Quantitative proteomic analysis of HER2 protein expression in PDAC tumors.

Metastatic pancreatic adenocarcinoma (PDAC) is the third leading cause of cancer-related death in the United States, with a 5-year survival rate of only 11%, necessitating identification of novel treatment paradigms. Tumor tissue specimens from patients with PDAC, breast cancer, and other solid tumor malignancies were collected and tumor cells were enriched using laser microdissection (LMD). Reverse phase protein array (RPPA) analysis was performed on enriched tumor cell lysates to quantify a 32-protein/phosphoprotein biomarker panel comprising known anticancer drug targets and/or cancer-related total and phosphorylated proteins, including HER2Total, HER2Y1248, and HER3Y1289. RPPA analysis revealed significant levels of HER2Total in PDAC patients at abundances comparable to HER2-positive (IHC 3+) and HER2-low (IHC 1+ /2+ , FISH-) breast cancer tissues, for which HER2 screening is routinely performed. These data support a critical unmet need for routine clinical evaluation of HER2 expression in PDAC patients and examination of the utility of HER2-directed antibody-drug conjugates in these patients.

Assessing Frailty in Gastrointestinal Cancer: Two Diseases in One?

PURPOSEOF REVIEW: This review examines the challenges of treating gastrointestinal cancer in the aging population, focusing on the importance of frailty assessment. Emphasized are the rise in gastrointestinal cancer incidence in older adults, advances in frailty assessments for patients with gastrointestinal cancer, the development of novel frailty markers, and a summary of recent trials. RECENT FINDINGS: Increasing evidence suggests that the use of a Comprehensive Geriatric Assessment (CGA) to identify frail older adults and individualize cancer care leads to lower toxicity and improved quality of life outcomes. However, the adoption of a full CGA prior to chemotherapy initiation in older cancer patients remains low. Recently, new frailty screening tools have emerged, including assessments designed to specifically predict chemotherapy-related adverse events. Additionally, frailty biomarkers have been developed, such as blood tests like IL-6 and performance tracking through physical activity monitors. The relevance of nutrition and muscle mass is discussed. Highlights from recent trials suggest the feasibility of successfully identifying patients most at risk of serious adverse events. There have been promising developments in identifying novel frailty markers and methods to screen for frailty in the older adult population. Further prospective trials that focus on and address the needs of the geriatric population for early identification of frailty in cancer care, facilitating a more tailored treatment approach. Practicing oncologists should select a frailty assessment to implement into their routine practice and adjust treatment accordingly.

Nivolumab Plus Ipilimumab in Patients With Solid Tumors With ATM Mutations: Results From the Targeted Agent and Profiling Utilization Registry (TAPUR) Study.

PURPOSE: The Targeted Agent and Profiling Utilization Registry Study is a phase II basket study evaluating the antitumor activity of commercially available targeted agents in patients with advanced cancers with genomic alterations known to be drug targets. Results of a cohort of patients with solid tumors with ATM mutations treated with nivolumab plus ipilimumab are reported. METHODS: Eligible patients had measurable disease (RECIST v.1.1), Eastern Cooperative Oncology Group performance status 0-2, adequate organ function, and no standard treatment options. Primary end point was disease control (DC), defined as complete (CR) or partial (PR) response or stable disease (SD) of at least 16 weeks duration (SD16+). Low-accruing histology-specific cohorts with ATM mutations treated with nivolumab plus ipilimumab were collapsed into a single histology-pooled cohort for this analysis. The results were evaluated based on a one-sided exact binomial test with a null DC rate of 15% versus 35% (power = .84; α = .10). Secondary end points were objective response (OR), progression-free survival, overall survival, duration of response, duration of SD, and safety. RESULTS: Twenty-nine patients with 10 tumor types with ATM mutations were enrolled from January 2018 to May 2020. One patient was not evaluable for efficacy. One CR, three PR, and three SD16+ were observed for DC and OR rates of 24% (P = .13; one-sided 90% CI: 14 to 100) and 14% (95% CI: 4 to 32), respectively. The null hypothesis of 15% DC rate was not rejected. Eleven patients had one treatment-related grade 3 adverse event (AE) or serious AE. There were two treatment-related patient deaths including immune-related encephalitis and respiratory failure. CONCLUSION: Nivolumab plus ipilimumab did not meet prespecified criteria to declare a signal of activity in patients with solid tumors with ATM mutations.

