Ovarian Malignancies Frequency in the Female Population from the Bryansk Region Living in Conditions of Radioactive, Chemical and Combine Contamination (2000–2020)

Background: Radioactive contamination and chemical pollution of the environment can affect the processes of carcinogenesis, including the formation of malignant neoplasms of the ovaries in women. We used the data of official state statistics for 2000–2020 to test the hypothesis about the effect of radioactive contamination (following the Chernobyl disaster) and chemical pollutants on the incidence of ovarian malignancies in the female population of the Bryansk region. Methods: A variety of statistical approaches were used to estimate the incidence of ovarian malignancies, including the Shapiro–Wilk test, Mann–Whitney U test, Spearman’s rank correlation test and linear regression. Results: We did not establish statistically significant differences in the frequency of primary morbidity of women with malignant neoplasms of the ovaries, regardless of the environmental conditions of living. Furthermore, no significant correlations were found between the frequency of primary morbidity of ovarian malignancies, both with the level of contamination by Cesium-137 and Strontium-90, and air pollution with volatile organic compounds, carbon monoxide, sulfur dioxide and nitrogen oxides. A statistically significant increase in the long-term trend in the frequency of ovarian malignant neoplasms was revealed in the areas of chemical pollution (p = 0.02), however, in other territories, no statistically significant regularities were established. The forecast of the frequency of newly diagnosed malignant neoplasms of the ovaries on average in the Bryansk region shows an increase of 12.4% in 2020 in comparison with the real data for 2020, while the largest increase in predicted values is recorded in the territories of radioactive contamination (by 79.6%), and the least in the combined territories (by 6.9%). Conclusions: The results obtained indicate the need for further work to understand the trends in the presence/absence of independent and combined effects of pollutants and the growth of oncogynecological pathology from the perspective of assessing the distant and regional metastasis, histological and immunohistochemical profile of a specific malignant ovarian neoplasm with levels of environmental contamination.

Brachytherapy for retinoblastoma: a 13 year experience

Brachytherapy (BT) is a method of radiation therapy with radioactive source contacting the tumor. It was proposed by P. Moore and H. Stallard in 1929. Despite those 50 years of experience with the use of BT in ophthalmic oncology, there are only a few studies on the use of Ru-106 BT for retinoblastoma (RB), and no publications on the use of Sr-90 BT have been found.Purpose. To present our own experience with the use of ruthenium and strontium ophthalmic applicators for BT in retinoblastoma.Materials and methods. 120 patients (137 eyes and 194 RB foci) received BT as a local treatment in the period from 2007 to 2020. At the time of treatment the age of the patients varied from 4 to 109 months (mean age 26 months). In 32% of cases (44 eyes) there were monofocal lesions, and in 68% of cases (93 eyes) — multifocal. In 36 cases (30%) BT was performed in the single eye. 79 patients (87 eyes) were treated with the use of ruthenium ophthalmic applicators (OAs), 25 patients (26 eyes) — with the use of strontium OAs, and for the treatment of 16 patients (24 eyes) both ruthenium and strontium OAs were used.Results. Clinically complete tumor regression was achieved in 62 % of cases (120 foci), partial tumor regression — in 31% of cases (60 foci). In 6% of cases (12 foci) continuous tumor growth was observed, and tumor recurrence occurred in 1% of cases (2 foci) within 4 to 6 months after BT. Local tumor control was achieved in 93% of cases.The single eyes were preserved in 92% of cases. BT complications of different intensity were reported in 38% of cases (46 patients — 49 eyes) with the mean follow-up duration of 55 months (3 to 157 months). In 92 % of cases (42 patients — 45 eyes) complications were associated with the use of ruthenium OAs, and only in 8% of cases (4 patients — 4 eyes) — with the use of strontium OAs. Risk factors for radiation-induced complications were identified: focus size (height more than 2.5 mm [P =0.0005], extension more than 7.3 mm [P <0,0001]), sclera dose more than 626 Gr (P = 0,0002), and the central localization of the tumor (P <0.0001).Conclusions. Ruthenium-106 and strontium-90 brachytherapy is a highly effective treatment modality for the management of RB.

