PD831 - HISTOMORPHOLOGICAL AND INFLAMMATORY DIFFERENCES BETWEEN SUBCUTANEOUS AND VISCERAL ADIPOSE TISSUE IN CANCER PATIENTS

PD831

HISTOMORPHOLOGICAL AND INFLAMMATORY DIFFERENCES BETWEEN SUBCUTANEOUS AND VISCERAL ADIPOSE TISSUE IN CANCER PATIENTS

G. Imbimbo^1,*, F. Tambaro¹, R. Carletti¹, S. Orlando¹, V. Rizzo², E. Belloni³, G. Nigri³, M. Muscaritoli¹, A. Molfino^1,4

¹Department of Translational and Precision Medicine, ²Department of Radiological, Oncological and Pathological Sciences, ³Department of Medical-Surgical Sciences and Translational Medicine, ⁴Department of Interdisciplinary Studies on WellBeing, Health and Environmental Sustainability (BeSSA), Sapienza University of Rome, Rome, Italy

Rationale: We previously examined histomorphological features and inflammatory infiltrates in subcutaneous adipose tissue (SAT) of patients with cancer cachexia (CC) and reduced adipocyte size, increased fibrosis, and enhanced inflammatory infiltration. The present study aimed to compare SAT and visceral adipose tissue (VAT) for histomorphology and inflammatory infiltration in cancer patients.

Methods: We enrolled gastrointestinal cancer patients undergoing surgery for cancer resection. Biopsies of SAT and VAT were collected from 15 patients (12 colon and 3 gastric cancer) for histomorphological analyses (cross-sectional area-CSA and fibrosis) and immunohistochemistry. CT scans at L3 were used to quantify SAT, VAT, and total adipose tissue (TAT) areas.

Results: CC was present in 8 patients. No significant differences emerged between CC and non-CC in histomorphological or immunohistochemical parameters. A trend toward higher T lymphocytes in SAT was observed in CC vs non-CC (p=0.072). In all patients, a higher number of macrophages and T lymphocytes were present in VAT vs SAT (p<0.05 and p<0.03). In non-CC, T-lymphocyte infiltration was higher in VAT vs SAT (p=0.018). TAT positively correlated with the SAT CSA (rho=0.671; p=0.006) and negatively with the number of CD3+ in VAT (rho=-0.557; p=0.031). VAT CSA negatively correlated with the number of macrophages in both VAT (rho=-0.670; p=0.006) and SAT (rho=-0.640; p=0.006).

Conclusion: Adipose tissue in gastrointestinal cancer shows depot-specific immune infiltration, with VAT enriched in macrophages and T lymphocytes compared to SAT, independent of CC.  Adiposity was associated with adipocyte morphology and immune cell distribution, suggesting a link between fat mass and local inflammatory dynamics.

Disclosure of Interest: None declared