. 2015 Jun 3;36(11):8559–8571. doi: 10.1007/s13277-015-3616-7

Table 2.

Clinicopathological characteristics of inverted papilloma cases

	Variable	Cases n (%)
Symptoms	Nasal obstruction	64 (49.2)
	Rhinorhoea	71 (54.6)
	Feeling of pressure	24 (18.5)
	Impaired sense of smell	50 (38.5)
	Pain	20 (15.4)
	Epistaxis	9 (10.8)
	Diploplia	3 (2.3)
	None	8 (6.2)
Stage (Krouse classification)^a	pT1	40 (30.7)
	pT2	76 (58.5)
	pT3	13 (10.0)
	pT4 (squamous cell carcinoma)	1 (0.8)
Histological type^b	Endophytic growth	119 (91.5)
	Exophytic growth	11 (8.5)
	Cylindrical cell papilloma	0 (0.0)
Anatomical area occupied^c	Nasal cavity	97 (74.6)
	Maxillary sinuses	70 (53.8)
	Ethmoid anterior sinuses	43 (33.1)
	Ethmoid posterior sinuses	15 (11.5)
	Frontal sinuses	8 (6.1)
	Sphenoid sinuses	6 (4.6)
Anatomical sites occupied	1 region	61 (46.9)
Anatomical sites occupied	More regions	69 (53.1)
IP with dysplasia (mild or severe)	No	88 (67.7)
IP with dysplasia (mild or severe)	Yes	42 (32.3)
Ki67 IHC staining^d	Low	5 (3.8)
Ki67 IHC staining^d	High	46 (35.4)
Bone destruction	No	110 (84.6)
Bone destruction	Yes	20 (15.4)
Recurrences of IP	No	112 (86.2)
Recurrences of IP	Yes	18 (13.8)
IP associated with malignancy	No	129 (99.2)
IP associated with malignancy	Yes	1 (0.8)

^aKrouse staging system [28]

^bThe IARC WHO classification of head and neck tumors [29]

^cIn each IP case, one or more anatomical sites may be occupied simultaneously

^dLow (<14 % Ki67-positive cells); high (≥14 % Ki67-positive cells)