{"id":45120,"date":"2025-08-05T14:04:50","date_gmt":"2025-08-05T06:04:50","guid":{"rendered":"https:\/\/medicine.nus.edu.sg\/pathweb\/?page_id=45120"},"modified":"2025-09-18T09:49:19","modified_gmt":"2025-09-18T01:49:19","slug":"msk-1","status":"publish","type":"page","link":"https:\/\/medicine.nus.edu.sg\/pathweb\/cytopath\/cyto-mystery-cases\/msk-1\/","title":{"rendered":"Mystery cases &#8211; Musculoskeletal 1"},"content":{"rendered":"\r\n<h2>Musculoskeletal 1<\/h2>\r\n<h1>A groovy scapular lesion<\/h1>\r\n<p><strong>Clinical history<\/strong>: A 43-year-old lady presented with 3-month history of left shoulder pain. Plain film X-ray shows a well-defined lytic lesion in the left scapula. A CT-guided core biopsy of the lesion is performed and a cytology imprint is shown.<\/p>\r\n<p><iframe src=\"https:\/\/player.vimeo.com\/video\/1094651731?h=0cfe2ea625&amp;badge=0&amp;autopause=0&amp;player_id=0&amp;app_id=58479&amp;autoplay=1\" frameborder=\"0\" allow=\"autoplay; fullscreen; picture-in-picture; clipboard-write; encrypted-media; web-share\" title=\"A groovy scapular lesion: https:\/\/blog.nus.edu.sg\/cytoweb\/case-of-the-month\/july-2020-a-groovy-scapular-lesion\/\"><\/iframe> <a href=\"#\" id=\"fl-accordion--label-0\" aria-controls=\"fl-accordion--panel-0\" tabindex=\"0\">Cytologic findings<\/a> <a href=\"#\" id=\"fl-accordion--icon-0\" tabindex=\"-1\"><i title=\"Expand\">Expand<\/i><\/a><\/p>\r\n<p>&nbsp;<\/p>\r\n<table>\r\n<tbody>\r\n<tr>\r\n<td><img decoding=\"async\" src=\"https:\/\/medicine.nus.edu.sg\/pathweb\/wp-content\/uploads\/2025\/06\/msk1.jpg\" alt=\"\" \/><\/td>\r\n<td><img decoding=\"async\" src=\"https:\/\/medicine.nus.edu.sg\/pathweb\/wp-content\/uploads\/2025\/06\/msk2.jpg\" alt=\"\" \/><\/td>\r\n<\/tr>\r\n<\/tbody>\r\n<\/table>\r\n<ul>\r\n<li>Dispersed cell pattern<\/li>\r\n<li>\r\n<ul>\r\n<li>Mostly mononuclear but may be multinucleated<\/li>\r\n<li><strong>Reniform nuclei with indents, folds and grooves (&#8220;coffee-bean&#8221;)<\/strong><\/li>\r\n<li>Abundant cytoplasm with occasional phagocytosed debris<\/li>\r\n<li>Distinct cell borders<\/li>\r\n<li>Mitoses may be present but no atypical forms\u00a0Scattered histiocytic cells with abundant cytoplasm<\/li>\r\n<li>No significant nuclear atypia<\/li>\r\n<\/ul>\r\n<\/li>\r\n<li>Associated with\u00a0<strong>numerous eosinophils\u00a0<\/strong>(red circles in the alcohol-fixed pic; hunt for them on the air-dried pic!)<\/li>\r\n<li>Occasional necrosis and osteoclast-type giant cells may be seen<\/li>\r\n<\/ul>\r\n<p><a href=\"#\" id=\"fl-accordion--label-1\" aria-controls=\"fl-accordion--panel-1\" tabindex=\"0\">DDx and Immunohistochemistry<\/a> <a href=\"#\" id=\"fl-accordion--icon-1\" tabindex=\"-1\"><i title=\"Expand\">Expand<\/i><\/a> \u00a0<br \/>Differentials to consider:<\/p>\r\n<ul>\r\n<li>Langerhans cell histiocytosis<\/li>\r\n<li>Acute and chronic osteomyelitis\r\n<ul>\r\n<li>Mixed inflammatory infiltrate and histiocytes<\/li>\r\n<li>Langerhans cells are not typically present<\/li>\r\n<\/ul>\r\n<\/li>\r\n<li>Granulomatous