Emerging mitochondrial-mediated mechanisms involved in oligodendrocyte development

Oligodendrocytes are the myelinating glia of the central nervous system and are generated after oligodendrocyte progenitor cells (OPCs) transition into pre-oligodendrocytes and then into myelinating oligodendrocytes. Myelin is essential for proper signal transmission within the nervous system and axonal metabolic support. Although the intrinsic and extrinsic factors that support the differentiation, survival, integration, and subsequent myelination of appropriate axons have been well investigated, little is known about how mitochondria-related pathways such as mitochondrial dynamics, bioenergetics, and apoptosis finely tune these developmental events. Previous findings suggest that changes to mitochondrial morphology act as an upstream regulatory mechanism of neural stem cell (NSC) fate decisions. Whether a similar mechanism is engaged during OPC differentiation has yet to be elucidated. Maintenance of mitochondrial dynamics is vital for regulating cellular bioenergetics, functional mitochondrial networks, and the ability of cells to distribute mitochondria to subcellular locations, such as the growing processes of oligodendrocytes. Myelination is an energy-consuming event, thus, understanding the interplay between mitochondrial dynamics, metabolism, and apoptosis will provide further insight into mechanisms that mediate oligodendrocyte development in healthy and disease states. Here we will provide a concise overview of oligodendrocyte development and discuss the potential contribution of mitochondrial mitochondrial-mediated mechanisms to oligodendrocyte bioenergetics and development.

EBUS-guided transbronchial mediastinal cryobiopsy in the diagnosis of mediastinal lesions: safety, feasibility and diagnostic yield – experience in 50 cases

Background

Endobronchial ultrasound guided transbronchial needle aspiration (EBUS-TBNA) is the technique of choice in the study of mediastinal and hilar lesions; however, it can be affected by the insufficiency of intact biopsy samples, which might decrease its diagnostic yield for certain conditions, thus requiring re-biopsies or additional diagnostic procedures such as mediastinoscopy when probability of malignancy remains high.

Objectives

Our objectives were to 1) attempt to reproduce this technique in the same conditions that we performed EBUS-TBNA, that is, in the bronchoscopy suite and under moderate sedation; 2) describe the method used for its execution; 3) determine its feasibility by accessing different lymph node stations applying our method; 4) analyze the diagnostic yield and its complications.

Methods

Prospective study of 50 patients who underwent EBUS-TBNA and EBUS-guided TMC in a single procedure using a 22-G TBNA needle and a 1.1 mm cryo-probe subsequently between January and August 2022. Patients with mediastinal lesions greater than 1 cm were recruited and EBUS-TBNA and TMC were performed in the same lymph node station.

Results

The diagnostic yield was 82% and 96% for TBNA and transbronchial mediastinal cryobiopsy, respectively. Diagnostic yields were similar for sarcoidosis, while cryobiopsy was more sensitive than TBNA in lymphomas and metastatic lymph nodes. As for complications, there was no pneumothorax and in no case was there significant bleeding. There were no complications during the procedure or in the follow-up of these patients.

Conclusions

TMC following our method is a minimally invasive, rapid, and safe technique that can be performed in a bronchoscopy suite under moderate sedation, with a higher diagnostic yield than EBUS-TBNA, especially in cases of lymphoproliferative disorders and mestastatic lymph nodes, or when more biopsy sample is needed for molecular determinations.

Distribution of microplastics present in a stream that receives discharge from wastewater treatment plants

The presence of microplastics (MPs) in freshwater systems that receive discharge of urban effluent implies a great environmental impact. In order to be able to generate proposals that solve this problem, it is necessary to know in detail the contributions of different MPs sources. The aim of this work was to study the contribution of urban sewage discharge to MPs pollution in a stream that runs through a medium-sized city. The spatial distribution of MPs with sizes between 100 μm and 1.5 mm present in surface water was measured and their characteristics, dimensions, shapes and identification were determined. Physical-chemical parameters of the stream water were measured, and a decrease in water quality was found due to wastewater treatment plants. The main source of MPs was effluent from the plants (97% of the total MPs), while the rest came from storm drains and discharge of tributaries. The maximum concentration of MPs found was around 72,000 MP/L (equivalent to 53 million MPs/s), at a point after discharge from both plants. Around 70% of MPs correspond to microfibers with a mean length of around 300 μm and a mean width of around 15 μm, and they are mainly polyethylene fibers. The remaining 30% of MPs are particles with lengths of around 140 μm. The transport of MPs between a point located after discharge of the plants and another point located about 3 km further on was studied, and no significant variation was found in the concentration of MPs. Electrical conductivity was used as a conservative tracer of MPs concentration. This work presents for the first time a detailed analysis of different contributions of MPs to a freshwater system in South America, which receives discharge of wastewater treatment plants, evidencing its important role in pollution.

Sex and gender disparities in patients with advanced gastroesophageal adenocarcinoma: data from the AGAMENON-SEOM registry

Background

Recommendations for research articles include the use of the term sex when reporting biological factors and gender for identities or psychosocial or cultural factors. There is an increasing awareness of incorporating the effect of sex and gender on cancer outcomes. Thus, these types of analyses for advanced gastroesophageal adenocarcinoma are relevant.

Patients and methods

Patients with advanced gastroesophageal adenocarcinoma from the Spanish AGAMENON-SEOM registry treated with first-line combination chemotherapy were selected. Epidemiology, characteristics of the disease, treatment selection, and results were examined according to sex.

Results

This analysis included 3274 advanced gastroesophageal adenocarcinoma patients treated with combination chemotherapy between 2008 and 2021: 2313 (70.7%) men and 961 (29.3%) women. Tumors in females were more frequently HER2-negative (67.8% versus 60.8%; P < 0.0001), grade 3 (45.4% versus 36.8%; P < 0.001), diffuse (43.3% versus 26.5%; P < 0.0001), and signet ring cell histology (40.5 versus 23.9%; P < 0.0001). Peritoneal spread was more common in women (58.6% versus 38.9%; P < 0.0001), while liver burden was lower (58.9% versus 71.1%; P < 0.0001). There were no significant differences in treatment recommendation. Treatment doses, density, and duration were comparable between sexes. Women experienced more diarrhea (46% versus 37%; P < 0.0001), neutropenia (51% versus 43%; P < 0.0001), and anemia (62% versus 57%; P < 0.0001). After a median 59.6-month follow-up [95% confidence interval (CI) 54.5-70.8], there were no statistically significant differences between the sexes in progression-free survival [6.21 months (95% CI 5.8-6.5 months) versus 6.08 months (95% CI 5.8-6.3 months); log-rank test, χ² = 0.1, 1 df, P = 0.8] or in overall survival [10.6 months (95% CI 9.8-11.1 months) versus 10.9 months (95% CI 10.4-11.4 months); log-rank test: χ² = 0.6, 1 df, P = 0.5].

