Treatment of 5-fluorouracil refractory metastatic colorectal cancer: an Australian population-based analysis

Abstract

Randomised trials have established the importance of oxaliplatin (O) and irinotecan (I) in advanced colorectal cancer (CRC). However, patients enrolled in clinical studies represent a restricted population and little is known about the use of O and I in the general population and the subsequent outcomes outside clinical studies. We used the Australian Health Insurance Commission (HIC) database to describe prescribing patterns of O and I and their impact on survival in all patients with 5-fluorouracil (5-FU) refractory CRC in Australia in 2002 and 2003. In 2999 patients, there was a marked increase in initial treatment with O rather than I; 48% of patients received O first in 2002 vs 66% in 2003 ( P <0.001). Overall 40–45% of patients received both O and I; however, younger patients were more likely to receive both drugs ( P <0.001). After 5-FU failure and treatment with O or I, the proportion of patients surviving 6 or 12 months was estimated to be 0.67 (95% CI, 0.66–0.69) and 0.42 (95% CI, 0.40–0.44), respectively. Survival was superior for patients who received both O and I; however, the sequence of agents had no impact. Older patients (⩾70 years) had inferior survival no matter which drug was used as initial treatment. Analysis of the Australian HIC database provides a valuable means of assessing patterns of use and outcomes of new therapies.

Studies using Australia's Pharmaceutical Benefits Scheme data for pharmacoepidemiological research: a systematic review of the published literature (1987-2013)

“…30 However, the most recent PBS statistics highlight the growth, particularly in relation to PBS spend, on specialist-initiated medicines such as antineoplastics (cancer drugs). We have very limited research in this important and growing area of therapeutics [31][32][33][34] given cancer represents a significant disease burden in the Australian population. 30 Moreover, populations such as the elderly, children, pregnant women and those with multiple morbidities are studied rarely in pre-market evaluation.…”

Patterns of Colorectal Cancer Care in Europe, Australia, and New Zealand

“…These findings included changing trends over time and variation in rates of treatment by patient demographic and health characteristics (ie, age, gender, socioeconomic status, tumor stage, metastatic tumor status, presence of comorbidities), hospital setting and volume, and region (26,(28)(29)(30)34,(36)(37)(38)40,42,45,(46)(47)(48)55,60,61,66,68,69,72,78,79,88). Among these characteristics, patient age was one of the most consistent findings associated with treatment receipt, with older patients being less likely to receive colorectal cancer care compared with younger patients.…”

“…Several studies also indicated that younger patients were more likely to receive chemotherapy compared with older patients, though some highlighted rising rates of chemotherapy use among the elderly over time (28)(29)(30)40,46,47,60,61,66,68,69,78,79). Additionally, more advanced tumor stage greatly increased the likelihood of chemotherapy receipt (30,40,49,50,54,61,(63)(64)(65)(66)68,73,78,79).…”

Validation and application of a death proxy in adult cancer patients

“…These signs are especially useful in chronic disease populations where one would expect regular medical interactions, including the dispensing of prescribed medications. The death proxy approach has been demonstrated recently by Damianovich et al . who estimated 6‐ and 12‐month survival in Australian metastatic colorectal cancer patients prescribed oxaliplatin and irinotecan under the national Pharmaceutical Benefits Scheme (PBS).…”

“…These signs are especially useful in chronic disease populations where one would expect regular medical interactions, including the dispensing of prescribed medications. The death proxy approach has been demonstrated recently by Damianovich et al 3 who estimated 6-and 12-month survival in Australian metastatic colorectal cancer patients prescribed oxaliplatin and irinotecan under the national Pharmaceutical Benefits Scheme (PBS). At the time of the study, death data were not routinely collected by Medicare Australia, the PBS administering body, so the investigators classified patients as dead if they had no dispensing records for any drug after 6 and 12 months from entry into the study, respectively.…”