inflammation &#8211; no classical epithelioid histiocytes or well-formed granulomas<\/li>\r\n<\/ul>\r\n<p>Confirmatory immunohistochemistry:<\/p>\r\n<table>\r\n<tbody>\r\n<tr>\r\n<td><img decoding=\"async\" src=\"https:\/\/medicine.nus.edu.sg\/pathweb\/wp-content\/uploads\/2025\/06\/msk3.jpg\" alt=\"\" \/><\/td>\r\n<td><img decoding=\"async\" src=\"https:\/\/medicine.nus.edu.sg\/pathweb\/wp-content\/uploads\/2025\/06\/msk4.jpg\" alt=\"\" \/><\/td>\r\n<\/tr>\r\n<\/tbody>\r\n<\/table>\r\n<p>IHC interpretation:<\/p>\r\n<ul>\r\n<li>Positive stains: S100, CD1a and Langerin<\/li>\r\n<li>Stains to rule out differential diagnoses are usually not required<\/li>\r\n<\/ul>\r\n<p><a href=\"#\" id=\"fl-accordion--label-2\" aria-controls=\"fl-accordion--panel-2\" tabindex=\"0\">Diagnosis<\/a> <a href=\"#\" id=\"fl-accordion--icon-2\" tabindex=\"-1\"><i title=\"Expand\">Expand<\/i><\/a> \u00a0<br \/><strong>Langerhans cell histiocytosis<\/strong><\/p>\r\n<p><em>Case writer: Dr Noel Chia<\/em><\/p>\r\n","protected":false},"excerpt":{"rendered":"<p>Musculoskeletal 1 A groovy scapular lesion Clinical history: A 43-year-old lady presented with 3-month history of left shoulder pain. Plain film X-ray shows a well-defined lytic lesion in the left scapula. A CT-guided core biopsy of the lesion is performed and a cytology imprint is shown. Cytologic findings Expand &nbsp; Dispersed cell pattern Mostly mononuclear [&hellip;]<\/p>\n","protected":false},"author":828,"featured_media":0,"parent":44933,"menu_order":0,"comment_status":"closed","ping_status":"closed","template":"","meta":{"_acf_changed":false,"footnotes":""},"class_list":["post-45120","page","type-page","status-publish","hentry"],"acf":[],"yoast_head":"<!-- This site is optimized with the Yoast SEO plugin v25.4 - https:\/\/yoast.com\/wordpress\/plugins\/seo\/ -->\n<title>NUS Pathweb<\/title>\n<meta name=\"robots\" content=\"index, follow, max-snippet:-1, max-image-preview:large, max-video-preview:-1\" \/>\n<link rel=\"canonical\" href=\"https:\/\/medicine.nus.edu.sg\/pathweb\/cytopath\/cyto-mystery-cases\/msk-1\/\" \/>\n<meta property=\"og:locale\" content=\"en_US\" \/>\n<meta property=\"og:type\" content=\"article\" \/>\n<meta property=\"og:description\" content=\"Musculoskeletal 1 A groovy scapular lesion Clinical history: A 43-year-old lady presented with 3-month history of left shoulder pain. Plain film X-ray shows a well-defined lytic lesion in the left scapula. A CT-guided core biopsy of the lesion is performed and a cytology imprint is shown. Cytologic findings Expand &nbsp; Dispersed cell pattern Mostly mononuclear [&hellip;]\" \/>\n<meta property=\"og:url\" content=\"https:\/\/medicine.nus.edu.sg\/pathweb\/cytopath\/cyto-mystery-cases\/msk-1\/\" \/>\n<meta property=\"og:site_name\" content=\"NUS Pathweb\" \/>\n<meta property=\"article:modified_time\" content=\"2025-09-18T01:49:19+00:00\" \/>\n<meta property=\"og:image\" content=\"https:\/\/medicine.nus.edu.sg\/pathweb\/wp-content\/uploads\/2025\/06\/msk1.jpg\" \/>\n<meta name=\"twitter:card\" content=\"summary_large_image\" \/>\n<meta