Chemotherapy intensity and toxicity among black and white women with advanced and recurrent endometrial cancer: a Gynecologic Oncology Group Study

Single-nuclei sequencing of uterine serous carcinoma reveals racial differences in immune signaling

Significant racial disparities exist between Black and White patients with uterine serous carcinoma (USC). While the reasons for these disparities are unclear, several studies have demonstrated significantly different rates of driver mutations between racial groups, including TP53. However, limited research has investigated the transcriptional differences of tumors or the composition of the tumor microenvironment (TME) between these groups. Here, we report the single-nuclei RNA-sequencing profiles of primary USC tumors from diverse racial backgrounds. We find that there are significant differences between the tumors of Black and White patients. Tumors from Black patients exhibited higher expression of specific genes associated with aggressiveness, such as PAX8, and axon guidance and synaptic signaling pathways. We also demonstrated that T cell populations are reduced in the tumor tissue compared to matched benign, while anti-inflammatory macrophage populations are retained within the TME. Furthermore, we investigated the connection between PAX8 overexpression and immunosuppression in USC through regulation of several cytokines and chemokines. Notably, we show that PAX8 activity can influence macrophage gene expression and protein secretion. These studies provide a detailed understanding of the USC transcriptome and TME, and identify differences in tumor biology from patients of different racial backgrounds.

Study Protocol for the Social Interventions for Support During Treatment for Endometrial Cancer and Recurrence (SISTER) study: a community engaged national randomized trial

Aim: Social isolation in cancer patients is correlated with prognosis and is a potential mediator of treatment completion. Black women with endometrial cancer (EC) are at increased risk for social isolation when compared with White patients. We developed the Social Interventions for Support during Treatment for Endometrial Cancer and Recurrence (SISTER) study to compare and evaluate interventions to address social isolation among Black women with high-risk EC in USA. The primary objective of the SISTER study is to determine whether virtual support interventions improve treatment completion compared with Enhanced Usual Care. Secondary objectives include comparing effectiveness virtual evidence-based interventions and evaluating barriers and facilitators to social support delivery. Patients & methods: This is a multi-site prospective, open-label, community-engaged randomized controlled trial, consisting of three intervention arms: enhanced usual care, facilitated support group and one-to-one peer support. Primary outcome will be measured using relative dose. Qualitative semi-structured interviews will be conducted with a subset of participants to contextualize the relative degree or lack thereof of social isolation, over time. Data analysis: Primary analysis will be based on an intent-to-treat analysis. Multivariable analysis will be performed to determine the effect of the intervention on the primary and secondary outcomes of interest, relative dose and social isolation score. Semi-structured interviews will be qualitatively analyzed using inductive and deductive approaches of content analysis. Discussion/conclusion: Endometrial cancer mortality disproportionately affects Black women, and social isolation contributes to this disparity. The SISTER study aims to identify whether and to what extent differing social support vehicles improve key outcomes for Black women in the United States with high-risk EC. Clinical Trial Registration: NCT04930159 (ClinicalTrials.gov).

TP53 mutation and abnormal p53 expression in endometrial cancer: Associations with race and outcomes

OBJECTIVE

This multi-center cohort study assessed associations between race, TP53 mutations, p53 expression, and histology to investigate racial survival disparities in endometrial cancer (EC).

METHODS

Black and White patients with advanced or recurrent EC with Next Generation Sequencing data in the Endometrial Cancer Molecularly Targeted Therapy Consortium database were identified. Clinicopathologic and treatment variables were summarized by race and compared. Overall survival (OS) and progression-free survival (PFS) among all patients were estimated by the Kaplan-Meier method. Cox proportional hazards models estimated the association between race, TP53 status, p53 expression, histology, and survival outcomes.

RESULTS

Black patients were more likely than White patients to have TP53-mutated (N = 727, 71.7% vs 49.7%, p < 0.001) and p53-abnormal (N = 362, 71.1% vs 53.2%, p = 0.003) EC. Patients with TP53-mutated EC had worse PFS (HR 2.73 (95% CI 1.88-3.97)) and OS (HR 2.20 (95% CI 1.77-2.74)) compared to those with TP53-wildtype EC. Patients with p53-abnormal EC had worse PFS (HR 2.01 (95% CI 1.22-3.32)) and OS (HR 1.61 (95% CI 1.18-2.19)) compared to those with p53-wildtype EC. After adjusting for TP53 mutation and p53 expression, race was not associated with survival outcomes. The most frequent TP53 variants were at nucleotide positions R273 (n = 54), R248 (n = 38), and R175 (n = 23), rates of which did not differ by race.

