Table 1. Review of immunohistochemistry studies of malignant proliferating trichilemmal tumors.

Abbreviations: >, greater than; CD, cluster of differentiation; CK, cytokeratin; CR, current report; F, female; IHC, immunohistochemistry; M, male; NS, not stated; PHH3: phosphohistone H3; UEA-I: Ulex europaeus agglutinin-I

^aImmunohistochemistry on the initial tumor showed 25% positivity for Ki-67. At three-year and four-year follow-up, the tumor showed 40% and 60% positivity for Ki-67, respectively.

Case	Patient Characteristics (Age, Sex)	Results of IHC	Reference
1	NS, NS	Positive for p53	Urano et al., 1992 [8]
2	57, M	Weakly positive for UEA-I	Ko et al., 1996 [9]
3	95, M	Weakly positive for UEA-I	Ko et al., 1996 [9]
4	56, F	Negative for UEA-I	Ko et al., 1996 [9]
5	32, M	Increasing Ki-67 positivity as the extent of the tumor advanceda	Park et al., 1997 [10]
6	64, F	Negative for CD34	Herrero et al., 1998 [11]
7	53, M	Negative for CD34	Herrero et al., 1998 [11]
8	66, F	Negative for CD34	Herrero et al., 1998 [11]
9	32, M	Positive for chromogranin A; positive for p53	Nakai et al., 2008 [12]
10	58, F	<1% CD34 reactivity; positive for Ki-67; strong diffuse nuclear positivity for p53	Chaichamnan et al., 2010 [13]
11	41, F	20% CD34 reactivity; positive for Ki-67; strong diffuse nuclear positivity for p53	Chaichamnan et al., 2010 [13]
12	65, F	CD34 positivity in >70% of tumor cells; Ki-67 positivity in 20% of tumor cells; strong diffuse nuclear positivity for p53; positive for calretinin	Gulati et al., 2011 [14]
13	52, F	40% CD34 reactivity; 20% Ki-67 reactivity; 80% p53 reactivity	Alici et al., 2015 [15]
14	67, M	Positive for Ki-67; positive for PHH3	Fieleke et al., 2015 [2]
15	42, M	Positive for CD34	Liu et al., 2016 [16]
16	46, F	Negative for CD34; negative for CK7; strongly positive for CK17; strong diffuse nuclear positivity for p53	CR