Molecular Pathogenesis of Cholangiocarcinoma: Implications for Disease Classification and Therapy.

Cholangiocarcinomas are an aggressive group of heterogeneous malignancies that affect over 210,000 individuals globally each year. Their incidence is rising, particularly in Western countries. Traditionally, cholangiocarcinomas are classified based on anatomic location of the tumor and are treated with similar cytotoxic chemotherapy despite significant molecular and genomic differences. With the rise of genetic and molecular sequencing, several driver mutations have been identified and targeted as novel therapeutic approaches. The most common genomic alterations include changes in FGFR2, IDH1, KRAS, BRAF, HER2, and the tumor suppressor p53. In addition, increased understanding of the cellular and molecular constituents of the tumor microenvironment (TME) has created opportunities for further novel therapeutic approaches. New strategies using combination therapies targeting driver mutations and various components of the TME hold promise for improved patient outcomes. This review covers the evolving molecular and therapeutic landscape of cholangiocarcinoma.

Concurrent BRAFV600E and BRCA Mutations in MSS Metastatic Colorectal Cancer: Prevalence and Case Series of mCRC patients with prolonged OS.

BACKGROUND: BRAF V600E+ microsatellite stable (MSS) metastatic colorectal cancer (mCRC) patients comprise up to 10% of advanced CRC. They have a poor prognosis with a median survival typically <1 year. Despite use of multi-agent 1st line chemotherapy regimens and combination targeted therapies, outcomes are still poor. In our Institutional Molecular Tumor Board (MTB) database, we identified 3 mCRC patients with MSS/BRAF V600E who also had a BRCA1 or BRCA2 co-mutation and had relatively long overall survivals. Prior studies suggested that BRCA mutations are uncommon in CRC and we queried the Foundation Medicine (FM) genomic database to evaluate the prevalence of these cases as well as those with co-mutations in other homologous recombination genes. METHODS: 36,966 CRC pts were sequenced by FMI using hybrid capture comprehensive genomic profiling (CGP) to evaluate all classes of genomic alterations (GA) for pathogenic BRAF mutations and/or a mutation in BRCA1/2 or a co-mutation in other homologous recombination (HR) genes (BARD1, CDK12, FANCL, PALB2, ATM, RAD54L, CHEK2, BRAF, BRIP1, RAD51D, RAD51C, RAD51B, CHEK1). Selected cohort analysis of BRAF V600E co-mutated with BRCA1 and BRCA2 were separated into MSI-H and MSS cohorts. The clinicopathological features and genomic loss of heterozygosity (gLOH) of those with a BRAF V600E and a BRCA1/BRCA2 mutation were collected and analyzed. We also describe 3 consecutive cases of mCRC patients, identified through the Inova Schar Cancer Institute (ISCI) MTB registry, whom had prolonged OS. RESULTS: Of 36,966 colorectal cancer pts, 6.6% were BRAF V600E+ and 1.5% had any co-occurring HR gene mutation(s) with 0.6% of the total mCRC population having co-ocurring BRAF V600E and BRCA1/2 alterations. BRCA co-mutations were higher in MSI-High BRAF V600E, however 24.1% of co-occurrences were observed in MSS samples. BRCA1 co-mutation was more commonly associated with MSS BRAF V600E and was associated with a higher gLOH than MSI-H BRAF V600E (18.7% vs 2.8%; p <0.001). In our institutional MTB database, (3/241;1.2%) CRC patients were MSS, BRAF V600E+ with BRCA1 or BRCA2 co-mutations, all somatic in origin, with an average gLOH of 21.4% and overall survivals of 72+(alive), 17+(alive), and 30 months, respectively. CONCLUSION: Co-existence of BRAF V600E/BRCA1/2 may represent a unique subset of advanced MSS CRC that may have a better prognosis and represent an opportunity to test novel targeted therapies. The elevated gLOH in these cases may also be a valuable biomarker for these pts. Larger prospective clinical validation trials in this subset is warranted.