CONCLUSIONS

Black patients are more likely to have TP53-mutated and p53-abnormal EC, which are associated with worse survival outcomes than TP53- and p53-wildtype EC. The higher frequency of these subtypes among Black patients may contribute to survival disparities.

Health Disparities in Uterine Cancer: Report From the Uterine Cancer Evidence Review Conference

The Centers for Disease Control and Prevention recognized the need for educational materials for clinicians on the prevention and early diagnosis of gynecologic cancers. The American College of Obstetricians and Gynecologists convened a panel of experts in evidence review from the Society for Academic Specialists in General Obstetrics and Gynecology and content experts from the Society of Gynecologic Oncology to review relevant literature, best practices, and existing practice guidelines for the development of evidence-based educational materials for women's health care clinicians about uterine cancer. This article is the evidence summary of the literature review of health disparities and inequities related to uterine cancer. Substantive knowledge gaps are noted and summarized to provide guidance for future research.

MicroRNA profiling in a case-control study of African American women with uterine serous carcinoma

OBJECTIVE

Uterine serous carcinoma (USC) is an aggressive subtype of endometrial cancer associated with worse survival outcomes in African American (AA) patients. This study evaluated tumor miRNA expression by race, clinical and tumor characteristics, and survival outcomes.

METHODS

FFPE tumor tissue from hysterectomy specimens was identified for 29 AA cases. Case matching was performed by computer-based random assignment in a 1:1 ratio with Caucasian controls based on age, stage and histologic subtype (pure vs. mixed). RNA was extracted from 77 specimens (54 tumors and 23 matched normal endometrium). MicroRNA array profiling was performed by microRNA Hi-Power Labeling (Hy3/Hy5) and hybridization to miRCURY LNA microRNA Array 7th Gen.

RESULTS

Clinical and treatment characteristics were similar for cases and controls, although use of adjuvant radiation was less common in African Americans (p = 0.03). Of 968 miRNAs analyzed, 649 were differentially expressed in normal endometrium vs. tumor. When compared by race, histologic subtype, stage or presence of LVI, no differentially expressed miRNAs were identified. In patients with disease recurrence at 3 years, the three most upregulated miRNAs were miR-1, miR-21-5p and miR-223. Of these, increased miR-223 expression (>median) was associated with worse OS (p = 0.0496) in an independent dataset (TCGA dataset) comprising of 140 patients with USC (mixed or pure serous). After adjusting for age, ethnicity and BMI, upregulation of miR-223 remained risk factor for death (adjusted HR 2.87, 95% CI 1.00-8.27).

CONCLUSIONS

MiRNA profiling did not identify biological differences between AA and Caucasian patients with USC. Upregulation of miR-223 may be a prognostic factor in USC.

Racial disparities in survival among women with endometrial cancer in an equal access system

OBJECTIVE

The mortality rate for Black women with endometrial cancer (EC) is double that of White women, although the incidence rate is lower among Black women. Unequal access to care may contribute to this racial disparity. This study aimed to assess whether survival varied between non-Hispanic Black (NHB) and non-Hispanic White (NHW) women with EC in the Military Health System (MHS) which provides equal access care to its beneficiaries despite racial/ethnic background.

METHODS

The study was conducted using data from the U.S. Department of Defense's (DoD) Automated Central Tumor Registry (ACTUR). Study subjects included NHB and NHW women with histologically confirmed and surgically managed EC diagnosed between 1988 and 2013. The study outcome was all-cause death. Overall survival between NHB and NHW women was compared using multivariable Cox modeling.

RESULTS

The study included 144 NHB and 1439 NHW women with EC. Kaplan-Meier curves showed NHB women had worse survival than NHW women (log-rank P < 0.0001). The disparity in survival between NHB and NHW women persisted after adjusting for age, diagnosis period, tumor stage, tumor histology/grade, and adjuvant treatment (HR = 1.64, 95% CI = 1.19 to 2.27). Multivariable analyses stratified by tumor features or treatment showed that the racial disparity was confined to women with low-risk features (stage I/II disease or low-grade EC) or no adjuvant treatment.

CONCLUSION

There were racial differences in overall survival between NHB and NHW women with EC in the MHS equal access healthcare system, suggesting that factors other than access to care may be related to this racial disparity.

