{"id":4465,"date":"2022-05-03T11:47:20","date_gmt":"2022-05-03T10:47:20","guid":{"rendered":"https:\/\/apps.nhslothian.scot\/refhelp\/guidelines\/thrombocytosis\/"},"modified":"2026-03-30T15:53:38","modified_gmt":"2026-03-30T14:53:38","slug":"thrombocytosis","status":"publish","type":"page","link":"https:\/\/apps.nhslothian.scot\/refhelp\/guidelines\/haematology\/thrombocytosis\/","title":{"rendered":"Thrombocytosis"},"content":{"rendered":"\n<h4 class=\"wp-block-heading\"><strong>Definition<\/strong><\/h4>\n\n\n\n<p>Persistent significant increase in platelet count &gt;450\u00d710<sup>9<\/sup>\/L. Reactive causes are much more common than myeloproliferative neoplasms (MPNs).<\/p>\n\n\n\n<p><strong><u>Causes<\/u><\/strong>.<\/p>\n\n\n\n<ul class=\"wp-block-list\">\n<li>Primary causes can be associated with an associated erythrocytosis or leucocytosis. Haematological conditions associated with a raised platelet count including essential thrombocythaemia, polycythaemia vera, primary myelofibrosis, chronic myeloid leukaemia, myelodysplastic syndromes, and unclassified myeloproliferative disorders. Complications of MPNs include arterial or venous occlusive events.<\/li>\n\n\n\n<li>Reactive thrombocytosis (commonest cause): infection; inflammation; iron deficiency and\/or bleeding; recent surgery; hyposplenism; solid organ malignancy.<\/li>\n<\/ul>\n\n\n\n<p><mark style=\"background-color:#ffffff\" class=\"has-inline-color has-alert-red-color\"><span style=\"text-decoration: underline\"><strong>THROMBOCYTOSIS &amp; CANCER &#8211; the \u2018LEGO-C\u2019 group.<\/strong><\/span><\/mark><\/p>\n\n\n\n<p><mark style=\"background-color:#ffffff\" class=\"has-inline-color has-alert-red-color\"><strong>Thrombocytosis is a risk marker for malignancy. This especially applies to the \u2018LEGO-C\u2019 group \u2013<span style=\"text-decoration: underline\">Lung, Endometrial, Gastric, Oesophageal and Colorectal cancer.<\/span><\/strong><\/mark><\/p>\n\n\n\n<p><strong><mark style=\"background-color:#ffffff\" class=\"has-inline-color has-alert-red-color\">The<\/mark> <\/strong><a href=\"https:\/\/www.gov.scot\/binaries\/content\/documents\/govscot\/publications\/advice-and-guidance\/2025\/08\/scottish-referral-guidelines-suspected-cancer-2025\/documents\/scottish-referral-guidelines-suspected-cancer-2025\/scottish-referral-guidelines-suspected-cancer-2025\/govscot%3Adocument\/scottish-referral-guidelines-suspected-cancer-2025.pdf\" target=\"_blank\" rel=\"noreferrer noopener\">Scottish Referral Guidelines for Suspected Cancer 2025<\/a><strong> <mark style=\"background-color:#ffffff\" class=\"has-inline-color has-alert-red-color\">report <span style=\"text-decoration: underline\">higher all-cancer incidence in those aged \u226540 with new thrombocytosis (platelets&gt;400 x 109 \/L)<\/span>. The incidence is 11.6% in men and 6.2% in women (cf controls of 4.1% \/ 2.2% respectively), well exceeding the threshold for referral for malignancy.<\/mark><\/strong><\/p>\n\n\n\n<p><strong><span style=\"text-decoration: underline\"><mark style=\"background-color:#ffffff\" class=\"has-inline-color has-alert-red-color\">For all those with an unexplained thrombocytosis, consider whether there might be associated malignancy:<\/mark><\/span><\/strong><\/p>\n\n\n\n<ul class=\"wp-block-list\">\n<li><mark style=\"background-color:#ffffff\" class=\"has-inline-color has-alert-red-color\"><strong>Patient history and examination, in particular considering the LEGO-C cancers: <em>lung, endometrial, gastric, oesophageal and colorectal.