name=\"twitter:label1\" content=\"Est. reading time\" \/>\n\t<meta name=\"twitter:data1\" content=\"2 minutes\" \/>\n<script type=\"application\/ld+json\" class=\"yoast-schema-graph\">{\"@context\":\"https:\/\/schema.org\",\"@graph\":[{\"@type\":\"WebPage\",\"@id\":\"https:\/\/medicine.nus.edu.sg\/pathweb\/cytopath\/cyto-mystery-cases\/msk-1\/\",\"url\":\"https:\/\/medicine.nus.edu.sg\/pathweb\/cytopath\/cyto-mystery-cases\/msk-1\/\",\"name\":\"\",\"isPartOf\":{\"@id\":\"https:\/\/medicine.nus.edu.sg\/pathweb\/#website\"},\"primaryImageOfPage\":{\"@id\":\"https:\/\/medicine.nus.edu.sg\/pathweb\/cytopath\/cyto-mystery-cases\/msk-1\/#primaryimage\"},\"image\":{\"@id\":\"https:\/\/medicine.nus.edu.sg\/pathweb\/cytopath\/cyto-mystery-cases\/msk-1\/#primaryimage\"},\"thumbnailUrl\":\"https:\/\/medicine.nus.edu.sg\/pathweb\/wp-content\/uploads\/2025\/06\/msk1.jpg\",\"datePublished\":\"2025-08-05T06:04:50+00:00\",\"dateModified\":\"2025-09-18T01:49:19+00:00\",\"breadcrumb\":{\"@id\":\"https:\/\/medicine.nus.edu.sg\/pathweb\/cytopath\/cyto-mystery-cases\/msk-1\/#breadcrumb\"},\"inLanguage\":\"en-US\",\"potentialAction\":[{\"@type\":\"ReadAction\",\"target\":[\"https:\/\/medicine.nus.edu.sg\/pathweb\/cytopath\/cyto-mystery-cases\/msk-1\/\"]}]},{\"@type\":\"ImageObject\",\"inLanguage\":\"en-US\",\"@id\":\"https:\/\/medicine.nus.edu.sg\/pathweb\/cytopath\/cyto-mystery-cases\/msk-1\/#primaryimage\",\"url\":\"https:\/\/medicine.nus.edu.sg\/pathweb\/wp-content\/uploads\/2025\/06\/msk1.jpg\",\"contentUrl\":\"https:\/\/medicine.nus.edu.sg\/pathweb\/wp-content\/uploads\/2025\/06\/msk1.jpg\",\"width\":768,\"height\":576},{\"@type\":\"BreadcrumbList\",\"@id\":\"https:\/\/medicine.nus.edu.sg\/pathweb\/cytopath\/cyto-mystery-cases\/msk-1\/#breadcrumb\",\"itemListElement\":[{\"@type\":\"ListItem\",\"position\":1,\"name\":\"Home\",\"item\":\"https:\/\/medicine.nus.edu.sg\/pathweb\/\"},{\"@type\":\"ListItem\",\"position\":2,\"name\":\"Cytopathology\",\"item\":\"https:\/\/medicine.nus.edu.sg\/pathweb\/cytopath\/\"},{\"@type\":\"ListItem\",\"position\":3,\"name\":\"Cytopathology Mystery Cases\",\"item\":\"https:\/\/medicine.nus.edu.sg\/pathweb\/cytopath\/cyto-mystery-cases\/\"},{\"@type\":\"ListItem\",\"position\":4,\"name\":\"Mystery cases &#8211; Musculoskeletal 1\"}]},{\"@type\":\"WebSite\",\"@id\":\"https:\/\/medicine.nus.edu.sg\/pathweb\/#website\",\"url\":\"https:\/\/medicine.nus.edu.sg\/pathweb\/\",\"name\":\"NUS Pathweb\",\"description\":\"Pathology made easy\",\"publisher\":{\"@id\":\"https:\/\/medicine.nus.edu.sg\/pathweb\/#organization\"},\"potentialAction\":[{\"@type\":\"SearchAction\",\"target\":{\"@type\":\"EntryPoint\",\"urlTemplate\":\"https:\/\/medicine.nus.edu.sg\/pathweb\/?s={search_term_string}\"},\"query-input\":{\"@type\":\"PropertyValueSpecification\",\"valueRequired\":true,\"valueName\":\"search_term_string\"}}],\"inLanguage\":\"en-US\"},{\"@type\":\"Organization\",\"@id\":\"https:\/\/medicine.nus.edu.sg\/pathweb\/#organization\",\"name\":\"NUS Medicine