Associations between the Gut Microbiota, Race, and Ethnicity of Patients with Colorectal Cancer: A Pilot and Feasibility Study

BACKGROUND

Colorectal cancer (CRC) is more prevalent among some racial and ethnic minority and low socioeconomic status populations. Although the gut microbiota is a risk factor for CRC and varies with race and ethnicity, its role in CRC disparities remains poorly understood.

METHODS

We examined the feasibility of recruiting sociodemographically diverse CRC patients for a microbiome study involving a home stool collection. We also explored whether race and ethnicity were associated with gut microbiome composition. We recruited Black/African American, Hispanic/Latino, and non-Hispanic White patients who were receiving care for active CRC to complete a comprehensive dietary and lifestyle survey, self-collect a stool sample, and complete an exit interview. Gut microbial diversity and composition were analyzed using 16S rRNA gene sequencing.

RESULTS

30 individuals consented (of 35 who were eligible and contacted) with 5 (17%) Black/African American, 11 (37%) Hispanic/Latino, and 14 (46%) non-Hispanic White. A total of 22 (73%) completed the dietary and lifestyle survey; 18 (63%) returned a stool sample. Even after controlling for socioeconomic, dietary, or treatment-related covariates, microbiome composition was associated with race and ethnicity. Fusobacteriota (a phylum associated with the development and progression of CRC) was significantly higher in the Black/African American group compared to others, and microbial diversity was higher in samples from non-Hispanic White individuals compared to Hispanic/Latino individuals.

CONCLUSION

Our study shows that it is feasible to recruit and collect stool samples from diverse individuals with CRC and found significant associations in gut microbial structure with race and ethnicity.

Variety of Fruit and Vegetables and Alcohol Intake are Associated with Gut Microbial Species and Gene Abundance in Colorectal Cancer Survivors

BACKGROUND

Adherence to the American Cancer Society (ACS) guidelines of avoiding obesity, maintaining physical activity, and consuming a diet rich in fruits, vegetables, and whole grains is associated with longer survival in colorectal cancer (CRC) survivors. Dietary components of the ACS guidelines may act in part by changing the microbiome, which is implicated in CRC outcomes.

OBJECTIVES

We conducted a pilot cross-sectional study to explore associations between ACS guidelines and the gut microbiome.

METHODS

Stool samples and questionnaires were collected from 28 CRC survivors at the University of California, San Francisco from 2019 to 2020. ACS scores were calculated based on validated questionnaires. Gut microbial community structure from 16S amplicons and gene/pathway abundances from metagenomics were tested for associations with the ACS score and its components using ANOVA and general linear models.

RESULTS

The overall ACS score was not significantly associated with variations in the fecal microbiota. However, fruit and vegetable intake and alcohol intake accounted for 19% (P = 0.005) and 13% (P = 0.01) of variation in the microbiota, respectively. Fruit/vegetable consumption was associated with increased microbial diversity, increased Firmicutes, decreased Bacteroidota, and changes to multiple genes and metabolic pathways, including enriched pathways for amino acid and short-chain fatty acid biosynthesis and plant-associated sugar degradation. In contrast, alcohol consumption was positively associated with overall microbial diversity, negatively associated with Bacteroidota abundance, and associated with changes to multiple genes and metabolic pathways. The other components of the ACS score were not statistically significantly associated with the fecal microbiota in our sample.

CONCLUSIONS

These results guide future studies examining the impact of changes in the intake of fruits, vegetables, and alcoholic drinks on the gut microbiome of CRC survivors.

Sexual function remains persistently low in women after treatment for colorectal cancer and anal squamous cell carcinoma

BACKGROUND

Women diagnosed with colorectal cancer (CRC) or anal squamous cell carcinoma (ASCC) are at high risk of sexual dysfunction after treatment, yet little is known about recovery and risk factors for chronic dysfunction.

AIM

We aimed to describe sexual function and sexual activity among women who underwent definitive treatment for CRC or ASCC, examine relationships between time since treatment completion and sexual function, and explore factors associated with desire and changes in sexual desire over time.

METHODS

As part of a prospective cohort study of patients with gastrointestinal cancer at the University of California San Francisco, female-identifying participants who finished definitive treatment for CRC or ASCC completed the Female Sexual Function Index (FSFI) at 6- to 12-month intervals. We used multivariable linear mixed models to explore factors associated with the FSFI desire subscale.

OUTCOMES

Outcomes were rates of sexual activity, proportion at risk for sexual dysfunction (FSFI score <26.55), total FSFI score, and FSFI desire subscale.

RESULTS

Among the 97 cancer survivors who completed at least 1 FSFI, the median age was 59 years, the median time since treatment end was 14 months, and 87% were menopausal. Fifty-five women (57%) had a history of colon cancer; 21 (22%), rectal cancer; and 21 (22%), ASCC. An additional 13 (13%) had a current ostomy. Approximately half the women were sexually active (n = 48, 49%). Among these 48 sexually active women, 34 (71%) had FSFI scores indicating risk for sexual dysfunction. Among the 10 sexually active women who completed a FSFI ≥2 years since end of treatment, the median total score was 22.6 (IQR, 15.6-27.3). None of the evaluated characteristics were associated with desire (age, tumor site, treatment, menopause status, or ostomy status).

CLINICAL IMPLICATIONS

Consistent with prior studies, we found low desire scores after treatment for CRC or ASCC, with little recovery over time, suggesting that patients should not expect an eventual rebound of sexual function.

STRENGTHS AND LIMITATIONS

Strengths of our study include longitudinal data and use of the validated FSFI. Women with ASCC composed 22% of our cohort, allowing for insight into this rare disease group. Limitations of this study include the small sample size, particularly for longitudinal analyses, and the enrollment of patients at variable times since treatment end.

CONCLUSION

We observed a high prevalence of sexual health concerns, including low desire, after the treatment of CRC and ASCC that persisted for years after treatment was completed.

Quality of life among colorectal cancer survivors participating in a pilot randomized controlled trial of a web-based dietary intervention with text messages

PURPOSE

We aimed to estimate the effect of a 12-week web-based dietary intervention with text messages on quality of life (QoL) among colorectal cancer (CRC) survivors.

METHODS

Between 2017 and 2018, 50 CRC survivors were randomized (1:1) to receive a 12-week web-based dietary intervention with daily text messages or wait-list control. Health-related QoL was assessed using the European Organization for the Research and Treatment of Cancer (EORTC) Quality of Life Questionnaire-Core 30 (QLQ-C30) and colorectal quality of life module (QLQ-CR29) at baseline, 12, and 24 weeks. Within- and between-group mean changes in health-related QoL with 95% confidence intervals (CI) were calculated for both arms.

RESULTS

Compared to the controls, participants receiving the intervention had an improvement in emotional functioning (mean change: 14.3; 95% CI: 3.0, 25.6) at 12 weeks and social functioning (mean change: 13.8; 95% CI: 2.1, 25.5) at 24 weeks. A decrease of fatigue from baseline was also observed in the intervention arm (mean change: - 9.1; 95% CI: - 17.1, - 1.1) at 24 weeks. No other changes in QoL scores were associated with the intervention.

CONCLUSION

CRC survivors randomized to receive a web-based dietary intervention with text messages experienced higher emotional and social functioning. Further study with a larger population may be warranted.

TRIAL REGISTRATION

clinicaltrials.gov, NCT02965521. Registered 16 November 2016, https://clinicaltrials.gov/ct2/keydates/NCT02965521.

A reversible SRC-relayed COX2 inflammatory program drives resistance to BRAF and EGFR inhibition in BRAFV600E colorectal tumors

BRAF^V600E mutation confers a poor prognosis in metastatic colorectal cancer (CRC) despite combinatorial targeted therapies based on the latest understanding of signaling circuitry. To identify parallel resistance mechanisms induced by BRAF-MEK-EGFR co-targeting, we used a high-throughput kinase activity mapping platform. Here we show that SRC kinases are systematically activated in BRAF^V600E CRC following targeted inhibition of BRAF ± EGFR and that coordinated targeting of SRC with BRAF ± EGFR increases treatment efficacy in vitro and in vivo. SRC drives resistance to BRAF ± EGFR targeted therapy independently of ERK signaling by inducing transcriptional reprogramming through β-catenin (CTNNB1). The EGFR-independent compensatory activation of SRC kinases is mediated by an autocrine prostaglandin E₂ loop that can be blocked with cyclooxygenase-2 (COX2) inhibitors. Co-targeting of COX2 with BRAF + EGFR promotes durable suppression of tumor growth in patient-derived tumor xenograft models. COX2 inhibition represents a drug-repurposing strategy to overcome therapeutic resistance in BRAF^V600E CRC.

Phase I prospective trial of TAS-102 (trifluridine and tipiracil) and radioembolization with 90Y resin microspheres for chemo-refractory colorectal liver metastases

BACKGROUND

Extrahepatic disease progression limits clinical efficacy of Yttrium-90 (⁹⁰Y) radioembolization (TARE) for patients with chemotherapy-refractory metastatic colorectal cancer (mCRC). Trifluridine and tipiracil (TAS-102) has overall survival benefit for patients with refractory mCRC and may be a radiosensitizer.

METHODS

Sequential lobar TARE using ⁹⁰Y resin microspheres in combination with TAS-102 in 28-day cycles were used to treat adult patients with bilobar liver-dominant chemo-refractory mCRC according to 3 + 3 dose escalation design with a 12-patient dose expansion cohort. Study objectives were to establish safety and determine maximum tolerated dose (MTD) of TAS-102 in combination with TARE.

