Publications by authors named "Ana Luisa Vasconcelos"

8 Publications

  • Page 1 of 1

Positron Emission Tomography-Derived Metrics Predict the Probability of Local Relapse After Oligometastasis-Directed Ablative Radiation Therapy.

Adv Radiat Oncol 2022 Mar-Apr;7(2):100864. Epub 2021 Dec 5.

Department of Radiation Oncology, Champalimaud Centre for the Unknown, Lisbon, Portugal.

Purpose: Early positron emission tomography-derived metrics post-oligometastasis radioablation may predict impending local relapses (LRs), providing a basis for a timely ablation.

Methods And Materials: Positron emission tomography data of 623 lesions treated with either 24 Gy single-dose radiation therapy (SDRT) (n = 475) or 3 ×  9 Gy stereotactic body radiation therapy (SBRT) (n = 148) were analyzed in a training data set (n = 246) to obtain optimal cutoffs for pretreatment maximum standardized uptake value (SUV) and its 3-month posttreatment decline (ΔSUV) in predicting LR risk, validated in a data set unseen to testing (n = 377).

Results: At a median of 21.7 months, 91 lesions developed LRs: 39 of 475 (8.2%) after SDRT and 52 of 148 (35.1%) after SBRT. The optimal cutoff values were 12 for SUV and -75% for ΔSUV. Bivariate SUV/ΔSUV permutations rendered a 3-tiered LR risk stratification of dual-favorable (low risk), 1 adverse (intermediate risk) and dual-adverse (high risk). Actuarial 5-year local relapse-free survival rates were 93.9% versus 89.6% versus 57.1% ( < .0001) and 76.1% versus 48.3% versus 8.2% ( < .0001) for SDRT and SBRT, respectively. The SBRT area under the ROC curve was 0.71 (95% CI, 0.61-0.79) and the high-risk subgroup yielded a 76.5% true positive LR prediction rate.

Conclusions: The SBRT dual-adverse SUV/ΔSUV category LR prediction power provides a basis for prospective studies testing whether a timely ablation of impending LRs affects oligometastasis outcomes.
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http://dx.doi.org/10.1016/j.adro.2021.100864DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC8752878PMC
December 2021

Plant neighborhood shapes diversity and reduces interspecific variation of the phyllosphere microbiome.

ISME J 2022 05 12;16(5):1376-1387. Epub 2022 Jan 12.

Department of Integrative Biology, University of California, Berkeley, Berkeley, CA, 94720, USA.

Microbial communities associated with plant leaf surfaces (i.e., the phyllosphere) are increasingly recognized for their role in plant health. While accumulating evidence suggests a role for host filtering of its microbiota, far less is known about how community composition is shaped by dispersal, including from neighboring plants. We experimentally manipulated the local plant neighborhood within which tomato, pepper, or bean plants were grown in a 3-month field trial. Focal plants were grown in the presence of con- or hetero-specific neighbors (or no neighbors) in a fully factorial combination. At 30-day intervals, focal plants were harvested and replaced with a new age- and species-matched cohort while allowing neighborhood plants to continue growing. Bacterial community profiling revealed that the strength of host filtering effects (i.e., interspecific differences in composition) decreased over time. In contrast, the strength of neighborhood effects increased over time, suggesting dispersal from neighboring plants becomes more important as neighboring plant biomass increases. We next implemented a cross-inoculation study in the greenhouse using inoculum generated from the field plants to directly test host filtering of microbiomes while controlling for directionality and source of dispersal. This experiment further demonstrated that focal host species, the host from which the microbiome came, and in one case the donor hosts' neighbors, contribute to variation in phyllosphere bacterial composition. Overall, our results suggest that local dispersal is a key factor in phyllosphere assembly, and that demographic factors such as nearby neighbor identity and biomass or age are important determinants of phyllosphere microbiome diversity.
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http://dx.doi.org/10.1038/s41396-021-01184-6DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC9038669PMC
May 2022

Pretreatment hemoglobin level as a prognostic factor in patients with locally advanced head and neck squamous cell carcinoma.

