PURPOSE: To evaluate the growth pattern depicted by MR imaging and used to differentiate between uterine cervcal and endometrial carcinoma where the mass involves both the uterine corpus and cervix. MATERIALS AND METHODS: The tumor growth pattern observed on MR images obtained between November 1989 and January in 1999 in 37 of 784 cervical carcinomas and 9 of 47 endometrial carcinomas in which the tumor involved both the uterine corpus and cervix was analysed. The histologic type was squamous (n=29), adenocarcinomatous (n=6) or adenosquamous (n=2) in cervical carcinoma, and carcinomatous (n=8) or adenosquamous (n=1) in endometrial carcinoma. A 1.5-T (Magnetom Vision, Siemens, Germany) and a 2.0-T unit (Spectro-20000, Goldstar, Korea) were used to obtain T1-and T2-weighted axial, T2-weighted sagittal and Gdenhanced images. Tumor involvement of the uterine cervix was classified as either partial(Cp) or total(Ct), and partial involvement(Cp) was subclassified as Cp-n, Cp-x, or Cp-b according to involvement of the endocervix, exocervix or both. Tumors of the uterine corpus were classified as involving the mucosa(U-mu), myometrium(U-my) or serosa(U-se). RESULTS: In 37 cases of cervical carcinoma, all three involving the endocervix(Cp-n) invaded the endometrium(U-mu), three involving both the endo- and exocervix(Cp-b) invaded the endometrium(U-mu, 1 case), myometrium(U-my, 1 case), or serosa(U-se, 1 case), and 31 involving the full-thickness of the uterine cervix(Ct) invaded the endometrium (U-mu, 6 cases) or serosa(U-se, 25 cases). In nine cases of endometrial carcinoma, three involving the endometrium(U-mu) and five involving the myometrium(U-my) invaded the endocervix(Cp-n), and one involving the serosa(U-se) invaded the full-thickness of the uterine cervix(Ct). CONCLUSION: Cervical carcinoma tended to involve the entire cervix and the full thickness of the uterine corpus, but endometrial carcinoma tended to involve the endometrium or myometrium of the uterine corpus and endocervix.