{"id":4422463,"date":"2025-01-11T20:06:33","date_gmt":"2025-01-12T02:06:33","guid":{"rendered":"https:\/\/myendoconsult.com\/learn\/topics\/gynecomastia\/"},"modified":"2025-01-20T06:35:50","modified_gmt":"2025-01-20T12:35:50","slug":"gynecomastia","status":"publish","type":"oen_topic","link":"https:\/\/myendoconsult.com\/learn\/topics\/gynecomastia\/","title":{"rendered":"Gynecomastia"},"content":{"rendered":"\n<h2 class=\"wp-block-heading\">GYNECOMASTIA<\/h2>\n\n\n\n<h3 class=\"wp-block-heading\">Definition<\/h3>\n\n\n\n<ul class=\"wp-block-list\">\n<li><strong>Gynecomastia<\/strong> = enlargement of the male breast from increased glandular tissue (not just adipose).<\/li>\n\n\n\n<li>Degree can vary from a small, tender subareolar disk to a full female-like breast.<\/li>\n\n\n\n<li><strong>Differentiate<\/strong>:\n<ol class=\"wp-block-list\">\n<li><strong>True gynecomastia<\/strong> (glandular proliferation)<\/li>\n\n\n\n<li><strong>Pseudogynecomastia<\/strong> (excess adipose).<\/li>\n\n\n\n<li><strong>Breast carcinoma<\/strong> in men.<\/li>\n<\/ol>\n<\/li>\n<\/ul>\n\n\n\n<h3 class=\"wp-block-heading\">Histopathology<\/h3>\n\n\n\n<ul class=\"wp-block-list\">\n<li><strong>Stimulation of ducts, stroma<\/strong>:\n<ul class=\"wp-block-list\">\n<li>Ducts: lengthening, branching, budding of new ducts (no alveoli).<\/li>\n\n\n\n<li>Epithelial hyperplasia.<\/li>\n\n\n\n<li>Increased, often hyalinized stromal tissue.<\/li>\n<\/ul>\n<\/li>\n\n\n\n<li><strong>Pathogenesis<\/strong>: <strong>Decreased androgen : estrogen ratio<\/strong>.<\/li>\n<\/ul>\n\n\n\n<figure class=\"wp-block-embed is-type-video is-provider-youtube wp-block-embed-youtube wp-embed-aspect-16-9 wp-has-aspect-ratio\"><div class=\"wp-block-embed__wrapper\">\n<iframe loading=\"lazy\" title=\"Evaluation of Gynecomastia : A Concise Review of Pathophysiology\" width=\"500\" height=\"281\" src=\"https:\/\/www.youtube.com\/embed\/oi0piaowpC4?feature=oembed\" frameborder=\"0\" allow=\"accelerometer; autoplay; clipboard-write; encrypted-media; gyroscope; picture-in-picture; web-share\" referrerpolicy=\"strict-origin-when-cross-origin\" allowfullscreen><\/iframe>\n<\/div><\/figure>\n\n\n\n<hr class=\"wp-block-separator has-alpha-channel-opacity\"\/>\n\n\n\n<h2 class=\"wp-block-heading\">PHYSIOLOGIC (Benign) CAUSES<\/h2>\n\n\n\n<ol class=\"wp-block-list\">\n<li><strong>Neonatal<\/strong>\n<ul class=\"wp-block-list\">\n<li>Maternal estrogen crosses placenta \u2192 slight male breast enlargement, sometimes \u201cwitch\u2019s milk.\u201d<\/li>\n\n\n\n<li>Typically subsides within weeks.<\/li>\n<\/ul>\n<\/li>\n\n\n\n<li><strong>Pubertal Gynecomastia<\/strong>\n<ul class=\"wp-block-list\">\n<li>Occurs in ~50% of adolescent boys, often tender and bilateral.<\/li>\n\n\n\n<li>Related to enhanced aromatization of androgens to estrogens while testosterone is still at subadult levels.<\/li>\n\n\n\n<li><strong>Most common single cause<\/strong> of gynecomastia.<\/li>\n\n\n\n<li>Usually resolves spontaneously within 1\u20132 years in &gt;90% of cases.