The effect of socioeconomic deprivation on presentation stage and long-term outcomes in patients undergoing colorectal cancer resection in Western Sydney.

BACKGROUND: While socioeconomic deprivation has been shown to affect survival in colorectal cancer, other factors such as global region of birth and ethnicity also exert an effect. We wished to ascertain the influence of socioeconomic deprivation on stage of presentation and cancer survival in an ethnically diverse Australian population. METHODS: Cases from a database of resections in Western Sydney (n = 1596) were stratified into cohorts of socioeconomic quintiles. Univariate analysis was used to compare demographics, AJCC stage and histopathological details between the least and most socioeconomically deprived groups. Kaplan-Meier analysis and log-rank testing were used to compare cancer-specific and all-cause 5-year survival between the most deprived quintile and all others, after case-control matching for age and overseas birth. RESULTS: A total of 322 (20.2%) patients from the most socioeconomically deprived centile, and 275 (17.2%) from the least were compared. The most deprived were significantly more likely to be aged under 70 (54.1% vs. 44.4%, p = 0.019), born overseas (54.3% vs. 38.6%, p = 0.003), present with stage III disease (37.4% vs. 26.7%, p = 0.005), perforated (12.5% vs. 5.3%, p = 0.005) or circumferential tumours (37% vs. 24.3%, p = 0.043). There was no significant difference in proportions presenting with metastatic disease, or 5-year survival between the most deprived quintile and all others after correction for age and foreign birth. CONCLUSIONS: Socioeconomic deprivation is associated with unfavourable colorectal cancer presentation stage but not poorer 5-year survival in our Western Sydney population. The reasons for this are unclear and demand further attention.

Clinicopathological factors associated with positive circumferential margins in rectal cancers.

BACKGROUND: Positive circumferential resections are associated with local disease recurrence and reduced survival in rectal cancer. We studied a cohort of consecutive rectal cancer resections to assess for clinicopathological differences and survival in patients with positive and negative circumferential margins. METHODS: Rectal cancers were identified from a retrospective histopathology database of colorectal resections performed at five western Sydney hospitals from 2010 to 2016. Univariate and multivariate analysis with binary logistic regression were performed on histopathology data matched with survival times from the New South Wales Registry of Births Deaths and Marriages. RESULTS: A total of 502 rectal cancer patients were identified including 66 (13.1%) with involved circumferential margins. Patients with positive and negative circumferential margins had a similar distribution of age, gender and use of neoadjuvant radiotherapy. Tumours with involved circumferential margin comprised 98.5% T3 and T4 disease of which 51.5% received neoadjuvant radiotherapy. These were significantly associated with metastatic disease, increasing tumour size, circumferential and perforated tumours on univariate analysis. Multivariate analysis identified abdomino-perineal resection (odds ratio (OR) 3.35; P = 0.003), en-bloc multivisceral resection (OR 2.56; P = 0.032), T4 stage (OR 6.99; P < 0.001), perineural (OR 5.61; P < 0.001) and vascular invasion (OR 2.46; P = 0.022) as independent risk factors. Five-year survival was significantly worse for patients with involved circumferential margins (26% versus 69%; P < 0.001). CONCLUSION: Circumferential margin status reflects not only technical success but also aggressive disease phenotypes which require adjuvant therapy. Further work is needed to determine whether omission of radiotherapy has had an effect on long-term outcomes in some of our at-risk patients.