PathWeb\",\"url\":\"https:\/\/medicine.nus.edu.sg\/pathweb\/\",\"logo\":{\"@type\":\"ImageObject\",\"inLanguage\":\"en-US\",\"@id\":\"https:\/\/medicine.nus.edu.sg\/pathweb\/#\/schema\/logo\/image\/\",\"url\":\"https:\/\/medicine.nus.edu.sg\/pathweb\/wp-content\/uploads\/2020\/08\/NUS-Medicine-Logo.png\",\"contentUrl\":\"https:\/\/medicine.nus.edu.sg\/pathweb\/wp-content\/uploads\/2020\/08\/NUS-Medicine-Logo.png\",\"width\":300,\"height\":61,\"caption\":\"NUS Medicine PathWeb\"},\"image\":{\"@id\":\"https:\/\/medicine.nus.edu.sg\/pathweb\/#\/schema\/logo\/image\/\"},\"sameAs\":[\"https:\/\/www.instagram.com\/pathweb\/\",\"https:\/\/www.youtube.com\/channel\/UC3FweZwONWAicB72vF9P5ew\/playlists\"]}]}<\/script>\n<!-- \/ Yoast SEO plugin. -->","yoast_head_json":{"title":"NUS Pathweb","robots":{"index":"index","follow":"follow","max-snippet":"max-snippet:-1","max-image-preview":"max-image-preview:large","max-video-preview":"max-video-preview:-1"},"canonical":"https:\/\/medicine.nus.edu.sg\/pathweb\/cytopath\/cyto-mystery-cases\/msk-1\/","og_locale":"en_US","og_type":"article","og_description":"Musculoskeletal 1 A groovy scapular lesion Clinical history: A 43-year-old lady presented with 3-month history of left shoulder pain. Plain film X-ray shows a well-defined lytic lesion in the left scapula. A CT-guided core biopsy of the lesion is performed and a cytology imprint is shown. Cytologic findings Expand &nbsp; Dispersed cell pattern Mostly mononuclear [&hellip;]","og_url":"https:\/\/medicine.nus.edu.sg\/pathweb\/cytopath\/cyto-mystery-cases\/msk-1\/","og_site_name":"NUS Pathweb","article_modified_time":"2025-09-18T01:49:19+00:00","og_image":[{"url":"https:\/\/medicine.nus.edu.sg\/pathweb\/wp-content\/uploads\/2025\/06\/msk1.jpg","type":"","width":"","height":""}],"twitter_card":"summary_large_image","twitter_misc":{"Est. reading time":"2 minutes"},"schema":{"@context":"https:\/\/schema.org","@graph":[{"@type":"WebPage","@id":"https:\/\/medicine.nus.edu.sg\/pathweb\/cytopath\/cyto-mystery-cases\/msk-1\/","url":"https:\/\/medicine.nus.edu.sg\/pathweb\/cytopath\/cyto-mystery-cases\/msk-1\/","name":"","isPartOf":{"@id":"https:\/\/medicine.nus.edu.sg\/pathweb\/#website"},"primaryImageOfPage":{"@id":"https:\/\/medicine.nus.edu.sg\/pathweb\/cytopath\/cyto-mystery-cases\/msk-1\/#primaryimage"},"image":{"@id":"https:\/\/medicine.nus.edu.sg\/pathweb\/cytopath\/cyto-mystery-cases\/msk-1\/#primaryimage"},"thumbnailUrl":"https:\/\/medicine.nus.edu.sg\/pathweb\/wp-content\/uploads\/2025\/06\/msk1.jpg","datePublished":"2025-08-05T06:04:50+00:00","dateModified":"2025-09-18T01:49:19+00:00","breadcrumb":{"@id":"https:\/\/medicine.nus.edu.sg\/pathweb\/cytopath\/cyto-mystery-cases\/msk-1\/#breadcrumb"},"inLanguage":"en-US","potentialAction":[{"@type":"ReadAction","target":["https:\/\/medicine.nus.edu.sg\/pathweb\/cytopath\/cyto-mystery-cases\/msk-1\/"]}]},{"@type":"ImageObject","inLanguage":"en-US","@id":"https:\/\/medicine.nus.edu.sg\/pathweb\/cytopath\/cyto-mystery-cases\/msk-1\/#primaryimage","url":"https:\/\/medicine.nus.edu.sg\/pathweb\/wp-content\/uploads\/2025\/06