Helping ourselves, helping others: the Young Women's Breast Cancer Study (YWS) - a multisite prospective cohort study to advance the understanding of breast cancer diagnosed in women aged 40 years and younger.

PURPOSE: Compared with older women diagnosed with breast cancer, younger women are more likely to die of breast cancer and more likely to suffer psychosocially in both the short-term and long term. The Young Women's Breast Cancer Study (YWS) is a multisite prospective cohort study established to address gaps in our knowledge about this vulnerable and understudied population. PARTICIPANTS: The YWS enrolled 1302 women newly diagnosed with stages 0-IV breast cancer at age 40 years or younger at 13 academic and community sites in North America between 2006 and 2016. Longitudinal patient-reported outcome data are complemented by clinical data abstraction and biospecimen collection at multiple timepoints. FINDINGS TO DATE: Key findings related to fertility include that nearly 40% of participants were interested in pregnancy following diagnosis; of those who reported interest, 10% pursued fertility preservation. Overall, approximately 10% of YWS participants became pregnant in the first 5 years after diagnosis; follow-up is ongoing for pregnancies after 5 years. Studies focused on psychosocial outcomes have characterised quality of life, post-traumatic stress and fear of recurrence, with findings detailing the factors associated with the substantial psychosocial burden many young women face during and following active treatment. Multiple studies have leveraged YWS biospecimens, including whole-exome sequencing of tumour analyses that revealed that select somatic alterations occur at different frequencies in young (age≤35) versus older women with luminal A breast cancer, and a study that explored clonal hematopoiesis of indeterminate potential found it to be rare in young survivors. FUTURE PLANS: With a median follow-up of approximately 10 years, the cohort is just maturing for many relevant long-term outcomes and provides outstanding opportunities to further study and build collaborations to address gaps in our knowledge, with the ultimate objective to improve care and outcomes for young women with breast cancer. TRIAL REGISTRATION NUMBER: NCT01468246.

Second primary non-breast cancers in young breast cancer survivors.

PURPOSE: We evaluated the incidence, timing, and risk factors for second primary non-breast cancers (SPNBC) among young breast cancer (BC) survivors. METHODS: This study included participants of the Young Women's BC Study (YWS) who were diagnosed with stage 0-III BC between 2006 and 2016 and age 40 or younger at diagnosis (N = 1,230). Patient characteristics, treatment information, and clinical events were collected via serial surveys. Tumor and treatment data were obtained from medical record review. Five- and 10-year risks of SPNBCs were estimated via the cumulative incidence function, considering death, metastasis, or second primary BC as competing events. Fine and Gray subdistribution hazard models estimated subdistribution hazard ratios (sHRs) and 95% confidence intervals (CI) for SPNBC risk based on risk factors including demographics, germline genetics, primary BC characteristics, and treatments. RESULTS: Among 1,230 women, over a median follow-up of 10.1 years, 47 patients (4%) developed an SPNBC. Types of malignancy included melanoma (n = 10), thyroid (n = 10), ovarian (n = 4), sarcoma (n = 4), uterine (n = 3), rectal (n = 3), bladder (n = 2), cervical (n = 2), head/neck (n = 2), lung (n = 2), lymphoma (n = 2), pancreatic (n = 2), and renal (n = 1). Five and 10-year cumulative incidence were 1.4% and 3.2%, respectively. Median time between primary BC and SPNBC was 7.3 years. No patient factors, primary tumor characteristics, or treatments were statistically significantly associated with SPNBC in univariable or multivariable models. CONCLUSION: In this population, five-year cumulative incidence was higher than that reported among healthy women under 50 years of age, highlighting the importance of long-term surveillance for new non-breast cancers in young adult BC survivors.

Clinicogenomic characterization of inflammatory breast cancer.

Background: Inflammatory breast cancer (IBC) is a rare and poorly characterized type of breast cancer with an aggressive clinical presentation. The biological mechanisms driving the IBC phenotype are relatively undefined-partially due to a lack of comprehensive, large-scale genomic studies and limited clinical cohorts. Patients and Methods: A retrospective analysis of 2457 patients with metastatic breast cancer who underwent targeted tumor-only DNA-sequencing was performed at Dana-Farber Cancer Institute. Clinicopathologic, single nucleotide variant (SNV), copy number variant (CNV) and tumor mutational burden (TMB) comparisons were made between clinically confirmed IBC cases within a dedicated IBC center versus non-IBC cases. Results: Clinicopathologic differences between IBC and non-IBC cases were consistent with prior reports-including IBC being associated with younger age at diagnosis, higher grade, and enrichment with hormone receptor (HR)-negative and HER2-positive tumors. The most frequent somatic alterations in IBC involved TP53 (72%), ERBB2 (32%), PIK3CA (24%), CCND1 (12%), MYC (9%), FGFR1 (8%) and GATA3 (8%). A multivariate logistic regression analysis revealed a significant enrichment in TP53 SNVs in IBC; particularly in HER2-positive and HR-positive disease which was associated with worse outcomes. Tumor mutational burden (TMB) did not differ substantially between IBC and non-IBC cases and a pathway analysis revealed an enrichment in NOTCH pathway alterations in HER2-positive disease. Conclusion: Taken together, this study provides a comprehensive, clinically informed landscape of somatic alterations in a large cohort of patients with IBC. Our data support higher frequency of TP53 mutations and a potential enrichment in NOTCH pathway activation-but overall; a lack of major genomic differences. These results both reinforce the importance of TP53 alterations in IBC pathogenesis as well as their influence on clinical outcomes; but also suggest additional analyses beyond somatic DNA-level changes are warranted.

