madman
Super Moderator
Getting real deep here!
TEACHING POINTS
*In the appropriate clinical setting, mammography is diagnostic for gynecomastia, which is the most common reason for presentation with a palpable lump, an area of focal pain, or breast enlargement; and mammography is highly sensitive in the male breast due to the typically lower amount of fibroglandular tissue compared with that in women.
*Although ductal and stromal proliferation in these patients may be extensive, males with gynecomastia rarely have substantial lobular proliferation due to a lack of progesterone.
*Gynecomastia is the most common cause of presentation with an area of palpable concern, breast pain, or breast enlargement in men.
*Axillary US should be performed in all male patients with breast masses suspicious for cancer because approximately one-half of MBCs involve the axillary lymph nodes.
*Papillary carcinoma has been reported to be twice as prevalent in patients with MBC than in those with FBC. This is thought to be due to the predominantly larger ducts that make up typical male breast tissue, in which these neoplasms tend to occur.
The number of men undergoing breast imaging has increased in recent years, according to some reports. Most male breast concerns are related to benign causes, most commonly gynecomastia. The range of abnormalities typically encountered in the male breast is less broad than that encountered in women, given that lobule formation rarely occurs in men. Other benign causes of male breast palpable abnormalities with characteristic imaging findings include lipomas, sebaceous or epidermal inclusion cysts, and intramammary lymph nodes. Male breast cancer (MBC) is rare, representing up to 1% of breast cancer cases, but some data indicate that its incidence is increasing. MBC demonstrates some clinical features that overlap with those of gynecomastia, including a propensity for the subareolar breast. Men with breast cancer tend to present at a later stage than do women. MBC typically has similar imaging features to those of female breast cancer, often characterized by an irregular mass that may have associated calcifications. Occasionally, however, MBC has a benign-appearing imaging phenotype, with an oval shape and circumscribed margins, and therefore most solid breast masses in men require tissue diagnosis. Histopathologic evaluation may alternatively reveal other benign breast masses found in men, including papillomas, myofibroblastomas, and hemangiomas. Radiologists must be familiar with the breadth of male breast abnormalities to meet the rising challenge of caring for these patients.
Introduction
Although the small number of men relative to women who present with breast concerns leads to difficulty in determining trends, diagnostic imaging has been reported (1,2) to have been increasingly used in recent years for evaluation of male breast concerns. Most male breast symptoms have benign causes, the majority of which are related to gynecomastia (3). Male breast cancer (MBC) is a rare cause of symptoms in men, but some data indicate that its incidence is increasing (1,4–8). MBC is more likely to be diagnosed at an advanced stage than is female breast cancer (FBC) (9,10). Therefore, an expedient diagnosis of cancer in symptomatic men presenting for imaging is of the utmost importance. MBC often demonstrates suspicious imaging features similar to those of FBC but occasionally has a deceptively benign imaging appearance, which has been theorized to contribute to a delay in diagnosis of MBC (11). These facts emphasize the importance of radiologist familiarity with the spectrum of imaging findings of benign and malignant breast abnormalities in men.
This article reviews male breast development, methods of imaging and pathophysiologic characteristics of the male breast, imaging of gynecomastia, and imaging findings of MBC and benign male breast abnormalities.
Male Breast Development
Methods of Imaging the Male Breast
Gynecomastia
Gynecomastia is an increase in ductal and stromal tissue in male patients secondary to an increased ratio of estrogens to androgens (Fig 1). Gynecomastia may be physiologic (ie,related to an expected deviation from the normal hormonal balance in patients of specific age groups) or pathologic(ie, occurring when the inciting hormonal derangement is caused by extrinsic influences or intrinsic conditions resulting in a systemic increase in estrogen). Although ductal and stromal proliferation in these patients may be extensive, males with gynecomastia rarely have substantial lobular proliferation due to a lack of progesterone. Therefore, lobular abnormalities seen in women, such as fibroadenomas, phyllodes tumors, most fibrocystic changes, lobular carcinoma in situ, and invasive lobular carcinoma (ILC), are rarely seen in men (13,21,22).
