Estimating the optimal chemotherapy utilisation rate as an evidence-based benchmark in cancers of the breast, upper gastrointestinal tract, gynaecological tract, head and neck, kidney, bladder, thyroid and unknown primary

Abstract

Background: There is a wide variation in the proportion of new cases of cancer who receive chemotherapy in Australia and internationally. We developed an evidence-based utilisation model to estimate the optimal proportion of new cases of cancer where chemotherapy is indicated at least once as a benchmark for measuring and improving the quality of care. Methods: The optimal utilisation rate was defined as the proportion of cancer patients for whom chemotherapy was the treatment of choice. We constructed an optimal chemotherapy utilisation model using indications for chemotherapy identified from evidence-based treatment guidelines. Population-based data on the proportion of patient and tumour-related attributes for which chemotherapy was indicated were obtained from Australian cancer registries where possible. Treatment indications and epidemiological data were merged using TreeAge Pro 2007 to calculate the optimal rate. Monte Carlo simulations and sensitivity analyses were used to assess the impact of controversial chemotherapy indications and variations in epidemiological data on our model. The optimal rate was compared with actual utilisation rates reported. Results: Chemotherapy was indicated at least once in 50.8% (95% CI 50.6-51%) of all new cancer patients. The optimal chemotherapy utilisation rates by tumour sites ranged from a low of 13% in thyroid cancers to a high of 94% in myeloma. The estimated optimal chemotherapy utilisation rates by tumour sites (except for liver cancer) were well above the actual rates reported (see Table 1 below). Table 1: Comparison of optimal and actual chemotherapy utilisation rates by tumour site Tumour Site Optimal Rate (%) Actual Rates (%) Breast 68 29-42 Colon 55 28-32 Lung 73 21-41 Rectum 64 42-54 Head and Neck 36 12-17 Unknown Primary 65 5-49 Pancreas 35 19-31 Stomach 83 10-34 Urinary Bladder 66 10-28 Kidney 33 3-7 Thyroid 13 1-2 Endometrium 20 2-12 Oesophagus 79 38-52 Gallbladder 80 22-24 Liver 27 22-37 Myeloma 94 76 Ovary 84 52-79 Conclusions: This evidence-based model generates an optimal chemotherapy utilisation rate which can serve as a valuable benchmark for comparison with patterns of care data. The actual chemotherapy utilisation rate appears to be substantially lower than the optimal rate in most tumour sites (except for liver cancer) suggesting that chemotherapy may be under-utilised in cancer treatment.