Second Primary Breast Cancer in Young Breast Cancer Survivors.

Importance: Among women diagnosed with primary breast cancer (BC) at or younger than age 40 years, prior data suggest that their risk of a second primary BC (SPBC) is higher than that of women who are older when they develop a first primary BC. Objective: To estimate cumulative incidence and characterize risk factors of SPBC among young patients with BC. Design, Setting, and Participants: Participants were enrolled in the Young Women's Breast Cancer Study, a prospective study of 1297 women aged 40 years or younger who were diagnosed with stage 0 to III BC from August 2006 to June 2015. Demographic, genetic testing, treatment, and outcome data were collected by patient surveys and medical record review. A time-to-event analysis was used to account for competing risks when determining cumulative incidence of SPBC, and Fine-Gray subdistribution hazard models were used to evaluate associations between clinical factors and SPBC risk. Data were analyzed from January to May 2023. Main Outcomes and Measures: The 5- and 10- year cumulative incidence of SPBC. Results: In all, 685 women with stage 0 to III BC (mean [SD] age at primary BC diagnosis, 36 [4] years) who underwent unilateral mastectomy or lumpectomy as the primary surgery for BC were included in the analysis. Over a median (IQR) follow-up of 10.0 (7.4-12.1) years, 17 patients (2.5%) developed an SPBC; 2 of these patients had cancer in the ipsilateral breast after lumpectomy. The median (IQR) time from primary BC diagnosis to SPBC was 4.2 (3.3-5.6) years. Among 577 women who underwent genetic testing, the 10-year risk of SPBC was 2.2% for women who did not carry a pathogenic variant (12 of 544) and 8.9% for carriers of a pathogenic variant (3 of 33). In multivariate analyses, the risk of SPBC was higher among PV carriers vs noncarriers (subdistribution hazard ratio [sHR], 5.27; 95% CI, 1.43-19.43) and women with primary in situ BC vs invasive BC (sHR, 5.61; 95% CI, 1.52-20.70). Conclusions: Findings of this cohort study suggest that young BC survivors without a germline pathogenic variant have a low risk of developing a SPBC in the first 10 years after diagnosis. Findings from germline genetic testing may inform treatment decision-making and follow-up care considerations in this population.

Circulating Tumor DNA and Late Recurrence in High-Risk Hormone Receptor-Positive, Human Epidermal Growth Factor Receptor 2-Negative Breast Cancer.

PURPOSE: To examine the prevalence and dynamics of circulating tumor DNA (ctDNA) and its association with metastatic recurrence in patients with high-risk early-stage hormone receptor-positive breast cancer (HR+ BC) more than 5 years from diagnosis. METHODS: We enrolled 103 patients with high-risk stage II-III HR+ BC diagnosed more than 5 years prior without clinical evidence of recurrence. We performed whole-exome sequencing (WES) on primary tumor tissue to identify somatic mutations tracked via a personalized, tumor-informed ctDNA test to detect minimal residual disease (MRD). We collected plasma at the time of consent and at routine visits every 6-12 months. Patients were followed for clinical recurrence. RESULTS: In total, 85 of 103 patients had sufficient tumor tissue; of them, 83 of 85 (97.6%) patients had successful whole-exome sequencing. Personalized ctDNA assays were designed targeting a median of 36 variants to test 219 plasma samples. The median time from diagnosis to first sample was 8.4 years. The median follow-up was 10.4 years from diagnosis and 2.0 years from first sample. The median number of plasma samples per patient was two. Eight patients (10%) had positive MRD testing at any time point. Six patients (7.2%) developed distant metastatic recurrence, all of whom were MRD-positive before overt clinical recurrence, with median ctDNA lead time of 12.4 months. MRD was not identified in one patient (1.2%) with local recurrence. Two of eight MRD-positive patients had not had clinical recurrence at last follow-up. CONCLUSION: In this prospective study, in patients with high-risk HR+ BC in the late adjuvant setting, ctDNA was identified a median of 1 year before all cases of distant metastasis. Future studies will determine if ctDNA-guided intervention in patients with HR+ BC can alter clinical outcomes.

