You won't find one-to-one matches for all your current codes. If a pathology report comes back with a hyperplasia diagnosis, then you have five possible ICD-9 codes to report. However, in ICD-10, you'll only have three options. Hyperplasia defined: An endometrial intraepithelial neoplasm is a precancerous lesion in the endometrium that makes the uterine lining more susceptible to endometroid endometrial adenocarcinoma. ICD-9-CM Codes 621.30, Endometrial hyperplasia, unspecified 621.31, Simple endometrial hyperplasia without atypia 621.32, Complex endometrial hyperplasia without atypia 621.33, Endometrial hyperplasia with atypia 621.35, Endometrial intraepithelial neoplasia [EIN] ICD-10-CM Codes N85.00, Endometrial hyperplasia, unspecified N85.01, Benign endometrial hyperplasia N85.02, Endometrial intraepithelial neoplasm [EIN] ICD-10 Change: Documentation: You'll find these codes in the Alphabetic Index as follows: Atypical, atypism -- - endometrium N85.9 -- hyperplasia N85.00 Endometritis (decidual) (nonspecific) (purulent) (senile) (atrophic) (suppurative) - hyperplastic (see also Hyperplasia, endometrial) N85.00 Hyperplasia, hyperplastic - endometrium, endometrial (adenomatous) (benign) (cystic) (glandular) (glandular-cystic) (polypoid) N85.00 -- with atypia N85.02 -- cervix -- see Dysplasia, cervix -- complex (without atypia) N85.01 -- simple (without atypia) N85.01 - glandularis cystica uteri (interstitialis) (see also Hyperplasia, endometrial) N85 - uterus, uterine N85.2 -- endometrium (glandular) (see also Hyperplasia, endometrial) N85.00 Hypertrophy, hypertrophic - endometrium (glandular) (see also Hyperplasia, endometrial) N85.00 Watch out: Coder Tips: You have an Excludes1 note underneath the N85.-- category, you'll see an Excludes1 note that forbids you from reporting these codes with endometriosis (N80.-), inflammatory diseases of uterus (N71-), noninflammatory disorders of cervix, except malposition (N86-N88), polyp of corpus uteri (N84.0), and uterine prolapse (N81-). You'll also find another Excludes1 note underneath N85.02 forbidding you from reporting this code with malignant neoplasm of endometrium (with endometrial intraepithelial neoplasia [EIN]) (C54.1).