▁mouth . ▁ ▁On ▁ne uro log ical ▁exam ination , ▁the ▁weak ness ▁demonstrated ▁with ▁normal ▁testing ▁of ▁power ▁is ▁often ▁less ▁severe ▁than ▁would ▁be ▁expected ▁on ▁the ▁basis ▁of ▁the ▁sympt oms . ▁Str ength ▁impro ves ▁further ▁with ▁repeated ▁testing , ▁e . g . ▁improvement ▁of ▁power ▁on ▁repeated ▁hand ▁g rip ▁( a ▁phenomen on ▁known ▁as ▁" L am bert ' s ▁sign "). ▁At ▁rest , ▁ref lex es ▁are ▁typically ▁reduced ; ▁with ▁mus cle ▁use , ▁ref lex ▁strength ▁increases . ▁This ▁is ▁a ▁characteristic ▁feature ▁of ▁LE MS . ▁The ▁pup ill ary ▁light ▁ref lex ▁may ▁be ▁sl ugg ish . ▁ ▁In ▁LE MS ▁associated ▁with ▁lung ▁cancer , ▁most ▁have ▁no ▁suggest ive ▁sympt oms ▁of ▁cancer ▁at ▁the ▁time , ▁such ▁as ▁c ough , ▁c ough ing ▁blood , ▁and ▁un intent ional ▁weight ▁loss . ▁ ▁LE MS ▁associated ▁with ▁lung ▁cancer ▁may ▁be ▁more ▁severe . ▁ ▁C aus es ▁LE MS ▁is ▁often ▁associated ▁with ▁lung ▁cancer ▁( 5 0 – 7 0 % ), ▁specifically ▁small - cell ▁car cin oma , ▁making ▁LE MS ▁a ▁par ane op last ic ▁synd rome . ▁Of ▁the ▁people ▁with ▁small - cell ▁lung ▁cancer , ▁ 1 – 3 % ▁have ▁LE MS . ▁In ▁most ▁of ▁these ▁cases , ▁LE MS ▁is ▁the ▁first ▁sympt om ▁of ▁the ▁lung ▁cancer , ▁and ▁it ▁is ▁otherwise ▁asympt om atic . ▁ ▁LE MS ▁may