Somatic and Germline Genomic Alterations in Very Young Women with Breast Cancer.

PURPOSE: Young age at breast cancer diagnosis correlates with unfavorable clinicopathologic features and worse outcomes compared with older women. Understanding biological differences between breast tumors in young versus older women may lead to better therapeutic approaches for younger patients. EXPERIMENTAL DESIGN: We identified 100 patients ≤35 years old at nonmetastatic breast cancer diagnosis who participated in the prospective Young Women's Breast Cancer Study cohort. Tumors were assigned a surrogate intrinsic subtype based on receptor status and grade. Whole-exome sequencing of tumor and germline samples was performed. Genomic alterations were compared with older women (≥45 years old) in The Cancer Genome Atlas, according to intrinsic subtype. RESULTS: Ninety-three tumors from 92 patients were successfully sequenced. Median age was 32.5 years; 52.7% of tumors were hormone receptor-positive/HER2-negative, 28.0% HER2-positive, and 16.1% triple-negative. Comparison of young to older women (median age 61 years) with luminal A tumors (N = 28 young women) revealed three significant differences: PIK3CA alterations were more common in older patients, whereas GATA3 and ARID1A alterations were more common in young patients. No significant genomic differences were found comparing age groups in other intrinsic subtypes. Twenty-two patients (23.9%) in the Young Women's Study cohort carried a pathogenic germline variant, most commonly (13 patients, 14.1%) in BRCA1/2. CONCLUSIONS: Somatic alterations in three genes (PIK3CA, GATA3, and ARID1A) occur at different frequencies in young versus older women with luminal A breast cancer. Additional investigation of these genes and associated pathways could delineate biological susceptibilities and improve treatment options for young patients with breast cancer. See related commentary by Yehia and Eng, p. 2209.

Impact of Cancer History on Outcomes Among Hospitalized Patients with COVID-19.

BACKGROUND: Early reports suggested increased mortality from COVID-19 in patients with cancer but lacked rigorous comparisons to patients without cancer. We investigated whether a current cancer diagnosis or cancer history is an independent risk factor for death in hospitalized patients with COVID-19. PATIENTS AND METHODS: We identified patients with a history of cancer admitted to two large hospitals between March 13, 2020, and May 10, 2020, with laboratory-confirmed COVID-19 and matched them 1:2 to patients without a history of cancer. RESULTS: Men made up 56.2% of the population, with a median age of 69 years (range, 30-96). The median time since cancer diagnosis was 35.6 months (range, 0.39-435); 80% had a solid tumor, and 20% had a hematologic malignancy. Among patients with cancer, 27.8% died or entered hospice versus 25.6% among patients without cancer. In multivariable analyses, the odds of death/hospice were similar (odds ratio [OR], 1.09; 95% confidence interval [CI], 0.65-1.82). The odds of intubation (OR, 0.46; 95% CI, 0.28-0.78), shock (OR, 0.54; 95% CI, 0.32-0.91), and intensive care unit admission (OR, 0.51; 95% CI, 0.32-0.81) were lower for patients with a history of cancer versus controls. Patients with active cancer or who had received cancer-directed therapy in the past 6 months had similar odds of death/hospice compared with cancer survivors (univariable OR, 1.31; 95% CI, 0.66-2.60; multivariable OR, 1.47; 95% CI, 0.69-3.16). CONCLUSION: Patients with a history of cancer hospitalized for COVID-19 had similar mortality to matched hospitalized patients with COVID-19 without cancer, and a lower risk of complications. In this population, patients with active cancer or recent cancer treatment had a similar risk for adverse outcomes compared with survivors of cancer. IMPLICATIONS FOR PRACTICE: This study investigated whether a current cancer diagnosis or cancer history is an independent risk factor for death or hospice admission in hospitalized patients with COVID-19. Active cancer, systemic cancer therapy, and a cancer history are not independent risk factors for death from COVID-19 among hospitalized patients, and hospitalized patients without cancer are more likely to have severe COVID-19. These findings provide reassurance to survivors of cancer and patients with cancer as to their relative risk of severe COVID-19, may encourage oncologists to provide standard anticancer therapy in patients at risk of COVID-19, and guide triage in future waves of infection.

Sensitive Detection of Minimal Residual Disease in Patients Treated for Early-Stage Breast Cancer.

