Vascular calcification and response to neoadjuvant therapy in locally advanced rectal cancer: an exploratory study.

PURPOSE: Patients with locally advanced rectal cancer (LARC) may experience a clinical complete response (cCR) to neoadjuvant chemoradiotherapy (NACRT) and opt for non-operative management. Pathological factors that relate to NACRT response have been well described. Host factors associated with response, however, are poorly defined. Calcification of the aortoiliac (AC) vessels supplying the rectum may influence treatment response. METHODS: Patients with LARC having NACRT prior to curative surgery at Glasgow Royal Infirmary (GRI) and St Mark's hospital (SMH) between 2008 and 2016 were identified. AC was scored on pre-treatment CT imaging. NACRT response was assessed using pathologic complete response (pCR) rates, tumour regression grades (TRGs), the NeoAdjuvant Rectal score and T-/N-downstaging. Associations were assessed using Chi-squared, Mantel-Haenszel and Fisher's exact tests. RESULTS: Of 231 patients from GRI, 79 (34%) underwent NACRT for LARC. Most were male (58%), aged over 65 (51%) with mid- to upper rectal tumours (56%) and clinical T3/4 (95%), node-positive (77%) disease. pCR occurred in 10 patients (13%). Trends were noted between higher clinical T stage and poor response by Royal College of Pathologist's TRG (p = 0.021) and tumour height > 5 cm and poor response by Mandard TRG (0.068). In the SMH cohort, 49 of 333 (15%) patients underwent NACRT; 8 (16%) developed a pCR. AC was not associated with NACRT response in either cohort. CONCLUSIONS: AC was not associated with NACRT response in this cohort. Larger contemporary cohorts are required to better assess host determinants of NACRT response and develop predictive models to improve patient selection.

Aortic calcification is associated with non-infective rather than infective postoperative complications following colorectal cancer resection: an observational cohort study.

OBJECTIVES: Complications following colorectal cancer resection are common. The degree of aortic calcification (AC) on CT has been proposed as a predictor of complications, particularly anastomotic leak. This study assessed the relationship between AC and complications in patients undergoing colorectal cancer resection. METHODS: Patients from 2008 to 2016 were retrospectively identified from a prospectively maintained database. Complications were classified using the Clavien-Dindo (CD) scale. Calcification was quantified on preoperative CT by visual assessment of the number of calcified quadrants in the proximal and distal aorta. Scores were grouped into categories: none, minor (< median AC score) and major (> median AC score). The relationship between clinicopathological characteristics and complications was assessed using logistic regression. RESULTS: Of 657 patients, 52% had proximal AC (> median score (1)) and 75% had distal AC (> median score (4)). AC was more common in older patients and smokers. Higher burden of AC was associated with non-infective complications (proximal AC 28% vs 16%, p = 0.004, distal AC 26% vs 14% p = 0.001) but not infective complications (proximal AC 28% vs 29%, p = 0.821, distal AC 29% vs 23%, p = 0.240) or anastomotic leak (proximal AC 6% vs 4%, p = 0.334, distal AC 7% vs 3%, p = 0.077). Independent predictors of complications included open surgery (OR 1.99, 95%CI 1.43-2.79, p = 0.001), rectal resection (OR 1.51, 95%CI 1.07-2.12, p = 0.018) and smoking (OR 2.56, 95%CI 1.42-4.64, p = 0.002). CONCLUSIONS: These data suggest that high levels of AC are associated with non-infective complications after colorectal cancer surgery and not anastomotic leak. KEY POINTS: • Aortic calcification measured by visual quantification of the number of calcified quadrants at two aortic levels on preoperative CT is associated with clinical outcome following colorectal cancer surgery. • An increased burden of aortic calcification was associated with non-infective complications but not anastomotic leak. • Assessment of the degree of aortic calcification may help identify patients at risk of cardiorespiratory complications, improve preoperative risk stratification and assign preoperative strategies to improve fitness for surgery.