B101: Use of continuous prophylactic dalteparin to reduce arterial and venous thromboembolism in patients undergoing neo-adjuvant and adjuvant cisplatin based chemotherapy for oesophago-gastric cancer

Martin Doak1,Lucy Wall1

1Edinburgh Cancer Centre, Scotland, UK

Presenting date: Tuesday 3 November
Presenting time: 12.20-13.10

Background

Cisplatin based chemotherapy confers a survival advantage in oesophago-gastric cancer patients undergoing surgery. Chemotherapy is associated with increased thrombotic risk.

In our previous study, 25% of these patients developed thrombosis with 40% requiring chemotherapy discontinuation and/or surgery cancellation.

Dalteparin administered only during inpatient chemotherapy did not reduce the rate of thrombosis.

We postulated that daily prophylactic dalteparin started with chemotherapy and continued until 6 weeks following surgery could reduce event rate and departmental protocol changed in January 2014.

Method

40 consecutive patients starting pre-operative chemotherapy in 2014 for oesophageal-gastric cancers were analysed for thrombotic events, thrombosis risk factors and impact on patient outcomes. Results were compared to 39 consecutive patients from 2012, who had received prophylactic dalteparin on inpatient chemotherapy days or no anti-coagulation.

Results

In the 2012 cohort, 10 (25.6%) experienced an event (10.3% venous and 15.4% arterial). Of the 2014 cohort, 5 (12.5%) experienced a thrombotic event (10% venous and 2.5% arterial); 2 patients had surgery delayed with 1 chemotherapy abandoned. Although the difference was not statistically significant (p=0.161), it is suggestive of reduced risk.

Both cohorts more commonly developed events pre-op than post-op (20.5% vs 5.1% and 7.5% vs 5%). 

There was no difference in median time from chemotherapy administration to event.

There was no difference in tumour-related factors between patients who developed thrombosis and those that did not. We found no association between Khoranna risk factors1, diabetes, hypertension or BMI and event rate.

A history of smoking was associated with events (Odds Ratio 2.4) but was not statistically significant.

No significant dalteparin complications were observed.

Conclusion

Use of prophylactic dalteparin appears to reduce the rate of thrombotic events by approximately 50%.

A lower pre-op event rate appears to increase the proportion completing chemotherapy and definitive surgery.

This could be confirmed with a randomised trial of different anti-coagulation strategies.