Conclusion

This sex analysis of patients with advanced gastroesophageal adenocarcinoma from the AGAMENON-SEOM registry receiving first-line polychemotherapy found no differences in survival. Although women had worse prognostic histopathology, metastatic disease pattern, and greater toxicity, treatment allocation and compliance were equivalent.

•

Sex and gender are determinants of health inequalities and may affect treatments, tolerability, and therapeutic outcomes.

•

According to sex, subtle biological and clinical differences exist in advanced gastroesophageal adenocarcinoma.

•

Women with advanced gastroesophageal adenocarcinoma experience greater toxicity with therapeutic results comparable with men.

•

Stratification and analysis by sex in studies of gastroesophageal adenocarcinoma should be considered.

O-225 Effects of SARS-Corona virus 2 on IVF treatment parameters: A cohort study of post COVID-19 patients

Study question

Does recovery from SARS–Corona virus 2 (SARS–CoV-2) infection negatively effect IVF cycle parameters?

Summary answer

Female IVF treatment parameters were comparable to the pre-Covid-19 infection cycle performance. Sperm concentration and motility demonstrated lower mean counts following Covid-19 infection.

What is known already

Corona-virus disease-19 (Covid-19) is a global pandemic caused by SARS–Corona virus 2 (SARS–CoV-2). The virus primarily affects the respiratory system, but other systemic and immune mediated effects have been reported. The spikes of SARS-CoV-2 have strong affinity for the Angiotensin converting enzyme (ACE) 2 receptor, leading to an increased Angiotensin II (Ang II) mediated pro-inflammatory response. ACE2 receptors exist in the human reproductive tract (more in males) and pose a regulatory role together with Ang II. So far, reports have been inconsistent regarding testicular effects. Other implications involving fertility and fertility treatment post infection are scarce.

Study design, size, duration

In this retrospective cohort study, IVF cycle performance was compared before and after Corona-virus disease-19. Patients were included only in cases where an IVF cycle was initiated within 3 months of Covid-19 recovery, between March 2020-December 2020.

Participants/materials, setting, methods

The study was conducted in a University affiliated IVF unit. Post Covid- 19 cycle parameters were compared to previous cycles of the same individual prior to infection. If previous cycles were not available, parameters were compared to non-exposed patients of same age, same treatment and identical indication. Sperm concentration and motility were compared before and after infection. Non exposure was defined by a lack of past Covid-19 diagnosis and a negative PCR throughout the treatment.

Main results and the role of chance

All together, including the matched cycles, we compared 40 cycles which started within 3 months of recovery: 26 fresh stimulation cycles and 14 frozen thawed transfer cycles. In 28 of these cycles the patient could serve as its own control. Mean age for the female partner was 33.2 years ±6.5 years. Eight male partners presented post infection and provided fresh samples for a cycle involving fertilization. We compared stimulation parameters including maximal Estradiol level, stimulation length, FSH dosage, number of oocytes retrieved, fertilization rates, number of embryos created, high quality embryo number and endometrial thickness. All of these were comparable to non-exposed cycles (generalized estimating equations, p values &gt;0.1). No complications were recorded, specifically no thromboembolic events or respiratory complications. A total of 8 patients conceived: 1 was a chemical pregnancy, 1 extra-uterine pregnancy, 3 miscarriages and 3 ongoing, of those 1 was complicated by early bleeding. Male sperm analyses showed a trend towards lower post disease parameters, not reaching a statistical significance: 23mil/ml compared to 13.6 and 20.7% progressive motility compared to 12.3% (p values 0.09 and 0.17, respectively).

Limitations, reasons for caution

Current results are based on a small sample size, still insufficient for deducing definite conclusions or guidelines. Pregnancy outcome following IVF treatment in Covid-19 recoverees should further be studied. By the time of the conference, the number of cases is expected to be significantly higher.

Wider implications of the findings

This study provides preliminary data regarding the effects of SARS-COV-2 infection on IVF treatment outcomes. Despite the small sample size, treatment parameters seem unaffected, however, sperm performance seems to be compromised. Health policy and patients’ decisions regarding whether or not to postpone IVF procedures necessitates additional data.

Trial registration number

Not applicable - retrospective

OP0234 RISK OF ACUTE MYOCARDIAL INFARCTION AMONG NEW USERS OF CHONDROITIN SULPHATE: A NESTED CASE-CONTROL STUDY

Background:

There is some evidence from epidemiological studies suggesting that CS and glucosamine could play a role in cardiovascular disease (CVD) prevention (1-4).Studies to date have included prevalent users, therefore a bias that overestimates protection cannot be excluded.

Objectives:

To test the hypothesis that chondroitin sulphate (CS) or glucosamine reduce the risk of acute myocardial infarction (AMI).

Methods:

Case-control study nested in a primary cohort composed of patients aged 40 to 99 years, with at least one year of follow-up in the BIFAP database during the 2002-2015 study period. From this cohort of patients, we identified incident cases of AMI and randomly selected five controls per case, matched by exact age, gender, and index date. Adjusted odds ratios (AOR) and their corresponding 95% confidence interval (CI)) were calculated through a conditional logistic regression. Only new users of CS or glucosamine were considered.

Results:

A total of 23,585 incident cases of AMI and 117,405 controls were included. The mean age was 67.0 (SD 13.4) years and 71.75% were male, in both groups. 558 (2.37%) cases and 3,082 (2.62%) controls used or had used CS. The current use of CS was associated with a lower risk of AMI (AOR 0.57; 95%CI: 0.46–0.72) and disappeared after discontinuation (recent and past users). The reduced risk among current users was observed in both short-term (<365 days AOR 0.58; 95%CI: 0.45-0.75) and long-term users (>364 days AOR 0.56; 95%CI 0.36-0.87), in both sexes (men, AOR=0.52; 95%CI:0.38-0.70; women, AOR=0.65; 95%CI: 0.46-0.91), in individuals over or under 70 years of age (AOR=0.54; 95%CI:0.38-0.77, and AOR=0.61; 95%CI:0.45-0.82, respectively) and in individuals at intermediate (AOR=0.65; 95%CI:0.48-0.91) and high cardiovascular risk (AOR=0.48;95%CI:0.27-0.83), but not in those at low risk (AOR=1.11; 95%CI:0.48-2.56). In contrast, the current use of glucosamine was not associated with either increased or decreased risk of AMI (AOR= 0.86; CI95% 0.66-1.08)

Conclusion:

Our results support a cardioprotective effect of CS, while no effect was observed with glucosamine. The highest protection was found among subgroups at higher cardiovascular risk.