Guideline-adherent treatment, sociodemographic disparities, and cause-specific survival for endometrial carcinomas

BACKGROUND

Adherence to National Comprehensive Cancer Network guidelines have been adopted as the standard of care for various cancers and have been cited to have survival benefits. Few studies have examined the association of adherent treatment and endometrial cancer survival among various racial/ethnic groups and socioeconomic statuses.

METHODS

Between January 1, 2006 and December 31, 2015, 83,673 women diagnosed with endometrial carcinomas were identified from the Surveillance, Epidemiology, and End Results database. Descriptive statistics of demographic and clinical characteristics were performed. Cox-proportional hazards models were used to examine the effect on cause-specific survival for adherence to guidelines across racial/ethnic and socioeconomic groups.

RESULTS

Within our sample, 59.5% were treated according to guidelines. Nonadherence to treatment guidelines was significantly associated with decreased survival compared with adherent care (adjusted hazard ratio [HR], 1.59; 95% CI, 1.52-1.67). Being of Black (adjusted HR, 1.41; 95% CI, 1.32-1.51) or Native Hawaiian/Pacific Islander (adjusted HR, 1.44; 95% CI, 1.19-1.73) race/ethnicity compared with White women was significantly associated with worse survival. Being of Asian race/ethnicity (adjusted HR, 0.86, 95% CI, 0.78-0.94) was significantly associated with improved survival compared with White women. Lower neighborhood socioeconomic status was associated with a negative effect on survival relative to women in the highest socioeconomic status category.

CONCLUSIONS

Findings from this study suggest treatment adherence is an independent predictor of improved survival; however, improved survival was not observed equally among all racial/ethnic and socioeconomic status groups.

LAY SUMMARY

The National Comprehensive Cancer Network (NCCN) has developed guidelines for physicians to follow in treating various cancers. Within this study of 83,673 women with endometrial cancer, 59.5% of women were treated according to the NCCN guidelines. The findings suggest following NCCN guidelines for treatment of endometrial cancer improves survival. Black or Native Hawaiian/Pacific Islander race and lower neighborhood socioeconomic status has worse survival rates compared with other groups, indicating the importance of exploring other factors that may shape treatment across racial/ethnic and socioeconomic status groups.

Impact of quality of care on racial disparities in survival for endometrial cancer

BACKGROUND

Black women experience poorer survival compared with white women across all endometrial cancer stages and histologies. The incidence of endometrial cancer is 30% lower in black women compared with white women, yet mortality is 80% higher in black women. Differences in adherence to evidence-based guidelines have been proposed to be major contributors to this disparity.

OBJECTIVES

We examined whether adherence to evidence-based treatment recommendations for endometrial cancer could mitigate survival disparities between black and white women.

STUDY DESIGN

The National Cancer Database was used to identify women with endometrial cancer treated from 2004 through 2016. We established 5 evidence-based quality metrics based on review of primary literature and accepted guidelines: surgical treatment within 6 weeks of diagnosis (Q1), use of minimally invasive surgery (stage I-IIIC; Q2), pelvic nodal assessment (high-risk tumors; Q3), adjuvant radiation (high intermediate risk; Q4), and systemic chemotherapy (stage III-IV; Q5). The rates of 30 and 90 day mortality and 5 year survival were compared between black and white women. To determine the influence of quality on outcomes, we compared outcomes among perfectly adherent black and white women with stage I and III endometrial cancer.

RESULTS

We identified 310,208 women including 35,035 (11.3%) black women and 275,173 (88.3%) white women. Black women were less likely than white women to receive Q1 (65.8 vs 75.6%), Q2 (58.5 vs 72.9%), Q3 (71.3 vs 74.2%), and Q5 (72.7 vs 73.2%) (P < .05 for all). Adherence to each quality metrics was associated with improved survival. Among women with stage I disease, perfect adherence to the relative quality metrics was seen in 53.1% of white and 41.5% of black women. Among perfectly adherent stage I patients, outcomes in black women improved relative to unselected black women; however, they still experienced higher risk of 30 day (adjusted relative risk, 2.25; 95% confidence interval, 1.30-3.90), 90 day (adjusted relative risk, 1.84; 95% confidence interval, 1.23-2.76), and 5 year mortality (adjusted hazard ratio, 1.42; 95% confidence interval, 1.26-1.59) compared with similar white women. Among women with stage III tumors, perfect adherence to the relative quality metrics was seen in 56.6% of white and 44.1% of black women. Perfectly adherent black women with stage III disease had improved outcomes but remained at increased risk of 30 day (adjusted relative risk, 1.86; 95% confidence interval, 1.01-3.44) and 5 year mortality (adjusted hazard ratio, 1.35; 95% confidence interval, 1.22-1.50) compared with white women.

