Chemotherapy Dose Density in Early-Stage Breast Cancer and Non-Hodgkin’s Lymphoma

Pharmacogenetics of toxicity of 5-fluorouracil, doxorubicin and cyclophosphamide chemotherapy in breast cancer patients

The differences in patients' response to the same medication, toxicity included, are one of the major problems in breast cancer treatment. Chemotherapy toxicity makes a significant clinical problem due to decreased quality of life, prolongation of treatment and reinforcement of negative emotions associated with therapy. In this study we evaluated the genetic and clinical risk factors of FAC chemotherapy-related toxicities in the group of 324 breast cancer patients. Selected genes and their polymorphisms were involved in FAC drugs transport (ABCB1, ABCC2, ABCG2,SLC22A16), metabolism (ALDH3A1, CBR1, CYP1B1, CYP2C19, DPYD, GSTM1, GSTP1, GSTT1, MTHFR,TYMS), DNA damage recognition, repair and cell cycle control (ATM, ERCC1, ERCC2, TP53, XRCC1). The multifactorial risk models that combine genetic risk modifiers and clinical characteristics were constructed for 12 toxic symptoms. The majority of toxicities was dependent on the modifications in components of more than one pathway of FAC drugs, while the impact level of clinical factors was comparable to the genetic ones. For the carriers of multiple high risk factors the chance of developing given symptom was significantly elevated which proved the factor-dosage effect. We found the strongest associations between concurrent presence of clinical factors - overall and recurrent anemia, nephrotoxicity and early nausea and genetic polymorphisms in genes responsible for DNA repair, drugs metabolism and transport pathways. These results indicate the possibility of selection of the patients with expected high tolerance to FAC treatment and consequently with high chance of chemotherapy completion without the dose reduction, treatment delays and decline in the quality of life.

Effect of virtual reality on time perception in patients receiving chemotherapy

PURPOSE

Virtual reality (VR) during chemotherapy has resulted in an elapsed time compression effect, validating the attention diversion capabilities of VR. Using the framework of the pacemaker-accumulator cognitive model of time perception, this study explored the influence of age, gender, state anxiety, fatigue, and cancer diagnosis in predicting the difference between actual time elapsed during receipt of intravenous chemotherapy while immersed in a VR environment versus patient's retrospective estimates of time elapsed during this treatment.

MATERIALS AND METHODS

This secondary analysis from three studies yielded a pooled sample of N = 137 participants with breast, lung, or colon cancer. Each study employed a crossover design requiring two matched intravenous chemotherapy treatments, with participants randomly assigned to receive VR during one treatment. Regressions modeled the effect of demographic variables, diagnosis, and Piper Fatigue Scale and State Anxiety Inventory scores on the difference between actual and estimated time elapsed during chemotherapy with VR.

RESULTS

In a forward regression model, three predictors (diagnosis, gender, and anxiety) explained a significant portion of the variability for altered time perception (F=5.06, p = 0.0008). Diagnosis was the strongest predictor; individuals with breast and colon cancer perceived time passed more quickly.

CONCLUSIONS

VR is a noninvasive intervention that can make chemotherapy treatments more tolerable. Women with breast cancer are more likely and lung cancer patients less likely to experience altered time perception during VR (a possible indicator of effectiveness for this distraction intervention). Understanding factors that predict responses to interventions can help clinicians tailor coping strategies to meet each patient's needs.

No Evidence of Clonal Dominance in Primates up to 4 Years Following Transplantation of Multidrug Resistance 1 Retrovirally Transduced Long-Term Repopulating Cells

Previous murine studies have suggested that retroviral multidrug resistance 1 (MDR1) gene transfer may be associated with a myeloproliferative disorder. Analyses at a clonal level and prolonged long-term follow-up in a model with more direct relevance to human biology were lacking. In this study, we analyzed the contribution of individual CD34-selected peripheral blood progenitor cells to long-term rhesus macaque hematopoiesis after transduction with a retroviral vector either expressing the multidrug resistance 1 gene (HaMDR1 vector) or expressing the neomycin resistance (NeoR) gene (G1Na vector). We found a total of 122 contributing clones from 8 weeks up to 4 years after transplantation. One hundred two clones contained the G1Na vector, whereas only 20 clones contained the HaMDR1 vector. Here, we show for the first time real-time polymerase chain reaction based quantification of individual transduced cell clones constituting 0.0008% +/- 0.0003% to 0.0041% +/- 0.00032% of primate peripheral blood cells. No clonal dominance was observed. Disclosure of potential conflicts of interest is found at the end of this article.

Dose Dense Doxorubicin and Cyclophosphamide Followed by Paclitaxel (Dose Dense AC Followed by T) Regimen for Breast Cancer

The increasing complexity of cancer chemotherapy heightens the requirement that pharmacists be familiar with these highly toxic agents. This column will review various issues related to preparation, dispensing, and administration of cancer chemotherapy. It will also serve as a review of various agents, both commercially available and investigational, used to treat malignant diseases.