Adjuvant Hypofractionated Whole Breast Irradiation (WBI) vs. Accelerated Partial Breast Irradiation (APBI) in Postmenopausal Women with Early Stage Breast Cancer: 5Years Update of the HYPAB Trial

Therapeutical strategies in breast cancer are continuously updating. Recent researches assessed the possibility of irradiating only the surgical bed in selected patients (Partial Breast Irradiation, PBI). In 2014 we designed a study to evaluate toxicity and cosmesis of APBI using Volumetric Modulated Arc Therapy-Rapid Arc compared with hypofractionated whole breast irradiation (WBI). We present here the 5-years updated data. HYPAB was a single-institution randomized trial that recruited 172 patients from 2015 to 2018. Patients underwent conserving surgery and were randomized to either adjuvant WBI (40.5Gy/15 fractions with simultaneous boost to 48 Gy to tumoral bed) or APBI (30Gy/5 fractions), both delivered with VMAT-RA technique. Clinical evaluation was performed during the first visit, once a week during radiotherapy and during follow up. Cosmesis was assessed using the Harvard Scale for Breast Cosmesis. At the time of the analysis 161 patients were eligible, 53% in the WBI and 47% in the APBI group, with a median follow-up of 67 months. Most common late skin toxicities were G1 fibrosis (32%) and oedema (28%) and were higher in the WBI group; no G3 toxicities were observed. Cosmesis was rated poor in only 6 cases. 147 patients had no evidence of disease at the last follow-up, and no patients died of the disease. Mature results confirm the safety and efficacy of APBI in selected early stage breast cancer patients. Late toxicity is improved in the APBI arm at the cost of a slight increase in local relapse. Further studies are ongoing to better elucidate the use of APBI as a de-escalation approach.

Definitive results of a prospective non-randomized phase 2 study on stereotactic body radiation therapy (sbrt) for medically inoperable lung and liver oligometastases from breast cancer

BACKGROUND AND PURPOSE

To report mature results for local control and survival in oligometastatic (OM) breast cancer patients treated with stereotactic body radiotherapy (SBRT) on lung and/or liver lesions in a phase II trial.

METHODS

This is a prospective non-randomized phase II trial (NCT02581670) which enrolled patients from 2015 to 2021. Eligibility criteria included: age > 18 years, ECOG 0-2, diagnosis of breast cancer, maximum of 4 lung/liver lesions (with a maximum diameter < 5 cm), metastatic disease confined to the lungs and liver or extrapulmonary or extrahepatic disease stable or responding to systemic therapy. The primary end-points were local control (LC) and treatment-related toxicities. The secondary end-points included overall survival (OS), distant metastasis-free survival (DMFS), time to next systemic therapy (TTNS), poly-progression free survival (PPFS).

RESULTS

The study included 64 patients with a total of 90 lesions treated with SBRT. LC at 1 and 2 years was 94.9 %, 91 % at 3 years. Median local control was not reached. Median OS was 16.5 months, OS at 1, 2 and 3 years was 87.5 %, 60.9 % and 51.9 %, respectively. Median DMFS was 8.3 months, DMFS at 1, 2 and 3 years was 38.1 %, 20.6 % and 16 % respectively. At univariate analysis, local response to SBRT was found to be statistically linked with better OS, DMFS and STFS.

CONCLUSION

SBRT is a safe and valid option in oligometastatic breast cancer patients, with very high rates of local control. An optimal selection of patients is likely needed to improve survival outcomes and reduce the rate of distant progression.

Radiotherapy of orbital metastases: a systematic review of management and treatment outcomes on behalf of palliative care study group of Italian association of radiotherapy and clinical oncology (AIRO)

OBJECTIVES

We search the current literature on data regarding the role of RT in OM treatment, focusing on the improvement of symptoms and patient quality of life.

METHODS

This systematic review followed the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) recommendations.

RESULTS

From 340 citations, 60 papers were finally selected: 45 case reports and 15 case series. The case reports accounted for 47 patients. In 37/39 cases (95%), EBRT was done. Patients were mainly treated with 3DCRT, IMRT, and with SBRT. The most used RT regimens were 30 Gy in 10 fractions (23%) and 20-25 Gy in 5 fx (13%). No sever toxicity was reported. A median LC of 11 months (range 1-54 months) and a median OS of 12 months (range 1-54 months) were registered. Among the case series, a total of 457 patients were examined, 227 of whom underwent RT. The main used techniques were 3DCRT, CK, GK, SBRT, and BRT. RT doses could vary from 30 Gy/10 fractions to 60 Gy/30 fractions, 50 Gy/5 fractions, or 16.5-21 Gy in single fraction. No toxicity above G2 was reported. ORR could vary between 75 and 100%. Only two study provided information on response duration: a mean LC time of 22.8 months and a mean time to local progression of 5 months (range: 3-7). Regarding OS, the data were heterogeneous, ranging between 1 and 54 months.

CONCLUSIONS

RT for OM seems to be a safe and feasible option. More information on the RT ideal techniques and dose are still needed.

ADVANCES IN KNOWLEDGE

This paper tried to sum up the few and fragmented data on the use of radiotherapy for orbital metastases: the possible option ranged from 3D- and 2D-CRT to SBRT, CK, and GK, with different possible fractionations (30Gy in 10 fractions, 60 Gy/30 fractions, 20-50 Gy/5 fractions, or 16.5-21 Gy in single fraction). Regardless of the chosen approach, almost all treated patients experienced a benefit after RT in terms of OM-related symptom intensity reduction and a good acute and late toxicity profile.

Stereotactic radiation therapy for oligometastatic esophagogastric adenocarcinoma: outcome and prognostic factors

OBJECTIVE

The aim of this study was to evaluate clinical results and prognostic factors in a cohort of patient with oligometastatic esophagogastric adenocarcinoma treated with stereotactic radiation therapy (SRT).

METHODS

This retrospective study included patients affected by 1-3 metastases treated with SRT from 2013 to 2021. Local control (LC), overall survival (OS), progression-free survival (PFS), time to polymetastatic dissemination (TTPD) and time to systemic therapy change/initiation (TTS) were evaluated.

RESULTS

Between 2013 and 2021, 55 patients were treated with SRT on 80 oligometastatic sites. Median follow-up was 20 months. Nine patients had local progression. 1 and 3 years LC was respectively 92 and 78%. 41 patients experienced further distant disease progression, median PFS was 9.6 months, 1 and 3 years PFS was respectively 40 and 15%. 34 patients died, median OS was 26.6 months, 1 and 3 years OS was respectively 78 and 40%. During follow-up, 24 patients changed or initiated a new systemic therapy; median TTS time was 9 months. 27 patients experienced poliprogression, 44% after 1 year and 52% after 3 years. Median TTPD was 8 months. The best local response (LR), tyming of metastases and PS were related with prolonged PFS on multivariate analysis. LR was correlated with OS at multivariate analysis.

CONCLUSION

SRT represents a valid treatment for oligometastatic esophagogastric adenocarcinoma. CR correlated with PFS and OS, while metachronous metastasis and a good PS correlated with a better PFS.

ADVANCES IN KNOWLEDGE

In selected gastroesopagheal oligometastatic patients, SRT can prolong OS Local response to SRT, metachronous timing of metastases and better PS improve PFS.Local response correlates with OS.

Reirradiation on spine metastases: an Italian survey on behalf of palliative care and reirradiation study groups of Italian association of radiotherapy and clinical oncology (AIRO)

AIM

This survey derived from the collaboration between the Palliative Care and Reirradiation Study Groups of the Italian Association of Radiotherapy and Clinical Oncology (AIRO). Its aim was to obtain a real "snapshot" on the treatments of spinal metastases, focusing on reirradiation, among radiation oncologists in Italy.

METHODS

The survey was elaborated on SurveyMonkey's online interface and was sent via e-mail to all Radiation Oncologists of AIRO that were invited to anonymously fill in the electronic form within 60 days. The questionnaire was prepared by the AIRO "Palliative care" and "Reirradiation" Study Groups and it consisted of 36 questions, 19 single-choice questions, 10 multiple-choice questions and 6 open questions. The data were analyzed and represented with tables and graphs.

RESULTS

The survey shows that palliative radiotherapy remains a field of interest for most ROs in the Italian centers. 3D Conventional Radiation Therapy (3DCRT) alone or in combination with other techniques is the primary choice for patients with a life expectancy of less than 6 months. For patients with a life expectancy of more than six months, there is an increased use of new technologies, such as Volumetric Modulated Arc Therapy (VMAT). Factors considered for retreatment are time between first and second treatment, dose delivered to spine metastasis and spinal cord in the first treatment, vertebral stability, symptoms, and/or performance status. The most feared complication are myelopathy followed by vertebral fracture and local recurrence. This explain an increasing focus on patient selection and the use of high technology in the treatment of metastatic patients.

CONCLUSION

Stereotactic body radiotherapy (SBRT) and image-guided radiotherapy allow the administration of ablative RT doses while sparing the constraints of healthy tissue in spinal metastases. However, there is still an unclear and heterogeneous reality in the reirradiation of spinal metastases. A national registry with the aim of clarifying the most controversial aspects of vertebral metastasis retreatments will enable better management of these patients and design more targeted study designs.

Prognostic Score in Radiotherapy Practice for Palliative Treatments (PROPHET) Study for Bone Metastases: An Investigation Into the Clinical Effect on Treatment Prescription

Purpose

Bone metastases frequently occur during malignant disease. Palliative radiation therapy (PRT) is a crucial part of palliative care because it can relieve pain and improve patients' quality of life. Often, a clinician's survival estimation is too optimistic. Prognostic scores (PSs) can help clinicians tailor PRT indications to avoid over- or undertreatment. Although the PS is supposed to aid radiation oncologists (ROs) in palliative-care scenarios, it is unclear what type of support, and to what extent, could impact daily clinical practice.

