Cancer Assciatin f Suth Africa (CANSA) Fact Sheet n Essential Thrmbcythaemia Intrductin Essential thrmbcythaemia (ET) is nt a type f bld cancer as there are n cancerus cells. It is cnsidered a chrnic haematlgical malignancy and is smetimes referred t as a pre-leukaemic disrder which means that it may eventually cause ne r ther type f leukaemia. ET can result frm a mutatin in bld-frming stem cells, which causes bld cells (particularly platelets) t prduce uncntrllably. Hwever, research is still being dne t understand the additinal causes f ET. It is ne f the knwn myelprliferative neplasms (MPNs). Certain myelprliferative neplasms may becme acute myelid leukaemia (AML). Myelprliferative neplasms include chrnic myelgenus leukemia (CML), plycythaemia vera, primary myelfibrsis, essential thrmbcythaemia, chrnic neutrphilic leukaemia, and chrnic esinphilic leukaemia. Als called chrnic myelprliferative neplasm. The main types f MPN are: essential thrmbcythaemia plycythaemia vera myelfibrsis. [Picture Credit: Essential Thrmbcythaemia] ET is als knwn as essential thrmbcytsis, thrmbcytsis, and primary thrmbcytsis. Sme peple with essential thrmbcythaemia develp myelfibrsis. This is a cnditin in which the bne marrw becmes scarred. Peple with MPNs rarely develp leukaemia. (Cancer Supprt Cmmunity; Myelprliferative Disrder Research Cnsrtium). T understand ET ne must knw abut the rle f bne marrw. Bne marrw is part f the immune system, which prtects man frm infectin and disease. The marrw is in the spngy material fund inside bnes. This is where stem cells are made. Stem cells are bld Researched and Authred by Prf Michael C Herbst [D Litt et Phil (Health Studies); D N Ed; M Art et Scien; B A Cur; Dip Occupatinal Health] Apprved fr Distributin by Ms Elize Jubert, Acting CEO December 2014 Page 1
cells at their earliest stage f develpment. All bld cells grw frm stem cells. The three main types f bld cells are: red bld cells which carry xygen arund the bdy white bld cells which fight infectins platelets which help bld t clt t prevent bleeding. The bne marrw makes millins f bld cells every day. When the cells are mature they are released int the bld stream. In MPNs, the bne marrw makes t many f ne r mre types f bld cells (Macmillan Cancer Supprt). Incidence f Essential Thrmbcythaemia in Suth Africa The Natinal Cancer Registry (2008) des nt prvide any infrmatin regarding the incidence f Essential Thrmbcythaemia in Suth Africa. Causes f Essential Thrmbcythaemia (ET) The causes f ET are still unknwn. Abut half f ET patients have a mutatin called JAK2V617F within the bld-frming cells, which leads t many characteristic features f the disease. Sme risk factrs assciated with ET include: Gender - wmen are 1.5 times mre likely than men t develp the cnditin Age - peple lder than 60 are mst likely t develp the cnditin, althugh 20 percent f thse affected are yunger than 40 Envirnment - expsure t chemicals r t electrical wiring may increase an individual's risk fr the cnditin In all f the myelprliferative disrders, a stem cell that is capable f prducing red bld cells, certain white cells and platelets smehw ges haywire and n lnger keeps the bld elements prduced by the marrw in balance. In essential thrmbcythaemia, the marrw prduces t many platelets. (Jhns Hpkins Medicine; Myelprliferative Disrder Research Cnsrtium). Symptms f Essential Thrmbcythaemia (ET) Many patients d nt have any symptms. The diagnsis is ften made after bld cunts were dne as part f a rutine check-up which then reveals a high platelet cunt. Symptms, if present, include fatigue, r bld vessel disturbances r bleeding. Bld vessel disturbances r bleeding can result in: Headache Visin disturbances r silent migraines Dizziness r lightheadedness Fainting Cldness r blueness f fingers r tes Burning, redness, and pain r numbness in the hands and feet Researched and Authred by Prf Michael C Herbst [D Litt et Phil (Health Studies); D N Ed; M Art et Scien; B A Cur; Dip Occupatinal Health] Apprved fr Distributin by Ms Elize Jubert, Acting CEO December 2014 Page 2
