Effect of treatment interruptions and outcomes in cancer patients undergoing radiotherapy during the first wave of COVID-19 pandemic in a tertiary care institute.

INTRODUCTION: COVID-19 patients with cancer had poorer outcomes due to immunosuppression during cancer care, poor general condition, and other comorbidities. The study was conducted to present the real-world analysis of the effect of treatment interruptions on the outcomes of patients treated with radiation therapy during the first wave of the COVID-19 pandemic in a tertiary care institute in India. MATERIALS AND METHODS: The study is a retrospective observational cohort study on cancer patients undergoing radiation therapy from March 2020 to January 2021. The study's primary outcome was to analyze the effect of treatment interruptions on the outcomes of patients treated with radiation therapy during the first wave of COVID-19 pandemic. RESULTS: Between March 2020 to January 2021, 218 eligible patients undergoing radiation therapy were found for the study. Among the 218 patients, 25 patients (11.47%) were found positive for COVID-19, while 193 patients (88.53%) were negative for COVID-19. Among COVID-19-positive patients, ten patients had < 3 weeks of treatment interruption, while 15 patients had > 3 weeks of treatment interruptions. After recovering from COVID-19, treatment was resumed and completed for 15 (60.00%) of the COVID-19-positive patients. In comparison, 13 patients (52.00%) were lost to follow-up. Three of the COVID-19-positive patients died. The disease was clinically controlled in 12 (48.00%) of the COVID-19-positive patients, and the patients reported locoregional disease progression in 10 (40.00%). Among the 193 COVID-19-negative patients, 32 patients (16.58%) had treatment interruption. Twelve patients (37.50%) had treatment interruptions for less than 1 week. There was a significant difference in the delay of radiation treatment delivery by 2 weeks (11 fractions) in COVID-19-positive patients compared to only two fractions delay in COVID-19-negative patients. CONCLUSION: COVID-19 impacted the treatment outcomes in both COVID-19-positive and COVID-19-negative cohorts of patients. There was a longer duration of treatment interruptions in the COVID-19-positive patients, leading to fewer patients completing the radiation treatment and thereby increased locoregional disease progression. There was a significant difference in the delay in treatment between the two groups.

A Dosimetric Study Comparing 3D-CRT vs. IMRT vs. VMAT in Left-Sided Breast Cancer Patients After Mastectomy at a Tertiary Care Centre in Eastern India.

Introduction Post-mastectomy radiation in left-sided breast cancer in women continues to pose a significant risk to the underlying lungs and heart. This study analyzed the difference in planning target volume (PTV) coverage and dose to the organs at risk (OAR) by using three different planning methods for the same patient - three-dimensional conformal radiotherapy (3D-CRT), intensity-modulated radiotherapy (IMRT), and volumetric-modulated arc therapy (VMAT). Material and methods Thirty-five left-sided breast cancer patients' post-mastectomy were included in this study, and three different plans for adjuvant radiation were created using 3D-CRT, IMRT, and VMAT. The prescribed dose was 50Gy in 25 fractions. Kruskal-Wallis analysis of variance (ANOVA) was done, followed by a pairwise t-test to establish a hierarchy of plan quality and dosimetric benefits. The plans were compared with PTV95, homogeneity index (HI), conformity index (CI), hotspot (V107%), left lung V20Gy, mean lung dose, heart V25Gy, mean heart dose, and integral dose (ID) to the body. Results Both VMAT and IMRT led to improved PTV95% coverage (95.63±1.82%, p=0.000 in VMAT; 93.70±2.16 %, p=0.000; 81.40±6.27% in 3D-CRT arm) and improved CI (0.91±0.06 in IMRT [p<0.05] and 0.96±0.02 for VMAT plans [p<0.05]) as compared to 3D-CRT (0.66±0.11), which was statistically significant on pairwise analysis. In contrast, the difference in HI and reduction in hotspots were not significantly different. Left lung V20 was statistically very different between the three arms with the highest values in IMRT (36.64±4.45) followed by 3D-CRT (34.80±2.24) and the most negligible value in VMAT (33.03±4.20). Mean lung dose was also statistically different between the three arms. There was a statistically significant difference in mean heart dose between the three arms on pairwise analysis. Both the inverse planning methods led to a statistically significant increase in low dose volume (V5 and V10) of the ipsilateral lung, opposite lung, and heart, and increased ID to the body excluding the PTV. Conclusion While both the inverse planning modalities led to increased coverage, better CI, and better HI and decreased high dose volumes in OARs, there was increased low volume irradiation of heart, lungs, and body with VMAT faring marginally better than IMRT in coverage and decreasing lung irradiation with comparable heart irradiation.

High-Dose-Rate Intracavitary Brachytherapy Under Conscious Sedation a Viable Practical Alternative to Spinal Anaesthesia in Carcinoma Cervix: A Retrospective Study in a Tertiary Care Centre in Eastern India.

Introduction Intracavitary brachytherapy (ICBT) is an integral component in the management of locally advanced cervical cancer. Spinal anaesthesia is the preferred mode of pain management during brachytherapy procedures. In high volume, resource constraint settings, it is difficult to provide spinal anaesthesia to all patients. This study attempts dosimetric comparison of high-dose-rate ICBT with spinal anaesthesia to that under conscious sedation to find out whether brachytherapy under conscious sedation is comparable with spinal anaesthesia. Methods Retrospective data of total of 56 cervical cancer patients who received ICBT after completion of external beam radiotherapy (EBRT) were collected. Among these 56 patients, 28 patients received brachytherapy under spinal anaesthesia (SA group) and the rest under conscious sedation (CS group). Brachytherapy dose was 7 Gray per fraction weekly for three weeks. Thus, 84 brachytherapy plans of each group were analysed with respect to doses received by points A, B, P and Organs at Risk. Results The mean doses received by points A, B and P were comparable in SA and CS groups (p-value >0.05). Similarly, the mean doses received by Organs at Risk (rectum, urinary bladder, and sigmoid colon) were also comparable in both the groups (p-value>0.05). Conclusion ICBT under CS is dosimetrically non-inferior to SA, which makes it an alternative option.