<\/em><\/strong><\/mark><\/li>\n\n\n\n<li><strong><mark style=\"background-color:#ffffff\" class=\"has-inline-color has-alert-red-color\">where there are no tumour-specific symptoms arrange a USC chest X-ray.<\/mark><\/strong><\/li>\n\n\n\n<li><strong><mark style=\"background-color:#ffffff\" class=\"has-inline-color has-alert-red-color\">when combined with non-specific symptoms such as significant weight loss or GP \u2018gut feeling\u2019, <span style=\"text-decoration: underline\">consider referral for further cancer investigation <\/span>eg GP direct access to imaging pathway \/ see the<\/mark> <\/strong><a href=\"https:\/\/www.gov.scot\/binaries\/content\/documents\/govscot\/publications\/advice-and-guidance\/2025\/08\/scottish-referral-guidelines-suspected-cancer-2025\/documents\/scottish-referral-guidelines-suspected-cancer-2025\/scottish-referral-guidelines-suspected-cancer-2025\/govscot%3Adocument\/scottish-referral-guidelines-suspected-cancer-2025.pdf\" target=\"_blank\" rel=\"noreferrer noopener\">Scottish Referral Guidelines for Suspected Cancer 2025<\/a><\/li>\n\n\n\n<li><mark style=\"background-color:#ffffff\" class=\"has-inline-color has-alert-red-color\"><strong>This process will often diagnose or exclude the possibility of a reactive thrombocytosis.<\/strong><\/mark><\/li>\n<\/ul>\n\n\n\n<p><mark style=\"background-color:#ffffff\" class=\"has-inline-color has-alert-red-color\"><strong>Thrombocytosis occurring with an elevated alkaline phosphatase (ALP), has a yet-higher PPV for cancer.<\/strong><\/mark><\/p>\n\n\n\n<p><strong><em>Please see Primary Care Management for more detail including initial investigation.<\/em><\/strong><\/p>\n\n\n\n<p><strong>IK, KD &amp; CM 2\/12\/25<\/strong><\/p>\n\n\n\n<div class=\"wp-block-getwid-tabs\" data-active-tab=\"0\"><ul class=\"wp-block-getwid-tabs__nav-links\"><\/ul>\n<div class=\"wp-block-getwid-tabs__nav-link\"><span class=\"wp-block-getwid-tabs__title-wrapper\"><a href=\"#\"><span class=\"wp-block-getwid-tabs__title\">Referral Guidelines<\/span><\/a><\/span><\/div><div class=\"wp-block-getwid-tabs__tab-content-wrapper\"><div class=\"wp-block-getwid-tabs__tab-content\">\n<h4 class=\"wp-block-heading\">Who to refer:<\/h4>\n\n\n\n<ul class=\"wp-block-list\">\n<li><strong><span style=\"text-decoration: underline\"><mark style=\"background-color:#ffffff\" class=\"has-inline-color has-alert-red-color\">Consider LEGO-C cancers and if suspicious features, please refer to the relevant specialty.<\/mark><\/span><\/strong><\/li>\n\n\n\n<li>Any patient with a persistent unexplained thrombocytosis of &gt;450 x 10<sup>9<\/sup>\/L for at least 3 months.&nbsp; OR<\/li>\n\n\n\n<li>Patients with an acute arterial or venous occlusive event and a platelet count &gt;450\u00d710<sup>9<\/sup>\/L.<\/li>\n<\/ul>\n\n\n\n<h4 class=\"wp-block-heading\">Who not to refer:<\/h4>\n\n\n\n<p>Patients without persistent thrombocytosis or those with evidence of an underlying cause for a reactive thrombocytosis; and where relevant an associated cancer diagnosis has been considered \/ excluded.<\/p>\n\n\n\n<h4 class=\"wp-block-heading\">How to refer:<\/h4>\n\n\n\n<p>SCI Gateway to Department of Haematology WGH or St John\u2019s Hospital.