Reports of Practical Oncology and Radiotherapy最新文献

Background: The purpose was to validate the PRIMO Monte Carlo software to be used during the commissioning of a treatment planning system (TPS).

Materials and methods: The Acuros XB v. 16.1 algorithm of the Eclipse was configured for 6 MV and 6 MV flattening-filter-free (FFF) photon beams, from a TrueBeam linac equipped with a high-definition 120-leaf multileaf collimator (MLC). PRIMO v. 0.3.64.1814 software was used with the phase space files provided by Varian and benchmarked against the reference dosimetry dataset published by the Imaging and Radiation Oncology Core-Houston (IROC-H). Thirty Eclipse clinical intensity-modulated radiation therapy (IMRT)/volumetric modulated arc therapy (VMAT) plans were verified in three ways: 1) using the PTW Octavius 4D (O4D) system; 2) the Varian Portal Dosimetry system and 3) the PRIMO software. Clinical validation of PRIMO was completed by comparing the simulated dose distributions on the O4D phantom against dose measurements for these 30 clinical plans. Agreement evaluations were performed using a 3% global/2 mm gamma index analysis.

Results: PRIMO simulations agreed with the benchmark IROC-H data within 2.0% for both energies. Gamma passing rates (GPRs) from the 30 clinical plan verifications were (6 MV/6MV FFF): 99.4% ± 0.5%/99.9% ± 0.1%, 99.8% ± 0.4%/98.9% ± 1.4%, 99.7% ± 0.4%/99.7% ± 0.4%, for the 1), 2) and 3) verification methods, respectively. Agreement between PRIMO simulations on the O4D phantom and 3D dose measurements resulted in GPRs of 97.9% ± 2.4%/99.7% ± 0.4%.

Conclusion: The PRIMO software is a valuable tool for dosimetric verification of clinical plans during the commissioning of the primary TPS.

Background: Ovarian cancer is a huge therapeutic and financial problem for which approved treatments have already achieved their limit of efficiency. A cost-effective strategy to extend therapeutic options in this malignancy is drug repurposing aimed at overcoming chemoresistance. Here, angiotensin-converting enzyme inhibitors (ACE-I) are worth considering.

Materials and methods: We searched literature for publications supporting the idea of adjuvant application of ACE-Is in ovarian malignancy. Then, we searched The Cancer Genome Atlas databases for relevant alternations of gene expression patterns. We also performed in silico structure-activity relationship evaluation for predicting ACE-Is' cytotoxicity against ovarian cancer cell lines. Finally, we reviewed the potential obstacles in ACE-Is repurposing process.

Results: The alternation of angiotensin receptor expression in ovarian cancer translates into poorer patient survival. This confirms the participation of the renin-angiotensin system in ovarian carcinogenesis. In observational studies, ACE-Is were shown synergize with both, platinum-based chemotherapy as well as with antiangiogenic therapy. Consistently, our in silico simulation showed that ACE-Is are probably cytotoxic against ovarian cancer cells. However, the publications on their chemopreventive properties were inconclusive. In addition, some reports correlated ACE-Is use with increased general cancer incidence. We hypothesized that this effect could be associated with mutagenic nitrosamine formation in ACE-Is' pharmaceutical formulations, as was the case with angiotensin receptor blockers (ARBs) and other well-established pharmaceuticals.

Conclusions: Available data warrant further research into repositioning ACE-Is to ovarian cancer as chemosensitizers. Prior to this, however, a special research program is needed to detect possible genotoxic contaminants of ACE-Is.

Background: The knowledge of the risks induced by radiation with hypofractionation regimens has only recently been estimated together with its implementation as a management standard. However, the dose to other risk organs with intensity-modulated radiation therapy (IMRT) or volumetric modulated arc therapy (VMAT) is not clear, that is why this is only a reference study of radiation doses to organs at risk in hypofractionation in our center.

Materials and methods: We completed a retrospective and observational analysis of 1398 patients treated with adjuvant hypofractionated radiotherapy from 2015 to 2018, using the clinical records and dose-volume histogram of patients treated with moderate hypofractionated adjuvant radiotherapy. To analyze the institutional experience on the dosimetry of the esophagus and liver as risk organs in the use of moderate adjuvant hypofractionated radiotherapy in breast cancer.

Results: The dosimetry of the esophagus was 3271 cGy DMax, 177 cGy DMed, 68 cGy D50%, 500 cGy DcMAX with 3D RT and 4124 cGy DMax, 1242 cGy DMed, 934.50 cGy D50%, 3213 cGy DcMAX with IMRT/VMAT and the dosimetry for the liver was for right breast cancer 466 cGy DMed, 102 cGy D50% and 8% V20, for left breast cancer 22 cGy DMed, 6.10 cGy D50% and 0.3% V20.

Conclusion: The statistically significant differences in irradiation show the lack of consensus on the optimal restrictions in hypofractionation regimens to reduce clinical sequela; consequently, the variability in the specification of each radiation oncologist is observed; standardization in our center can lead to improvement in the quality of treatments.

