Muscular involvement of extranodal natural killer/T cell lymphoma misdiagnosed as polymyositis: A case report and review of literature

Table 1 Comparisons with previous cases of extranodal natural killer/T cell lymphoma with manifested myopathic symptoms

Ref.	Age/sex	Initial diagnosis	Muscle involvement	Other involved organs	EBV	Outcome	Survival from initial onset
Kawaguchi et al[8]	54/M	GM	Generalized muscle, face, jaw, pharynx	Skin, liver, spleen	+	Death	19 mo
Yap et al[9]	73/M	PE	Left pectoralis major	-	+	Recovery	-
Yang et al[10]	23/M	PhM	Left lower limb	Nasopharynx, spleen	+	Death	2 mo
Min et al[11]	53/M	GM	Right lower extremity	Nasal, skin	+	Death	8 mo
Chan et al[12]	68/F	PM	Right forearm, face	Lung, oropharynx	+	Death	1.5 mo
Chim et al[4]	34/F	PM	Right forearm	Liver, bone marrow	+	Death	Unknown
Paik et al[13]	52/F	PE	Both lower limbs	Lung	+	Death	26 mo
Our case	42/M	PM	Both lower limbs, face	Pharynx, eyelid, optic nerve	+	Improved	-

GM: Granulomatous myositis; PE: Peripheral eosinophilia; PhM: Phlegmonous myositis; PM: Polymyositis; M: Male; F: Female; +: Positive; -: Negetive; EBV: Epstein-Barr virus.