Clinical pharmacogenomic testing impacts therapy decisions and supportive medication choices in breast cancer

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Background: Pharmacogenomics, the study of the interaction between the patient’s genome and therapeutic drug response, evaluates the associations between efficacy and toxicity through analysis of drug metabolizing enzymes. As personalized medicine advances to the forefront of cancer care, pharmacogenomics can evaluate the individual’s ability to metabolize key medications in breast cancer treatment including anti-emetics, opioids, and tamoxifen. Women who do not achieve optimal levels of the active metabolites of tamoxifen are at higher risk of recurrence. Patients on chemotherapy who do not respond to anti-emetics can suffer from nausea and vomiting resulting in dehydration and hospitalization. This project evaluates the feasibility and therapeutic impact of real time pharmacogenomics in a selection of patients at the Inova Schar Cancer Institute (ISCI). Methods: An interdisciplinary team was created through the ISCI and the Inova Translational Medicine Institute to implement cheek swab based pharmacogenomic testing in 50 new patients undergoing mastectomy or neoadjuvant chemotherapy for breast cancer. Study patients were assessed for genotypic variability of key CYP enzymes and resulting impact on anti-emetic choices, perioperative pain control, and tamoxifen use. Results: Data was collected in a RedCap database. The 50 women enrolled were ages 28-83. Cheek swabs were performed in clinic and median turn around time was 7 days. 24 distinct genotypes were found in the 50 patients. 20% had abnormal CYP2D6 phenotypes indicating abnormalities in tamoxifen metabolism. 28% of patients had results leading to changes in dose or medication choice of perioperative pain control. 6% of patients had a CYP2D6 ultra-rapid metabolizer phenotype and were given granisetron in lieu of ondansetron. These patients had no documented nausea or vomiting requiring dose adjustments to the treatment plan or medical intervention. 40% of patients had results recommending avoidance of tamoxifen, 75% of which have ER+ breast cancer. 25% of patients had recommended changes to the dose of tamoxifen. Conclusions: Pharmacogenomic testing is feasible and available real-time for immediate use in the clinic. CYP mutations impact treatment decisions in a significant proportion of patients. Individualized treatment plans tailored to pharmacogenomic recommendations can be created in the multi-disciplinary setting and may decrease side effects of treatment and improve efficacy of curative therapy.

Strategies for integrating personalized medicine into healthcare practice

Aim: Research and innovation in personalized medicine are surging, however, its adoption into clinical practice is comparatively slow. We identify common challenges to the clinical adoption of personalized medicine and provide strategies for addressing these challenges. Methods: Our team developed a list of common challenges through a series of group discussions, surveys and interviews, and convened a national summit to discuss solutions for overcoming these challenges. We used a framework approach for thematic analysis. Results: We categorized challenges into five areas of need: education and awareness; patient empowerment; value recognition; infrastructure and information management; and ensuring access to care. We then developed strategies to address these challenges. Conclusion: In order for healthcare to transition into personalized medicine, it is necessary for stakeholders to build momentum by implementing a progression of strategies.

Chronic renal dysfunction following liver transplantation

With most of the immunosuppressive protocols consisting of calcineurin inhibitors (CI), nephrotoxicity has become a major long-term complication often compromising outcome. In a single-center retrospective study, we reviewed 1173 liver transplantations to identify variables indicative for the occurrence of chronic renal dysfunction (CRD) (defined as > or = 1 episode of serum creatinine increase > or = 1.8 mg/dL > or = 2 wk). Chronic renal dysfunction was found in 137 (11.7%) of all transplants [82 (7%) early (after 3-12 months), 55 (4.7%) late-onset (> 12 months)]. Compared to 5-/10-yr survival rates in non-CRD transplants (84/74%) survival was significantly decreased in early (66/46%), but unchanged in late-onset CRD (98/86%). Rates of alcoholic cirrhosis and prior renal dysfunction were significantly increased in patients with CRD. In a multivariate logistic regression analysis, only cyclosporine A (CyA) as immunosuppression remained an independent risk factor. No correlations to age, gender, rejection/retransplantation or diabetes were found. Surprisingly, renal function (creatinine) showed no difference between patients on CI monotherapy (FK/CyA) compared to those who had mycophenolate mofetil (MMF) added. In liver transplantation, early onset CRD significantly compromises survival. CyA-based immunosuppression appears to have a stronger impact than FK. The fact that patients with long-term severe chronic renal dysfunction failed to improve under MMF rescue therapy emphasizes the importance of new diagnostic strategies to earlier identify at-risk patients.