Rep Pract Oncol Radiother 2020 Sep-Oct;25(5):768-774. Epub 2020 Jul 28.

Medical Oncology Department, Hospital de Santa Maria, Centro Hospitalar Universitário Lisboa Norte, Lisbon 1649-035, Portugal.

Aim: Evaluate pretreatment hemoglobin values as a prognostic factor in patients with locally advanced head and neck squamous cell carcinoma treated with concurrent chemoradiotherapy.

Background: Anemia is one of the most prevalent laboratory abnormalities in oncological disease. It leads to a decrease in cellular oxygen supply, altering radiosensitivity of tumor cells and compromising therapeutic outcomes.

Materials And Methods: Retrospective evaluation of patients with HNSCC treated with cCRT. Primary and secondary endpoint was to evaluate the correlation of Hb levels (≥12.5 g/dL or <12.5 g/dL) at the beginning of cCRT with overall survival (OS) and progression-free survival (PFS), respectively.

Results: A total of 108 patients were identified. With a median follow-up of 16.10 months median OS was 59.70 months for Hb ≥12.5 g/dL vs. 14.13 months for Hb <12.5 g/dL ( = 0.004). PFS was 12.29 months for Hb ≥12.5 g/dL and 1.68 months for Hb <12.5 g/dL ( = 0.016).

Conclusions: In this analysis, Hb ≥12.5 g/dL correlated with significantly better OS and PFS. Further studies are needed to validate these findings.
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http://dx.doi.org/10.1016/j.rpor.2020.07.002DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7413985PMC
July 2020

Target motion mitigation promotes high-precision treatment planning and delivery of extreme hypofractionated prostate cancer radiotherapy: Results from a phase II study.

Radiother Oncol 2020 05 19;146:21-28. Epub 2020 Feb 19.

The Champalimaud Centre for the Unknown, Lisbon, Portugal; Memorial Sloan Kettering Cancer Center, New York, USA.

Background And Purpose: While favourable long-term outcomes have been reported in organ-confined prostate cancer treated with 5 × 7-8 Gy extreme hypofractionation, dose escalation to 5 × 9-10 Gy improved local control but was associated with unacceptable rates of late rectal and urinary toxicities. The purpose of this study was to explore the feasibility of intra-fractional prostate immobilization in reducing toxicity, to promote dose escalation with extreme hypofractionated radiotherapy in prostate cancer.

Material And Methods: 207 patients received 5 consecutive fractions of 9 Gy. An air-inflated (150 cm) endorectal balloon and an intraurethral Foley catheter with 3 beacon transponders were used to immobilize the prostate and monitor intra-fractional target motion. VMAT-IGRT with inverse dose-painting was employed in delivering the PTV dose and in sculpting exposure of normal organs at risk to fulfil dose-volume constraints.

Results: Introduction of air-filled balloon induced repeatable rectum/prostate complex migration from its resting position to a specific retropubic niche, affording the same 3D anatomical configuration daily. Intra-fractional target deviations ≤1 mm occurred in 95% of sessions, while target realignment in ≥2 mm deviations enabled treatment completion as scheduled. Nadir PSA at median 54 months follow-up was 0.19 ng/mL, and bRFS was 100%, 92.4% and 71.4% in low-, intermediate- and high-risk categories, respectively. Late Grade 2 GU and GI toxicities were 2.9% and 2.4%, respectively. No adverse changes in patient-reported quality of life scores were observed.

Conclusion: The unique spatial configuration of this prostate motion mitigation protocol enabled precise treatment planning and delivery that optimized outcomes of ultra-high 5 × 9 Gy hypofractionated radiotherapy of organ-confined prostate cancer.
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http://dx.doi.org/10.1016/j.radonc.2020.01.029DOI Listing
May 2020

The evolving role of external beam radiotherapy in localized prostate cancer.