*Physiologic gynecomastia
*Pathologic gynecomastia
*Pseudogynecomastia
Male Breast Cancer
Pathologic and Imaging Findings of MBC
*Invasive Ductal Carcinoma
*Ductal Carcinoma in Situ
*Papillary Carcinoma
*Invasive Lobular Carcinoma
*Other Male Breast Malignancies
Treatment of MBC
Benign Male Breast Entities
*Abscess
*Hemangioma
*Myofibroblastoma
*Intraductal Papilloma
*Pseudoangiomatous Stromal Hyperplasia
*Parenchymal Cyst
*Fibroadenoma
Breast Imaging in Transgender Patients
Breast Cancer Screening in Men at High Risk
Conclusion
A variety of breast abnormalities can be seen in men, and some entities demonstrate clinical or imaging findings specific to men in comparison to those seen in women. Gynecomastia is the most common cause of presentation for breast imaging in men, while MBC is a rare but important abnormality that must be excluded in symptomatic men. Gynecomastia and MBC share a predilection for the subareolar breast, and some cases of gynecomastia may demonstrate suspicious imaging findings similar to those of MBC, requiring biopsy. However, most cases of gynecomastia and MBC can be distinguished on the basis of other differences in clinical and imaging findings.
Other less common benign causes of male breast symptoms include abscesses, hemangiomas, myofibroblastomas,papillomas, and pseudoangiomatous stromal hyperplasia (PASH). Because lobules generally are not present in the male breast, common benign breast masses in women such as fibroadenomas and cysts are rare in men. In addition, MBC occasionally has deceptively benign-appearing imaging features such as mostly circumscribed margins and an oval shape. Thus, most solid breast masses in men require biopsy. In a male patient with a breast mass requiring biopsy, US evaluation of the ipsilateral axilla should be performed, given the high rate of involvement of the regional lymph nodes in MBC.
Men have increasingly presented for breast imaging in recent years. MBC incidence is rising, and men with MBC typically receive the diagnosis at a later stage than do women because of delayed presentation. Radiologists must be familiar with the varied clinical and imaging findings of MBC and other causes of male breast concerns to avoid further delay in diagnosis of MBC.
TEACHING POINTS
*In the appropriate clinical setting, mammography is diagnostic for gynecomastia, which is the most common reason for presentation with a palpable lump, an area of focal pain, or breast enlargement; and mammography is highly sensitive in the male breast due to the typically lower amount of fibroglandular tissue compared with that in women.
*Although ductal and stromal proliferation in these patients may be extensive, males with gynecomastia rarely have substantial lobular proliferation due to a lack of progesterone.
*Gynecomastia is the most common cause of presentation with an area of palpable concern, breast pain, or breast enlargement in men.
*Axillary US should be performed in all male patients with breast masses suspicious for cancer because approximately one-half of MBCs involve the axillary lymph nodes.
*Papillary carcinoma has been reported to be twice as prevalent in patients with MBC than in those with FBC. This is thought to be due to the predominantly larger ducts that make up typical male breast tissue, in which these neoplasms tend to occur.
The number of men undergoing breast imaging has increased in recent years, according to some reports. Most male breast concerns are related to benign causes, most commonly gynecomastia. The range of abnormalities typically encountered in the male breast is less broad than that encountered in women, given that lobule formation rarely occurs in men. Other benign causes of male breast palpable abnormalities with characteristic imaging findings include lipomas, sebaceous or epidermal inclusion cysts, and intramammary lymph nodes. Male breast cancer (MBC) is rare, representing up to 1% of breast cancer cases, but some data indicate that its incidence is increasing. MBC demonstrates some clinical features that overlap with those of gynecomastia, including a propensity for the subareolar breast. Men with breast cancer tend to present at a later stage than do women. MBC typically has similar imaging features to those of female breast cancer, often characterized by an irregular mass that may have associated calcifications. Occasionally, however, MBC has a benign-appearing imaging phenotype, with an oval shape and circumscribed margins, and therefore most solid breast masses in men require tissue diagnosis. Histopathologic evaluation may alternatively reveal other benign breast masses found in men, including papillomas, myofibroblastomas, and hemangiomas. Radiologists must be familiar with the breadth of male breast abnormalities to meet the rising challenge of caring for these patients.