\/msk1.jpg","contentUrl":"https:\/\/medicine.nus.edu.sg\/pathweb\/wp-content\/uploads\/2025\/06\/msk1.jpg","width":768,"height":576},{"@type":"BreadcrumbList","@id":"https:\/\/medicine.nus.edu.sg\/pathweb\/cytopath\/cyto-mystery-cases\/msk-1\/#breadcrumb","itemListElement":[{"@type":"ListItem","position":1,"name":"Home","item":"https:\/\/medicine.nus.edu.sg\/pathweb\/"},{"@type":"ListItem","position":2,"name":"Cytopathology","item":"https:\/\/medicine.nus.edu.sg\/pathweb\/cytopath\/"},{"@type":"ListItem","position":3,"name":"Cytopathology Mystery Cases","item":"https:\/\/medicine.nus.edu.sg\/pathweb\/cytopath\/cyto-mystery-cases\/"},{"@type":"ListItem","position":4,"name":"Mystery cases &#8211; Musculoskeletal 1"}]},{"@type":"WebSite","@id":"https:\/\/medicine.nus.edu.sg\/pathweb\/#website","url":"https:\/\/medicine.nus.edu.sg\/pathweb\/","name":"NUS Pathweb","description":"Pathology made easy","publisher":{"@id":"https:\/\/medicine.nus.edu.sg\/pathweb\/#organization"},"potentialAction":[{"@type":"SearchAction","target":{"@type":"EntryPoint","urlTemplate":"https:\/\/medicine.nus.edu.sg\/pathweb\/?s={search_term_string}"},"query-input":{"@type":"PropertyValueSpecification","valueRequired":true,"valueName":"search_term_string"}}],"inLanguage":"en-US"},{"@type":"Organization","@id":"https:\/\/medicine.nus.edu.sg\/pathweb\/#organization","name":"NUS Medicine PathWeb","url":"https:\/\/medicine.nus.edu.sg\/pathweb\/","logo":{"@type":"ImageObject","inLanguage":"en-US","@id":"https:\/\/medicine.nus.edu.sg\/pathweb\/#\/schema\/logo\/image\/","url":"https:\/\/medicine.nus.edu.sg\/pathweb\/wp-content\/uploads\/2020\/08\/NUS-Medicine-Logo.png","contentUrl":"https:\/\/medicine.nus.edu.sg\/pathweb\/wp-content\/uploads\/2020\/08\/NUS-Medicine-Logo.png","width":300,"height":61,"caption":"NUS Medicine PathWeb"},"image":{"@id":"https:\/\/medicine.nus.edu.sg\/pathweb\/#\/schema\/logo\/image\/"},"sameAs":["https:\/\/www.instagram.com\/pathweb\/","https:\/\/www.youtube.com\/channel\/UC3FweZwONWAicB72vF9P5ew\/playlists"]}]}},"_links":{"self":[{"href":"https:\/\/medicine.nus.edu.sg\/pathweb\/wp-json\/wp\/v2\/pages\/45120"}],"collection":[{"href":"https:\/\/medicine.nus.edu.sg\/pathweb\/wp-json\/wp\/v2\/pages"}],"about":[{"href":"https:\/\/medicine.nus.edu.sg\/pathweb\/wp-json\/wp\/v2\/types\/page"}],"author":[{"embeddable":true,"href":"https:\/\/medicine.nus.edu.sg\/pathweb\/wp-json\/wp\/v2\/users\/828"}],"replies":[{"embeddable":true,"href":"https:\/\/medicine.nus.edu.sg\/pathweb\/wp-json\/wp\/v2\/comments?post=45120"}],"version-history":[{"count":7,"href":"https:\/\/medicine.nus.edu.sg\/pathweb\/wp-json\/wp\/v2\/pages\/45120\/revisions"}],"predecessor-version":[{"id":45690,"href":"https:\/\/medicine.nus.edu.sg\/pathweb\/wp-json\/wp\/v2\/pages\/45120\/revisions\/45690"}],"up":[{"embeddable":true,"href":"https:\/\/medicine.nus.edu.sg\/pathweb\/wp-json\/wp\/v2\/pages\/44933"}],"wp:attachment":[{"href":"https:\/\/medicine.nus.edu.sg\/pathweb\/wp-json\/wp\/v2\/media?parent=45120"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}