Clinician Ordering and Management Patterns of Urine Toxicology Results at a Cancer Center

Context: Opioid therapy is a cornerstone for treatment of cancer-related pain, but standardized management practices for patients with cancer and aberrant urine drug test (UDT) results are lacking.

Objectives: To identify the prevalence of UDT ordering (both screening and definitive testing) in the oncology setting and to examine clinician management practices for patients with cancer on opioid therapy with aberrant definitive UDT results.

Methods: We conducted a retrospective chart review of patients with cancer on opioid therapy at an academic cancer center in the United States. Outcomes included UDT ordering patterns and clinician management practices in response to aberrant definitive UDT results.

Results: Our study revealed an overall UDT ordering rate of 3.7% among 10,371 patients with cancer on opioid therapy. Among 143 patients for whom definitive UDTs were ordered, oncologists only ordered 14 (9.8%) UDTs, while palliative care ordered the majority (n = 129; 90.2%). Fifty-five (38.5%) patients had aberrant results, and the most common aberrancy was presence of illicit drugs 22 [15.4%]. Clinicians rarely made medication changes (20 [36.4%]) when UDT results were aberrant, and in the setting of possible fentanyl use (n = 8), only 3 (37.5%) patients were started/switched to methadone, and none were started/switched to buprenorphine.

Conclusion: Overall UDT ordering was infrequent for patients with cancer on opioid therapy, especially by oncologists, and clinicians rarely made prescribing changes when definitive UDT results were aberrant. More definitive guidance related to UDT ordering and opioid management are needed for patients with cancer and aberrant UDT results.