Methods and Materials

A national-based investigation of the prescriptive decisions on simulated clinical cases was performed in Italy. Nine clinical cases from real-world clinical practice were selected for this study. Each case description contained complete information regarding the parameters defining the prognosis class according to the PS (in particular, the Mizumoto Prognostic Score, a validated PS available in literature and already applied in some clinical trials). Each case description contained complete information regarding the parameters defining the prognosis class according to the PS. ROs were interviewed through questionnaires, each comprising the same 3 questions per clinical case, asking (1) the prescription after detailing the clinical case features but not the PS prognostic class definition; (2) whether the RO wanted to change the prescription once the PS prognostic class definition was revealed; and (3) in case of a change of the prescription, a new prescriptive option. Three RO categories were defined: dedicated to PRT (RO-d), nondedicated to PRT (RO-nd), and resident in training (IT). Interviewed ROs were distributed among different regions of the country.

Results

Conversion rates, agreements, and prescription trends were investigated. The PS determined a statistically significant 11.12% of prescription conversion among ROs. The conversion was higher for the residents and significantly higher for worse prognostic scenario subgroups, respectively. The PS improved prescriptive agreement among ROs (particularly for worse-prognostic-scenario subgroups). Moreover, PS significantly increased standard prescriptive approaches (particularly for worse-clinical-case presentations).

Conclusions

To the best of our knowledge, the PROPHET study is the first to directly evaluate the potential clinical consequences of the regular application of any PS. According to the Prophet study, a prognostic score should be integrated into the clinical practice of palliative radiation therapy for bone metastasis and training programs in radiation oncology.

Stereotactic Body Radiation Therapy for Lung and Liver Oligometastases from Breast Cancer: Toxicity Data of a Prospective Non-Randomized Phase II Trial

AIMS

We report the mature toxicity data of a phase II non-randomized trial on the use of SBRT for lung and liver oligometastases.

METHODS

Oligometastatic patients from breast cancer were treated with SBRT for up to five lung and/or liver lesions. Inclusion criteria were: age > 18 years, ECOG 0-2, diagnosis of breast cancer, less than five lung/liver lesions (with a maximum diameter <5 cm), metastatic disease confined to the lungs and liver or extrapulmonary or extrahepatic disease stable or responding to systemic therapy. Various dose-fractionation schedules were used. Then, a 4D-CT scan and FDG-CTPET were acquired for simulation and fused for target definition.

RESULTS

From 2015 to 2021, 64 patients and a total of 90 lesions were irradiated. Treatment was well tolerated, with no G 3-4 toxicities. No grade ≥3 toxicities were registered and the coprimary endpoint of the study was met. Median follow-up was 19.4 months (range 2.6-73.1).

CONCLUSIONS

The co-primary endpoint of this phase II trial was met, showing excellent tolerability of SBRT for lung and liver oligometastatic in breast cancer patients. Until efficacy data will mature with longer follow-up, SBRT should be regarded as an opportunity for oligometastatic breast cancer patients.

Training and validation of a knowledge-based dose-volume histogram predictive model in the optimisation of intensity-modulated proton and volumetric modulated arc photon plans for pleural mesothelioma patients

BACKGROUND

To investigate the performance of a narrow-scope knowledge-based RapidPlan (RP) model for optimisation of intensity-modulated proton therapy (IMPT) and volumetric modulated arc therapy (VMAT) plans applied to patients with pleural mesothelioma. Second, estimate the potential benefit of IMPT versus VMAT for this class of patients.

METHODS

A cohort of 82 patients was retrospectively selected; 60 were used to "train" a dose-volume histogram predictive model; the remaining 22 provided independent validation. The performance of the RP models was benchmarked, comparing predicted versus achieved mean and near-to-maximum dose for all organs at risk (OARs) in the training set and by quantitative assessment of some dose-volume metrics in the comparison of the validation RP-based data versus the manually optimised training datasets. Treatment plans were designed for a prescription dose of 44 Gy in 22 fractions (proton doses account for a fixed relative biological effectiveness RBE = 1.1).

RESULTS

Training and validation RP-based plans resulted dosimetrically similar for both VMAT and IMPT groups, and the clinical planning aims were met for all structures. The IMPT plans outperformed the VMAT ones for all OARs for the contra-lateral and the mean and low dose regions for the ipsilateral OARs. Concerning the prediction performance of the RP models, the linear regression for the near-to-maximum dose resulted in D_achieved = 1.03D_predicted + 0.58 and D_achieved = 1.02D_predicted + 1.46 for VMAT and IMPT, respectively. For the mean dose it resulted: D_achieved = 0.99D_predicted + 0.34 and D_achieved = 1.05D_predicted + 0.27 respectively. In both cases, the linear correlation between prediction and achievement is granted with an angular coefficient deviating from unity for less than 5%. Concerning the dosimetric comparison between manual plans in the training cohort and RP-based plans in the validation cohort, no clinical differences were observed for the target volumes in both the VMAT and IMPT groups. Similar consistency was observed for the dose-volume metrics analysed for the OAR. This proves the possibility of achieving the same quality of plans with manual procedures (the training set) or with automated RP-based methods (the validation set).

CONCLUSION

Two models were trained and validated for VMAT and IMPT plans for pleural mesothelioma. The RP model performance resulted satisfactory as measured by the agreement between predicted and achieved (after full optimisation) dose-volume metrics. The IMPT plans outperformed the VMAT plans for all the OARs (with different intensities for contra- or ipsilateral structures). RP-based planning enabled the automation of part of the optimisation and the harmonisation of the dose-volume results between training and validation. The IMPT data showed a systematic significant dosimetric advantage over VMAT. In general, using an RP-based approach can simplify the optimisation workflow in these complex treatment indications without impacting the quality of plans.

Locally Advanced Non-Small Cell Lung Cancer: Clinical Outcome, Toxicity and Predictive Factors in Patients Treated with Hypofractionated Sequential or Exclusive Radiotherapy

Background: This study evaluated the outcome, toxicity and predictive factors in patients unfit for concurrent chemo-radiotherapy (CT-RT) treated with hypofractionated sequential CT-RT or exclusive radiotherapy (RT) for locally advanced non-small cell lung cancer (LA-NSCLC). Methods: We included patients affected by LA-NSCLC (stage IIA-IVA) treated with a total dose of 50–60 Gy in 20 fractions. The primary outcomes were local control (LC), distant metastasis-free survival (DMFS), progression-free survival (PFS) and overall survival (OS). Univariate analysis was used to correlate outcomes with prognostic factors. Results: Between 2011 and 2019, 210 patients were treated, 113 (53.8%) with sequential CT-RT and 97 (46.2%) with exclusive RT. After a median follow-up of 15.3 months, 74 patients (35.2%) had a local progression and 133 (63.3%) had a distant progression. The one-, two- and five-year LC were 73.6%, 55.3% and 47.9%, respectively. At the time of analysis, 167 patients (79.5%) died. The one-, two- and five-year OS were 64.7%, 36% and 20%, respectively. PTV volume correlated with PFS (p = 0.001) and LC (p = 0.005). Acute and late toxicity occurred in 82% and 26% of patients. Conclusions: Albeit with the known limitations of a retrospective and heterogeneous study, our work shows that hypofractionated sequential CT-RT or exclusive RT offer a good local control and toxicity profile and a promising survival rate in LA-NSCLC patients unfit for the concurrent CT-RT scheme.

Long term results of a phase II trial of hypofractionated adjuvant radiotherapy for early-stage breast cancer with volumetric modulated arc therapy and simultaneous integrated boost

PURPOSE

to report toxicity and cosmetic outcome with a median follow-up of 6 years of a phase II trial of hypofractionated radiotherapy with volumetric modulated arc therapy (VMAT) and simultaneous integrated boost (SIB) for early-stage breast cancer after conservative surgery.

MATERIALS AND METHODS

From August 2010 to September 2014, patients requiring adjuvant radiotherapy for early-stage breast cancer were treated according to a phase I-II protocol with SIB to 40.5 and 48 Gy to the breast and the boost region, respectively, with VMAT technique. The primary endpoint evaluated the treatment feasibility regarding adherence to required dose constraints for target, heart and lungs. Acute and late toxicity, local and distant control were secondary endpoints.

RESULTS

450 patients were included in the trial and analysed after a median follow-up of 6 years. Acute toxicity was already presented in a previous paper. Regarding late toxicity, 93% of patients had no skin alteration at five years, while 5.3% and 1.3% did record G1 and G2 residual toxicity, respectively. Cosmetic outcome was scored good or excellent in almost all cases (97.2%), fair only in 2.3% of patients. Residual tenderness in the irradiated breast was reported by 10% of patients. Cosmesis and breast pain improved during follow-up. Two cases of G2 pneumonitis and two cases of ischemic cardiopathy were registered during follow-up. Five cases presented local recurrence in the homolateral breast, four patients had a new primary cancer in the contralateral breast, while distant metastasis developed in 7 patients.

CONCLUSION

After more than six years, hypofractionated VMAT with SIB for adjuvant radiotherapy in early-stage breast cancer patients remains a safe and effective approach. Mature data on skin toxicity and cosmetic outcome are encouraging. However, longer follow-up is required to evaluate local control, cardiac toxicity and secondary carcinogenesis.

