ASPO Abstracts
Visceral fat varies by sex despite similar BMIs among renal cell carcinoma patients
Category: Cancer Health Disparities
Conference Year: 2022
Abstract Body:
INTRODUCTIONMen have a higher renal cell carcinoma (RCC) incidence compared to women. Obesity, particularly abdominal obesity, is a risk factor for RCC and men tend to deposit fat abdominally to a greater extent compared to women. This study aims to examine the compositional differences in abdominal visceral adipose tissue (VAT), subcutaneous adipose tissue (SAT) and abdominal muscle (AM) by sex for RCC patients.METHODSIn this study, pre-operative MRI or CT scans from 32 patients with clear cell RCC were used to evaluate VAT, SAT and AM. Using SliceOmatic software (Tomovision, Canada) a axial, abdominal slice at the L3/L4 intervertebral space was segmented for all patients. For each of the MRI and CT image scans, minimum and maximum thresholds were set starting at -150 to -50 HU for VAT, -190 to -30 HU for SAT and -29 to 150 HU for AM. Thresholds were adjusted as necessary to accurately capture all region of interest. SPSS (v28, Chicago, IL) was used to run T-tests to compare the values from men and women for each variable, and for inter-class correlations to assess precision of the image analyses.RESULTSThe sample was comprised of 19 men (aged 40-75yr, mean: 61yr) and 13 women (aged 21-78yr, mean: 50yr) of either Non-Hispanic White (n=13) or Hispanic ethnicity (n=19). Mean Body Mass Index (BMI) values were 32.4±7.2 kg/m2 in men and 32. 9±13.2 kg/m2 in women (p = 0.907). 8 men (42.1%) were diagnosed with Stage III RCC, compared to 5 women (38.5%) being diagnosed with either Stage III or IV RCC. Mean VAT area was 272±120.0 cm2 for men and 179.7±92.3 cm2 for women (p = 0.026). SAT mean area was 278±170 cm2 for men, and 339±201.6 cm2 for women (p = 0.36). Mean AM area was 169.3±41.6 cm2 for men and 118.2±26.5 cm2 for women (p <.001). Interclass correlation coefficients were 0.997 for VAT, 0.994 for SAT and 0.991 for AM.CONCLUSIONDespite similar BMIs, women had significantly less VAT and a lower prevalence of RCC than men in this study. Prospective studies are needed to determine whether the higher VAT observed in men is a driver of the increased prevalence of RCC in men compared to women.
Keywords: renal cell carcinoma, visceral adipose tissue, body composition, MRI, sex