ESTRO 2022 - Abstract Book

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Abstract book

ESTRO 2022

in this population. Non-squamous cell histology is also considered to be a risk factor for recurrence. This study aims to identify the impact of multiple high-risk factors on overall survival outcomes to identify a patient population that may potentially benefit from intensified therapy. Materials and Methods The National Cancer Data Base was queried for women with surgically resected, high-risk cervical carcinomas between 2004 and 2017 treated with adjuvant chemoradiation. Kaplan-Meier with log-rank test and Cox proportional hazards tests were utilized for overall survival (OS) calculations. The risk-factor sum was assigned one point per risk factor including: positive parametrial involvement, positive lymph nodes, positive surgical margins, and non-squamous cell histology. Results A total of 7,562 women met inclusion criteria. Of those, 1,681 (22.2%) had only adenocarcinoma as a risk factor, 1,970 (26.1%) had two risk factors, 3,228 (42.7%) had three risk factors and 683 (9.0%) had all four risk factors. Five-year overall survival for women with 1, 2, 3, and 4 risk factors was 82.0%, 75.4%, 72.1%, and 51.7%, respectively (p<0.001). Among women with 1-3 risk factors, non-squamous cell histology was predictive of worse 5-year OS in each echelon: 75.6% vs 67.9%; 78.1% vs 72.5%; 70.9% vs 48.7%, respectively (p<0.001). On Cox multivariable analysis, a higher number of risk factors were predictive for a statistically significant increased risk of death along with a number of other factors (Table 1).

Conclusion The number of high risk factors that serve as indicators for adjuvant chemoradiation along with non-squamous cell histology predicts for overall survival in women treated with adjuvant chemoradiation following radical hysterectomy for cervical cancers. These factors may be utilized to identify a patient population that may benefit from treatment intensification in the future.

PD-0910 Early outcomes of abbreviated brachytherapy schedule for cervix cancer during COVID pandemic.

S. Chopra 1 , J. Mulani 1 , M. Singh 2 , A. Shinde 3 , P. Mittal 3 , L. Gurram 3 , L. Scaria 4 , D. A 5 , S. Kohle 5 , P. Rane 5 , Y. Ghadi 5 , S. Rath 6 , J. Ghosh 7 , S. Gulia 6 , S. Gupta 7 , R. Kinhikar 5 , S. Laskar 3 , J.P. Agarwal 3 1 Advanced Centre for Treatment, Research and Education in Cancer, Tata Memorial Centre, Homi Bhabha National Institute, Radiation Oncology, Navi Mumbai, India; 2 Tata memorial Hospital, Tata Memorial Centre, Homi Bhabha National Institute, Radiation Oncology, Mumbai, India; 3 Tata Memorial Hospital, Tata Memorial Centre, Homi Bhabha National Institute, Radiation Oncology, Mumbai, India; 4 Tata Memorial Hospital, Tata Memorial Centre, Homi Bhabha National Institute, Medical Physics , Mumbai, India; 5 Tata Memorial Hospital, Tata Memorial Centre, Homi Bhabha National Institute, Medical Physics, Mumbai, India; 6 Tata Memorial Hospital, Tata Memorial Centre, Homi Bhabha National Institute, Medical Oncology, Mumbai, India; 7 Advanced Centre for Treatment, Research and Education in Cancer, Tata Memorial Centre, Homi Bhabha National Institute, Medical Oncology, Navi Mumbai, India Purpose or Objective COVID-19 pandemic led to restructuring of cancer care. In India, a nationwide complete lockdown was announced in March, 2020 which was released in a phased manner. Cervical cancer brachytherapy (BT) was listed as level 1 priority across consensus guidelines that also recommended reduced insertions. We present early outcomes of abbreviated schedule. Materials and Methods Patients treated with (chemo) radiotherapy and BT from April 2020 to March 2021 and who received single insertion and multiple fractions (3-5) BT over a 24-48 hrs either due to infrastructural resource constraints or excessive prolongation of overall treatment time (OTT) were included. Those with central/medial parametrial disease at BT received intracavitary(IC) and those with poor response or unfavourable organ at risk doses received Intracavitary-interstitial (IC+IS) application. IBS- GEC ESTRO-ABS guidelines were used for high risk clinical target volume (HRCTV) delineation. Treatment protocol included single implant and 3-5 BT fractions of BT 5-8.5 Gy with an aim to achieve point A dose of 70 Gy EQD2 10Gy or HRCTV dose> 85 Gy EQD2 10Gy while maintaining bladder (B2cc), rectum (R2cc), sigmoid (S 2cc) doses of 90 ,75 and 75 Gy EQD2 3Gy. Time to event analysis was used to report oncological endpoints. Toxicity was reported using crude proportions. Results Three hundred and sixteen patients received radical treatment. Sixty four patients (20%) received abbreviated BT schedule. While 29.7% (19) patients had FIGO stage IB2-IIB, 70.3 %(45) had stage III-IV. Due to the pandemic only 77% (n=49) patients