RESULTS

A total of 21 patients (14 women, 7 men) with median age of 60 years were enrolled. No dose limiting toxicities were observed. Treatment related severe adverse events included cytopenias (10 patients, 48%) and radioembolization-induced liver disease (2 patients, 10%). Disease control rate in the liver lobes treated with TARE was 100%. Best observed radiographic responses were partial response for 4 patients (19%) and stable disease for 12 patients (57%).

CONCLUSIONS

The combination of TAS-102 and TARE for patients with liver-dominant mCRC is safe and consistently achieves disease control within the liver.

TRIAL REGISTRATION

ClinicalTrials.gov identifier NCT02602327 (first posted 11/11/2015).

Abstract B011: Network propagation of the kinase activity signatures of therapy-resistant tumors reveals novel druggable targets in BRAF(V600E)-mutated colorectal cancer

Despite combination therapies targeting BRAF and EGFR, metastatic colorectal cancer (mCRC) with a BRAF(V600E) mutation confers poor prognosis with early development of drug resistance in a majority of patients. Treatment with a current standard of care (encorafenib plus panitumumab) temporarily suppresses tumor growth, but fails to promote regression and leads to eventual disease progression. Consequently, there is a need to better characterize the compensatory resistance pathways that are activated in response to treatment. To identify these parallel resistance mechanisms and novel druggable targets, we analyzed the effects of combination treatment with encorafenib (a BRAF-inhibitor) and panitumumab (an anti-EGFR antibody) in BRAF(V600E) mCRC patient-derived xenograft (PDX) tumor samples via a high throughput kinase activity mapping (HT-KAM) platform and advanced computational tools. HT-KAM uses libraries of peptides as combinatorial sensors that identify and measure the activity of &gt;160 kinases involved in oncogenic pathways (Coppé et al 2019). As these key kinases provide an informative yet filtered view of proteome-wide signaling effects, we developed a network-based workflow to further analyze our HT-KAM results. Network propagation methods were applied to integrate this data into ReactomeFI, a well-validated gene/protein interaction network. Significant genes from the network propagation results were clustered and enriched for pathway analysis using additional scripts, and results were visualized using Cytoscape. Based on HT-KAM results comparing the kinase signatures of PDX tumors treated with encorafenib + panitumumab versus vehicle, EGFR was confirmed to be downregulated. Moreover, several kinases previously identified as (re-)activated upon treatment and progression were significantly upregulated, including kinases in the RAF–MEK–ERK cascade as well as AKTs and downstream effectors. In addition, STK11, a tumor suppressor also known as LKB1, was significantly downregulated, while the activity of several kinases involved in cell surface signaling were upregulated, including PKA and PKCs. Network propagation of this data and enrichment of network subclusters resulted in a broad range of pathways implicated in persistent cell survival. Among top hits, signaling networks orchestrated by GPCRs, MTOR, WNT and beta-catenin were significantly enriched, suggesting that multiple interacting pathways coordinate the response and resistance to BRAF/EGFR joint inhibition. Our workflow implementing network propagation and enrichment analysis of HT-KAM data pinpoints essential pathways that contain druggable targets. We are in the process of validating these dependencies in PDX models and translating these mechanisms into novel combinatorial targeted therapy interventions designed to overcome drug resistance in BRAF(V600E) mCRC.

Citation Format: Yeonjoo Hwang, Mehdi Bouhaddou, Christina Moelders, Denise P. Muñoz, Chloe E. Atreya, Jean-Philippe Coppé. Network propagation of the kinase activity signatures of therapy-resistant tumors reveals novel druggable targets in BRAF(V600E)-mutated colorectal cancer [abstract]. In: Proceedings of the AACR Special Conference on Colorectal Cancer; 2022 Oct 1-4; Portland, OR. Philadelphia (PA): AACR; Cancer Res 2022;82(23 Suppl_1):Abstract nr B011.

Abstract IA020: The gut microbiome in colorectal cancer

The gut microbiome plays important roles in colorectal cancer (CRC) initiation, treatment, and survivorship. This talk will highlight preliminary results from two pilot studies: Gut microbiome & Oral fluoropyrimidines (GO) and Lifestyle and Outcome in Gastrointestinal Cancer (LOGIC). GO investigated the impact of oral fluoropyrimidines (e.g., capecitabine) on gut microbes via longitudinal stool sampling. Despite marked inter- and intra-individual differences in diversity and community structure, we detected multiple consistent taxonomic differences. LOGIC asked: how do diet and lifestyle, measured by the American Cancer Society (ACS) score, correlate with gut microbiota characteristics in CRC survivors? We found that components of the ACS score related to fruit and vegetable consumption, but not the overall ACS score, significantly associated with variations in microbial community structures, diversity, and differences in abundance of microorganisms at various taxonomic levels. Practical considerations influencing the design of follow-up studies in progress will be discussed.

Citation Format: Chloe E. Atreya. The gut microbiome in colorectal cancer [abstract]. In: Proceedings of the AACR Special Conference on Colorectal Cancer; 2022 Oct 1-4; Portland, OR. Philadelphia (PA): AACR; Cancer Res 2022;82(23 Suppl_1):Abstract nr IA020.

Optimizing intervention tools to improve nutrition and physical activity for colorectal cancer survivors (Tools To Be Fit): Study protocol of a randomized factorial experiment

BACKGROUND

Colorectal cancer (CRC) is the 2nd leading cause of cancer death in the United States. The American Cancer Society (ACS) Nutrition and Physical Activity Guidelines are associated with longer survival among CRC survivors, but few report behaviors consistent with the guidelines.

METHODS

The Tools To Be Fit study, based on the Multiphase Optimization Strategy (MOST) framework, is a full factorial experimental to optimize a remotely delivered 48-week diet and physical activity intervention for non-metastatic CRC survivors. The intervention includes a core component (booklet and personal report). CRC survivors (N = 400) are additionally randomly assigned to one of 16 combinations of four candidate components, each with 2 options: 1) text messaging (on/off); 2) self-monitoring modality (digital/paper); 3) health coaching (on/off); and 4) support person coaching (on/off).

OUTCOMES

Our primary outcome is adherence to the ACS guidelines after 48 weeks using a score that includes physical activity from accelerometers, dietary intake from a food frequency questionnaire, and body mass index (BMI) measured by a technician. Secondary outcomes include the ACS score after 24 weeks and score components at 24 and 48 weeks. Exploratory outcomes include adherence and change in Social Cognitive Theory constructs. We will explore moderation by sociodemographic, clinical, and psychological/behavioral factors; and change in the ACS score in relation to change in levels of insulin, insulin sensitivity, inflammation, gut microbiome structure, fatigue, depression, and sleep disturbance.

DISCUSSION

The proposed study aims to inform a randomized controlled trial to determine whether an optimized intervention reduces risk of recurrence among CRC survivors.

Association between adherence to the American Cancer Society Nutrition and Physical Activity Guidelines and stool frequency among colon cancer survivors: a cohort study

Purpose

We sought to determine whether adherence to the American Cancer Society (ACS) Nutrition and Physical Activity Guidelines was associated with better bowel function among colon cancer survivors.

Methods

This prospective cohort study included patients surgically treated for stage I–IV colon cancer enrolled in the Lifestyle and Outcomes after Gastrointestinal Cancer (LOGIC) study between February 2017 and May 2021. Participants were assigned an ACS score (0–6 points) at enrollment. Stool frequency (SF) was assessed every 6 months using the EORTC QLQ-CR29. Higher SF is an indication of bowel function impairment. ACS score at enrollment was examined in relation to SF at enrollment and over a 3-year period. Secondarily, we examined associations between the ACS score components (body mass index, dietary factors, and physical activity) and SF. Multivariable models were adjusted for demographic and surgical characteristics.

Results

A total of 112 people with colon cancer (59% women, mean age 59.5 years) were included. Cross-sectionally, for every point increase in ACS score at enrollment, the odds of having frequent stools at enrollment decreased by 43% (CI 0.42–0.79; p < 0.01). Findings were similar when we examined SF as an ordinal variable and change in SF over a 3-year period. Lower consumption of red/processed meats and consuming a higher number of unique fruits and vegetables were associated with lower SF (better bowel function) at enrollment.

Conclusions

Colon cancer survivors who more closely followed the ACS nutrition and physical activity guidelines had lower SF, an indication of better bowel function.

Implications for Cancer Survivors

Our findings highlight the value of interventions that support health behavior modification as part of survivorship care for long-term colon cancer survivors.

Host and gut bacteria share metabolic pathways for anti-cancer drug metabolism

Pharmaceuticals have extensive reciprocal interactions with the microbiome, but whether bacterial drug sensitivity and metabolism is driven by pathways conserved in host cells remains unclear. Here we show that anti-cancer fluoropyrimidine drugs inhibit the growth of gut bacterial strains from 6 phyla. In both Escherichia coli and mammalian cells, fluoropyrimidines disrupt pyrimidine metabolism. Proteobacteria and Firmicutes metabolized 5-fluorouracil to its inactive metabolite dihydrofluorouracil, mimicking the major host mechanism for drug clearance. The preTA operon was necessary and sufficient for 5-fluorouracil inactivation by E. coli, exhibited high catalytic efficiency for the reductive reaction, decreased the bioavailability and efficacy of oral fluoropyrimidine treatment in mice and was prevalent in the gut microbiomes of colorectal cancer patients. The conservation of both the targets and enzymes for metabolism of therapeutics across domains highlights the need to distinguish the relative contributions of human and microbial cells to drug efficacy and side-effect profiles.

mHealth Interventions to Promote a Healthy Diet and Physical Activity among Cancer Survivors: A Systematic Review of Randomized Controlled Trials

Simple Summary

The number of cancer survivors has increased dramatically in the past several decades. Research indicates that health behaviors, including having a healthy diet and engaging in regular exercise, may improve the treatment outcomes and quality of life of cancer survivors. Behavioral interventions using web and mobile technology may be feasible and acceptable approaches to modify physical activity and dietary behaviors. This review summarizes the feasibility, acceptability and estimated effects of physical activity and dietary interventions using web and mobile technology from the published studies.