<\/p>\n<\/div><\/div>\n\n\n\n<div class=\"wp-block-getwid-tabs__nav-link\"><span class=\"wp-block-getwid-tabs__title-wrapper\"><a href=\"#\"><span class=\"wp-block-getwid-tabs__title\">Primary Care Management<\/span><\/a><\/span><\/div><div class=\"wp-block-getwid-tabs__tab-content-wrapper\"><div class=\"wp-block-getwid-tabs__tab-content\">\n<p><strong><span style=\"text-decoration: underline\"><mark style=\"background-color:#ffffff\" class=\"has-inline-color has-alert-red-color\">For all those with an unexplained thrombocytosis, consider whether there might be associated malignancy:<\/mark><\/span><\/strong><\/p>\n\n\n\n<ul class=\"wp-block-list\">\n<li><mark style=\"background-color:#ffffff\" class=\"has-inline-color has-alert-red-color\"><strong>Patient history and examination, in particular considering the LEGO-C cancers: <em>lung, endometrial, gastric, oesophageal and colorectal.<\/em><\/strong><\/mark><\/li>\n\n\n\n<li><strong><mark style=\"background-color:#ffffff\" class=\"has-inline-color has-alert-red-color\">where there are no tumour-specific symptoms arrange a USC chest X-ray.<\/mark><\/strong><\/li>\n\n\n\n<li><strong><mark style=\"background-color:#ffffff\" class=\"has-inline-color has-alert-red-color\">when combined with non-specific symptoms such as significant weight loss or GP \u2018gut feeling\u2019, <span style=\"text-decoration: underline\">consider referral for further cancer investigation <\/span>eg GP direct access to imaging pathway \/ see the<\/mark> <a href=\"https:\/\/www.gov.scot\/binaries\/content\/documents\/govscot\/publications\/advice-and-guidance\/2025\/08\/scottish-referral-guidelines-suspected-cancer-2025\/documents\/scottish-referral-guidelines-suspected-cancer-2025\/scottish-referral-guidelines-suspected-cancer-2025\/govscot%3Adocument\/scottish-referral-guidelines-suspected-cancer-2025.pdf\" target=\"_blank\" rel=\"noreferrer noopener\">Scottish Referral Guidelines for Suspected Cancer<\/a><\/strong><\/li>\n\n\n\n<li><mark style=\"background-color:#ffffff\" class=\"has-inline-color has-alert-red-color\"><strong>This process will often diagnose or exclude the possibility of a reactive thrombocytosis.<\/strong><\/mark><\/li>\n<\/ul>\n\n\n\n<p><strong><u>Please also consider<\/u><\/strong><\/p>\n\n\n\n<ul class=\"wp-block-list\">\n<li>The differential diagnosis of thrombocytosis is wide and most commonly secondary to non-haematological causes. <em>Look for and treat reactive causes prior to referral<\/em><\/li>\n\n\n\n<li>Serial FBCs; blood film; CRP and ESR; ferritin, C&amp;Es, LFTs, LDH<\/li>\n\n\n\n<li>Significant reactive thrombocytosis can take 4-8 weeks to return to baseline<\/li>\n<\/ul>\n\n\n\n<ul class=\"wp-block-list\">\n<li>Thrombocytosis associated with chronic inflammatory conditions may not resolve.<\/li>\n<\/ul>\n<\/div><\/div>\n\n\n\n<div class=\"wp-block-getwid-tabs__nav-link\"><span class=\"wp-block-getwid-tabs__title-wrapper\"><a href=\"#\"><span class=\"wp-block-getwid-tabs__title\">Resources and Links<\/span><\/a><\/span><\/div><div class=\"wp-block-getwid-tabs__tab-content-wrapper\"><div class=\"wp-block-getwid-tabs__tab-content\">\n<ul class=\"wp-block-list\">\n<li><a href=\"https:\/\/bjgp.org\/content\/67\/659\/e405\" target=\"_blank\" rel=\"noreferrer noopener\">Clinical relevance of thrombocytosis in primary care: a prospective cohort study of cancer incidence using English electronic medical records and cancer registry data | British