Treatment Paradigms for Older Adults with Pancreatic Cancer: a Nuanced Approach.

OPINION STATEMENT: Pancreatic cancer is increasing in incidence in the USA. This disease disproportionately affects older adults, and as the percentage of adults > 65 years old increases with the aging of the baby boomers, the prevalence is expected to rise over the coming decade. These patients are often more susceptible to disease-related symptoms and have less ability to withstand both cancer and treatment-related side effects. Therefore, it is imperative that treating physicians thoughtfully consider their recommended treatment approach towards this vulnerable patient population. This review focuses on the current state of research of older adults with pancreatic adenocarcinoma, highlighting deficiencies in the representation of this patient population in clinical trials. It is vital that the treating physicians take a nuanced approach towards therapy of localized and metastatic disease in geriatric patients. A one size fits all treatment algorithm is no longer appropriate in any cancer patient, let alone the elders who are particularly vulnerable to developing treatment-related toxicities. To help guide therapy decisions, it is important to perform a comprehensive geriatric assessment which may uncover unexpected frailty and lead to a change in the recommended treatment approach. In this way, we can support older adults during therapy for this aggressive malignancy and provide optimal care.

Dosing Schedules of Gemcitabine and nab-Paclitaxel for Older Adults With Metastatic Pancreatic Cancer.

Background: Gemcitabine and nab-paclitaxel (GA) is a first-line treatment for patients with metastatic pancreatic cancer (mPDAC). The traditional dosing schedule of GA is days 1, 8, and 15 of a 28-day cycle. Frequently, older adults are given a modified dosing schedule using 2 doses per cycle because of toxicity. We retrospectively analyzed treatment patterns and outcomes of older adults with mPDAC given these 2 dosing schedules. Methods: Patients 65 years or older with mPDAC treated with GA in a nationwide real-world database between January 1, 2014, and May 31, 2019, were included. Demographic, disease, and treatment information were collected. Patients were grouped by dosing at treatment initiation (traditional vs modified dosing schedules). Endpoints were time on treatment (TOT) and overall survival (OS) in patients receiving at least 2 cycles. All statistical tests were 2-sided. Results: 1317 patients were included (traditional dosing schedule: n = 842; modified dosing schedule: n = 475). Median age at diagnosis was 72 and 73 years for traditional and modified dosing schedules, respectively (P < .001), but sex, race, and performance status were not statistically significantly different. The median TOT and OS were better for the traditional vs modified dosing schedule (unadjusted median TOT, first-line = 4.18 vs 3.26 mo, P =.04; OS = 9.44 vs 7.63 mo, P =.003). Conclusion: In this real-world cohort, treatment of older mPDAC patients with a modified dosing schedule of GA resulted in shorter TOT and worse OS vs a traditional dosing schedule. With the caveats of potential confounding that exist in a nonrandomized retrospective database, these results suggest that dose intensity may be important, and prospective studies are necessary to ensure we treat our patients most effectively.

Corrigendum: Clinical Utilization Pattern of Liquid Biopsies (LB) to Detect Actionable Driver Mutations, Guide Treatment Decisions and Monitor Disease Burden During Treatment of 33 Metastatic Colorectal Cancer (mCRC) Patients (pts) at a Fox Chase Cancer Center GI Oncology Subspecialty Clinic.

[This corrects the article DOI: 10.3389/fonc.2018.00652.].

First-in-Human Phase 1b Trial of Quinacrine Plus Capecitabine in Patients With Refractory Metastatic Colorectal Cancer.

