Στην βιολογία, το περιβάλλον μπορεί να καθοριστεί σαν ενα σύνολο κλιματικών, βιοτικών, κοινωνικών και εδαφικών παραγόντων που δρουν σε έναν οργανισμό και καθορίζουν την ανάπτυξη και την επιβίωση του. Έτσι, περιλαμβάνει οτιδήποτε μπορεί να επηρεάσει άμεσα τον μεταβολισμό ή τη συμπεριφορά των ζωντανών οργανισμών ή ειδών, όπως το φως, ο αέρας, το νερό, το έδαφος και άλλοι παράγοντες. Δείτε επίσης το άρθρο για το φυσικό περιβάλλον και τη φυσική επιλογή.
Στην αρχιτεκτονική, την εργονομία και την ασφάλεια στην εργασία, περιβάλλον είναι το σύνολο των χαρακτηριστικών ενός δωματίου ή κτιρίου που επηρεάζουν την ποιότητα ζωής και την αποδοτικότητα, περιλαμβανομένων των διαστάσεων και της διαρρύθμισης των χώρων διαβίωσης και της επίπλωσης, του φωτισμού, του αερισμού, της θερμοκρασίας, του θορύβου κλπ. Επίσης μπορεί να αναφέρεται στο σύνολο των δομικών κατασκευών. Δείτε επίσης το άρθρο για το δομημένο περιβάλλον.
Στην ψυχολογία, περιβαλλοντισμός είναι η θεωρία ότι το περιβάλλον (με τη γενική και κοινωνική έννοια) παίζει μεγαλύτερο ρόλο από την κληρονομικότητα καθορίζοντας την ανάπτυξη ενός ατόμου. Συγκεκριμένα, το περιβάλλον είναι ένας σημαντικός παράγοντας πολλών ψυχολογικών θεωριών.
Στην τέχνη, το περιβάλλον αποτελεί κινητήριο μοχλό και μούσα εμπνέοντας τους ζωγράφους ή τους ποιητές. Σε όλες τις μορφές της Τέχνης αποτελεί έμπνευση και οι Καλές Τέχνες φανερώνουν την επιρροή οπού άσκησε σε όλους τους καλλιτέχνες με όποιο είδος Τέχνης κι αν ασχολούνται. Ο άνθρωπος μέσα στο περιβάλλον δημιουργεί Μουσική, Ζωγραφική, Ποίηση, Γλυπτική, χορό, τραγούδι, θέατρο, αλλά και όλες οι μορφές τέχνης έχουν άμεση έμπνευση από το περιβάλλον.

Σάββατο 29 Ιουνίου 2019

Strahlentherapie und Onkologie

Vitamin D und Omega-3-Fettsäuren senken das Risiko für Krebs und kardiovaskuläre Ereignisse nicht


Durvalumab nach einer Radiochemotherapie ist beim NSCLC im Stadium III derzeit die vielversprechendste Therapie


Radiochirurgie und operative neurovaskuläre Dekompression annähernd gleichwertig bei der Behandlung von Trigeminusneuralgien


Tomotherapy in malignant mesothelioma: a planning study to establish dose constraints

Abstract

Purpose

A planning study was performed for helical tomotherapy treatment. We evaluated the maximum achievable protection of organs at risk (OARs) in patients with malignant pleural mesothelioma after pleurectomy with simultaneous optimal target coverage.

Materials and methods

The datasets of 13 patients were included. The applied dose to the planning target volume (PTV) was 50.4 Gy with single doses of 1.8 Gy per fraction. Presuming optimal target coverage, we evaluated the applied dose to the OARs with special regard to the contralateral lung.

