title: Myxoid and Sarcomatoid Variants of Adrenocortical Carcinoma: Analysis of Rare Variants in Single Tertiary Care Center.
abstract: The aim of this study is to describe rare variants of adrenocortical carcinoma (ACC) and to compare the prognosis with that of conventional ACC. We retrospectively reviewed 8 cases of myxoid variant, 1 sarcomatoid variant, and 14 cases of conventional ACC, who underwent surgical resection at the Asan Medical Center between 1996 and 2014. An analysis of the clinicopathological characteristics, including the Weiss score, Ki-67 labeling index, and reticulin framework assessment is presented. The mean age of patients with myxoid/sarcomatoid ACC was 45 years; 4 out of 9 patients were women. Mean primary tumor size was 12.9 cm and the mean weight was 702.4 g. Seven patients presented in an advanced stage (stage III/IV); 8 of these eventually developed distant metastasis. The mean Weiss score was 5.0 points and the Ki-67 labeling index was 15.6%. The extent of myxoid or sarcomatoid change on histological examination ranged from 10% to 75% of the examined tumor areas; reticulin framework alteration was observed in all cases. Four patients showed venous tumor thrombus. Most of the clinicopathological parameters were not significantly different from those of conventional ACC. However, myxoid or sarcomatoid variant (hazard ratios [HR], 3.59; 95% confidence intervals [CI], 1.13-11.38; P = 0.030) and Ki-67 labeling index (HR, 3.97; 95% CI, 1.18-13.41; P = 0.030) were independent predictors of overall survival after adjusting for age and sex. Myxoid or sarcomatoid histological features or an increased Ki-67 labeling index may be associated with poor overall survival in patients with ACC.
authors.affiliation: Department of Surgery, University of Ulsan College of Medicine, Asan Medical Center, Seoul, Korea.
authors.forename: Tae Yon
authors.identifier: http://orcid.org/0000-0002-2179-6269
authors.initials: TY
authors.lastname: Sung
authors.affiliation: Department of Internal Medicine, Hallym University Dongtan Sacred Heart Hospital, Hwaseong, Korea.
authors.forename: Yun Mi
authors.identifier: http://orcid.org/0000-0001-8209-874X
authors.initials: YM
authors.lastname: Choi
authors.affiliation: Department of Internal Medicine, University of Ulsan College of Medicine, Asan Medical Center, Seoul, Korea.
authors.forename: Won Gu
authors.identifier: http://orcid.org/0000-0002-8404-7759
authors.initials: WG
authors.lastname: Kim
authors.affiliation: Department of Surgery, University of Ulsan College of Medicine, Asan Medical Center, Seoul, Korea.
authors.forename: Yu Mi
authors.identifier: http://orcid.org/0000-0002-8183-2604
authors.initials: YM
authors.lastname: Lee
authors.affiliation: Department of Internal Medicine, University of Ulsan College of Medicine, Asan Medical Center, Seoul, Korea.
authors.forename: Tae Yong
authors.identifier: http://orcid.org/0000-0003-4982-4441
authors.initials: TY
authors.lastname: Kim
authors.affiliation: Department of Internal Medicine, University of Ulsan College of Medicine, Asan Medical Center, Seoul, Korea.
authors.forename: Young Kee
authors.identifier: http://orcid.org/0000-0002-7911-9471
authors.initials: YK
authors.lastname: Shong
authors.affiliation: Department of Internal Medicine, University of Ulsan College of Medicine, Asan Medical Center, Seoul, Korea.
authors.forename: Won Bae
authors.identifier: http://orcid.org/0000-0003-4544-1750
authors.initials: WB
authors.lastname: Kim
authors.affiliation: Department of Pathology, University of Ulsan College of Medicine, Asan Medical Center, Seoul, Korea. hipuha@hanmail.net.
authors.forename: Dong Eun
authors.identifier: http://orcid.org/0000-0002-9583-9794
authors.initials: DE
authors.lastname: Song
mesh_terms: D000306:Adrenal Cortex Neoplasms / Q000175:diagnosis* / Q000401:mortality / Q000473:pathology; D018268:Adrenocortical Carcinoma / Q000175:diagnosis* / Q000401:mortality / Q000473:pathology; D000328:Adult; D005260:Female; D006801:Humans; D007150:Immunohistochemistry; D019394:Ki-67 Antigen / Q000378:metabolism; D008297:Male; D008875:Middle Aged; D009362:Neoplasm Metastasis; D009367:Neoplasm Staging; D011379:Prognosis; D016016:Proportional Hazards Models; D012189:Retrospective Studies; D012509:Sarcoma / Q000175:diagnosis* / Q000401:mortality / Q000473:pathology; D015996:Survival Rate; D062606:Tertiary Care Centers; D055815:Young Adult
chemical_list: D019394:Ki-67 Antigen
keywords: Adrenocortical Carcinoma; Ki-67; Myxoid; Sarcomatoid; Survival