(ChemotherapyAdvisor) – Histological subtypes appear to explain ethnic disparities in uterine cancer survival, according to a retrospective, single-institution study published in Gynecologic Oncology.
African-American patients with uterine cancer “are much more likely to die and are much more likely to have non- endometrioid histologies than [are] white patients,” reported lead author David Smotkin, MD, Centennial Women’s Center, Bronx, New York.
The authors retrospectively analyzed medical and pathology records for all women diagnosed with uterine cancer at Montefiore Medical Center from 1999 through 2009 (n=984 women).
Overall uterine cancer incidence is known to be higher among Caucasian women, but mortality from this cancer is higher among African-American women, previous studies have shown. That pattern was observed in this study as well, with the hazard ratio (HR) for uterine cancer-associated death for African-American women compared to Caucasian patients being 1.94 (P<0.001) – but only when all histological subtypes were included in the analysis. The ethnic disparity in survival disappeared when histological differences were included in statistical analyses, the authors reported.
“There are no differences in survival among white, black or Hispanic women with uterine cancer, after control for histological subtype,” the authors wrote.
African-American women were significantly more likely than Caucasians to have non-endometrioid (papillary serous, carcinosarcoma, leiomyosarcoma) histologies (63% vs. 26%; P<0.001), they reported. Hispanic women had a “moderately higher proportion” of non-endometrioid uterine cancers than Caucasians (35% vs. 26%, P<0.02), the authors reported.
The distributions of cancer stage at diagnosis was similar, overall, for all ethnicities – but African-Americans were somewhat less likely to be diagnosed with stage-1 uterine cancer (41% of cases vs. 53% of cases diagnosed among Caucasian women; P=0.056).
“There was no survival disparity between blacks and whites for the endometrioid type, nor for non-endometrioid cancers,” the authors reported.
The reason more non-endometrioid cancers are seen among African-Americans remains unclear, they noted.