced. Do not tell a pregnant patient that mammography is categorically prohibited; tell her screening can often wait and that diagnostic imaging can proceed with a shielding discussion when the finding cannot wait.