PURPOSE: Existing cell-free DNA (cfDNA) methods lack the sensitivity needed for detecting minimal residual disease (MRD) following therapy. We developed a test for tracking hundreds of patient-specific mutations to detect MRD with a 1,000-fold lower error rate than conventional sequencing. EXPERIMENTAL DESIGN: We compared the sensitivity of our approach to digital droplet PCR (ddPCR) in a dilution series, then retrospectively identified two cohorts of patients who had undergone prospective plasma sampling and clinical data collection: 16 patients with ER+/HER2- metastatic breast cancer (MBC) sampled within 6 months following metastatic diagnosis and 142 patients with stage 0 to III breast cancer who received curative-intent treatment with most sampled at surgery and 1 year postoperative. We performed whole-exome sequencing of tumors and designed individualized MRD tests, which we applied to serial cfDNA samples. RESULTS: Our approach was 100-fold more sensitive than ddPCR when tracking 488 mutations, but most patients had fewer identifiable tumor mutations to track in cfDNA (median = 57; range = 2-346). Clinical sensitivity was 81% (n = 13/16) in newly diagnosed MBC, 23% (n = 7/30) at postoperative and 19% (n = 6/32) at 1 year in early-stage disease, and highest in patients with the most tumor mutations available to track. MRD detection at 1 year was strongly associated with distant recurrence [HR = 20.8; 95% confidence interval, 7.3-58.9]. Median lead time from first positive sample to recurrence was 18.9 months (range = 3.4-39.2 months). CONCLUSIONS: Tracking large numbers of individualized tumor mutations in cfDNA can improve MRD detection, but its sensitivity is driven by the number of tumor mutations available to track.

Prospective study of family history and colorectal cancer risk by tumor LINE-1 methylation level.

BACKGROUND: Beyond known familial colorectal cancer (CRC) syndromes, the mechanisms underlying the elevated CRC risk associated with CRC family history remain largely unknown. A recent retrospective study suggests familial clustering of CRC with hypomethylation in long interspersed nucleotide element 1 (LINE-1). We tested the hypothesis that CRC family history might confer a higher risk of LINE-1 methylation-low CRC. METHODS: Using the Nurses' Health Study and the Health Professionals Follow-up Study, we prospectively examined the association between CRC family history and the risk of rectal and colon cancer (N = 1224) according to tumor LINE-1 methylation level by duplication method Cox proportional hazards regression. We examined microsatellite instability (MSI) status to exclude the influence of Lynch syndrome. All statistical tests were two-sided. RESULTS: The association between CRC family history and non-MSI CRC risk differed statistically significantly by LINE-1 methylation level (P (heterogeneity) = .02). CRC family history was associated with a statistically significantly higher risk of LINE-1 methylation-low non-MSI cancer (multivariable hazard ratio [HR] = 1.68, 95% confidence interval [CI] = 1.19 to 2.38 for 1 vs 0 first-degree relatives with CRC; multivariable HR = 3.48, 95% CI = 1.59 to 7.6 for ≥2 vs 0 first-degree relatives with CRC; P (trend) < .001). In contrast, CRC family history was not statistically significantly associated with LINE-1 methylation-high non-MSI cancer (P (trend) = .35). CONCLUSIONS: This molecular pathological epidemiology study shows that CRC family history is associated with a higher risk of LINE-1 methylation-low CRC, suggesting previously unrecognized heritable predisposition to epigenetic alterations. Additional studies are needed to evaluate tumor LINE-1 methylation as a molecular biomarker for familial cancer risk assessment.

Expression profiling of archival tumors for long-term health studies.

PURPOSE: More than 20 million archival tissue samples are stored annually in the United States as formalin-fixed, paraffin-embedded (FFPE) blocks, but RNA degradation during fixation and storage has prevented their use for transcriptional profiling. New and highly sensitive assays for whole-transcriptome microarray analysis of FFPE tissues are now available, but resulting data include noise and variability for which previous expression array methods are inadequate. EXPERIMENTAL DESIGN: We present the two largest whole-genome expression studies from FFPE tissues to date, comprising 1,003 colorectal cancer (CRC) and 168 breast cancer samples, combined with a meta-analysis of 14 new and published FFPE microarray datasets. We develop and validate quality control (QC) methods through technical replication, independent samples, comparison to results from fresh-frozen tissue, and recovery of expected associations between gene expression and protein abundance. RESULTS: Archival tissues from large, multicenter studies showed a much wider range of transcriptional data quality relative to smaller or frozen tissue studies and required stringent QC for subsequent analysis. We developed novel methods for such QC of archival tissue expression profiles based on sample dynamic range and per-study median profile. This enabled validated identification of gene signatures of microsatellite instability and additional features of CRC, and improved recovery of associations between gene expression and protein abundance of MLH1, FASN, CDX2, MGMT, and SIRT1 in CRC tumors. CONCLUSIONS: These methods for large-scale QC of FFPE expression profiles enable study of the cancer transcriptome in relation to extensive clinicopathological information, tumor molecular biomarkers, and long-term lifestyle and outcome data.