<\/li>\n\n\n\n<li>Persistence into adulthood is called <strong>persistent pubertal gynecomastia<\/strong>.<\/li>\n<\/ul>\n<\/li>\n\n\n\n<li><strong>Involutional (Aging)<\/strong>\n<ul class=\"wp-block-list\">\n<li>Mild breast enlargement in older men, likely due to <strong>decreasing testosterone<\/strong> production with age.<\/li>\n<\/ul>\n<\/li>\n<\/ol>\n\n\n\n<hr class=\"wp-block-separator has-alpha-channel-opacity\"\/>\n\n\n\n<h2 class=\"wp-block-heading\">PATHOLOGIC CAUSES<\/h2>\n\n\n\n<h3 class=\"wp-block-heading\">1. Medication-Induced<\/h3>\n\n\n\n<ul class=\"wp-block-list\">\n<li><strong>Common<\/strong>: many drugs alter androgen\/estrogen balance or act directly on breast tissue.<\/li>\n\n\n\n<li>Examples:\n<ul class=\"wp-block-list\">\n<li><strong>Antiandrogens<\/strong> (flutamide, spironolactone)<\/li>\n\n\n\n<li><strong>Antibiotics<\/strong> (isoniazid, ketoconazole)<\/li>\n\n\n\n<li><strong>Oncologic<\/strong> agents (alkylators, imatinib)<\/li>\n\n\n\n<li><strong>Anti-ulcer<\/strong> meds (cimetidine)<\/li>\n\n\n\n<li><strong>Cardiovascular<\/strong> (digoxin, methyldopa)<\/li>\n\n\n\n<li><strong>Illicit<\/strong> drugs (marijuana, heroin)<\/li>\n\n\n\n<li><strong>Hormonal<\/strong> (estrogens, androgens, anabolic steroids, hCG)<\/li>\n\n\n\n<li><strong>Psychoactive<\/strong> (haloperidol, phenothiazines)<\/li>\n<\/ul>\n<\/li>\n\n\n\n<li><strong>Mechanisms<\/strong>:\n<ul class=\"wp-block-list\">\n<li>Block testosterone receptors (e.g., spironolactone).<\/li>\n\n\n\n<li>Enhance peripheral conversion of testosterone \u2192 estradiol.<\/li>\n\n\n\n<li>Increase testosterone clearance.<\/li>\n\n\n\n<li>Decrease gonadotropin secretion \u2192 low testosterone.<\/li>\n<\/ul>\n<\/li>\n<\/ul>\n\n\n\n<h3 class=\"wp-block-heading\">2. Hypogonadism<\/h3>\n\n\n\n<ul class=\"wp-block-list\">\n<li><strong>Primary (testicular failure)<\/strong>:\n<ul class=\"wp-block-list\">\n<li>e.g., <strong>Klinefelter syndrome<\/strong> (47,XXY), infection, trauma, radiation.<\/li>\n\n\n\n<li>Low testosterone \u2192 unopposed estrogen action.<\/li>\n<\/ul>\n<\/li>\n\n\n\n<li><strong>Secondary (pituitary failure)<\/strong>:\n<ul class=\"wp-block-list\">\n<li>e.g., Nonfunctioning pituitary macroadenoma \u2192 LH\/FSH deficiency.<\/li>\n\n\n\n<li>Prolactinomas \u2192 decreased LH\/FSH, low T \u2192 but prolactin itself does not directly cause gynecomastia.<\/li>\n<\/ul>\n<\/li>\n<\/ul>\n\n\n\n<h3 class=\"wp-block-heading\">3. Chronic Liver Disease (Cirrhosis)<\/h3>\n\n\n\n<ul class=\"wp-block-list\">\n<li><strong>Mechanisms<\/strong>:\n<ul class=\"wp-block-list\">\n<li>Increased adrenal androgens.<\/li>\n\n\n\n<li>Enhanced aromatization \u2192 higher estrogens.<\/li>\n\n\n\n<li>Many cirrhotic patients on spironolactone.<\/li>\n<\/ul>\n<\/li>\n<\/ul>\n\n\n\n<h3 class=\"wp-block-heading\">4. Malnutrition \/ Cachexia<\/h3>\n\n\n\n<ul class=\"wp-block-list\">\n<li><strong>Secondary Hypogonadism<\/strong> occurs (low LH\/FSH) while adrenal estrogen production persists \u2192 low androgen : estrogen ratio \u2192 gynecomastia.