References:

[1]Ma H, Li X, Sun D, Zhou T, Ley SH, Gustat J, et al. Association of habitual glucosamine use with risk of cardiovascular disease: prospective study in UK Biobank. BMJ. 2019;365(Journal Article):l1628.

[2]de Abajo FJ, Gil MJ, Garcia Poza P, Bryant V, Oliva B, Timoner J, et al. Risk of nonfatal acute myocardial infarction associated with non-steroidal antiinflammatory drugs, non-narcotic analgesics and other drugs used in osteoarthritis: a nested case-control study. PharmacoepidemiolDrug Saf. 2014;23(11):1128–38.

[3]Li Z-H, Gao X, Chung VC, Zhong W-F, Fu Q, Lv Y-B, et al. Associations of regular glucosamine use with all-cause and cause-specific mortality: a large prospective cohort study. Ann Rheum Dis. 2020 Apr 6;annrheumdis-2020-217176.

[4]King DE, Xiang J. Glucosamine/Chondroitin and Mortality in a US NHANES Cohort. J Am Board Fam Med. 2020 Dec;33(6):842–7.

Disclosure of Interests:

Ramón Mazzucchelli Speakers bureau: UCB, Lilly, Grant/research support from: Pfizer, Roche, Amgen, Sara Rodriguez-Martin: None declared, Alberto García-Vadillo: None declared, Miguel Gil: None declared, Antonio Rodríguez-Miguel: None declared, Diana Barreira-Hernández: None declared, Alberto García-Lledó: None declared, Francisco de Abajo: None declared

Risk of acute myocardial infarction among new users of bisphosphonates: a nested case-control study

OBJECTIVE

To test the hypothesis that bisphosphonates reduce AMI risk among new users and to assess whether the effect depends on the duration of treatment.

METHODS

Case-control study nested in a primary cohort composed of patients aged 40 to 99 years, with at least 1-year registry in the BIFAP database throughout the study period 2002-2015. Out of this cohort, incident AMI cases were identified and five controls per case were randomly selected, matched by exact age, sex, and index date. The association of AMI with current, recent and past use of bisphosphonates was assessed by computing adjusted odds ratios (AOR) and their corresponding 95% confidence interval (CI) through an unconditional logistic regression. Only initiators of bisphosphonates were considered.

RESULTS

A total of 23,590 cases of AMI and 117,612 controls were included. The mean age was 66.8 (SD 13.4) years, and 72.52% was male, in both groups. About 276 (1.17%) cases and 1458 (1.24%) controls were current users of bisphosphonates yielding an AOR of 0.98 (95% CI 0.854-1.14). Recent and past use were not associated with a reduced risk, either, nor was it found a reduction with treatment duration (AOR less than 1 year = 0.92; 95% CI 0.73-1.15; AOR more than 1 year = 1.03; 95% CI 0.86-1.23). Stratified analysis by age, sex and background cardiovascular risk did not show an effect modification by these variables.

CONCLUSION

The results do not support a cardioprotective effect of bisphosphonates regardless of the duration of treatment, age, sex or background cardiovascular risk. However, a small protective effect could have been masked if patients with osteoporosis have had a background higher risk of AMI.

What has changed during the state of emergency due to COVID-19 on an Academic Urology Department of a Tertiary Hospital in Portugal

Objetivo

Comparar la actividad del Servicio de Urología de un Hospital Universitario Portugués durante el estado de alarma y el periodo equivalente del año anterior. Comparamos el número de consultas electivas y pruebas diagnósticas urológicas, el número y el tipo de cirugías electivas, así como las características demográficas de los pacientes y las principales causas de ingreso al Servicio de Urgencias (SU) de Urología durante los dos periodos mencionados.

Materiales y métodos

Los datos de 691 pacientes que acudieron a urgencias desde el 18 de marzo de 2020 hasta el 2 de mayo de 2020 -y del mismo periodo del año anterior- se recogieron del software medico institucional. Los datos recopilados fueron edad, sexo, fecha de visita al servicio de urgencias, derivación desde otros hospitales, color del triaje, causa del ingreso, diagnóstico al alta y la necesidad de cirugía de urgencia u hospitalización. Con la intención de identificar las asociaciones entre las variables demográficas y clínicas con el hecho de haber sido sometido a una cirugía de urgencia (variable), se aplicaron modelos de regresión logística.

Resultados

El análisis multivariante mostró asociación entre el sexo del paciente con el hecho de ser sometido a una cirugía, con una disminución del 65,6% en las probabilidades para el género masculino. El periodo (COVID versus sin-COVID) no mostró una asociación significativa con la cirugía.

Conclusión

Nuestro departamento experimentó una reducción importante en la actividad. También observamos una reducción de las causas urgentes para acudir a los servicios de urgencias considerados menos graves. El porcentaje de casos que requirieron cirugía de urgencia y hospitalización fue mayor durante el periodo COVID.

Factors that influence the response time in STEMI patients in Lisbon 2017

The success of the ST-segment elevation myocardial infarction (STEMI) approach is based on early diagnosis and on the institution of timely reperfusion therapy, with response times remaining variable. The objective of this study was to determine which factors influenced the response time to patients with STEMI until the treatment with coronary reperfusion from the prehospital service or the emergency room in three hospitals in the greater Lisbon area in 2017. An epidemiological, cross-sectional, retrospective, descriptive study with an analytical component was performed, with data from the National Institute of Medical Emergency (INEM) and clinical trials of patients. Patients who were not referred to these hospitals were excluded. Univariate statistical analysis was performed, as well as c2 tests, t-student and logistic regression model (r &lt; 0.05). The population included 95 patients, the majority being male (67.4%), and with a mean age of 63.8 years. 61.1% were hypertensive and the majority (87.4%) had no signs of previous heart failure. The mean door-to-balloon time was 159 minutes, with 57.4% showing time greater than 120 minutes. In patients in whom the INEM Coronary Greenway was activated, mean door-to-balloon time was 99 minutes. Diagnostic, symptom-admission and transport times showed a statistically significant association with the door-to-balloon time in the bivariate analysis. The times are fulfilled in the prehospital service, but in the hospital, services can be improved through the early accomplishment of electrocardiogram and the optimization of interhospital transport.

