18. Primary vaginal cancer and vaginal recurrences - The GEC-ESTRO Handbook of Brachytherapy

Primary vaginal cancer and vaginal recurrences

7

THE GEC ESTRO HANDBOOK OF BRACHYTHERAPY | Part II Clinical Practice Version 1 - 01/09/2023

Figure 5a.

Figure 5b.

Figure 5. Example of the GEC-ESTRO target concept applied in a locally advanced primary vaginal cancer case. Re-used with permission from Schmid et al [12]. (a) T2-weighted MRI and clinical drawings at the time of diagnosis (upper row) and at the time of brachytherapy (lower row) in a woman with primary vaginal cancer in the upper third posteriorly, FIGO stage II. The patient was primarily treated with 46 Gy in 2 Gy fractions IMRT without concomitant chemotherapy, but with concomitant regional hyperthermia. The tumour showed good response, but significant residual disease was detected at the time of brachytherapy. A combined intracavitary and interstitial approach was used. The white arrow indicates the tumour on the MR images. The tumour is outlined in red on the clinical drawings. (b) Target delineation and OAR based on the recommended structures: GTV-Tres (white), CTV-T HR (red), CTV-T IR (blue), vagina outside CTV-T HR (light blue), bladder (yellow), rectum (light brown), sigmoid (green), bowel (olive), anal canal (dark brown), urethra (grey, partly depicted).

7. TUMOUR AND TARGET VOLUME

and brachytherapy. Concurrent chemotherapy may be considered depending on the origin and pathology of the primary tumour. Tumour infiltration and fistulation of urethra, bladder or rectum (T4) at initial presentation is not a contraindication for definitive radiotherapy including brachytherapy, however bladder, bowel or rectal diversion may be considered before the start of treatment, particularly for symptomatic patients. Alternatively, pelvic exenteration can be an alternative approach for definitive radiotherapy in selected cases. Selected patients with a previous history of vaginal or pelvic radiotherapy and non-metastatic disease may be offered re irradiation including EBRT and brachytherapy depending on their general condition, tumour extent and location, prognostic factors, previous radiotherapy dose, technique and dose distribution, and time-to-recurrence and re-irradiation.

Recommendations for target volume definition for EBRT and image-guided adaptive brachytherapy (IGABT) have been recently published by the Gynaecological GEC-ESTRO Working Group for primary vaginal cancer [12] and a collaboration between GEC ESTRO, American Brachytherapy Society (ABS) and Canadian Brachytherapy Group (CBG) for vaginal recurrences [17]. Target volume definition is based on imaging (primarily T2-weighted MRI) and gynaecological examination and is similar for both entities with only minor differences (see definitions below). The principle of response-adaptive target definition based on previous experiences with IGABT in primary cervical cancer described in the ICRU-89 report [18] was adopted as both primary and recurrent vaginal malignancies typically show substantial early response to chemoradiation. Therefore, availability of imaging and proper documentation of gynaecological examination at the