Abstract

Background: Technology-based interventions are increasingly used to improve physical activity (PA) and diet. Methods: We conducted a systematic review of randomized controlled trials (RCTs) published up to August 2021 that tested mobile health (mHealth) PA and/or dietary interventions among cancer survivors and reported on the feasibility, satisfaction, behavioral change, and/or quality of life (QOL) outcomes. Results: In total, 61 articles were identified on PubMed, and 23 of those met the inclusion criteria. The most common cancers were breast (n = 1000), prostate (n = 713), and colorectal (n = 650). Participants were predominantly White (median: 84%, interquartile range (IQR): 20%) and college-educated (58%). The interventions varied, but the most common combination of components (six studies) was a website/mobile app with an activity tracker and coaching. In terms of duration, 70% (n = 16) of the interventions lasted 12 weeks. The median total tracker wear was 87% of the study days (IQR: 6%) and the median text-message reply rate was 73% (IQR 4%). Most participants (median: 87%; IQR: 16%) were satisfied with at least one intervention component. Eleven out of 18 studies examining behavioral change reported significant between-group differences and six out of 11 studies examining QoL reported significant improvements. Conclusions: mHealth interventions are a promising approach to improving the PA and diets of cancer survivors. Research in racially/ethnically and socioeconomically diverse populations is needed.

Being Present 2.0: Online Mindfulness-Based Program for Metastatic Gastrointestinal Cancer Patients and Caregivers

Purpose

A metastatic cancer diagnosis is associated with high levels of distress in patients and caregivers, which may be alleviated by mindfulness interventions. Research on scalable, tailored, online mindfulness training programs is needed. We sought to test the feasibility and acceptability of a remotely delivered 8-week mindfulness-based intervention, Being Present 2.0 (BP2.0).

Methods

We performed a single-arm feasibility study of BP2.0 among patients with any metastatic gastrointestinal cancer receiving chemotherapy, with or without an informal caregiver. Participants were instructed to practice mindfulness using pre-recorded guided meditations 5 times per week using a study-specific website and to attend a weekly live, interactive virtual meeting facilitated by a trained instructor. The web-based platform enabled direct measurement of adherence.

Results

The study enrolled 46 of 74 (62%) patients contacted, together with 23 caregivers (69 participants total), from May to October 2018. Median patient age was 52 (range 20-70 years), 39% were male, 67% non-Hispanic white, 65% had colorectal cancer, and 78% lived outside of San Francisco. The top reasons cited for participation were to reduce stress/anxiety and learn how to meditate. Mean baseline National Comprehensive Cancer Network Distress Thermometer (NCCN DT) scores were 4.7 (patients) and 5.8 (caregivers). The study discontinuation rate was 20% (eight patients and six caregivers). Among the remaining 55 participants, 43 (78%) listened to at least one audio recording and/or attended at least one virtual meeting, although adherence data was incomplete. The retention rate was 71%, with 39 participants completing at least one follow-up assessment. In post-intervention qualitative interviews, 88% of respondents reported a positive experience. Compared to baseline, participants reported significantly reduced post-intervention NCCN DT scores (mean 3.1; P = .012).

Conclusion

The BP2.0 online mindfulness-based program is feasible and acceptable for patients with metastatic gastrointestinal cancer and caregivers. These results will guide plans for a follow-up efficacy study. ClinicalTrials.gov Identifier: NCT03528863.

Feasibility and Acceptability of a Physical Activity Tracker and Text Messages to Promote Physical Activity During Chemotherapy for Colorectal Cancer: Pilot Randomized Controlled Trial (Smart Pace II)

Background

We conducted a pilot 2-arm randomized controlled trial to assess the feasibility of a digital health intervention to increase moderate-to-vigorous physical activity in patients with colorectal cancer (CRC) during chemotherapy.

Objective

This study aimed to determine whether a digital health physical activity intervention is feasible and acceptable during chemotherapy for CRC.

Methods

Potentially eligible patients with CRC expected to receive at least 12 weeks of chemotherapy were identified in person at the University of California, San Francisco, and on the web through advertising. Eligible patients were randomized 1:1 to a 12-week intervention (Fitbit Flex, automated SMS text messages) versus usual care. At 0 and 12 weeks, patients wore an Actigraph GT3X+ accelerometer for 7 days and completed surveys, body size measurements, and an optional 6-minute walk test. Participants could not be masked to their intervention arm, but people assessing the body size and 6-minute walk test outcomes were masked. The primary outcomes were adherence (eg, Fitbit wear and text response rate) and self-assessed acceptability of the intervention. The intervention would be considered feasible if we observed at least 80% complete follow-up and 70% adherence and satisfaction, a priori.

Results

From 2018 to 2020, we screened 240 patients; 53.3% (128/240) of patients were ineligible and 26.7% (64/240) declined to participate. A total of 44 patients (44/240, 18%) were randomized to the intervention (n=22) or control (n=22) groups. Of these, 57% (25/44) were women; 68% (30/44) identified as White and 25% (11/44) identified as Asian American or Pacific Islander; and 77% (34/44) had a 4-year college degree. The median age at enrollment was 54 years (IQR 45-62 years). Follow-up at 12 weeks was 91% (40/44) complete. In the intervention arm, patients wore Fitbit devices on a median of 67 out of 84 (80%) study days and responded to a median of 17 out of 27 (63%) questions sent via SMS text message. Among 19 out of 22 (86%) intervention patients who completed the feedback survey, 89% (17/19) were satisfied with the Fitbit device; 63% (12/19) were satisfied with the SMS text messages; 68% (13/19) said the SMS text messages motivated them to exercise; 74% (14/19) said the frequency of SMS text messages (1-3 days) was ideal; and 79% (15/19) said that receiving SMS text messages in the morning and evening was ideal.

Conclusions

This pilot study demonstrated that many people receiving chemotherapy for CRC are interested in participating in digital health physical activity interventions. Fitbit adherence was high; however, participants indicated a desire for more tailored SMS text message content. Studies with more socioeconomically diverse patients with CRC are required.

Trial Registration

ClinicalTrials.gov NCT03524716; https://clinicaltrials.gov/ct2/show/NCT03524716

Discovering dominant tumor immune archetypes in a pan-cancer census

Cancers display significant heterogeneity with respect to tissue of origin, driver mutations, and other features of the surrounding tissue. It is likely that individual tumors engage common patterns of the immune system-here "archetypes"-creating prototypical non-destructive tumor immune microenvironments (TMEs) and modulating tumor-targeting. To discover the dominant immune system archetypes, the University of California, San Francisco (UCSF) Immunoprofiler Initiative (IPI) processed 364 individual tumors across 12 cancer types using standardized protocols. Computational clustering of flow cytometry and transcriptomic data obtained from cell sub-compartments uncovered dominant patterns of immune composition across cancers. These archetypes were profound insofar as they also differentiated tumors based upon unique immune and tumor gene-expression patterns. They also partitioned well-established classifications of tumor biology. The IPI resource provides a template for understanding cancer immunity as a collection of dominant patterns of immune organization and provides a rational path forward to learn how to modulate these to improve therapy.

Characteristics and Growth Rate of Lung Metastases in Patients With Primary Gastrointestinal Malignancies and Lung-dominant Metastatic Disease: A Retrospective Cohort Analysis

INTRODUCTION

There are no formal guidelines for the management of patients with primary gastrointestinal (GI) cancers who have lung-exclusive or lung-predominant metastases. We performed a retrospective analysis to evaluate host and tumor characteristics of this patient population, model patterns and rates of growth, and describe treatment approaches.

MATERIALS AND METHODS

Eligible patients had a GI cancer with either synchronous or metachronous lung metastases but no other visceral or peritoneal sites of involvement. In addition to collecting detailed patient-specific and tumor-specific information, all imaging studies (computed tomography±positron emission tomography scans) were reviewed by an independent radiologist. Up to 5 lung metastases were tracked through each patient's clinical course. Growth rate was estimated using a linear mixed model analysis.

RESULTS

Forty patients met eligibility criteria (18 pancreatic, 15 colorectal, 6 hepatobiliary, 1 gastroesophageal; synchronous vs. metachronous, 13 and 27, respectively). Median time from original cancer diagnosis to onset of metachronous lung lesions was 16 months. Interval from first appearance of lung metastases to treatment initiation was 6.2 months. Average growth rate of the largest lesion was 0.21 mm/mo (95% confidence interval, 0.12-0.30), with substantial intrapatient and interpatient variability. Sixty percent of patients underwent locoregional interventions in addition to or in lieu of systemic therapy for their lung metastases. Median survival of the entire study cohort from first appearance of lung metastases was 54 months.

CONCLUSIONS

Lung metastases from primary GI cancers have a variable but overall indolent natural history and are generally associated with prolonged survival outcomes. Further efforts to define patterns of growth of lung metastases, informed by size, number, and clinical/molecular features, are needed to guide appropriate timing and selection of therapy as well as surveillance strategies.