Key messages

Reducing ECG time and inter-hospital transport time improves STEMI response and outcome. Time is muscle is the main message for de concern of identifying influence factors of STEMI response time.

SAT0446 RISK OF ACUTE MYOCARDIAL INFARCTION (AMI) AMONG NEW USERS OF BISPHOSPHONATES: A NESTED CASE-CONTROL STUDY

Background:

Evidence suggest that bisphosphonates (BF) may inhibit atherosclerosis and vascular calcification. In several small-scale clinical trials, BF improved some intermediate targets of atherosclerosis. Observational studies found a lower risk of Acute Myocardial Infarction (AMI) or stroke among BF users compared to non-users. While this epidemiological evidence suggests that BF may protect against cardiovascular events a “prevalent user bias” cannot be excluded.

Objectives:

To analyze the hypothesis that BF reduce de risk of AMI in new users and assess whether the effect depends on the duration of treatment.

Methods:

Case-control study nested in a primary cohort composed of patients aged 40 to 99 years, with at least one year of follow-up in the BIFAP database during the 2002-2015 study period. From this cohort of patients, we identified incident cases of AMI and randomly selected five controls per case, matched by exact age, gender, and index date. Adjusted odds ratios (AOR) and their corresponding 95% confidence interval (CI) were calculated through an unconditional logistic regression. Only new users of BF were considered.

Results:

A total of 23,590 cases of IAM and 117,612 controls were included. The mean age was 66.8 (SD 13.4) years and 72.52% were male, in both groups. 584 (2,47%) cases and 2,892 (2.46%) controls used or had used some bisphosphonate. The use of BF was not associated with a lower risk of IAM (AOR 0.97; 95%CI: 0.84–1.13). Nor was it associated with the duration of treatment (AOR less than 1 year = 0.91; 95%CI: 0.72-1.15);AOR more than 1 year= 1.01; 95%CI: 0.84-1.21). The stratified analysis by age and sex also did not show either a protective effect of BF. Detailed results by BF type are shown in the following table:

Cases (%)Controls (%)Non-adjusted ORAdjusted ORN=23590N=117612(95% CI)(95% CI)BisphosphonatesNon users23006 (97.52)114720 (97.54)1 (Ref.)1 (Ref.)Current276 (1.17)1458 (1.24)0.93 (0.81-1.06)0.97 (0.84-1.13)Recent109 (0.46)478 (0.41)1.13 (0.92-1.40)1.11 (0.89-1.40)Past199 (0.84)956 (0.81)1.04 (0.89-1.21)1.01 (0.86-1.20)Alendronic acidNon users23338 (98.93)116421 (98.99)1 (Ref.)1 (Ref.)Current88 (0.37)469 (0.40)0.91 (0.72-1.15)0.97 (0.76-1.24)Recent46 (0.19)201 (0.17)1.17 (0.84-1.61)1.18 (0.83-1.66)Past118 (0.50)521 (0.44)1.12 (0.91-1.37)1.13 (0.91-1.40)Alendronic acid+VitDNon users23509 (99.66)117155 (99.61)1 (Ref.)1 (Ref.)Current34 (0.14)207 (0.18)0.81 (0.56-1.17)0.89 (0.60-1.31)Recent15 (0.06)77 (0.07)0.94 (0.54-1.63)0.71 (0.40-1.29)Past32 (0.14)173 (0.15)0.92 (0.63-1.35)0.83 (0.56-1.25)Alendronic acid (all)Non users23274 (98.66)116057 (98.68)1 (Ref.)1 (Ref.)Current122 (0.52)671 (0.57)0.89 (0.73-1.08)0.95 (0.77-1.18)Recent58 (0.25)261 (0.22)1.11 (0.83-1.48)1.03 (0.76-1.39)Past136 (0.58)623 (0.53)1.08 (0.89-1.31)1.05 (0.86-1.29)Ibandronic acidNon users23504 (99.64)117174 (99.63)1 (Ref.)1 (Ref.)Current41 (0.17)216 (0.18)0.96 (0.68-1.34)1.00 (0.70-1.42)Recent18 (0.08)69 (0.06)1.24 (0.74-2.09)1.38 (0.80-2.36)Past27 (0.11)153 (0.13)0.87 (0.57-1.31)0.88 (0.57-1.35)Risedronic acidNon users23355 (99.00)116446 (99.01)1 (Ref.)1 (Ref.)Current102 (0.43)527 (0.45)0.95 (0.76-1.18)0.99 (0.79-1.25)Recent47 (0.20)186 (0.16)1.27 (0.92-1.75)1.17 (0.83-1.66)Past86 (0.36)453 (0.39)0.94 (0.75-1.19)0.93 (0.72-1.19)

Conclusion:

Our results do not support a cardioprotective effect of BF, regardless of the duration of treatment, age, sex or background cardiovascular risk.

Disclosure of Interests:

None declared

Abstract P2-06-17: A novel interaction of AURKA with MAPK pathway in breast cancer cells as a potential therapeutic target

Background: Aurora A (AURKA) is a mitotic kinase responsible for centrosome segregation and mitotic spindle formation. In normal cells, expression of AURKA is highly regulated and is predominantly restricted to G2/M phases of the cell cycle. Unlike healthy cells, cancer cells overexpress AURKA through all phases of the cell cycle resulting in the acquisition of alternate non-mitotic functions. Little is known about cellular functions regulated by AURKA and its interaction with other signaling molecules. Here, we report a novel interaction between AURKA and the mitogen-activated protein kinase (MAPK) pathway at the level of MEK1 in breast cancer cells. This interaction may serve as a novel target as well as demonstrate by an additive cytotoxic effect of AURKA- and MEK1/2-specific inhibitors against estrogen positive (ER+) and triple negative breast cancer (TNBC) cells.

Results: We show that treatment of ER+ HER2- MCF-7, ER- HER2+ SKBR3 and ER- HER2- BT549 cells with AURKA specific inhibitors alisertib, MK8745 and Aurora A Inhibitor I resulted in over 2-fold increase in relative levels of poMEK1/2 and poERK1/2 compared to untreated controls. The activation of the MAPK pathway was rapid with changes seen within 5 min after treatment with AURKA inhibitors and was sustained for at least 48 hours. Treatment with the pan RAF inhibitor TAK-632 did not diminish alisertib-induced poERK and poMEK1/2. Alternatively, treatment with the MEK1/2 specific inhibitor PD0325901 completely abrogated alisertib-induced phosphorylation of MEK1/2 and ERK1/2. In situ proximity ligation and pull down assays demonstrated AURKA and MEK1/2 direct interaction. In vitro kinase assay showed direct phosphorylation of MEK1 by AURKA. Combined treatment of alisertib and PD0325901 in vitro revealed significant additive cytotoxic effect in MCF-7 and BT549 cells when compared to either agent used alone (p&lt; 0.008 and p&lt;0.011; p &lt;0.04 and p&lt;0.028) with early trend toward significance in survival in a BT549 xenograft breast cancer in vivo model.

