Neurothekeoma located in the hallux and axilla: Two case reports

Table 1 Main points in the differential diagnosis between neurothekeomas and several other diseases

	NTK	DNSM	PFH	EFH	Spitz nevus
Average age	Adult/teenager	Adult	Teenager	Adult/teenager	Teenager/adult under 35
Sex	Female	Both	Female	Female	Female
Predilection site	Head/upper limbs/trunk	Finger/lower limbs	Upper limbs/trunk	Lower limbs	Face/head/lower limbs
Tumour boundary	Blurred	Clear	Clear	Clear	Clear
Arrangement of tumour cells	Lobular/nodular/clump/whirlpool like	Lobular/nodular	Nodular/clump	Mosaic or whirlpool-like	Nested
Tumour cell morphology	Round/oval/spindle	Round/oval/spindle	Round/oval/spindle	Round/oval	Polygon/spindle
Atypia of tumour cells	Mild-moderate	Rare	Rare	Rare	Rare
Mitosis of nucleus	0-25/WHPF	-	Rare	Rare	Rare
Immunohistochemical phenotype	CD10(+); CD63(+); mitf(+)	S-100(+); GFAP(+); SOX10(+)	S-100(+); vimentin(+); lysozyme(+)	ALK(+); TFE3(+); S-100(-)	S-100(+); HMB-45(+)

WHPF: Wide high-power field eyepiece 22 mm, sp 40x objective; NTK: Neurothekeoma; DNSM: Dermal nerve sheath myxoma; PFH: Plexiform fibrous histiocytoma; EFH: Epithelioid fibrous histiocytoma; GFAP: Glial fibrillary acidic protein.