Redness, thrbbing and burning pain in the hands and feet (erythrmelalgia) Mildly enlarged spleen Difficulty speaking r understanding speech (aphasia) Blurred, duble r decreased visin Easy bruising, nsebleeds r heavy perids Gastrintestinal bleeding r bld in the urine Erythrmelalgia is a rare and frequently devastating disrder that typically affects the skin f the feet r hands, r bth, and causes visible redness, intense heat and burning pain. It usually affects the lwer extremities (legs and feet) and upper extremities (arms and hands) including ther bdy parts like the face, ear r nse. It usually affects bth sides f the bdy, but has been knwn t nly affect ne side. The assciatin f pain and burning sensatins can be extremely severe. (Jhns Hpkins Medicine; May Clinic; Erythrmelalgia Assciatin). There are als ther metablic abnrmalities fund in patients with myelprliferative neplasms. These include: Elevated uric acid cunts are seen in abut half f MPN patients during the curse f their disease. If untreated, this leads t uric acid stnes, uric acid neurpathy, acute gut, and chrnic guty arthritis. Patients may experience jint pain as a result Lw chlesterl levels (hypchlestraemia), particularly in thse with enlarged spleens (splenmegaly) Elevated histamine levels. Symptms f increased histamine release include pruritis (itching characteristically prduced by bathing r shwering), heartburn, acid eructatin (gas), peptic ulcer, small bwel hypermtility, flushing and angineurtic edema (swelling f skin, mucus membranes r viscera). This ccurs in 2/3rds f myelprliferative disrder patients and crrelates with presence f elevated basphil cunt and hyperhistaminaemia Hypermetablism which cmmnly manifests as weakness and fatigue in the absence f anaemia (Myelprliferative Disrder Research Cnsrtium). Cmplicatins f Essential Thrmbcythaemia (ET) The abnrmal bld cltting f essential thrmbcythaemia can lead t a variety f ptentially serius cmplicatins, including: Pregnancy cmplicatins. While many wmen wh have thrmbcythaemia have nrmal, healthy pregnancies, they must ensure that their dctr regularly mnitrs their cnditin. Uncntrlled thrmbcythaemia may cause miscarriage, premature delivery, high bld pressure (preeclampsia), early separatin f the placenta frm the uterine wall (placental abruptin) and slw fetal grwth. The risk f cmplicatins may be reduced with regular checkups and medicatin Strke. A clt that blcks bld flw t the brain can cause a strke. If smene develps signs and symptms f a strke, get immediate medical attentin Researched and Authred by Prf Michael C Herbst [D Litt et Phil (Health Studies); D N Ed; M Art et Scien; B A Cur; Dip Occupatinal Health] Apprved fr Distributin by Ms Elize Jubert, Acting CEO December 2014 Page 3
Heart attack. A clt that bstructs bld flw t the heart can cause a heart attack. If smene develp signs and symptms f a heart attack, such as pressure, fullness r a squeezing pain in the centre f the chest lasting mre than a few minutes; pain extending t the shulder, arm, back, teeth r jaw; shrtness f breath; and sweating r clammy skin, get immediate medical attentin Essential thrmbcythaemia can als cause bleeding (haemrrhage) with significant bld lss. A small minrity f peple with essential thrmbcythaemia may later develp acute leukaemia r myelfibrsis, bth f which can be life-threatening: Acute leukaemia. Acute myelgenus leukaemia is a type f bld and bne marrw cancer that prgresses rapidly Myelfibrsis. This prgressive bne marrw