Conclusions: Our data shows a novel AURKA-MEK1 interaction in breast cancer cells. In depth in vivo analysis is ongoing. The results reveal a promising new strategy for the treatment TNBC patients using a combination of AURKA and MEK1/2 inhibitors.

Citation Format: Gandhi S, Gil M, Khoury T, Takabe K, Puzanov I, Gelman I, D'Assoro A, Opyrchal M. A novel interaction of AURKA with MAPK pathway in breast cancer cells as a potential therapeutic target [abstract]. In: Proceedings of the 2018 San Antonio Breast Cancer Symposium; 2018 Dec 4-8; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2019;79(4 Suppl):Abstract nr P2-06-17.

Abstract P6-09-04: Predictive factors for considering to avoid axillar lymphadenectomy in selected node positive breast cancer patients after neoadjuvant chemotherapy

Background:

To perform a systematic axillar lymphadenectomy (ALND) in clinical node positive (N+) patients after neoadjuvant chemotherapy (NACT) is currently under discussion. We aimed to study which factors are related to a pathological complete axillar response (ypN0) after NACT in order to select which patients could benefit from a sentinel lymph node biopsy without interfering with survival.

Material and methods

N+ patients who underwent ALND after NACT between June 2008 and December 2016 were retrospectively analyzed. Clinical features, molecular and histological factors, recurrence and specific mortality rates were compared between patients achieving a complete pathological axillary response vs not (ypN0 vs ypN+).

Results

345 N+ patients were reviewed. After NACT, 137 (39.6%) become ypN0[CF1] , 9 (2.6%) ypN1 mic, 113 (32.7%) ypN1, 60 (17.3%) ypN2 and 22 (6.4%) N3. Univariate analysis results regarding the predictive factors for ypN0 are detailed in [table 1]. Multivariate analyses showed molecular subtype (TN and Her2+) and clinical response as independent predictors of ypN0 [table 2]. After a mean follow-up of 58 months, overall survival was statistically superior in ypN0 vs ypN1 (p= 0.001).

Table 1.Predictive factors for ypN0 YpN0 (n = 137)YpN+ (n = 208)pAge (mean, years)58.3 ± 13.2758.59 ± 12.340.799BMI (mean)27.8±5.4927.8±5.360.973Dosis of QT (median)(%)  0.575IIA6 (31.6)13 (68.4) IIB71 (39.3)110 (60.8) IIIA28 (36.8)48 (63.2) IIIB24 (43.6)31 (56.4) IIIC7 (58.3)5 (41.7) Radiological image(%)  0.930Nodule77 (38.1)125 (61.9) Non-mass distortion10 (43.5)13 (56.5) Radiological size (median)32 (0-115)29 (0-130)0.246Suspicious a-LN by US(%)  0.486130 (30.9)37 (24.3) 25 (5.2)14 (9.2) &gt;257 (58.8)91 (59.9) Histological subtype(%)  0.093Invasive Ductal Carcinoma133 (40.9)192 (59.1) Invasive Lobular Carcinoma2 (20)8 (80) Others2 (22.2)7 (78.8) Nottingham grade(%)  &lt;0.001G11 (6.2)15 (93.8) G244 (28.6)110 (71.4) G386 (53.4)75 (46.6) Molecular-like subtype(%)  &lt;0.001Luminal A-like2 (5.3)36 (94.7) Luminal B-like (Her2 -)21(18.1)95 (81.9) Luminal B-like (Her2 +)40 (63.5)23 (36.5) HER-2 enriched (non luminal)43 (74.1)15 (25.9) Triple Negative31 (44.9)38 (55.1) Vascular invasion19 (42.2)26 (57.8)0.889Clinical Response(%)  &lt;0.001Complete61 (75.3)20 (24.7) Partial69 (31.8)148 (68.2) No response6 (20.7)23 (79.3) Progression1 (10)9 (90) Percentage are given per row.

Table 2.Multivariate analysis logistic regression of clinical predictive factors of ypN0. OR95% Confidence Intervalp valueMolecular subtype   No-luminal vs Luminal7,7483,913-15,343&lt;0,001Clinical response   Response vs not response6,8491,834-25,5710,04OR: Odd ratio. No-luminal includes: luminal B (HER2 +), HER2 Henriched and triple negative. Luminal includes: Luminal A and Luminal B (HER2 -).

Conclusions

A remarkable percentage of N+ became ypN0 after NATC. Molecular subtype and complete clinical response were independent predictive factors of ypN0. We propose to offer the benefit of a targeted axillary procedure in those patients.

Citation Format: Fernandez-Gonzalez S, Falo Zamora C, Nuñez D, Vethencourt A, Pla MJ, Soler T, Guma A, Perez X, Gil M, Ponce J, Garcia A. Predictive factors for considering to avoid axillar lymphadenectomy in selected node positive breast cancer patients after neoadjuvant chemotherapy [abstract]. In: Proceedings of the 2018 San Antonio Breast Cancer Symposium; 2018 Dec 4-8; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2019;79(4 Suppl):Abstract nr P6-09-04.

Abstract P2-08-58: Prognostic factors of survival in node positive breast cancer patients after neoadjuvant chemotherapy in a large series after 5y follow-up: Can response overcome the poor prognosis of nodal stage?

