Publications by authors named "Alptekin Arifoglu"

4 Publications

  • Page 1 of 1

Prognostic factors in medically inoperable early stage lung cancer patients treated with stereotactic ablative radiation therapy (SABR): Turkish Radiation Oncology Society Multicentric Study.

Clin Respir J 2020 Nov 17;14(11):1050-1059. Epub 2020 Aug 17.

Faculty of Medicine, Radiation Oncology Department, Ankara University, Ankara, Turkey.

Objective: We identified factors influencing outcomes in patients with medically inoperable early stage lung cancer (MIESLC) treated with stereotactic ablative radiation therapy (SABR) at 14 centers in Turkey.

Materials And Methods: We retrospectively analyzed 431 patients with stage I-II MIESLC treated with SABR from 2009 through 2017. Age; sex; performance score; imaging technique; tumor histology and size; disease stage radiation dose, fraction and biologically effective dose with an α/β ratio of 10 (BED ); tumor location and treatment center were evaluated for associations with overall survival (OS), local control (LC) and toxicity.

Results: Median follow-up time was 27 months (range 1-115); median SABR dose was 54 Gy (range 30-70) given in a median three fractions (range 1-10); median BED was 151 Gy (range 48-180). Tumors were peripheral in 285 patients (66.1%), central in 69 (16%) and <1 cm from mediastinal structures in 77 (17.9%). Response was evaluated with PET/CT in most cases at a median 3 months after SABR. Response rates were: 48% complete, 36.7% partial, 7.9% stable and 7.4% progression. LC rates were 97.1% at 1 year, 92.6% at 2 years and 91.2% at 3 years; corresponding OS rates were 92.6%, 80.6% and 72.7%. On multivariate analysis, BED > 100 Gy (P = .011), adenocarcinoma (P = .025) and complete response on first evaluation (P = .007) predicted favorable LC. BED > 120 Gy (hazard ratio [HR] 1.9, 95% confidence interval [CI] 1.1-3.2, P = .019) and tumor size (<2 cm HR 1.9, 95% CI 1.3-3, P = .003) predicted favorable OS. No grade 4-5 acute side effects were observed; late effects were grade ≤3 pneumonitis (18 [4.2%]), chest wall pain (11 [2.5%]) and rib fracture (1 [0.2%]).

Conclusion: SABR produced encouraging results, with satisfactory LC and OS and minimal toxicity. BED > 120 Gy was needed for better LC and OS for large, non-adenocarcinoma tumors.
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November 2020

Definitive radiotherapy in locally advanced non-small cell lung cancer: dose and fractionation.

Balkan Med J 2014 Dec 1;31(4):278-85. Epub 2014 Dec 1.

Department of Radiation Oncology, İstanbul University İstanbul Faculty of Medicine, İstanbul, Turkey.

Definitive radiotherapy plays a major role in the treatment of locally advanced non-small cell lung cancer (LA NSCLC). After the impact of RT dose for lung cancer was established, a number of trials were structured with the aim of better local control and overall survival by either dose escalation or shortening the total treatment time through conventional/altered fractionation, even in combination with chemotherapy (CT) and other targeted agents. In spite of the increased number of these studies, the optimal dose or fractionation still remains to be determined. Another aspect questioned is the incorporation of these higher doses and shorter treatment times with chemotherapy or targeted agents. This review summarises the results of significant trials on dose and altered fractionation in the treatment of LA-NSCLC with an emphasis on possible future perspectives.
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December 2014

Critical appraisal of RapidArc radiosurgery with flattening filter free photon beams for benign brain lesions in comparison to GammaKnife: a treatment planning study.

Radiat Oncol 2014 May 21;9:119. Epub 2014 May 21.

Medical Physics Unit, Oncology Institute of Southern Switzerland, 6504 Bellinzona, Switzerland.

Background: To evaluate the role of RapidArc (RA) for stereotactic radiosurgery (SRS) of benign brain lesions in comparison to GammaKnife (GK) based technique.

