Impact of breath hold on regional nodal irradiation and heart volume in field in left breast cancer adjuvant irradiation

PURPOSE

Compared to the free-breathing technique, adjuvant left breast irradiation after breast-conserving surgery or mastectomy using the breath-hold method significantly reduces the heart mean dose, Left anterior descending artery, and ipsilateral lung doses. Movement with deep inspiration may also reduce heart volume in the field and regional node doses.

MATERIALS AND METHODS

Pre-radiotherapy planning CT was performed in the free-breathing, and breath-hold techniques using RPM, demographic information, clinicopathological data, heart volume in the field, heart mean dose, LAD mean dose, and regional nodal doses were calculated in both free breathing and DIBH. Fifty patients with left breast cancer receiving left breast adjuvant radiation were enrolled.

RESULTS

There was no significant difference in axillary LN coverage between the two techniques, except for SCL maximum dose, Axilla I node maximum dose, and Axilla II minimum dose in favor of the breath hold technique. The mean age was 47.54 years, 78% had GII IDC, 66% had positive LVSI results, and 74% of patients had T2. The breath hold strategy resulted in considerably decreased mean heart dose (p = 0.000), LAD dose (p = 0.000), ipsilateral lung mean dose (p = 0.012), and heart volume if the field (p = 0.013). The mean cardiac dosage and the dose of the LAD were significantly correlated (p = 0.000, R = 0.673). Heart volume in the field and heart mean dosage was not significantly correlated (p = 0.285, r = - 0.108).

CONCLUSION

When compared to free breathing scans, DIBH procedures result in considerably reduced dosage to the OAR and no appreciable changes in dose exposure to regional lymph node stations in patients with left-sided breast cancer.

Analytical dosimetric study of intensity-modulated radiotherapy (IMRT) and volumetric-modulated arc therapy (VMAT) for prostate cancer

PURPOSE

The study aimed to compare the dosimetric results and treatment delivery efficiency among four techniques to explore the preferred technique in prostate treatment.

MATERIALS AND METHODS

7 IMRT, 9 IMRT, 1 ARC, and 2 ARC plans were created for 30 prostate cancer patients using the Eclipse™ treatment planning system (Varian Medical Systems). All the plans were designed to deliver 80.0 Gy in 40 fractions to the prostate planning target volume (PTV). Target coverage, organs at risk (OARs), number of monitor units, homogeneity, and conformity were compared across the four techniques to assess the quality of the plans.

RESULTS

The study revealed better Planning Target Volume (PTV) dose coverage in the VMAT-2A than in the other plans. At the same time, VMAT-2A plans were found to be significantly lower in terms of Bladder and rectum doses than other techniques. In addition, VMAT has the advantage of considerably reducing the number of monitor units and treatment time.

CONCLUSION

For prostate cancer, VMAT may offer a favorable dose gradient profile, conformity, and MU and treatment time compared to IMRT.

Impact of breath-hold technique on incidence of cardiac events in adjuvant left breast cancer irradiation

BACKGROUND

This study aims to compare the incidence of cardiac events and to identify its predictors in left breast cancer patients receiving adjuvant radiotherapy using breath-hold technique (DIBH) versus free breathing technique (FB).

METHODS

We conducted a retrospective multi-center study of two arms; the free breathing arm included 208 patients who were treated with traditional radiotherapy treatment technique, while DIBH arm included 224 patients who were treated with breath-hold technique using The Varian Real-time Position Management (RPM). We retrospectively reviewed the medical records of the patients from January 2010 to December 2017.

RESULTS

The mean dose to the heart and left anterior descending artery were significantly lower in the DIBH arm (2.10 ± 0.39 and 6.16 ± 0.18 Gy) compared with (4.29 ± 0.60 Gy and 12.69 ± 0.93 Gy, respectively) in the FB arm. The incidence of cardiac events was higher in the FB arm than in the DIBH arm, but it was not statically significant. Our analysis revealed that age, diabetes, hypertension, smoking, mean LAD dose, and heart mean dose were significant prognostic factors for the occurrence of cardiac events in the breath-hold arm. Hypertension, smoking, as well as heart mean dose were independent risk factors for the occurrence of cardiac events.

CONCLUSION

Use of the DIBH technique resulted in a significant reduction in doses to the heart, LAD and lesser cardiac events incidence compared to free breathing.

Evaluation of the Effect of Axillary Radiotherapy Dose and the Development of Lymphedema in Breast Cancer Patients

Purpose

The present study is aiming to correlate different radiotherapy techniques, fractionations, and doses received by each axillary LN level and axillary vessels with the development of breast cancer-related lymphedema (BCRL).

Methods and Materials

We retrospectively studied 181 female breast cancer patients who were diagnosed and treated by radiation therapy during the period from January 2012 to December 2017. The radiotherapy treatment plans were recalled from the archives. The axillary LN levels I, II, III, supraclavicular LN were contoured as well as axillary vessels. New dose volume histograms were generated to correlate between the radiotherapy dose t and the development of BCRL.

Results

The study included 162 patients treated with a 3D radiotherapy technique and 19 treated with a 2D radiotherapy technique; 124 patients underwent MRM, while 57 patients underwent BCS; 117 patients were treated with a hypofractionated technique, while 64 patients were treated with a conventional radiotherapy technique. The cumulative incidence of BCRL after radiotherapy was 20.4%. There was a statistically significant relationship between the 2D radiotherapy technique compared with 3DCRT and development of lymphedema (55 vs. 16.6, respectively; p < 0.001). Patients who were treated with conventional radiotherapy had significantly higher rates of lymphedema (42.2%) compared with hypofractionated radiotherapy (8.5%) (p < 0.001). There was a non-significant relationship between mean radiotherapy dose to axillary levels or axillary vessels and development of lymphedema.

