Emergency presentation of colon cancer

Abstract: Colon cancer is the second most common form of non-skin cancer in Sweden for men and women respectively. Up to one fourth of all colon cancer cases are reported to present as emergencies, which is associated with a higher postoperative mortality and a lower 5 year survival, and affects the total survival in the colon cancer group. The overall aim of this thesis was to explore factors associated with emergency presentation of colon cancer. In a population-based record study (n=604) including all patients from the GDH in Eskilstuna, 1996- 2005 it was found that the rate of emergency cases using a strict definition was 17% . These patients had more late-stage cancers and were most frequent during summer (36%), (the corresponding number for elective cases was 16%, 7.8; p<0.049) (I). An even larger population-based record study (n=853) was also performed including four different counties in the Uppsala-Örebro region, 2006-2008. The symptom profile differed according to mode of presentation and 54% in the subacute (reported as emergencies, but operated after >3 days from admittance) group had reported ≥2 symptoms associated to colon cancer the last 12 months prior to surgery, and 44% had already undergone a recent examination of the large bowel. Postoperative and 90-days mortality were lower in the acute group (8% and 15%) but more pronounced in the subacute group (15% and 28%). Five-year survival was 40% in the acute group and the corresponding number in the subacute group was 28% (II). The association between socioeconomic factors (SES) and mode of presentation was investigated in a register study including all patients with colon cancer in the Stockholm and Uppsala-Örebro regions 1997-2006 (n=12 293). Emergency presentation of colon cancer was most common in patients above the age of 80 (27.8%), stage IV (34.6%) and among patients with the lowest income (Q1) (27.7%). In a multiple regression model, OR for emergency presentation was 1.24 (95% CI 1.04-1.49) for unmarried and 1.22 (95% CI 1.03-1.45) for low income patients (III). Within the context of this thesis a pilot study concerning gene expression was also performed in which differences between emergency and elective colon cancer was found.