Predictive Value of ABCC2 and UGT1A1 Polymorphisms on Irinotecan-Related Toxicities in Patients with Cancer.

Background: There is extensive interindividual variability in response and tolerance to anticancer drugs. This heterogeneity provides a major limitation to the "rational" use of cytotoxic drugs, and it becomes a major problem in oncology giving a narrow therapeutic window with a vital risk. Among these anticancer drugs, irinotecan can cause dose-limiting toxicities, commonly diarrhea and neutropenia. Interaction among pathways of activation/inactivation (UGT1A1) and hepatobiliary transport of irinotecan and its metabolites could, in part, explain its interindividual variability. The objective of this study was to perform an exploratory analysis to evaluate the correlation between the genetic polymorphisms of UGT1A1 and ABCC2 with the different toxicities associated with irinotecan treatment. Materials and Methods: Seventy-five patients with solid cancers were included, all were administered an irinotecan-based regimen in both Mission Bay Medical Center; and Zuckerberg San Francisco General Hospital from May 2016 to December 2016. The patients' genotyping was performed for both the UGT1A1*28 polymorphism, and the ABCC2 - 1549G>A, and ABCC2 - 1249G>A single nucleotide polymorphism. Comparisons among qualitative data were assessed using the χ2-test, and Fisher's exact test in the case of small group sizes. Results: Diarrhea was observed in 40 patients (53.3%), among them only 9 patients had high grades diarrhea (grades III and IV). Grades III/IV of nausea were more frequently associated with the ABCC2-1549 AA genotype (83.3% p = 0.004) in patients with colorectal cancer. In pancreatic cancer, a significant absence of diarrhea grades III-IV was noted in patients with the ABCC2 1249 GG genotype compared to the other ABCC2 1249 genotypes.

Development of an LC-MS/MS Method for Measurement of Irinotecan and Its Major Metabolites in Plasma: Technical Considerations.

OBJECTIVE: Irinotecan (CPT-11) is an important drug used in the treatment of several solid tumor types. To minimize its toxicity, therapeutic drug monitoring of CPT-11 and its major metabolites (SN-38, SN-38-glucuronide [SN-38G], and APC) has been proposed. We aimed to develop a liquid chromatography-tandem mass spectrometry (LC-MS/MS) method for the quantification of CPT-11 and its major metabolites in plasma. METHODS: Specimen preparation consisted of protein precipitation, evaporation, and reconstitution. Analyses were performed on a C18 column using reverse-phase gradient elution. Electrospray ionization and multiple reaction monitoring in positive mode were used for MS. The following heavy isotope-labeled internal standards were used: CPT-11 D10, SN-38 D3, SN-38G D3, and APC D3. RESULTS: We found that CPT-11, SN-38G, and APC eluted at ~4.6 to 4.7 minutes, and SN-38 eluted at ~5.1 to 5.2 minutes. A second peak for SN-38 was detected at ~4.6 to 4.7 minutes. Given that the structure of SN-38 is found in CPT-11, SN-38G, and APC, and in the CPT-11 D10 used here, in-source fragmentation was the likely cause. In addition, we found that a low-level SN-38 impurity was present in CPT-11 D10 and to a lesser extent in SN-38 D3. CONCLUSION: When developing methods for CPT-11 and its metabolites, it is important to consider the effects of in-source fragmentation and the choice of internal standards.

Therapeutic Characteristics, Chemotherapy-Related Toxicities and Survivorship in Colorectal Cancer Patients.

BACKGROUND: Colorectal Cancer (CRC) is a major health problem around the globe. In Morocco, the disease ranks third after breast and lung cancers. This study is the first in Morocco to investigate epidemiological, clinical and therapeutic features while exhaustively describing toxic side-effects to chemotherapy of CRC and studying the 3-years survivorship. METHODS: This is a descriptive and analytical retrospective study of about 290 patients with CRC enrolled during the period of January-December 2013. Statistical analysis was performed to correlate clinicopathological data with chemotherapy toxicity and survivorship in patients, by Chi2 test. Overall Survival (OS) rate has been calculated by the Kaplan-Meier method and compared using Log-rank test. RESULTS: Fifty-five percent had a tumor localized in rectum, and 42,8% in colon. Mean age of these patients at diagnosis was 56,16 ± 14,6. incidence rate of adverse events (grade I to IV) was 85,6%. Diarrhea was the predominant toxicity (4.6%) occurring at a high grade (grade III-IV).The 3-years OS rate of patients with CRC was 71%. OS decreased by age, and patients with age subgroup between 40 to 59 years had a better OS than the other age subgroups (60 to 79 years and >80 years) with a p-value of 0.0001. Occurence of toxicity (all grades and types) was linked to a higher survival rates compared to the group who had no toxicity noticed (p-value of 0.001). CONCLUSION: Our study shows that patients who had a polychemotherapy had a better OS than those who had monotherapy (p-value of 0.002).

Inflammatory Breast Cancer: A Literature Review.

The multidisciplinary management of inflammatory breast cancer (IBC), which is the most aggressive form of breast cancer due to its rapid proliferation, has changed over the past three decades thanks to advances in medical treatments that represent the basis of treatment, without eliminating the use of locoregional treatments including surgery and radiotherapy in the localized stages. The molecular profile determination of IBC allows the orientation towards new targeted therapeutic strategies with an impact on survival.