Results

For left-(lsRT)/right(rsRT)-sided radiotherapy, target coverage for the PTV showed a D98 (mean) of 49.37/49.71 Gy (98.0%/98.6%) and a D2 (mean) of 54.19/54.61 Gy (107.5%/108.3%). The beam-on time was kept below 15 min. The achieved mean dose (D50) to the contralateral lung was kept below 4 Gy for lsRT and rsRT. With regard to the other organs at risk the applied doses were as follows: mean dose (lsRT): ipsilateral kidney (Dmean) 13.03 (5.32–22.18) Gy, contralateral kidney (Dmean) <2.0 Gy, heart (Dmean) 22.23 (13.57–27.72) Gy, spinal cord D1 <Gy; mean dose (rsRT): ipsilateral kidney (Dmean) 10.22 (6.30–18.04) Gy, contralateral kidney (Dmean) <2.1 Gy, heart (Dmean) 8.02 (6.0–10.38) Gy, spinal cord D1 <35.5 Gy.

Conclusion

With helical tomotherapy, postoperative treatment for malignant pleural mesothelioma after pleurectomy achieves good target coverage combined with simultaneous dose sparing to the (especially contralateral) OARs.



Chemoradiotherapy with and without deep regional hyperthermia for squamous cell carcinoma of the anus

Abstract

Purpose

To compare results after chemoradiotherapy with and without deep regional hyperthermia in patients with anal cancer.

Methods

Between 2000 and 2015, a total of 112 consecutive patients with UICC stage I–IV anal cancer received chemoradiotherapy with 5‑fluororuracil and mitomycin C (CRT). In case of insufficient tumor response 4–6 weeks after chemoradiotherapy, patients received an interstitial pulsed-dose-rate brachytherapy boost. Additionally, 50/112 patients received hyperthermia treatments (HCRT).

Results

Median follow-up was 41 (2–165) months. After 5 years follow-up, overall (95.8 vs. 74.5%, P = 0.045), disease-free (89.1 vs. 70.4%, P = 0.027), local recurrence-free (97.7 vs. 78.7%, P = 0.006), and colostomy-free survival rates (87.7 vs. 69.0%, P = 0.016) were better for the HCRT group. Disease-specific, regional failure-free, and distant metastasis-free survival rates showed no significant differences. The adjusted hazard ratios for death were 0.25 (95% CI, 0.07 to 0.92; P = 0.036) and for local recurrence 0.14 (95% CI, 0.02 to 1.09; P = 0.06), respectively. Grades 3–4 early toxicities were comparable with the exception of hematotoxicity, which was higher in the HCRT group (66 vs. 43%, P = 0.032). Incidences of late side effects were similar with the exception of a higher telangiectasia rate in the HCRT group (38.0 vs. 16.1%, P = 0.009).

Conclusion

Additional regional hyperthermia improved overall survival, local control, and colostomy rates. Its potential beneficial role has to be confirmed in a prospective randomized setting. Therefore, the HyCAN trial has already been established by our group and is currently recruiting patients (Clinicaltrials.gov identifier: NCT02369939).



Consolidative mediastinal irradiation of malignant lymphoma using active scanning proton beams: clinical outcome and dosimetric comparison

Abstract

Purpose

Current research approaches in lymphoma focus on reduction of therapy-associated long-term side effects. Especially in mediastinal lymphoma, proton beam radiotherapy (PT) may be a promising approach for reducing the dose to organs at risk (OAR).

Patients

In total, 20 patients were irradiated with active scanning PT at Heidelberg Ion Beam Therapy Center (HIT) between September 2014 and February 2017. For comparative analysis, additional photon irradiation plans with helical intensity-modulated radiotherapy (IMRT) were calculated and quantitative and qualitative dose evaluations were made for both treatment modalities. Toxicity and survival outcomes were evaluated.

Results

Clinical target volume coverage was comparable in both treatment modalities and did not significantly differ between IMRT and PT. Nevertheless, PT showed superiority regarding the homogeneity index (HIPT = 1.041 vs. HIIMRT = 1.075, p < 0.001). For all OAR, PT showed significantly higher dose reductions compared with IMRT. In particular, the dose to the heart was reduced in PT (absolute dose reduction of Dmean of 3.3 Gy [all patients] and 4.2 Gy [patients with pericardial involvement]). Likewise, the subgroup analysis of female patients, who were expected to receive higher doses to the breast, showed a higher dose reduction in Dmean of 1.2 Gy (right side) and 2.2 Gy (left side). After a median follow-up of 32 months (range 21–48 months), local and distant progression free survival (LPFS and DPFS) were 95.5% and 95.0%, respectively. Radiotherapy was tolerated well with only mild (grade 1–2) radiation-induced acute and chronic side effects.

