ESTRO 2024 - Abstract Book

S255

Brachytherapy - Gynaecology

ESTRO 2024

The recommended dose points corresponding to upper vagina were plotted at the 3, 6, 9 and 12 o clock position at the surface of the inner vaginal wall and at a depth of 5mm. The dose at the ICRU recto-vaginal (RV) point was also documented. The recommended vaginal reference length (VRL) was also documented. The centre of the ring sources in Westewald et al corresponds to the centre of flange at cervical os in a tandem- ovoid application. Hence, VRL was recorded extending from the cervical os (flange) to the PIBS point.

Statistical analysis was performed using the Pearson’s Correlation test.

Results:

43 consecutive applications belonging to 29 patients were selected. Mean length of upper, mid, lower vagina were 3.89 + 1.07cm, 2.45 + 0.34cm, 1.87 + 0.40cm respectively. There was a significant difference in the sum total vaginal length (8.26+/-1.07cm) vs the recommended vaginal reference length (5.39 + 0.87) (p=0.0001). The mean doses to D5cc, D2cc, D1cc and D0.1cc and dose point details of the upper, mid and lower vagina are elaborated below.(Table) Moderate positive correlation could be established only between the RV point, 6 o'clock upper vaginal dose point(C) vs the D5cc, D2cc, D1cc and D0.1cc of the upper vagina. Negligible correlation was noted between the PIBS +2, PIBS-2 point doses vs DVH parameters of mid/lower vagina.