Germline polymorphisms in the one-carbon metabolism pathway and DNA methylation in colorectal cancer.

Dietary intake of one-carbon nutrients (methyl donors) and germline variants in the one-carbon metabolism genes may influence global DNA methylation level and methylation in promoter CpG islands. In this study, we evaluated the relationship between single nucleotide polymorphisms (SNPs) in the one-carbon metabolism pathway and DNA methylation status in colorectal cancer. Utilizing 182 colorectal cancers cases in two prospective cohort studies, we determined the CpG island methylator phenotype (CIMP) status on eight CIMP-specific promoters and measured LINE-1 methylation level that correlates well with genome-wide DNA methylation level. We genotyped 23 nonsynonymous SNPs in the one-carbon metabolism genes using buffy coat DNA. Most of the 23 SNPs in the one-carbon metabolism pathway were not significantly associated with CIMP-high status (> or = 6/8 methylated promoters). However, the MTHFR 429 Ala/Ala variant (rs1801131) and the TCN2 259 Arg/Arg variant (rs1801198) were associated with CIMP-high status (MTHFR 429 multivariate odds ratio (MV OR) = 7.56; 95% confidence interval (CI), 1.32-43.3; p trend = 0.10; TCN2 259 Arg/Arg variant MV OR = 3.82; 95% CI, 1.02-14.4; p trend = 0.06). The one-carbon metabolism genotypes were not significantly associated with LINE-1 methylation, although there were modest differences in mean LINE-1 methylation levels between certain genotypes. Collectively, these exploratory data provide suggestive evidence for the association of MTHFR 429 Ala/ Ala and TCN2 259 Arg/Arg and CIMP status in colorectal cancer.

Negative lymph node count is associated with survival of colorectal cancer patients, independent of tumoral molecular alterations and lymphocytic reaction.

OBJECTIVES: The number of recovered lymph nodes is associated with good prognosis among colon cancer patients undergoing surgical resection. However, little has been known on prognostic significance of lymph node count after adjusting for host immune response to tumor and tumoral molecular alterations, both of which are associated with the lymph node count and patient survival. METHODS: Among 716 colorectal cancers (stages 1-4) in two independent prospective cohorts, we examined patient survival in relation to the negative lymph node count and lymph node ratio (LNR; positive to total lymph node counts). Cox proportional hazard models were used to compute hazard ratio of deaths, adjusted for patient, specimen, and tumoral characteristics, including lymphocytic reactions, KRAS and BRAF mutations, p53 expression, microsatellite instability (MSI), the CpG island methylator phenotype (CIMP), and LINE-1 methylation. RESULTS: Compared with patients with 0-3 negative lymph nodes, patients with 7-12 and > or =13 negative nodes experienced a significant reduction in cancer-specific and overall mortality in Kaplan-Meier analysis (log-rank P<0.0001), univariate Cox regression (P(trend)<0.0001), and multivariate analysis (P(trend)<0.0003), independent of potential confounders examined. The benefit associated with the negative node count was apparent across all stages, although the effect was significantly greater in stages 1-2 than stages 3-4 (P(interaction)=0.002). In both stage 3 and stage 4, smaller LNR was associated with improved survival (log-rank P<0.0001). CONCLUSIONS: The negative lymph node count is associated with improved survival of colorectal cancer patients, independent of lymphocytic reactions to tumor and tumoral molecular features including MSI, CIMP, LINE-1 hypomethylation and BRAF mutation.

Physical activity and male colorectal cancer survival.

BACKGROUND: Although physically active individuals have a lower risk of developing colorectal cancer, few studies have examined whether exercise benefits colorectal cancer survivors. METHODS: Derived from the Health Professionals Follow-up Study, we studied colorectal cancer-specific and overall mortality in a cohort of 668 men with a history of stage I to stage III colorectal cancer according to predefined physical activity categories after diagnosis. To minimize bias by occult recurrences, we excluded men who died within 6 months of their postdiagnosis physical activity assessment. RESULTS: In a cohort of men with colorectal cancer and no apparent metastases at diagnosis, 50.4% exercised at least 18 metabolic equivalent task (MET) hours per week. Increased physical activity was significantly associated with improved colorectal cancer-specific mortality (P = .002 for trend) and overall mortality (P < .001 for trend). Men who engaged in more than 27 MET hours per week of physical activity had an adjusted hazard ratio for colorectal cancer-specific mortality of 0.47 (95% confidence interval, 0.24-0.92) compared with men who engaged in 3 or less MET hours per week of physical activity. The apparent benefit of physical activity was seen regardless of age, disease stage, body mass index, diagnosis year, tumor location, and prediagnosis physical activity. CONCLUSION: In a large cohort of men with a history of nonmetastatic colorectal cancer, more physical activity was associated with a lower risk of colorectal cancer-specific and overall mortality.