Strontium 90 plesiotherapy for the treatment of eyelid squamous cell carcinoma in eight cats

Objectives Squamous cell carcinoma (SCC) is the most common eyelid tumour in cats. The main treatment is extensive surgery and the cosmetic outcome can be worrisome for some owners. Strontium 90 (ST-90) plesiotherapy is a therapeutic modality used for superficial tumours, including SCC. The aim of this study was to describe the use and response of feline eyelid SCC to ST-90 plesiotherapy either as single treatment or as adjuvant therapy following surgery. Methods A referral centre clinical database was searched for all cats diagnosed with SCC located on an eyelid. Cats treated with ST-90 plesiotherapy were included. The response to treatment was evaluated visually every 4–6 weeks until complete healing and based on response evaluation criteria in solid tumours (RECIST). Descriptive statistics of the survival were applied to the data collected. Results Eight cats treated between 2014 and 2017 met the inclusion criteria. The median age was 10.8 years. In six cases, ST-90 was used as the only treatment modality, while in two cats it was used as an adjuvant to surgery. Four cats received a single protocol and four a hypofractionated protocol. In the six cats in which ST-90 was used as the primary treatment, the response was 100%. Four cats died at a median time of 9 months (3–17 months) after ST-90 due to causes unrelated to SCC. Of the remaining four cats, three had no signs of recurrence at a median time of 34 months and one was lost to follow-up at 17 months with no signs of recurrence. Conclusions and relevance This small study showed that ST-90 can be used for treatment of eyelid SCC with good therapeutic and cosmetic outcomes.

Methodology for determining radiation dose distribution of strontium-90 applicators for veterinary intraoperatory betatherapy

Betatherapy is a modality within brachytherapy that uses beta radiation applicators, which are used in the treatment of superficial injuries. With the advancement of therapeutic techniques, new clinical protocols in veterinary medicine will be established. In this sense, betatherapy appears as an important option for performing radiotherapy procedures and, consequently, further studies are necessary to define the clinical oncological protocols. Therefore, the aim of this study was to present a methodology for determining the dose distribution of beta radiation from strontium-90 (90Sr) applicators for use in intraoperative radiotherapy in veterinary medicine. Planar radiation dose distributions from three 90Sr applicators were analyzed using radiographic films, which were exposed to beams from sources at different exposure times. The optical density (O.D.) of the radiation field was verified with a digital densitometer. After scanning the films, using the ImageJ software, the brightness intensities (BI) for the radiation exposure fields were measured. The analysis of the radiation dose distribution of the betatherapy applicators, produced results similar to those already described in the literature. The use of the ImageJ software, as well as the O.D. obtained, helped in the analysis of dosimetric studies. The behavior of the dose-effect curves provided a better understanding of the homogeneity of the radiation field in the treatment plan and, therefore, the radiation dose distributions in the treatment fields indicate the use of these types of applicators in veterinary radiotherapy procedures.

Strontium-90 brachytherapy following intralesional triamcinolone and 5-fluorouracil injections for keloid treatment: A randomized controlled trial

Background Keloid disease is hard to fully eradicate. Recurrence and other unsatisfactory results were found in many patients. No current therapeutic modality has been determined to be most effective for treating keloid scars. Intralesional corticosteroid injections is most commonly recommended for primary management of small and young keloids as well as hypertrophic scars. However, it’s difficult for patients to adhere to long-term triamcinolone acetonide injection therapy because of the pain, inconvenience or complications including hormonal imbalance or irregular menstruation. Objective We aimed to determine whether and how Strontium-90 brachytherapy as an adjuvant radiation could affect keloid recurrence after intralesional triamcinolone and 5-fluorouracil injections. Methods We included keloid patients from March 2019 to September 2019 and randomly allocated them to two groups after 3 intralesional triamcinolone and 5-fluorouracil injections at 3 weeks interval. The experimental group received Strontium-90 brachytherapy at a total dose of 15-20Gy, while the control group didn’t receive any adjuvant treatment. We performed both Vancouver Scar Scale scoring and Color Doppler ultrasound examination to monitor and evaluate lesions regularly. A one-year follow-up was completed for each patient. Results 31 patients who had 42 keloids in total were recruited. We found intralesional triamcinolone and 5-fluorouracil injections could effectively reduce the thickness and modify the hardness of small and young keloids. Strontium-90 brachytherapy reduced the one-year recurrence rate from 85.7 percent to 44.4 percent after 3 intralesional triamcinolone and 5-fluorouracil injections. The lesions’ thickness or elasticity was not affected by Strontium-90 brachytherapy. Conclusion Strontium-90 brachytherapy as an adjuvant radiation could effectively reduce small sized keloids recurrence after intralesional triamcinolone and 5-fluorouracil injections. It worked by enhancing the lesions’ stability post-injection. Trial registration The clinical trial registration number: ChiCTR2000030141. Name of trial registry: Chinese Clinical Trial Registry (http://www.chictr.org.cn/)