Knowing When to Use Stereotactic Ablative Radiation Therapy in Oligometastatic Cancer

Oligometastatic patients are a heterogeneous and yet not well-defined population. The actual definition identifies as oligometastatic, patients with 1-5 metastases in 1-3 different organs. However, only a proportion of these patients are "true" oligometastatic and therefore derive some kinds of benefit from local ablative approaches like stereotactic ablative radiation therapy (SABR). Since SABR is an easily accessible, effective and well-tolerated treatment, it is widely employed in the oligometastatic scenarios, without a particular focus on selection criteria. However, it should be crucial to identify predictive and prognostic features that could be clinically implemented. Therefore, we conducted this narrative review of the available literature to summarize all clinical, radiomic, genetic and epigenetic features found to be predictive of overall survival, progression-free survival or local control of oligometastatic patients treated with SABR.

Pro-Apoptotic Activity of Artichoke Leaf Extracts in Human HT-29 and RKO Colon Cancer Cells

(1) Background: Cynara cardunculus L. subsp. scolymus (L.) Hegi, popularly known as artichoke, is an herbaceous plant belonging to the Asteraceae family. Artichoke leaf extracts (ALEs) have been widely used in traditional medicine because of their hepatoprotective, cholagogic, hypoglycaemic, hypolipemic and antibacterial properties. ALEs are also recognized for their antioxidative and anti-inflammatory activities. In this study, we evaluated the cytotoxic, genotoxic, and apoptotic activities, as well as effect on cell growth of ALEs on human colon cancer HT-29 and RKO cells. HT-29 and RKO cells exhibit a different p53 status: RKO cells express the wild-type protein, whereas HT-29 cells express a p53-R273H contact mutant. (2) Methods: Four different ALEs were obtained by sequential extraction of dried artichoke leaves; ALEs were characterized for their content in chlorogenic acid, cynaropicrin, and caffeoylquinic acids. HT-29 and RKO cells were used for in vitro testing (i.e., cytotoxicity and genotoxicity assessment, cell cycle analysis, apoptosis induction). (3) Results: Two out of the four tested ALEs showed marked effects on cell vitality toward HT-29 and RKO tumour cells. The effect was accompanied by a genotoxic activity exerted at a non-cytotoxic concentrations, by a significant perturbation of cell cycle (i.e., with increase of cells in the sub-G₁ phase), and by the induction of apoptosis. (4) Conclusions: ALEs rich in cynaropicrin, caffeoylquinic acids, and chlorogenic acid showed to be capable of affecting HT-29 and RKO colon cancer cells by inducing favourable biological effects: cell cycle perturbation, activation of mitochondrial dependent pathway of apoptosis, and the induction of genotoxic effects probably mediated by the induction of apoptosis. Taken together, these results weigh in favour of a potential cancer chemotherapeutic activity of ALEs.

Enhancement of Parametric Effects in Polariton Waveguides Induced by Dipolar Interactions

Exciton-polaritons are hybrid light-matter excitations arising from the nonperturbative coupling of a photonic mode and an excitonic resonance. Behaving as interacting photons, they show optical third-order nonlinearities providing effects such as optical parametric oscillation or amplification. It has been suggested that polariton-polariton interactions can be greatly enhanced by inducing aligned electric dipoles in their excitonic part. However, direct evidence of a true particle-particle interaction, such as superfluidity or parametric scattering, is still missing. In this Letter, we demonstrate that dipolar interactions can be used to enhance parametric effects such as self-phase modulation in waveguide polaritons. By quantifying these optical nonlinearities, we provide a reliable experimental measurement of the direct dipolar enhancement of polariton-polariton interactions.

Household disinfectant exposure during the COVID-19 pandemic: a retrospective study of the data from an Italian poison control center

OBJECTIVE

Since the beginning of the COVID-19 pandemic it has been recommended that chemical disinfectants are used to protect surfaces. This study aimed to determine whether the number of exposure calls related to household disinfectants (HD) received between January 30, 2020 to May 18, 2020 varied from the same time period in the previous year.

MATERIALS AND METHODS

A retrospective review of the poison control center database from the Fondazione Universitario Policlinico Agostino Gemelli IRCCS, Rome, Italy, was conducted. Calls from Italian citizens, hospitals, and general practitioners received during the same time period in 2019 and 2020 were compared.

RESULTS

The center received 1972 exposure calls during the study period. A 5% increase in calls regarding exposure to HDs was noted from 2019 to 2020 (9.8% to 15.2%, p<0.001). The majority of enquiries regarded bleach-containing products, hand sanitizers, ethanol, and hydrogen peroxide. Most calls were received from patients in their homes (n, 259; prevalence, 86%; increase, 107%) and concerned accidental exposure (n, 280; prevalence, 93%; increase, 76%), while cases of intentional exposure decreased (n, 14; prevalence, 5%; decrease, 33%). The main route of exposure was ingestion (n, 170; prevalence, 57%; increase, 45%), but the highest increase was observed in inhalation cases (n, 82; prevalence, 27%; increase, 122%).

CONCLUSIONS

As the incidence of enquiries regarding products that can represent an important health hazard, when improperly used, increased in 2020 suggests that the COVID-19 public health messaging on the proper use of HDs should be improved.

Charlson comorbidity index and G8 in older old adult(≥80 years) hepatocellular carcinoma patients treated with stereotactic body radiotherapy

INTRODUCTION

Hepatocellular Carcinoma (HCC) is characterized, in Western countries, by higher incidence and mortality rates in the older adult population. In frail patients, limited therapeutic resources are available due to limited expected benefit concerning the risk of treatment-related toxicity. The aim of our study is to evaluate the role of Stereotactic Body Radiotherapy (SBRT) in the clinical management of older old adults (age ≥ 80 years) HCC patients and to identify predictors of efficacy and toxicity.

MATERIAL AND METHODS

Clinical and treatment-related data of older old adults HCC patients treated with SBRT at our institution were retrospectively reviewed. Statistical analysis was carried out to identify variables correlated with impaired outcome and toxicity.

RESULTS

Forty-two patients were included, accounting for 63 treated tumors. Median age was 85 (range 80-91) years. Median Charlson Comorbidity Index (CCI) and G8 scores were 10 (range 7-16) and 11 (range 8-14), respectively. SBRT was administered to a median BED10 of 103 Gy10. Median follow-up interval was 11 (range 3-40) months. Two years Local Control (LC), Progression-Free Survival (PFS), and Overall Survival (OS) were 93%, 31%, and 43%, respectively. Acute toxicity occurred in 28% (n = 13) of treatments. A G8 score > 10 was associated with improved survival (p = 0.045), while a CCI ≥10 was correlated with increased acute toxicity (p = 0.021).

CONCLUSIONS

SBRT is a safe and effective option in older old adults HCC patients. A comprehensive geriatric assessment (CGA) is advised before treatment decisions to select optimal candidates for SBRT.

Cytogenetic biomonitoring of road tunnel construction workers: buccal micronucleus cytome assay

Results

Road tunnel construction workers revealed higher frequencies of cells with genotoxic damage (i.e., MN and NBUD). MN and NBUD resulted to be Poisson distributed and counts of these genotoxicity biomarkers were then analysed by Poisson regression. The frequency ratio (FR) for MN was 1.31 (95% CI: 0.84-2.04), with an increase in the exposed subjects; this finding, though indicating a higher genotoxic risk in the exposed subjects, did not reach statistical significance. On the other hand, the FR for NBUD was 3.49 (95% CI: 1.86-6.56), with a statistically significant increased risk of chromosomal damage. Even the frequencies of binucleated cells (a marker of cell proliferation) and pyknotic cells (a cell death biomarker) were significantly higher in tunnel workers.

Introduction

Tunnel construction workers are exposed to complex mixtures of toxic agents, some of which are known to be genotoxic. The aim of this study was to evaluate the genotoxic risk in this occupational setting by comparing tunnel workers with a control group for frequencies of nuclear aberrations in oral exfoliated cells.

Methods

To evaluate the genotoxic effects of tunnel air pollutants, we conducted a cross-sectional, molecular epidemiological study (35 tunnel workers and 35 healthy controls) using the buccal micronucleus cytome assay. A questionnaire was administered to obtain information about demographic variables, lifestyle, dietary habits, anthropometric data, and occupational history. Buccal mucosa cells were collected by scraping the buccal mucosa with a small-headed toothbrush. Coded slides were examined blind by trained scorers for micronuclei (MN), nuclear buds (NBUD), and other nuclear abnormalities.

Conclusions

Our observations provide further knowledge and understanding of the occupational hazards of tunnel workers and confirm the complexity of effects (cytotoxic and genotoxic) probably induced by fumes and dust produced in underground operations.

Salvage radiotherapy for oligo-progressive malignant pleural mesothelioma

OBJECTIVES

No standard treatment option is available for patients with unresectable malignant pleural mesothelioma (MPM) progressing after upfront chemotherapy. We aimed to explore the role of focal radiotherapy (FRT) as a treatment modality for oligo-progressive MPM.

MATERIALS AND METHODS

In this retrospective study, consecutive patients pretreated with ≥1 lines of chemotherapy were included. Oligo-progressive MPM was defined as an unresectable disease with radiological progression at ≤3 sites according to a chest-abdominal contrast-enhanced computed tomography. Patients were treated with either stereotactic body radiotherapy (SBRT, ≥5 Gy per fraction) or hypo-fractionated radiotherapy (hypoRT, <5 Gy per fraction). Time to further systemic therapy (TFST) and local control (LC) after FRT were the primary endpoints. Biologically effective dose (BED) was calculated using three different alpha/beta models (1.5 Gy, 3 Gy and 10 Gy).