p21 expression in colon cancer and modifying effects of patient age and body mass index on prognosis.

p21 (Cyclin-dependent kinase inhibitor-1A, CDKN1A or CIP1) plays a role in regulating cell cycle, and its expression is lost in most colorectal cancers. p21 Is related with energy balance status, cellular senescence, and stem cell aging. Thus, the influence of p21 loss on tumor behavior and clinical outcome may be modified by patient age and body mass index (BMI). Using 647 colon cancers in two independent prospective cohorts, p21 loss was observed in 509 (79%) tumors by immunohistochemistry. Cox proportional hazard models computed hazard ratio (HR) for death, adjusted for potential confounders, including p53, cyclin D1, KRAS, BRAF, PIK3CA, LINE-1 hypomethylation, CpG island methylator phenotype (CIMP), and microsatellite instability (MSI). p21 Loss was independently associated with low colon cancer-specific mortality [HR, 0.58; 95% confidence interval (95% CI), 0.38-0.89; adjusted for the covariates including MSI, CIMP, and LINE-1 methylation]. The prognostic effect of p21 loss differed significantly by age at diagnosis (P(interaction) < 0.0001) and BMI (P(interaction) = 0.002). The adjusted HR for cancer-specific mortality (p21 loss versus p21 expression) was 4.09 (95% CI, 1.13-14.9) among patients <60 year old and 0.37 (95% CI, 0.24-0.59) among patients >or=60 year old. The adverse prognostic effect of obesity was limited to p21-expressing cases (adjusted HR, 5.85; 95% CI, 2.28-15.0; BMI, >or=30 versus <30 kg/m(2)), but no such effect was observed among p21-lost cases. In conclusion, p21 loss in colon cancer is associated with longer survival among patients >or=60 year old, whereas it is associated with shorter survival among patients <60 year old. Patient BMI also differentially influences prognosis according to p21 CDKN1A status. Our data suggest host-tumor interactions influencing tumor aggressiveness.

Interaction of molecular markers and physical activity on mortality in patients with colon cancer.

PURPOSE: Physical activity in colon cancer survivors has been associated with lower cancer recurrences and improved survival. Whether molecular features of the tumor portend more or less likelihood for benefit from exercise is unknown. EXPERIMENTAL DESIGN: Using two large prospective cohort studies with physical activity assessments after colon cancer diagnosis, we examined expression of fatty acid synthase, p53, p21, and p27 and mutational status of K-ras and phosphatidylinositol 3-kinase(PI3KCA). We calculated hazard ratios (HR) of colon cancer-specific mortality, adjusted for tumor and patient characteristics, and tested for molecular interactions with exercise. RESULTS: In a cohort of 484 men and women with stage I to III colon cancer, patients who engaged in at least 18 metabolic equivalent task (MET)-hours per week after diagnosis had an adjusted HR for colon cancer-specific mortality of 0.64 [95% confidence interval (95% CI), 0.33-1.23] and for overall mortality of 0.60 (95% CI, 0.41-0.86). A statistically significant interaction was detected based on p27 expression (P = 0.03). For tumors with loss of p27 (n = 195), physical activity of > or =18 MET-hours/week led to a HR for colon cancer mortality of 1.40 (95% CI, 0.41-4.72), compared with those with <18 MET-hours/week. However, for tumors with expression of p27 (n = 251), the adjusted HR was 0.33 (95% CI, 0.12-0.85). Molecular status of fatty acid synthase, K-ras, p53, p21, and PI3KCA did not influence the association between exercise and colon cancer-specific or overall mortality. CONCLUSION: The benefit of physical activity on outcomes in patients with stage I to III colon cancer may be influenced by p27 status. Further studies are warranted to confirm these findings.

Prognostic significance and molecular associations of 18q loss of heterozygosity: a cohort study of microsatellite stable colorectal cancers.