Journal of General Practice<\/a><\/li>\n\n\n\n<li><a href=\"https:\/\/www.gov.scot\/binaries\/content\/documents\/govscot\/publications\/advice-and-guidance\/2025\/08\/scottish-referral-guidelines-suspected-cancer-2025\/documents\/scottish-referral-guidelines-suspected-cancer-2025\/scottish-referral-guidelines-suspected-cancer-2025\/govscot%3Adocument\/scottish-referral-guidelines-suspected-cancer-2025.pdf\" target=\"_blank\" rel=\"noreferrer noopener\">Scottish Referral Guidelines for Suspected Cancer<\/a><\/li>\n<\/ul>\n<\/div><\/div>\n<\/div>\n","protected":false},"excerpt":{"rendered":"<p>Definition Persistent significant increase in platelet count &gt;450&times;109\/L. Reactive causes are much more common than myeloproliferative neoplasms (MPNs). Causes. THROMBOCYTOSIS &amp; CANCER &ndash; the &lsquo;LEGO-C&rsquo; group. Thrombocytosis is a risk marker for malignancy. This especially applies to the &lsquo;LEGO-C&rsquo; group &ndash;Lung, Endometrial, Gastric, Oesophageal and Colorectal cancer. The Scottish Referral Guidelines for Suspected Cancer 2025<\/p>\n","protected":false},"author":2,"featured_media":0,"parent":3981,"menu_order":0,"comment_status":"closed","ping_status":"closed","template":"","meta":{"footnotes":""},"categories":[276],"class_list":["post-4465","page","type-page","status-publish","hentry","category-thrombocytosis"],"publishpress_future_workflow_manual_trigger":{"enabledWorkflows":[]},"rttpg_featured_image_url":null,"rttpg_author":{"display_name":"NHS Lothian","author_link":"https:\/\/apps.nhslothian.scot\/refhelp\/author\/nhs-lothian\/"},"rttpg_comment":0,"rttpg_category":" <a href=\"https:\/\/apps.nhslothian.scot\/refhelp\/category\/haematology\/thrombocytosis\/\" rel=\"tag\">Thrombocytosis<\/a>","rttpg_excerpt":"Definition Persistent significant increase in platelet count &gt;450&times;109\/L. Reactive causes are much more common than myeloproliferative neoplasms (MPNs). Causes. THROMBOCYTOSIS &amp; CANCER &ndash; the &lsquo;LEGO-C&rsquo; group. Thrombocytosis is a risk marker for malignancy. This especially applies to the &lsquo;LEGO-C&rsquo; group &ndash;Lung, Endometrial, Gastric, Oesophageal and Colorectal cancer. The Scottish Referral Guidelines for Suspected Cancer 2025","_links":{"self":[{"href":"https:\/\/apps.nhslothian.scot\/refhelp\/wp-json\/wp\/v2\/pages\/4465","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/apps.nhslothian.scot\/refhelp\/wp-json\/wp\/v2\/pages"}],"about":[{"href":"https:\/\/apps.nhslothian.scot\/refhelp\/wp-json\/wp\/v2\/types\/page"}],"author":[{"embeddable":true,"href":"https:\/\/apps.nhslothian.scot\/refhelp\/wp-json\/wp\/v2\/users\/2"}],"replies":[{"embeddable":true,"href":"https:\/\/apps.nhslothian.scot\/refhelp\/wp-json\/wp\/v2\/comments?post=4465"}],"version-history":[{"count":18,"href":"https:\/\/apps.nhslothian.scot\/refhelp\/wp-json\/wp\/v2\/pages\/4465\/revisions"}],"predecessor-version":[{"id":27474,"href":"https:\/\/apps.nhslothian.scot\/refhelp\/wp-json\/wp\/v2\/pages\/4465\/revisions\/27474"}],"up":[{"embeddable":true,"href":"https:\/\/apps.nhslothian.scot\/refhelp\/wp-json\/wp\/v2\/pages\/3981"}],"wp:attachment":[{"href":"https:\/\/apps.nhslothian.scot\/refhelp\/wp-json\/wp\/v2\/media?parent=4465"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/apps.nhslothian.scot\/refhelp\/wp-json\/wp\/v2\/categories?post=4465"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}