▁LE MS ▁is ▁diagn osed , ▁investig ations ▁such ▁as ▁a ▁CT ▁scan ▁of ▁the ▁ch est ▁are ▁usually ▁performed ▁to ▁identify ▁any ▁possible ▁underlying ▁lung ▁tum ors . ▁Ar ound ▁ 5 0 – 6 0 % ▁of ▁these ▁are ▁discovered ▁immediately ▁after ▁the ▁diagn osis ▁of ▁LE MS . ▁The ▁remainder ▁is ▁diagn osed ▁later , ▁but ▁usually ▁within ▁two ▁years ▁and ▁typically ▁within ▁four ▁years . ▁As ▁a ▁result , ▁sc ans ▁are ▁typically ▁repeated ▁every ▁six ▁months ▁for ▁the ▁first ▁two ▁years ▁after ▁diagn osis . ▁While ▁CT ▁of ▁the ▁l ungs ▁is ▁usually ▁ade qu ate , ▁a ▁posit ron ▁emission ▁tom ography ▁scan ▁of ▁the ▁body ▁may ▁also ▁be ▁performed ▁to ▁search ▁for ▁an ▁occ ult ▁tum our , ▁particularly ▁of ▁the ▁lung . ▁ ▁Tre at ment ▁ ▁If ▁LE MS ▁is ▁caused ▁by ▁an ▁underlying ▁cancer , ▁treatment ▁of ▁the ▁cancer ▁usually ▁leads ▁to ▁resolution ▁of ▁the ▁sympt oms . ▁Tre at ment ▁usually ▁consists ▁of ▁chem other apy , ▁with ▁radiation ▁ther apy ▁in ▁those ▁with ▁limited ▁disease . ▁ ▁Im m unos upp ression ▁Some ▁evidence ▁supports ▁the ▁use ▁of ▁int ra ven ous ▁imm un og lob ul in ▁( IV IG ). ▁Im m une ▁supp ression ▁tends ▁to ▁be ▁less ▁effective ▁than ▁in ▁other ▁auto imm une ▁dise ases . ▁Pred nis ol one ▁( a ▁gl uc oc ort ico id ▁or ▁ster oid ) ▁suppress es ▁the ▁imm une ▁response , ▁and ▁the ▁ster oid - s par