Background: Status of the axilla is one of the most significant prognostic factors in breast cancer (BC) patients. On the other hand, response to neoadjuvant chemotherapy (NACT) is related to survival. The aim of the present study is to analyze which prognostic factors impact most on Node positive (N+) BC patient survival after NATC. Material and methods: Retrospective analyses on a series of N+ BC patients treated with NATC based on anthracyclines and taxanes +/- trastuzumab if HER2 positive tumors, between June 2008 and December 2016. Clinical, radiological and pathological outcomes have been evaluated. Residual cancer burden (RCB) 1 and the neoadjuvant response index (INR) 2 have been recorded. Survival was calculated with Kaplan-Meier survival curve since the start of NATC to the first documented disease recurrence (DFS) or death (OS). Hazard ratios (HRs) with 95% CIs were estimated with cox proportional hazards regression analysis and subgroups were compared with a two-sided log-rank test. Results: A total of 345 N+ BC patients were included. Pathological complete response was achieved in 72 (20.8%) patients. After NACT, 137 (39.6%) become ypN0, 9 (2.6%) ypN1 mic, 113 (32.7%) ypN1, 60 (17.3%) ypN2 and 26 (7.6%) N3. Those independent predictive factor of ypN0 were molecular subtype (TN and Her2+) with OR: 7.7, p&lt;0.001 and clinical response with OR 6.88, p: 0.04. At a mean follow-up of 58 months there have been 73 (21.1%) recurrences: 9 (2.3%) local, 45 (13%) systemic, 15 (4.3%) systemic+ local, 3 (0.9%) axilla, 1 (0.3%) supraclavicular. The estimated 5y OS was 87.8%. The univariate analysis according to DSF is detailed in Table1.

Adjusted univariate anaalysis cox regression of clinical and pathological factors of desease free survivalBMI10.989-1.010.963AGE0.9960.953-1.0420.876Dose NATC0.9940.979-1.0080.402Clinical Stage1.4021.077-1.8260.012Rx Image1.260.803-1.9940.311Rx size1.0090.995-1.0240.217Number suspicious ALN1.0950.801-1.4970.57Molecular subtype TN,HER20.8800.534-1.450.616Nottinghan grade1.0460.753-1.4530.789Histological subtype1.4651.044-2.0570.27MOlecular subtype1.1510.956-1.3850.137Vascular invasion1.6761.137-24710.009Clinical response2.3691.709-3.284&lt;0.001Fibrosis tumor bed0.980.972-0.989&lt;0.001Nodal fibrosis&gt;50%1.7950.874-3.6860.111Pathological tumoral response1.6861.175-2.4180.005ypN03.561.853-6.838&lt;0.001NRI0.330.192-0.565&lt;0.001RCB1.2741.106-1.4680.001

In the multivariate model those parameters that were independently prognostic were clinical response HR: 5.44 (IC95% 2.275-13.042, p&lt;0.001) and clinical stage HR: 2.364 (IC95% 1.018-5.490, p: 0.045). Conclusions: The most significant prognostic factor in our N+ series was response to NATC, followed by clinical stage. Those independently predictive factors of axillar response (ypN0) were molecular subtype (TN and Her2+) and clinical response. In conclusion, in those patients with chemo sensitive tumors, lymphadenectomy could be safely spared with a more selective axillary approach.

Citation Format: Fernandez S, Garcia A, Vethencourt A, Vazquez S, Petit A, Pla MJ, Ortega R, Pérez J, Gil M, Ponce J, Pernas S, Lopez A, Falo C. Prognostic factors of survival in node positive breast cancer patients after neoadjuvant chemotherapy in a large series after 5y follow-up: Can response overcome the poor prognosis of nodal stage? [abstract]. In: Proceedings of the 2018 San Antonio Breast Cancer Symposium; 2018 Dec 4-8; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2019;79(4 Suppl):Abstract nr P2-08-58.

Benefits and risks of adjuvant treatment with zoledronic acid in stage II/III breast cancer. 10 years follow-up of the AZURE randomized clinical trial (BIG 01/04)

Adjuvant bisphosphonates improve disease outcomes in postmenopausal early breast cancer (EBC) but the long-term effects are poorly described. The AZURE trial (ISRCTN79831382) was designed to determine whether adjuvant zoledronic acid (ZOL) improves disease outcomes in EBC. Previous analyses showed no effect on overall outcomes but identified benefits in postmenopausal women. Here we present the long-term risks and benefits of adjuvant ZOL with 10-years follow-up.

Patients and methods

3360 patients with stage II/III breast cancer were included in an academic, international, phase III, randomized, open label trial. Patients were followed up on a regular schedule until 10 years. Patients were randomized on a 1:1 basis to standard adjuvant systemic therapy +/− intravenous ZOL 4 mg every 3–4 weeks x6, and then at reduced frequency to complete 5 years treatment. The primary outcome was disease free survival (DFS). Secondary outcomes included invasive DFS (IDFS), overall survival (OS), sites of recurrence, skeletal morbidity and treatment outcomes according to primary tumor amplification of the transcription factor, MAF. Pre-planned subgroup analyses focused on interactions between menopausal status and treatment effects.

Results

With a median follow up of 117 months [IQR 70.4–120.4), DFS and IDFS were similar in both arms (HR_DFS= 0.94, 95%CI = 0.84–1.06, p = 0.340; HR_IDFS= 0.91, 95%CI = 0.82–1.02, p = 0.116). However, outcomes remain improved with ZOL in postmenopausal women (HR_DFS= 0.82, 95%CI = 0.67–1.00; HR_IDFS= 0.78, 95%CI = 0.64–0.94). In the 79% of tested women with a MAF FISH negative tumor, ZOL improved IDFS (HR_IDFS= 0.75, 95%CI = 0.58–0.97) and OS HR_OS= 0.69, 95%CI = 0.50–0.94), irrespective of menopause. ZOL did not improve disease outcomes in MAF FISH + tumors. Bone metastases as a first DFS recurrence (B_DFS) were reduced with ZOL (HR_B-DFS= 0.76, 95%CI = 0.63–0.92, p = 0.005). ZOL reduced skeletal morbidity with fewer fractures and skeletal events after disease recurrence. 30 cases of osteonecrosis of the jaw in the ZOL arm (1.8%) have occurred.

Conclusions

Disease benefits with adjuvant ZOL in postmenopausal early breast cancer persist at 10 years of follow-up. The biomarker MAF identified a patient subgroup that derived benefit from ZOL irrespective of menopausal status.

Fraction of high-grade cervical intraepithelial lesions attributable to genotypes targeted by a nonavalent HPV vaccine in Galicia, Spain

Background

Human papillomavirus (HPV) bivalent and quadrivalent vaccines have been widely implemented in worldwide organized immunization programs. A nonavalent HPV vaccine is now available in several countries. The objective was to describe the fraction of squamous non-invasive high-grade cervical intraepithelial lesions attributable to genotypes targeted by bi-quadrivalent vaccines and by nonavalent vaccine according to age and diagnosis in women living in the city of Vigo (Galicia, Spain).