BACKGROUND: Quinacrine plus a fluoropyrimidine has in vivo efficacy against metastatic colorectal cancer (mCRC). This phase 1b trial evaluated the combination of quinacrine plus capecitabine in patients with treatment-refractory mCRC. PATIENTS AND METHODS: Using a modified Simon accelerated titration design, adults with treatment-refractory mCRC were treated with capecitabine 1000 mg/m2 twice daily for 14/21-day cycle, and escalating doses of quinacrine 100 mg daily, 100 mg twice daily, and 200 mg twice daily for 21 days. The primary endpoint was identifying the maximum tolerated dose, determining tolerability and safety. In an expansion cohort, it was overall response rate and time to tumor progression (TTP). RESULTS: Ten patients (median age of 60 years) were treated in phase 1b. The first 2 quinacrine dosing levels were well tolerated. Dose-limiting toxicities were seen in 3 patients treated with quinacrine 200 mg twice daily. Five additional patients tolerated quinacrine 100 mg twice daily without further dose-limiting toxicities, thus establishing the maximum tolerated dose. Seven additional expansion-cohort patients enrolled onto the study before quinacrine manufacturing ceased within the United States. Five patients experienced stable disease, 1 partial response, and 10 disease progression. Median TTP overall was 2.12 months and median overall survival 5.22 months for the 17 patients. CONCLUSION: Capecitabine and quinacrine can be safely administered at the maximum tolerated dose of capecitabine 1000 mg/m2 by mouth twice daily on days 1-14 and quinacrine 100 mg by mouth twice daily on days 1-21 of a 21-day cycle in mCRC patients. Although the expansion study was halted early, TTP was in line with other studies of refractory mCRC, suggesting activity of this regimen in heavily pretreated patients.

Dual Checkpoint Inhibition with Ipilimumab plus Nivolumab After Progression on Sequential PD-1/PDL-1 Inhibitors Pembrolizumab and Atezolizumab in a Patient with Lynch Syndrome, Metastatic Colon, and Localized Urothelial Cancer.

Immune checkpoint blockade (ICB) is an approved therapy for advanced metastatic mismatch repair (MMR)-deficient cancer regardless of tissue of origin. Although therapy is effective initially, recurrence rates are significant, and long-term outcomes remain poor for most patients. It is not currently recommended to give sequential ICB for advanced MMR-deficient colorectal cancer (CRC) or for patients with metastatic cancer from Lynch syndrome. The need for subsequent therapy options in advanced MMR-deficient cancer beyond the first ICB regimen arises in clinical practice, and there are often no effective standard chemotherapies or other targeted therapies. We report the case of a Lynch syndrome patient with metastatic CRC and urothelial cancer who was treated sequentially with pembrolizumab (targeting PD1), atezolizumab (targeting PD-L1), brief rechallenge with pembrolizumab, and finally the combination of ipilimumab (targeting CTLA-4) and nivolumab (targeting PD1). Over a 28-month period the patient experienced prolonged disease control with each different regimen the first time it was given, including metabolic response by positron emission tomography and computed tomography scanning and tumor marker reductions. The case suggests that some patients with advanced MMR-deficient CRC may experience meaningful clinical benefit from multiple sequential ICB regimens, a strategy that can be further tested in clinical trials. KEY POINTS: The case exemplifies clinical benefit from sequential immune checkpoint blockade in a patient with Lynch syndrome with advanced metastatic colorectal cancer and urothelial cancer.Metabolic response, with decreased fluorodeoxyglucose avidity on positron emission tomography and computed tomography, and reductions in tumor markers, such as carcinoembryonic antigen, were helpful in this case to monitor disease status over a 28-month period of therapy.The concept of sequential immune checkpoint blockade in patients with advanced mismatch repair-deficient cancer merits further study to determine which patients are most likely to benefit.

Disease Control With FOLFIRI Plus Ziv-aflibercept (zFOLFIRI) Beyond FOLFIRI Plus Bevacizumab: Case Series in Metastatic Colorectal Cancer (mCRC).