Molecular and Radiological Features of Microsatellite Stable Colorectal Cancer Cases With Dramatic Responses to Immunotherapy

BACKGROUND/AIM

The majority of colorectal cancer (CRC) cases, which are microsatellite stable (MSS) and do not harbor mismatch repair deficiency/microsatellite instability, are resistant to immunotherapy. Identification of patients with exceptional responses in MSS CRC and predictive biomarkers is an unmet need that needs to be addressed.

CASE REPORT

We report three cases of MSS CRC with durable clinical benefit from immunotherapy with anti-PD-1 checkpoint inhibitors. Two cases bear a POLE P286R mutation, which has been associated with lack of immunotherapy response in MSS CRC. Two cases bear alterations in Ataxia-Telangiectasia Mutated (ATM) which may contribute to observed responses, including interaction with a co-administered intratumoral stimulator of interferon genes (STING) pathway agonist in one patient.

CONCLUSION

Novel DNA damage repair alterations, including mutations in ATM, can provide insight into additional mechanisms by which genomic alterations can sensitize MSS CRC to diverse immunotherapies.

Randomized Trial of Irinotecan and Cetuximab With or Without Vemurafenib in BRAF-Mutant Metastatic Colorectal Cancer (SWOG S1406)

PURPOSE

BRAFV600E mutations are rarely associated with objective responses to the BRAF inhibitor vemurafenib in patients with metastatic colorectal cancer (CRC). Blockade of BRAFV600E by vemurafenib causes feedback upregulation of EGFR, whose signaling activities can be impeded by cetuximab.

METHODS

One hundred six patients with BRAFV600E-mutated metastatic CRC previously treated with one or two regimens were randomly assigned to irinotecan and cetuximab with or without vemurafenib (960 mg PO twice daily).

RESULTS

Progression-free survival, the primary end point, was improved with the addition of vemurafenib (hazard ratio, 0.50, P = .001). The response rate was 17% versus 4% (P = .05), with a disease control rate of 65% versus 21% (P < .001). A decline in circulating tumor DNA BRAFV600E variant allele frequency was seen in 87% versus 0% of patients (P < .001), with a low incidence of acquired RAS alterations at the time of progression. RNA profiling suggested that treatment benefit did not depend on previously established BRAF subgroups or the consensus molecular subtype.

CONCLUSION

Simultaneous inhibition of EGFR and BRAF combined with irinotecan is effective in BRAFV600E-mutated CRC.

Molecular Insights in Transmission of Cancer From an Organ Donor to Four Transplant Recipients

Organ donors are systematically screened for infection, whereas screening for malignancy is less rigorous. The true incidence of donor-transmitted malignancies is unknown due to a lack of universal tumor testing in the posttransplant setting. Donor-transmitted malignancy may occur even when not suspected based on donor or recipient factors, including age and time to cancer diagnosis. We describe the detection of a gastrointestinal adenocarcinoma transmitted from a young donor to 4 transplant recipients. Multidimensional histopathologic and genomic profiling showed a CDH1 mutation and MET amplification, consistent with gastric origin. At the time of writing, one patient in this series remains alive and without evidence of cancer after prompt organ explant after cancer was reported in other recipients. Because identification of a donor-derived malignancy changes management, our recommendation is to routinely perform short tandem repeat testing (or a comparable assay) immediately upon diagnosis of cancer in any organ transplant recipient. Routine testing for a donor-origin cancer and centralized reporting of outcomes are necessary to establish a robust evidence base for the future development of clinical practice guidelines.

Factors Impacting Differential Outcomes in the Definitive Radiation Treatment of Anal Cancer Between HIV-Positive and HIV-Negative Patients

BACKGROUND

Anal squamous cell carcinoma (ASCC) is uncommon, yet seen more frequently in the setting of the human immunodeficiency virus (HIV). Chemoradiotherapy is the definitive modality of treatment for patients with ASCC; this study examines factors impacting clinical outcomes in a large cohort of HIV-positive and HIV-negative patients.

METHODS

A retrospective review was conducted of patients treated for nonmetastatic ASCC at a single institution between 2005 and 2018. Freedom from local recurrence (FFLR), freedom from distant metastasis, and overall survival (OS) were calculated using the Kaplan-Meier method, and univariate and multivariate analysis were performed using the Cox proportional hazards model.

RESULTS

During the study period, 111 patients initiated definitive treatment for ASCC. Median age of the entire cohort was 56.7 years (interquartile range, 51.5-63.5), with 52 patients (46.8%) being HIV-positive. At median follow-up of 28.0 months, the 2- and 5-year FFLR were 78.2% (95% confidence interval [CI], 70.4-87.0) and 74.6% (95% CI, 65.8-84.5), respectively. Multivariate analysis revealed time from diagnosis to treatment initiation (median, 8 weeks; hazard ratio, 1.06; 95% CI, 1.03-1.10) to be significantly associated with worse FFLR and OS. HIV-positive patients had a trend toward worse FFLR (log-ranked p = .06). For HIV-positive patients with post-treatment CD4 less than 150 cells per mm3 , there was significantly worse OS (log-ranked p = .015).

CONCLUSION

A trend toward worse FFLR was seen in HIV-positive patients, despite similar baseline disease characteristics as HIV-negative patients. Worse FFLR and OS was significantly associated with increased time from diagnosis to treatment initiation. Poorer OS was seen in HIV-positive patients with a post-treatment CD4 count less than 150 cells per mm3 .

IMPLICATIONS FOR PRACTICE

Human immunodeficiency virus (HIV)-positive patients with anal squamous cell carcinoma can represent a difficult clinical scenario. Definitive radiation with concurrent chemotherapy is highly effective but can result in significant toxicity and a decrease in CD4 count that could predispose to HIV-related complications. As HIV-positive patients have largely been excluded from prospective clinical trials, this study seeks to provide greater understanding of their outcomes with radiation therapy, potential predictors of worse local control and overall survival, and those most at risk after completion of treatment.

BRAF-Mutant Transcriptional Subtypes Predict Outcome of Combined BRAF, MEK, and EGFR Blockade with Dabrafenib, Trametinib, and Panitumumab in Patients with Colorectal Cancer

PURPOSE

The influence of the transcriptional and immunologic context of mutations on therapeutic outcomes with targeted therapy in cancer has not been well defined. BRAF V600E-mutant (BM) colorectal cancer comprises two main transcriptional subtypes, BM1 and BM2. We sought to determine the impact of BM subtype, as well as distinct biological features of those subtypes, on response to BRAF/MEK/EGFR inhibition in patients with colorectal cancer.

PATIENTS AND METHODS

Paired fresh tumor biopsies were acquired at baseline and on day 15 of treatment from all consenting patients with BM colorectal cancer enrolled in a phase II clinical trial of dabrafenib, trametinib, and panitumumab. For each sample, BM subtype, cell cycle, and immune gene signature expression were determined using RNA-sequencing (RNA-seq), and a Cox proportional hazards model was applied to determine association with progression-free survival (PFS).

RESULTS

Confirmed response rates, median PFS, and median overall survival (OS) were higher in BM1 subtype patients compared with BM2 subtype patients. Evaluation of immune contexture identified greater immune reactivity in BM1, whereas cell-cycle signatures were more highly expressed in BM2. A multivariate model of PFS incorporating BM subtype plus immune and cell-cycle signatures revealed that BM subtype encompasses the majority of the effect.

CONCLUSIONS

BM subtype is significantly associated with the outcome of combination dabrafenib, trametinib, and panitumumab therapy and may serve as a standalone predictive biomarker beyond mutational status. Our findings support a more nuanced approach to targeted therapeutic decisions that incorporates assessment of transcriptional context.

Embedded palliative care for patients with metastatic colorectal cancer: a mixed-methods pilot study

PURPOSE

Palliative care is recommended for patients with metastatic cancer, but there has been limited research about embedded palliative care for specific patient populations. We describe the impact of a pilot program that provided routine, early, integrated palliative care to patients with metastatic colorectal cancer.

METHODS

Mixed methods pre-post intervention cohort study at an academic cancer center. Thirty control then 30 intervention patients with metastatic colorectal cancer were surveyed at baseline and 1, 3, 6, 9, and 12 months thereafter about symptoms, quality-of-life, and likelihood of cure. We compared survey responses, trends over time, rates of advance care planning, and healthcare utilization between groups. Patients, family caregivers, and clinicians were interviewed.

RESULTS

Patients in the intervention group were followed for an average of 6.5 months and had an average of 3.5 palliative care visits. At baseline, symptoms were mild (average 1.85/10) and 78.2% of patients reported good/excellent quality-of-life. Half (50.9%) believed they were likely to be cured of cancer. Over time, symptoms and quality-of-life metrics remained similar between groups, however intervention patients were more realistic about their likelihood of cure (p = 0.008). Intervention patients were more likely to have a surrogate documented (83.3% vs. 26.7%, p < 0.0001), an advance directive completed (63.3% vs. 13.3%, p < 0.0001), and non-full code status (43.3% vs. 16.7%, p < 0.03). All patients and family caregivers would recommend the program to others with cancer.

CONCLUSIONS

We describe the impact of an embedded palliative care program for patients with metastatic colorectal cancer, which improved prognostic awareness and rates of advance care planning.

Postoperative Exacerbation of Oxaliplatin-induced Neurotoxicity in Gastrointestinal Cancers: A Case Series

BACKGROUND/AIM

Oxaliplatin-induced neurotoxicity (OIN) can be severe and dose-limiting with clinically significant symptoms that persist for years. Few published reports have described postoperative exacerbation of OIN and more longitudinal data are needed to better characterize the phenomenon.

