This document provides guidelines for delineating the clinical target volume (CTV) for the parametrium in radiation therapy treatment planning for cervical cancer. It defines the parametrium as the fat and connective tissue surrounding the uterus. The boundaries of the parametrial CTV are described, including superiorly at the top of the fallopian tubes, inferiorly at the pelvic floor muscles, anteriorly at the posterior bladder wall, and posteriorly at the mesorectal fascia and uterosacral ligaments. Special consideration is given to delineation when the uterosacral ligaments are involved with disease based on clinical or radiological findings.

1. MANAGEMENT OF DIFFUSE GLIOMAS
5/12/2023 1
DR KANHU CHARAN PATRO
MD,DNB (Radiation Oncology),MBA,FICRO,FAROI(USA),PDCR,CEPC
HOD(Radiation Oncology)
Mahatma Gandhi Cancer Hospital And Research Institute, Visakhapatnam
drkcpatro@gmail.com M-9160470564
TARGET DELINEATION OF PARAMETRIUM

2. What is PARAMETRIUM?
1. The fat and connective tissue that
surrounds the uterus.
2. The parametrium helps connect the uterus
to other tissues in the pelvis.

3. PARAMETRIUM content?
1. The parametrium includes the superficial uterine pedicle (uterine artery and superficial
uterine vein) and related connective tissue and lymphatic channels.
2. The connective tissue crossing below the ureter is considered paracervix.

4. GUIDELINE

5. CTV CERVIX

6. PARAMETRIUM

7. BOUNDARY

8. BOUNDARY
1. Superior boundaries of the parametria are at the top of the fallopian tube, and
contours should stop once loops of bowel are seen next to the uterus as this is
clearly above the broad ligament.
2. For the very anteverted uterus, particularly where the fundus lies below the
cervix, the parametrial volume should stop once the cervix is seen.
3. Inferiorly, the parametrial tissue finish at the muscles of the pelvic floor.
4. Anteriorly, the parametrial boundary lies at the posterior wall of the bladder.
5. In patients with a very small bladder (which lies deep in the pelvis), it was
decided to set the anterior parametrial boundary in line with the posterior
border of the external iliac vessels.
6. Posteriorly, the parametrial tissue is bounded by the mesorectal fascia and
uterosacral ligaments.
7. Laterally, the parametrial volume should extend to the pelvic sidewall (excluding
bone and muscle).

9. THE PARAMETRIUM IN MRI

10. UTEROSACRAL LIGAMNET

11. UTEROSACRAL LIGAMNET
MRI, axial view, showing the dorsal to ventral
direction of the uterosacral ligament (USL)
( red arrow ) with its insertion to the cervix
( Cx ), Bladder ( B ), and rectum ( Rec

12. Uterosacral coronal view

13. UTEROSACRAL LIGAMNET INVOLVEMENT

14. ADRESSSING UTEROSACRAL LIGAMENT
1. Care must be taken to include the entire
uterosacral ligaments if they are either
clinically or radiologically involved with
disease.
2. If this is the case, an argument can be
made to include the entire mesorectum
as pararectal lymph nodes would also be
at risk.
3. In that case, parametrial volumes would
extend up to the rectal contour (Fig. 5).
4. Patients with (FIGO) stage 3B or greater
disease and those with extensive nodal
involvement should also have the entire
mesorectum included in the parametrial
volume

15. OVERLAPING WITH NODAL VOLUME
1. It is acknowledged that there
would be some overlap of this
volume with the nodal CTV,
particularly along the obturator
strip.
2. The pelvic sidewall was
considered a more consistent
and reproducible boundary and
any overlap between the two
volumes could be dealt with
during treatment planning.

16. THANK YOU