RESULTS

From April 2006 to March 2019, 37 patients were treated on 43 pleural lesions; 16/37 (43 %) had undergone upfront multimodality treatment (MMT) including surgery. FRT was given in 22/37 (59.5 %) after one line of chemotherapy. SBRT was delivered for 26/43 lesions (60.5 %), hypoRT for 17/43 (39.5 %). Median TFST was 6 months (95 % CI 4.9-7.1). LC at 6 months and 1 year was 84 % and 76 %, respectively. Median TFST was longer in patients treated after 1 vs >1 line of chemotherapy (9 vs 4 months, p = 0.001) and in patients pretreated with MMT (6 vs 3 months, p = 0.021). Six-month LC was better in patients treated with a BED > 100 using alpha/beta 1.5 and 3. No ≥ G3 acute or late toxicities were reported.

CONCLUSION

FRT was feasible in selected patients with oligo-progressive MPM, allowing delay of further systemic therapies, with no severe toxicity. FRT was more effective when performed at progression after one line of systemic therapy. Our results suggest a radio-resistant behavior of MPM.

Stereotactic body radiotherapy in hepatocellular carcinoma: patient selection and predictors of outcome and toxicity

INTRODUCTION

Stereotactic Body Radiotherapy (SBRT) emerged as a valuable option in early to advanced-stage Hepatocellular Carcinoma (HCC) as defined by Barcelona Clinic Liver Cancer (BCLC) system. The aim of our study is to evaluate SBRT in HCC patients and to identify predictors of outcome and toxicity.

MATERIALS AND METHODS

A retrospective review of HCC patients treated at our Institution between November 2011 and December 2018 was carried out. SBRT was delivered in 3-10 fractions to a median Biologically Effective Dose (BED¹⁰) of 103 Gy¹⁰.

RESULTS

SBRT was performed in 128 patients to 217 HCC localizations, accounting for 142 treatment courses. BCLC stage was A, B, C in, respectively, 40 (31%), 72 (56%) and 16 (13%) patients. Local Control (LC), Progression Free Survival (PFS) and Overall Survival (OS) at 2 years were, respectively: 78%, 15% and 58%. LC was influenced by BED10 > 120 Gy¹⁰ (Hazard Ratio, HR: 0.08, 95% CI 0.01-0.59; p = 0.013) and size ≥ 3 cm (HR: 2.71, 95% CI 1.10-6.66; p = 0.03). BCLC stage was correlated to PFS (median 14 vs 12 vs 5 months, p = 0.012). In BCLC stage A-B disease (n = 112), LC was associated with improved survival (median 30 months vs not reached, p = 0.036). Acute and late toxicity rate was 26% (n = 37) and 8% (n = 11). Patients with BCLC B-C stage disease showed increased acute toxicity (HR: 2.9, 95% CI 1.10-7.65; p = 0.032).

CONCLUSION

Delivery of ablative doses > 120 Gy¹⁰ and tumor size are determinants of LC. Prolonged PFS and improved OS can be obtained in BCLC A-B patients. Grade 3 liver dysfunction is infrequent.

Imbalance in the antioxidant defence system and pro-genotoxic status induced by high glucose concentrations: In vitro testing in human liver cells

It has been hypothesized that high glucose concentrations might contribute to the overall intracellular oxidative stress either by the direct generation of reactive oxygen species (ROS) or by altering the redox balance. Moreover, it has also been suggested that high glucose concentration can increase the susceptibility of DNA to genotoxic effects of xenobiotics. The aim of this approach was to test high glucose concentrations for pro-genotoxicity in human liver cells by setting up an in vitro model for hyperglycaemia. The experimental design included performing of tests on both human HepG2 tumour cells and HepaRG immortalized cells. Increased cell susceptibility to genotoxic xenobiotics was tested by challenging cell cultures with 4-nitroquinoline-N-oxide (4NQO) and evaluating the extent of primary DNA damage by comet assay. Moreover, we evaluated the relationship between glucose concentration and intracellular ROS, as well as the effects of glucose concentration on the induction of Nrf2-dependent genes such as Glutathione S-transferases, Heme‑oxygenase-1, and Glutathione peroxidase-4. To investigate the involvement of ROS in the induced pro-genotoxic activity, parallel experimental sets were set up by considering co-treatment of cells with the model mutagen 4NQO and the antioxidant, glutathione precursor N-acetyl-L-cysteine. High glucose concentrations caused a significant increase in the levels of primary DNA damage, with a pro-genotoxic condition closely related to the concentration of glucose in the culture medium when cells were exposed to 4NQO. High glucose concentrations also stimulated the production of ROS and down-regulated genes involved in contrasting of the effects of oxidative stress. In conclusion, in the presence of high concentrations of glucose, the cells are in unfavourable conditions for the maintenance of genome integrity.

OP0204 LUPUS COMPREHENSIVE DISEASE CONTROL IN SYSTEMIC LUPUS ERYTHEMATOSUS PATIENTS: APPLICATION OF A NEW INDEX

Background:

The main outcomes in SLE patients management are represented by the remission achievement and chronic damage prevention. Even though activity and damage are intimately connected, to date indices including both these outcomes are not available.

Objectives:

In the present study, we aimed at assessing the application of a new index, the Lupus comprehensive disease control (LupusCDC), including disease activity and chronic damage progression.

Methods:

We performed a longitudinal analysis, including SLE patients according to ACR 1997 criteria, followed-up in the period between January 2014 and December 2018, and with at least one visit per year. Disease activity was assessed by SLE Disease Activity Index 2000 (SLEDAI-2K) and three different remission levels were evaluated, as reported in Table 1 (1).

Table 1.

Remission levels considered in the study (1).

Remission levelDefinitionComplete Remission(CR)No clinical and serological activity (SLEDAI-2K=0) in corticosteroid-free and immunosuppressant-free patients (antimalarials allowed)Clinical remission off-corticosteroids(ClR-GCoff)Serological activity with clinical quiescent disease according to SLEDAI-2K in corticosteroid-free patients (stable immunosuppressive therapy and antimalarials allowed)clinical remission on-corticosteroids(ClR-GCon)Clinical quiescent disease according to SLEDAI-2K in patients on prednisone 1–5 mg/day (stable immunosuppressants and antimalarials allowed)

Chronic damage was registered according to SLICC damage index (SDI). All the patients were evaluated at baseline (T0) and every 12 months (T1, T2, T3, T4). At each time-point, we calculated the prevalence of LupusCDC, defined as remission achievement plus absence of chronic damage progression in the previous one year. We calculated this outcome including separately the different remission levels.

Results:

According with inclusion criteria, 172 SLE patients were evaluated in the present analysis [M/F 16/156, median age 49 years (IQR 16.7), median disease duration 180 months (IQR 156)]. At first assessment, we observed a mean±SD SDI value of 0.7±1.1. In details, 56 patients (32.5%) showed damage in at least one organ/system and the presence of damage was significantly associated with age (p<0.0001, r=0.3) and disease duration (p=0.0003, r=0.3). During the follow-up, we observed a significant increase in SDI values compared with T0 (T1: mean±DS 0.8±1.3, p<0.0001; T2: 0.8±1.4, p<0.0001; T3: 0.9±1.4 p=0.0001; T4: 1.0±1.5 p<0.0001).

In figure 1A and 1B we reported the proportion of patients achieving the different levels of remission and LupusCDC, respectively. In particular, the LupusCDC definition including CR was the most frequently detected in all time-points evaluated (T1: 18.0%; T2: 31.9%; T3: 27.9%; T4: 24.4%), with a significant difference at T2 [LupusCDC(CR)versusLupusCDC(ClR-GCoff), p=0.0002; LupusCDC(CR)versusLupusCDC(ClR-GCon) p=0.0002)], T3 [LupusCDC(CR)versusLupusCDC(ClR-GCoff), p=0.03; LupusCDC(CR)versusLupusCDC(ClR-GCon) p=0.006], T4 [LupusCDC(CR)versusLupusCDC(ClR-GCon), p=0.002]. No significant differences were found when comparing the prevalence of different remission levels and the prevalence of LupusCDC including the corresponding remission.

Conclusion:

In the present analysis we proposed for the first time a new index including disease activity and chronic damage, in order to evaluate the proportion of SLE patients reaching a comprehensive disease control. We found that CR is most frequently associated with the absence of damage progression.

References:

[1]Zen M et al. Ann Rheum Dis 2017.

Disclosure of Interests:

Fulvia Ceccarelli: None declared, Giulio Olivieri: None declared, Lorenzo Dominici: None declared, Alessandra Ida Celia: None declared, enrica cipriano: None declared, Cristina Garufi: None declared, Silvia Mancuso: None declared, Francesco Natalucci: None declared, Valeria Orefice: None declared, Carlo Perricone: None declared, Carmelo Pirone: None declared, viviana antonella pacucci: None declared, Francesca Morello: None declared, Simona Truglia: None declared, Francesca Miranda: None declared, Francesca Romana Spinelli Grant/research support from: Pfizer, Consultant of: Novartis, Gilead, Lilly, Sanofi, Celgene, Speakers bureau: Lilly, cristiano alessandri Grant/research support from: Pfizer, fabrizio conti Speakers bureau: BMS, Lilly, Abbvie, Pfizer, Sanofi

Cyclin-Dependent Kinase 4/6 Inhibitors Combined With Radiotherapy for Patients With Metastatic Breast Cancer

BACKGROUND

The cyclin-dependent kinase 4/6 inhibitors (CDK4/6i) represent the standard treatment for hormone receptor-positive, human epidermal growth factor receptor 2-negative metastatic breast cancer. Data about the balance between efficacy and toxicity of combined palliative radiotherapy (RT) and CDK4/6 inhibition are lacking.