PATIENTS AND METHODS

We identified 13 patients diagnosed with colon (n=7), rectal (n=4) or pancreatic (n=2) cancer who experienced postoperative OIN exacerbation at our medical center. Charts were reviewed for demographic and clinical data regarding OIN.

RESULTS

OIN exacerbation was documented 0.5-7.0 months after the first surgery following oxaliplatin exposure, with a median duration of 10.6 months (range=1.4-86.1 months). OIN exacerbation persisted in 3/13 patients at last follow-up, and improved to pre-operative levels in 6/13 patients (with complete resolution in 4/13) within a median of 3.6 months from initial exacerbation.

CONCLUSION

Given the widespread use of oxaliplatin in neoadjuvant and first-line treatment for gastrointestinal cancers, further study is warranted to prospectively and systematically define risks for postoperative OIN exacerbation.

Clinicopathologic Characteristics and Impact of Oophorectomy for Ovarian Metastases from Colorectal Cancer

BACKGROUND

As survival with metastatic colorectal cancer (CRC) and imaging modalities improve, detection of ovarian metastases may be increasing. The ovary may serve as a sanctuary site for malignant cells; however, there is a paucity of data regarding the role for oophorectomy.

METHODS

This is a single-institution retrospective study of patients with CRC with ovarian metastases from 2009 to 2017. We evaluated patient, disease, and treatment related factors associated with overall survival (OS) from initial diagnosis of metastatic CRC.

RESULTS

Of 108 patients assessed, the median age was 50, 19% had localized disease at initial presentation, 64% had ovarian metastases at initial CRC diagnosis, and 77% underwent oophorectomy. Median OS was 29.6 months across all patients, and it was 36.7 months in patients who underwent oophorectomy versus 25.0 months in patients who did not (hazard ratio [HR] 0.54). In multivariate analysis, the effect of oophorectomy on OS suggested protection but was not statistically significant (HR 0.57). Resection of primary tumor was performed in 71% of patients, which was independently associated with improved OS (HR 0.21). Twelve patients (11%) remained alive at 5 years after diagnosis of metastatic disease.

CONCLUSION

Although it has been previously reported that patients with CRC with ovarian metastases have poor prognosis, the median OS for this cohort was comparable to existing OS data for patients with metastatic CRC. In patients treated with chemotherapy, we did not find the ovarian metastasis to frequently serve as a sanctuary site of disease. However, we found that in carefully selected patients, oophorectomy may confer a survival benefit.

IMPLICATIONS FOR PRACTICE

In colorectal cancer (CRC) ovarian metastasis is not necessarily associated with worse prognosis than metastasis to other sites. In carefully selected patients with ovarian metastases from CRC, oophorectomy may confer a survival benefit. Specifically, development of ovarian metastasis early in the disease course, resection of the primary tumor, and limited extraovarian metastatic disease are clinical features that are potentially associated with benefit from oophorectomy. A subset of patients with ovarian metastasis from CRC have potential to become long-term survivors (>5 years).

Feasibility and Acceptability of a Web-Based Dietary Intervention with Text Messages for Colorectal Cancer: A Randomized Pilot Trial

BACKGROUND

Diet is associated with colorectal cancer survival. Yet, adherence to nutrition guidelines is low among colorectal cancer survivors.

METHODS

We conducted a pilot trial among colorectal cancer survivors to evaluate a 12-week remote dietary intervention. Participants received print materials and were randomized (1:1) to intervention (website, text messages) or wait-list control. Primary outcomes included feasibility and acceptability. We also explored change in diet from 0 to 12 and 24 weeks and change from 0 to 12 weeks in anthropometry and circulating biomarkers (Trial Registration: NCT02965521).

RESULTS

We randomized 50 colorectal cancer survivors (25 intervention, 25 control). Retention was 90% at 12 weeks and 84% at 24 weeks. Participants had a median age of 55 years and were 66% female, 70% non-Hispanic white, and 96% had a college degree. The intervention arm responded to a median 15 (71%) of 21 text messages that asked for a reply [interquartile range (IQR) = 8, 19] and visited the website a median of 13 (15%) days (IQR = 1, 33) of the 84 study days.

CONCLUSIONS

We developed a Web-based dietary intervention for colorectal cancer survivors. Our pilot results suggest that colorectal cancer survivors may engage more with text messages than a study website. Research to improve tailoring of text messages, while maintaining scalability, is needed.

IMPACT

Remote dietary interventions using text messages may be feasible for colorectal cancer survivors.See all articles in this CEBP Focus section, "Modernizing Population Science."

Abstract B023: A reversible SRC-relayed COX2-inflammatory program drives therapeutic resistance in BRAF(V600E) colorectal tumors

Metastatic colorectal cancer (mCRC) harboring a BRAF(V600E) mutation is associated with poor prognosis and limited treatment options. Clinical trials targeting BRAF with MEK ± EGFR in 2- and 3-drug combinatorial therapy regimens have produced modest response rates and progression-free survival, with early development of resistance in most patients. Considerable efforts to study the mutational landscape or gene expression profiles or synthetic lethal genetic interactions of BRAF(V600E) mCRC have remained relatively ineffective at pinpointing novel therapeutic susceptibilities. This suggests that intrinsic resistance of BRAF(V600E) mCRC to combinatorial treatments is not driven by individual genetic dependencies, but is rather mediated by the concerted upregulation of multiple, parallel signaling pathways that cooperate to circumvent therapeutic effectiveness. To characterize which signaling circuits are rewired by BRAF and EGFR-targeted therapy, we used our new high throughput kinase activity mapping (HT-KAM) platform (Coppé et al 2019 Nature Cell Biology), which can reveal druggable kinase dependencies in cancer cell lines and tumor biospecimens by directly measuring the phospho-catalytic activity of kinases using their biological peptide targets as phospho-sensors. Out of the concerted, reprogrammed kinase circuits we identified with HT-KAM, we found a highly conserved, cell-autonomous, SRC kinases-relayed, COX2-PGE2-GNAS-driven inflammatory program that functions independently of the commonly studied BRAF-MEK-ERK / EGFR / PDPK1-AKT1 pathways. Specifically, we found that SRC family kinases are catalytically activated upon single and combination treatment with BRAF ± MEK ± EGFR inhibitors. We validated the specificity and potency of this BRAF/EGFR-independent vulnerability using genetic interventions (via shRNA or CRISPR) and drug treatments (adding dasatinib or saracatinib) in cell survival and colony formation assays across &gt;15 BRAF(V600E) cell lines, and in patient tumor-derived xenograft (PDX) mouse models. Immunohistochemistry performed on patient tumors resistant to targeted therapies, and on residual PDX tumors after BRAF and MEK treatments, further reiterated SRC activation. Mechanistically, the activation of SRC kinases was induced by an autocrine PGE2-regulated GNAS-activation loop that COX2-inhibitors celecoxib or valdecoxib reversed both in vitro and in vivo. In PDX models, addition of celecoxib significantly improved tumor growth inhibition, and systematically outperformed 2- and 3-drug targeted therapy regimens tested in clinical trials without increasing toxicity (manuscript in preparation). In conclusion, we demonstrate that SRC-signaling is at the nexus of an autonomous inflammatory program with pro-tumorigenic activities, which may explain why BRAF(V600E) colorectal tumors develop resistance to current therapies. Moreover, targeting COX2 presents a promising new clinical strategy to restore therapeutic sensitivity in patients.

Citation Format: Chloe E Atreya, Ana Ruiz-Saenz, Changjun Wang, Bo Pan, Courtney A Dreyer, Diede Brunen, Anirudh Prahallad, Danislav Spassov, Dana J Steffen, Byron C Hann, Scott R VandenBerg, Silvio Gutkind, Mark M Moasser, Laura J van 't Veer, Jean-Philippe Coppe. A reversible SRC-relayed COX2-inflammatory program drives therapeutic resistance in BRAF(V600E) colorectal tumors [abstract]. In: Proceedings of the AACR-NCI-EORTC International Conference on Molecular Targets and Cancer Therapeutics; 2019 Oct 26-30; Boston, MA. Philadelphia (PA): AACR; Mol Cancer Ther 2019;18(12 Suppl):Abstract nr B023. doi:10.1158/1535-7163.TARG-19-B023

Phase II Open-Label Study of Pembrolizumab in Treatment-Refractory, Microsatellite Instability-High/Mismatch Repair-Deficient Metastatic Colorectal Cancer: KEYNOTE-164

PURPOSE

KEYNOTE-164 (NCT02460198) evaluated the antitumor activity of pembrolizumab in previously treated, metastatic, microsatellite instability–high/mismatch repair–deficient (MSI-H/dMMR) colorectal cancer (CRC).

METHODS

This phase II open-label study involved 128 centers worldwide. Eligible patients were age ≥ 18 years and had metastatic MSI-H/dMMR CRC treated with ≥ 2 prior lines of standard therapy, including fluoropyrimidine, oxaliplatin, and irinotecan with or without anti–vascular endothelial growth factor/epidermal growth factor receptor monoclonal antibody (cohort A) or ≥ 1 prior line of therapy (cohort B). MSI-H/dMMR status was assessed locally. Patients received pembrolizumab 200 mg every 3 weeks for up to 2 years until progression, unacceptable toxicity, or withdrawal. The primary end point was objective response rate by RECIST version 1.1 by independent central review. Secondary end points were duration of response, progression-free survival (PFS), overall survival, safety, and tolerability.