Conclusion

Breast cancer radiotherapy with the 2D technique and conventional fractionation protocol might increase the risk of BCRL. No correlation was observed between radiotherapy dose to each axillary LN level, axillary vessels and BCRL.

Evaluation of Serum Levels of Insulin-Like Growth Factor 1 and Insulin-Like Growth Factor-Binding Protein 3 in Patients With Colorectal Cancer: A Case-Control Study

Background/aim: Limited information is available about the relationship between colorectal cancer (CRC) and serum concentration of insulin-like growth factor 1 (IGF1) and insulin-like growth factor-binding protein 3 (IGFBP3). This study aims to compare the serum levels of IGF1and IGFBP3 in colorectal cancer cases and controls and to assess the relationship between their level and the demographic and histopathological characteristics.

Methods: A case-control study in which 50 patients with colorectal cancer and 50 controls matched by gender and age were compared regarding the demographic characteristics and the level of both IGF1 and IGFBP3. The correlation with different clinicopathological features was assessed.

Results: Levels of IGF1 were significantly higher while levels of IGFBP3 were significantly lower among cases compared to control. IGF1 was significantly higher among patients with liver metastasis, lymph node (LN) spread, and lymphovenous invasions and did not show significant association with gender, smoking status, family history, or primary site of colorectal cancer. Lower IGFBP3 was significantly high among patients with liver and lymph node metastasis, lymphovenous invasion, and patients with positive family history. This significant negative correlation was also detected between IGFBP3 levels and the size of the tumor.

Conclusions: High IGF1 levels and low concentrations of IGFBP3 are related to colorectal cancer and were significantly associated with liver metastasis, lymph node spread, and lymphovenous invasions. Further research is recommended to investigate if circulating IGF1 and IGFBP3 levels can be used to identify people at high risk of colorectal cancer and to investigate potential lifestyle or pharmaceutical ways to lower IGF1 bioactivity as a risk reduction strategy.

The effect of metformin when combined with neoadjuvant chemotherapy in breast cancer patients

Metformin has been used to treat type 2 Diabetes Mellitus since long time. It has two proposed anti-neoplastic mechanisms, direct (insulin-independent) and indirect (insulin-dependent) actions. To assess the effect of Metformin on pathological response when combined with neoadjuvant chemotherapy in breast cancer. A prospective study included stage II, III non-diabetic breast cancer patients who received neoadjuvant chemotherapy in our center during the period from May 2017 to March 2019. 59 patients met our inclusion criteria and completed the study, 27 patients received 850 mg Metformin every 12 h with chemotherapy (group A), and 32 patients received chemotherapy without Metformin (group B). Pathological response was assessed by Chevallier classification and residual cancer burden score (RCB). Both groups were well balanced regarding baseline characteristics. The results of our study showed that the rate of pathological complete response (pCR) was 14.8% in group (A) vs. 6.3% in group (B) with a P value of 0.39. RCB class 3 was 40.7% in group (A) vs. 68.8% in group (B) which was statistically significant with a (P value of 0.031). Patients with triple-positive histology who had RCB class 3 were only (14.3%) in group (A) versus (60%) in group B. Patients with body mass index (BMI) ≥ 25 who had RCB 3 were 40% and 66.7% in group (A) and (B), respectively. Metformin may increase the pCR especially in patients with BMI ≥ 25 and patients with triple-positive histology, a larger phase III study is needed to confirm this finding.

The Impact of Chest Wall Boost on Reconstruction Complications and Local Control in Patients Treated for Breast Cancer

PURPOSE

Giving an additional radiation dose to the incision or chest wall has been a practice, but it has never been studied in a randomized setting, and it might lead to inferior cosmetic outcomes. This study aims to evaluate whether delivery of a chest wall boost (CWB) to the mastectomy scar or chest wall is independently associated with reconstruction complications and to assess its disease control efficacy in the setting of breast reconstruction.

METHODS AND MATERIALS

We conducted a retrospective chart review of 746 patients with breast cancer who underwent mastectomy, breast reconstruction, and PMRT; all underwent treatment at our institution during 1997 to 2016. Various reconstruction techniques were used among this cohort including autologous reconstruction, single-stage direct-to-implant reconstruction, and 2-stage tissue expander implant. Cohorts were divided by administration of CWB. The primary objective was comparing the rate of reconstruction complications including skin necrosis, fat necrosis and infection between groups. Subgroup analysis for patients with implant-based reconstruction was performed to evaluate the effect of CWB on implant-related complications such as capsular contracture, implant exposure, and implant failure. The secondary objective was comparison of the cumulative incidence of local failure between groups overall and within clinically high-risk subgroups.

RESULTS

The median follow-up was 5.2 years. Most clinicopathologic features were well balanced between the 379 (51%) patients who received CWB and the 367 (49%) who did not. On multivariate analysis, CWB was significantly associated with infection, skin necrosis, and implant exposure. For implant reconstruction patients, CWB independently increased risks of implant failure. CWB administration was not associated with local tumor control benefits, even in high-risk subgroups.

CONCLUSIONS

Our findings suggest that omission of chest wall boost in postmastectomy radiation improves breast reconstruction outcomes without compromising local tumor control.