PGR and endometrial cancer: However, recent studies indicated that; (1) type 1 and type 2 endometrial cancer share a common pathogenesis and common risk factors [4], for example, a high body mass index (BMI) [5,6], (2) there was no difference in the gonadal hormonal levels between women with type 1 and type 2 endometrial cancer [7], (3) there is no difference in the positivity of oestrogen or progesterone receptor between type 1 and type 2 endometrial cancer [8], and (4) the protective factor in the incidence of endometrial cancer by parity applies to both type 1 and 2 endometrial cancer to a similar degree [9].