PATIENTS AND METHODS

We undertook a review of 46 patients with metastatic breast cancer on systemic treatment with CDK4/6i who underwent 62 metastases-directed RT. Clinical, laboratory, and RT treatment planning data were collected. Statistical analyses included Student t test, paired sample t test, and logistic regression modeling.

RESULTS

Thirty patients (65.2%) received palbociclib, 15 (32.6%) received ribociclib, and one patient received abemaciclib (2.2%). Median total prescribed RT dose was 20 Gy (range, 8-63 Gy). Sites of RT were bone (n = 50; 80.7%), visceral (n = 7; 11.3%), or brain metastases (n = 3; 4.8%), as well as primary tumor of the breast (n = 2; 3.2%). Overall, the rates of grade 3 or higher adverse events (AEs) were 6.5%, 4.3%, 15.2%, and 23.9% before the start of RT, during RT, 2 and 6 weeks after RT completion, respectively. We found no correlation between dose distribution to organs at risk and the development of AEs. The local control rates for the entire cohort were 98% at 6 months and 90% at 12 months. Overall, pain relief (complete or partial) was experienced by 80% (24/30) of patients who initially reported pain at the treated metastatic site.

CONCLUSION

We observed a modest increase in the rates of grade 3 or higher AEs after combined RT and CDK4/6i, with maintained efficacy of concomitant RT.

Impact of metastases directed radiation therapy on CDK4/6 inhibitors dose reduction and treatment discontinuation for metastatic HR+/HER2- breast cancer (MBC)

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Background: Cyclin-Dependent Kinase 4/6 inhibitors (CDK4/6i) represent the standard I-II line for hormonal receptors positive/human epidermal growth factor receptor 2 negative metastatic breast cancer (MBC) patients. Metastases directed radiotherapy (RT) for these patients is commonly used with palliative or radical schedules during systemic treatment. Although encouraging preliminary results were published, there is still a lack of robust data on the safety concerning RT during CDK4/6i treatment. Methods: we analyzed at Our Institution 85 consecutive patients treated in I (n=47) and II line (n=38) for MBC with CDK4/6i between April 2017 and September 2019 (22 ribociclib, 63 palbociclib). Overall, 25 (29.4%) patients received metastases directed RT during CDK4/6i treatment, including 14 concomitant (16.5%) and 11 sequential (12.9%). Estimated CDK4/6i half-life is 26 and 30 hours for palbociclib and ribociclib, respectively. Five half-lives are required to reduce drug concentration by 95-97%; thus, we also analyzed CDK4/6i treatment as non-concomitant or sequential to RT. Main endpoints of our analysis were impact of RT on CDK4/6i dose reduction and discontinuation, overall adverse events rate (any grade and grade ≥2), and neutropenia grade ≥2 as per CTCAE scale version 5.0. Results: at a median follow up of 12 months (range 3-29), we observed a CDK4/6i dose reduction in 35 patients (41.2%) and 5 patients (5.9%) discontinued treatment due to adverse events; 82 patients (96.5%) experienced any grade of toxicity, 72 (84.7%) a grade ≥2 and 70 patients (82.4%) neutropenia grade ≥2. We did not observe significant difference in terms of CDK4/6i dose reduction or discontinuation, any grade or grade ≥2 toxicity, neutropenia grade ≥2 in the comparison between patients receiving RT versus no RT and between patients receiving concomitant RT versus sequential RT versus no-RT (Table). Conclusions: our results showed that the prescription of a metastases directed RT during treatment with a CDK4/6i as I-II line for MBC did not significantly impact on dose reduction or discontinuation caused by an exceeding in adverse event rate. Although these promising results, caution should be used and cooperative initiatives strongly encouraged. [Table: see text]

Analysis of skin dose distribution for the prediction of severe radiation dermatitis in head and neck squamous cell carcinoma patients treated with concurrent chemo-radiotherapy

BACKGROUND

We investigated whether the pattern of intensity-modulated radiotherapy (IMRT) dose distribution to the skin can be correlated with the development of G3/G4 radiation dermatitis (RD).

METHODS

A frequency-matched cohort analysis was perfomed on patients treated with IMRT and concurrent cisplatin or cetuximab. Risk ratios were obtained by fitting Poisson regression models.

RESULTS

The incidence of G3/G4 RD was 41.1% in 90 patients included (50% vs 36.6% in the cetuximab and cisplatin cohorts, respectively). In multivariate analysis, PS ≥ 1 and weight loss at RT completion >10 kg were the only factors that retained significance. The best dosimetric predictive accuracy was provided by 19.9 cc and 5.8 cc of skin ring 2 mm V50 and V60, respectively (AUC: 0.61 for both).

CONCLUSION

Along with clinical factors, the pattern of dose distribution to a ring structure localized 2 mm below the patient's surface may help predict the development of severe RD.

Two-dimensional hybrid perovskites sustaining strong polariton interactions at room temperature

Polaritonic devices exploit the coherent coupling between excitonic and photonic degrees of freedom to perform highly nonlinear operations with low input powers. Most of the current results exploit excitons in epitaxially grown quantum wells and require low-temperature operation, while viable alternatives have yet to be found at room temperature. We show that large single-crystal flakes of two-dimensional layered perovskite are able to sustain strong polariton nonlinearities at room temperature without the need to be embedded in an optical cavity formed by highly reflecting mirrors. In particular, exciton-exciton interaction energies are shown to be spin dependent, remarkably similar to the ones known for inorganic quantum wells at cryogenic temperatures, and more than one order of magnitude larger than alternative room temperature polariton devices reported so far. Because of their easy fabrication, large dipolar oscillator strengths, and strong nonlinearities, these materials pave the way for realization of polariton devices at room temperature.

Abstract GS6-01: Surgical treatment after neoadjuvant systemic therapy in young women with breast cancer: Results from a prospective cohort study

Background

Young women are more likely than older women to present with higher stage breast cancer (BC) and may benefit to a greater extent from downstaging with neoadjuvant systemic treatment (NST). Young age is also associated with greater likelihood of pathologic complete response (pCR). Using a large prospective cohort of young women with BC, we investigated response to neoadjuvant therapy, eligibility for breast conserving surgery (BCS) pre- and post-NST, and surgical treatment.

Methods

The Young Women's Breast Cancer Study (YWS) is a multi-center cohort of women diagnosed with BC at age ≤40, that enrolled 1302 patients from 2006 to 2016. Disease characteristics and treatment information were obtained through medical record and central pathology review. Surgical recommendation before and after NST, conversion from BCS borderline/ineligible to BCS eligible, surgery, documented reasons for choosing mastectomy (MTX) among BCS eligible women, and final pathologic response were independently reviewed.

Results

Among 1302 women enrolled in YWS, 801 (62%) presented with unilateral stage I-III breast cancer and 317(40%) received NST. Median age was 36 years old (22-40). Pre-NST, 85/317 (27%) were BCS eligible, 49 (15%) were borderline, and 169 (53%) were not eligible (16 inflammatory breast cancer (IBC), 88 large tumor size /cosmetic, 48 diffuse calcifications, and 83 multicentricity). Among the 218 patients who were BCS ineligible/borderline pre-NST, 82 (38%) became eligible for BCS after NST. 4 patients who were BCS eligible pre-NST became ineligible. Of all patients eligible for BCS post-NST (n=163), 80 (49%) attempted BCS, 74 (93%) of whom were successful, and 83 (51%) chose MTX. Reasons for choosing MTX included: patient preference (38/83 (46%)), BRCA or TP53 mutation (31 (37%)), family history (3 (4%)), unknown (11 (13%)). On final pathology, 75 (24%) patients had pCR. Among patients who achieved a pCR, 48 (64%) underwent MTX, fewer than half (21/48 (44%)) were for anatomic indications (IBC, large tumor at diagnosis, diffuse calcifications, multicentric disease).

Conclusion

While NST doubled the proportion of young women eligible for BCS, nearly half chose MTX regardless of response to NST, mostly for personal preference or high-risk preventative reasons. These data highlight that surgical decision making among young women with breast cancer is often driven by factors beyond extent of disease and clinical response to therapy.

Table 1.Clinical-pathologic characteristicsCharacteristicsNumber%Pre NST surgical recommendation  BCS eligible8526.8Borderline4915.5BCS ineligible16953.3Unknown144.4Clinical Response  Complete20263.7Partial9229.0Stable30.9Progressing72.2Unknown134.1Pathologic Response  pCR (No invasive or DCIS)7524No pCR24276Post NST Surgical recommendation  BCS eligible16351.4BCS ineligible14445.4Unknown103.2Attempted surgery  BCS8025.2MTX23674.1Unknown20.6Final Surgery  BCS7423.3MTX24176unknown20.6

Citation Format: Kim HJ, Dominici L, Rosenberg S, Pak LM, Poorvu PD, Ruddy K, Tamimi R, Schapira L, Come S, Peppercorn J, Borges V, Warner E, Vardeh H, Collins L, King T, Partridge A. Surgical treatment after neoadjuvant systemic therapy in young women with breast cancer: Results from a prospective cohort study [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 GS6-01.