Semin Oncol 2019 06 22;46(3):246-253. Epub 2019 Aug 22.

The Champalimaud Centre for the Unknown, Lisbon, Portugal; Memorial Sloan Kettering Cancer Center, New York, New York.

Primary organ-confined prostate cancer is curable with external-beam radiotherapy. However, prostate cancer expresses a unique radiobiological phenotype, and its ablation requires doses at the high-end range of clinical radiotherapy. At this dose level, normal tissue radiosensitivity restricts the application of curative treatment, and mandates the use of the most advanced high-precision treatment delivery techniques to spare critical organs at risk. The efficacy and tolerance of dose-escalated conventional fractionated radiotherapy and of the biological equivalent doses of moderate and extreme hypofractionation are reviewed. Current studies indicate that novel risk-adapted techniques to spare normal organs at risk are still required to deploy high-biological equivalent dose extreme hypofractionation, while affording preservation of quality of life and cost-effectiveness.
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http://dx.doi.org/10.1053/j.seminoncol.2019.08.001DOI Listing
June 2019

In vitro exposure to the next-generation plasticizer diisononyl cyclohexane-1,2-dicarboxylate (DINCH): cytotoxicity and genotoxicity assessment in human cells.

J Toxicol Environ Health A 2019 26;82(9):526-536. Epub 2019 Jun 26.

a Department of Human Genetics, National Institute of Health Doutor Ricardo Jorge, I.P. (INSA) , Lisbon , Portugal.

Plasticizers are currently present in many consumer products, particularly food packaging, children's toys, and medical devices. There are concerns regarding potential leaching to environment or food, thus increasing the risk of human exposure by inhalation, ingestion and/or dermal absorption potentially leading to adverse health consequences. Hexamoll diisononyl cyclohexane-1,2-dicarboxylate (Hexamoll® DINCH®), a non-phthalate plasticizer, has been used as a safer alternative to hazardous phthalates. In contrast to phthalates, evidence indicates that DINCH did not produce endocrine disruption, reproductive dysfunctions, genotoxicity or mutagenicity. However, there are limited data available regarding safety assessment, especially with respect to genotoxicity in human cells. The aim of this study was to assess DINCH cytotoxic and genotoxic effects in human liver and kidney cell lines following several exposure periods. For this purpose, the MTT cell viability, micronucleus, conventional and formamidopyrimidine DNA glycosylase (FPG)-modified comet assays were employed to detect cell death and genotoxicity, respectively. Data demonstrated that DINCH induced cytotoxicity in kidney cells exposed for 48hr, but not in liver cells. No marked chromosomal damage was noted after short-term or longer following treatment of both cell lines. However, DINCH produced oxidative DNA damage in liver cells exposed for 3 h, which decreased after a more prolonged incubation period. The occurrence of oxidative lesions, even transiently, indicates that mutation fixation may occur leading to adverse effects in liver. Therefore, these findings suggest that DINCH may be hazardous to humans and that further investigation is necessary to warrant its safety.
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http://dx.doi.org/10.1080/15287394.2019.1634376DOI Listing
May 2020

Interstitial high-dose-rate brachytherapy in eyelid cancer.

Brachytherapy 2015 Jul-Aug;14(4):554-64. Epub 2015 May 7.

Department of Radiotherapy, Hospital de Santa Maria, Centro Hospitalar Lisboa Norte, EPE, Lisbon, Portugal.

Purpose: To report the experience and the outcomes of interstitial high-dose-rate (HDR) brachytherapy (BT) of eyelid skin cancer at the Department of Radiotherapy of Hospital de Santa Maria in Lisbon.