RESULTS

A total of 124 patients with MSI-H/dMMR CRC (61 in cohort A, 63 in cohort B) enrolled. At data cutoff, median follow-up was 31.3 months (range, 0.2-35.6 months) for cohort A and 24.2 months (range, 0.1-27.1 months) for cohort B. Objective response rate was 33% (95% CI, 21% to 46%) and 33% (95% CI, 22% to 46%), respectively, with median duration of response not reached in either cohort. Median PFS was 2.3 months (95% CI, 2.1 to 8.1 months) and 4.1 months (95% CI, 2.1 to 18.9 months). Median overall survival was 31.4 months (95% CI, 21.4 months to not reached) and not reached (95% CI, 19.2 months to not reached). Treatment-related grade 3-4 adverse events occurred in 10 patients (16%) in cohort A and 8 (13%) in cohort B, with the most common occurring in ≥ 2 patients being pancreatitis, fatigue, increased alanine aminotransferase, and increased lipase (2 patients each; 3%) in cohort A.

CONCLUSION

Pembrolizumab is effective with a manageable safety profile in patients with MSI-H/dMMR CRC.

A multi-modal data resource for investigating topographic heterogeneity in patient-derived xenograft tumors

Patient-derived xenografts (PDXs) are an essential pre-clinical resource for investigating tumor biology. However, cellular heterogeneity within and across PDX tumors can strongly impact the interpretation of PDX studies. Here, we generated a multi-modal, large-scale dataset to investigate PDX heterogeneity in metastatic colorectal cancer (CRC) across tumor models, spatial scales and genomic, transcriptomic, proteomic and imaging assay modalities. To showcase this dataset, we present analysis to assess sources of PDX variation, including anatomical orientation within the implanted tumor, mouse contribution, and differences between replicate PDX tumors. A unique aspect of our dataset is deep characterization of intra-tumor heterogeneity via immunofluorescence imaging, which enables investigation of variation across multiple spatial scales, from subcellular to whole tumor levels. Our study provides a benchmark data resource to investigate PDX models of metastatic CRC and serves as a template for future, quantitative investigations of spatial heterogeneity within and across PDX tumor models.

Hormone receptor expression of colorectal cancer diagnosed during the peri-partum period

BACKGROUND

Colorectal carcinoma (CRC) during the peri-partum period is challenging to diagnose due to the overlapping symptoms of CRC and pregnancy. This is the first case series to investigate clinicopathologic, hormonal and molecular features of CRC diagnosed during the peri-partum period. We hypothesized that advanced presentations of CRC could possibly be mitigated by pregnancy-related hormonal factors.

METHODS

We conducted a retrospective review of five women diagnosed with CRC during the peri-partum period and studied the clinical and molecular features of their cancer.

RESULTS

All patients presented with stage IV CRC at diagnosis; three had primary tumors in the rectum and two had primary tumors in the sigmoid colon. The liver was the most common metastatic site (three of five women). Immunohistochemistry stains were negative for estrogen receptors alpha (ERα) and beta (ERβ), and one tumor demonstrated low-level positivity for PR (1%). Formalin-fixed and paraffin-embedded (FFPE) biopsies from each case were tested with next-generation sequencing and found that all tumors were mismatch repair (MMR) proficient, and three harbored a KRAS mutation. Germline testing showed no predisposition to CRC; however, several somatic variants of undetermined significance (VUS) were identified.

DISCUSSION

CRC in the peri-partum period poses significant risk factors for presentations with advanced disease due to diagnostic challenges. While our study provides no evidence that pathogenesis of CRC during pregnancy is driven by elevated estrogen and/or progesterone levels during pregnancy, additional putative etiologic factors, including placental growth factors, the immunosuppressive state of pregnancy and other physiologic processes during pregnancy, warrant future study.

Improving Access to Integrative Oncology Through Group Medical Visits: A Pilot Implementation Project

Objectives: This article describes the implementation of a group medical visit (GMV) model to increase access to integrative oncology (IO) care. The most challenging and critical time to access high-quality IO care is while patients are receiving conventional cancer therapy. Often demand for individual IO clinic consultations precludes this from occurring. A three-session GMV program was designed to alleviate barriers to receiving integrative care during active cancer treatment. Design: A consolidated framework was used for implementation research and focused ethnography methods to describe the IO GMV implementation process. Data sources included patient evaluations, participant observation, and brief provider and patient interviews. Setting: A pilot program was created to assess the feasibility and acceptability of implementing IO GMVs at a comprehensive cancer center. Intervention: Each three-session GMV consisted of a didactic session, followed by individual visits with the integrative oncologist. Results: The setting, intervention, and implementation process of the IO GMV program were described. Thirty-two patients participated in the first five cohorts of the program. Twenty-two were women; 24 were White. The median age of participants was 52. Patient evaluations demonstrate high levels of satisfaction with the program with all scored aspects rated >4.0 on a five-point Likert scale. For the medical center, group visits are a financially viable alternative to individual IO visits; revenue from group visits exceeded the revenue potential of 6 h of individual visits by an average of 38%. Conclusion: GMVs are a feasible and promising model for increasing access to IO. Patients in active cancer treatment were able to participate in the program. Future research and implementation efforts could examine health outcomes over time after participation in GMVs, as well as the feasibility of using this model with more diverse patient populations.

Of Microbes and Microsatellites

A ubiquitous oral cavity microbe, Fusobacterium nucleatum, is increasingly being implicated in colorectal cancer pathogenesis. An article in this issue elucidates the differential association of F. nucleatum with tumor-infiltrating lymphocytes depending on microsatellite instability status. Cancer Immunol Res; 6(11); 1290-1. ©2018 AACR See article by Hamada et al., p. 1327.

Self-monitoring and reminder text messages to increase physical activity in colorectal cancer survivors (Smart Pace): a pilot randomized controlled trial

Background

Over 1.3 million people live with colorectal cancer in the United States. Physical activity is associated with lower risk of colorectal cancer recurrence and mortality. Interventions are needed to increase physical activity in colorectal cancer survivors.

Methods

We conducted a 2-arm non-blinded pilot randomized controlled trial at the University of California, San Francisco among 42 individuals who had completed curative-intent treatment for colorectal cancer to determine the feasibility and acceptability of a 12-week (84 days) physical activity intervention using a Fitbit Flex™ and daily text messages. Participants were randomized 1:1 to receive the intervention with print educational materials or print educational materials alone. We explored the impact of the intervention versus usual care on physical activity using ActiGraph GT3X+ accelerometers pre−/post-intervention.

Results

We screened 406 individuals and randomized 42 to intervention (n = 21) or control (n = 21) groups. During the 12-week study, the intervention arm wore their Fitbits a median of 74 days [88% of days in study period, interquartile range: 23–83 days] and responded to a median of 34 (out of 46) text messages that asked for a reply (interquartile range: 13–38 text messages). Among the 16 intervention participants who completed the feedback survey, the majority (88%) reported that the intervention motivated them to exercise and that they were satisfied with their experience. No statistically significant difference in change in moderate-to-vigorous physical activity was found from baseline to 12 weeks between arms.

Conclusion

A 12-week physical activity intervention with a Fitbit and text messages was feasible and acceptable among colorectal cancer patients after curative treatment. Larger studies are needed to determine whether the intervention increases physical activity.

Trial registration

Clinicaltrials.gov Identifier NCT02966054. Registered 17 November 2016, retrospectively registered.

Electronic supplementary material

The online version of this article (10.1186/s12885-019-5427-5) contains supplementary material, which is available to authorized users.

Being Present: A single-arm feasibility study of audio-based mindfulness meditation for colorectal cancer patients and caregivers

A metastatic cancer diagnosis is associated with high levels of distress in patients and caregivers. Mindfulness interventions can reduce distress and improve quality of life in cancer patients. However, standard mindfulness training relies on in-person instruction, which is often not practical for either patients receiving chemotherapy or their caregivers. In the Being Present single arm pilot study, we designed and tested an 8-week audio-based mindfulness meditation program for patients with metastatic colorectal cancer receiving chemotherapy with or without a participating caregiver. The study accrued 33 of 74 (45%) eligible patients consenting together with 20 family caregivers (53 participants total) within nine months. Forty-one participants were evaluable (77%); 10 of 12 cases of attrition were attributable to hospitalization or death. Median participant age was 51 (range 21-78 years); 38% were men. Baseline levels of distress were similar in patients and caregivers. The top reasons for participation cited in pre-intervention interviews were to increase relaxation/calm, improve mood/emotions, and reduce stress/anxiety. In measures of adherence, 59% of responses to weekly texts asking: "Have you practiced today?" were "Yes" and 59% of interviewees reported practicing >50% of the time. Compared to baseline, post-intervention surveys demonstrated significantly reduced distress (p = 0.01) and anxiety (p = 0.03); as well as increased non-reactivity (p<0.01), and feeling at peace (p<0.01). Post-intervention qualitative interviews, where 71% of participants reported benefit, were consistent with quantitative findings. In the interviews, participants spontaneously described reduced stress/anxiety and increased relaxation/calm. Benefits appeared to be accentuated in patient-caregiver pairs as compared to unpaired patients. Seventy-nine percent of participants reported plans for continued practice after study completion. We conclude that the Being Present audio-based mindfulness meditation program is of interest to, feasible, and acceptable for patients with metastatic colorectal cancer and caregivers, with initial evidence of efficacy. These results will guide plans for a follow-up study.

TRIAL REGISTRATION

ClinicalTrials.gov NCT02423720.