<\/li>\n<\/ul>\n\n\n\n<h3 class=\"wp-block-heading\">5. Tumors Producing hCG<\/h3>\n\n\n\n<ul class=\"wp-block-list\">\n<li><strong>Testicular germ cell tumors<\/strong> (choriocarcinoma, embryonal carcinoma) \u2192 hypersecrete hCG \u2192 \u2191testosterone but also \u2191aromatase activity \u2192 more estrogens.<\/li>\n\n\n\n<li><strong>Extragonadal<\/strong> hCG tumors (lung, stomach, kidney, liver).<\/li>\n<\/ul>\n\n\n\n<h3 class=\"wp-block-heading\">6. Hyperthyroidism<\/h3>\n\n\n\n<ul class=\"wp-block-list\">\n<li>~25% men with hyperthyroidism have gynecomastia.\n<ul class=\"wp-block-list\">\n<li>Mechanisms:\n<ul class=\"wp-block-list\">\n<li>Increased LH secretion \u2192 more T \u2192 more peripheral aromatization \u2192 more E.<\/li>\n\n\n\n<li>Increased SHBG \u2192 lowers free T.<\/li>\n<\/ul>\n<\/li>\n<\/ul>\n<\/li>\n<\/ul>\n\n\n\n<h3 class=\"wp-block-heading\">7. Estrogen-Secreting Tumors<\/h3>\n\n\n\n<ul class=\"wp-block-list\">\n<li><strong>Adrenal tumors<\/strong> (often adrenocortical carcinomas) rarely produce high estrogen \u2192 gynecomastia.<\/li>\n<\/ul>\n\n\n\n<h3 class=\"wp-block-heading\">8. Idiopathic Gynecomastia<\/h3>\n\n\n\n<ul class=\"wp-block-list\">\n<li>No identifiable cause found; possibly slight hormonal imbalance or sensitivity at breast tissue.<\/li>\n<\/ul>\n\n\n\n<p><\/p>\n\n\n\n<p><a href=\"https:\/\/myendoconsult.com\/learn\/download\/gynecomastia-evaluation-lecture-notes\/\" data-type=\"link\" data-id=\"https:\/\/myendoconsult.com\/learn\/download\/gynecomastia-evaluation-lecture-notes\/\">Download the lecture notes for this presentation.<\/a> <\/p>\n\n\n\n<p><\/p>\n","protected":false},"excerpt":{"rendered":"<p>GYNECOMASTIA Definition Histopathology PHYSIOLOGIC (Benign) CAUSES PATHOLOGIC CAUSES 1. Medication-Induced 2. Hypogonadism 3. Chronic Liver Disease (Cirrhosis) 4. Malnutrition \/ Cachexia 5. Tumors Producing hCG 6. Hyperthyroidism 7. Estrogen-Secreting Tumors 8. Idiopathic Gynecomastia Download the lecture notes for this presentation.<\/p>\n","protected":false},"featured_media":0,"template":"","oen_topic_chapter":[685],"class_list":["post-4422463","oen_topic","type-oen_topic","status-publish","hentry","oen_topic_chapter-reproductive-disorders","post-wrapper","thrv_wrapper"],"_links":{"self":[{"href":"https:\/\/myendoconsult.com\/learn\/wp-json\/wp\/v2\/oen_topic\/4422463","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/myendoconsult.com\/learn\/wp-json\/wp\/v2\/oen_topic"}],"about":[{"href":"https:\/\/myendoconsult.com\/learn\/wp-json\/wp\/v2\/types\/oen_topic"}],"version-history":[{"count":4,"href":"https:\/\/myendoconsult.com\/learn\/wp-json\/wp\/v2\/oen_topic\/4422463\/revisions"}],"predecessor-version":[{"id":4422900,"href":"https:\/\/myendoconsult.com\/learn\/wp-json\/wp\/v2\/oen_topic\/4422463\/revisions\/4422900"}],"wp:attachment":[{"href":"https:\/\/myendoconsult.com\/learn\/wp-json\/wp\/v2\/media?parent=4422463"}],"wp:term":[{"taxonomy":"oen_topic_chapter","embeddable":true,"href":"https:\/\/myendoconsult.com\/learn\/wp-json\/wp\/v2\/oen_topic_chapter?post=4422463"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}