Methods

Cervical scrapings (2009–2014) of women with histological diagnosis of cervical intraepithelial neoplasia grade 2 (CIN2, n = 145) and grade 3-carcinoma in situ (CIN3-CIS, n = 244) were tested with Linear Array HPV Genotyping test (Roche diagnostics, Mannheim, Germany). Hierarchical estimation of the fraction attributable to HPV 16/18 or HPV 31/33/45/52/58 detected alone or in combination was calculated. Absolute additional fraction attributable to genotypes targeted by nonavalent vaccine compared to genotypes targeted by bi-quadrivalent vaccines was calculated as the increment of attributable cases with respect to all studied cases. Age group 1, 2 and 3 included women 18 to 34, 35–44 and ≥45 years old, respectively. EPIDAT 3.1 was used.

Results

Fraction attributable to genotypes targeted by bi-quadrivalent vaccines was 59% CIN2 vs. 69% CIN3-CIS (p < 0.001). It was 63/51/50% of CIN2 and 78/66/45% of CIN3-CIS in age group 1, 2, 3, respectively. Fraction attributable to genotypes targeted by nonavalent vaccine was 86% CIN2 and 86% CIN3-CIS. It was 87/91/75% of CIN2 and 90/86/76% of CIN3-CIS in age group 1, 2, 3, respectively. Fraction attributable to genotypes targeted by these vaccines tended to decrease as age increased (p-trend <0.05). Globally, absolute additional attributable fraction was 16%, 26% and 29% in age group 1, 2 and 3, respectively (p < 0.005).

Conclusions

Absolute additional fraction of CIN2 and CIN3-CIS attributable to genotypes targeted by nonavalent vaccine was observed in women of any age, especially in those over 35 years old.

Transbronchial cryobiopsy in interstitial lung disease: experience in 106 cases - how to do it

Transbronchial biopsy using forceps (TBB) is the first diagnostic technique performed on patients with interstitial lung disease (ILD). However, the small size of the samples and the presence of artefacts in the tissue obtained make the yield variable. Our objectives were 1) to attempt to reproduce transbronchial cryobiopsy under the same conditions with which we performed conventional TBB, that is, in the bronchoscopy unit without intubating the patient and without fluoroscopy or general anaesthesia; 2) to describe the method used for its execution; and 3) to analyse the diagnostic yield and its complications. We carried out a prospective study that included 106 patients with clinical and radiological features suggestive of ILD who underwent cryo-transbronchial lung biopsy (cryo-TBB) under moderate sedation without endotracheal intubation, general anaesthesia or use of fluoroscopy. We performed the procedure using two flexible bronchoscopes connected to two video processors, which we alternated until obtaining the number of desired samples. A definitive diagnosis was obtained in 91 patients (86%). As for complications, there were five pneumothoraces (4.7%) and in no case was there severe haemorrhage or exacerbation of the underlying interstitial disease. Cryo-TBB following our method is a minimally invasive, rapid, safe and economic technique that can be performed in a bronchoscopy suite under moderate sedation without the need for intubating the patient or using fluoroscopy and without requiring general anaesthesia.

Abstract P6-11-10: Preclinical efficacy of the novel PIM2 kinase inhibitor, JP11646 in triple negative breast cancer models

Background: Triple negative breast cancer (TNBC) patients have poorer prognosis and there remains a lack of novel targeted therapies for their treatment. PIM2 (Proviral Integrations of Moloney virus 2) belongs to a family of three kinases that have been implicated in the survival and progression of hematologic malignancies and solid tumors. PIM2 has been linked to epithelial to mesenchymal transition in TNBC, which can lead to metastasis and chemotherapeutic resistance. We hypothesized that PIM2 may present as a therapeutic target in TNBC.

Materials and Methods: The study involved both in vitro and in vivo studies involving a novel PIM2 inhibitor JP11646 (obtained from Jasco Pharmaceuticals). TNBC cell lines MDA-MB-231 and BT-549 were obtained for our in vitro studies. Cell viability was evaluated using MTT assay. Western Blot assay was used to evaluate relative protein expression. For in vivo studies, female SCID mice were inoculated in the mammary fat pads with 1 × 106 MDA-MB-231 cells. When tumor volumes reached 100 mm3, the mice were treated with JP11646 at the dosage 15mg/kg intraperitoneally for 2 consecutive days weekly for total of 4 weeks as determined from previous experiments. Control animals received vehicle only. The mice were euthanized once tumors reached ∼1,700 mm3.

Results: BT-549 cells treated in vitro with 3 different available PIM kinase inhibitors AZD 1208, LGB321 and JP12641 showed only modest reduction in cell viability. However, treatment of both MDA-MB-231 and BT-549 with JP 11646 demonstrated significant reduction in cell viability with IC50 ranging from 40 to 71.6 nM. Treatment with JP11646 demonstrated a novel mechanism of action resulting in downregulation of PIM2 in both cell lines. Treatment with JP11646, but not other PIM kinase inhibitors, resulted in activation of apoptosis as measured by cleaved PARP (cPARP) levels. Anti-PIM2 siRNA treatment but not treatment with non-specific PIM kinase inhibitor AZD1208 resulted in cPARP induction. Inhibition of proteolysis by bortezomib resulted in preservation of PIM2 and inhibition of apoptosis as demonstrated by decreased cPARP levels after treatment with JP11646. PIM2 over-expressing clone of MDA-MB-231 cells showed enhanced proliferation and migration properties both in vitro and in vivo.Treatment of mice with orthotopically implanted MDA-MB-231 tumors with JP 11646 resulted in significant reduction in the tumor growth (p=0.0019) and increased overall survival (p=0.018) as compared to control mice.

Conclusions: PIM2 upregulation in TNBC cell line resulted in more aggressive phenotype. JP11646, through novel mechanism of action resulting in degradation of PIM2, showed robust activity in TNBC cell lines both in vitro and in vivo. Further correlative studies in tumors harvested from in vivo experiments are ongoing. These results encourage further exploration of use of JP11646 as a targeted agent in treatment of TNBC.

Citation Format: Mehta R, Kothai Guruswamy Sangameswaran D, Bezbatchenko K, Moore J, Gil M, Khoury T, Baldino C, Caserta J, Fetterly, Jr. G, Lee K, Adjei A, Opyrchal M. Preclinical efficacy of the novel PIM2 kinase inhibitor, JP11646 in triple negative breast cancer models [abstract]. In: Proceedings of the 2016 San Antonio Breast Cancer Symposium; 2016 Dec 6-10; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2017;77(4 Suppl):Abstract nr P6-11-10.

Abstract P6-17-01: Adjuvant treatment with zoledronic acid (ZOL) in stage II/III breast cancer. The AZURE trial (BIG 01/04) 10 year follow-up

This abstract was not presented at the symposium.

