The Effect of Body Mass Index on the Creation of an End-Colostomy in Rectal Cancer Patients.

With the increasing prevalence of obesity, there has been a parallel increase in the incidence of rectal cancer. The association of body mass index (BMI) and end-colostomy creation versus primary anastomosis in patients undergoing proctectomy for rectal cancer has not been described. This is a retrospective study of patients with rectal cancer from 2012 to 2018 using data from the National Surgical Quality Improvement Project. 16,446 (92.1%) underwent primary anastomosis and 1,418 (7.9%) underwent creation of an end-colostomy. Patients with a BMI of 25-29.9 (overweight) comprised the most frequent group to have a proctectomy (reference group), but the least likely to have an end-colostomy. Patients with severe obesity (BMI 50+) had an adjusted odds ratio for end-colostomy of 2.7 (95% CI 1.5-4.7) compared to the reference group. Patients who have severe obesity should be counseled regarding the likelihood of an end-colostomy and may benefit from medical weight management or weight-loss surgery.

An analysis of sexual dimorphism in the tumor microenvironment of colorectal cancer.

Women with colorectal cancer (CRC) have survival advantages over men, yet the underlying mechanisms are unclear. T cell infiltration within the CRC tumor microenvironment (TME) correlates strongly with survival. We hypothesized that women with CRC have increased T cell infiltration and differential gene expression in the TME compared to men. Tissue microarrays comprising primary tumor, tumor infiltrated lymph nodes, and uninvolved colon were created from CRC patients. Proportions of CD4 positive (CD4+) and CD8 positive (CD8+) T cells were identified using immunohistochemistry. TME immune- and cancer-related genetic expression from primary and metastatic CRC tumor were also evaluated via the NanoStringIO360 panel and The Cancer Genome Atlas Project database. CD4+ was higher in tumor samples from women compared to men (22.04% vs. 10.26%, p=0.002) and also in lymph node samples (39.54% vs. 8.56%, p=0.001). CD8+ was increased in uninvolved colon from women compared to men (59.40% vs. 43.61%, p=0.015), and in stage I/II tumors compared to III/IV in all patients (37.01% vs. 23.91%, p=0.009). Top CD8+ tertile patients survived longer compared to the bottom (43.9 months vs. 25.3 months, p=0.007). Differential gene expression was observed in pathways related to Treg function, T cell activity, and T cell exhaustion, amongst several others, in women compared to men. Thus, significant sexual dimorphism exists in the TME that could contribute to survival advantages observed in female patients with CRC.

Defining incidence and outcome of contrast-induced nephropathy among trauma: is it overhyped?

Contrast-induced nephropathy (CIN) in trauma patients is uncommon and the incidence is unknown. We studied the incidence of CIN and its outcome. A retrospective chart review of trauma patients 16 years of age and older who were admitted to our Level I trauma center during 2005 was performed. Patients who received the intravenous contrast CT scan and had their serum creatinine (Cr) monitored at admission and at 48 to 72 hours were identified. CIN was defined as a 0.5-mg/dL rise of serum Cr or a 25 per cent increase from the baseline if the baseline Cr was abnormal. We excluded patients transferred from an outside facility, patients without repeated serum Cr measurements, patients who had cardiac arrest or persistent hypotension, and patients who had received N-acetylcysteine (Mucomyst) before their CT scan. We compared CIN and non-CIN groups. During 2005, 543 fit our study criteria, of whom 19 (3.5%) had CIN. CIN (vs non-CIN) had a higher baseline serum Cr (1.48 + 0.23 vs 1.06 + 0.02, P < 0.001), a longer intensive care unit stay (17 vs 5 days, P < 0.001), and a longer hospital stay (19 vs 8 days, P < 0.001); the mortality rate was not different (10 vs 4%, P = 0.2). We found elevated baseline serum Cr (OR, 1.92; 95% CI, 1.13 to 3.27; P = 0.016) to be associated with increased risk for CIN. All but two serum Cr levels peaked within 48 hours; all returned to baseline. One patient with an underlying congenital kidney disease required temporary dialysis. CIN incidence in trauma is low and the clinical course is benign.