Methods And Materials: Seventeen patients (pts; mean age, 73.75 years) who underwent eyelid interstitial HDR BT with an (192)Ir source between January 2011 and February 2013 were analyzed. Lesions were basal (94%) and squamous (6%) cell carcinomas, on lower (88%) or upper (6%) eyelids, and on inner canthus (6%). T-stage was Tis (6%), T1 (46%), T2 (36%), and T3a (12%). The purpose of BT was radical (12%), adjuvant to surgery (71%), or salvage after surgery (18%). The BT implant and treatment planning were based on the Stepping Source Dosimetry System. The median total dose was 42.75 Gy (range, 32-50 Gy), with a median of 10 fractions (range, 9-11 fractions), twice daily, 6 h apart. The median V100 was 2.38 cm(3) (range, 0.83-5.59 cm(3)), and the median V150 was 1.05 cm(3) (range, 0.24-3.12 cm(3)).

Results: At a median followup of 40 months (range, 7-43 months), the local control was 94.1%. There was one local recurrence and one non-related death. The BT was well tolerated. Madarosis was the most common late effect (65% of pts) and was related with higher values of V100 (p = 0.027). Cosmetic outcomes were good and excellent in 70% of pts.

Conclusions: Interstitial HDR BT is a feasible and safe technique for eyelid skin cancers, with good local control. Recurrent lesions and higher volumes receiving the prescribed dose were associated with worse outcomes.
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http://dx.doi.org/10.1016/j.brachy.2015.03.005DOI Listing
January 2016

Tamoxifen in breast cancer ipse dixit in uterine malignant mixed Müllerian tumor and sarcoma-A report of 8 cases and review of the literature.

Rep Pract Oncol Radiother 2013 Aug 12;18(5):251-60. Epub 2013 Aug 12.

Serviço de Radioterapia Hospital Santa Maria, CHLN, Serviço de Radioterapia do Hospital Santa Maria, Av. Prof. Egas Moniz, 1649-035 Lisboa, Portugal ; Serviço de Oncologia Hospital Santa Maria, CHLN, Serviço de Radioterapia do Hospital Santa Maria, Av. Prof. Egas Moniz, 1649-035 Lisboa, Portugal ; Instituto de Medicina Molecular, FMUL, Serviço de Radioterapia do Hospital Santa Maria, Av. Prof. Egas Moniz, 1649-035 Lisboa, Portugal.

Aim: Report the outcome of 8 patients (pts) with breast cancer (BC) treated with Tamoxifen (TAM) that developed malignant mixed Müllerian tumor (MMMT) and rare uterine sarcoma (RUS).

Patients And Methods: Retrospective study based on data collected from the department medical records between April 1999 and September 2010 among 583 pts with endometrial cancer, 36 pts with MMMT and RUS histopathology. Among them, 8 pts underwent TAM between 4 and 10 years due to a previous diagnosis of BC; all pts were post-menopausal with regular gynecological surveillance; 6 pts (75%) with abnormal uterine bleeding. The diagnosis of 6 pts (MMMT) and 2 pts (RUS) occurred at median interval of 8 years (range 4-12) after initial BC treatment. Pts underwent surgical treatment and were staged as stage I (3pts), IIIA (3pts) and IIIC (2 pts) (FIGO 1988); followed by whole pelvis irradiation (50 Gy) and intracavitary HDR brachytherapy boost (24 Gy). Two pts underwent chemotherapy (CT). Overall and disease free survival was calculated by Kaplan Meier method.

Results: With a median follow-up of 47 months (range 17-130), 3 pts remain alive recurrence-free of BC and RUS. Four pts died with distant metastasis within the first follow-up year, without BC. One pt died from non-related cancer cause. No evidence of local recurrence was found in the whole group of pts. At two years, DFS and OS were 40% and 80%, respectively.

Conclusion: As reported in the literature, TAM administration and causal effect on MMMT and RUS in BC pts is still unknown. No reports about outcome from these specific pts were found.
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http://dx.doi.org/10.1016/j.rpor.2013.06.005DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC3863172PMC
August 2013
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