Conclusion

A significant reduction in the dose to the surrounding OAR was achieved with PT compared with photon irradiation, without compromising target volume coverage. Dosimetric advantages may have the potential to translate into a reduction of long-term radiation-induced toxicity in young patients with malignant lymphoma of the mediastinum.



Influence of XRCC4 expression by breast cancer cells on ipsilateral recurrence after breast-conserving therapy

Abstract

Background

We examined the expression of nonhomologous end-joining (NHEJ) proteins by breast cancer cells in patients with or without ipsilateral breast tumor recurrence (IBTR) after breast-conserving therapy. We also investigated whether there was a difference of NHEJ-related protein expression by tumor cells between two types of IBTR, i.e., true recurrence (TR) with regrowth from the tumor bed or development of a new primary tumor (NP).

Patients and methods

The original cohort comprised 560 breast cancer patients who received breast-conserving therapy between February 1995 and March 2006, including 520 patients without IBTR and 40 patients with IBTR. Propensity score matching was employed to select 40 trios (120 patients) consisting of 1 patient with IBTR and 2 patients without IBTR. Immunohistochemical examination of proteins related to NHEJ was performed in surgical specimens.

Results

The 40 patients with IBTR included 22 patients who developed TR and 18 who had NP. The 15-year overall survival rate was 85.9% for patients with NP and 95.5% for those with TR, while it was 96.5% for patients without IBTR. Patients with high XRCC4 expression in tumor cells had significantly higher IBTR rates than those with low XRCC4 expression (P < 0.001). The frequency of TR was significantly higher in patients with high expression of XRCC4 than in those with low XRCC4 expression (p < 0.001). XRCC4 expression by tumor cells was not significantly related to development of NP.

Conclusion

IBTR due to TR may be related to low radiosensitivity of tumor cells, possibly related to high XRCC4 expression.



Risk of cardiotoxicity induced by adjuvant anthracycline-based chemotherapy and radiotherapy in young and old Asian women with breast cancer

Abstract

Purpose

The risk of cardiotoxicity induced by adjuvant anthracycline-based chemotherapy (CT) and radiotherapy (RT) is yet to be investigated in a large-scale randomized controlled trial with an adequate sample size of young and old women with breast cancer.

Patients and methods

To compare the occurrence of major heart events (heart failure and coronary artery disease) in patients with breast cancer, 3489 women who underwent surgical resection of the breast tumor were retrospectively selected from the Taiwan National Health Insurance Research Database. The patients were categorized into the following groups based on their treatment modalities: group 1 (n = 1113), no treatment; group 2 (n = 646), adjuvant RT alone; group 3 (n = 705), adjuvant anthracycline-based CT alone; and group 4 (n = 1025), combined adjuvant RT and anthracycline-based CT.

Results

The mean patient age was 50.35 years. Subsequent coronary artery disease and heart failure were identified in 244 (7.0%) and 206 (5.9%) patients, respectively. All three adjuvant therapies were significant independent prognostic factors of major heart events (adjusted hazard ratio [95% confidence interval]: 1.47 [1.24–1.73]; 1.48 [1.25–1.75], and 1.92 [1.65–2.23] in groups 2, 3, and 4, respectively). In patients aged ≥50 years with breast cancer who underwent surgery, the log-rank p values of groups 2 and 3 after adjustment were 0.537 and 0.001, respectively.

Conclusion

Adjuvant RT can increase cardiotoxicity in patients with breast cancer, particularly when used in combination with anthracycline-based CT. Therefore, it should be offered with optimal heart-sparing techniques, particularly in younger patients with good prognosis and long life expectancy.