PURPOSE: Loss of heterozygosity (LOH) at chromosome 18q frequently occurs late during colon cancer development and is inversely associated with microsatellite instability (MSI). 18q LOH has been reported to predict shorter survival in patients with colorectal cancer, whereas MSI-high status has been associated with superior prognosis. However, it is unclear whether 18q LOH in colorectal cancer has any prognostic implication independent of MSI status and other potential predictors of clinical outcome. PATIENTS AND METHODS: Among 555 non-MSI-high colorectal cancers (stage I to IV) in two independent prospective cohort studies, we examined 18q LOH in relation to other molecular events and patient survival. Cox proportional hazard models computed hazard ratio of death, adjusted for clinical and tumoral characteristics, including KRAS, BRAF, PIK3CA, beta-catenin, p53, CpG island methylator phenotype, LINE-1 methylation, and John Cunningham (JC) virus T antigen. RESULTS: In multivariate logistic regression, 18q LOH was independently associated with JC virus T antigen (odds ratio [OR] = 1.93; P = .0077), body mass index > or = 30 kg/m(2) (obesity; OR = 2.01; P = .014), high tumor grade (OR = 0.40; P = .018), KRAS mutation (OR = 0.66; P = .40), and LINE-1 hypomethylation (for a 30% decrease; OR = 1.92; P = .045). Five-year colorectal cancer-specific survival was 75% among patients with 18q LOH-positive tumors and 74% among those with 18q LOH-negative tumors (log-rank P = .80). Five-year overall survival was 70% among patients with 18q LOH-positive tumors and 68% among those with 18q LOH-negative tumors (log-rank P = .54). Multivariate analysis did not show prognostic significance of 18q LOH. CONCLUSION: In our large prospective study of patients with non-MSI-high colorectal cancer, 18q LOH or allelic imbalance was not associated with patient survival.

A cohort study of STMN1 expression in colorectal cancer: body mass index and prognosis.

OBJECTIVES: STMN1 (stathmin or oncoprotein-18) destabilizes microtubules and reorganizes cytoskeleton, and functions in cell cycle progression and cell migration. STMN1 activity is influenced by p53, p27, and the PI3K/AKT pathway. However, its prognostic significance in colon cancer is uncertain. METHODS: Utilizing 546 colorectal cancers (stage I-IV) from two independent prospective cohort studies (the Nurses' Health Study and Health Professionals Follow-up Study), STMN1 expression was detected in 297 (54%) tumors by immunohistochemistry. Cox proportional hazard models computed hazard ratios (HRs) of mortality, adjusted for clinical and tumoral features, including microsatellite instability (MSI), CpG island methylation phenotype (CIMP), LINE-1 hypomethylation, KRAS, BRAF, PIK3CA, p53, p21, p27, cyclin D1, beta-catenin, fatty acid synthase, FASN, and COX-2. RESULTS: Five-year colorectal cancer-specific survival was 78% in STMN1-positive patients and 76% in STMN1-negative patients (log-rank P=0.30). STMN1-positivity was not significantly associated with cancer-specific survival in univariate analysis with HR of 0.82 (95% confidence interval (CI), 0.59-1.14), which became significant in multivariate analysis (adjusted HR=0.60; 95% CI, 0.41-0.87; P=0.0078). Notably, the prognostic effect of obesity (body mass index, BMI> or =30 kg/m2) significantly differed by STMN1 (P(interaction)=0.005). Obesity was associated with high cancer-specific mortality among STMN1-positive patients (adjusted HR=2.36; 95% CI, 1.18-4.69), whereas obesity was not associated with high mortality among STMN1-negative patients (adjusted HR=0.51; 95% CI, 0.24-1.07). CONCLUSIONS: STMN1 overexpression in colorectal cancer is independently associated with improved survival. The adverse prognostic effect of obesity was limited to patients with STMN1-positive tumors. Our findings suggest the presence of a tumor (STMN1)-host (BMI) interaction that potentially determines clinical outcome.

DNMT3B expression might contribute to CpG island methylator phenotype in colorectal cancer.

PURPOSE: DNA methyltransferase-3B (DNMT3B) plays an important role in de novo CpG island methylation. Dnmt3b can induce colon tumor in mice with methylation in specific CpG islands. We hypothesized that cellular DNMT3B level might influence the occurrence of widespread CpG island methylation (i.e., the CpG island methylator phenotype, CIMP) in colon cancer. EXPERIMENTAL DESIGN: Utilizing 765 colorectal cancers in two cohort studies, we detected DNMT3B expression in 116 (15%) tumors by immunohistochemistry. We assessed microsatellite instability, quantified DNA methylation in repetitive long interspersed nucleotide element-1 (LINE-1) by Pyrosequencing, eight CIMP-specific promoters [CACNA1G, CDKN2A (p16), CRABP1, IGF2, MLH1, NEUROG1, RUNX3, and SOCS1], and eight other CpG islands (CHFR, HIC1, IGFBP3, MGMT, MINT1, MINT31, p14, and WRN) by real-time PCR (MethyLight). RESULTS: Tumoral DNMT3B overexpression was significantly associated with CIMP-high [> or =6/8 methylated CIMP-specific promoters; odds ratio (OR), 3.34; 95% confidence interval, 2.11-5.29; P < 0.0001]. The relations between DNMT3B and methylation in 16 individual CpG islands varied substantially (OR, 0.80-2.96), suggesting variable locus-to-locus specificities of DNMT3B activity. DNMT3B expression was not significantly related with LINE-1 hypomethylation. In multivariate logistic regression, the significant relation between DNMT3B and CIMP-high persisted (OR, 2.39; 95% confidence interval, 1.11-5.14; P = 0.026) after adjusting for clinical and other molecular features, including p53, beta-catenin, LINE-1, microsatellite instability, KRAS, PIK3CA, and BRAF. DNMT3B expression was unrelated with patient outcome, survival, or prognosis. CONCLUSIONS: Tumoral DNMT3B overexpression is associated with CIMP-high in colorectal cancer. Our data support a possible role of DNMT3B in nonrandom de novo CpG island methylation leading to colorectal cancer.