Background: The prognosis of patients with metastatic colorectal cancer (mCRC) is poor, especially after failure of initial systemic therapy. The VELOUR study showed modestly prolonged overall survival (OS) with ziv-aflibercept plus 5-fluorouracil, leucovorin, and irinotecan (zFOLFIRI) vs. placebo+FOLFIRI after progression on 5-fluoruracil, leucovorin, and oxaliplatin (FOLFOX) ± bevacizumab. The utility of zFOLFIRI after bevacizumab+FOLFIRI is unknown and not recommended in NCCN guidelines. We explored whether zFOLFIRI may be active beyond progression on bevacizumab+FOLFIRI. Methods: We undertook a retrospective analysis of patients treated in routine clinical practice. A chart review was conducted for a cohort (N = 19) of advanced cancer patients (18 mCRC) who received zFOLFIRI from 2014 to 2018 at Fox Chase Cancer Center (FCCC). Analysis included time on zFOLFIRI, PFS, OS, CEA trends and adverse events. A second mCRC cohort (N = 26) from the Flatiron Health EHR-derived database treated with zFOLFIRI after prior bevacizumab+FOLFOX and bevacizumab+FOLFIRI was analyzed for time-on-treatment and overall survival. Results: Median age of mCRC cohort at zFOLFIRI treatment was 54 (FCCC; N = 18) and 62 (Flatiron Health-cohort; N = 26). Of 18 FCCC mCRC patients, 1 patient had prior bevacizumab+FOLFOX and ramucirumab+irinotecan prior to zFOLFIRI for 8.5 months. Of 17 FCCC mCRC patients with prior bevacizumab+FOLFIRI who received zFOLFIRI, 13 had mutant-KRAS, 3 WT-KRAS, and one BRAF-V600E. The patient with BRAF-V600E mutation achieved stable disease on zFOLFIRI after multiple BRAF-targeted therapies. One patient (WT-KRAS mCRC) remained on zFOLFIRI for 14 months. Of 14 patients with mutated-KRAS, 8 remained on zFOLFIRI for >5 months including 3 for >15 months. The rate-of-change in CEA measures on zFOLFIRI was significantly different (p = 0.004) between rapid progressors and those with PFS>4 months. For mCRC patients treated with zFOLFIRI in the 3rd line or greater (N = 18), median PFS was 7.1 months (214 days) and median OS was 13.8 months (416 days). Median time-on-treatment with zFOLFIRI in the Flatiron Health cohort was 4.4 months, median OS was 7.8 months, and longest time-on-treatment with zFOLFIRI was 266 days. Conclusions: In these small real-world cohorts, clinical meaningful stable disease and overall survival on zFOLFIRI beyond progression on bevacizumab+FOLFIRI was observed in patients with mCRC. Further exploration of this approach is warranted.

Matrix Metalloproteinase Inhibitors in Cancer Therapy: Turning Past Failures Into Future Successes.

The matrix metalloproteinases (MMP) are a family of proteolytic enzymes that degrade multiple components of the extracellular matrix. A large body of experimental and clinical evidence has implicated MMPs in tumor invasion, neoangiogenesis, and metastasis, and therefore they represent ideal pharmacologic targets for cancer therapy. From the 1990s to early 2000s, synthetic inhibitors of MMPs (MMPI) were studied in various cancer types. Unexpectedly, despite strongly promising preclinical data, all trials were unsuccessful in reducing tumor burden or improving overall survival; in addition, MMPIs had unforeseen, severe side effects. Two main reasons can explain the failure of MMPIs in clinical trials. It has now become apparent that some MMPs have antitumor effects; therefore, the broad-spectrum MMPIs used in the initial trials might block these MMPs and result in tumor progression. In addition, although MMPs are involved in the early stages of tumor progression, MMPIs were tested in patients with advanced disease, beyond the stage when these compounds could be effective. As more specific MMPIs are now available, MMP targeting could be reconsidered for cancer therapy; however, new trials should be designed to test their antimetastatic properties in early-stage tumors, and endpoints should focus on parameters other than decreasing metastatic tumor burden. Mol Cancer Ther; 17(6); 1147-55. ©2018 AACR.

Identifying and managing the adverse effects of immune checkpoint blockade.