Methods: Twelve patients with vestibular schwannoma (VS, n = 6) or cavernous sinus meningioma (CSM, n = 6) were planned for both SRS using volumetric modulated arc therapy (VMAT) by RA. 104 MV flattening filter free photon beams with a maximum dose rate of 2400 MU/min were selected. Data were compared against plans optimised for GK. A single dose of 12.5 Gy was prescribed. The primary objective was to assess treatment plan quality. Secondary aim was to appraise treatment efficiency.

Results: For VS, comparing best GK vs. RA plans, homogeneity was 51.7 ± 3.5 vs. 6.4 ± 1.5%; Paddick conformity Index (PCI) resulted 0.81 ± 0.03 vs. 0.84 ± 0.04. Gradient index (PGI) was 2.7 ± 0.2 vs. 3.8 ± 0.6. Mean target dose was 17.1 ± 0.9 vs. 12.9 ± 0.1 Gy. For the brain stem, D(1cm3) was 5.1 ± 2.0 Gy vs 4.8 ± 1.6 Gy. For the ipsilateral cochlea, D(0.1cm3) was 1.7 ± 1.0 Gy vs. 1.8 ± 0.5 Gy. For CSM, homogeneity was 52.3 ± 2.4 vs. 12.4 ± 0.6; PCI: 0.86 ± 0.05 vs. 0.88 ± 0.05; PGI: 2.6 ± 0.1 vs. 3.8 ± 0.5; D(1cm3) to brain stem was 5.4 ± 2.8 Gy vs. 5.2 ± 2.8 Gy; D(0.1cm3) to ipsi-lateral optic nerve was 4.2 ± 2.1 vs. 2.1 ± 1.5 Gy; D(0.1cm3) to optic chiasm was 5.9 ± 3.1 vs. 4.5 ± 2.1 Gy. Treatment time was 53.7 ± 5.8 (64.9 ± 24.3) minutes for GK and 4.8 ± 1.3 (5.0 ± 0.7) minutes for RA for schwannomas (meningiomas).

Conclusions: SRS with RA and FFF beams revealed to be adequate and comparable to GK in terms of target coverage, homogeneity, organs at risk sparing with some gain in terms of treatment efficiency.
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May 2014

Neoadjuvant hyperfractionated-accelerated radiotherapy with concomitant chemotherapy in esophageal cancer: phase II study.

J Gastrointest Oncol 2013 Dec;4(4):380-7

Istanbul Bilim University Medical Faculty, Department of Medical Oncology, Istanbul, Turkey;

Purpose: Concomitant use of chemotherapy and a radiation dose schedule that is more efficient compared to conventional radiotherapy may provide better outcomes in patients with esophageal cancer. This study aimed to assess the efficacy and tolerability of neoadjuvant cisplatin-based chemotherapy and hyperfractionated accelerated radiotherapy regimen in this group of patients.

Methods And Materials: A total of 20 newly diagnosed treatment-naïve esophageal cancer patients were included in the study. Neoadjuvant cisplatin and 5-FU were given with 28-day intervals in a total of three courses. Along with the third course of chemotherapy, hyperfractionated accelerated radiotherapy (HART) was given with the following dose schedule: 5760 cGy/36 fr/16 day.

Results: All patients could receive the planned RT dose of 5760 cGy. Odynophagia was the most frequent grade III acute toxicity (50%). None of the acute toxicity reactions required treatment discontinuation. Grade III or higher subacute/late toxicity occurred in 10 patients (75%) including 5 deaths, mostly esophageal. Radiologically, 8 patients (40%) had complete response, 8 (40%) had partial response, and 3 (15%) had stable disease, with only 1 patient (5%) having progressive disease. Seven patients underwent surgery. Overall, 8 patients (40%) had local control. The 5 years overall survival rate was 38.1%.

Conclusions: Neoadjuvant hyperfractionated accelerated radiotherapy plus chemotherapy may help to target local disease control and increase survival in patients with esophageal cancer. Further studies to improve neoadjuvant and radical chemoradiotherapy dose schedules are warranted for maximum tumor control rates with minimal toxicity.
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December 2013