Combined BRAF, EGFR, and MEK Inhibition in Patients with BRAFV600E-Mutant Colorectal Cancer

Although BRAF inhibitor monotherapy yields response rates >50% in BRAFV600-mutant melanoma, only approximately 5% of patients with BRAFV600E colorectal cancer respond. Preclinical studies suggest that the lack of efficacy in BRAFV600E colorectal cancer is due to adaptive feedback reactivation of MAPK signaling, often mediated by EGFR. This clinical trial evaluated BRAF and EGFR inhibition with dabrafenib (D) + panitumumab (P) ± MEK inhibition with trametinib (T) to achieve greater MAPK suppression and improved efficacy in 142 patients with BRAFV600E colorectal cancer. Confirmed response rates for D+P, D+T+P, and T+P were 10%, 21%, and 0%, respectively. Pharmacodynamic analysis of paired pretreatment and on-treatment biopsies found that efficacy of D+T+P correlated with increased MAPK suppression. Serial cell-free DNA analysis revealed additional correlates of response and emergence of KRAS and NRAS mutations on disease progression. Thus, targeting adaptive feedback pathways in BRAFV600E colorectal cancer can improve efficacy, but MAPK reactivation remains an important primary and acquired resistance mechanism.Significance: This trial demonstrates that combined BRAF + EGFR + MEK inhibition is tolerable, with promising activity in patients with BRAFV600E colorectal cancer. Our findings highlight the MAPK pathway as a critical target in BRAFV600E colorectal cancer and the need to optimize strategies inhibiting this pathway to overcome both primary and acquired resistance. Cancer Discov; 8(4); 428-43. ©2018 AACR.See related commentary by Janku, p. 389See related article by Hazar-Rethinam et al., p. 417This article is highlighted in the In This Issue feature, p. 371.

Emerging treatment options for BRAF-mutant colorectal cancer

The personalization of cancer care is rooted in the premise that there are subsets of patients with tumors harboring clinically relevant targets for patient-specific treatments. Colorectal cancer (CRC) is a disease that has historically been notable for its dearth of biomarkers that are predictive of response to targeted therapies. In recent years, BRAFV600E-mutated CRC has emerged as a distinct biologic entity, typically refractory to standard chemotherapy regimens approved for the treatment of metastatic CRC and associated with a dismal prognosis. Multiple clinical trials sought to replicate the successes of targeted therapies seen in BRAFV600E-mutated melanoma without success; metastatic BRAFV600E-mutated CRC is clearly a distinct biologic entity. We review a number of recent studies demonstrating the evidence of modest responses to combinations of BRAF, EGFR, and/or MEK inhibition in patients with metastatic BRAFV600E-mutated CRC; however, despite advances, overall survival remains far inferior for these patients compared to their BRAF-wild-type counterparts. Development of combination therapies to impede signaling through the MAPK pathway through alternate targets remains an area of active investigation. Reflecting the rapid evolution of efforts for this small subset of CRC patients, the first-ever Phase III study is now underway evaluating the combination of BRAF, EGFR, and MEK inhibition. Immunotherapies are also an area of active research, particularly for the subset of patients with tumors that are also microsatellite instability (MSI) high. Here, we summarize the current landscape and emerging data on the molecular, clinical, and therapeutic aspects of BRAF-mutant CRC.

Genomic Landscape of Cell-Free DNA in Patients with Colorectal Cancer

"Liquid biopsy" approaches analyzing cell-free DNA (cfDNA) from the blood of patients with cancer are increasingly utilized in clinical practice. However, it is not yet known whether cfDNA sequencing from large cohorts of patients with cancer can detect genomic alterations at frequencies similar to those observed by direct tumor sequencing, and whether this approach can generate novel insights. Here, we report next-generation sequencing data from cfDNA of 1,397 patients with colorectal cancer. Overall, frequencies of genomic alterations detected in cfDNA were comparable to those observed in three independent tissue-based colorectal cancer sequencing compendia. Our analysis also identified a novel cluster of extracellular domain (ECD) mutations in EGFR, mediating resistance by blocking binding of anti-EGFR antibodies. Patients with EGFR ECD mutations displayed striking tumor heterogeneity, with 91% harboring multiple distinct resistance alterations (range, 1-13; median, 4). These results suggest that cfDNA profiling can effectively define the genomic landscape of cancer and yield important biological insights.Significance: This study provides one of the first examples of how large-scale genomic profiling of cfDNA from patients with colorectal cancer can detect genomic alterations at frequencies comparable to those observed by direct tumor sequencing. Sequencing of cfDNA also generated insights into tumor heterogeneity and therapeutic resistance and identified novel EGFR ectodomain mutations. Cancer Discov; 8(2); 164-73. ©2017 AACR.This article is highlighted in the In This Issue feature, p. 127.

Systemic Therapy for Metastatic Colorectal Cancer: From Current Standards to Future Molecular Targeted Approaches

Over the past 20 years, substantial advances have been made in the treatment of patients with metastatic colorectal cancer (mCRC). In particular, there is now a wide range of options for the front-line treatment of mCRC. Sophisticated molecular technologies have been developed to identify novel prognostic and predictive biomarkers for CRC. DNA sequencing technology has made remarkable advances in recent years, primarily as a result of the development of next-generation sequencing and whole exome sequencing, which are powerful new tools for the discovery of predictive molecular biomarkers to facilitate the delivery of personalized medicine. In addition to tumor tissue, recent efforts have focused on analyzing circulating tumor DNA in peripheral blood. Herein, we review the evolution of standard chemotherapy and targeted therapy strategies for the treatment of mCRC in the front-line setting, the molecular technologies that are presently being used to facilitate our ability to practice individualized medicine, and the practical aspects of applying molecular biomarkers to everyday clinical practice.

Radioembolization with 90Y glass microspheres for the treatment of unresectable metastatic liver disease from chemotherapy-refractory gastrointestinal cancers: final report of a prospective pilot study

BACKGROUND

This prospective pilot single-institution study was undertaken to document the feasibility, safety, and efficacy of radioembolization of liver-dominant metastatic gastrointestinal cancer using ⁹⁰Y glass microspheres.

METHODS

Between June 2010 and October 2013, 42 adult patients (26 men, 16 women; median age 60 years) with metastatic chemotherapy-refractory unresectable colorectal (n=21), neuroendocrine (n=11), intrahepatic bile duct (n=7), pancreas (n=2), and esophageal (n=1) carcinomas underwent 60 lobar or segmental administrations of ⁹⁰Y glass microspheres. Data regarding clinical and laboratory adverse events (AE) were collected prospectively for up to 5.5 years after radioembolization. Radiographic responses were evaluated using Response Evaluation Criteria in Solid Tumors (RECIST), version 1.1. Time to maximum response, response duration, progression-free survival (PFS) (hepatic and extrahepatic), and overall survival (OS) were measured.

RESULTS

Median target dose and activity were 109.4 Gy and 2.6 GBq per treatment session, respectively. Majority of clinical AE were grade 1 or 2 in severity. Patients with colorectal cancer had hepatic objective response rate (ORR) of 25% and a hepatic disease control rate (DCR) of 80%. Median PFS and OS were 1.0 and 4.4 months, respectively. Patients with neuroendocrine tumors (NET) had hepatic ORR and DCR of 73% and 100%, respectively. Median PFS was 8.9 months for this cohort. DCR and median PFS and OS for patients with cholangiocarcinoma were 86%, 1.1 months, and 6.7 months, respectively.

CONCLUSIONS

⁹⁰Y glass microspheres device has a favorable safety profile, and achieved prolonged disease control of hepatic tumor burden in a subset of patients, including all patients enrolled in the neuroendocrine cohort.

Differential Radiographic Appearance of BRAF V600E-Mutant Metastatic Colorectal Cancer in Patients Matched by Primary Tumor Location

BACKGROUND

BRAF-mutant metastatic colorectal cancers (mCRCs) share many clinicopathologic features with right-sided colon tumors, including frequent peritoneal involvement. Because of the poorer outcomes associated with BRAF mutations, early enrollment in clinical trials has been encouraged. However, the use of standard eligibility and assessment criteria, such as measurable disease, has anecdotally impeded patient accrual and restricted appraisal of treatment response. We investigated whether the presence of a BRAF V600E mutation is differentially associated with sites and appearance of metastatic disease in patients matched by primary tumor location.

METHODS

A total of 40 patients with BRAF-mutant mCRC were matched to 80 patients with BRAF wild-type mCRC by location of primary tumor (right or left colon; rectum), sex, and age. Associations between BRAF mutation status and clinicopathologic characteristics and metastatic sites were analyzed using proportion tests. Survival was summarized with Kaplan-Meier and Cox regression methods.

RESULTS

The distribution of primary tumor locations was: 60% right colon, 30% left colon, and 10% rectum. Compared with BRAF wild-type tumors, BRAF-mutant tumors more commonly associated with peritoneal metastases (50% vs 31%; P=.045) and ascites (50% vs 24%; P=.0038). In patients with left colon primaries, BRAF mutations were associated with more frequent ascites (58% vs 12%; P=.0038) and less frequent liver metastases (42% vs 79%; P=.024). Among patients with right colon primaries, no significant difference in sites of disease by BRAF mutation status was observed. Disease was not measurable by RECIST 1.1 in 24% of patients with right-sided primary tumors, irrespective of BRAF mutation status. In the BRAF-mutated cohort, ascites correlated unfavorably with survival (hazard ratio, 2.35; 95% CI, 1.14, 4.83; P=.02).