Stereotactic body radiation therapy (SBRT) on renal cell carcinoma, an overview of technical aspects, biological rationale and current literature

BACKGROUND

Stereotactic body radiotherapy (SBRT) is characterized by the delivery of high doses of ionizing radiation in few fractions. It is highly effective in achieving local control, and, due to the high biological effective dose administered, it seems to overcome the radioresistance of renal cell carcinoma (RCC). Thus, SBRT could constitute a treatment option for the management of localized RCC in patients who are not surgical candidates. In this paper, we report an overview about data from the current evidence about SBRT in patients affected by localized RCC.

MATERIALS AND METHODS

A non-systematic review was performed, including data from both retrospective and prospective studies focusing on the use of SBRT for localized RCC and its biological rationale. Furthermore, ongoing trials on this issue are reported.

CONCLUSION

Currently, SBRT might be considered a treatment alternative in inoperable patients affected by primary RCC. Currently, dose-escalation to 48 Gy in 3-4 fractions are effective and well tolerated. Emerging role of immune therapies in RCC patients warrant further studies to explore interactions between SBRT and immune response.

Enhancement of Soft Tissue Sarcoma Cell Radiosensitivity by Poly(ADP-ribose) Polymerase-1 Inhibitors

Soft tissue sarcomas (STS) are aggressive tumors with a poor prognosis. Poly(ADP-ribose) polymerase (PARP)-1 inhibitors (PARPi) enhance the cytotoxic effects of radiation. In this study, we evaluated the effect of PARPi on survival and DNA damage of irradiated STS cells. For clonogenic assays, STS cell lines were irradiated with or without olaparib, iniparib or veliparib pretreatment. The effect of PARP inhibition on γ-H2AX and Rad51 foci formation, on PARP-1, phospho-ERK and cleaved caspase-3 protein expression and on cell cycle progression was evaluated on irradiated rhabdomyosarcoma cells pretreated with olaparib. The results from this work showed that PARPi induced significant radiosensitization in STS cells. Rhabdomyosarcoma cells showed the highest increase in radiosensitivity, with a radiosensitization enhancement ratio at 50% survival (ER50) of 3.41 with veliparib. All PARPi exerted a synergistic effect when combined with radiation. Fibrosarcoma cells showed an ER50 of 2.29 with olaparib. Leiomyosarcoma and liposarcoma cells showed their highest ER50 with veliparib (1.71 and 1.84, respectively). In rhabdomyosarcoma, olaparib enhanced the formation of radiation-induced γ-H2AX/Rad51 foci and PARP-1 cleavage, induced slightly increased expression of cleaved caspase-3 and reduced phospho-ERK expression. Moreover, the combination of olaparib and radiation resulted in a significantly enhanced cell cycle arrest in the G₂/M phase compared to the two treatments alone. In conclusion, we have shown that PARPi are potent radiosensitizers of human STS cells. These results support the pursuit of further investigations into the effects of PARPi combined with radiation on STS.

hERG1 channel expression associates with molecular subtypes and prognosis in breast cancer

Background

Breast cancer (BC) is the most frequent malignancy among females worldwide. Despite several efforts and improvements in early diagnosis and treatment, there are still tumors characterized by an aggressive behavior due to unfavorable biology, thus quite difficult to treat. In this view, searching for novel potential biomarkers is mandatory. Among them, in the recent years data have been gathered addressing ion channel as important players in oncology.

Methods

A retrospective pilot study was performed on 40 BC samples by means of immunohistochemistry in order to evaluate hERG1 potassium channels expression in BC.

Results

We provide evidence that hERG1 is expressed in all the BC samples analyzed. hERG1 expression was significantly associated with molecular subtype with the highest expression in Luminal A and the lowest in basal-like tumors (p = 0.001), tumor grading (the highest hERG1 expression in well-moderate differentiated tumors, p = 0.020), estrogen receptors (high hERG1 expression in ER-positive samples, p = 0.008) and Ki67 proliferative index (high hERG1 scoring in samples with low proliferative index, p = 0.038). Also, a p value close to significance was noticed for the association between hERG1 and HER2 expression (p = 0.079). At the survival analysis, patients with high hERG1 expression turned out to have a longer progression-free survival, although statistical significance was not reached (p = 0.195). The same trend was observed analyzing local relapse free-survival (LRFS) and metastases-free survival (MFS): patients with higher hERG1 scoring had longer LRFS and MFS (p = 0.124 and p = 0.071, respectively).

Conclusions

The results of this pilot study provide the first evidence that the hERG1 protein is expressed in primary BC, and its expression associates with molecular subtype. hERG1 apparently behaves as a protective factor, since it contributes to identify a subset of patients with better outcome. Overall, these data suggest that hERG1 might be an additional tool for the management of BC, nevertheless further investigations are warranted to better clarify hERG1 role and clinical usefulness in BC.

Abstract P6-15-11: Weekly paclitaxel, pertuzumab and trastuzumab (TPH) neoadjuvant therapy for HER2 positive inflammatory breast cancer

Background: Inflammatory breast cancer (IBC) is inoperable at presentation, thus neoadjuvant systemic therapy (NAS) is the primary treatment for this aggressive disease. Due to its rarity, patients (pts) with IBC are incorporated into NAS clinical trials for locally advanced breast cancer, making it difficult to extrapolate efficacy specifically for pts with IBC. A commonly used regimen for the treatment of HER2+ IBC includes docetaxel, carboplatin, pertuzumab (P) and trastuzumab (H), yet only 6% of pts enrolled in the clinical trial for this regimen had IBC. We sought to examine the efficacy of maximizing anti-HER2 therapy combined with minimal chemotherapy using the THP regimen specifically for pts with HER2+ IBC.

Methods: Pts with newly diagnosed HER2+ IBC received NAS with 16 weeks (wks) of paclitaxel (T) 80mg/m2/wk, H (2mg/kg/wk) and P(420mg/kg/3wk) followed by modified radical mastectomy (MRM) on a phase II prospective study. All pts had 2 research breast biopsies (rbx) for correlative assays prior to and 1 wk after the P (840mg/kg) and H (4 mg/kg) loading dose. Pts who achieved a pCR (pathologic complete response) could opt out of adjuvant doxorubicin (A) 60 mg/m2 + cyclophosphamide (C) 600mg/m2 x 4; pts with residual disease received AC. All pts received post-mastectomy radiation and maintenance P (420mg) + H (6mg/kg) every 3 wks x 12. Adjuvant endocrine therapy was given per standard of care. Primary objective was pCR rate in the breast and axillary lymph nodes. Residual Cancer Burden (RCB) was assessed. Based upon a Simon two-stage design, this regimen would be declared worthy of further study if &gt;7/27 pCR were observed (15% vs 40%; target α=0.039 power=0.90). The study was closed after 23/27 pts were enrolled due to slow accrual.

Results: 20 pts were enrolled as of 12/2016, 18 completed NAS and MRM. All but 1 had stage III disease at presentation. 1 pt was lost to follow-up; 1 developed CNS metastasis during NAS and did not undergo MRM. The mean age was 49 years, 10 pts had ER/PR negative disease. 15 pts completed 16 wks of T, 4 had 15 wks and 1 had 13 wks. During NAS, there was no grade (gd) 4 toxicity; 6 episodes of gd 3 toxicity (2 related to treatment-diarrhea); and no gd 3 cardiac events. In the intent to treat analysis, 10/20 pts achieved pCR (50%; 90% CI 30-70%) and 6 had RCB-1 (30%). 5 pts with RCB-1 response had &lt;5 mm residual disease; 1 had lymph node involvement. Of those proceeding to MRM, pCR rate was 56% (10/18). 6/10 opted out of AC. Treatment and follow-up for clinical outcomes continue. Biologic correlatives investigating genomic profiling and patterns of HER2 resistance are being performed on rbx, residual disease and cfDNA.

Conclusion: THP x 16wks is tolerable and effective NAS for HER2+ IBC, resulting in a high pCR rate with minimal toxicity. This study of NAS explored the benefit of maximizing HER2-directed therapy and minimizing chemotherapy and its associated toxicity. It has achieved its primary endpoint and will be used as the backbone NAS for HER2+ IBC, with future studies building upon this regimen. The result of this trial supports the benefit of clinical trials designed specifically for pts with IBC. Clinical trial information: NCT01796197.

Citation Format: Overmoyer B, Regan M, Hu J, Nakhlis F, Dominici L, Lin NU, Freedman R, Morganstern DE, Partridge AH, Schlosnagle EJ, Hirshfield-Bartek J, Bellon J, Morikawa A, Harrison BT, Winer E. Weekly paclitaxel, pertuzumab and trastuzumab (TPH) neoadjuvant therapy for HER2 positive inflammatory breast cancer [abstract]. In: Proceedings of the 2017 San Antonio Breast Cancer Symposium; 2017 Dec 5-9; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2018;78(4 Suppl):Abstract nr P6-15-11.

No evidence of DNA damage by co-exposure to extremely low frequency magnetic fields and aluminum on neuroblastoma cell lines

Whether exposure to 50-60Hz extremely low frequency magnetic fields (ELF-MF) exerts neurotoxic effects is a debated issue. Analogously, the potential role of Aluminum (Al) in neurodegeneration is a matter of controversial debate. As all living organisms are exposed to ELF-MF and/or Al daily, we found investigating the early effects of co-exposure to ELF-MF and Al in SH-SY5Y and SK-N-BE-2 human neuroblastoma (NB) cells intriguing. SH-SY5Y5 and SK-N-BE-2 cells underwent exposure to 50Hz ELF-MF (0.01, 0.1 or 1mT) or AlCl₃ (4 or 40μM) or co-exposure to 50Hz ELF-MF and AlCl₃ for 1h continuously or 5h intermittently. The effects of the treatment were evaluated in terms of DNA damage, redox status changes and Hsp70 expression. The DNA damage was assessed by Comet assay; the cellular redox status was investigated by measuring the amount of reduced glutathione (GSH) and glutathione disulfide (GSSG) while the inducible Hsp70 expression was evaluated by western blot analysis and real-time RT-PCR. Neither exposure to ELF-MF or AlCl₃ alone induced DNA damage, changes in GSH/GSSG ratio or variations in Hsp70 expression with respect to the controls in both NB cell lines. Similarly, co-exposure to ELF-MF and AlCl₃ did not have any synergic toxic effects. The results of this in vitro study, which deals with the effects of co-exposure to 50Hz MF and Aluminum, seem to exclude that short-term exposure to ELF-MF in combination with Al can have harmful effects on human SH-SY5Y and SK-N-BE-2 cells.