CONCLUSION

Black women are less likely than white women with endometrial cancer to receive evidence-based care. However, receipt of evidence-based care mitigates but does not eliminate racial disparities in outcomes and black women remain at greater risk of death from endometrial cancer.

Endometrial cancer disparities: a race-conscious critique of the literature

Racial disparities in endometrial cancer are stark and have increased over the past decade. While the disparities are well documented, intervention work to address the mortality gap is nonexistent. This review critiques how race has been conceptualized to explain the causes of endometrial cancer disparities, assesses gaps in knowledge production, and proposes new research priorities. Using public health critical race praxis, a research approach for examining racial disparities and knowledge production processes, we reviewed the endometrial cancer disparities literature from 1995 through 2016. Using systematic search methods, 133 unique records were identified and 48 studies critiqued. We found that a narrow definition of race as a purely biological construct is common throughout the literature. This appears to result in an underemphasis on the role of modifiable, nonbiological contributors to racial disparities and a lack of follow-up work to address these contributors. Key knowledge gaps identified were the role of health care systems in early diagnosis, a lack of intervention studies to address persistent treatment inequity by race, and the near absence of qualitative work to understand the perspectives of Black women diagnosed with endometrial cancer. We conclude with an iterative demonstration of the public health critical race praxis and suggest new routes of inquiry to broaden the scope of research priorities to understand and improve the outcomes of Black women with endometrial cancer.

Association of specific PTEN/10q haplotypes with endometrial cancer phenotypes in African-American and European American women

OBJECTIVE

Endometrial carcinoma (EC), the most common gynecologic malignancy in the United States, affects European American (EA) women more frequently than African-American (AA) women. Yet, AA women are more likely to die from EC. Proposed etiologies for this racial disparity, such as socioeconomic status, aggressive, non-endometrioid tumor histology, and comorbid conditions, do not account for the entire disparity experienced by AA women, suggesting an unexplored genetic component. Germline mutations in PTEN cause Cowden syndrome (CS), which increases lifetime risk of endometrial cancer. In addition, somatic PTEN silencing is one of the most common initiating events in sporadic EC. Therefore, we hypothesized that specific PTEN haplotypes in the AA population may directly predispose AA women to unfavorable tumor characteristics when diagnosed with EC.

METHODS

We conducted a case-control association study of germline variations in and around the PTEN/10q region between 53 EA and 51 AA EC cases and ethnic controls.

RESULTS

Eighteen tag SNPs with minor allele frequency ≥0.1, were genotyped and used to reconstruct haplotypes. Forty-eight ancestry informative markers were genotyped control for population stratification. Two haplotypes were overrepresented in AA, and there was a trend towards tumors with higher stage and grade in patients with these haplotypes. One haplotype was overrepresented in the EA population with a trend towards more endometrioid tumors.

CONCLUSIONS

We show that specific PTEN/10q haplotypes are significantly different between EA and AA individuals (p≤0.02), and specific haplotypes may increase the risk of unfavorable tumor phenotypes in AA women diagnosed with EC.

Disparities in uterine cancer epidemiology, treatment, and survival among African Americans in the United States

OBJECTIVE

The objective of this article is to comprehensively review the scientific literature and summarize the available data regarding the outcome disparities of African American women with uterine cancer.

METHODS

Literature on disparities in uterine cancer was systematically reviewed using the PubMed search engine. Articles from 1992 to 2012 written in English were reviewed. Search terms included endometrial cancer, uterine cancer, racial disparities, and African American.

RESULTS

Twenty-four original research articles with a total of 366,299 cases of endometrial cancer (337,597 Caucasian and 28,702 African American) were included. Compared to Caucasian women, African American women comprise 7% of new endometrial cancer cases, while accounting for approximately 14% of endometrial cancer deaths. They are diagnosed with later stage, higher-grade disease, and poorer prognostic histologic types compared to their Caucasian counterparts. They also suffer worse outcomes at every stage, grade, and for every histologic type. The cause of increased mortality is multifactorial. African American and white women have varying incidence of comorbid conditions, genetic susceptibility to malignancy, access to care and health coverage, and socioeconomic status; however, the most consistent contributors to incidence and mortality disparities are histology and socioeconomics. More robust genetic and molecular profile studies are in development to further explain histologic differences.