Long-term cosmetic outcome after preoperative radio-/chemotherapy in locally advanced breast cancer patients

Abstract

Background

Preoperative radiotherapy and chemoradiotherapy (PRT/PCRT) represent an increasingly used clinical strategy in different tumor sites. We have previously reported on a PRT/PRCT protocol in patients with locally advanced non-inflammatory breast cancer (LABC) with promising clinical results. However, concerns regarding a possible unfavorable influence on cosmesis still exist. Thus, the aim of the current study was to examine long-term cosmetic outcome in our series of LABC patients treated with PRT/PCRT followed by breast-conserving surgery (BCS) or mastectomy (ME).

Patients and methods

Of the 315 patients treated with PRT/PCRT in the years 1991 to 1999, 203 were still alive at long-term follow-up of mean 17.7 years (range 14–21). Thirty-seven patients were lost to follow-up and 58 patients refused to be contacted, which resulted in 107 patients (64 patients after BCS and 43 after mastectomy) being available and willing to undergo further cosmetic assessment. One patient had a complete response after PRT/PCRT and refused surgery. PRT/PCRT consisted of external beam radiation therapy (EBRT) with 50 Gy (5 × 2 Gy/week) to the breast and the supra-/infraclavicular lymph nodes combined with a consecutive electron boost or (in case of BCS) a 10-Gy interstitial brachytherapy boost with Ir-192 prior to EBRT. Overall, chemotherapy was administered either prior to RT or concomitantly in the majority of patients. BCS and mastectomy were performed with and without reconstruction. The cosmetic outcome was assessed by patient questionnaire, panel evaluation, and breast retraction assessment (BRA) score.

Results

Eighty percent of all BCS patients rated their overall cosmetic result as "excellent" or "good" as compared to 55.8% after mastectomy. Patient and panel ratings on cosmetic outcomes were similar between the two groups. No grade III or IV fibrosis were detected in any of the groups. The median BRA score after breast conserving surgery was 2.9.

Conclusion

PRT/PCRT is associated with low grades of fibrosis and a good to excellent long-term cosmetic outcome.



Single-center long-term results from the randomized phase-3 TARGIT-A trial comparing intraoperative and whole-breast radiation therapy for early breast cancer

Abstract

Purpose

Partial breast irradiation using intraoperative radiotherapy (IORT) after breast-conserving surgery could be sufficient for a selected group of breast cancer patients. We report the results of a cohort of patients from a single center treated as part of the randomized phase-3 TARGIT-A trial.

Methods

Patients (≥50 years) with cT1 cN0 cM0 and invasive ductal histology on biopsy were randomized between IORT with 20 Gy (arm-A) or postoperative whole-breast RT (WBRT) up to 56 Gy in 2 Gy fractions (arm-B). Postoperatively, patients in arm-A with multifocality, lymphovascular invasion, nodal invasion, extensive intraductal component, invasive lobular carcinoma, or resection margins <1 cm received additional postoperative WBRT.

Results

Between 2002 and 2012, 184 patients were randomized, of whom 90 in arm-A and 90 in arm-B were evaluated. Median follow-up was 8.5 years. The 5‑year overall survival was 94.4% in arm-A and 93.3% in arm-B (p = 0.73). Two local recurrences were observed: one at 70.3 months in an arm-A patient who received IORT + WBRT and another at 4.5 months in an arm-B patient who refused all forms of adjuvant treatment, thus resulting in a 5-year local recurrence of 0% in arm-A and 1.1% in arm-B. The 5‑year in-breast recurrence (outside of the index quadrant) was 0% in arm-A and 1.2% in arm-B. Salvage mastectomy was performed successfully in all patients with relapse.

Conclusion

Long-term follow-up of this single-center cohort consolidates the earlier reports of low local recurrence rates after single-dose IORT. Our results are in line with non-inferiority of risk-adapted IORT for selected patients with early breast cancer.



Alexandros Sfakianakis
Anapafseos 5 . Agios Nikolaos
Crete.Greece.72100
2841026182
6948891480

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