Evaluation of cytotoxicity, genotoxicity, and apoptosis of wastewater before and after disinfection with performic acid

Disinfection with performic acid (PFA) represents an emerging technology in wastewater treatment. Many recent studies indicate its effectiveness and suitability as a disinfectant for different applications; several have demonstrated its reliability as an alternative to chlorine for disinfecting secondary effluents from urban wastewater treatment plants (WWTPs). Some disinfection technologies, in relation to their oxidative power, lead to the formation of disinfection by-products (DBPs), some of which are of concern for their toxic and carcinogenic potential. The aim of this study was to investigate potential genotoxic, cytotoxic, and mutagenic effects of this disinfection agent on treated secondary effluent coming from a municipal WWTP. A strategy with multiple short-term tests and different target cells (bacterial, plant, and mammalian) was adopted to explore a relatively wide range of potential genotoxic events. The Ames test (point mutation in Salmonella), the micronucleus (chromosomal damage) and Comet tests (primary DNA damage) on human hepatic cells (HepG2) were conducted to detect mutagenicity and chromosomal DNA alterations. DNA fragmentation and mitochondrial potential assays were conducted to evaluate apoptosis in the same kinds of cells. Mutagenic and clastogenic effect potentials were evaluated by examining micronucleus formation in Allium cepa root cells. In all the in vitro tests, carried out on both disinfected and non-disinfected effluents, negative results were always obtained for mutagenic and genotoxic effects. In the Allium cepa tests, however, some non-concentrated wastewater samples after PFA treatment induced a slight increase in micronucleus frequencies in root cells, but not in a dose-related manner. In conclusion, PFA applied for disinfection to a secondary effluent from a municipal wastewater treatment plant did not contribute to the release of genotoxic or mutagenic compounds. Further studies are required to establish to which extent these findings can be generalized to support PFA for other disinfection applications.

Multimodality treatment of synovialsarcoma: A single institution experience

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Background: Synovialsarcoma (SS) is a relatively rare cancer, accounting for 8% of all Soft-Tissue Sarcomas (STS). Identifying prognostic factors could allow to improve treatment strategy for this disease. Methods: Data of 52 patients treated at University of Florence between 1999 and 2016 were retrospectively analysed. Patients and treatment features (Table 1) were correlated with outcome. Results: At a median follow-up of 8.4 years, 9 deaths, 3 local recurrences (LR) and 19 distant metastases (DM) have occurred (17,3%, 5,8% and 36,5%, respectively). Survival Kaplan-Meier analysis showed that Overall survival (OS), Local recurrence disease free survival (DFS-LR) and Distant metastases disease free survival (DFS-DM) were 74,5%, 90% and 59,3%, respectively. Size>10 cm was the only significant predictor of OS (p=0,004). Age>40, size>10 cm and G3 significantly influenced DFS-DM (p=0,043, p=0,002 and p=0,002, respectively). Cox univariate regression analysis confirmed the impact of size on OS (HR 5.8, 95% CI 1.37-24.43, p=0,017). Size (HR 5.06, 95% CI 1.73-14.79, p=0.003) and Grade (7.19, 95% CI 1.65-31.37, p=0.009) influenced DFS-DM. G3 was the only independent prognostic factor associated with DFS-DM. Conclusions: These data confirm that age, size and grade significantly influence outcome in patients affected by SS. Further studies are needed in order to develop tailored treatment strategies in this setting. [Table: see text]

Management of liposarcoma: A single institutional analysis

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Background: Liposarcoma (LPS) are classified into subtypes: well-differentiated (WDLPS), de-differentiated (DDLPS), myxoid (MLPS) and pleomorphic (PLS). We report a single institution cohort of patients with LPS, undergoing surgery and radiotherapy, to explore prognostic factors related to outcome and toxicity. Methods: This retrospective analysis included 186 LPS patients. Patient, tumor, and treatment variables were analyzed for local recurrence (LR-DFS) and distant metastasis (DM-DFS) disease free survival and overall survival (OS). Results: At a median follow-up of 8.6 years (range, 0.1-27.3 years), Kaplan-Meier (KM) survival analysis showed that LR, DM and OS were 75.5%, 76.6% and 48.1%, respectively. KM analysis showed that Age>56, DDLPS and lower limb localization were related to LR (p=0,001, p=0,0001 and p=0,0001, respectively). Association between LR, Age and DDLPS persisted both at univariate (p=0,003 and p=0,0001, respectively) and multivariate Cox regression (CR) analysis (p=0,024 and p=0,002). Age, tumor depth and grading influenced distant recurrence, both at KM (p=0,023, p = 0.026 and p = 0.016) and univariate CR (p=0,026, p=0,042 and p=0,012). Age and grading were confirmed at multivariate analysis (p=0,009 and p 0,017). Patients with WDLPS and wide excision had significantly better OS (p=0,001 and p=0,03, respectively), while histologic G3 and age>56 were related with worse OS (p= 0,008 and p=0,0001, respectively). Age, DDLPS and Grade were related to OS at univariate (p=0,0001, p=0,0001 and p=0,03, respectively) and multivariate CR analysis (p=0,031, p=0,0001 and p=0,001, respectively). Conclusions: Our analysis confirmed that Grade, tumor depth and histological subtype influenced survival. Further studies are needed in order to explore the influence of hystopathologic features on treatment outcomes. [Table: see text]

Abstract P5-11-02: Impact of pre-operative exercise and mind-body interventions on patient-reported outcomes in women with newly diagnosed breast cancer

Background: Breast cancer diagnosis has a number of adverse psychological effects. The Pre-Operative Health and Body (PreHAB) Study tested the impact of exercise and mind-body interventions upon on mood, quality of life, and patient-reported outcomes in women with newly diagnosed breast cancer.

Methods: Women with newly diagnosed Stage I-III breast cancer were enrolled through Dana-Farber Cancer Institute and Yale University breast cancer clinics prior to surgery. Participants were randomized 1:1 to an aerobic and strength-training exercise intervention, comprised of twice-weekly meetings with an exercise trainer and home based aerobic exercise, or to a self-directed mind-body relaxation intervention, comprised of a book and CD focused on relaxation and visualization. Participants engaged in the interventions between enrollment and surgery. The EORTC QLQ C-30, Hospital Anxiety and Depression Scale, and Perceived Stress Scale were collected at enrollment and prior to surgery.

Results: 49 women were randomized (27 exercise and 22 control). Mean time between enrollment and surgery was 4.2 weeks. At baseline, patients reported moderate levels of anxiety, stress, insomnia, and lack of appetite, as well as diminished emotional and cognitive functioning (Table). Exercise participants significantly increased minutes of weekly exercise vs. mind-body participants (increase of 203 vs. 23 min/wk, p&lt;0.0001). Mind body participants engaged in the intervention on average 69% of days during the intervention period. Pre-post changes demonstrated that participation in the mind-body intervention led to improvements in emotional and cognitive functioning and a reduction in anxiety and stress, and participation in the exercise intervention led to improvements in global quality of life, insomnia, appetite, and stress (Table). Women in the mind-body group experienced a significantly greater improvement in cognitive functioning as compared to women in the exercise group.

Conclusions: Women with newly diagnosed breast cancer reported a number of physical and psychological symptoms in the pre-operative period. Exercise and mind-body interventions demonstrated promising benefits in improving functioning and reducing symptoms. More work is needed to develop pre-operative programs to help reduce the distress imparted by a cancer diagnosis in the critical time between diagnosis and surgery.

Table*

 Exercise Mind Body Between Groups BaselineChangep valueBaselineChangep valuep valueEmotional Functioning68.6 (23.3)4.7 (18.3)0.2966.3 (24.2)10.0 (20.5)0.050.64Cognitive Functioning79.5 (24.6)-3.3 (24.1)0.6273.8 (22.1)11.7 (15.4)0.0020.03QOL74.0 (15.3)9.7 (15.9)0.00569.0 (21.1)7.5 (18.5)0.110.78Insomnia35.9 (32.6)-16.7 (32.6)0.0334.9 (35.7)-8.3 (21.3)0.060.52Lack of Appetite17.9 (27.0)-13.3 (27.2)0.0311.1 (19.2)-5.0 (22.4)0.530.29Anxiety8.3 (3.4)-0.6 (2.9)0.259.2 (2.5)-1.6 (2.3)0.0060.35Stress14.7 (7.2)-2.2 (4.9)0.0618.4 (5.5)-3.1 (6.8)0.060.77

*Results reported as means (SD). Positive scores on functional and QOL measures indicate improvements; negative scores on symptom measures indicate a decrease in symptoms.

