Zahra Siavashpour1, Mahdi Aghili2, Shabnam Anjidani3, Farid Zayeri4, Mona Molekzadeh Moghani5, Maedeh Maleki6, Ramin Jaberi7. 1. Radiotherapy Oncology Department, Shohada-e Tajrish Educational Hospital, Shahid Beheshti University of Medical Sciences, Tehran, Iran; Clinical Research Development Unit of Shohadaye Tajrish Hospital, Tehran, Iran. 2. Radiation Oncology Research Center, Iran Cancer Institute, Tehran University of Medical Sciences, Tehran, Iran. 3. Radiotherapy Oncology Department, Shohada-e Tajrish Educational Hospital, Shahid Beheshti University of Medical Sciences, Tehran, Iran. 4. Proteomics Research Center and Biostatics Department, School of Allied Medical Sciences, Shahid Beheshti University of Medical Science, Tehran, Iran. 5. Radiotherapy Oncology Department, Shohada-e Tajrish Educational Hospital, Shahid Beheshti University of Medical Sciences, Tehran, Iran; Clinical Research Development Unit of Shohadaye Tajrish Hospital, Tehran, Iran. Electronic address: m.malekzadeh@sbmu.ac.ir. 6. Brachytherapy Department, Rasoul Akram Educational Hospital, Iran University of Medical Sciences, Tehran, Iran. 7. Radiation Oncology Research Center, Iran Cancer Institute, Tehran University of Medical Sciences, Tehran, Iran; Department of Physics, University of Surrey, Guildford, UK.
Abstract
PURPOSE: This study investigated the correlation between the prescription dose and dose to the Manchester and International Commission on Radiation Units and Measurements-report 38 (ICRU-38) lymphatic trapezoid points during high-dose-rate (HDR) brachytherapy of locally advanced cervical cancer with (Cobalt-60) 60Co . METHODS AND MATERIALS: A retrospective study was designed for; patients with locally advanced cervical cancer, treated by external beam radiotherapy and concurrent weekly Cisplatin-based chemotherapy, had no extended parametrial invasion and was treated by tandem-ovoid set, from 2017 to 2020. Groupe Européen de Curiethérapie-European Society for Radiotherapy and Oncology (GEC-ESTRO) based target's volume, ICRU-89 revised version of Manchester points A and B, and ICRU-38 lymph node surrogate points were determined, and their dose was recorded. Paired sample t-test, linear regression analysis, and Pearson correlation analyses were done considering a statistical significance level of 0.05 and using IBM SPSS statistics (Version 23, IBM Crop.). RESULTS: Seventy-four brachytherapy cases were included. A positive and strong correlation was observed between D90 of clinical target volume (CTVHR) and points A and B dose for CTVHR〈 15 cc and 〉 35 cc. Strong and significant (p < 0.05) correlations were achieved between pelvic wall points dose and D90 and D100 of the obturator and between D50 and hot points of internal iliac lymph nodes. A strong correlation was obtained between D50 and D90 of external iliac lymph nodes and their ICRU points. CONCLUSIONS: Strong correlations were obtained between dose to the pelvic lymphatic chains and their historical ICRU-38 surrogate points during HDR brachytherapy of locally advanced cervical cancer patients with 60Co tandem-ovoid applicator sets. The correlation strength between point A and prescription dose highly depends on the CTVHR volume.
PURPOSE: This study investigated the correlation between the prescription dose and dose to the Manchester and International Commission on Radiation Units and Measurements-report 38 (ICRU-38) lymphatic trapezoid points during high-dose-rate (HDR) brachytherapy of locally advanced cervical cancer with (Cobalt-60) 60Co . METHODS AND MATERIALS: A retrospective study was designed for; patients with locally advanced cervical cancer, treated by external beam radiotherapy and concurrent weekly Cisplatin-based chemotherapy, had no extended parametrial invasion and was treated by tandem-ovoid set, from 2017 to 2020. Groupe Européen de Curiethérapie-European Society for Radiotherapy and Oncology (GEC-ESTRO) based target's volume, ICRU-89 revised version of Manchester points A and B, and ICRU-38 lymph node surrogate points were determined, and their dose was recorded. Paired sample t-test, linear regression analysis, and Pearson correlation analyses were done considering a statistical significance level of 0.05 and using IBM SPSS statistics (Version 23, IBM Crop.). RESULTS: Seventy-four brachytherapy cases were included. A positive and strong correlation was observed between D90 of clinical target volume (CTVHR) and points A and B dose for CTVHR〈 15 cc and 〉 35 cc. Strong and significant (p < 0.05) correlations were achieved between pelvic wall points dose and D90 and D100 of the obturator and between D50 and hot points of internal iliac lymph nodes. A strong correlation was obtained between D50 and D90 of external iliac lymph nodes and their ICRU points. CONCLUSIONS: Strong correlations were obtained between dose to the pelvic lymphatic chains and their historical ICRU-38 surrogate points during HDR brachytherapy of locally advanced cervical cancer patients with 60Co tandem-ovoid applicator sets. The correlation strength between point A and prescription dose highly depends on the CTVHR volume.