Aurora-A expression is independently associated with chromosomal instability in colorectal cancer.

AURKA (the official symbol for Aurora-A, STK15, or BTAK) regulates the function of centrosomes, spindles, and kinetochores for proper mitotic progression. AURKA overexpression is observed in various cancers including colon cancer, and a link between AURKA and chromosomal instability (CIN) has been proposed. However, no study has comprehensively examined AURKA expression in relation to CIN or prognosis using a large number of tumors. Using 517 colorectal cancers in two prospective cohort studies, we detected AURKA overexpression (by immunohistochemistry) in 98 tumors (19%). We assessed other molecular events including loss of heterozygosity (LOH) in 2p, 5q, 17q, and 18q, the CpG island methylation phenotype (CIMP), and microsatellite instability (MSI). Prognostic significance of AURKA was evaluated by Cox regression and Kaplan-Meier method. In both univariate and multivariate logistic regressions, AURKA overexpression was significantly associated with CIN (defined as the presence of LOH in any of the chromosomal segments; multivariate odds ratio, 2.97; 95% confidence interval, 1.40-6.29; P = .0045). In multivariate analysis, AURKA was associated with cyclin D1 expression (P = .010) and inversely with PIK3CA mutation (P=.014), fatty acid synthase expression (P=.028), and family history of colorectal cancer (P = .050), but not with sex, age, body mass index, tumor location, stage, CIMP, MSI, KRAS, BRAF, BMI, LINE-1 hypomethylation, p53, p21, beta-catenin, or cyclooxygenase 2. AURKA was not significantly associated with clinical outcome or survival. In conclusion, AURKA overexpression is independently associated with CIN in colorectal cancer, supporting a potential role of Aurora kinase-A in colorectal carcinogenesis through genomic instability (rather than epigenomic instability).

PIK3CA mutation is associated with poor prognosis among patients with curatively resected colon cancer.

PURPOSE: PIK3CA mutation and subsequent activation of the AKT pathway play an important role in colorectal carcinogenesis. However, little is known about the prognostic role of PIK3CA mutation in colon cancer. PATIENTS AND METHODS: Using 450 resectable colon cancers (stage I to III) in two independent prospective cohorts, we detected PIK3CA mutation in 82 tumors (18%) by pyrosequencing. Cox proportional hazards models were used to calculate hazard ratios (HRs) of colon cancer-specific and overall mortalities, adjusted for patient characteristics and tumoral molecular features, including the CpG island methylation phenotype, microsatellite instability (MSI), LINE-1 hypomethylation, and p53, CIMP, KRAS and BRAF mutation. RESULTS: Compared with patients with PIK3CA wild-type tumors, those with PIK3CA-mutated tumors experienced an increase in colon cancer-specific mortality according to univariate analysis (HR = 1.64; 95% CI, 0.95 to 2.86), which persisted after adjusting for other known or potential risk factors for cancer recurrence (including MSI; multivariate HR = 2.23; 95% CI, 1.21 to 4.11). The effect of PIK3CA mutation on cancer survival seemed to differ according to KRAS mutational status. Among patients with KRAS wild-type tumors, the presence of PIK3CA mutation was associated with a significant increase in colon cancer-specific mortality (HR = 3.80; 95% CI, 1.56 to 9.27). In contrast, PIK3CA mutation conferred no significant effect on mortality among patients with KRAS-mutated tumors (HR = 1.25; 95% CI, 0.52 to 2.96). CONCLUSION: Among patients who undergo a curative resection of colon cancer, PIK3CA mutation is associated with shorter cancer-specific survival. The adverse effect of PIK3CA mutation may be potentially limited to patients with KRAS wild-type tumors.