Citation Format: Ligibel JA, Giobbie-Hurder A, Dillion D, Shockro L, Campbell N, Rhei E, Troyan S, Dominici L, Golshan M, Chagpar A, Yung R, Freedman R, Tolaney S, Winer E, Frank E, McTiernan A, Irwin M. Impact of pre-operative exercise and mind-body interventions on patient-reported outcomes in women with newly diagnosed breast cancer [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 P5-11-02.

Abstract P6-18-03: Tumor profiling of inflammatory breast cancer: Advancing the tools needed for precision medicine

Introduction: Inflammatory breast cancer (IBC) is a rare and highly lethal form of breast cancer, accounting for approximately 10% of breast cancer mortality in the US. The clinical presentation of IBC includes rapid onset of symptoms, erythema &gt; 1/3 of the breast, and edema. The genomic changes underlying the clincopathologic manifestations of IBC are yet unknown. Identification of a unique molecular signature in de novo IBC may provide insight into the biology of this disease, allowing further investigation into the etiology and treatment of this aggressive disease. In previous studies, supervised analysis of gene expression data from surgical tissue specimens identified a molecular-subtype independent 79-gene signature associated with IBC compared to locally-advanced non-IBC. In this study, we propose to identify a gene expression signature associated with IBC using breast specimens collected from patients with non-metastatic IBC prior to initiating preoperative systemic treatment.

Methods: Formalin fixed paraffin embedded (FFPE) core biopsy specimens were collected from patients with inflammatory breast cancer prior to initiating systemic therapy. All specimens underwent centralized pathology review at Brigham and Women's Hospital, and the clinical diagnosis was confirmed through evaluation by the Dana Farber Cancer Institute Inflammatory Breast Cancer Program. Sufficient RNA and DNA were simultaneously extracted from 14 biopsy specimens using the Qiagen AllPrep Kit. The RNA was amplified using the Sensation kit and profiled using the Affymetrix Human Transcriptome Array (HTA) 2.0. DNA was profiled for druggable somatic mutations and genome-wide copy number variations using the Affymetrix OncoScan Array.

Results: Pearson correlation coefficients for overall gene expression for 4 technical replicates included in the HTA ranged from r=0.993 - 0.994 and suggest excellent reproducibility in archival biopsy tissue. In preliminary analyses, 765 mRNA transcripts and 335 non-coding transcripts were differentially expressed based on clinical presentation features. The strongest differential association for rapid onset of disease was observed for alternately spliced variants in the TSPAN1 gene. Somatic mutations in PIK3CA were detected in 3 of the IBC patients. Additional paired assays as well as single-gene and pathway analyses, and integrated analyses of the genome and transcriptome using the R/Bioconductor packages are ongoing.

Conclusion: An understanding of the genomic changes that contribute to the unique presentation and biologic features associated with IBC should lead to a significant impact on identifying etiologic risk factors and in optimizing treatment strategies. Our findings to date suggest a robust and reproducible method for genomic investigation using standard diagnostic breast core biopsies among IBC patients, and may inform profiling of biopsy specimens for other cancer types. The completion of this study will provide biological insights into the molecular mechanisms driving IBC and may identify clinically actionable targets for novel IBC therapies that warrant further exploration.

Citation Format: Hazra A, Warren L, Nakhlis F, Bellon JR, Hirshfield-Bartek J, Jacene H, Yeh ED, Dominici L, Schlosnagle E, Hirko K, Overmoyer B. Tumor profiling of inflammatory breast cancer: Advancing the tools needed for precision medicine. [abstract]. In: Proceedings of the Thirty-Eighth Annual CTRC-AACR San Antonio Breast Cancer Symposium: 2015 Dec 8-12; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2016;76(4 Suppl):Abstract nr P6-18-03.

Real-space collapse of a polariton condensate

Microcavity polaritons are two-dimensional bosonic fluids with strong nonlinearities, composed of coupled photonic and electronic excitations. In their condensed form, they display quantum hydrodynamic features similar to atomic Bose-Einstein condensates, such as long-range coherence, superfluidity and quantized vorticity. Here we report the unique phenomenology that is observed when a pulse of light impacts the polariton vacuum: the fluid which is suddenly created does not splash but instead coheres into a very bright spot. The real-space collapse into a sharp peak is at odd with the repulsive interactions of polaritons and their positive mass, suggesting that an unconventional mechanism is at play. Our modelling devises a possible explanation in the self-trapping due to a local heating of the crystal lattice, that can be described as a collective polaron formed by a polariton condensate. These observations hint at the polariton fluid dynamics in conditions of extreme intensities and ultrafast times.

Primary DNA damage in welders occupationally exposed to extremely-low-frequency magnetic fields (ELF-MF)

BACKGROUND

Electric arc welding is known to involve considerable exposure to extremely-low-frequency magnetic fields (ELF-MF; 50 Hz). The aim of the present study was to evaluate individual exposure to ELF-MF during arc welding and to assess the eventually associated genotoxic hazard by evaluating primary DNA damage.

METHODS

The study group comprised 21 electric arc welders (exposed) and 21 non-exposed control subjects (healthy blood donors). Occupational exposure to ELF-MF was measured using personal dosimeters worn during one complete work-shift (7 am to 5 pm). The extent of primary DNA damage was measured in peripheral blood leukocytes with the standard procedure of the alkaline comet assay.

RESULTS

Tail length showed to have similar values in welders and controls. Whereas, the data showed a significant decrease for tail intensity (p = 0.01) and tail moment (p = 0.02) counts in exposed subjects compared to controls.

CONCLUSIONS

The different results of our present study and published investigations from other research groups reporting positive results in the comet assay might be a result of different chromium and/or nickel (or other metals) exposure levels, which lead to DNA-protein cross-links at lower concentrations and DNA single-strand breakages at higher concentrations. Since these results are derived from a small-scale pilot study, a larger scale study should be undertaken.

In Vitro Safety/Protection Assessment of Resveratrol and Pterostilbene in a Human Hepatoma Cell Line (HepG2)

The aim of this work was to evaluate in vitro the genotoxic and/or antigenotoxic effects of resveratrol (RESV) and pterostilbene (PTER) on HepG2 cells. Moreover, additional tests were performed to evaluate early and late apoptosis events induced by the tested stilbenes. RESV and PTER did not show any genotoxic activity. As regards antigenotoxicity testing, RESV and PTER showed a typical, U-shaped hormetic dose-response relationship characterized by a biphasic trend with small quantities having opposite effects to large ones. HepG2 cells treated with PTER exhibited a marked increase in early apoptosis (40.1 %) at 250 μM; whereas, the highest concentration tested for both RESV and PTER significantly increased the proportion of HepG2 cells undergoing late apoptosis (32.5 and 51.2 %, respectively). The observed pro-apoptotic activity could, at least in part, explain the hormetic response observed when the compounds were tested for antigenotoxicity ( i.e., in the presence of induced DNA damage).

In Vitro Safety/Protection Assessment of Resveratrol and Pterostilbene in a Human Hepatoma Cell Line (HepG2)

The aim of this work was to evaluate in vitro the genotoxic and/or antigenotoxic effects of resveratrol (RESV) and pterostilbene (PTER) on HepG2 cells. Moreover, additional tests were performed to evaluate early and late apoptosis events induced by the tested stilbenes. RESV and PTER did not show any genotoxic activity. As regards antigenotoxicity testing, RESV and PTER showed a typical, U-shaped hormetic dose-response relationship characterized by a biphasic trend with small quantities having opposite effects to large ones. HepG2 cells treated with PTER exhibited a marked increase in early apoptosis (40.1%) at 250 microM; whereas, the highest concentration tested for both RESV and PTER significantly increased the proportion of HepG2 cells undergoing late apoptosis (32.5 and 51.2%, respectively). The observed pro-apoptotic activity could, at least in part, explain the hormetic response observed when the compounds were tested for antigenotoxicity (i.e., in the presence of induced DNA damage).

Monitoring of volatile and non-volatile urban air genotoxins using bacteria, human cells and plants

Urban air contains many mutagenic pollutants. This research aimed to investigate the presence of mutagens in the air by short-term mutagenicity tests using bacteria, human cells and plants. Inflorescences of Tradescantia were exposed to air in situ for 6h, once a month from January to May, to monitor volatile compounds and micronuclei frequency was computed. On the same days PM10 was collected continuously for 24h. Half of each filter was extracted with organic solvents and studied by means of the Ames test, using Salmonella typhimurium TA98 and TA100 strains, and the comet assay on human leukocytes. A quarter of each filter was extracted with distilled water in which Tradescantia was exposed. PM10 concentration was particularly high in the winter season (> 50 μg/m(3)). In situ exposure of inflorescences to urban air induced a significant increase in micronuclei frequency at all the sites considered, but only in January (p < 0.01). Aqueous extracts collected in January and February induced genotoxic effects in Tradescantia exposed in the laboratory (p < 0.01). Ames test showed that organic extracts of winter urban air were able to induce genetic mutations in S. typhimurium TA98 strain (± S9), but not in TA100 strain, with a revertants/plate number nine times higher than the negative control. Comet assay showed that winter extracts were more toxic and genotoxic than spring extracts. All the mutagenicity tests performed confirmed that urban air in North Italy in winter contains both volatile and non-volatile genotoxic substances able to induce genetic damage in bacteria, human cells and plants.

Ultrafast Control and Rabi Oscillations of Polaritons

We report the experimental observation and control of space and time-resolved light-matter Rabi oscillations in a microcavity. Our setup precision and the system coherence are so high that coherent control can be implemented with amplification or switching off of the oscillations and even erasing of the polariton density by optical pulses. The data are reproduced by a quantum optical model with excellent accuracy, providing new insights on the key components that rule the polariton dynamics.