Pre-90Y hepatic radiotherapy hemoglobin and liver functions to predict overall survival in unresectable, chemotherapy-refractory metastatic colorectal cancer.

Abstract

292 Background: Patients with liver metastases from colorectal cancers (mCRC) can benefit from 90Y resin microsphere radioembolization (RE) administered via the hepatic arteries. This study investigated which standard laboratory tests may assist in improving treatment outcomes by identifying potentially correctable pre-radiation abnormalities prior to delivery of RE. Methods: A database containing retrospective review of 606 mCRC patients treated consecutively from July 2002 to December 2011 at 11 US institutions was used. Data collected included background characteristics, prior chemotherapy, surgery/ablation, radiotherapy, vascular procedures, 90Y treatment, subsequent adverse events and survival. Kaplan-Meier estimates compared survival of patients across lines (0–≥4) of chemotherapy. The following values were obtained within 10 days prior to treatment: hemoglobin, albumin, alkaline phosphatase, AST, ALT, total bilirubin and creatinine. CTCAE v3.0 grade was assigned to each parameter and analyzed for impact on survival by line of chemotherapy. Where applicable, Consensus Guidelines were used to establish the abnormal limits for RE. Results: 606 patients (370 Male; 236 Female) were studied with a median follow-up of 8.5 months (IQR 4.3–15.6) after RE. Fewer than 11% of patients were treated outside recommended guidelines, with grade 2 albumin (<3–2.0 g/dL) being the most common (10.5%) at time of RE. Abnormal parameters (grade >0) were associated with statistically significantly decreased median survivals (p<0.05) and this was consistent across most lines of prior chemotherapy. Compared to patients with grade 0, those with grade 2 albumin decreased median survival by 67%; for grade 2 total bilirubin, by 63%; and grade 1 hemoglobin, by 66%. Conclusions: Review of pre-RE laboratory parameters may aid in improving median survivals if correctable grade >0 values are addressed prior to radiation delivery. Hemoglobin <10 g/dL is a well-known negative factor in radiation response and is easily corrected. Improving other parameters is more challenging. These efforts are important in optimizing treatment response to liver radiotherapy.