Beam Radiotherapy For Breast Cancer Research Articles

A Prospective Study on the Use of Deep Inspiration Breath-Hold Technique in External Beam Radiotherapy for Breast Cancer

Background Breast cancer is the most common cancer and the leading cause of death in women. The deep inspiration breath-hold (DIBH) technique helps reduce the dose received by the heart and lungs in breast cancers during adjuvant radiotherapy (RT). We present the dosimetry of heart and lungs with DIBH technique, reproducibility, and ease of execution. Materials and Methods This is a prospective study among breast cancer patients planned for adjuvant RT following either breast conservation or mastectomy. Patients received adjuvant RT to a dose of 42.5 Gy/16 Fr to the chest wall/whole breast followed by a boost of 10 Gy/5 Fr for breast conservation surgery patients with either three-dimensional conformal RT or volumetric modulated arc therapy technique. The dosimetric parameters such as lung mean dose, heart mean dose, and V25 Gy were compared between DIBH and free-breathing (FB) scans. Data were analyzed using SPSS software, and p-value <0.05 was considered statistically significant. Results The study was conducted from September 2018 to August 2020, and 32 patients were included. The compliance to the DIBH technique was good. The dose received by ipsilateral lung V20 (17 vs. 25%) and mean dose (9 vs. 12 Gy) were significantly lower in DIBH compared with FB (p < 0.001). The V5 (31 vs. 15%), V25 (9 vs. 2%), and mean dose (7 vs. 3.3 Gy) to the heart were much higher in FB compared with DIBH (p < 0.001). Conclusion DIBH-based RT treatment delivery for breast cancer patients requiring adjuvant RT showed good compliance and offers a significant reduction in radiation dose to the heart and lung.

Challenges in Treatment and the Importance of Radiotherapy in a Synchronous Endometrial and Breast Cancer

Abstract We report the case of a 69-year-old-female with synchronous endometrial and breast cancer. The imaging and pathology results confirmed the diagnosis. The patient underwent surgery and chemotherapy for endometrial cancer, and surgery followed by external beam radiotherapy for breast cancer. The patient’s clinical condition and imaging showed a favorable evolution after 2 months of follow-up.

A Prospective Study to Investigate the Placement of Setup Skin Markings for Larger Breasted Women Undergoing External Beam Radiotherapy (RT) for Breast Cancer

Background: The technique of placing all three skin marks (reference skin marks) on a single position during CT simulation for setup of patients undergoing conventional breast radiotherapy becomes a challenge when presented with larger breasted women (bra cup size ≥ D). A new way of using skin marks in setting these patients up has been developed where three skin marks are made on the patient (one on the sternum and two lateral skin marks more inferiorly beneath the breasts) for setup as against the departmental standard of using only a single skin mark on the sternum, and employing an SSD (Source to Skin Distance) technique. This study therefore reviewed the placement of the skin markings for larger breasted women undergoing external beam radiotherapy for breast cancer by quantifying treatment field alignment errors and setup errors between the two different setup techniques. Method: 36 patients were used in this study. Out of this number, 18 were setup using three reference skin marks and the remaining 18 were setup using one reference anterior skin mark. With an acceptable patient treatment field alignment error of 2 degrees, portal images (AP and lateral) of the different skin mark techniques were analysed for field alignment errors using an Iview GT system. More so, portal images (AP and lateral) of setup for both techniques were analysed for systematic (Σ) and random (σ) errors. Results:The AP images of the single skin mark setup and the three skin mark setup yielded no significant difference as they recorded a p- value (p<0.05) of 0.089 and 0.110 respectively when compared to the treatment field alignment threshold error of 2 degrees. The lateral images of the three skin mark also yielded no significant difference as a p- value (p<0.05) of 0.091 was recorded. The lateral images of the single skin mark yielded a significant difference with a p- value (p<0.05) of 0.026. Secondly, mean comparisons of the field alignment errors between the two setup techniques yielded no significant difference in the AP images as a p- value (p<0.05) of 0.089 was detected. On the contrary, a p- value (p<0.05) of 0.026 was recorded in the field alignment errors of the lateral images. This difference is significant. Lastly, random errors were reduced in all directions (AP- anterior-posterior, SI- superior-inferior and LR- Left-right) in the three skin mark setup (4.5mm AP, 4.9mm SI and 2.4mm LR) as compared to the single skin mark setup (4.7mm AP, 5.2mm SI and 2.6mm LR). Systematic errors were also reduced in the three skin mark setup (1.7mm AP and 1.8mm SI) compared to the single skin mark setup (2.0mm AP, 2.1mm SI). Systematic errors in the LR direction on the other hand increased from 2.0mm in the single skin mark to 2.2mm in the three skin marks. Conclusion For setup of larger breasted women undergoing external beam radiotherapy for breast cancer, the three skin mark setup technique is superior to the single skin mark setup technique.

Impact of rheumatoid arthritis on radiation-related toxicity and cosmesis in breast cancer patients: a contemporary matched-pair analysis.