CONCLUSIONS

Current studies suggest that histologic and socioeconomic factors explain much of the disparity in endometrial cancer incidence and mortality between white and African American patients. Treatment factors likely contributed historically to differences in mortality; however, studies suggest most women now receive equal care. Molecular differences may be an important factor to explain the racial inequities. Coupled with a sustained commitment to increasing access to appropriate care, on-going research in biologic mechanisms underlying histopathologic differences will help address and reduce the number of African American women who disproportionately suffer and die from endometrial malignancy.

Transcript expression in endometrial cancers from Black and White patients

OBJECTIVE

Previous studies suggest that differences in molecular features of endometrial cancers between racial groups may contribute to the poorer survival in Blacks. The objective of this investigation was to determine whether gene expression among endometrial cancers is different between Blacks and Whites.

METHODS

Fresh frozen tumors from 25 Black patients were matched by stage, grade, and histology to endometrial cancer specimens from 25 White patients. Each case was macrodissected to produce specimens possessing a minimum of 75% cancer cellularity. A subset of 10 matched pairs was also prepared using laser microdissection (LMD) to produce specimens possessing a minimum of 95% cancer cells. Total RNA isolated from each sample was analyzed using the Affymetrix Human Genome U133 Plus 2.0 arrays. Data were analyzed using principal component analysis and binary class comparison analyses.

RESULTS

Unsupervised analysis of the 50 endometrial cancers failed to identify global gene expression profiles unique to Black or White patients. In a subset analysis of 10 matched pairs from Blacks and Whites prepared using LMD and macrodissection, unsupervised analysis did not reveal a unique gene expression profile associated with race in either set, but associations were identified that relate to sample preparation technique, histology and stage.

CONCLUSIONS

Our microarray data revealed no global gene expression differences and identified few individual gene differences between endometrial cancers from Blacks and Whites. More comprehensive methods of transcriptome analysis could uncover RNAs that may underpin the disparity of outcome or prevalence of endometrial cancers in Blacks and Whites.

Racial differences in oncogene mutations detected in early-stage low-grade endometrial cancers

OBJECTIVE

To describe the pattern and frequency of oncogene mutations in white and African American women with endometrial cancer and to determine if racial differences in oncogene mutations exist among women with pathologically similar tumors.

METHODS

Patients with endometrial cancer from a large urban hospital were identified through medical records, and representative formalin-fixed paraffin-embedded tumor blocks were retrieved. The study sample included 150 patients (84 African Americans) who underwent total abdominal hysterectomy for endometrial cancer. The Sequenom MassARRAY system and the OncoCarta Assay version 1.0 (Sequenom) were used to test for 238 mutations in 19 common oncogenes. The χ(2) test and the Fisher exact test were used to assess differences in distribution of variables by race and oncogene mutation status.

RESULTS

There were 20 mutations identified in 2 oncogenes (PIK3CA and KRAS) in tumors from 19 women (12.7%). Most of the mutations were found in PIK3CA (16/20). Thirteen percent of endometrioid tumors harbored mutations (11 PIK3CA and 2 KRAS) as did 29% of the malignant mixed Mullerian tumors (3 PIK3CA and 1 KRAS). There were no observed mutations in serous, clear cell, or mucinous tumor types. Among low-grade endometrioid cancers, tumors from African American patients were significantly associated with harboring either a KRAS or PIK3CA mutation (P = 0.04), with 7 PIK3CA mutations and all 4 KRAS mutations identified in African American women.

CONCLUSIONS

This study provides preliminary evidence that oncogene mutation frequency of some subtypes of histologically similar endometrial carcinoma differ by race. Additional studies are needed to further explore this phenomenon in patients with endometrial carcinoma.

