Oesophageal cancer surgery : the role of co-morbidities

The overall aim of this thesis was to produce information which can be used to improve clinical decision-making in order to optimise treatment and improve the well-being of patients with oesophageal cancer following surgery. Oesophageal cancer is a devastating disease with poor prognosis. The most established curatively intended treatment involves major surgery, often in combination with neoadjuvant therapy, and comes with a high risk of morbidity and limited chance of long-term survival.

The clinical decision process of determining which patients would benefit from surgery is critically important. Several factors are considered when evaluating whether a patient is suitable for surgery or not, but the main factors are tumour stage, general fitness and comorbidity. The focus of this thesis focus was to assess how co-morbidities in general, and specific co-morbidities in particular, influence mortality, morbidity and health related quality of life (HRQOL) after surgery for oesophageal cancer. A subjective outcome such as HRQOL is of great importance in this patient group which adds an extra dimension to more objective outcomes in determining the outcome of the treatment.

The four studies included in the thesis were cohort studies from Sweden and England. Studies I and III were based on a prospective cohort including patients operated on between 2001 and 2005 in Sweden, and study II was based on a retrospective cohort of patients who underwent surgery between 1987 and 2010 in Sweden. Study IV used a prospective cohort of patients who underwent oesophagectomy at St Thomas’ Hospital London between 2011 and 2014/2015.

In studies I and II, co-morbidity was examined in relation to mortality after oesophageal cancer surgery. There was an increased risk of mortality among patients with a Charlson co-morbidity index score ≥2 and among patients with a history of myocardial infarction and congestive heart failure. Study III assessed co-morbidity in relation to morbidity after surgery. Patients with ≥1 co-morbidities or cardiac disease had an increased risk of severe post-operative complications. In study IV, co-morbidity was assessed in relation to HRQOL. Before surgery, patients with co-morbidities had worse HRQOL for several aspects, while at 6 months following surgery, patients had deteriorated in most HRQOL aspect regardless of co-morbidity status, except for the fact that patients with several comorbidities had worse physical function, fatigue and more trouble with coughing compared to those with fewer co-morbidities.

In conclusion, this thesis provides additional information on how co-morbidities affect outcomes following surgery for oesophageal cancer and could help to improve clinical decision-making for these patients.

List of scientific papers

I. Backemar L, Djärv T, Wikman A, Johar A, Ross P, Lagergren P, Lagergren J. The role of diabetes and other co-morbidities on survival after esophageal cancer surgery in a population-based study. American journal of surgery 2013;206(4): 539-543.
https://doi.org/10.1016/j.amjsurg.2013.01.035

II. Backemar L, Lagergren P, Johar A, Lagergren J. Impact of co-morbidity on mortality after oesophageal cancer surgery. The British journal of surgery 2015;102(9): 1097-1105
https://doi.org/10.1002/bjs.9854

III. Backemar L, Lagergren P, Djärv T, Johar A, Wikman A, Lagergren J. Comorbidities and Risk of Complications After Surgery for Esophageal Cancer: A Nationwide Cohort Study in Sweden. World journal of surgery 2015;39(9): 2282-2288.
https://doi.org/10.1007/s00268-015-3093-6

IV. Backemar L, Johar A, Wikman A, Zylstra J, Gossage J, Davies A, Lagergren J, Lagergren P. Co-morbidity and recovery of health related quality of life after oesophageal cancer surgery. [Manuscript]