Introduction
Although the small number of men relative to women who present with breast concerns leads to difficulty in determining trends, diagnostic imaging has been reported (1,2) to have been increasingly used in recent years for evaluation of male breast concerns. Most male breast symptoms have benign causes, the majority of which are related to gynecomastia (3). Male breast cancer (MBC) is a rare cause of symptoms in men, but some data indicate that its incidence is increasing (1,4–8). MBC is more likely to be diagnosed at an advanced stage than is female breast cancer (FBC) (9,10). Therefore, an expedient diagnosis of cancer in symptomatic men presenting for imaging is of the utmost importance. MBC often demonstrates suspicious imaging features similar to those of FBC but occasionally has a deceptively benign imaging appearance, which has been theorized to contribute to a delay in diagnosis of MBC (11). These facts emphasize the importance of radiologist familiarity with the spectrum of imaging findings of benign and malignant breast abnormalities in men.
This article reviews male breast development, methods of imaging and pathophysiologic characteristics of the male breast, imaging of gynecomastia, and imaging findings of MBC and benign male breast abnormalities.
Male Breast Development
Methods of Imaging the Male Breast
Gynecomastia
Gynecomastia is an increase in ductal and stromal tissue in male patients secondary to an increased ratio of estrogens to androgens (Fig 1). Gynecomastia may be physiologic (ie,related to an expected deviation from the normal hormonal balance in patients of specific age groups) or pathologic(ie, occurring when the inciting hormonal derangement is caused by extrinsic influences or intrinsic conditions resulting in a systemic increase in estrogen). Although ductal and stromal proliferation in these patients may be extensive, males with gynecomastia rarely have substantial lobular proliferation due to a lack of progesterone. Therefore, lobular abnormalities seen in women, such as fibroadenomas, phyllodes tumors, most fibrocystic changes, lobular carcinoma in situ, and invasive lobular carcinoma (ILC), are rarely seen in men (13,21,22).
*Physiologic gynecomastia
*Pathologic gynecomastia
*Pseudogynecomastia
Male Breast Cancer
Pathologic and Imaging Findings of MBC
*Invasive Ductal Carcinoma
*Ductal Carcinoma in Situ
*Papillary Carcinoma
*Invasive Lobular Carcinoma
*Other Male Breast Malignancies
Treatment of MBC
Benign Male Breast Entities
*Abscess
*Hemangioma
*Myofibroblastoma
*Intraductal Papilloma
*Pseudoangiomatous Stromal Hyperplasia
*Parenchymal Cyst
*Fibroadenoma
Breast Imaging in Transgender Patients
Breast Cancer Screening in Men at High Risk
Conclusion
A variety of breast abnormalities can be seen in men, and some entities demonstrate clinical or imaging findings specific to men in comparison to those seen in women. Gynecomastia is the most common cause of presentation for breast imaging in men, while MBC is a rare but important abnormality that must be excluded in symptomatic men. Gynecomastia and MBC share a predilection for the subareolar breast, and some cases of gynecomastia may demonstrate suspicious imaging findings similar to those of MBC, requiring biopsy. However, most cases of gynecomastia and MBC can be distinguished on the basis of other differences in clinical and imaging findings.
Other less common benign causes of male breast symptoms include abscesses, hemangiomas, myofibroblastomas,papillomas, and pseudoangiomatous stromal hyperplasia (PASH). Because lobules generally are not present in the male breast, common benign breast masses in women such as fibroadenomas and cysts are rare in men. In addition, MBC occasionally has deceptively benign-appearing imaging features such as mostly circumscribed margins and an oval shape. Thus, most solid breast masses in men require biopsy. In a male patient with a breast mass requiring biopsy, US evaluation of the ipsilateral axilla should be performed, given the high rate of involvement of the regional lymph nodes in MBC.
Men have increasingly presented for breast imaging in recent years. MBC incidence is rising, and men with MBC typically receive the diagnosis at a later stage than do women because of delayed presentation. Radiologists must be familiar with the varied clinical and imaging findings of MBC and other causes of male breast concerns to avoid further delay in diagnosis of MBC.