Immunotherapy has revolutionized the field of oncology. By inhibiting the cytotoxic T-lymphocyte-associated protein (CTLA-4) and programmed death-1 (PD-1) immune checkpoint pathways, multiple studies have demonstrated greatly improved survival in locally advanced and metastatic cancers including melanoma, renal, lung, gastric, and hepatocellular carcinoma. Trials in other malignancies are ongoing, and undoubtedly the number of drugs in this space will grow beyond the six currently approved by the Food and Drug Administration. However, by altering the immune response to fight cancer, a new class of side effects has emerged known as immune-related adverse events (irAEs). These adverse events are due to overactivation of the immune system in almost any organ of the body, and can occur at any point along a patient's treatment course. irAEs such as endocrinopathies (thyroiditis), colitis, and pneumonitis may occur more commonly. However, other organs such as the liver, heart, or brain may also be affected by immune overactivation and any of these side effects may become life threatening. This review presents an approach to promptly recognize and manage these toxicities, to hopefully minimize morbidity and mortality from irAEs.

Clinical Utilization Pattern of Liquid Biopsies (LB) to Detect Actionable Driver Mutations, Guide Treatment Decisions and Monitor Disease Burden During Treatment of 33 Metastatic Colorectal Cancer (mCRC) Patients (pts) at a Fox Chase Cancer Center GI Oncology Subspecialty Clinic.

Background: Liquid biopsy (LB) captures dynamic genomic alterations (alts) across metastatic colorectal cancer (mCRC) therapy and may complement tissue biopsy (TB). We sought to describe the utility of LB and better understand mCRC biology during therapy. Methods: Thirty-three patients (pts) with mCRC underwent LB. We used permutation-based t-tests to assess associations between alts, and clinical variables and used Kendall's tau to measure correlations. Results: Of 33 pts, 15 were women; 22 had colon, and the rest rectal cancer. Pts received a median of two lines of therapy before LB. Nineteen pts had limited testing on TB (RAS/RAF/TP53/APC), 11 extended NGS, and 3 no TB. Maxpct and alts correlated with CEA (p < 0.001, respectively). In 3/5 pts with serial LB, CEA correlated with maxpct trend, and CT tumor burden. In 6 pts, mutant RAS was seen in LB and not TB; 5/6 had received anti-EGFR therapy prior to LB, suggesting RAS alts developed post-therapy. In two pts RAS-mutated by TB, no RAS alts were detected on LB; these pts had low disease burden on CT at time of LB that also did not reveal APC or TP53 alts. In six patients who were KRAS wt based on TB, post anti-EGFR LB revealed subclonal KRAS mutations, likely a treatment effect. The median number of alts was higher post anti-EGFR LB (n = 12) vs. anti-EGFR naïve LB (n = 22) (9.5 vs. 5.5, p = 0.059) but not statistically significant. More alts were also noted in post anti-EGFR therapy LB vs. KRAS wt anti-EGFR-naïve LB (n = 6) (9.5 vs. 5) among patients with KRAS wild-type tumors, although the difference was not significant (p = 0.182). Conclusions: LB across mCRC therapy detects driver mutations, monitors disease burden, and identifies sub-clonal alts that reflect drug resistance, tumor evolution, and heterogeneity. Interpretation of LB results is impacted by clinical context.

Inhibition of Breast Cancer Metastasis by Presurgical Treatment with an Oral Matrix Metalloproteinase Inhibitor: A Preclinical Proof-of-Principle Study.