CONCLUSIONS

Greater frequency of ascites and peritoneal metastases, which pose challenges for RECIST 1.1 interpretation of therapeutic outcomes, are seen with BRAF-mutant mCRC, even when patients are matched for primary tumor location.

A phase II study of axitinib in advanced neuroendocrine tumors

Neuroendocrine tumors (NETs) are highly vascular neoplasms overexpressing vascular endothelial growth factor (VEGF) as well as VEGF receptors (VEGFR). Axitinib is a potent, selective inhibitor of VEGFR-1, -2 and -3, currently approved for the treatment of advanced renal cell carcinoma. We performed an open-label, two-stage design, phase II trial of axitinib 5mg twice daily in patients with progressive unresectable/metastatic low-to-intermediate grade carcinoid tumors. The primary end points were progression-free survival (PFS) and 12-month PFS rate. The secondary end points included time to treatment failure (TTF), overall survival (OS), overall radiographic response rate (ORR), biochemical response rate and safety. A total of 30 patients were enrolled and assessable for toxicity; 22 patients were assessable for response. After a median follow-up of 29months, we observed a median PFS of 26.7months (95% CI, 11.4-35.1), with a 12-month PFS rate of 74.5% (±10.2). The median OS was 45.3 months (95% CI, 24.4-45.3), and the median TTF was 9.6months (95% CI, 5.5-12). The best radiographic response was partial response (PR) in 1/30 (3%) and stable disease (SD) in 21/30 patients (70%); 8/30 patients (27%) were unevaluable due to early withdrawal due to toxicity. Hypertension was the most common toxicity that developed in 27 patients (90%). Grade 3/4 hypertension was recorded in 19 patients (63%), leading to treatment discontinuation in six patients (20%). Although axitinib appears to have an inhibitory effect on tumor growth in patients with advanced, progressive carcinoid tumors, the high rate of grade 3/4 hypertension may represent a potential impediment to its use in unselected patients.

Combined BRAF and MEK Inhibition With Dabrafenib and Trametinib in BRAF V600-Mutant Colorectal Cancer

PURPOSE

To evaluate dabrafenib, a selective BRAF inhibitor, combined with trametinib, a selective MEK inhibitor, in patients with BRAF V600-mutant metastatic colorectal cancer (mCRC).

PATIENTS AND METHODS

A total of 43 patients with BRAF V600-mutant mCRC were treated with dabrafenib (150 mg twice daily) plus trametinib (2 mg daily), 17 of whom were enrolled onto a pharmacodynamic cohort undergoing mandatory biopsies before and during treatment. Archival tissues were analyzed for microsatellite instability, PTEN status, and 487-gene sequencing. Patient-derived xenografts were established from core biopsy samples.

RESULTS

Of 43 patients, five (12%) achieved a partial response or better, including one (2%) complete response, with duration of response > 36 months; 24 patients (56%) achieved stable disease as best confirmed response. Ten patients (23%) remained in the study > 6 months. All nine evaluable during-treatment biopsies had reduced levels of phosphorylated ERK relative to pretreatment biopsies (average decrease ± standard deviation, 47% ± 24%). Mutational analysis revealed that the patient achieving a complete response and two of three evaluable patients achieving a partial response had PIK3CA mutations. Neither PTEN loss nor microsatellite instability correlated with efficacy. Responses to dabrafenib plus trametinib were comparable in patient-derived xenograft-bearing mice and the biopsied lesions from each corresponding patient.

CONCLUSION

The combination of dabrafenib plus trametinib has activity in a subset of patients with BRAF V600-mutant mCRC. Mitogen-activated protein kinase signaling was inhibited in all patients evaluated, but to a lesser degree than observed in BRAF-mutant melanoma with dabrafenib alone. PIK3CA mutations were identified in responding patients and thus do not preclude response to this regimen. Additional studies targeting the mitogen-activated protein kinase pathway in this disease are warranted.

Cell-Free DNA Next-Generation Sequencing in Pancreatobiliary Carcinomas

Patients with pancreatic and biliary carcinomas lack personalized treatment options, in part because biopsies are often inadequate for molecular characterization. Cell-free DNA (cfDNA) sequencing may enable a precision oncology approach in this setting. We attempted to prospectively analyze 54 genes in tumor and cfDNA for 26 patients. Tumor sequencing failed in 9 patients (35%). In the remaining 17, 90.3% (95% confidence interval, 73.1%-97.5%) of mutations detected in tumor biopsies were also detected in cfDNA. The diagnostic accuracy of cfDNA sequencing was 97.7%, with 92.3% average sensitivity and 100% specificity across five informative genes. Changes in cfDNA correlated well with tumor marker dynamics in serial sampling (r = 0.93). We demonstrate that cfDNA sequencing is feasible, accurate, and sensitive in identifying tumor-derived mutations without prior knowledge of tumor genotype or the abundance of circulating tumor DNA. cfDNA sequencing should be considered in pancreatobiliary cancer trials where tissue sampling is unsafe, infeasible, or otherwise unsuccessful.

SIGNIFICANCE

Precision medicine efforts in biliary and pancreatic cancers have been frustrated by difficulties in obtaining adequate tumor tissue for next-generation sequencing. cfDNA sequencing reliably and accurately detects tumor-derived mutations, paving the way for precision oncology approaches in these deadly diseases.

Cell-Free DNA Next-Generation Sequencing in Pancreatobiliary Carcinomas

Patients with pancreatic and biliary carcinomas lack personalized treatment options, in part because biopsies are often inadequate for molecular characterization. Cell-free DNA (cfDNA) sequencing may enable a precision oncology approach in this setting. We attempted to prospectively analyze 54 genes in tumor and cfDNA for 26 patients. Tumor sequencing failed in 9 patients (35%). In the remaining 17, 90.3% (95% confidence interval, 73.1%-97.5%) of mutations detected in tumor biopsies were also detected in cfDNA. The diagnostic accuracy of cfDNA sequencing was 97.7%, with 92.3% average sensitivity and 100% specificity across five informative genes. Changes in cfDNA correlated well with tumor marker dynamics in serial sampling (r = 0.93). We demonstrate that cfDNA sequencing is feasible, accurate, and sensitive in identifying tumor-derived mutations without prior knowledge of tumor genotype or the abundance of circulating tumor DNA. cfDNA sequencing should be considered in pancreatobiliary cancer trials where tissue sampling is unsafe, infeasible, or otherwise unsuccessful.

SIGNIFICANCE

Precision medicine efforts in biliary and pancreatic cancers have been frustrated by difficulties in obtaining adequate tumor tissue for next-generation sequencing. cfDNA sequencing reliably and accurately detects tumor-derived mutations, paving the way for precision oncology approaches in these deadly diseases.

Potent antitumor activity of cabozantinib, a c-MET and VEGFR2 inhibitor, in a colorectal cancer patient-derived tumor explant model

Antiangiogenic therapy is commonly used for the treatment of colorectal cancer (CRC). Although patients derive some clinical benefit, treatment resistance inevitably occurs. The MET signaling pathway has been proposed to be a major contributor of resistance to antiangiogenic therapy. MET is upregulated in response to vascular endothelial growth factor pathway inhibition and plays an essential role in tumorigenesis and progression of tumors. In this study, we set out to determine the efficacy of cabozantinib in a preclinical CRC patient-derived tumor xenograft model. We demonstrate potent inhibitory effects on tumor growth in 80% of tumors treated. The greatest antitumor effects were observed in tumors that possess a mutation in the PIK3CA gene. The underlying antitumor mechanisms of cabozantinib consisted of inhibition of angiogenesis and Akt activation and significantly decreased expression of genes involved in the PI3K pathway. These findings support further evaluation of cabozantinib in patients with CRC. PIK3CA mutation as a predictive biomarker of sensitivity is intriguing and warrants further elucidation. A clinical trial of cabozantinib in refractory metastatic CRC is being activated.

Association of TP53 mutational status and gender with survival after adjuvant treatment for stage III colon cancer: results of CALGB 89803

PURPOSE

The TP53 tumor suppressor is frequently mutated in colon cancer, but the influence of such mutations on survival remains controversial. We investigated whether mutations in the DNA-binding domain of TP53 are associated with survival in stage III colon cancer.

EXPERIMENTAL DESIGN

The impact of TP53 genotype was prospectively evaluated in Cancer and Leukemia Group B 89803, a trial that randomized stage III colon cancer patients to receive adjuvant 5-fluorouracil/leucovorin (5FU/LV) or 5FU/LV with irinotecan (IFL).

RESULTS

TP53 mutations were identified in 274 of 607 cases. The presence of any TP53 mutation did not predict disease-free survival (DFS) or overall survival with either adjuvant regimen when men and women were considered together or as separate groups. However, outcome differences among women became apparent when tumor TP53 genotype was stratified as wild-type versus zinc- or non-zinc-binding mutations in the TP53 DNA-binding domain. DFS at 5 years was 0.59, 0.52, and 0.78 for women with TP53 wild-type tumors, and tumors with zinc- or non-zinc-binding mutations, respectively. Survival at 5 years for these same women was 0.72, 0.59, and 0.90, respectively. No differences in survival by TP53 genotype were observed in men.

CONCLUSIONS

The presence of any TP53 mutation within the DNA-binding domain did not predict survival in stage III colon cancer. However, TP53 genotype was predictive of survival in women following adjuvant therapy. Future colon cancer therapeutic trials, with inclusion of correlative molecular markers, should be designed to permit evaluation of survival and/or response to treatment in women separately from men.