Abstract P4-21-32: Treatment of early HER2-positive breast cancer in trastuzumab era in everyday clinical practice: An overview after 10 years of its approval

Introduction: The addition of Trastuzumab(T) to chemotherapy (CT) revolutionized HER2-positive breast cancer(BC) and changed its natural history. We reviewed the efficacy of T outside clinical trials in a cancer comprehensive center.

Methods: Ambiespective and descriptive study was conducted in Catalan Institute of Oncology (ICO-Barcelona). Estimates of progression-free survival (PFS) and overall survival (OS) were obtained with the Kaplan-Meier method and compared with LogRank test. The association of clinic-pathological variables and outcome was studied by χ2and Cox proportional hazard analysis.

Results: 430 consecutive early HER2-positive BC patients (pts) were treated with adjuvant/neoadjuvant T and CT from Jan 2005 to Dec 2012. Pt basal characteristics are reported in Table 1. Neoadjuvant treatment was administrated in 230pts (54%) and in 200 (46%) in adjuvancy. Pathological complete response (pCR) in breast and nodes (ypT0/isypN0) was achieved in 48% of pts, with higher rates in hormone receptor (HR)-negative pts (62 vs 37% p=0.0005). Median duration of T: 10.6 months (m). 28%pts treated with neoadjuvant T+CT who achieved a pCR did not receive adjuvant T. Treatment discontinuation: 38pts (8.8%): 27pts due to cardiac toxicity and 4 relapsed during adjuvant T. In 87%pts, neoadjuvant CT was based on anthracyclines(A) and taxanes. Adjuvant CT: A and taxanes in 57.4%; 14%pts FAC, 15.4% A-CMF and 12% TCH. At a median follow-up of 70m (3-135), 44pts (10.4%) had relapsed: 33pts with distant M1, 9pts with only loco-regional disease and 2pts contralateral HER2-positive BC. M1 location: 46% visceral, 34% bone/lymph nodes and 20% in central nervous system (CNS). PFS was 23.4m(0-88); median OS was not reached; estimated 10 years-OS was 86.5%. Pts treated with A and taxanes had a significantly better OS compared to those treated with other CT (113 vs 98m, p= 0.009). Kaplan-Meier curve showed numerically higher relapses at 10 years in HR-positive pts (83 vs 90% p=0.8). Pts with pCR had significantly better OS (113 vs 104m, p=0.006). Pts with CNS-metastases had a significantly worse OS (13 vs 26m,p=0,02) and those with HR-negative (49 vs 24m, p= 0.033).

Conclusion: In everyday clinical practice, recurrences after adjuvant/neoadjuvant trastuzumab in HER2-positive BC were less than described in the T-pivotals trials, with 10% of recurrences at a median of FU of 70m. In our series, estimated 10 years-OS was 86.5%. Pts treated with A and taxanes had a significantly better OS as well as those pts who achieved a pCR. On the contrary, pts with CNS M1 and those with HR-negative had worse prognosis.

Table 1Median age51.9y (27-83)Stage I/II/III106 (25%)/ 226 (52%)/ 97 (23%)HR Positive/ Negative249 (58%)/181 (42%)

Citation Format: Ortega A, Domenech M, Falo C, Gil M, Stradella A, Fernandez A, Morilla I, Villanueva R, Castany R, Vazquez S, Molina K, Bergamino M, Navarro V, Pernas S. Treatment of early HER2-positive breast cancer in trastuzumab era in everyday clinical practice: An overview after 10 years of its approval [abstract]. In: Proceedings of the 2016 San Antonio Breast Cancer Symposium; 2016 Dec 6-10; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2017;77(4 Suppl):Abstract nr P4-21-32.

Stem cell-like transcriptional reprogramming mediates metastatic resistance to mTOR inhibition

Inhibitors of the mechanistic target of rapamycin (mTOR) are currently used to treat advanced metastatic breast cancer. However, whether an aggressive phenotype is sustained through adaptation or resistance to mTOR inhibition remains unknown. Here, complementary studies in human tumors, cancer models and cell lines reveal transcriptional reprogramming that supports metastasis in response to mTOR inhibition. This cancer feature is driven by EVI1 and SOX9. EVI1 functionally cooperates with and positively regulates SOX9, and promotes the transcriptional upregulation of key mTOR pathway components (REHB and RAPTOR) and of lung metastasis mediators (FSCN1 and SPARC). The expression of EVI1 and SOX9 is associated with stem cell-like and metastasis signatures, and their depletion impairs the metastatic potential of breast cancer cells. These results establish the mechanistic link between resistance to mTOR inhibition and cancer metastatic potential, thus enhancing our understanding of mTOR targeting failure.

Preradiotherapy MR Imaging: A Prospective Pilot Study of the Usefulness of Performing an MR Examination Shortly before Radiation Therapy in Patients with Glioblastoma

BACKGROUND AND PURPOSE

Current protocols in patients with glioblastoma include performing an MR examination shortly after surgery and then 2-6 weeks after ending concomitant chemoradiotherapy. The assessment of this first postradiotherapy examination is challenging because the pseudoprogression phenomenon may appear. The aim of this study was to explore if performing an MR examination shortly before radiation therapy (preradiotherapy MR imaging) could improve the radiologic assessment of patients with glioblastoma.

MATERIALS AND METHODS

A preradiotherapy MR imaging examination was prospectively performed before the start of radiation therapy in 28 consecutive patients with glioblastoma who had undergone surgical resection. Tumor response to chemoradiotherapy was assessed twice: with the early postoperative MR examination as baseline and with the preradiotherapy MR imaging examination as baseline. In addition, tumor growth in the preradiotherapy MR imaging examination was evaluated, and its correlation with patient survival was assessed with Kaplan-Meier analysis and Cox regression.

RESULTS

Tumor progression after radiation therapy was found in 16 patients, corresponding to pseudoprogression in 7 of them (44%). Four assessments of pseudoprogression switched to partial response or stable disease when preradiotherapy MR imaging was the baseline examination, and the ratio of pseudoprogression was reduced to 25% (3 of 12). Significant differences in survival were found when patients were stratified according to the pattern of tumor growth on preradiotherapy MR imaging (median overall survival "no-growth," 837 days; "focal-growth," 582 days; "global-growth," 344 days; P = .001).

CONCLUSIONS

Performing a preradiotherapy MR imaging examination may improve the clinical management of patients with glioblastoma by reducing the ratio of pseudoprogression assessments and providing prognostic information.