Breast cancer has the second highest death toll in women worldwide, despite significant progress in early diagnosis and treatments. The main cause of death is metastatic disease. Matrix metalloproteinases (MMP) are required for the initial steps of metastasis, and have therefore been considered as ideal pharmacologic targets for antimetastatic therapy. However, clinical trials of MMP inhibitors were unsuccessful. These trials were conducted in patients with advanced disease, beyond the stage when these compounds could have been effective. We hypothesized that early treatment with a selective MMP inhibitor between the time of diagnosis and definitive surgery, the so-called "window-of-opportunity," can inhibit metastasis and thereby improve survival. To investigate our hypothesis, we used the 4T1 mouse model of aggressive mammary carcinoma. We treated the animals with SD-7300, an oral inhibitor of MMP-2, -9, and -13, starting after the initial detection of the primary tumor. Seven days later, the primary tumors were excised and analyzed for MMP activity, and the SD-7300 treatment was discontinued. After 4 weeks, the animals were sacrificed and their lungs analyzed histologically for number of metastases and metastatic burden (metastases' area/lung section area). SD-7300 treatment inhibited 70% to 80% of tumor-associated MMP activity (P = 0.0003), reduced metastasis number and metastatic burden by 50% to 60% (P = 0.002 and P = 0.0082, respectively), and increased survival (92% vs. 66.7%; P = 0.0409), relative to control vehicle. These results show that treatment of early invasive breast cancer with selective MMP inhibitors can lower the risk of recurrence and increase long-term disease-free survival. Mol Cancer Ther; 15(10); 2370-7. ©2016 AACR.

MAGE-specific T cells detected directly ex-vivo correlate with complete remission in metastatic breast cancer patients after sequential immune-endocrine therapy.

Studies suggest that conventional cancer therapies given after immunotherapy (IT) can boost antitumor immunity and possibly improve response rates and progression-free survival. We report two cases of metastatic breast cancer with durable complete responses (CRs) after sequential IT and endocrine therapy. Immune analyses of these long-term disease-free breast cancer patients previously treated with imiquimod (IMQ) suggest in-situ vaccination is achieved by topical application of the TLR-7 agonist directly onto tumors. Furthermore, IT-induced antigen-specific T cells were expanded by subsequent endocrine therapy and correlated with response, persisting > 2 years. Our findings therefore suggest that the induction/boosting of polyfunctional tumor antigen-specific T in response to sequential immune endocrine therapy and detected directly ex-vivo can serve as a peripheral blood biomarker for true clinical benefit.

Assessment of personal exposure to ozone in asthmatic children residing in Mexico City / Evaluación de la exposición personal a ozono en niños asmáticos de la Ciudad de México

OBJECTIVE: A study was conducted to evaluate personal ozone exposure (O3p) among asthmatic children residing in Mexico City. MATERIAL AND METHODS: A total of 158 chil-dren were recruited from December 1998 to April 2000. On average, three O3p measurements were obtained per child using passive badges. Time-activity patterns were recorded in a diary. Daily ambient ozone measurements (O3a) were obtained from the fixed station, according to children’s residence. Levels of O3a and ozone, weighted by time spent in different micro-environments (O3w), were used as independent variables in order to model O3p concentrations using a mixed-effects model. RESULTS: Mean O3p was 7.8 ppb. The main variables in the model were: time spent indoors, distance between residence and fixed station, follow-up group, and two interaction terms (overall R²=0.50, p<0.05). CONCLUSIONS: The O3w concentrations can be used as a proxy for O3p, taking into account time-activity patterns and the place of residence of asthmatic Mexican children.

OBJETIVO: Realizamos este estudio para evaluar la exposición personal a ozono (O3p) en niños asmáticos de la Ciudad de México. MATERIAL Y MÉTODOS: Se incluyeron 158 niños entre diciembre de 1998 y abril de 2000. En promedio se obtuvieron tres mediciones por niño, utilizando filtros pasivos para medir O3p. Se caracterizaron los patrones de actividad y las concentraciones ambientales diarias de ozono (O3a) se obtuvieron de estaciones fijas cercanas a la residencia del niño. Los niveles promedio de O3a y las concentraciones ponderadas por el tiempo en diferentes microambientes (O3w) fueron usados como variables independientes para modelar las concentraciones de O3p, utilizando modelos de efectos mixtos. RESULTADOS: La media de O3p fue 7.8 ppb. Las principales variables en el modelo fueron: tiempo en exteriores, distancia, periodo de seguimiento y dos términos de interacción (R²=0.50, p<0.05). CONCLUSIONES: Las concentraciones de O3w pueden usarse como "proxi" de O3p, tomando en cuenta patrones de actividad y lugar de residencia.