Anthracycline-based chemotherapy in metastatic endometrial carcinoma: an update

The purpose of this review is to analyze clinical evidence about the activity and efficacy of anthracycline-based chemotherapy in metastatic endometrial cancer and to identify the most important preclinical findings that would address future clinical trials. A literature search of published studies was undertaken. Studies were selected by predefined criteria. Clinical trials and preclinical studies were analyzed. The search identified eight phase 3 and 13 phase 2 clinical trials of patients with metastatic endometrial carcinoma treated with an anthracycline-based regimen. The planned dose intensity of the anthracycline had no effect on response rates and survival. Survival increased for patients with a good performance status, and sometimes the duration of responses to anthracycline monotherapy can be very long-lasting. The major findings of anthracycline resistance in preclinical models are reported. Possible future biomarkers targeting mechanisms of anthracycline resistance are suggested, and efforts to define a molecular classification of endometrial cancer are desirable.

Can population differences in chemotherapy outcomes be inferred from differences in pharmacogenetic frequencies?

Inter-ethnic differences in drug handling and frequencies of pharmacogenetic variants are increasingly being characterized. In this study, we systematically assessed the feasibility of inferring ethnic trends in chemotherapy outcomes from inter-ethnic differences in pharmacogenetic variant frequencies. Frequencies of 51 variants and chemotherapy outcomes of East Asian and Caucasian colorectal cancer patients on standard chemotherapy regimens were summarized by meta-analyses, and variant frequencies were validated by MassARRAY analysis. Inferences of relative chemotherapy outcomes were made by considering minor allele function and population differences in their frequency. Significant population differences in genotype distributions were observed for 13/23 (60%) and 27/35 (77%) variants in the meta-analyses and validation series, respectively. Across chemotherapy regimens, East Asians had lower rates of grade 3/4 toxicity for diarrhea and stomatitis/mucositis than Caucasians, which was correctly inferred from 13/18 (72%, P=0.018) informative genetic variants. With appropriate variant selection, inferring relative population toxicity rates from population genotype differences may be relevant.

Racial disparities in histopathologic characteristics of uterine cancer are present in older, not younger blacks in an equal-access environment

OBJECTIVE

We sought to determine whether racial disparities in tumor characteristics among uterine cancer patients persisted, and varied by age, in an equal-access healthcare population.

METHODS

The distributions of tumor histology, stage and grade by race were compared for uterine cancers diagnosed from 1990 to 2003 using data from the U.S. Department of Defense's Automated Central Tumor Registry. Comparisons were conducted overall and stratified by age (<50, ≥50) using the Chi-square test.

RESULTS

Of 2582 uterine tumors identified, 2057 (79.7%) were diagnosed among White women and 183 (7.1%) among Black women. Among all women analyzed, Blacks were more likely than Whites to present with non-endometrioid tumors (47.7% vs 23.5%, p<0.01), non-localized tumors (31.8% vs 24.5%, p=0.02), and poorly differentiated tumors (20.5% vs 15.0%, p<0.01). Among women 50 years and older, similar significant racial disparities were observed. However, no significant racial differences were observed among young patients. When comparisons were restricted to endometrioid histology adenocarcinomas, trends in age-specific disparities for older women were observed.

CONCLUSIONS

Our study suggests that racial disparities in uterine cancers persist between Blacks and Whites in an equal-access population. Blacks endure higher stage and grade tumors, and more aggressive histologies. This disparity in clinicopathologic factors is confined to women older than 50 years. Multiple factors such as racial variation in age-related health knowledge/behavior and estrogen metabolism may be related to the racial disparity.

An update on ethnic differences in drug metabolism and toxicity from anti-cancer drugs

INTRODUCTION

Based on recent emerging evidence of inter-ethnic differences in drug response and toxicity, ethnic diversity in pharmacokinetics, pharmacogenomics and clinical outcomes are being increasingly investigated. Ultimately, this will promote improved understanding of inter-individual differences in the pharmacokinetics and tolerance of cytotoxic drugs.

AREAS COVERED

This article reviews potential explanations for the observed ethnic differences in treatment outcomes and provides clinical data to support this concept. A literature search was implemented on PubMed and PharmGKB to investigate the areas of ethnic differences in pharmacogenomics, pharmacogenetics and clinical outcomes of cancer therapies.

EXPERT OPINION

There has been a relative paucity of clinical evidence linking genetic polymorphisms of genes encoding drug-metabolizing enzymes to the pharmacokinetics, pharmacodynamics and tolerance of anti-cancer drugs. Future research should focus on studies using large sample sizes, in the hope that they will provide results of high clinical significance. Due to the potential for ethnic differences to impact on both toxicities and benefits of systemic cancer therapies, the development of new therapeutic agents should include patients from diverse geographical ancestries in each phase of drug development.