Risk Factors of Recurrence and Malignant Transformation of Sinonasal Inverted Papilloma

Table 2

Factors elevating the risk of recurrence of inverted papilloma, as quoted by the literature available.

Factor described	Publications
Young age of patients	Jardine et al., 2000 [12]
Female sex	Suh et al., 1977 [13]
Tobacco smoking	Roh et al., 2016 [14]; Jardine et al., 2000 [12]
Histopathological
(i) Enhanced hyperkeratosis	Katori et al., 2006 [15]
and presence of squamous hyperplasia
(ii) Elevated mitotic index
(iii) Lack of inflamed polyps
(iv) Greater amount of aneuploid cells	Liu, 1990 [16]