Background: Whole-brain radiotherapy is associated with neurocognitive decline and decreased quality-of-life (QOL) among survivors of brain metastasis. Hippocampal-avoidance whole-brain radiotherapy (HA-WBRT) has shown advantage in delaying or preventing the neurocognitive decline while maintaining disease control. This study was done to assess the benefits and feasibility of HA-WBRT in patients with cerebral metastasis in terms of preservation of neurocognitive function and quality of life.

Materials and methods: 27 patients with brain metastasis treated by HA-WBRT and having the records of detailed neurocognitive-assessments were analysed from the database of our hospital. The patients were treated with HA-WBRT to a total dose of 30 Gy in 10 fractions with LINAC based IMRT using the VMAT technique. Cognitive function assessment was carried out using "Examination of the Cognitive Functions" scale provided by Bangur-Institute-of-Neurosciences, Kolkata, 2 weeks prior to radiotherapy and post-treatment two-monthly up to 6 months followed by every 3 months till the last follow up. QOL was assessed at the same interval using the Functional Assessment of Cancer Therapy with Brain Subscale (FACT-BR). Follow-up was done till the date of death.

Results: Mean relative cognitive decline percentage decreased over subsequent follow-up visits and was 13% (SD ± 6%), 5% (SD ± 5%), 5% (SD ± 9%) and 2% (SD ± 12%) at 2 months, 6 months, 9 months and 12 months, respectively (p ≤ 0.05). Statistically significant improvement was seen in the mean social-wellbeing (SWB) parameter of QOL (8%. ± 13%, 12%. ± 16%, 7%. ± 20%, no change at 2 months, 4 months, 6 months and 9 months, respectively) (p ≤ 0.05). Mean relative decline in the Emotional-Well Being (EWB) parameter was significant only at 12 months and was 20% (SD ± 35%) (p = 0.04). Mean FACT-BR total Score showed a slight decrease till 9 months from baseline, and then showed a slight improvement up to 12 months.

Conclusion: HA-WBRT is feasible with LINAC-based IMRT using the VMAT technique and beneficial to the patients in preserving neurocognitive function and quality of life without compromising disease control.

Background: Prostate cancer treatment is determined based on several factors, namely tumor grading, staging, co-morbidity, patient preferences, life expectancy at diagnosis. Today, taxanes are commonly prescribed to treat several types of cancer and have been shown to have antitumor effects in many cancers. This research has never been done in prostate cancer patients but similar studies have been done before in breast cancer patients.

Materials and methods: The research design was observational analytic where this type of research was a prospective cohort where data was collected to record prostate cancer patients who received docetaxel chemotherapy which were then examined for thyroid function in cancer patients at the Adam Malik Hospital, Medan, Indonesia.

Result: In this study, data were collected regarding the thyroid function of the study sample in the form of free thyroxine (fT4) and thyroid-stimulating hormone (TSH) levels before chemotherapy with the docetaxel regimen. The mean of fT4 in all research subjects was 1.05 with a standard deviation of 0.26. The mean TSH in all study subjects was 1.52 with a standard deviation of 1.21. Thyroid function was examined after 3 cycles of docetaxel chemotherapy. The mean of fT4 in all research subjects was 0.91 with a standard deviation of 0.23. The mean TSH in all study subjects was 1.69 with a standard deviation of 1.09.

Conclusion: There are traces of the use of docetaxel chemotherapy in prostate cancer patients on decreased thyroid function at the Adam Malik Hospital in the form of decreased fT4 levels and increased TSH.

Background: Radiotherapy (RT) is an appropriate treatment option for early-stage glottic cancer (ESGC) that achieves high local control and preserves voice quality. However, the optimal radiation treatment schedule remains unknown. We present our institution's 14-year experience in treating ESGC with definitive radiotherapy between 2005 and 2019 inclusively.

Materials and methods: We reviewed the medical records of 104 patients; 63 (60.5%) were treated with conventional fractionation (CF), and 41 (39.5%) were treated with hypofractionated radiotherapy (HF). The clinical T-stage was T1a in 50 patients (48%), T1b in 27 (26%), and T2 in 27 (26%). Age, gender, anterior commissure involvement, stage, radiotherapy technique, radiation fraction size, and overall treatment time (OTT) were analyzed as prognostic factors. The survival outcomes, local regional control (LRC), and laryngeal preservation rate were evaluated.

Results: The 5-year overall survival (OS) and LCR were 83.3% and 78%, respectively. On univariate analysis, treatment with CF (p = 0.02), prolonged OTT > 49 days in CF and > 40 days in HF (p = 0.04), and RT total dose < 66 Gy (p = 0.03) were associated with poor LRC. Multivariate analysis showed a non-significant association with LRC (all p > 0.05). The 5-year OS rate in the CF and HF-treated patients was 84.9% and 72.1%, respectively (p = 0.99), and in patients who had T1a, T1b, and T2 disease, were 78.2%, 96.0%, and 82.1%, respectively (p = 0.43). All patients and tumor variables showed no statistically significant association with OS. Only low-grade acute toxicity was observed.

Conclusion: Non-inferiority results supported the HF schedule to ESGC, including high local disease control and decreased overall treatment time. Our study supports its efficacy in the primary care of ESGC with manageable side effects.