disrder results in bne marrw scarring, severe anaemia, and enlargement f yur liver and spleen (May Clinic). Treatment f Essential Thrmbcythaemia (ET) ET is treated based n the persn s risk f cmplicatins, such as bleeding and bld cltting. Peple with n signs r symptms ther than an increased platelet cunt have a lwer risk f cmplicatins. These peple, especially thse with n ther cardivascular risk factrs, may nly need regular check-ups. Peple at high risk fr bleeding and cltting cmplicatins need treatment. Risks fr cltting cmplicatins include: previus clt cardivascular risk factrs high chlesterl, diabetes, smking, besity r high bld pressure Risks fr bleeding cmplicatins include: extremely high platelet cunt regular use f standard-dse aspirin r nn-steridal anti-inflammatry drugs (Canadian Cancer Sciety). Medical Disclaimer This Fact Sheet is intended t prvide general infrmatin nly and, as such, shuld nt be cnsidered as a substitute fr advice, medically r therwise, cvering any specific situatin. Users shuld seek apprpriate advice befre taking r refraining frm taking any actin in reliance n any infrmatin cntained in this Fact Sheet. S far as permissible by law, the Cancer Assciatin f Suth Africa (CANSA) des nt accept any liability t any persn (r his/her dependants/estate/heirs) relating t the use f any infrmatin cntained in this Fact Sheet. Whilst the Cancer Assciatin f Suth Africa (CANSA) has taken every precautin in cmpiling this Fact Sheet, neither it, nr any cntributr(s) t this Fact Sheet can be held respnsible fr any actin (r the lack theref) taken by any persn r rganisatin wherever Researched and Authred by Prf Michael C Herbst [D Litt et Phil (Health Studies); D N Ed; M Art et Scien; B A Cur; Dip Occupatinal Health] Apprved fr Distributin by Ms Elize Jubert, Acting CEO December 2014 Page 4
they shall be based, as a result, direct r therwise, f infrmatin cntained in, r accessed thrugh, this Fact Sheet. Researched and Authred by Prf Michael C Herbst [D Litt et Phil (Health Studies); D N Ed; M Art et Scien; B A Cur; Dip Occupatinal Health] Apprved fr Distributin by Ms Elize Jubert, Acting CEO December 2014 Page 5
Surces and References Canadian Cancer Sciety http://www.cancer.ca/en/cancer-infrmatin/cancer-type/leukemia/pathlgy-andstaging/essential-thrmbcythemia/?regin=n Cancer Supprt Cmmunity http://www.cancersupprtcmmunity.rg/mainmenu/abut-cancer/types-f- Cancer/Myelprliferative-Neplasms-2/What-is-Essential-thrmbcythemia-ET.html Erythrmelalgia Asscatin http://www.erythrmelalgia.rg/whatisem.aspx Essential Thrmbcythaemia https://www.ggle.c.za/search?q=essential+thrmbcythemia+cancer&surce=lnms&tbm =isch&sa=x&ei=ssyu5r8ujsbqagfgg&sqi=2&ved=0cayq_auaq&biw=1517&bih=71 4&dpr=0.9#facrc=_&imgdii=_&imgrc=J7h5nTaOV-c- TM%253A%3BxT2sEFx81lriCM%3Bhttp%253A%252F%252Fstatic.cdnseekingalpha.cm%252Fuplads%252F2014%252F1%252F834108_13906209951263_rId8.jpg%3Bhttp%253A%252F%252Fseekingalpha.cm%252Farticle%252F1971101-theacquisitin-f-mills-pharmaceuticals-put-anther-arrw-in-the-quiver-fgalena%3B544%3B319 Jhns Hpkins Medicine http://www.hpkinsmedicine.rg/kimmel_cancer_center/centers/bne_marrw_failure_disrd ers/essential_thrmbcytsis.html MacMillan Cancer Supprt http://www.macmillan.rg.uk/cancerinfrmatin/causesriskfactrs/precancerus/essentialthrmbcythaemia.aspx May Clinic http://www.mayclinic.rg/diseases-cnditins/thrmbcythemia/basics/symptms/cn- 20034386 http://www.mayclinic.rg/diseases-cnditins/thrmbcythemia/basics/cmplicatins/cn- 20034386 Myelprliferative Disrder Research Cnsrtium http://www.mpd-rc.rg/faq.php?cat_id=4 Researched and Authred by Prf Michael C Herbst [D Litt et Phil (Health Studies); D N Ed; M Art et Scien; B A Cur; Dip Occupatinal Health] Apprved fr Distributin by Ms Elize Jubert, Acting CEO December 2014 Page 6