To evaluate the impact of rheumatoid arthritis (RA) on toxicity and cosmesis in women undergoing radiotherapy for breast cancer. We queried an institutional database for women with RA treated with external beam radiotherapy for breast cancer between 1981 and 2016. Matching each patient to three controls without RA was attempted. Radiation toxicity was graded using CTCAE 4.0. Cosmesis was graded using the Global Harris Scoring System of Excellent, Good, Fair, or Poor. Grade 2+ (G2+) acute and late toxicities were compared between women with RA and their matched pairs using a generalized estimating equation (GEE). Wilcoxon test and mixed effects model were used to compare the cosmesis between two groups. Forty women with RA at time of radiation were matched to 117 controls. The median radiation dose was 60 Gy (50-66 Gy) and the median follow-up was 94months (1-354 months). When comparing the women with RA to their matched pairs, there was no significant difference in the rates of G2+ acute toxicity (25.0 vs. 13.7%, O 2.1, CI 0.91-4.9) or G2+ late toxicity (7.5 vs. 4.3%, OR 1.8, CI 0.48-6.8). Mean cosmesis was between Good and Excellent for both groups of patients, although women with RA were less likely to get Excellent cosmesis compared to their matched pairs (OR 0.35, CI 0.15-0.84). Among women with RA, radiation for breast cancer was well tolerated without significantly increased toxicity. Their cosmesis was generally Good to Excellent, although they might be less likely to get Excellent cosmesis compared to their matched pairs.

Second malignancies following conventional or combined ²⁵²Cf neutron brachytherapy with external beam radiotherapy for breast cancer.

We retrospectively evaluated the risk of second malignancies among 832 patients with inner or central breast cancer treated with conventional external beam schedule (CRT group), or neutron brachytherapy using Californium-252 (252Cf) sources and hypofractionated external beam radiotherapy (HRTC group), between 1987 and 1996 at the Institute of Oncology, Vilnius University. Patients were observed until the occurrences of death or development of a second malignancy, or until 31 December 2009, whichever was earlier. Median follow-up time was 10.4 years (range, 1.2–24.1 years). Risk of second primary cancers was quantified using standardized incidence ratios (SIRs). Cox proportional hazards regression models were used to estimate hazard ratios (HRs). There was a significant increase in the risk of second primary cancers compared with the general population (SIR 1.3, 95% CI 1.1–1.5). The observed number of second primary cancers was also higher than expected for breast (SIR 1.8, 95% CI 1.3–2.4) and lung cancer (SIR 3.8, 95% CI 2.0–6.7). For second breast cancer, no raised relative risk was observed during the period ≥10 or more years after radiotherapy. Compared with the CRT group, HRTC patients had a not statistically significant higher risk of breast cancer. Increased relative risks were observed specifically for age at initial diagnosis of <50 years (HR 2.9, 95% CI 1.6–5.2) and for obesity (HR 2.8, 95% CI 1.1–7.2).

An experimental attenuation plate to improve the dose distribution in intraoperative electron beam radiotherapy for breast cancer

Intraoperative electron beam radiotherapy (IOERT) is a technique in which a single-fraction high dose is intraoperatively delivered to subclinical tumour cells using an electron beam after breast-conserving surgery. In IOERT, an attenuation plate consisting of a pair of metal disks is commonly used to protect the normal tissues posterior to the breast. However, the dose in front of the plate is affected by backscatter, resulting in an unpredictable delivered dose to the tumour cells. In this study, an experimental attenuation plate, termed a shielding plate, was designed using Monte Carlo simulation, which significantly diminished the electron beam without introducing any backscatter radiation. The plate's performance was verified by measurements. It was made of two layers, a first layer (source side) of polymethyl methacrylate (PMMA) and a second layer of copper, which was selected from among other metals (aluminium, copper and lead) after testing for shielding capability and the range and magnitude of backscatter. The optimal thicknesses of the PMMA (0.71 cm) and copper (0.3 cm) layers were determined by changing their thicknesses during simulations. On the basis of these results, a shielding plate was prototyped and depth doses with and without the plate were measured by radiophotoluminescence glass dosimeters using a conventional stationary linear accelerator and a mobile linear accelerator dedicated for IOERT. The trial shielding plate functioned as intended, indicating its applicability in clinical practice.

Skin and chest wall dose with multi-catheter and MammoSite® breast brachytherapy: Implications for late toxicity

Purpose: Previous studies of external beam radiotherapy for breast cancer have shown that the risk of chest wall toxicity increases with larger fraction sizes. A recent experience using the MammoSite® (MS) reported a 12.5% incidence of chronic chest wall pain. Reports from several institutions using the multi-catheter (MC) technique have not shown elevated chest wall toxicity. Additionally, recent investigations have suggested that increased toxicity may occur with the MS when the dose to the skin, and perhaps chest wall, exceeds 125% of the prescribed dose. This investigation compares the skin and chest wall doses of a cohort of patients treated with the MC technique to a group treated with the MS.

Estimating Irradiated Heart Volume from 2D-Simulation Films in Tangential Beam Radiotherapy for Breast Cancer

Estimating Irradiated Heart Volume from 2D-Simulation Films in Tangential Beam Radiotherapy for Breast Cancer

Skin protection by use of sucralfate cream during external beam radiotherapy for breast cancer: a prospective double blind randomized phase II study

Skin protection by use of sucralfate cream during external beam radiotherapy for breast cancer: a prospective double blind randomized phase II study